CN220358279U - Battery cells, batteries and electrical devices - Google Patents

Abstract

The application discloses battery monomer, battery and power consumption device, battery monomer includes: the shell assembly comprises a shell and a first polar column, wherein the first polar column comprises a polar column body and a first cover plate, the polar column body is arranged on the shell, and the first cover plate is arranged on the polar column body; the battery cell assembly comprises an active material coating part and a conductive part connected with the active material coating part, wherein the active material coating part is accommodated in the shell, and the conductive part is connected with the pole body through a first welding part; the first welding part is at least partially positioned on one side of the pole body, which is away from the active material coating part, and the first cover plate is used for shielding the first welding part. This application can make first welding portion keep away from active material coating portion, reduces the produced high temperature of welding and to the influence of active material coating portion, reduces the probability that active material coating portion received the damage, and first apron can play the guard action, weakens the produced high temperature when utmost point post body welds to the influence of first welding portion, improves battery monomer's reliability.

Description

Battery cells, batteries and electrical devices

Technical field

The present application relates to the field of battery technology, and in particular, to a battery cell, a battery and an electrical device.

Background technique

In recent years, new energy vehicles have developed by leaps and bounds. In the field of electric vehicles, batteries, as the power source of electric vehicles, play an important and irreplaceable role. Usually, a battery includes multiple battery cells. There is a certain risk of thermal runaway or short circuit in the battery cells during use, which leads to poor reliability of the battery cells and is not conducive to improving the performance and service life of the battery cells.

Utility model content

Embodiments of the present application provide a battery cell, a battery and a power device, which can reduce the probability of thermal runaway or short circuit of the battery cell, improve the reliability of the battery cell, and improve the performance and service life of the battery cell.

In a first aspect, embodiments of the present application provide a battery cell, including: a case assembly, including a case and a first pole. The first pole includes a pole body and a first cover. The pole body is installed in the case. body, the first cover plate is arranged on the pole body; the battery core assembly includes an active material coating part, and a conductive part connected to the active material coating part, the active material coating part is accommodated in the housing, and the conductive part passes through the first The welding part is connected to the pole body; the first welding part is at least partially located on a side of the pole body away from the active material coating part, and the first cover is used to shield the first welding part.

In the above technical solution, the first welding part is at least partially located on the side of the pole body away from the active material coating part. On the one hand, it can reduce the metal residue generated during the welding process from entering the battery cell, and prevent the metal residue from entering to a certain extent. Overlap the positive and negative electrode plates to reduce the possibility of internal short circuit in the battery cells. On the other hand, the first welding part can be kept away from the active material coating part. When the pole body and the conductive part are welded at high temperature to form the first welding part, since the first welding part serves as a high temperature heat source and can be far away from the active material coating part, it can Reduce the impact of high temperature generated by welding on the active material coating, reduce the probability of damage to the active material coating, and improve the reliability of the battery cells. In addition, after the pole body is welded to the conductive part inside the casing, when the battery cell is welded to the bus part, the first cover plate blocks the first welding part, which can play a protective role and weaken the power when the pole body is welded to the bus part. The generated high temperature affects the first welding part and improves the connection reliability between the pole body and the conductive part.

In some embodiments, the pole body has a first receiving groove, the surface of the first pole facing the active material coating part is the inner end surface of the pole, and the notch of the first receiving groove is formed on the inner end surface of the pole, and The first receiving groove has a first end wall and a first side wall. The first end wall is located on a side of the first side wall away from the active material coating part. At least part of the conductive part is accommodated in the first receiving groove. The welding part is provided on the first end wall, and the first cover plate cooperates with the pole body and covers the first welding part.

In the above technical solution, on the one hand, the first receiving groove is provided on the first pole, which can reduce the weight of the first pole to a certain extent, thereby improving the weight energy density of the battery cell and battery; on the other hand, due to the first The notch of the receiving groove is formed on the inner end surface of the pole, and the inner end surface of the pole is the surface of the first pole close to the active material coating part, so that the first receiving groove can face the direction of the active material coating part Open, thereby facilitating the conductive part to extend into the first receiving groove, thereby improving assembly efficiency. Moreover, this form of the first receiving groove facilitates processing and improves production efficiency.

Moreover, the first accommodation tank can be easily processed to have a larger volume and can accommodate more conductive parts; at the same time, since the first accommodation tank is open toward the direction of the active material coating part, the first accommodation tank can also be used as an electrolyte. The buffer and temporary storage structure allows the casing to accommodate more electrolyte. Since the battery cell will lose electrolyte during the charging and discharging process, when there is more electrolyte, the service life of the battery cell can be extended; and also because The first accommodating groove is open toward the direction of the active material coating part. The first accommodating groove can also be used as an accommodating and buffering structure for the gas produced inside the battery cell assembly, reducing the expansion of the battery cells and improving the reliability and stability of the battery cells. .

In addition, since the first receiving groove is located inside the first pole, external foreign matter and impurities cannot easily enter the first receiving groove, thereby reducing the impact of external foreign matter and impurities on the battery cell assembly and improving the stability and reliability of the operation of the battery cell assembly. properties, thereby improving the stability and reliability of battery cells and batteries. Secondly, by arranging the first welding part between the pole body and the conductive part on the first end wall, on the one hand, the first welding part can be further away from the active material coating part when it is in the first containing groove, and further Reduce the impact of the high temperature generated when the pole body and the conductive part are welded to form the first welding part on the active material coating part; on the other hand, not only the first accommodating groove not only has the function of accommodating at least part of the conductive part, but also the first accommodating groove The groove wall also has the function of electrically connecting with the conductive part, which can simplify the structure of the first pole and facilitate the processing of the first pole. It can also simplify the structure of the conductive part, reduce the redundancy of the conductive part, and reduce the conductivity. department costs. Moreover, by using the welding of the first end wall and the conductive part, the welding area formed by the first welding part can be set relatively large, which not only reduces the difficulty of welding, but also improves the reliability and stability of the welding, thereby improving the battery Monolithic performance.

In addition, since the first welding part is located in the first receiving groove, it can not only prevent the first welding part from protruding from the outside of the first pole and occupy the space outside the first pole, but also enable the first welding part to obtain the third The protection of a cover plate improves the welding reliability and stability of the conductive part and the first pole.

In some embodiments, the first end wall has a first sinking groove, and at least part of the first welding portion is located in the first sinking groove.

In the above technical solution, on the one hand, the first sinking groove can be used to pre-position and limit the first welding part, which not only helps to find the correct position for welding and improves production efficiency, but also helps to improve the stability and reliability of the conductive part. properties to ensure the stability and reliability of the charging and discharging process of the battery cell; on the other hand, by setting the first sinking groove on the first end wall, the local wall thickness of the first end wall can be locally thinned, which is not only beneficial to Welding can also help reduce the weight of the first pole and increase the weight energy density of the battery cell.

In some embodiments, the first pole has a first groove, a side surface of the first pole away from the active material coating part is the outer end surface of the pole, and the notch of the first groove is formed on the outer end surface of the pole. , the first cover plate covers the notch of the first groove.

In the above technical solution, on the one hand, since the first pole is provided with the first groove, the weight of the first pole can be further reduced, thereby improving the weight energy density of the battery cell and the battery; on the other hand, the first pole The groove is located outside the first pole, that is, it is open toward the side of the first pole away from the inside of the casing. The first groove can be used to accommodate or install structural components in the battery that are electrically connected to each battery cell to fully Utilize the space in the first pole to improve the space utilization rate and volumetric energy density of the battery; by setting the first groove, the first cover plate covers the notch of the first groove, which facilitates the welding of the first cover plate. Improve assembly efficiency.

In addition, since the first pole has both a first receiving groove and a first groove, the first groove is located on a side of the first receiving groove away from the active material coating part, and the first groove faces away from the first receiving groove. The direction of the groove is open, thereby facilitating laser welding of the conductive part and the first end wall through the first groove from the outside of the first pole, that is, the side of the first pole away from the active material coating part, so as to facilitate The electrical connection between the conductive part and the first pole is achieved through external welding. That is to say, the above structural arrangement facilitates external welding of the first pole and the conductive part through the first groove, facilitates the processing and manufacturing of the battery cells, and can save processing and manufacturing costs.

In some embodiments, the active material coating part includes a current collector and an active material layer disposed on the current collector, and the conductive part includes a tab part electrically connected to the current collector, and the tab part includes a plurality of tabs, and the plurality of poles. The tabs converge near the current collector to form a first gathered part, and the plurality of pole tabs gather and connect at positions far away from the current collector to form a second gathered part. The first gathered part connects the second gathered part and the active material coating part. At least part of the two gathered parts is accommodated in the first receiving groove, and the second gathered part is connected to the first end wall through the first welding part.

In the above technical solution, since the pole tab portion includes a second gathered portion formed by gathering and connecting a plurality of pole tab pieces, at least part of the second gathered portion is accommodated in the first receiving groove, which facilitates the connection between the conductive portion and the first pole post. The connection can make full use of the space of the first pole and improve the volumetric energy density of the battery cell. When the second gathered portion and the first end wall are electrically connected through the first welding portion, such as when the second gathered portion is welded (for example, laser welded) to the first end wall, the structure of the battery core assembly can be simplified, reducing parts and simplifying Assembly process and improve assembly efficiency.

In some embodiments, the active material coating part includes a current collector and an active material layer provided on the current collector, the conductive part includes a tab part and an adapter piece, the tab part includes a plurality of tab pieces, and the plurality of tab pieces The positions close to the current collector gather to form a first gathered part, and the plurality of pole tabs gather and connect at positions far away from the current collector to form a second gathered part. The first gathered part connects the second gathered part and the active material coating part, and the adapter piece Connected to the second gathering part, at least part of the adapter piece is accommodated in the first receiving groove, and the adapter piece is connected to the first end wall through the first welding part.

In the above technical solution, on the one hand, by housing at least part of the adapter piece in the first receiving groove, the space in the first pole can be more fully utilized, further reducing the space occupied by the conductive part in the housing, so as to Improve the volumetric energy density of battery cells. On the other hand, by using the adapter piece and the first welding part to realize the indirect electrical connection between the second gathered part and the first pole, the adapter piece can be welded to the first pole using a part that avoids the second gathered part, so that The adapter piece and the first pole are welded firmly, the risk of welding cracking is small, and the reliability and stability of the battery cell can be further improved. At the same time, the first pole and the tab piece are electrically connected through the adapter piece. The structure of the pole tab can be simplified.

In some embodiments, at least part of the first gathering portion is received in the first receiving groove.

In the above technical solution, at least part of the first gathered portion of the pole lug is accommodated in the first receiving groove, which can more fully utilize the space in the first pole and further reduce the space occupied by the pole lug in the housing. In order to accommodate the larger-sized active material coating part, the volume energy density of the battery cell is increased, and the redundancy of the tab part in the case can be better reduced, further reducing the distance between the tab part and the active material coating part. Chance of short circuit.

In some embodiments, the housing has a mounting hole, and the first pole is installed in the mounting hole; along the axial direction of the first pole, the depth H1 of the first receiving groove is greater than or equal to the minimum distance from the inner end surface of the pole to the mounting hole. H2.

In the above technical solution, since in the axial direction of the first pole, the depth H1 of the first receiving groove is greater than or equal to the minimum distance H2 from the inner end surface of the pole to the mounting hole, the volume of the first pole can be fully utilized, so that The first accommodating groove has a larger depth, which is conducive to accommodating more conductive parts, thereby reducing the space occupied by the conductive parts in the case to a greater extent, further increasing the energy density of the battery cell, and further reducing the space occupied by the conductive parts. Redundancy in the casing; at the same time, because the first accommodation tank has a large depth, it can also accommodate the gas produced by the battery core assembly, ensuring the reliability and stability of the battery cells, and can also accommodate more electrolyte to ensure Ensure the service life of the battery cells.

In some embodiments, the pole body has a second receiving groove. The surface of the pole body on the side away from the active material coating part is the pole outer end surface. The notch of the second receiving groove is formed on the pole outer end face. The second The accommodating groove has a second end wall close to the active material coating part, the first welding part is provided on the second end wall, the first cover plate cooperates with the pole body and covers the slot of the second accommodating groove.

In the above technical solution, on the one hand, the first pole is provided with a second accommodation groove, which can reduce the weight of the first pole to a certain extent and improve the weight energy density of the battery cell and battery; on the other hand, due to the second accommodation groove, The notch is formed on the outer end surface of the pole, and the outer end surface of the pole is the surface of the first pole away from the active material coating part, so that the second receiving groove can be opened in the direction away from the active material coating part. In this way, when at least part of the conductive part is accommodated in the second accommodating groove, the conductive part can be easily stored and arranged through the slot of the second accommodating groove, and the conductive part can be easily stored and arranged through the groove of the second accommodating groove. The port realizes the electrical connection operation between the conductive part and the first pole, thereby reducing the production difficulty of the battery cells and improving the production efficiency of the battery cells. Wherein, the first welding part is provided on the second end wall, that is to say, the second accommodating groove not only has the function of accommodating at least part of the conductive part, but the groove wall of the second accommodating groove also has the function of welding with the conductive part. The structure of the first pole can be simplified and the processing of the first pole can be facilitated. Moreover, the opening direction of the slot of the second accommodating groove makes it easy to weld the conductive part and the groove wall of the second accommodating groove through the slot of the second accommodating groove, which can reduce the difficulty of welding and utilize the second accommodating groove. The groove wall realizes the welding connection with the conductive part, which can make the welding area formed by the first welding part between the conductive part and the first pole relatively large, improve the reliability and stability of the electrical connection, and thereby improve the battery cell performance.

Furthermore, since the conductive part is connected to the pole body through the first welding part, there is welding slag at the first welding part. The first welding part is provided on the second end wall, so that the welding slag can be kept away from the active material coating. The covering part can reduce the amount of welding slag entering the inside of the shell. On the other hand, the first cover plate blocking the first welding part can protect the first welding part, so that the welding slag or part falling on the first welding part The welding slag can be blocked by the first cover plate, further reducing the amount of welding slag entering the inside of the case. By twice reducing the amount of welding slag entering the case, the risk of short circuit caused by the presence of welding slag inside the battery cell can be greatly reduced. Improve the reliability of battery cells.

In addition, when the battery cell transmits electricity to the outside, the pole body needs to be electrically connected to the bus part. At this time, the pole body and the bus part are welded. In this case, since the first cover can block the first welding part, that is, The bus part can be prevented from contacting the first welding part, or it can be understood that the bus part and the first welding part can be isolated from each other, which can also reduce the influence of the first welding part on other welding positions on the pole body.

In some embodiments, the conductive portion is located on a side of the second end wall facing the active material coating portion.

In the above technical solution, the first welding part is provided on the side of the second end wall facing the active material coating part. At this time, the distance between the first welding part and the surface of the pole body located outside the housing is relatively far. , which can reduce the impact of high temperature on the first welding part caused by the welding of the pole body and the bus component.

In some embodiments, the second receiving groove is connected to the interior of the housing through the first through hole, the conductive portion is disposed through the first through hole and is at least partially accommodated in the second receiving groove, and the conductive portion is at least partially disposed on the second end wall. The side facing away from the active material coating part.

In the above technical solution, since the second accommodating tank can be connected with the interior of the casing through the first through hole, the second accommodating tank can also serve as a buffer and temporary storage structure for the electrolyte, so that more electrolyte can be accommodated in the casing. , since the battery cell will lose electrolyte during the charging and discharging process, when there is more electrolyte, the service life of the battery cell can be extended; and also because the second accommodation tank can be connected with the interior of the casing through the first through hole, The second accommodation groove can also be used as an accommodation and buffer structure for the gas produced inside the battery cell assembly, reducing the expansion of the battery cells and improving the reliability and stability of the battery cells.

In some embodiments, the second containing groove further has a second side wall, the second side wall is located on a side of the second end wall away from the active material coating part, and the second side wall and the second end wall surround and form a third Two receiving grooves, the first through hole is opened in the second end wall, the second end wall has a second sinking groove, and at least part of the first welding part is located in the second sinking groove.

In the above technical solution, on the one hand, since the first perforation is opened in the second end wall, it is convenient for the conductive part to extend into the second receiving groove through the first perforation, which can simplify the structure of the conductive part, reduce the redundancy of the conductive part, and reduce the cost of the conductive part. the cost of. On the other hand, the part of the first welding part located in the second sinking groove is set to match the shape of the second sinking groove and are closely arranged to achieve electrical connection, so that the second sinking groove can be used to electrically connect the conductive part. The pre-positioning and limiting of the connection position is conducive to finding the correct position for electrical connection, improving production efficiency, and improving the stability and reliability of the electrical connection position to ensure the reliability and stability of the battery cell charging and discharging operations.

In some embodiments, the active material coating part includes a current collector and an active material layer disposed on the current collector, and the conductive part includes a tab part electrically connected to the current collector, and the tab part includes a plurality of tabs, and the plurality of poles. The tabs converge near the current collector to form a first gathered part, and the plurality of pole tabs gather and connect at positions far away from the current collector to form a second gathered part. The first gathered part connects the second gathered part and the active material coating part. At least part of the two gathered parts is accommodated in the second receiving groove, and the second gathered part is connected to the second end wall through the first welding part.

In the above technical solution, since the pole tab portion includes a plurality of pole tab pieces gathered and connected to form a second gathered portion, at least part of the second gathered portion can be easily accommodated in the second receiving groove, which facilitates the connection between the conductive portion and the third One pole welding. Secondly, by accommodating at least part of the second gathering portion in the second accommodating groove, the space in the first pole can be used to reduce the space occupied by the conductive portion in the case and improve the volumetric energy density of the battery cell.

In some embodiments, the active material coating part includes a current collector and an active material layer provided on the current collector. The conductive part includes a tab part and an adapter piece. The tab part is electrically connected to the current collector. The tab part includes a plurality of A plurality of pole tabs converge at a position close to the current collector to form a first gathered portion, and a plurality of pole tabs gather at a position far away from the current collector and are connected to form a second gathered portion, and the first gathered portion connects the second gathered portion and the In the active material coating part, the adapter piece is connected to the second gathering part, at least part of the adapter piece is accommodated in the second receiving groove, and the adapter piece is connected to the second end wall through the first welding part.

In some embodiments, at least part of the first gathering portion is received in the second receiving groove.

In the above technical solution, by accommodating at least part of the first gathering part and the adapter piece in the second accommodating groove, the space in the first pole can be more fully utilized and the space occupied by the conductive part in the housing can be further reduced. , to further improve the volumetric energy density of the battery cells. Moreover, by arranging the adapter piece of the sheet structure, it is convenient for the adapter piece to extend into the second receiving groove through the first through hole.

In some embodiments, the pole body is provided with a first accommodation portion, the first accommodation portion has a third accommodation groove, the surface of the first pole facing the active material coating portion is the inner end surface of the pole, and the third accommodation groove is located at The side of the second accommodating groove close to the active material coating part, and the notch of the third accommodating groove is formed on the inner end surface of the pole, the third accommodating groove and the second accommodating groove are connected through the first through hole, and the first gathering part At least part of is accommodated in the third receiving groove.

In the above technical solution, at this time, part of the conductive part is located in the third receiving groove, and at the same time, the conductive part is also penetrated through the first through hole, and the remaining part of the conductive part is located in the second receiving groove, so that it can be fully utilized. The space within the first pole reduces the space occupied by the conductive part in the housing.

In some embodiments, the housing assembly further includes a second cover plate, and the second cover plate covers the first through hole and the conductive portion located in the second receiving groove.

In the above technical solution, at least part of the conductive part is located in the second receiving groove, the second cover plate covers this part of the conductive part, and the second cover plate also covers the first through hole, so that when the electrolyte flows from the first through hole Entering the second accommodation tank, the problem of overflowing of this part of the electrolyte from the first pole can be improved through the second cover plate, thereby improving the reliability of the battery cells.

In some embodiments, the housing has a mounting hole, and the first pole is installed in the mounting hole. Along the axial direction of the first pole, the depth H3 of the second receiving groove is greater than or equal to the minimum distance from the outer end surface of the pole to the mounting hole. H4.

In the above technical solution, the depth H3 of the second receiving groove refers to the maximum depth of the second receiving groove along the axial direction of the first pole. Since in the axial direction of the first pole, the depth H3 of the second accommodation groove is greater than or equal to the minimum distance H4 from the outer end surface of the pole to the mounting hole, the volume of the first pole can be fully utilized, so that the second accommodation groove has A larger depth is conducive to accommodating more conductive parts, thereby reducing the space occupied by the conductive parts in the case to a greater extent, further increasing the energy density of the battery cells, and further reducing the redundancy of the conductive parts in the case. ; At the same time, because the second accommodation tank has a larger depth, it can also accommodate the gas produced by the battery cell assembly to ensure the reliability and stability of the battery cells. It can also accommodate more electrolyte to ensure the stability of the battery cells. service life.

In some embodiments, the pole body is provided with a first accommodating part, the first accommodating part has a fourth accommodating groove, the surface of the pole body on the side away from the active material coating part is the outer end surface of the pole, and the groove of the fourth accommodating groove is The opening is formed on the outer end face of the pole, the fourth receiving groove is connected with the interior of the housing through the second through hole, the conductive part is provided in the second through hole, and the first welding part is provided in the second through hole formed in the first receiving part. On the wall, the first cover plate cooperates with the pole body and covers the second through hole.

In the above technical solution, the welding of the conductive part and the hole wall of the second through hole can be easily realized by providing the fourth receiving groove. Moreover, in some cases, the electrical connection between the conductive part and the first pole can be used to achieve sealing of the second through hole. For example, the conductive part and the hole wall of the second through hole can be welded at the position where the second through hole is connected to the fourth receiving groove, so as to facilitate the operation, and the welding mark and the conductive part can be realized by controlling the welding mark. The second through hole is sealed to improve the problem of the electrolyte in the housing leaking from the second through hole.

In some embodiments, the pole body includes a first pole part and a second pole part that are made of different materials and are electrically connected. The second pole part is located on a side of the first pole part away from the active material coating part. A receiving part is provided on the first pole part or on the first pole part and the second pole part, and the first welding part is provided on the first pole part.

In the above technical solution, by arranging the first pole in a composite form composed of different materials, the first pole part located on the inside is accommodated, matched and electrically connected with the conductive part, and the second pole located on the outside is used. The electric connection between the first pole and the bus part is facilitated, thereby facilitating the assembly and electrical connection of the first pole and related parts, reducing the welding positions of the first pole and the conductive part, and the welding positions of the first pole and the bus part of the battery. The mutual interference between them improves the reliability and stability of the battery cells.

In some embodiments, the first cover plate is provided with a second accommodating portion, the second accommodating portion has a fifth accommodating groove, and the notch of the fifth accommodating groove is formed on an end surface of the first cover plate facing the active material coating portion. , and the fifth accommodation groove has a third end wall and a third side wall, the third end wall is located on a side of the third side wall away from the active material coating part, and at least part of the first welding part is accommodated in the fifth accommodation groove Inside.

In the above technical solution, on the one hand, the first cover plate is provided with the fifth receiving groove, which can reduce the weight of the first pole to a certain extent and improve the weight energy density of the battery cell and battery; on the other hand, due to the fifth The notch of the receiving groove is formed on an end surface of the first cover plate facing the active material coating portion, and the third end wall is located on a side of the third side wall away from the active material coating portion, so that the fifth receiving groove It can be opened in a direction away from the active material coating part, so that when at least part of the conductive part is accommodated in the fifth accommodation groove, the first welding part can be easily accommodated through the notch of the fifth accommodation groove. Sorting can reduce the difficulty of producing battery cells and improve the production efficiency of battery cells.

In some embodiments, the first cover is electrically connected to the pole body; or, the first cover is insulated from the pole body.

In the above technical solution, the first cover plate can be electrically connected to the pole body. At this time, the first cover plate can also participate in the bus component for electrical connection, which can increase the area of the weldable area and facilitate the connection between the first pole and the bus component. welding. The first cover plate may not be electrically connected to the pole body, that is, the two are insulated. In this case, the first cover plate mainly functions to protect the first welding part.

In some embodiments, the first cover plate includes a first conductive member and a second conductive member made of different materials. The first conductive member cooperates with and is electrically connected to the pole body, and the second conductive member cooperates with and is electrically connected to the first conductive member.

In the above technical solution, the first cover plate is set in a composite form, and the first conductive member is made of the same material as the first pole, thereby facilitating the electrical connection between the first conductive member and the first pole. For example, it can be easily The first conductive member and the first pole are reliably and stably connected easily through welding. Moreover, since the materials of the second conductive member and the first conductive member are different, it is convenient to use the second conductive member to make electrical connections with bus parts whose materials are different from those of the first pole. For example, the second conductive member and the material can be easily connected by welding. The bus part that is the same as the second conductive part is connected reliably and stably.

In some embodiments, the first conductive member has a second groove, the second conductive member is embedded in the second groove, and the notch of the second groove is formed on a side of the first conductive member away from the active material coating part. on the surface, so that the second conductive member is exposed from the notch of the second groove.

In the above technical solution, on the one hand, by embedding the second conductive member in the first conductive member, the assembly difficulty of the first conductive member and the second conductive member can be reduced, and the cooperation between the first conductive member and the second conductive member can be improved. The stability and convenience of the battery cell can be reduced, and the thickness of the first cover plate can be reduced, thereby reducing the space occupied by the first cover plate, thereby improving the space utilization of the battery cells. On the other hand, since the second conductive member can be exposed from the surface of the first conductive member away from the second receiving groove through the notch of the second groove, it is beneficial to realize that the second conductive member is connected to the outside of the first pole. The bus parts are electrically connected.

In addition, since the notch of the second groove is formed on the surface of the first conductive member on the side away from the second receiving groove, it means that the second groove is open toward the direction away from the active material coating portion, so that the first conductive member A portion of the groove wall defining the second groove is located between the second receiving groove and the second conductive member to separate the second receiving groove and the second conductive member, thereby preventing electrolysis entering the second groove. The liquid contacts the second conductive member to reduce leakage of electrolyte.

In some embodiments, the first cover plate has a stress relief groove, and the stress relief groove is located in a peripheral area of the first cover plate.

In the above technical solution, by providing a stress relief groove on the first cover plate, the stress generated during the processing of the first cover plate itself or during the electrical connection between the first cover plate and the first pole can be released to improve the performance of the first cover plate. Problems related to deformation or damage of the first cover due to stress.

In some embodiments, the battery cell further includes: a bracket located in the housing and on a side of the active material coating part close to the first pole, the bracket has an escape hole for avoiding the conductive part, and the conductive part is suitable for Extend through the avoidance hole to the side of the stent away from the active material coating part.

In the above technical solution, by providing a bracket on the side of the active material coating part close to the first pole, the bracket can be used to separate the active material coating part from the case, thereby improving the reliability of the battery cell, and Providing an escape hole on the bracket can guide and constrain the conductive part to cooperate with the first pole by passing through the escape hole, so that there is no need for the conductive part to go around the edge of the bracket to approach the first pole, which not only simplifies the installation of the conductive part The arrangement saves the material of the conductive part and reduces the cost. The bracket can also support and guide the conductive part to cooperate with the first pole, which can reduce the risk of short-circuit connection between the conductive part and the active material coating part, so as to further improve the performance of the battery cells. reliability.

In some embodiments, the pole body is provided with a first receiving portion, the bracket is provided with a guide portion, the guide portion surrounds at least part of the escape hole, and the guide portion at least partially extends to the first receiving portion.

In the above technical solution, the guide part protrudes from the bracket and extends into the first receiving part, and at least part of the escape hole is formed in the guide part, so that when the conductive part is inserted through the escape hole, at least part of the conductive part can be easily stored into the first receiving part, thereby improving the assembly efficiency of the conductive part; at the same time, through the arrangement of the guide part, the cooperation between the bracket and the first pole, and between the bracket and the conductive part is closer and more reliable, so that the battery unit The structure of the battery is more compact, which is more conducive to improving the energy density of the battery cell.

In some embodiments, the avoidance hole includes a first hole segment and a second hole segment, the second hole segment is located on a side of the first hole segment close to the active material coating part, and the cross-sectional area of the second hole segment is along the distance away from the The direction of the first hole section gradually increases. The active material coating part includes a current collector and an active material layer provided on the current collector. The conductive part includes a tab part that is electrically connected to the current collector. The tab part includes a plurality of tabs. A plurality of pole tabs converge at a position close to the current collector to form a first gathered portion, a plurality of pole tabs gather at a position far away from the current collector and are connected to form a second gathered portion, and the first gathered portion connects the second gathered portion and the active material In the coating part, at least part of the first gathered part is accommodated in the second hole section, and the second gathered part penetrates the first hole section.

In the above technical solution, by setting the escape hole to include a second hole section that gradually expands toward the direction of the active material coating part, it is convenient for the second hole section to accommodate more first gathering parts, and the bracket and the battery core assembly are improved. The compactness of the combination makes the overall volume of the battery cells smaller, allowing the battery to accommodate a larger number of battery cells, thereby increasing the volumetric energy density of the battery.

In some embodiments, the bracket is an integrated structure; or, the bracket is a split structure and includes a detachable first bracket and a second bracket, and an escape hole is defined between the first bracket and the second bracket.

In the above technical solution, the escape hole is formed in the form of a through hole penetrating the bracket. Therefore, the bracket with an integrated structure is easy to process and has good reliability. It also facilitates the assembly of the bracket and the housing assembly, improving assembly efficiency and coordination stability. When the bracket has a split structure, the bracket includes a detachable first bracket and a second bracket. Both the first bracket and the second bracket are long plate-like structures, and the two can be detachably connected, for example, the two can be plugged in. Or snap fit for easy assembly. An escape hole is defined through the cooperation of the first bracket and the second bracket. When the bracket is assembled with the battery core assembly, there is no need to pass the conductive part from one end of the escape hole to the other end. Instead, the first bracket and the second bracket can be placed between the first bracket and the second bracket. The position of the conductive part is combined to clamp the conductive part, so that the avoidance hole surrounds the conductive part, thereby facilitating the assembly of the bracket and the battery core assembly and improving the assembly efficiency.

In some embodiments, the housing has a first wall, and a mounting hole is formed on the first wall. The pole body is disposed in the mounting hole. The plane where the cross section of the mounting hole is located is the projection plane. Along the direction perpendicular to the projection plane, the first The ratio of the projected area of the welding portion on the projection plane to the projected area of the first wall on the projection plane is in the range of 0.1% to 1%.

In the above technical solution, by setting the ratio of the projected area of the first welding part on the projection surface to the projected area of the first wall on the projection surface to be within the range of 0.1% to 1%, the relationship between the conductive part and the pole body is improved. The effective flow area between the two poles increases the flow area of the first pole and improves the overcurrent capacity of the first pole, which is beneficial to increasing the charging speed of the battery cell and, to a certain extent, is also beneficial to improving the first pole The thermal diffusion capacity of the column reduces the overflow temperature of the first pole, which is beneficial to reducing the risk of battery cells running out of control.

In some embodiments, the housing has a mounting hole, and the pole body includes an integrally formed pole body part, a first limiting platform part, and a second limiting platform part. The pole body part passes through the mounting hole, and the first limiting platform part The positioning platform part and the second limiting platform part are arranged on both ends of the main body of the pole along the axial direction of the mounting hole. The first limiting platform part is limitedly fitted to the outside of the housing, and the second limiting platform part is limited in position. Fitted to the inside of the casing so that the pole body is riveted to the casing.

In the above technical solution, the first limiting platform portion and the second limiting platform portion respectively extend along the radial direction of the mounting hole to the radial outer side of the peripheral wall of the mounting hole, and the first limiting platform portion can limit the position of the first pole. The movement of the first pole relative to the housing in the direction toward the inside of the housing, and the second limiting platform portion can limit the movement of the first pole relative to the housing in the direction toward the outside of the housing, thereby making it easier for the first pole to pass The first limiting platform part and the second limiting platform part are reliably installed at the installation hole to achieve a fixed connection between the first pole and the housing, which facilitates the assembly of the first pole and the housing, and the first pole is connected to the housing. There is no need to use other connection methods between the housings, which can facilitate the reliable connection between the first pole and the housing, simplify the structure of the housing assembly, and simplify the assembly process of the housing assembly.

Moreover, since the pole body, the first limiting platform and the second limiting platform are integrally formed, parts can be saved, costs can be reduced, and the strength of the first pole can be ensured, so that the first pole is in contact with the shell. After the body is matched, it is not easy for the first pole to separate from the case due to vibration or external pulling during the charging and discharging process of the battery cell, and it is also not easy to be cracked or damaged due to vibration or external pulling, which can improve the stability and reliability of the case assembly. , thereby improving the stability and reliability of the battery cells.

In some embodiments, the battery cell further includes: an outer insulating member, and the outer insulating member is wrapped outside the casing. In the above technical solution, the outer insulating member plays an insulating role and is used to separate the housing from the external components and play an insulating role. For example, the outer insulation is blue film.

In some embodiments, the housing has a first wall, the first wall is formed with a mounting hole, the pole body is disposed in the mounting hole, the battery cell further includes a patch covering the outside of the first wall, and the outer insulating member includes an outer insulating member. film, the outer insulating film is an integrated diaphragm, and the outer insulating film has a connecting portion, and the connecting portion extends to the outside of the first wall and is connected to the patch.

In the above technical solution, the connecting portion can be overlapped with the patch along the axial direction of the mounting hole to facilitate the connection between the connecting portion and the patch. At this time, the outer insulating film and the patch can at least connect the first pole on the first wall. The column and the case are separated to improve the insulation reliability between the first pole and the case, thereby improving the reliability of the battery cell. For example, the connecting portion can extend in an annular shape around the outer periphery of the first wall, so that the outer insulating member can be wrapped around all other walls of the housing except the first wall. The connecting portion can be provided between the patch and the first wall to facilitate This makes the patch play a certain protective role in the connection between the connecting part and the patch.

In some embodiments, the minimum distance between the edge of the outer insulating film and the first pole is greater than or equal to 3 mm. In this technical solution, the creepage distance between the first pole and the casing can be greater than or equal to 3 mm, which is beneficial to improving the insulation withstand voltage performance between the first pole and the casing.

In a second aspect, embodiments of the present application provide a battery, including the aforementioned battery cell.

In the above technical solution, by locating the first welding portion of the battery cell at least partially on the side of the pole body away from the active material coating portion, the first welding portion can be kept away from the active material coating portion. When the pole body and When the conductive part is welded at high temperature to form the first welding part, since the first welding part serves as a high-temperature heat source and can be far away from the active material coating part, the impact of the high temperature generated by welding on the active material coating part can be reduced and the active material coating part can be reduced. The probability of being damaged increases the reliability of battery cells. In addition, after the pole body is welded to the conductive part inside the casing, when the battery cell is welded to the bus part, the first cover plate blocks the first welding part, which can play a protective role and weaken the power when the pole body is welded to the bus part. The impact of the generated high temperature on the first welding part improves the reliability of the first welding part between the pole body and the conductive part. It can be seen that by arranging a battery including the above battery cells, the reliability of the battery can be improved.

In some embodiments, the battery further includes: a plurality of battery cells; a bus component, the bus component is electrically connected to the first poles of at least two battery cells, and the first poles of the same polarity of each battery cell are respectively The second welding part is electrically connected to the bus component, and the second welding part is formed on the first cover plate; wherein, the housing includes a first wall, a mounting hole is formed on the first wall, and the pole body is disposed in the mounting hole. On the cross-section of the hole, the orthogonal projected area of the second welding portion is greater than or equal to 0.2% of the orthogonal projected area of the first wall.

In the above technical solution, by arranging the orthogonal projected area of the second welding portion between the bus component and the corresponding first pole on the cross section of the mounting hole to be greater than or equal to 0.2% of the orthogonal projected area of the first wall, so that The effective flow area between the bus part and the corresponding first pole is greater than or equal to 0.2% of the orthographic projection area of the first wall, so as to increase the effective flow area between the bus part and the first pole, and improve the flow of the first pole. The flow area increases the overcurrent capacity of the first pole, which is beneficial to increasing the charging speed of the battery cell. It also helps to improve the heat diffusion capacity of the first pole to a certain extent and reduces the overcurrent temperature of the first pole. , which is conducive to reducing the risk of battery cells losing control.

In some embodiments, along the direction perpendicular to the cross-section of the mounting hole, the overlapping portion of the bus component with the pole body of the same polarity is the weldable area of the bus component, and the second welding portion is in the positive direction of the cross-section of the mounting hole. The projected area is greater than or equal to 0.2 of the weldable area area of the bus component.

In the above technical solution, that is, the weldable area of the bus component overlaps with the pole body in the direction perpendicular to the projection plane, or in other words, in the direction perpendicular to the projection surface, the weldable area of the bus component is in the cross section of the mounting hole. The projection on at least partially overlaps with the projection of the pole body on the cross section of the mounting hole; then the weldable area of the bus component can be understood as the area provided by the bus component that can be welded to the pole body, then the weldable area The area must be greater than or equal to the orthogonal projected area of the second welding part on the projection plane. Then the projected area of the second welding part on the projection surface has an appropriate proportion, so as to facilitate the welding operation between the bus component and the pole body on the premise of appropriately improving the current flow capacity and heat diffusion capacity of the pole body.

In some embodiments, along the direction perpendicular to the cross-section of the mounting hole, the overlapping portion of the bus component with the first pole of the same polarity is the weldable area of the bus component, and the area of the weldable area of the bus component is greater than or equal to 20% of the orthogonal projected area of the manifold component on the cross-section of the mounting hole.

In the above technical solution, the weldable area of the bus component overlaps with the first pole of the same polarity in a direction perpendicular to the cross-section of the mounting hole, or in other words, in a direction perpendicular to the cross-section of the mounting hole, the bus component The orthographic projection of the weldable area on the cross section of the mounting hole at least partially overlaps with the orthographic projection of the first pole of the same polarity on the cross section of the mounting hole; then the weldable area of the bus component can be understood as the bus component provides The area that can be welded to the first pole, then the area of the weldable area of the bus component must be greater than or equal to the orthogonal projected area of the second welding part on the cross section of the mounting hole. The area of the weldable area of the bus component is greater than or equal to 20% of the orthogonal projected area of the bus component on the cross section of the mounting hole. This allows the bus component to provide sufficient weldable area to lay the foundation for improving the flow capacity and heat diffusion capacity of the first pole.

In some embodiments, the area of the weldable area of the bus component is less than or equal to 50% of the orthogonal projected area of the bus component on the cross-section of the mounting hole.

In the above technical solution, by setting the area of the weldable area of the bus component to be greater than or equal to 50% of the orthogonal projected area of the bus component on the cross section of the mounting hole, it is conducive to further balancing the overcurrent capacity of the first pole and the welding operation. Convenience.

In a third aspect, embodiments of the present application provide an electrical device, including the aforementioned battery.

Description of the drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application and therefore do not It should be regarded as a limitation of the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without exerting creative efforts.

Figure 1 is a schematic structural diagram of a vehicle provided by some embodiments of the present application;

Figure 2 is an exploded view of the structure of a battery provided by some embodiments of the present application;

Figure 3 is a schematic structural diagram of a battery cell provided by some embodiments of the present application;

Figure 4 is a front projection view of a battery cell provided by some embodiments of the present application;

Figure 5 is a cross-sectional view along line A-A in Figure 4;

Figure 6 is a schematic structural diagram of a battery cell provided by some embodiments of the present application;

Figure 7 is an assembly diagram of the second pole, battery core assembly and casing provided by some embodiments of the present application;

Figure 8 is a partial cross-sectional schematic diagram of a battery cell provided by some embodiments of the present application;

Figure 9 is a partial cross-sectional schematic diagram of a battery cell provided by some embodiments of the present application;

Figure 10 is a partial cross-sectional schematic diagram of a battery cell provided by some embodiments of the present application;

Figure 11 is a partial cross-sectional schematic view of a battery core assembly provided by some embodiments of the present application;

Figure 12 is a diagram of various tab retracting schemes of the battery core assembly provided by some embodiments of the present application;

Figure 13 is a partial cross-sectional schematic diagram of a battery cell provided by some embodiments of the present application;

Figure 14 is a partial cross-sectional schematic diagram of a battery cell provided by some embodiments of the present application;

Figure 15 is a partial cross-sectional schematic diagram of a battery cell provided by some embodiments of the present application;

Figure 16 is a partial cross-sectional schematic diagram of a battery cell provided by some embodiments of the present application;

Figure 17 is a partial cross-sectional schematic diagram of a battery cell provided by some embodiments of the present application;

Figure 18 is a partial enlarged view of B in Figure 3;

Figure 19 is an orthographic view of various first poles provided by some embodiments of the present application;

Figure 20 is a partial cross-sectional schematic diagram of a battery cell provided by some embodiments of the present application;

Figure 21 is a partial cross-sectional schematic view of a battery cell provided by some embodiments of the present application;

Figure 22 is a partial cross-sectional schematic diagram of a battery cell provided by some embodiments of the present application;

Figure 23 is an exploded view of the structure of a battery cell provided by some embodiments of the present application;

Figure 24 is a partial cross-sectional schematic view of a housing assembly provided by some embodiments of the present application;

Figure 25 is an exploded view of the structure of the housing assembly shown in Figure 24;

Figure 26 is an exploded view of the structure of the first cover plate shown in Figure 25;

Figure 27 is a partial cross-sectional schematic diagram of a battery cell provided by some embodiments of the present application;

Figure 28 is an exploded view of the structure of the battery cell shown in Figure 27;

Figure 29 is a partial cross-sectional schematic view of a battery cell provided by some embodiments of the present application;

Figure 30 is a partial cross-sectional schematic diagram of a battery cell provided by some embodiments of the present application;

Figure 31 is a partial cross-sectional schematic diagram of a battery cell provided by some embodiments of the present application;

Figure 32 is a partial cross-sectional schematic diagram of a battery cell provided by some embodiments of the present application;

Figure 33 is a partial cross-sectional schematic diagram of a battery cell provided by some embodiments of the present application;

Figure 34 is a schematic diagram of the cooperation between the battery core assembly and the bracket provided by some embodiments of the present application;

Figure 35 is a cross-sectional view along line C-C in Figure 34;

Figure 36 is a schematic structural diagram of an integrated bracket provided by some embodiments of the present application;

Figure 37 is a schematic structural diagram of a split bracket provided by some embodiments of the present application;

Figure 38 is a partial cross-sectional schematic view of the battery core assembly and bracket provided by some embodiments of the present application;

Figure 39 is an exploded view of the structure of the battery core assembly, bracket, and case assembly provided by some embodiments of the present application;

Figure 40 is an exploded view of the structure of the first pole, housing and sealing gasket provided by some embodiments of the present application;

Figure 41 is an assembly diagram of the first pole, housing and sealing gasket shown in Figure 40;

Figure 42 is a schematic structural diagram of the first pole provided by some embodiments of the present application;

Figure 43 is an assembly diagram of the first pole, housing and sealing gasket provided by some embodiments of the present application;

Figure 44 is an exploded view of the structure of the first pole shown in Figure 43;

Figure 45 is a front projection view of a battery cell provided by some embodiments of the present application;

Figure 46 is a front projection view of a battery cell provided by some embodiments of the present application;

Figure 47 is a cross-sectional view along line D-D in Figure 46;

Figure 48 is a schematic cross-sectional view of a housing assembly provided by some embodiments of the present application;

Figure 49 is a schematic cross-sectional view of a housing assembly provided by some embodiments of the present application;

Figure 50 is an orthographic view of a battery cell provided by some embodiments of the present application;

Figure 51 is a cross-sectional view along line E-E in Figure 50;

Figure 52 is a partial cross-sectional schematic diagram of a battery cell provided by some embodiments of the present application;

Figure 53 is a schematic structural diagram of a shell cover provided by some embodiments of the present application;

Figure 54 is a partial schematic diagram of a battery cell provided by some embodiments of the present application;

Figure 55 is a partial schematic diagram 2 of a battery cell provided by some embodiments of the present application;

Figure 56 is a schematic diagram of a battery cell provided by an embodiment of the present application;

Figure 57 is a schematic diagram of the electrical connection between a battery cell and a bus component provided by an embodiment of the present application;

Figure 58 is a schematic diagram of the electrical connection between the bus component and the pole provided by an embodiment of the present application;

Figure 59 is a schematic diagram of the connection between the first polarity pole and the conductive part of the battery cell shown in Figure 56;

Figure 60 is a schematic diagram of the installation of the first polarity pole provided by an embodiment of the present application;

Figure 61 is a schematic diagram of the installation of the first polarity pole provided by an embodiment of the present application;

Figure 62 is a schematic diagram of the installation of the first polarity pole provided by an embodiment of the present application;

Figure 63 is a schematic diagram of the installation of the first polarity pole provided by an embodiment of the present application;

Figure 64 is a schematic diagram of the installation of the first polarity pole provided by an embodiment of the present application;

Figure 65 is a schematic diagram of the installation of the first polarity pole provided by an embodiment of the present application;

Figure 66 is a schematic diagram of a battery core assembly provided by an embodiment of the present application;

Figure 67 is a schematic diagram of the arrangement of the first polarity pole and the second polarity pole provided by an embodiment of the present application;

Figure 68 is a schematic diagram of the arrangement of the first polarity pole and the second polarity pole provided by an embodiment of the present application;

Figure 69 is a schematic diagram of the arrangement of the first polarity pole and the second polarity pole provided by an embodiment of the present application;

Figure 70 is a schematic diagram of the arrangement of the first polarity pole and the second polarity pole provided by an embodiment of the present application;

Figure 71 is a schematic diagram of the layout of the first polarity pole and the second polarity pole provided by an embodiment of the present application.

Figure 72 is a schematic diagram of the arrangement of the first polarity pole and the second polarity pole provided by an embodiment of the present application;

Figure 73 is a schematic diagram of the installation of the first polarity pole provided by an embodiment of the present application;

Figure 74 is a schematic diagram of a battery cell provided by an embodiment of the present application;

Fig. 75 is a schematic diagram of the connection between the outer insulating member and the patch shown in Fig. 74.

Attached:

icon:

Electric device 1000; battery 100; controller 200; motor 300;

The first direction Z; the second direction X; the third direction Y;

Axial direction R of the first pole;

Battery cell 10; box 20; first box 201; second box 202; bus part 30;

Shell component 1;

Shell 11; first wall 110; second wall 120; shell body 111; shell cover 112; mounting hole 113; branch hole 1131; second mounting hole 114;

The first polarity pole 12; the first polarity pole 12A; the second polarity pole 12B;

first receiving part 121;

The first receiving groove 12110; the first end wall 12111; the first sinking groove 12112; the first side wall 12113;

second receiving groove 12120; second end wall 12121; second sinking groove 12122; second side wall 12123;

First groove section 12124; second groove section 12125; guide slope 12126; step surface 12127;

first through hole 12130; third receiving groove 12140; fourth receiving groove 12150;

The second perforation 12160; the third perforation 12170;

The inner end face of the pole is 122; the outer end face of the pole is 123;

The first pole part 124; the second pole part 125;

first groove 126; spacer 127;

Stopping part 1281; penetration part 1282; flange part 1283; pole body 1201; pole body part 12a; first limiting platform part 12b; second limiting platform part 12c; first part 128; second part 129 ;

Part 1 1291; Part 2 1292;

First cover plate 13; first conductive member 131; second groove 1311; second conductive member 132; stress relief groove 133; second receiving portion 134; fifth receiving groove 1341; third end wall 13411; third side wall13412;

second cover plate 14; second pole 15; pressure relief part 16; escape groove 18;

first sealing gasket 191; second sealing gasket 192;

Battery core assembly 2; electrode assembly 2a;

Active material coating part 21; current collector 211; active material layer 212; conductive part 22;

The pole tab part 221; the pole tab piece 2211; the first gathering part 2212; the second gathering part 2213; the adapter piece 222;

Bracket 3; avoidance hole 31; first hole section 311; second hole section 312;

Guide part 32; first bracket 33; second bracket 34; shell entry guide surface 35;

Body part 36; extension part 37; third groove 38; positioning groove 39;

Inner insulation part 4; main body part 41; connection part 42;

Seal 6; first welding part 71; second welding part 72; insulating sealing component 8; insulating component 81; seal 82; patch 9.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are Apply for some of the embodiments, not all of them. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of this application.

Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the technical field of this application; the terms used in the specification of this application are only for describing specific implementations. The purpose of the examples is not intended to limit the application; the terms "including" and "having" and any variations thereof in the description and claims of the application and the above description of the drawings are intended to cover non-exclusive inclusion. The terms "first", "second", etc. in the description and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or priority relationship.

Reference in this application to "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of this phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

In the description of this application, it should be noted that, unless otherwise clearly stated and limited, the terms "installation", "connection", "connection" and "attachment" should be understood in a broad sense. For example, it can be a fixed connection, It can also be detachably connected or integrally connected; it can be directly connected or indirectly connected through an intermediate medium; it can be internal communication between two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

The term "and/or" in this application is just an association relationship describing related objects, indicating that there can be three relationships, for example, A and/or B, which can mean: A exists alone, A and B exist simultaneously, alone There are three situations B. In addition, the character "/" in this application generally indicates that the related objects are an "or" relationship.

In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of simplicity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length and width of the integrated device, are only illustrative illustrations and should not constitute any limitation to the present application. .

"Plural" appearing in this application means two or more (including two).

In this application, the battery cells may include lithium ion secondary batteries, lithium ion primary batteries, lithium-sulfur batteries, sodium lithium ion batteries, sodium ion batteries or magnesium ion batteries, etc., which are not limited in the embodiments of this application. The battery cell may be in the shape of a cylinder, a flat body, a rectangular parallelepiped or other shapes, and the embodiments of the present application are not limited to this. Battery cells are generally divided into three types according to packaging methods: cylindrical battery cells, square battery cells and soft-pack battery cells, and the embodiments of the present application are not limited to this.

The battery mentioned in the embodiments of this application refers to a single physical module including one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in this application may be a battery module or a battery pack. Battery modules generally include multiple battery cells. A battery pack generally includes a box for packaging one or more battery cells or one or more battery modules. The box can prevent liquid or other foreign matter from affecting the charging or discharging of the battery cells.

For example, a battery cell generally includes a case, a cell assembly and an electrolyte. The case is used to accommodate the cell assembly and the electrolyte. The case is provided with at least one positive pole and at least one negative pole. The battery core assembly includes one or more electrode assemblies. The electrode assembly is formed by laminating or winding positive electrode sheets, negative electrode sheets and isolation films.

The positive electrode sheet generally includes a positive electrode current collector and a positive electrode active material layer. The positive electrode active material layer is directly or indirectly coated on the positive electrode current collector. The positive electrode current collector that is not coated with the positive electrode active material layer protrudes from the coated positive electrode. The positive electrode current collector with the active material layer and the positive electrode current collector that is not coated with the positive electrode active material layer serve as positive electrode tabs. Multiple positive electrode tabs are stacked together and electrically connected to the positive electrode post. For example, a plurality of positive electrode tabs stacked together can be directly welded to the positive electrode post to form an electrical connection; or, the battery core assembly can also include a positive electrode adapter sheet, and the multiple positive electrode tabs stacked together are connected to the positive electrode post. One end of the positive electrode adapter piece is welded, and the other end of the positive electrode adapter piece is welded to the positive electrode pole, so that the positive electrode tab and the positive pole are electrically connected.

The negative electrode sheet generally includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is directly or indirectly coated on the negative electrode current collector. The negative electrode current collector that is not coated with the negative electrode active material layer protrudes from the coated negative electrode active material. The negative electrode current collector without the negative electrode active material layer serves as the negative electrode tab. Multiple negative electrode tabs are stacked together and electrically connected to the negative electrode post. For example, a plurality of negative electrode tabs stacked together can be directly welded to the negative electrode post to form an electrical connection; alternatively, the cell assembly can also include a negative electrode adapter sheet, and the multiple negative electrode tabs stacked together are connected to the negative electrode post. One end of the negative electrode adapter piece is welded, and the other end of the negative electrode adapter piece is welded to the negative electrode pole, so that the negative electrode tab and the negative electrode pole are electrically connected. The material of the isolation film is not limited, for example, it can be polypropylene or polyethylene.

At the same time, the battery cells mainly rely on the movement of metal ions between the positive and negative electrodes to work. Taking lithium-ion batteries as an example, the material of the positive electrode current collector can be aluminum, the material of the positive electrode active material layer can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganate, etc., and the material of the negative electrode current collector can be copper. The material of the negative active material layer may be carbon, silicon, or the like. During the charge and discharge process, Li+ intercalates and deintercalates back and forth between the two electrodes: during charging, Li+ is deintercalated from the positive electrode and embedded in the negative electrode through the electrolyte, and the negative electrode is in a lithium-rich state; during discharge, the opposite is true.

In recent years, new energy vehicles have developed by leaps and bounds. In the field of electric vehicles, power batteries, as the power source of electric vehicles, play an important and irreplaceable role. The battery is composed of a box and multiple battery cells contained in the box. Among them, batteries, as the core components of new energy vehicles, have high requirements in terms of safety and cycle life.

When manufacturing a battery cell in the related art, an active material layer is coated on a current collector and then cut to obtain a current collector coated with an active material layer (referred to as an active material coated part) and an uncoated part. The active material layer is composed of current collectors (marked as tabs), and then the positive and negative electrodes and separators are stacked or wound in sequence to obtain an electrode assembly. Multiple tabs in the electrode assembly are stacked to form an electrode. The lug part, the lug part itself forms a conductive part, or the lug part and the adapter piece are connected to form a conductive part, and the active material coating part and the conductive part form a battery core assembly. A pole is provided on the casing of the battery cell, and the surface of the pole facing the active material coating part is the inner end surface of the pole. In the related art, the conductive part is generally welded to the inner end face of the pole.

The inventor found that during the assembly process of the battery cell, the pole lug is first welded to the inner end face of the pole. Since the first welding part is located on the inner end face of the pole, close to the inside of the battery cell, the metal residue during the welding process is difficult to completely clean, resulting in residual The metal residue falls into the active material coating part and overlaps the pole piece of the opposite polarity, causing an internal short circuit in the battery cell and reducing the reliability of the battery cell; moreover, the pole tab will be welded to the pole during the welding process. High temperatures will be generated, which will cause the tabs to form solder marks. The high temperatures will burn the active material coating in the casing, causing the active material coating on the active material coating to be lost, thereby reducing the performance of the battery cells, without affecting the performance of the battery cells. It is beneficial to extend the service life of the battery cells; on the other hand, in the process of forming the battery cells, the poles of the battery cells need to be welded and connected to the poles of another battery cell through the busbar. High temperature will also be generated. At this time, the high temperature formed when the pole and the external bus component are welded will affect the welding part of the pole and the pole, which may easily cause the welding part to be melted again and become loose, thereby reducing the performance of the battery cell.

Based on the above considerations, in order to solve the problem of internal short circuit caused by metal residue produced by welding, the problem of high temperature damage to the active material coating part caused by the tab welding, and the problem of the battery cell poles during the process of assembling the battery cells into batteries. The inventor has conducted in-depth research on the problem of affecting the welding parts of pole tabs and poles when welding with bus components, and designed a battery cell that includes a case assembly and a cell assembly. The case assembly includes a case and a first pole. The first pole includes a pole body and a first cover plate. The pole body is installed on the housing, and the first cover plate is arranged on the pole body. The battery core assembly includes an active material coating part and a conductive part connected to the active material coating part. The active material coating part is accommodated in the housing, and the conductive part is connected to the pole body through the first welding part. By having the first welding part at least partially located on the side of the pole body away from the active material coating part, the metal residue generated during the welding process can be reduced from entering the battery cell, and the metal residue can be prevented from overlapping the positive and negative electrode plates to a certain extent, thereby preventing the metal residue from overlapping the positive and negative electrode plates. Reduce the possibility of internal short circuit in battery cells. By positioning the first welding portion away from the active material coating portion, the impact of the high temperature generated by welding on the active material coating portion can be reduced, and the probability that the active material coating portion is damaged can be reduced. In addition, after the pole body is welded to the conductive part inside the casing, when the battery cell is welded to the bus part, the first cover plate blocks the first welding part, which can play a protective role and weaken the power when the pole body is welded to the bus part. The impact of the generated high temperature on the first welding part improves the reliability of the first welding part between the pole body and the conductive part.

The batteries disclosed in the embodiments of the present application can be used in, but are not limited to, electrical devices such as vehicles, ships, or aircrafts. The power supply system of the electrical device can be composed of the battery disclosed in this application.

Embodiments of the present application provide an electrical device that uses a battery as a power source. The electrical device may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric vehicle, a ship, a spacecraft, etc. Among them, electric toys can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, electric airplane toys, etc., and spacecraft can include airplanes, rockets, space shuttles, spaceships, etc.

For the convenience of explanation, the following embodiments take the electric device 1000 as an example to introduce the structures of the electric device 1000, the battery 100 and the battery cell 10 in detail.

Please refer to FIG. 1 , which is a schematic structural diagram of a vehicle 1000 provided by some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. The battery 100 is disposed inside the vehicle 1000 , and the battery 100 may be disposed at the bottom, head, or tail of the vehicle 1000 . The battery 100 may be used to power the vehicle 1000 , for example, the battery 100 may serve as an operating power source for the vehicle 1000 . The vehicle 1000 may also include a controller 200 and a motor 300 . The controller 200 is used to control the battery 100 to provide power to the motor 300 , for example, for starting, navigating and driving the vehicle 1000 .

In some embodiments of the present application, the battery 100 can not only be used as an operating power source for the vehicle 1000 , but also can be used as a driving power source for the vehicle 1000 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000 .

Please refer to FIG. 2 , which is an exploded view of the structure of the battery 100 provided by some embodiments of the present application. The battery 100 includes a case 20 and a plurality of battery cells 10 , and the battery cells 10 are used to be accommodated in the case 20 . Among them, the box 20 is used to provide an assembly space for the battery cells 10, and the box 20 can adopt a variety of structures. In some embodiments, the box body 20 may include a first box body 201 and a second box body 202. The first box body 201 and the second box body 202 cover each other, and the first box body 201 and the second box body 202 are common. An assembly space for accommodating the battery cells 10 is defined. The second box body 202 can be a hollow structure with one end open, and the first box body 201 can be a plate-like structure. The first box body 201 is covered with the open side of the second box body 202, so that the first box body 201 and the second box body 202 can be connected to each other. The two box bodies 202 jointly define an assembly space; the first box body 201 and the second box body 202 can also be hollow structures with one side open, and the open side of the first box body 201 is covered with the second box body 202 Open side. Of course, the box 20 formed by the first box body 201 and the second box body 202 can be in various shapes, such as cylinder, rectangular parallelepiped, etc.

In the battery 100, multiple battery cells 10 can be connected in series, in parallel, or in mixed connection. Mixed connection means that the multiple battery cells 10 are connected in series and in parallel. Multiple battery cells 10 can be directly connected in series or in parallel or mixed together, and then the whole composed of multiple battery cells 10 can be accommodated in the box 20 ; of course, the battery 100 can also be multiple battery cells 10 First, the battery modules are connected in series, parallel, or mixed to form a battery module. Then, multiple battery modules are connected in series, parallel, or mixed to form a whole, and are accommodated in the box 20 . The battery 100 may also include other structures. For example, the battery 100 may further include a bus component for electrical connection between multiple battery cells 10 .

Please refer to FIG. 2 , which is a partial structural diagram of the battery 100 provided by some embodiments of the present application. The battery 100 includes multiple rows of battery cells 10 arranged along a first direction X, and each row of battery cells 10 includes a plurality of battery cells 10 arranged along a second direction Y. The first direction X and the second direction Y are the length direction and the width direction of the box 20 respectively, and the first direction X and the second direction Y are perpendicular to each other.

Each battery cell 10 may be a secondary battery or a primary battery; it may also be a lithium-sulfur battery, a sodium-ion battery or a magnesium-ion battery, but is not limited thereto. The battery cell 10 may be in the shape of a cylinder, a flat body, a rectangular parallelepiped or other shapes. For example, in FIG. 3 , the shape of the battery cell 10 is a rectangular parallelepiped. In the related art, a battery cell generally includes a casing and a battery cell assembly. The casing is provided with a positive pole and a negative pole. The battery cell assembly is located in the casing. The battery cell assembly generally includes at least two pole pieces. And one part is a positive electrode piece, and the rest is a negative electrode piece. The positive electrode piece is provided with a positive electrode tab, and the negative electrode piece is provided with a negative electrode tab. A separator is set between the positive electrode piece and the negative electrode piece. Among them, the positive electrode tab is electrically connected to the positive pole, and the negative electrode tab is connected to the negative electrode. The columns are electrically connected, and the housing is filled with electrolyte.

Please refer to Figures 3 to 5 of the accompanying drawings. This embodiment of the present application provides a battery cell 10, which includes a case assembly 1 and a battery core assembly 2. The housing assembly 1 includes a housing 11 and a first pole 12. The first pole 12 includes a pole body 1201 and a first cover 13. The pole body 1201 is installed on the housing 11, and the first cover 13 is provided on the pole. Column body 1201. The battery core assembly 2 includes an active material coating part 21 and a conductive part 22 connected to the active material coating part 21. The active material coating part 21 is accommodated in the housing 11, and the conductive part 22 is connected to the electrode through the first welding part 71. The column body 1201 is connected. The shape of the casing 11 is adjusted according to the type of the battery cell 10. The type of the battery cell 10 in the embodiment of the present application is not limited. For example, when the battery cell 10 is a square battery, the casing 11 is square. When the battery cell 10 is a cylindrical battery, the casing 11 is cylindrical. The embodiments of the present application are all described with the casing 11 being square as an example.

The housing 11 is provided with poles, and the poles are used for electrical connection with the battery cell assembly 2 to ensure the normal charging and discharging operations of the battery cells 10 . Generally, the number of poles is at least two, specifically at least one positive pole and at least one negative pole. For example, when the number of poles is two, one is a positive pole and one is a negative pole, respectively. It is electrically connected to the positive and negative output positions of the battery core assembly 2; for another example, when the number of poles is four, two can be positive poles and two can be negative poles. At this time, both positive poles are connected to the electric pole. The positive output position of the core component 2 is electrically connected, and the two negative electrode posts are electrically connected to the negative output position of the battery core component 2 .

At the same time, Figure 6 is a schematic structural diagram of the battery cell 10 provided by some embodiments of the present application; Figure 7 is an assembly diagram of the second pole 15, the cell assembly 2, and the housing 11 provided by some embodiments of the present application. Please refer to 1 to 7 , in the embodiment of the present application, at least one pole among the plurality of poles is a first pole 12 , and the first pole 12 can be used as either a positive pole or a negative pole.

Regardless of whether the pole on the housing 11 is the first pole 12 or the second pole 15 , the first pole 12 and the second pole 15 can be electrically connected to the battery assembly 2 to ensure the charging of the battery cell 10 . The discharge process proceeds normally. Of course, in other embodiments of the present application, the housing assembly 1 may also be provided with only one pole, and it is the first pole 12. The first pole 12 includes two parts, and the two parts are insulated and connected, and are respectively Just use the positive pole and the negative pole. To simplify the description, the following description will mainly take the example in which all the poles on the housing 11 are the first poles 12 formed with the receiving portions 121 .

It should be noted that, please refer to Figures 6 and 7, when the second pole 15 is provided on the housing 11, an escape groove 18 can be provided between the second pole 15 and the housing 11 as required, so that the conductive portion At least part of 22 is received in the escape groove 18 . This can also reduce the space occupied by the conductive portion 22 in the housing 11 to a certain extent, which is beneficial to increasing the energy density and improving problems such as short circuit caused by redundant conductive portions 22 .

Please refer to FIGS. 3 to 7 again. In the embodiment of the present application, the battery core assembly 2 includes an active material coating part 21 and a conductive part 22 . The active material coating part 21 is accommodated in the housing 11 . The part 21 is the part coated with active material in the battery cell assembly 2, which can assist in the deintercalation of metal ions during the charging and discharging process of the battery cell 10. The conductive part 22 is electrically connected to the active material coating part 21 and the pole. The metal structure is not coated with active material, and the pole is electrically connected to the active material coating part 21 through the conductive part 22 so that the charging and discharging operations of the battery cell 10 can be performed.

It should be noted that in the embodiment of the present application, the active material coating part 21 is divided into a positive active material coating part and a negative active material coating part. The positive active material coating part includes a positive current collector coated with positive active material. The part of the material layer, the negative active material coating part includes the part of the negative current collector coated with the negative active material layer. The conductive part 22 is divided into a positive conductive part and a negative conductive part. The positive conductive part is electrically connected to the positive active material coating part and the positive pole, and the negative conductive part is electrically connected to the negative active material coating part and the negative pole. It should be noted that the method of forming the first welding portion 71 is not limited. For example, it can be laser welding, friction welding, ultrasonic welding, and depending on factors such as the position, angle, or structure of the welding portion, vertical welding or oblique welding can be selected. As well as lap welding or edge welding, etc. For example, the first welding part 71 may be a long strip welding mark to improve welding reliability and increase over-current performance.

In some embodiments, the conductive part 22 and the pole body 1201 are welded together from the outside to form a first welding part 71 therebetween. The conductive portion 22 can be located inside the pole body 1201 , or can pass through a via hole on the pole body 1201 to overlap the outside of the pole body 1201 . When the conductive part 22 is located inside the pole body 1201, the first welding part 71 penetrates the pole body 1201 to connect with the conductive part 22; when the conductive part 22 overlaps the outside of the pole body 1201, the first welding part 71 It penetrates the conductive part 22 to connect with the pole body 1201 . The first welding part 71 is exposed on the outside of the pole body 1201, which may affect the reliability of the welding mark and subsequent connection with the bus components. Therefore, the first cover 13 is provided to cooperate with the pole body 1201 to cover the first welding part 71 .

In other embodiments, the conductive part 22 and the pole body 1201 are welded together from the inside to form a first welding part 71 therebetween. The conductive portion 22 can be located inside the pole body 1201 , or can pass through a via hole on the pole body 1201 to overlap the outside of the pole body 1201 . When the conductive part 22 is located inside the pole body 1201, the first welding part 71 penetrates the conductive part 22 to connect with the pole body 1201; when the conductive part 22 overlaps the outside of the pole body 1201, the first welding part 71 It penetrates the pole body 1201 to connect with the conductive part 22 . In order to ensure the reliability of welding, the first welding part 71 is provided through the pole body 1201 during welding to increase the welding strength. At this time, the first welding part 71 is exposed outside the pole body 1201, which may affect the reliability of the welding mark and subsequent connection with the bus components. Therefore, the first cover 13 is provided to cooperate with the pole body 1201 to cover the first welding part. Department 71.

In the above technical solution, the first welding part 71 is at least partially located on the side of the pole body 1201 away from the active material coating part 21. On the one hand, the metal residue generated during the welding process can be reduced from entering the battery cell 10 to a certain extent. This prevents metal residue from overlapping the positive and negative electrode plates, thereby reducing the possibility of internal short circuit in the battery cell 10 . On the other hand, the first welding part 71 can be kept away from the active material coating part 21. When the pole body 1201 and the conductive part 22 are welded at high temperature to form the first welding part 71, the first welding part 71 serves as a high-temperature heat source and can be kept away from the active material. The coating portion 21 can therefore reduce the impact of high temperature generated by welding on the active material coating portion 21 , reduce the probability of the active material coating portion 21 being damaged, and improve the reliability of the battery cell 10 . In addition, after the pole body 1201 is welded to the conductive part 22 inside the casing 11, when the battery cell 10 is welded to the bus part 30, the first cover 13 blocks the first welding part 71, which can play a protective role and weaken the pole. The high temperature generated when the pole body 1201 and the bus part 30 are welded affects the first welding part 71, thereby improving the connection reliability between the pole body 1201 and the conductive part 22.

For example, the high temperature generated when the pole body 1201 and the bus part 30 are welded has a certain probability of causing the first welding part 71 to melt again. At this time, due to the obstruction of the first cover 13, the high temperature generated when the pole body 1201 and the bus part 30 are welded. When the high temperature is transmitted to the first welding part 71, it is weakened, so that the first welding part 71 between the pole body 1201 and the conductive part 22 is not easily melted again, which can improve the reliability of the battery cell 10 during the manufacturing process. In some embodiments, with reference to Figures 8 and 9, the pole body 1201 has a first receiving groove 12110. The surface of the first pole 12 facing the active material coating part 21 is the pole inner end surface 122. The first receiving groove The slot of 12110 is formed on the inner end surface 122 of the pole, and the first receiving groove 12110 has a first end wall 12111 and a first side wall 12113. The first end wall 12111 is located away from the active material coating part of the first side wall 12113. 21, at least part of the conductive part 22 is accommodated in the first receiving groove 12110, the first welding part 71 is provided on the first end wall 12111, the first cover 13 cooperates with the pole body 1201, and covers the first welding Department 71.

For example, the first receiving groove 12110 is a groove body, and the groove body is a groove-shaped structure with a certain depth. For example, when the first pole 12 is disposed on the upper end wall of the housing 11 and the inner end surface 122 of the pole is the lower surface of the first pole 12, the first receiving groove 12110 is formed such that the groove is open downward and the groove wall is recessed upward. accommodating slot. For another example, when the first pole 12 is disposed on the lower end wall of the housing 11 and the inner end surface 122 of the pole is the upper surface of the first pole 12, the first receiving groove 12110 is formed such that the groove mouth is open upward and the groove wall is downward. Recessed receiving slot.

In the above technical solution, on the one hand, opening the first receiving groove 12110 on the first pole 12 can reduce the weight of the first pole 12 to a certain extent, so as to increase the weight energy density of the battery cell 10 and the battery 100; on the other hand, On the one hand, since the notch of the first receiving groove 12110 is formed on the inner end surface 122 of the pole, and the inner end surface 122 of the pole is the surface of the first pole 12 close to the active material coating part 21, the first The accommodating groove 12110 can be opened toward the direction of the active material coating part 21, thereby facilitating the conductive part 22 to extend into the first accommodating groove 12110, thereby improving assembly efficiency. Moreover, the first receiving groove 12110 in this form facilitates processing and improves production efficiency.

Moreover, the first receiving groove 12110 is easily processed to have a larger volume, so that more conductive parts 22 can be accommodated; at the same time, since the first receiving groove 12110 is open toward the direction of the active material coating part 21, the first receiving groove 12110 is 12110 can also be used as a buffer and temporary storage structure for the electrolyte, so that more electrolyte can be accommodated in the housing 11. Since the battery cell 10 will lose electrolyte during the charging and discharging process, when there is more electrolyte, the battery cell can be extended. The service life of the body 10; and also because the first accommodating groove 12110 is open toward the direction of the active material coating part 21, the first accommodating groove 12110 can also be used as an accommodating and buffering structure for the gas generated inside the battery cell assembly 2, reducing the number of battery cells. The expansion of the battery cell 10 improves the reliability and stability of the battery cell 10 .

In addition, since the first accommodating groove 12110 is located inside the first pole 12, it is difficult for external foreign matter and impurities to enter the first accommodating groove 12110, thereby reducing the impact of external foreign matter and impurities on the battery core assembly 2 and improving the working efficiency of the battery core assembly 2. Stability and reliability, thereby improving the stability and reliability of the battery cell 10 and the battery 100.

Secondly, by arranging the first welding part 71 between the pole body 1201 and the conductive part 22 on the first end wall 12111, on the one hand, the first welding part 71 can be further away from the active state when it is in the first receiving groove 12110. The substance coating part 21 further reduces the impact of the high temperature generated when the pole body 1201 and the conductive part 22 are welded to form the first welding part 71 on the active material coating part 21; on the other hand, the first containing groove 12110 not only has Accommodating at least part of the conductive part 22, the groove wall of the first receiving groove 12110 also has the function of electrically connecting with the conductive part 22, which can simplify the structure of the first pole 12 and facilitate the processing of the first pole 12, and The structure of the conductive part 22 can also be simplified, redundancy of the conductive part 22 can be reduced, and the cost of the conductive part 22 can be reduced. Moreover, by using the welding of the first end wall 12111 and the conductive part 22, the welding area formed by the first welding part 71 can be set relatively large, which not only reduces the difficulty of welding, but also improves the reliability and stability of the welding. Thus, the performance of the battery cell 10 is improved.

In addition, since the first welding part 71 is located in the first receiving groove 12110, it can not only prevent the first welding part 71 from protruding outside the first pole 12 and occupy the space outside the first pole 12, but also can make the second pole A welding part 71 is protected by the first cover 13 , thereby improving the welding reliability and stability of the conductive part 22 and the first pole 12 .

In addition, in the embodiment of the present application, the first end wall 12111 is configured as a closed structure without perforations, so as to isolate the first accommodation tank 12110 from the external space of the housing 11 and prevent the electrolyte in the housing 11 from leaking out. The problem of leakage of the first containing groove 12110.

8 and 9 , in some optional embodiments, the local shape of the conductive part 22 matches the local shape of the first end wall 12111, and is disposed snugly and electrically connected, so that the conductive part 22 and the first end wall 12111 are electrically connected. The first welding portion 71 between the end walls 12111 can extend along the length or width direction of the first end walls 12111. For example, when the first end wall 12111 is a plane, part of the conductive portion 22 can also be a plane and adhere to the first end wall 12111, and the adhered position is welded. As a result, the welding area can be increased and the reliability and stability of the welding can be improved.

It is worth noting that the shape of the first end wall 12111 is not limited, for example, it can be a flat plate shape, an arc plate shape, etc. Wherein, when the first end wall 12111 is a flat structure, the first end wall 12111 is arranged at an angle with the axial direction R of the first pole 12 , for example, it may be perpendicular to the axial direction R of the first pole 12 The flat plate structure may also be, for example, an inclined plate-like structure that is not perpendicular to the axial direction R of the first pole 12, but the inclination direction is not limited.

Of course, in other embodiments of the present application, the first welding portion 71 between the conductive portion 22 and the first end wall 12111 may not extend along the length or width direction of the first end wall 12111. For example, it may also be A plurality of discrete solder joints, for example, the conductive portion 22 has a plurality of spaced apart locations are respectively soldered to the first end wall 12111, which will not be described again here.

In some embodiments, with reference to FIG. 10 , the first end wall 12111 has a first sinking groove 12112 , and at least part of the first welding portion 71 is located in the first sinking groove 12112 . It can be understood that the sinking direction of the first sinking groove 12112 is a direction away from the active material coating part 21 . For example, at least part of the conductive part 22 can be disposed in the first sinking groove 12112 and connected with the first end. The wall 12111 is used to define the local connection of the first sink 12112.

In the above technical solution, on the one hand, the first sinking groove 12112 can be used to pre-position and limit the first welding part 71 , which not only helps to find the correct position for welding and improves production efficiency, but also helps to improve the stability of the conductive part 22 stability and reliability to ensure the stability and reliability of the charging and discharging process of the battery cell 10; on the other hand, by setting the first sinking groove 12112 on the first end wall 12111, part of the first end wall 12111 can be partially thinned The wall thickness is not only conducive to welding, but also conducive to reducing the weight of the first pole 12 and improving the weight energy density of the battery cell 10 .

In some optional embodiments, part of the conductive part 22 matches the shape of the first side wall 12113 and is arranged snugly. For example, when the first side wall 12113 is a curved surface, part of the conductive part 22 may also be a curved surface and fit snugly. Welding is performed on the first side wall 12113 so that the first welding portion 71 between the conductive portion 22 and the first side wall 12113 extends along the first side wall 12113 . As a result, the welding area can be increased, thereby improving the reliability and stability of welding.

Of course, the present application is not limited to this. In other embodiments of the present application, the first welding portion 71 between the conductive portion 22 and the first side wall 12113 may not extend along the first side wall 12113. For example, It may be a plurality of discretely arranged welding spots. For example, the conductive part 22 has a plurality of spaced-apart locations that are respectively welded to the first side wall 12113, which will not be described again here.

It should be noted that the number of the first side walls 12113 is not limited and can be determined according to the shape of the first receiving groove 12110, ensuring that one end of each first side wall 12113 away from the notch of the first receiving groove 12110 is connected to The first end wall 12111 is sufficient. For example, when the cross-sectional shape of the first receiving groove 12110 is circular or elliptical, the first end wall 12111 is circular or elliptical, and the number of the first side walls 12113 is one and is annular. Located on the circumferential edge of the first end wall 12111. For another example, when the cross-sectional shape of the first receiving groove 12110 is a rectangle or a racetrack shape, the first end wall 12111 is a rectangle or a racetrack shape, and the number of the first side walls 12113 is four, which are different from the first end wall. The four sides of 12111 are connected.

It should also be noted that the first receiving groove 12110 is not limited to the form defined by the first end wall 12111 and the first side wall 12113. For example, in some embodiments, the first end wall 12111 may not exist. In this case, each One end of the first side walls 12113 away from the slot opening of the first receiving groove 12110 converges together, so that the first receiving groove 12110 is defined only by the plurality of first side walls 12113. At this time, the conductive portion 22 can be electrically connected to The first side wall 12113 is sufficient to ensure the normal charging and discharging process of the battery cell 10 .

In addition, it is worth noting that in other embodiments of the present application, the first welding portion 71 between the conductive portion 22 and the first pole 12 may not be located in the first receiving groove 12110 . For example, the first welding portion 71 between the conductive portion 22 and the first pole 12 can also be located on the inner end surface 122 of the pole. In this case, part of the conductive portion 22 is accommodated in the first receiving groove 12110, which can also save money to a certain extent. space to increase the energy density of the battery cell 10 .

9 and 10 , in some embodiments, the first pole 12 has a first groove 126 , and the side surface of the first pole 12 away from the active material coating part 21 is the pole outer end surface 123 , and the first pole 12 has a first groove 126 . The notch of the groove 126 is formed on the outer end surface 123 of the pole, and the first cover plate 13 covers the notch of the first groove 126 .

It can be understood that the first groove 126 is a groove body, and the groove body is a groove-shaped structure with a certain depth. Moreover, when the first pole 12 is disposed on the upper end wall of the housing 11 and the outer end surface 123 of the pole is the upper surface of the first pole 12, the first groove 126 is formed such that the groove is open upward and the groove wall is recessed downward. (that is, a groove that is recessed toward the square that is close to the cell assembly 2). For another example, when the first pole 12 is disposed on the lower end wall of the housing 11 and the outer end surface 123 of the pole is the lower surface of the first pole 12, the first groove 126 is formed such that the groove opening is open downward and the groove wall is upward. The groove is concave (that is, concave toward the square shape close to the cell assembly 2).

In the above technical solution, on the one hand, since the first pole 12 is provided with the first groove 126, the weight of the first pole 12 can be further reduced, thereby improving the weight energy density of the battery cell 10 and the battery 100; on the other hand, On the one hand, the first groove 126 is located outside the first pole 12 , that is, open toward the side of the first pole 12 away from the interior of the housing 11 . The first groove 126 can be used to accommodate or install electrical connections in the battery 100 . The structural components of each battery cell 10 are used to fully utilize the space in the first pole 12 and improve the space utilization and volumetric energy density of the battery 100; by providing the first groove 126, the first cover 13 is sealed The notch of the first groove 126 facilitates welding of the first cover plate 13 and improves assembly efficiency.

In addition, since the first pole 12 has both the first receiving groove 12110 and the first groove 126, the first groove 126 is located on the side of the first receiving groove 12110 away from the active material coating part 21, and the first groove 126 is located on the side of the first receiving groove 12110 away from the active material coating part 21, and the first groove 126 is The groove 126 is open toward the direction away from the first receiving groove 12110 , thereby facilitating access to the first pole 12 from the outside of the first pole 12 , that is, the side of the first pole 12 away from the active material coating portion 21 through the first groove 126 . The conductive part 22 and the first end wall 12111 are laser welded to facilitate the electrical connection between the conductive part 22 and the first pole 12 through external welding. That is to say, through the above structural arrangement, the first pole 12 and the conductive part 22 can be easily welded externally through the first groove 126, which facilitates the processing and manufacturing of the battery cell 10, and can save processing and manufacturing costs.

Furthermore, in order to conveniently and effectively weld the conductive part 22 and the groove wall of the first accommodation groove 12110 through the first groove 126 and improve the welding reliability of the conductive part 22 and the groove wall of the first accommodation groove 12110, in this application In the embodiment, the part between the first groove 126 and the first receiving groove 12110 can be laser welded to the conductive part 22, that is, the spacer part 127 shown in Figure 10 and the conductive part 22 can be laser welded to achieve Electrical connection between the battery core assembly 2 and the first pole 12 . The thickness of the spacer 127 of the first pole 12 between the first groove 126 and the first receiving groove 12110 is relatively thin. The spacer 127 isolates the first groove 126 and the first receiving groove 12110. The distance of the spacer 127 is close to One side wall surface of the active material coating part 21 can serve as the first end wall 12111. When the conductive part 22 needs to be welded to the first end wall 12111, since the thickness of the spacer part 127 is relatively thin, it is advantageous to pass through the first recess. The groove 126 enables welding of the conductive part 22 and the first end wall 12111, thereby improving the convenience and reliability of welding.

In some embodiments, the first receiving groove 12110 can be configured in a cross-sectional shape with a length greater than a width, such as a rectangle, an ellipse, a track shape, etc., and the first welding portion formed by welding the conductive portion 22 to the first pole 12 71 may be a long strip welding mark parallel to the length direction of the first receiving groove 12110 to improve welding reliability and increase over-current performance. For example, when the conductive part 22 and the first end wall 12111 are welded to form the first welding part 71 as a long strip of welding mark, the width of the welding mark may be greater than or equal to 6 mm, and the distance between the welding mark and the first side wall 12113 may be Greater than or equal to 1mm, in order to ensure the overcurrent capability of the battery cell 10 while ensuring the convenience and reliability of welding.

9 , by arranging the first cover 13 that covers the first groove 126 , the first pole 12 can achieve indirect electrical connection with the bus component 30 through the first cover 13 . The position and structural arrangement of 13 make the electrical connection between the first cover 13 and the bus component 30 more convenient and the electrical connection area larger. Therefore, the electrical connection of adjacent battery cells 10 in the battery 100 can be facilitated by providing the first cover plate 13 , and since the electrical connection position between the battery cells 10 and the battery cells 10 is located at the first cover plate 13 , it is connected with the conductive The first welding portion 71 between the first portion 22 and the first pole 12 can be separated by the first groove 126, so there is less interference between the two, which can further improve the stability and reliability of the battery cell 10.

It should be noted that the specific structure of the battery core assembly 2 in the embodiment of the present application is not limited. For example, it may include, but is not limited to, the following two implementations.

In some embodiments, with reference to FIGS. 9-11 , the active material coating part 21 includes a current collector 211 and an active material layer 212 provided on the current collector 211 , and the conductive part 22 includes a tab part 221 that is electrically connected to the current collector 211 , the pole tab portion 221 includes a plurality of pole tabs 2211. The plurality of pole tabs 2211 converge near the current collector 211 (that is, gather in the direction of approaching each other) to form a first gathering portion 2212. The plurality of pole tabs 2211 are separated from each other. The positions of the current collector 211 are gathered and connected to form a second gathering part 2213. The first gathering part 2212 connects the second gathering part 2213 and the active material coating part 21. At least part of the second gathering part 2213 is accommodated in the first receiving groove 12110. , the second gathered portion 2213 is connected to the first end wall 12111 through the first welding portion 71 .

In the above technical solution, the plurality of pole tabs 2211 only converge (that is, gather in the direction of approaching each other) but are not connected when forming the first gathered portion 2212, while the plurality of pole tabs 2211 form the second gathered portion. At 2213, they not only come together but also connect into an integrated structure. For example, the plurality of pole tabs 2211 can be connected into an integrated plate structure by welding (such as ultrasonic welding) to form the second gathered portion 2213, but the application is not limited thereto. For example, it can also be bonded with conductive glue. , the plurality of pole tabs 2211 are gathered and connected to form the second gathering part 2213, which will not be described again here.

It should be noted that in the embodiment of the present application, the tab 2211 is divided into a positive tab 2211 and a negative tab 2211. The positive tabs 2211 that need to be gathered together are stacked together and processed. Ultrasonic pre-welding forms the second gathered portion 2213 of the positive electrode, which can reduce the inter-layer gap so that the fluffy tabs 2211 of the positive electrode form a plate structure with a certain stiffness. In the same way, the tabs 2211 of the negative electrode that need to be gathered together are stacked together and ultrasonic pre-welded to form the second gathered portion 2213 of the negative electrode, which can reduce the gap between layers and make multiple tabs 2211 of the negative electrode fluffy. Form a plate structure with a certain stiffness.

In the above technical solution, "the plurality of pole tabs 2211 converge at a position close to the current collector 211 to form a first gathered portion 2212, and a plurality of pole tabs 2211 converge at a position far away from the current collector 211 and are connected to form a second gathered portion 2213." Note: along the extension direction of the pole tab 2211, the first gathered portion 2212 and the second gathered portion 2213 are sequentially provided in the direction away from the current collector 211, and the first gathered portion 2212 and the second gathered portion 2213 are respectively The specific position is not limited, that is, it is not required to be how close the first gathered part 2212 is to the current collector 211, nor is it required to be how far the second gathered part 2213 is to the current collector 211. In some optional examples, the current collector 211 and the tab piece 2211 can be an integral piece. For example, for the positive electrode piece, they can be an integrally formed aluminum foil. For example, for the negative electrode piece, they can be an integrally formed copper piece. Foil etc.

In the above technical solution, since the pole tab portion 221 includes a second gathered portion 2213 formed by a plurality of pole tabs 2211 gathered and connected, at least part of the second gathered portion 2213 is accommodated in the first receiving groove 12110 to facilitate the conductive portion. The connection between 22 and the first pole 12 can fully utilize the space of the first pole 12 and improve the volumetric energy density of the battery cell 10 .

9-11, in the first embodiment, at least part of the second gathering portion 2213 is accommodated in the first receiving groove 12110, so that the space in the first pole 12 can be more fully utilized and further reduce the The space occupied by the tab portion 221 in the case 11 is to accommodate the larger-sized active material coating portion 21 , improve the volumetric energy density of the battery cell 10 , and can better reduce the space of the tab portion 221 in the case. The redundancy in the body 11 further reduces the probability of short circuit between the tab portion 221 and the active material coating portion 21 .

In this embodiment, the second gathered portion 2213 is connected to the first end wall 12111 through the first welding portion 71 . For example, with reference to FIG. 9 , when the second gathered portion 2213 and the first end wall 12111 are welded through the first welding portion 71 , such as when the second gathered portion 2213 is welded (eg, laser welded) to the first end wall 12111 , the electrical wiring can be simplified. The composition of the core component 2 reduces parts, simplifies the assembly process, and improves assembly efficiency. The first welding portion 71 between the second gathered portion 2213 and the first end wall 12111 can extend along the length direction or width direction of the first end wall 12111. Furthermore, the first end wall 12111 has a first sink. The first welding portion 71 between the groove 12112, the second gathering portion 2213 and the first end wall 12111 can also be located in the first sinking groove 12112, etc. The corresponding technical effects can be referred to the introduction of the above embodiments and will not be described again here.

10 , in some embodiments, the active material coating part 21 includes a current collector 211 and an active material layer 212 provided on the current collector 211 , the conductive part 22 includes a tab part 221 and an adapter piece 222 , the tab part 221 It includes a plurality of pole tabs 2211. The plurality of pole tabs 2211 converge at a position close to the current collector 211 to form a first gathered portion 2212. The plurality of pole tabs 2211 converge at a location far away from the current collector 211 and are connected to form a second gathered portion 2213. The first gathered part 2212 is connected to the second gathered part 2213 and the active material coating part 21. The adapter piece 222 is connected to the second gathered part 2213. At least part of the adapter piece 222 is accommodated in the first receiving groove 12110. The adapter piece 222 is connected to the first gathered part 2212. 222 is connected to the first end wall 12111 through the first welding portion 71 .

In the above technical solution, the active material coating part 21 can be electrically connected to the first pole 12 through the first gathering part 2212, the second gathering part 2213, and the adapter piece 222. The conductive part 22 is connected to the first pole. The electrical connection position of the pole 12 is located on the adapter piece 222. For example, the electrical connection can be achieved through welding (eg, laser welding) of the adapter piece 222 to the first pole 12. In addition, the adapter piece 222 and the tab piece 2211 are two separate components and are connected by welding (such as ultrasonic welding).

In the above technical solution, on the one hand, by housing at least part of the adapter piece 222 in the first receiving groove 12110 , the space in the first pole 12 can be more fully utilized, and the conductive portion 22 can be further reduced in the housing 11 occupy space within the battery cell 10 to increase the volumetric energy density of the battery cell 10 . On the other hand, by using the adapter piece 222 and the first welding portion 71 to realize the indirect electrical connection between the second gathered portion 2213 and the first pole 12 , the adapter piece 222 can utilize the portion avoiding the second gathered portion 2213 to connect with the first pole 12 . One pole 12 is welded, so that the adapter piece 222 and the first pole 12 are welded firmly, the risk of welding cracking is small, and the reliability and stability of the battery cell 10 can be further improved; at the same time, through the adapter piece 222 the electricity Connecting the first pole 12 and the tab 2211 can also simplify the structure of the tab 2211.

The connection method and position of the first welding portion 71 between the adapter piece 222 and the first pole 12 are not limited. For example, the first welding portion 71 between the adapter piece 222 and the first pole 12 can be located on the first end wall 12111 and/or the first side wall 12113. Further, the first welding portion 71 between the adapter piece 222 and the first end wall 12111 The first welding portion 71 between the two can extend along the length direction or width direction of the first end wall 12111. Furthermore, the first end wall 12111 has a first sinking groove 12112, between the adapter piece 222 and the first end wall 12111. The first welding part 71 between the two can be located in the first sinking groove 12112, etc. For the corresponding technical effects, please refer to the introduction of the above embodiments and will not be described again here. When the first welding portion 71 between the adapter piece 222 and the first pole 12 is located at the first end wall 12111 and/or the first side wall 12113, at least part of the adapter piece 222 is accommodated in the first receiving groove 12110. Therefore, the structure of the adapter sheet 222 can be simplified, redundancy can be reduced, and costs can be reduced.

9-11, in some embodiments, at least part of the first gathering portion 2212 is received in the first receiving groove 12110. In the above technical solution, at least part of the first gathered portion 2212 of the pole part 221 is accommodated in the first receiving groove 12110, so that the space in the first pole 12 can be more fully utilized, and the space of the pole part 221 can be further reduced. The occupied space in the casing 11 is used to accommodate the larger-sized active material coating part 21, improve the volumetric energy density of the battery cell 10, and better reduce the redundancy of the tab part 221 in the casing 11. In addition, the probability of short circuit between the tab part 221 and the active material coating part 21 is further reduced.

10 and 11 , in the second embodiment, the active material coating part 21 includes a current collector 211 and an active material layer 212 provided on the current collector 211 , and the conductive part 22 includes a tab part 221 and an adapter piece. 222. The pole tab portion 221 includes a plurality of pole tabs 2211 electrically connected to the current collector 211. The plurality of pole tabs 2211 are gathered close to the current collector 211 to form a first gathering portion 2212. The plurality of pole tabs 2211 are far away from the current collector. The positions 211 are gathered and connected to form the second gathered part 2213, and the adapter piece 222 is electrically connected to the second gathered part 2213. When the receiving portion 121 has the first receiving groove 12110, at least part of the adapter piece 222 can be received in the first receiving groove 12110 and be electrically connected to the first pole 12.

In the above technical solution, the second embodiment is compared with the solution including the adapter piece 222 in the first embodiment. In the second embodiment, at least part of the adapter piece 222 is accommodated in the first receiving groove 12110. , but the relative position of the pole lug portion 221 and the first receiving groove 12110 is not limited, that is, at least part of the pole lug portion 221 can be accommodated in the first receiving groove 12110, and the pole lug portion 221 can also be completely located outside the first receiving groove 12110. , thus meeting different structural design requirements.

In the above technical solution, by accommodating at least part of the adapter piece 222 in the first receiving groove 12110, the adapter piece 222 can occupy the space in the first pole 12, thereby reducing the space of the adapter piece 222 in the housing. 11 to accommodate the larger active material coating part 21, improve the volumetric energy density of the battery cell 10, and reduce the probability of short circuit between the adapter sheet 222 and the active material coating part 21, thus reducing the number of cells. The risk of short circuit of the component 2 can be improved to improve the stability and reliability of the battery cell 10 . In addition, accommodating at least part of the conductive part 22 in the accommodating part 121 is also conducive to stabilizing and limiting the conductive part 22 to improve the stability of the conductive part 22, thereby facilitating the welding of the conductive part 22 and the first pole 12 to improve the performance of the conductive part 22 and the first pole 12. Assembly efficiency.

In addition, by using the adapter piece 222 to realize the indirect electrical connection between the second gathered portion 2213 and the first pole 12, the adapter piece 222 can be welded to the first pole 12 using the portion avoiding the second gathered portion 2213, so that The welding between the adapter piece 222 and the first pole 12 is reliable, the risk of welding cracking is small, and the reliability and stability of the battery cell 10 can be further improved; at the same time, the first pole 12 and the pole are electrically connected through the adapter piece 222 The tab 2211 can also simplify the structure of the pole tab 2211.

For example, in some optional embodiments, such as the first embodiment above or the third embodiment below, when the second gathered part 2213 is directly electrically connected to the first pole 12, the conductive part 22 may only be composed of each The electrode assembly 2a is composed of a positive electrode tab and a negative electrode tab. For example, in other embodiments, such as the first embodiment or the second embodiment above, or the third embodiment or the fourth embodiment below, when the second gathering part 2213 and the first pole 12 rotate, When the tabs 222 are indirectly electrically connected, the conductive portion 22 may be composed of the positive tab and the negative tab in each electrode assembly 2a and each adapter piece 222.

In some embodiments, when the battery core assembly 2 includes two electrode assemblies 2a, the tabs 2211 of the two electrode assemblies 2a can be gathered together, and the folded position is located at the center between the two electrode assemblies 2a, so as to Form a symmetrically gathered form (for example, as shown in Figure 11 and Figure 12(a)). Or, in some other embodiments, when the tabs 2211 of the two electrode assemblies 2a are gathered together, the folded position can also be biased closer to one of the electrode assemblies 2a to form an asymmetric folded form (for example, Figure 12(b) ) and shown in Figure 12(c)). In addition, the electrode assembly 2a may be in the form of a full tab (for example, as shown in Figure 12(a)) or a half-outlet form (for example, as shown in Figures 11, 12(b), and 12(c)). .

Of course, the present application is not limited to this, and the pole tabs 2211 of the same polarity of the two electrode assemblies 2a may not be gathered together. For example, the tabs 2211 of each electrode assembly 2a are folded separately according to the positive and negative electrodes, that is, the positive tabs of one electrode assembly 2a are folded separately, and the positive tabs of the other electrode assembly 2a are also folded separately, which will not be described again here.

It should be noted that the accommodating part 121 in the embodiment of the present application is not limited to the form of the first accommodating groove 12110. For example, some other optional embodiments will be given below.

8, in some embodiments, the housing 11 has a mounting hole 113, and the first pole 12 is installed in the mounting hole 113; along the axial direction of the first pole 12, the depth H1 of the first receiving groove 12110 is greater than or equal to The minimum distance H2 from the inner end surface 122 of the pole to the mounting hole 113.

It should be noted that the specific shape of the first receiving groove 12110 is not limited, and may be a regular shape or an irregular shape, such as a cylindrical groove with a rectangular, elliptical, or racetrack-shaped cross-section, or a cylindrical groove with a cross-section. It can be a trapezoidal groove with a rectangular shape and a gradient cross-sectional size, a hemispherical groove with a circular cross-section and a gradual cross-sectional size, or a semi-ellipsoid groove with an elliptical cross-section and a gradual cross-sectional size, etc. Therefore, the depth H1 of the first receiving groove 12110 refers to the maximum depth of the first receiving groove 12110 along the axial direction R of the first pole 12 .

Since in the axial direction R of the first pole 12, the depth H1 of the first receiving groove 12110 is greater than or equal to the minimum distance H2 from the inner end surface 122 of the pole to the mounting hole 113, the volume of the first pole 12 can be fully utilized. The first receiving groove 12110 has a larger depth, which is conducive to accommodating more conductive parts 22, thereby reducing the space occupied by the conductive parts 22 in the housing 11 to a greater extent, and further improving the energy density of the battery cell 10. , further reducing the redundancy of the conductive part 22 in the housing 11; at the same time, because the first accommodation groove 12110 has a larger depth, it can also accommodate the gas produced by the battery assembly 2, ensuring the reliability and safety of the battery cell 10. stability, and can also accommodate more electrolyte to ensure the service life of the battery cell 10.

It should be noted that the volume of the first accommodating groove 12110 is not limited. For example, in some specific examples, the volume of the first accommodating groove 12110 that can be used to accommodate the conductive part 22 (denoted as the first volume V1) may be greater than or equal to 298 mm ³ . Therefore, the first receiving groove 12110 can have a relatively sufficient space to accommodate the conductive part 22 and facilitate the welding of the conductive part 22 and the first pole 12 . When the first volume V1 of the first accommodating groove 12110 is less than 298 mm ³ , the accommodating capacity of the first accommodating groove 12110 for the conductive part 22 is relatively weakened, and the welding difficulty of the conductive part 22 and the first pole 12 increases.

It is worth noting that the first volume V1 of the first accommodating groove 12110 is: the total volume V2 of the first accommodating groove 12110 and the volume that the first accommodating groove 12110 needs to accommodate other components except the conductive part 22 (denoted as the second The difference between volume V3), that is, V1=V2-V3. It can be understood that when the first receiving groove 12110 does not need to accommodate other components except the conductive part 22, the second volume V3 may be 0 mm ³ . For example, the first volume V1 of the first receiving groove 12110 may be 300mm ³ -1500mm ³ , for example, 300mm ³ , 400mm ³ , 500mm ³ , 600mm ³ , 700mm ³ , 800mm ³ , 1000mm ³ , 1200mm ³ , 1400mm ³ , 1500mm ³ etc.

Optionally, with reference to FIG. 8 , the first receiving groove 12110 can be provided corresponding to the position of the mounting hole 113 , or in other words, on the projection plane perpendicular to the axial direction R of the first pole 12 , the orthographic projection of the first receiving groove 12110 Located within the orthographic projection range of the mounting hole 113 , the first receiving groove 12110 can have a larger depth to accommodate more conductive parts 22 , thereby reducing the occupation of the conductive parts 22 in the housing 11 to a greater extent. space.

In some embodiments, with reference to FIG. 13 , the pole body 1201 has a second receiving groove 12120 . The surface of the pole body 1201 away from the active material coating part 21 is the pole outer end surface 123 . The notch of the second receiving groove 12120 Formed on the outer end surface 123 of the pole, the second receiving groove 12120 has a second end wall 12121 close to the active material coating part 21, the first welding part 71 is provided on the second end wall 12121, the first cover 13 and the pole The column body 1201 fits and covers the slot of the second receiving slot 12120.

It can be understood that the second receiving groove 12120 is a groove body, and the groove body is a groove-shaped structure with a certain depth. For example, when the first pole 12 is disposed on the upper end wall of the housing 11 and the pole outer end surface 123 is the upper surface of the first pole 12, the second receiving groove 12120 is formed such that the groove is open upward and the groove wall is recessed downward. accommodating slot. For another example, when the first pole 12 is disposed on the lower end wall of the housing 11 and the outer end surface 123 of the pole is the lower surface of the first pole 12, the second receiving groove 12120 is formed with the groove opening downward and the groove wall upward. Recessed receiving slot.

In the above technical solution, with reference to FIG. 13 , on the one hand, the first pole 12 is provided with the second receiving groove 12120 , which can reduce the weight of the first pole 12 to a certain extent, thereby increasing the weight energy of the battery cell 10 and the battery 100 . Density; on the other hand, since the notch of the second receiving groove 12120 is formed on the outer end surface 123 of the pole, and the outer end surface 123 of the pole is the surface of the first pole 12 on the side away from the active material coating part 21, so The second receiving groove 12120 can be opened in a direction away from the active material coating portion 21 , so that when at least part of the conductive portion 22 is received in the second receiving groove 12120 , the second receiving groove 12120 can be easily passed through. The slot enables the storage and arrangement of the conductive part 22, and the electrical connection operation between the conductive part 22 and the first pole 12 can be easily realized through the slot of the second accommodation slot 12120, thereby reducing the production of the battery cell 10. Difficulty, improve the production efficiency of the battery cell 10.

Among them, the first welding part 71 is provided on the second end wall 12121. That is to say, the second accommodation groove 12120 not only has the function of accommodating at least part of the conductive part 22, but the groove wall of the second accommodation groove 12120 also has the function of connecting with the conductive part 22. 22 realizes the function of welding, which can simplify the structure of the first pole 12 and facilitate the processing of the first pole 12 . Moreover, the opening direction of the second accommodating groove 12120 makes it easy to weld the conductive part 22 and the groove wall of the second accommodating groove 12120 through the slot of the second accommodating groove 12120, which can reduce the difficulty of welding and utilize The groove wall of the second accommodation groove 12120 is welded to the conductive part 22, which can make the welding area formed by the first welding part 71 between the conductive part 22 and the first pole 12 relatively large, improving the reliability of the electrical connection. and stability, thereby improving the performance of the battery cell 10 .

In addition, since the first welding part 71 between the conductive part 22 and the first pole 12 is located in the second receiving groove 12120, it is not only possible to prevent the first welding part 71 from protruding outside the first pole 12 and occupying the third pole. There is a space outside the pole 12 , and the position of the first welding part 71 can be protected by the first pole 12 , thereby improving the reliability and stability of the electrical connection between the conductive part 22 and the first pole 12 .

13 and 14 , in some embodiments, the local shape of the conductive part 22 matches the local shape of the second end wall 12121 , and is disposed and welded so that the conductive part 22 and the second end wall 12121 The first welding portion 71 can extend along the length or width direction of the second end wall 12121. For example, when the second end wall 12121 is a plane, part of the conductive portion 22 can also be a plane and adhere to the second end wall 12121, and the adhered position is welded. Thus, the area of the first welding portion 71 can be increased, and the reliability and stability of the welding can be improved.

It is worth noting that the shape of the second end wall 12121 is not limited, and may be, for example, a flat plate or an arc-shaped plate structure. Wherein, when the second end wall 12121 is a flat structure, the second end wall 12121 is arranged at an angle with the axial direction R of the first pole 12 , for example, it may be perpendicular to the axial direction R of the first pole 12 The flat-plate structure may also be an inclined flat-plate structure that is not perpendicular to the axial direction R of the first pole 12, but the direction of inclination is not limited.

In the above technical solution, since the conductive part 22 is connected to the pole body 1201 through the first welding part 71, there is welding slag at the first welding part 71, and the first welding part 71 is provided on the second end wall 12121. In this way, the welding slag can be kept away from the active material coating part 21 and the amount of welding slag entering the inside of the housing 11 can be reduced. On the other hand, the first cover plate 13 blocks the first welding part 71 and can protect the first welding part 71 In this way, the welding slag or part of the welding slag falling on the first welding part 71 can be blocked by the first cover 13, further reducing the amount of welding slag entering the inside of the housing 11, and reducing the welding slag entering the housing 11 twice. This method can greatly reduce the risk of short circuit caused by the presence of welding slag inside the battery cell 10 and improve the reliability of the battery cell 10 .

In addition, when the battery cell 10 transmits electricity to the outside, the pole body 1201 needs to be electrically connected to the bus part 30. At this time, the pole body 1201 and the bus part 30 are welded. In this case, the first cover 13 can block the second A welding part 71 also prevents the bus part 30 from contacting the first welding part 71 , or it can be understood that the bus part 30 and the first welding part 71 can be isolated from each other, which can also reduce the number of polar opposites in the first welding part 71 The influence of other welding positions on the column body 1201.

In some embodiments, referring to FIG. 55 , the conductive part 22 is located on the side of the second end wall 12121 facing the active material coating part 21 . In this case, the first welding part 71 is provided on the side of the second end wall 12121 facing the active material coating part 21 , and at this time, the first welding part 71 is between the surface of the pole body 1201 located outside the housing 11 The distance between them is relatively long, which can reduce the impact of high temperature on the first welding part 71 caused by the welding of the pole body 1201 and the bus component 30 .

13 , in some embodiments, the second receiving groove 12120 is connected to the interior of the housing 11 through the first through hole 12130 , and the conductive portion 22 is passed through the first through hole 12130 and is at least partially accommodated in the second receiving groove 12120 . The portion 22 is at least partially disposed on a side of the second end wall 12121 away from the active material coating portion 21 .

It can be understood that since the second accommodation groove 12120 can communicate with the interior of the housing 11 through the first through hole 12130, the second accommodation groove 12120 can also serve as a buffer and temporary storage structure for the electrolyte, so that the housing 11 can accommodate More electrolyte, because the electrolyte will be lost during the charging and discharging process of the battery cell 10, so when there is more electrolyte, the service life of the battery cell 10 can be extended; and also because the second accommodation groove 12120 can pass through the first perforation 12130 is connected to the inside of the casing 11, and the second receiving groove 12120 can also be used as a receiving and buffering structure for the gas produced inside the battery cell assembly 2, reducing the expansion of the battery cell 10 and improving the reliability and stability of the battery cell 10.

It is worth mentioning that when the receiving part 121 has the second receiving groove 12120 and the conductive part 22 is passed through the first through hole 12130 and is at least partially received in the second receiving groove 12120, the welding of the conductive part 22 and the first pole 12 No location limit.

For example, when the conductive part 22 penetrates the first through hole 12130 and is at least partially accommodated in the second receiving groove 12120, in some embodiments of the present application, the third conductive part 22 between the conductive part 22 and the first pole 12 A welding portion 71 is located on the hole wall of the first through hole 12130 formed by the first pole 12 .

In the above technical solution, by disposing the first welding part 7 between the conductive part 22 and the first pole 12 on the hole wall of the first through hole 12130, it is convenient to connect the conductive part 22 and the third pole through the second receiving groove 12120. One pole 12 is welded, and when the welding area between the conductive part 22 and the first pole 12 is large, the first through hole 12130 can be sealed by welding the conductive part 22 and the first pole 12 to save money. Sealing costs are reduced, electrolyte leakage is reduced, and sealing parts are saved.

Specifically, the conductive part 22 and the hole wall of the first through hole 12130 can be welded at the position where the first through hole 12130 is connected to the second receiving groove 12120, so as to facilitate the operation, and the welding mark can be controlled by controlling the welding mark. The printed and conductive portion 22 seals the first through hole 12130 to improve the problem of the electrolyte in the housing 11 leaking from the first through hole 12130 .

As another example, when the conductive part 22 is penetrated through the first through hole 12130 and is at least partially accommodated in the second receiving groove 12120, in other embodiments of the present application, there is a gap between the conductive part 22 and the first pole 12 The first welding portion 71 may also be located on the groove wall of the second receiving groove 12120 formed by the first pole 12 . This facilitates electrical connection operations. For example, when the conductive portion 22 is welded to the groove wall of the second receiving groove 12120 formed by the first pole 12 , it can prevent conductive particles generated by the welding from entering the housing 11 and causing short circuits and other problems. happened.

In some embodiments, with reference to Figures 13 and 14, the second containing groove 12120 also has a second side wall 12123, which is located on the side of the second end wall 12121 away from the active material coating part 21, and the second side wall 12123 is located on the side of the second end wall 12121 away from the active material coating part 21, and The two side walls 12123 and the second end wall 12121 form a second receiving groove 12120. The first through hole 12130 is opened in the second end wall 12121. The second end wall 12121 has a second sinking groove 12122. The first welding portion 71 Located at least partially within the second sink 12122.

In the above technical solution, on the one hand, since the first through hole 12130 is opened in the second end wall 12121, it is convenient for the conductive part 22 to extend into the second receiving groove 12120 through the first through hole 12130, which can simplify the structure of the conductive part 22 and reduce the number of conductive parts 22. The redundancy reduces the cost of the conductive part 22.

On the other hand, the part of the first welding part 71 located in the second sinking groove 12122 is set to match the shape of the second sinking groove 12122 and is closely arranged to achieve welding, so that the second sinking groove 12122 can be used to achieve alignment. The pre-positioning and position limiting of the first welding part 71 on the conductive part 22 is conducive to finding the correct position for welding, improving production efficiency, and improving the stability and reliability of the welding position to ensure the charging and discharging operation of the battery cell 10 Reliability and stability.

13 and 14 , the second end wall 12121 may have a flat plate structure, and the angle θ between the second end wall 12121 and the axial direction R of the first pole 12 is equal to 90°, that is, along the direction from the first through hole 12130 to The direction of the second side wall 12123, the second end wall 12121 and the active material coating part 21 are equidistant. This facilitates welding of the conductive part 22 and the second end wall 12121.

For another example, with reference to Figure 15, the angle θ between the second end wall 12121 and the axial direction R of the first pole 12 is greater than 90°, that is, along the direction from the first through hole 12130 to the second side wall 12123, the second end wall 12121 is The wall 12121 extends obliquely toward the direction approaching the active material coating portion 21 . Therefore, the extension distance of the conductive portion 22 along the second end wall 12121 can be increased to increase the reliability of the electrical connection. For example, the angle θ between the second end wall 12121 and the axial direction R of the first pole 12 may be 90°-145°, such as 100°, 110°, 120°, 130°, 140°, etc., so that On the one hand, the second end wall 12121 can be easily processed and electrically connected to the conductive part 22 , and on the other hand, the space in the first pole 12 can be fully utilized to accommodate the conductive part 22 .

For another example, with reference to FIG. 16 , the angle θ between the second end wall 12121 and the axial direction R of the first pole 12 is less than 90°, that is, along the direction from the first through hole 12130 to the second side wall 12123 , the second end wall 12121 has an angle θ of less than 90°. The wall 12121 extends obliquely in a direction away from the active material coating portion 21 . Therefore, the extension distance of the conductive portion 22 along the second end wall 12121 can be increased to increase the reliability of the electrical connection. For example, the angle θ between the second end wall 12121 and the axial direction R of the first pole 12 may be 45°-90°, such as 50°, 60°, 70°, 80°, etc., so that on the one hand, This makes the second end wall 12121 easy to process and weld with the conductive part 22. On the other hand, the space in the first pole 12 can be fully utilized to accommodate the conductive part 22.

Of course, the present application is not limited to this. In other embodiments of the present application, the first welding portion 71 between the conductive portion 22 and the second end wall 12121 may not extend along the length or width direction of the second end wall 12121. , it can also be a plurality of discretely arranged points. For example, the conductive part 22 has a plurality of positions arranged at intervals and are respectively welded to the second end wall 12121, which will not be described again here.

Please refer to Figure 14 again. Regardless of the specific value of the angle θ between the second end wall 12121 and the axial direction R of the first pole 12, in the embodiment of the present application, when the conductive part 22 and the second end wall 12121 are welded, , a second sinking groove 12122 can be provided on the second end wall 12121 according to requirements. The second sinking groove 12122 is a groove formed by partially sinking toward the end of the second end wall 12121 close to the active material coating part. The first welding portion 71 between the conductive portion 22 and the second end wall 12121 is at least partially located in the second sinking groove 12122 .

In the above technical solution, the part of the conductive part 22 located in the second sinking groove 12122 is set to match the shape of the second sinking groove 12122 and is arranged closely to achieve welding, so that the second sinking groove 12122 can be used to achieve alignment. The pre-positioning and limiting of the welding position of the conductive part 22 is conducive to finding the correct position for welding, improving production efficiency, and improving the stability and reliability of the electrical connection position to ensure the reliability and stability of the charging and discharging operation of the battery cell 10 sex.

It should be noted that in the embodiment of the present application, part of the conductive part 22 can also be configured to match and fit the shape of the second side wall 12123. For example, when the second side wall 12123 is a curved surface, the conductive part 22 The part may also be a curved surface and be attached to the second side wall 12123, and the attached position may be welded so that the first welding part 71 between the conductive part 22 and the second side wall 12123 is along the second side wall 12123. extend. Thus, the area of the first welding portion 71 can be increased, thereby improving the reliability and stability of welding.

It should also be noted that in other embodiments of the present application, the first welding portion 71 between the conductive portion 22 and the second side wall 12123 may not extend along the second side wall 12123. For example, it may also be discrete. The plurality of points provided, for example, the conductive portion 22 has a plurality of spaced apart locations are respectively welded to the second side wall 12123, which will not be described again here.

It can be understood that the number of the second side walls 12123 is not limited and can be determined according to the shape of the second receiving groove 12120. However, one end of each second side wall 12123 away from the notch of the second receiving groove 12120 is connected to Just go to the second end wall 12121. For example, when the cross-sectional shape of the second receiving groove 12120 is circular or elliptical, the second end wall 12121 is circular or elliptical, and the number of the second side walls 12123 is one and is annular. Located on the circumferential edge of the second end wall 12121. For another example, when the cross-sectional shape of the second receiving groove 12120 is rectangular or racetrack-shaped, the second end wall 12121 is rectangular or racetrack-shaped, and the number of the second side walls 12123 is four, respectively with the second end wall. The four sides of 12121 are connected.

It should also be noted that the second receiving groove 12120 is not limited to the form defined by the second end wall 12121 and the second side wall 12123. For example, in some embodiments, with reference to Figure 17, each second side wall 12123 One end of the slot away from the second receiving groove 12120 extends to the first through hole 12130, so that the second receiving groove 12120 is only defined by the plurality of second side walls 12123. At this time, the conductive portion 22 can be electrically connected to the second receiving groove 12120. Sidewall 12123.

In some embodiments, with reference to FIG. 29 , the active material coating part 21 includes a current collector 211 and an active material layer 212 provided on the current collector 211 . The conductive part 22 includes a tab part 221 that is electrically connected to the current collector 211 . The portion 221 includes a plurality of pole tabs 2211. The plurality of pole tabs 2211 converge at a position close to the current collector 211 to form a first gathering portion 2212. The plurality of pole tabs 2211 converge at a location far away from the current collector 211 and are connected to form a second gathering portion. 2213. The first gathered part 2212 connects the second gathered part 2213 and the active material coating part 21. At least part of the second gathered part 2213 is accommodated in the second receiving groove 12120. The second gathered part 2213 is connected with the first welded part 71 through the first welding part 71. The second end wall 12121 is connected.

In the above technical solution, since the pole tab portion 221 includes a second gathering portion 2213 formed by a plurality of pole tabs 2211 gathered and connected, at least part of the second gathering portion 2213 can be easily accommodated in the second receiving groove 12120 , to facilitate the assembly of the conductive part 22 and the first pole 12 . Secondly, at least part of the second gathered portion 2213 is accommodated in the second receiving groove 12120, which can utilize the space in the first pole 12, reduce the space occupied by the conductive portion 22 in the housing 11, and increase the volume energy of the battery cell 10. density.

In some optional examples, with reference to FIG. 29 , the position where the first gathered portion 2212 and the second gathered portion 2213 are connected can be set corresponding to the first through hole 12130 , that is, in the axial direction R perpendicular to the first pole 12 On the projection surface of 12130, and enter the second accommodation slot 12120 to reduce redundancy and cost.

Among them, it can be understood that the closing position of the pole tabs 2211 can be designed according to the position of the first through hole 12130, for example, using the symmetric closing form described above, or the asymmetric closing mode to achieve the first The connection position between the gathering part 2212 and the second gathering part 2213 is provided corresponding to the first through hole 12130, which will not be described again here. In addition, referring to the above, when the second gathered part 2213 is formed into a plate structure by ultrasonic pre-welding, it is convenient for the second gathered part 2213 to pass through the first through hole 12130.

In some embodiments, with reference to FIG. 30 , the active material coating part 21 includes a current collector 211 and an active material layer 212 provided on the current collector 211 . The conductive part 22 includes a tab part 221 and an adapter piece 222 . The tab part 221 Electrically connected to the current collector 211, the tab portion 221 includes a plurality of tabs 2211. The plurality of tabs 2211 converge near the current collector 211 to form a first gathering portion 2212. The plurality of tabs 2211 are far away from the current collector 211. The positions are gathered and connected to form a second gathered part 2213. The first gathered part 2212 connects the second gathered part 2213 and the active material coating part 21. The adapter piece 222 is connected to the second gathered part 2213. At least part of the adapter piece 222 accommodates In the second receiving groove 12120, the adapter piece 222 is connected to the second end wall 12121 through the first welding portion 71.

In the above technical solution, by accommodating at least part of the adapter piece 222 in the second receiving groove 12120, the adapter piece 222 can occupy the space in the first pole 12, thereby reducing the space of the adapter piece 222 in the housing. 11 to accommodate the larger active material coating part 21, improve the energy density of the battery cell 10, and reduce the probability of short circuit between the adapter sheet 222 and the active material coating part 21, thus reducing the number of cells. The risk of short circuit of the component 2 can be improved to improve the stability and reliability of the battery cell 10 .

In addition, by using the adapter piece 222 to realize the indirect electrical connection between the second gathered portion 2213 and the first pole 12, the adapter piece 222 can be welded to the first pole 12 using the portion avoiding the second gathered portion 2213, so that The welding between the adapter piece 222 and the first pole 12 is reliable, the risk of welding cracking is small, and the reliability and stability of the battery cell 10 can be further improved; at the same time, the first pole 12 and the pole are electrically connected through the adapter piece 222 The tab 2211 can also simplify the structure of the pole tab 2211.

In some embodiments, with reference to FIG. 30 , at least part of the first gathering portion 2212 is received in the second receiving groove 12120 .

In the above technical solution, by housing at least part of the first gathered portion 2212 and the adapter piece 222 in the second receiving groove 12120, the space in the first pole 12 can be more fully utilized, and the conductive portion 22 can be further reduced in size. The occupied space within the casing 11 is used to further increase the volumetric energy density of the battery cell 10 . Moreover, by providing the adapter piece 222 with a sheet structure, it is convenient for the adapter piece 222 to extend into the second receiving groove 12120 through the first through hole 12130.

29 , in some embodiments, the pole body 1201 is provided with a first receiving part 121 , the first receiving part 121 has a third receiving groove 12140 , and the surface of the first pole 12 facing the active material coating part 21 is On the inner end face 122 of the pole, the third receiving groove 12140 is located on the side of the second receiving groove 12120 close to the active material coating part 21, and the notch of the third receiving groove 12140 is formed on the inner end face 122 of the pole. The groove 12140 and the second receiving groove 12120 are connected through the first through hole 12130, and at least part of the first gathering portion 2212 is received in the third receiving groove 12140.

At this time, a part of the conductive part 22 is located in the third receiving groove 12140, and at the same time, the conductive part 22 is also penetrated through the first through hole 12130, and the remaining part of the conductive part 22 is located in the second receiving groove 12120, so that it can also be fully realized. The space in the first pole 12 is utilized to reduce the space occupied by the conductive part 22 in the housing 11 .

It is worth noting that when the conductive part 22 is connected to the second end wall 12121 or the second side wall 12123 by laser welding, with reference to FIG. 17 , there is a gap between the part of the conductive part 22 used for welding and the axis of the first through hole 12130 The angle β can be set to be greater than 5° to reduce the problem of laser entering the housing 11 through the first through hole 12130 and to facilitate the welding operation. In addition, when the angle β between the portion of the conductive portion 22 used for welding and the axis of the first through hole 12130 is close to 5°, edge welding can be used, and overlap welding can be used for the rest.

In some embodiments, with reference to FIGS. 27 and 28 , the housing assembly 1 further includes a second cover 14 . The second cover 14 covers the first through hole 12130 and the conductive portion 22 located in the second receiving groove 12120 .

It is worth noting that when the housing assembly 1 includes the second cover 14 , the housing assembly 1 may include the first cover 13 at the same time, or may not include the first cover 13 at the same time. Further, when the housing assembly 1 includes both the second cover plate 14 and the first cover plate 13, the first cover plate 13 can be in a composite form made of multiple materials, or in a non-composite form made of the same material.

In the above technical solution, at least part of the conductive part 22 is located in the second receiving groove 12120, and the second cover plate 14 covers this part of the conductive part 22. The second cover plate 14 also covers the first through hole 12130, so that when The electrolyte enters the second receiving groove 12120 from the first through hole 12130, and the problem of the electrolyte overflowing from the first pole 12 can be improved through the second cover plate 14, thereby improving the reliability of the battery cell 10.

For example, as shown in FIGS. 27 and 28 , when part of the conductive part 22 is sandwiched between the second cover 14 and the second end wall 12121 , laser welding can be used to weld part of the conductive part 22 and the second cover. The plate 14 and the second end wall 12121 are welded together to improve the reliability of the connection between the first pole 12 and the conductive part 22 . Moreover, since the second cover plate 14 can press the conductive portion 22, the second cover plate 14 can be used to improve the stability of the conductive portion 22 being accommodated in the second receiving groove 12120.

Please refer to Figure 13 again. In some embodiments, the housing 11 has a mounting hole 113. The first pole 12 is installed in the mounting hole 113. Along the axial direction of the first pole 12, the depth H3 of the second receiving groove 12120 is greater than Or equal to the minimum distance H4 from the outer end surface 123 of the pole to the mounting hole 113.

It should be noted that the specific shape of the second receiving groove 12120 is not limited, and may be a regular shape or an irregular shape, such as a cylindrical groove with a rectangular, elliptical, or racetrack-shaped cross section, or a cylindrical groove with a cross section. It can be a trapezoidal groove with a rectangular shape and a gradient cross-sectional size, a hemispherical groove with a circular cross-section and a gradual cross-sectional size, or a semi-ellipsoid groove with an elliptical cross-section and a gradual cross-sectional size, etc. It is worth noting that the racetrack shape described in this article refers to a shape in which the two short sides of the rectangle are replaced by convex curves, such as the shape shown in Figure 19(b).

Therefore, the depth H3 of the second receiving groove 12120 refers to the maximum depth of the second receiving groove 12120 along the axial direction R of the first pole 12 . Since in the axial direction R of the first pole 12, the depth H3 of the second receiving groove 12120 is greater than or equal to the minimum distance H4 from the outer end surface 123 of the pole 123 to the mounting hole 113, the volume of the first pole 12 can be fully utilized. The second receiving groove 12120 has a larger depth, which is conducive to accommodating more conductive parts 22, thereby reducing the space occupied by the conductive parts 22 in the housing 11 to a greater extent, and further improving the energy density of the battery cell 10. , further reducing the redundancy of the conductive part 22 in the housing 11; at the same time, because the second accommodation groove 12120 has a larger depth, it can also accommodate the gas produced by the battery assembly 2, ensuring the reliability and safety of the battery cell 10. stability, and can also accommodate more electrolyte to ensure the service life of the battery cells 10.

It should be noted that the volume of the second accommodating groove 12120 is not limited. For example, in some specific examples, the volume of the second accommodating groove 12120 that can be used to accommodate the conductive part 22 (denoted as the third volume V4) may be greater than or equal to 298 mm ³ . Therefore, the second receiving groove 12120 can have a relatively sufficient space to accommodate the conductive part 22 and facilitate the welding of the conductive part 22 and the first pole 12 . When the third volume V4 of the second accommodating groove 12120 is less than 298 mm ³ , the accommodating capacity of the second accommodating groove 12120 for the conductive part 22 is relatively weakened, and the welding difficulty of the conductive part 22 and the first pole 12 increases. For example, the third volume V4 of the second receiving groove 12120 may be 300mm ³ , 400mm ³ , 500mm ³ , 600mm ³ , 700mm ³ , 800mm ³ , 1000mm ³ and so on.

It is worth noting that the third volume V4 of the second accommodating groove 12120 is: the total volume V5 of the second accommodating groove 12120 and the second accommodating groove 12120 need to accommodate other components other than the conductive part 22 (such as the third component described herein). The difference between the volumes of the first cover plate 13 and the second cover plate 14 (denoted as the fourth volume V6) is V4=V5-V6. For example, in some specific examples, the total volume V5 of the second accommodation groove 12120 may be 1400 mm ³ -1500 mm ³ , so that the second accommodation groove 12120 may have more sufficient space to accommodate the conductive part 22 and other components. For example, the total volume V5 of the second receiving groove 12120 may be 1420mm ³ , 1440mm ³ , 1460mm ³ , 1480mm ³ , 1490mm ³ and so on.

Optionally, with reference to FIG. 13 , the second receiving groove 12120 can be provided corresponding to the position of the mounting hole 113 , or in other words, on the projection plane perpendicular to the axial direction R of the first pole 12 , the orthographic projection of the second receiving groove 12120 Located within the orthographic projection range of the mounting hole 113 , the second receiving groove 12120 can have a larger depth to accommodate more conductive parts 22 , thereby reducing the occupation of the conductive parts 22 in the housing 11 to a greater extent. space.

In the embodiment of the present application, the shape of the first through holes 12130, the number of the first through holes 12130, and the relative positional relationship between the first through holes 12130 and the second receiving groove 12120 are not limited.

For example, with regard to the shape of the first through hole 12130, with reference to FIGS. 18 and 19, in the embodiment of the present application, the shape of the first through hole 12130 may be a long strip shape to adapt to the sheet-like local shape of the conductive part 22. This configuration facilitates the sheet-like partial penetration of the conductive portion 22 . At the same time, when the first through hole 12130 is in the shape of a long strip, the second receiving groove 12120 can also be configured in a shape with a cross-sectional length greater than the width, such as a rectangle, an ellipse, a track shape, etc. In this case, the first through hole can be The length direction of 12130 is set to be consistent with the length direction of the cross section of the second receiving groove 12120, so that the space can be fully utilized. In addition, the solder mark formed by welding the conductive part 22 and the first pole 12 may be a long strip of solder mark parallel to the length direction of the first through hole 12130, so as to improve the welding reliability and increase the over-current performance. For example, when the conductive part 22 and the second end wall 12121 are welded to form a long strip of solder print, the width of the solder print may be greater than or equal to 6 mm, and the distance between the solder print and the second side wall 12123 may be greater than or equal to 1mm to ensure the overcurrent capability of the battery cell 10 while ensuring the convenience and reliability of welding.

Regarding the size and number of the first through holes 12130, in the embodiment of the present application, the size and specific position of the first through holes 12130 on the second receiving groove 12120 are not limited, and the relevant design can be carried out according to the number of the first through holes 12130. . For example, the width of the first through hole 12130 may be greater than or equal to 2 mm, which is beneficial for the conductive part 22 to pass through. For example, when there is only one first through hole 12130 opened in the second receiving groove 12120, in some examples, with reference to Figures 18 and 19, the first through hole 12130 can be centrally located relative to the second receiving groove 12120. In other examples, 20 , the first through hole 12130 may also be offset relative to the center of the second receiving groove 12120. For example, in some embodiments, with reference to Figure 20, the first through hole 12130 can be opened at the edge of the second end wall 12121 to be disposed close to the second side wall 12123, thereby increasing the available area of the second end wall 12121 to increase the The welding area of the conductive part 22 and the second end wall 12121.

It can be understood that after the conductive part 22 passes through the first through hole 12130, it will be folded in order to fit the second end wall 12121, but the direction of the folding is not limited. For example, when the first through hole 12130 is centrally arranged relative to the second receiving groove 12120, after the conductive part 22 passes through the first through hole 12130, it can be folded toward either side of the first through hole 12130 (in conjunction with FIG. 18), so that the conductive portion 22 can be appropriately reduced. The size of the second receiving groove 12120 enhances the structural compactness and structural strength; alternatively, after the conductive part 22 passes through the first through hole 12130, it can also be folded toward the opposite sides at the same time (see Figure 21) to reduce the welding area. The thickness reduces welding heat input, thereby reducing problems such as particle spatter.

For example, when there are multiple first through holes 12130 opened in the second receiving groove 12120, the length directions of the plurality of first through holes 12130 are arranged in parallel or substantially parallel to fully utilize the space. In this case, the folding direction of the conductive portion 22 after passing through the first through holes 12130 can be set according to the relative positional relationship of the plurality of first through holes 12130 . For example, when there are two first through holes 12130 opened in the second receiving groove 12120 and they are far away from each other (see FIG. 22 ), the two conductive parts 22 passing through the two first through holes 12130 can be folded in a direction closer to each other. ; And when there are two first through holes 12130 opened in the second receiving groove 12120 and are close to each other, the two conductive parts 22 passing through the two first through holes 12130 can be folded in a direction away from each other.

It can be understood that when there are multiple first through holes 12130 opened in the second receiving groove 12120, the number of the first poles 12 can be appropriately reduced, thereby reducing costs and processes.

In addition, in some embodiments, with reference to FIG. 20 and FIG. 21 , the first through hole 12130 can be centered relative to the active material coating part 21 , but the position of the first through hole 12130 relative to the second receiving groove 12120 is not limited, and it can be centered. It can be offset, because the first through hole 12130 is centrally arranged relative to the active material coating part 21 , so that the conductive part 22 can be gathered corresponding to the centerline position of the active material coating part 21 .

In some embodiments, referring to FIG. 21 , a seal 6 may be provided at the first through hole 12130 to improve the problem of the electrolyte in the housing 11 leaking from the first through hole 12130 . The material, shape and connection method of the sealing member 6 to the first through hole 12130 are not limited. For example, the sealing member 6 may be a metal piece made of the same material as the first pole 12 or the conductive part 22 , and may be made of the same material as the first pole 12 or the conductive part 22 . The wall surface at the first through hole 12130 of the first pole 12 is welded and matched to seal the first through hole 12130. For example, the sealing member 6 can be a plastic piece that is plug-fitted with the first through hole 12130 to seal the first through hole 12130. In the embodiment of the present application, the perforations 12130 can be designed according to actual requirements and are not limited.

Figure 23 is an exploded view of the structure of the battery cell 10 provided by some embodiments of the present application; Figure 24 is a partial cross-sectional schematic view of the case assembly 1 provided by some embodiments of the present application; Figure 25 is the case assembly shown in Figure 24 The structural exploded view of 1, combined with Figure 23 and Figure 24, in some embodiments of the present application, when the accommodation part 121 has the second accommodation groove 12120 of any of the above embodiments, optionally, the housing assembly 1 can also It further includes a first cover 13 , which cooperates with the first pole 12 and closes the opening of the second receiving slot 12120 . The first cover 13 is electrically connected to the first pole 12 .

In the above technical solution, by arranging the first cover plate 13 to close the opening of the second receiving tank 12120, the electrolyte in the housing 11 can be prevented from leaking from the opening of the second receiving tank 12120, and because the first cover plate 13 The opening of the second receiving slot 12120 is closed and electrically connected to the first pole 12, so that the first cover 13 can be used to easily realize the indirect electrical connection between the first pole 12 and the bus component, and it is beneficial to increase the size of the first pole 12. The connection area of the electrical connection is beneficial to reducing the resistance of the electrical connection.

It is worth noting that the matching manner and position of the first cover 13 and the first pole 12 are not limited, as long as the first cover 13 can seal the opening of the second receiving groove 12120 . For example, in some embodiments, referring to FIG. 22 , the first cover 13 can be welded to the first pole 12 . During processing, the conductive portion 22 can be first passed through the first through hole 12130 and welded to the second receiving groove 12120 . On the groove wall, the first cover plate 13 and the first pole 12 are then welded to close the slot of the second receiving groove 12120.

31 , in some embodiments, the pole body 1201 is provided with a first receiving portion 121 , the first receiving portion 121 has a fourth receiving groove 12150 , the fourth receiving groove 12150 is a groove body, and the groove body is a groove with a certain depth. Like structure, the surface of the pole body 1201 away from the active material coating part 21 is the pole outer end face 123. The notch of the fourth receiving groove 12150 is formed on the pole outer end face 123. The fourth receiving groove 12150 passes through the second The through hole 12160 is connected with the inside of the housing 11 , and the conductive part 22 may not be accommodated in the fourth receiving groove 12150 . For example, the conductive part 22 is provided in the second through hole 12160 , and the first welding part 71 is provided in the first receiving part 121 On the hole wall of the second through hole 12160 formed, the first cover plate 13 cooperates with the pole body 1201 and covers the second through hole 12160.

In the above embodiment, by providing the fourth receiving groove 12150, the welding of the conductive part 22 and the hole wall of the second through hole 12160 can be easily achieved. Moreover, in some cases, the second through hole 12160 can be sealed by welding the conductive part 22 and the first pole 12 . For example, the conductive part 22 and the hole wall of the second through hole 12160 can be welded at the position where the second through hole 12160 is connected to the fourth receiving groove 12150, so as to facilitate the operation, and the solder mark can be used by controlling the solder mark. The second through hole 12160 is sealed with the conductive portion 22 to improve the problem of the electrolyte in the housing 11 leaking from the second through hole 12160.

It should be noted that the specific shape of the fourth receiving groove 12150 is not limited, and may be a regular shape or an irregular shape, such as a rectangular, elliptical, or racetrack-shaped cross-section cylindrical groove, or a cross-section It can be a trapezoidal groove with a rectangular shape and a gradient cross-sectional size, a hemispherical groove with a circular cross-section and a gradual cross-sectional size, or a semi-ellipsoid groove with an elliptical cross-section and a gradual cross-sectional size, etc.

In the embodiment of the present application, the shape of the second through hole 12160 may be an elongated shape to adapt to the sheet-like partial shape of the conductive part 22, thereby facilitating the sheet-like partial penetration of the conductive part 22. At the same time, when the second through hole 12160 is in the shape of a long strip, the fourth receiving groove 12150 can also be configured in a shape with a cross-sectional length greater than the width, such as a rectangle, an ellipse, a track shape, etc. In this case, the second through hole can be The length direction of 12160 is set to be consistent with the length direction of the cross section of the fourth receiving groove 12150, so that the space can be fully utilized.

It should be noted that the first receiving part 121 in the embodiment of the present application is not limited to the above-mentioned form that must have at least one receiving groove. For example, in some other embodiments of the present application, with reference to FIG. 32 , the first receiving part 121 may only have a third through hole 12170 , and the surface of the first pole 12 facing the active material coating part 21 is the pole inner end surface 122 , the surface of the first pole 12 away from the active material coating part 21 is the pole outer end face 123, the third through hole 12170 is in the form of a through hole and penetrates the pole inner end face 122 and the pole outer end face 123, the conductive part 22 At least part of it is penetrated through the third through hole 12170. The electrical connection position between the conductive part 22 and the first pole 12 is not limited. For example, the electrical connection position may be located on the hole wall of the first pole 12 forming the third through hole 12170, or the conductive part 22 may also pass through the third through hole. 12170 so that the electrical connection position is located on the outer end surface 123 of the pole outside the third through hole 12170, and so on. In addition, the shape of the third through hole 12170 is not limited, and may be a regular-shaped hole with an equal cross-section, or a variable-section-shaped hole with an unequal cross-section, or the like. Moreover, the cross-sectional shape of the third through hole 12170 is not limited. For example, it can be a long shape, such as a rectangle, an ellipse, or a track shape, etc., so as to adapt to the sheet-like local shape of the conductive part 22, thereby benefiting the conductive part 22. The sheet is partially inserted through the third through hole 12170, which will not be described in detail here.

In the embodiment of the present application, the first pole 12 may be an integrally formed pole or a separately formed composite pole. 27 and 28 , in some embodiments, the pole body 1201 includes a first pole part 124 and a second pole part 125 that are made of different materials and are electrically connected. The second pole part 125 is located in the first pole part 124 On the side away from the active material coating part 21, the first receiving part 121 is provided on the first pole part 124 or the first pole part 124 and the second pole part 125, and the first welding part 71 is provided on the first pole part 124. A pole part 124.

In the above technical solution, the first pole 12 is provided in a composite form composed of different materials, and the first pole portion 124 located on the inside is accommodated, matched and electrically connected with the conductive portion 22 , and the third pole portion 124 located on the outside is used. The two-pole post part 125 is electrically connected to the bus part 30 and the like, thereby facilitating the assembly and electrical connection of the first pole post 12 and related components, reducing the number of welding positions between the first pole post 12 and the conductive part 22, and connecting the first pole post 12 to the conductive part 22. The mutual interference between the welding positions of the battery 12 and the bus component 30 of the battery 100 improves the reliability and stability of the battery cell 10 .

For example, when the material of the conductive part 22 is different from the material of the bus part 30 , the first pole part 124 can be made of the same material as the conductive part 22 , and the second pole part 125 can be made of the same material as the bus part 30 , thereby facilitating the welding of the second pole part 125 and the bus component 30 and the welding of the first pole part 124 and the conductive part 22, thereby improving the reliability and stability of the electrical connection between the conductive part 22 and the first pole 12. , as well as the reliability and stability of the electrical connection between the first pole 12 and the bus component 30 .

Further, when the first pole 12 is a composite form of the above embodiments and has the second receiving groove 12120 and the first through hole 12130 of any of the above embodiments, in some embodiments, the housing assembly 1 may also include For the second cover 14 of any of the above embodiments, at this time, the second cover 14 and the first pole part 124 may be made of the same material, and the first pole part 124 and the second cover 14 may be electrically connected. connection, thereby improving the reliability and stability of the electrical connection between the first pole portion 124 and the second cover 14 . For example, welding may be used to connect the first pole part 124 and the second cover plate 14 .

For example, with reference to Figures 27 and 28, when the first pole 12 is a negative pole, the first pole part 124 is made of copper, the second pole part 125 is made of aluminum, and the bus component 30 is an aluminum sheet, then , the second cover plate 14 can be made of copper, and the first cover plate 13 can be made of aluminum. At this time, the second cover plate 14 and the first pole portion 124 are made of the same material and can be effectively welded. The pillar portion 125 and the first cover plate 13 are made of the same material and can be welded effectively, and the first cover plate 13 and the bus part 30 are made of the same material and can be welded effectively.

In the embodiment of the present application, when the first accommodating part 121 has the second accommodating groove 12120, the cooperation between the battery core assembly 2 and the second accommodating groove 12120 is not limited depending on the composition of the battery core assembly 2. For example, it may include , but are not limited to the following third embodiment and fourth embodiment.

In some embodiments, with reference to FIG. 8 and FIG. 54 , the first cover 13 is provided with a second receiving portion 134 , the second receiving portion 134 has a fifth receiving groove 1341 , and the slot of the fifth receiving groove 1341 is formed on the first cover. An end surface of the plate 13 faces the active material coating part 12, and the fifth receiving groove 1341 has a third end wall 13411 and a third side wall 13412. The third end wall 13411 is located away from the active material coating part of the third side wall 13412. On one side of the covering portion 21 , at least part of the first welding portion 71 is received in the fifth receiving groove 1341 .

For example, when the outer end surface 123 of the first pole 12 does not form a receiving groove, the outer end surface 123 of the pole is flat. At this time, the first welding part 71 protrudes from the outer end face 123 of the pole, and the first cover plate 13. The fifth receiving groove 1341 is provided to accommodate the first welding part 71, so as to protect the first welding part 71 and subsequently connect it to the bus component.

Of course, the pole body 1201 has a second accommodating groove 12120. When the slot of the second accommodating groove 12120 is formed on the outer end face 123 of the pole, the first cover 13 can also be provided with a fifth accommodating groove 1341 and the second accommodating groove 12120. The first welding part 71 is cooperatively accommodated so as to protect the first welding part 71 and subsequently connect it to the bus component.

In the above technical solution, on the one hand, the first cover 13 is provided with the fifth receiving groove 1341, which can reduce the weight of the first pole 12 to a certain extent, thereby improving the weight energy density of the battery cell 10 and the battery 100; on the other hand, On the other hand, since the slot of the fifth receiving groove 1341 is formed on one end surface of the first cover plate 13 facing the active material coating part 12, and the third end wall 13411 is located on the third side wall 13412 away from the active material coating part 21, so that the fifth receiving groove 1341 can be opened in a direction away from the active material coating part 21, so that when at least part of the conductive part 22 is received in the fifth receiving groove 1341, it can be easily passed through The opening of the fifth receiving groove 1341 enables storage and arrangement of the first welding portion 71 , thereby reducing the production difficulty of the battery cells 10 and improving the production efficiency of the battery cells 10 .

In some embodiments, the first cover 13 is electrically connected to the pole body 1201; or, the first cover 13 is insulated from the pole body 1201. That is to say, the first cover 13 can be electrically connected to the pole body 1201. At this time, the first cover 13 can also participate in the bus component 30 for electrical connection, which can increase the area of the weldable area and facilitate the first pole 12 and Welding of the busbar 30. The first cover 13 may not be electrically connected to the pole body 1201 , that is, the two may be insulated. In this case, the first cover 13 mainly functions to protect the first welding part 71 .

In some embodiments, as shown in FIG. 26 , the first cover 13 includes a first conductive member 131 and a second conductive member 132 made of different materials. The first conductive member 131 cooperates with and is electrically connected to the pole body 1201 , and the second conductive member 132 is made of different materials. The component 132 cooperates with the first conductive component 131 and is electrically connected.

In the above technical solution, the first cover 13 is set in a composite form, and the first conductive member 131 is made of the same material as the first pole 12 , thereby facilitating the electrical connection between the first conductive member 131 and the first pole 12 . The connection, for example, can be easily done by welding to make the first conductive member 131 and the first pole 12 reliably and stably connected. Moreover, since the materials of the second conductive member 132 and the first conductive member 131 are different, it is convenient to use the second conductive member 132 to be electrically connected to a bus component whose material is different from the first pole 12. For example, the second conductive member 132 can be easily connected by welding. The conductive component 132 is reliably and stably connected to the bus component made of the same material as the second conductive component 132 .

For example, when the first pole 12 is a negative pole, the first pole 12 is a copper pole, and the bus component is an aluminum sheet, at this time, the first conductive member 131 can be made of copper, and the second conductive member can be 132 is made of aluminum. At this time, the first pole 12 and the first conductive member 131 are made of the same material and can be effectively welded, and the second conductive member 132 and the bus part are made of the same material and can be effectively welded, so that the third conductive member 132 can be effectively welded. One pole 12 is indirectly electrically connected to the bus component through the first cover 13 . Moreover, the first pole 12 and the first conductive member 131 are welded between copper materials, which have good fluidity and are not prone to cracks, which is beneficial to improving the sealing effect of the welding joint.

It is worth noting that the cooperation method between the first conductive member 131 and the second conductive member 132 is not limited. In some embodiments, with reference to Figures 24-26, the first conductive member 131 has a second groove 1311, the second conductive member 132 is embedded in the second groove 1311, and the notch of the second groove 1311 is formed on the second groove 1311. On the surface of a conductive member 131 on the side away from the active material coating part 21, so that the second conductive member 132 is exposed from the notch of the second groove 1311, or, in other embodiments, the first conductive member 131 and The connection method of the second conductive member 132 can also be fastening connection, snap connection, etc.

It should also be noted that the “exposed” in the second conductive member 132 is exposed from the notch of the second groove 1311 refers to: the first conductive member 131 is in contact with the second conductive member at the position of the notch of the second groove 1311. 132 is not blocked, and the second conductive member 132 is not required to protrude from the opening of the second groove 1311. For example, the second conductive member 132 can be flush with the first conductive member 131 and away from the second receiving groove 12120. The second conductive member 132 may protrude from the surface of the first conductive member 131 on the side away from the second receiving groove 12120 .

In the above technical solution, on the one hand, by embedding the second conductive member 132 in the first conductive member 131 , the assembly difficulty of the first conductive member 131 and the second conductive member 132 can be reduced, and the first conductive member 131 can be more easily assembled. The stability and convenience of cooperation with the second conductive member 132 can reduce the thickness of the first cover 13 and the space occupied by the first cover 13 to improve the space utilization of the battery cell 10 . On the other hand, since the second conductive member 132 can be exposed from the surface of the first conductive member 131 away from the second receiving groove 12120 through the opening of the second groove 1311, it is beneficial to realize the connection between the second conductive member 132 and The bus parts outside the first pole 12 are electrically connected.

In addition, since the notch of the second groove 1311 is formed on the surface of the first conductive member 131 on the side away from the second receiving groove 12120, it means that the second groove 1311 is open toward the direction away from the active material coating part 21, so that The portion of the first conductive member 131 used to define the groove wall of the second groove 1311 is located between the second receiving groove 12120 and the second conductive member 132 to separate the second receiving groove 12120 and the second conductive member. 132, thereby preventing the electrolyte entering the second groove 1311 from contacting the second conductive member 132, thereby reducing the leakage of the electrolyte.

Of course, in other embodiments, the first cover plate 13 may not be a composite form composed of multiple materials. For example, in other embodiments of the present application, with reference to FIG. 27 , the first cover plate 13 may also be configured as a whole. Non-composite forms made of the same material, for example, used to adapt to the positive pole, will not be described here.

Please refer to Figures 24-26 again. In some embodiments, the first cover 13 is also embedded in the notch of the second receiving groove 12120. In the above technical solution, by embedding the first cover plate 13 in the second receiving groove 12120, the assembly difficulty of the first cover plate 13 and the first pole 12 can be reduced, and the assembly difficulty between the first cover plate 13 and the first pole can be improved. The assembly stability of the pole 12, as well as the reliability and convenience of connection, can also reduce the space occupied by the first cover plate 13 outside the first pole 12. Moreover, since the first cover 13 is embedded in the slot of the second receiving groove 12120, there is relatively sufficient space in the second receiving groove 12120 to accommodate the conductive part 22.

Of course, in other embodiments of the present application, the cooperation method between the first cover 13 and the first pole 12 is not limited to being embedded in the second receiving groove 12120. The first cover 13 can also be directly covered in the first The outside of the pole 12 , that is, it is directly covered at the notch of the second receiving groove 12120 , so as to facilitate cooperation with the bus components of the battery 100 , which is not limited in this embodiment.

Please refer to Figures 24-26 again. Optionally, in the embodiment of the present application, at least part of the wall surface at the notch of the second accommodation groove 12120 formed by the first pole 12 is a guide slope 12126. The guide slope 12126 is used for To guide the first cover 13 to cooperate with the notch of the second receiving groove 12120. In the above technical solution, by processing the wall surface at the notch of the second accommodating groove 12120 into a slope with a guiding function, the assembly difficulty of the first cover plate 13 and the second accommodating groove 12120 can be reduced, and the first cover plate 13 can be improved. Assembly efficiency with the second receiving groove 12120. Moreover, when the first cover plate 13 is welded to the guide bevel 12126, the area of the welding point can be increased, the reliability of the welding connection between the first cover plate 13 and the first pole 12 can be improved, and the collapse of the molten pool or laser damage during welding can be improved. The problem of injection into the first pole 12.

Specifically, with reference to Figures 24-26, the second receiving groove 12120 includes a first groove section 12124 and a second groove section 12125 located on a side of the first groove section 12124 close to the pole outer end surface 123. The cross-sectional area of the second groove section 12125 is larger than the cross-sectional area of the first groove section 12124, so that the second receiving groove 12120 has a stepped groove shape, and the connection position between the first groove section 12124 and the second groove section 12125 forms a stepped surface. 12127, so that when the first cover 13 is embedded in the second receiving groove 12120, it can be embedded in the second groove section 12125 and supported on the step surface 12127.

In the above technical solution, by arranging the second receiving groove 12120 in the form of a stepped groove, the first cover plate 13 can be stably fitted at the notch position of the second receiving groove 12120, and the first cover plate 13 and the first pole can be improved. 12 connection stability, and the groove depth of the first groove section 12124 can be limited, so that there is relatively sufficient space in the second receiving groove 12120 to accommodate the conductive part 22.

Further, when the wall surface at the notch of the first pole 12 forming the second receiving groove 12120 is the guide slope 12126, the cross-sectional area of the second groove section 12125 can be set along the direction close to the outer end surface 123 of the pole. It is gradually enlarged so that the side wall of the second groove section 12125 is formed into a guide slope 12126, thereby facilitating processing and meeting the guide requirements simply and effectively.

Please refer to Figures 24-26 again. In some embodiments, the first cover plate 13 has a stress relief groove 133. The stress relief groove 133 is located in the peripheral area of the first cover plate 13 to assist the first cover plate 13 in stress relief. .

In the above technical solution, by arranging the stress relief groove 133 on the first cover plate 13, it is possible to release the stress generated during the processing of the first cover plate 13 or during the electrical connection between the first cover plate 13 and the first pole 12. stress, so as to improve related problems such as deformation or damage of the first cover plate 13 due to stress.

Specifically, when the first cover plate 13 and the second accommodation groove 12120 are embedded and welded, the stress relief groove 133 can be used to release the stress generated by the welding, improve the lateral conduction of heat, and reduce the probability of the first cover plate 13 being damaged or deformed. . At the same time, when the first cover 13 is in the composite form including the first conductive member 131 and the second conductive member 132 , the stress relief groove 133 can be provided on the first conductive member 131 and located on the outer periphery of the second conductive member 132 area, when the first conductive member 131 and the second receiving groove 12120 are embedded and welded, the stress relief groove 133 can be used to release the stress generated by the welding, improve lateral heat conduction, and reduce the probability of damage or deformation of the second conductive member 132. Moreover, when the second conductive member 132 and the first conductive member 131 are embedded and welded, the stress relief groove 133 can be used to release the stress generated by the welding, improve the lateral conduction of heat, and reduce the deformation of the first conductive member 131, which may cause the first conductive member to be deformed. The probability that 131 cannot be embedded in the second accommodation slot 12120.

27-28, in the embodiment of the present application, the housing assembly 1 can also be provided with a second cover 14 as required. The second cover 14 covers the first through hole 12130 and the second receiving groove 12120. outside the conductive part 22.

It is worth noting that when the housing assembly 1 includes the second cover 14 , the housing assembly 1 may include the first cover 13 at the same time, or may not include the first cover 13 at the same time. Further, when the housing assembly 1 includes both the second cover plate 14 and the first cover plate 13, the first cover plate 13 can be in a composite form made of multiple materials, or in a non-composite form made of the same material.

In the above technical solution, at least part of the conductive part 22 is located in the second receiving groove 12120, and the second cover plate 14 covers this part of the conductive part 22. The second cover plate 14 also covers the first through hole 12130, so that when The electrolyte enters the second receiving groove 12120 from the first through hole 12130, and the problem of the electrolyte overflowing from the first pole 12 can be improved through the second cover plate 14, thereby improving the reliability of the battery cell 10.

For example, as shown in FIGS. 27 and 28 , when part of the conductive part 22 is sandwiched between the second cover 14 and the second end wall 12121 , laser welding can be used to weld part of the conductive part 22 and the second cover. The plate 14 and the second end wall 12121 are welded together to improve the reliability of the connection between the first pole 12 and the conductive part 22 . Moreover, since the second cover plate 14 can press the conductive portion 22, the second cover plate 14 can be used to improve the stability of the conductive portion 22 being accommodated in the second receiving groove 12120.

33 to 35 , in some embodiments, the battery cell 10 further includes a bracket 3 , which is located in the housing 11 and on the side of the active material coating part 21 close to the first pole 12 . The bracket 3 There is an escape hole 31 for avoiding the conductive part 22. The conductive part 22 is adapted to extend through the escape hole 31 to the side of the bracket 3 away from the active material coating part 21, so as to be welded with the first pole 12, thereby ensuring that the battery The charging and discharging operation of the cell 10 proceeds normally.

In the above technical solution, by disposing the bracket 3 on the side of the active material coating part 21 close to the first pole 12 , the bracket 3 can be used to separate the active material coating part 21 from the case 11 , thereby improving the battery cell efficiency. The reliability of the body 10 and the escape hole 31 provided on the bracket 3 can guide and constrain the conductive part 22 to cooperate with the first pole 12 by passing through the escape hole 31, thereby eliminating the need for the conductive part 22 to bypass the edge of the bracket 3 By being close to the first pole 12, it can not only simplify the layout of the conductive part 22, save the material of the conductive part 22, and reduce the cost, but also support and guide the conductive part 22 to cooperate with the first pole 12 through the bracket 3, which can reduce the cost. The risk of short-circuit connection between the conductive part 22 and the active material coating part 21 is further improved to further improve the reliability of the battery cell 10 .

In some embodiments, the pole body 1201 is provided with a first receiving portion 121 , the bracket 3 is provided with a guide portion 32 , the guide portion 32 surrounds at least part of the escape hole 31 , and the guide portion 32 at least partially extends to the first receiving portion 121 .

It is worth noting that the guide portion 32 protrudes from the bracket 3 and extends into the first receiving portion 121 , and at least part of the escape hole 31 is formed in the guide portion 32 , so that when the conductive portion 22 is inserted through the escape hole 31 , the conductive portion At least part of 22 can be easily stored in the first receiving part 121, thereby improving the assembly efficiency of the conductive part 22; at the same time, through the arrangement of the guide part 32, the bracket 3 is The cooperation with the conductive portion 22 is closer and more reliable, making the structure of the battery cell 10 more compact, which is more conducive to improving the energy density of the battery cell 10 .

33 to 35 , optionally, the bracket 3 is provided with a third groove 38 , and at least part of the first pole 12 located in the housing 11 is accommodated in the third groove 38 .

In the above technical solution, by providing the third groove 38 on the bracket 3, at least part of the part of the first pole 12 located in the housing 11 is accommodated in the third groove 38 of the bracket 3, thereby improving the structure. The compactness not only helps to reduce the space occupied by the bracket 3 in the housing 11, but also helps to improve the stability and reliability of the first pole 12 to ensure that the first pole 12 is connected with the battery core assembly. 2. The reliability and stability of the electrical connection to improve the reliability and stability of the charging and discharging operation of the battery cell 10.

In addition, in some embodiments, the guide portion 32 can be used to participate in defining the third groove 38, thereby simplifying the structure of the bracket 3, reducing the design and processing difficulty of the bracket 3, and conducive to increasing the wall thickness of the guide portion 32, improving the Guidance reliability of the conductive part 32. Moreover, it is also conducive to improving the stability and reliability of the first pole 12 to ensure the reliability and stability of the electrical connection between the first pole 12 and the battery cell assembly 2, thereby improving the reliability of the charging and discharging operation of the battery cell 10. and stability.

33 to 35 , in some embodiments, the escape hole 31 includes a first hole section 311 and a second hole section 312 , and the second hole section 312 is located on the side of the first hole section 311 close to the active material coating part 21 , and the cross-sectional area of the second hole section 312 gradually increases along the direction away from the first hole section 311. The active material coating part 21 includes a current collector 211 and an active material layer 212 provided on the current collector 211. The conductive part 22 includes a tab portion 221 electrically connected to the current collector 211. The tab portion 221 includes a plurality of tabs 2211. The plurality of tabs 2211 converge near the current collector 211 to form a first gathering portion 2212. The pieces 2211 are gathered and connected away from the current collector 211 to form a second gathering part 2213. The first gathering part 2212 connects the second gathering part 2213 and the active material coating part 21. At least part of the first gathering part 2212 is accommodated in the second hole. In the section 312, the second gathering part 2213 is disposed through the first hole section 311.

In the above technical solution, by arranging the escape hole 31 to include the second hole section 312 that gradually expands toward the direction of the active material coating part 21, it is convenient for the second hole section 312 to accommodate more first gathering parts 2212, thereby improving the The compactness of the cooperation between the bracket 3 and the battery cell assembly 2 makes the overall volume of the battery cells 10 smaller, allowing the battery 100 to accommodate a larger number of battery cells 10 , thereby increasing the volumetric energy density of the battery 100 . In addition, in the above technical solution, the specific explanations of the first gathering part 2212 and the second gathering part 2213 have been explained in the previous embodiments and will not be described again here.

In some embodiments, the bracket 3 is an integrated structure; or, with reference to FIG. 36 , the bracket 3 is a split structure and includes a detachable first bracket 33 and a second bracket 34 . An escape hole 31 is defined between them.

In the above technical solution, the relief hole 31 is formed in the form of a through hole penetrating the bracket 3 . Therefore, the one-piece structure of the bracket 3 is easy to process, and the bracket 3 has good reliability. It is also convenient to assemble the bracket 3 and the housing assembly 1, thereby improving the assembly efficiency and coordination stability. It can be understood that how to process the bracket 3 can be specifically selected according to the material of the bracket 3 . For example, when the bracket 3 is an insulating plastic part, injection molding can be used to obtain the bracket 3 with an integrated structure.

Referring to Figure 37, when the bracket 3 has a split structure, the bracket 3 includes a detachable first bracket 33 and a second bracket 34. Both the first bracket 33 and the second bracket 34 are long plate-like structures. Detachable connection, for example, the two can be plugged or snap-fitted to facilitate assembly. At the same time, the side of the first bracket 33 close to the second bracket 34 has a half-hole structure. The second bracket 34 is also close to the first bracket 33 and has another half-hole structure corresponding to the shape. The half-hole structure of the first bracket 33 Together with the half-hole structure of the second bracket 34, they form an annular escape hole 31. That is, the escape hole 31 is defined between the first bracket 33 and the second bracket 34 .

In the above technical solution, the escape hole 31 is defined by the cooperation of the first bracket 33 and the second bracket 34. When the bracket 3 is assembled with the battery core assembly 2, there is no need to pass the conductive part 22 from one end of the escape hole 31 to the other end. , instead, the first bracket 33 and the second bracket 34 can be assembled at the position of the conductive part 22 to clamp the conductive part 22, so that the avoidance hole 31 surrounds the conductive part 22, thereby facilitating the assembly of the bracket 3 and the battery core assembly 2, and improving the assembly efficiency.

As an optional solution, when the cross-section of the escape hole 31 is elongated, the first bracket 33 and the second bracket 34 are located on both sides of the escape hole 31 in the width direction, for example, in the width direction of the escape hole 31 In the left-right direction, the first bracket 33 and the second bracket 34 are located on the left and right sides of the escape hole 31 , thereby facilitating the cooperation between the first bracket 33 , the second bracket 34 and the conductive part 22 .

33, 38 and 39, in the embodiment of the present application, the composition of the bracket 3 is not limited to this. For example, the edge of the bracket 3 can also be provided with a shell entry guide surface 35, and the shell entry guide surface 35 can be a slope or a curved surface. , and taking an orthographic projection along the axial direction R of the first pole 12 , the orthographic projection of the active material coating part 21 is all located within the orthographic projection range of the bracket 3 , and the orthographic projection range of the bracket 3 exceeds the orthographic projection range of the active material coating part 21 Orthographic projection range. During assembly, the bracket 3 and the battery core assembly 2 can be pre-assembled together, and then the pre-assembled assembly is installed into the housing 11. When installed, the bracket 3 is located at the front end of the active material coating part 21, that is, the bracket 3 is opposite to the active material coating part 21. The active material coating part 21 enters the housing 11 first, so that the shell entry guide surface 35 can be used to reduce the difficulty of the bracket 3 entering the housing 11, and the relatively large projected area of the bracket 3 can be used to protect the active material coating part 21. The probability of scratch damage between the active material coating part 21 and the housing 11 is reduced, and the assembly efficiency and success rate are improved. Moreover, the contact area between the bracket 3 and the active material coating part 21 can be increased, which can reduce the problem of stress concentration and eliminate other structural parts.

38 , in some embodiments of the present application, the battery cell 10 may further include an inner insulating member 4 , which is located in the housing 11 and wrapped around the active material coating part 21 , and the inner insulating member 4 Connect to bracket 3. In the above embodiment, on the one hand, by wrapping the inner insulating member 4 outside the active material coating part 21, the insulation reliability between the active material coating part 21 and the housing 11 can be improved, and the active material coating can be reduced or prevented. The contact between the part 21 and the casing 11 causes the casing 11 to be corroded, thereby reducing the electrolyte leakage problem caused by the corrosion of the casing 11, thereby improving the reliability of the battery cell 10; on the other hand, by arranging the internal The connection between the insulating member 4 and the bracket 3 can reduce the difficulty of fixing the inner insulating member 4 and improve the reliability of the inner insulating member 4 being wrapped outside the active material coating part 21 .

38 , in the embodiment of the present application, the bracket 3 includes a body part 36 and an extension part 37. The body part 36 is located on the side of the active material coating part 21 close to the first pole 12. The extension part 37 is connected to the body part 37. 36 is connected and located in the outer peripheral area of the active material coating part 21. For example, the extension part 37 can be connected to the circumferential edge of the main body part 36 to form an annular extension structure connected to the main body part 36, or it can be formed from the circumferential edge of the main body part 36. Partially extending in the circumferential direction to form a block-like structure that is convex relative to the body portion 36 . On the one hand, the arrangement of the extension portion 37 can limit the active material coating portion 21 to improve the problem of toner falling off from the edge of the active material coating portion 21 and causing corrosion when it overlaps with the housing 11 . On the other hand, through the provision of the extension portion 37, the inner insulating member 4 can also be fixed, thereby improving the connection reliability between the inner insulating member 4 and the bracket 3, and achieving a better insulation effect.

For example, with reference to FIG. 38 , the body part 36 and the extension part 37 may define a positioning groove 39 located on the side of the extension part 37 away from the active material coating part 21 , and the end of the inner insulating member 4 is embedded in the positioning groove. 39, to prevent the inner insulating member 4 from protruding from the edge of the body part 36, so that the body part 36 can be used to protect the inner insulating member 4 when it is put into the case, and the possibility of scratching and damaging the inner insulating member 4 and the shell 11 .

Specifically, with reference to FIG. 39 , the inner insulating member 4 can be an integrated film, with main body portions 41 located on both sides of the active material coating portion 21 in the thickness direction and a connecting portion 42 connecting the two main body portions 41 . The connecting portion 42 is located at The side edge of the active material coating part 21 away from the first pole 12 and the side edge of the main body part 41 away from the connecting part 42 extend to the extension part 37 and are connected to the extension part 37, thereby having better insulation performance, and Easy to connect.

In the embodiment of the present application, the specific manner of arranging the first pole 12 on the housing 11 is not limited. For example, it may be riveting or welding, which will be described separately below.

In some embodiments, with reference to Figures 56 and 57, the housing 11 has a first wall 110, the first wall 110 is formed with a mounting hole 113, and the pole body 1201 is disposed in the mounting hole 113, with the cross section of the mounting hole 113 located. is the projection plane. Along the direction perpendicular to the projection plane, the ratio of the projected area of the first welding portion 71 on the projection plane to the projected area of the first wall 110 on the projection plane is in the range of 0.1% to 1%.

The cross section of the mounting hole 113 is perpendicular to the axial direction (third direction Z) of the mounting hole 113 , and the projection direction in the above conditions is parallel to the axial direction of the mounting hole 113 , then the orthographic projection area of the first welding portion 71 can be understood is the orthogonal projected area of the connection area between the conductive part 22 and the pole body 1201 on the cross section of the mounting hole 113, then the orthogonal projected area of the first welding part 71 on the cross section of the mounting hole 113 can reflect the connection between the conductive part 22 and the pole. The area of the connection area between the pole bodies 1201, and the orthographic projection area of the first welding part 71 on the cross section of the mounting hole 113 satisfies the above conditions, the distance between the conductive part 22 and the pole body 1201 can be reduced to a certain extent. The equivalent resistance increases the over-current area of the first pole 12 and the over-current capability of the first pole 12, which is beneficial to increasing the charging speed of the battery cell 10 and improving the fast charging performance of the battery cell 10. At the same time To a certain extent, it is also beneficial to improve the heat diffusion capability of the first pole 12 .

In the above technical solution, by setting the ratio of the projected area of the first welding part 71 on the projection surface to the projected area of the first wall 110 on the projection surface to be in the range of 0.1% to 1%, the connection between the conductive part 22 and the pole is improved. The effective flow area between the column bodies 1201 increases the flow area of the first pole 12 and improves the flow capacity of the first pole 12, which is beneficial to increasing the charging speed of the battery cell 10 and at the same time to a certain extent. It is also conducive to improving the heat diffusion capacity of the first pole 12 and reducing the overcurrent temperature of the first pole 12, which is beneficial to reducing the risk of the battery cell 10 running out of control.

In some embodiments, with reference to Figure 57, the housing 11 has a mounting hole 113, and the pole body 1201 includes an integrally formed pole body part 12a, a first limiting platform part 12b and a second limiting platform part 12c. The main body part 12a is inserted through the mounting hole 113 of the housing 11. The first limiting platform part 12b and the second limiting platform part 12c are arranged along the axial direction of the mounting hole 113 with both ends of the pole main body part 12a. The limiting platform portion 12b is limited-fitting on the outside of the housing 11, and the second limiting platform portion 12c is limited-fitting on the inside of the housing 11, so that the pole body 1201 is riveted to the housing 11.

It can be seen that the first limiting platform portion 12b and the second limiting platform portion 12c respectively extend along the radial direction of the mounting hole 113 to the radial outside of the peripheral wall of the mounting hole 113. The first limiting platform portion 12b can limit the first pole. 12 moves relative to the housing 11 in the direction toward the inside of the housing 11, and the second limiting platform portion 12c can limit the movement of the first pole 12 relative to the housing 11 in the direction toward the outside of the housing 11, Therefore, the first pole 12 can be reliably installed at the mounting hole 113 through the first limiting platform portion 12b and the second limiting platform portion 12c, thereby achieving a fixed connection between the first pole 12 and the housing 11, which facilitates the first pole post 12. The assembly of the pole 12 and the casing 11, and the first pole 12 and the casing 11 do not need to use other connection methods, which can facilitate the reliable connection between the first pole 12 and the casing 11, which is conducive to simplifying the casing. The structure of the body assembly 1 is improved, and the assembly process of the housing assembly 1 is simplified.

Moreover, since the main body part 12a of the pole, the first limiting platform part 12b and the second limiting platform part 12c are integrally formed, parts can be saved, costs can be reduced, and the strength of the first pole 12 can be easily ensured, so that the third pole can be After the first pole 12 is matched with the case 11, it is not easy for the first pole 12 to be separated from the case 11 due to vibration or external pulling during the charging and discharging process of the battery cell 10, and it is also not easy to be cracked or damaged due to vibration or external pulling, and can The stability and reliability of the housing assembly 1 are improved, thereby improving the stability and reliability of the battery cells 10 .

Exemplarily, the axial direction of the mounting hole 113 is the third direction Z, the side wall of the housing 11 in the third direction Z is formed with a through mounting hole 113, the first limiting platform 12b and the second limiting platform. The portions 12c are provided at both ends of the pole main body 12a along the third direction Z.

It should be noted that in the above technical solution, the housing assembly 1 may have one or more poles, wherein at least one pole includes an integrally formed pole body part 12a, a first limiting platform part 12b and a third pole part. The first pole 12 of the pole main part 12a, the first limiting platform part 12b and the second limiting platform part 12c can also be a part of the pole on the housing 11 including the integrally formed pole main part 12a, The other part of the first pole 12 of the first limiting platform 12b and the second limiting platform 12c has other structures.

It can be understood that in this application, the first pole 12 can be used as a positive pole or a negative pole, and there is no limitation here.

For example, refer to Figure 57, which is a schematic diagram of the assembly process of the first pole 12 and the first wall 110 provided by some embodiments of the present application, the first limiting platform portion 12b, the second limiting platform portion 12c and the pole body. The first pole 12 is riveted to the housing 11 before the first pole 12 is riveted to the housing 11. One of the first limiting platform 12b and the second limiting platform 12c can extend along the axial direction of the mounting hole 113, and the other It can extend along the radial direction of the mounting hole 113. After the pole main body 12a is inserted into the mounting hole 113, tools or the like can be used to remove one of the first limiting platform portion 12b and the second limiting platform portion 12c. The pier is riveted to extend along the radial direction of the mounting hole 113 to achieve riveting fixation of the first pole 12 and the housing 11 .

In some embodiments, as shown in Figure 60, Figure 61 and Figure 65, in the axial direction, the thickness of the first limiting platform portion 12b is t1, 2mm≤t1≤3.2mm, so as to take into account the first pole at the same time 12 The riveting strength of the first limiting platform 12b and the volumetric energy density of the battery cell 10 avoid setting the thickness of the first limiting platform 12b larger due to the riveting strength of the first pole 12. , so that the volumetric energy density of the battery cell 10 is reduced, and at the same time, it is avoided that the thickness of the first limiting platform portion 12b is set smaller due to the volumetric energy density of the battery cell 10, so that the first pole 12 is at the first limit. The riveting strength at the base portion 12b is poor.

For example, t1 can be 2mm, 2.2mm, 2.5mm, 2.7mm, 2.9mm, 3mm, or 3.2mm, etc.

In some embodiments, as shown in Figures 60, 61 and 62, in the radial direction of the mounting hole 113, the width of the first limiting platform 12b is x1, x1≥1mm, so as to lift the first limiting platform 12b has a limiting effect on the first pole 12, thereby improving the riveting reliability of the first pole 12 and the housing 11 to a certain extent. The width d of the first limiting platform 12b can be understood as the distance from the outer peripheral wall of the pole main body 12a to the outer wall of the first limiting platform 12b along the radial direction of the mounting hole 113.

For example, x1 can be 1mm, 1.2mm, 1.5mm, 1.8mm, or 2mm, etc.

In some embodiments, as shown in Figures 60, 61 and 62, in the axial direction, the thickness of the second limiting platform portion 12c is t2, t2≤2mm, so as to ensure that the first pole 12 is in the first position at the same time. The riveting strength of the second limiting platform portion 12c and the volumetric energy density of the battery cell 10 avoid setting the thickness of the second limiting platform portion 12c to be larger due to the riveting strength of the first pole 12, making the battery The volumetric energy density of the cell 10 is reduced, and at the same time, it is avoided to consider the volumetric energy density of the battery cell 10 and set the thickness of the second limiting platform portion 12c to be smaller, so that the first pole 12 is at the second limiting platform portion. The rivet strength at 12c is poor.

For example, t2 can be 2mm, 1.8mm, 1.5mm, 1.4mm, or 1.2mm, etc.

In some embodiments, the distance between the end of the second limiting platform 12c away from the first limiting platform 12b and the inner wall of the housing 11 in the axial direction of the mounting hole 113 is less than or equal to 2 mm, so as to further lift the battery cell. The energy density of body 10.

In some embodiments, at least one of the first limiting platform portion 12b and the second limiting platform portion 12c is a separate piece from the pole main body 12a and is fixedly connected. That is to say, the first limiting platform portion 12b or the second limiting platform portion 12c can be separate parts from the pole main body 12a and fixedly connected, or the first limiting platform portion 12b and the second limiting platform portion can be 12c are separate parts from the pole main body 12a and are fixedly connected. In this technical solution, since at least one of the first limiting platform portion 12b and the second limiting platform portion 12c is a separate piece from the pole main body 12a, the first pole 12 and the housing 11 are assembled more easily. It is easy to operate, can reduce the difficulty of assembly, and is conducive to later disassembly and replacement, reducing usage costs.

In some embodiments, at least one of the first limiting platform portion 12b and the second limiting platform portion 12c is welded and connected to the pole main body portion 12a.

In some embodiments, the main body part 12a of the pole, the first limiting platform part 12b and the second limiting platform part 12c are integrated. It can be understood that in this way, the gap between the first pole post 12 and the housing 11 can be reduced. The assembly steps between the steps simplify the assembly process and improve work efficiency. At the same time, the main body part 12a of the pole, the first limiting platform part 12b and the second limiting platform part 12c are arranged into one piece, which can also make the first pole 12 and The installation between the housings 11 is more reliable, which can reduce the risk of the split pole posts falling off between the first pole post 12 and the housing 11 due to loose components.

Secondly, the pole main body part 12a, the first limiting platform part 12b and the second limiting platform part 12c can be made of the same or different materials; of course, the pole main body part 12a, the first limiting platform part 12b and the second limiting platform part 12c can be made of the same or different materials. The table portion 12c can also be a separate piece.

In some embodiments, as shown in FIGS. 60 , 61 and 62 , the battery 100 further includes an insulating sealing component 8 disposed between the first pole 12 and the housing 11 to realize the first pole. Insulation and sealing between column 12 and housing 11.

In some embodiments, as shown in Figures 60, 61 and 62, the insulating sealing component 8 includes an insulating member 81 and a sealing member 82, and the insulating member 81 is provided between the first limiting platform 12b and the housing 11; The sealing member 82 is provided between the second limiting platform part 12c and the housing 11. A part of the insulating part 81 and/or a part of the sealing part is fitted between the pole body part 12a and the peripheral wall of the mounting hole 113. The insulating part 81 It can play an insulating role between the first limiting platform portion 12b and the housing 11 to ensure the reliability of the insulation, and the sealing member 82 can play a sealing role to prevent the electrolyte in the housing 11 from overflowing easily.

In some embodiments, as shown in Figures 60, 61 and 62, a matching groove is formed on the outer wall of the housing 11 to accommodate the insulating member 81, which facilitates the positioning and installation of the insulating member 8, to a certain extent. This can prevent the insulating member 8 from being easily misaligned during the riveting process of the first pole 12 and the housing 11. At the same time, on the premise that the housing 11 is reliable in use, by setting the matching groove, it is helpful to reduce the protrusion of the insulating member 8. The height of the first pole 12 from the outer wall of the housing 11 is beneficial to reducing the height of the first pole 12 protruding from the outer wall of the housing 11 , so as to increase the volumetric energy density (VED) of the battery cell 10 . Of course, the outer side wall of the housing 11 may not be formed with a matching groove.

In some embodiments, as shown in FIGS. 60 , 61 and 62 , the inner wall of the housing 11 is formed with a mating protrusion, and the mating protrusion stops against the seal 82 to help improve the sealing reliability of the seal 82 . Of course, the inner side wall of the housing 11 may not be formed with matching protrusions.

For example, in the examples shown in Figures 60, 61 and 62, the outer side wall of the housing 11 is formed with a mating groove to accommodate the insulating member 8, and the inner side wall of the housing 11 is formed with mating protrusions. against seal 82.

Alternatively, the insulating and sealing component 8 may be an integral part, that is, the insulating component 8 and the sealing component 82 may be an integral component. In this case, the materials of the insulating component 8 and the sealing component 82 may be the same or different; of course, the insulating component 8 and the sealing component 82 Also available as separate parts.

Specifically, with reference to Figures 40-42, before riveting, the first pole 12 may include a stopper 1281 and a penetration part 1282. During assembly, the stopper 1281 is stopped inside the housing 11 and the penetration part is The part 1282 is passed through the mounting hole 113, and then the part of the through part 1282 located outside the housing 11 is riveted to form a flange part 1283. The flange part 1283 is stopped outside the housing 11, thereby achieving the first pole. Installation of column 12. It should be noted that the penetration part 1282 may refer to the main body part 12a of the pole below, the stopper part 1281 may refer to the second limiting platform part 12c below, and the flange part 1283 may refer to the first limiting part 12c below. Desk 12b.

Optionally, with reference to Figures 40 and 41, the housing assembly 1 may include several sealing gaskets fitted between the housing 11 and the first pole 12, such as the first sealing gasket 191 and the second sealing gasket shown in Figure 40. The sealing gasket 192 and so on, the sealing gasket is assembled in place before riveting. After the first pole 12 is riveted, the first pole 12 presses the sealing gasket to form a seal, so that the sealing gasket can be used to improve the cooperation between the first pole 12 and the housing 11 The sealing property. Among them, the number, position and material of the sealing pads are not limited. For example, the material can be silicone, plastic, etc., and there are no restrictions here.

Optionally, with reference to FIG. 41 , the length c of the flange portion 1283 may be greater than or equal to 1 mm, and the thickness d may be greater than or equal to 2 mm to improve the riveting strength of the first pole 12 . When the length c of the flange portion 1283 is less than 1 mm and/or the thickness d is less than 2 mm, the reliability of the first pole 12 and the housing 11 is reduced under relatively strong vibration.

For another example, in other embodiments of the present application, with reference to FIGS. 6 and 7 , the first pole 12 may have a split structure and be connected by welding to be installed on the housing 11 . For example, the first pole 12 includes a first part 1291 and a second part 1292. At least part of the first part 1291 is blocked outside the housing 11, and at least part of the second part 1292 is blocked inside the housing 11. The first part 1291 At least one of the second portion 1292 is passed through the mounting hole 113 and connected with another welding (such as laser welding), so that the first pole 12 can be installed.

In some optional embodiments, with reference to FIG. 45 and FIG. 46 , there are multiple first poles 12 and they are all located on the same side surface of the housing 11 , thereby facilitating installation and improving assembly efficiency.

It should be noted that the arrangement of the plurality of first poles 12 on the same side surface is not limited. For example, when the cross section of the first pole 12 is an elongated structure, for example, the cross section length is greater than or equal to three times. The cross-sectional width, such as ellipse, track shape or rectangle, etc., has good adaptability to the thin and flat shape of the housing 11. For example, the plurality of first poles 12 are disposed on one side surface (denoted as the first wall 110 ) of the housing 11 in the height direction, and the length direction of each first pole 12 is aligned with the first wall of the housing 11 . The length directions of the first poles 110 are consistent, and the plurality of first poles 12 are spaced apart along the length direction and/or width direction of the first wall surface 110 .

For example, in the example shown in FIG. 45 , when the first wall 110 has two first poles 12 , the two first poles 12 are spaced apart along the length direction of the first wall 110 . Optionally, with reference to Figure 45, the part of the first pole 12 located outside the housing 11 (denoted as the pole exterior) is annular. In the length direction of the first wall 110, the inner ring length a1 of the pole exterior is greater than or It is equal to 1/3 of the length a0 of the first wall surface 110. In the width direction of the first wall surface 110, the width b1 of the inner ring outside the pole is greater than or equal to 3/4 of the width b0 of the first wall surface 110. This is beneficial to providing a larger area for the first pole 12 to be electrically connected to the bus component, so as to further improve the current carrying capacity of the first pole 12 . For example, the length a1 of the inner ring outside the pole is greater than or equal to 50 mm, and the width b1 of the inner ring outside the pole is greater than or equal to 30 mm.

In addition, with reference to Figure 45, when the first wall 110 has two first poles 12, and the two first poles 12 are spaced apart along the length direction of the first wall 110, in some optional embodiments, the first poles 12 are The pole 12 includes a portion located inside the housing 11 (referred to as the inside of the pole) in the length direction of the first wall 110. The length of the inside of the pole is greater than or equal to 1/3 of the length of the first wall 110. In the first In the width direction of the wall 110 , the width inside the pole is greater than or equal to 3/4 of the width of the first wall 110 . Therefore, it is beneficial for the first pole 12 to provide a larger area for electrical connection with the conductive portion 22 , so as to further improve the overcurrent capability of the first pole 12 . For example, the length inside the pole is greater than or equal to 50 mm, and the width inside the pole is greater than or equal to 30 mm.

For another example, in the example shown in FIG. 46 , when the first wall 110 has four first poles 12 , two of the first poles 12 are spaced apart along the width direction of the first wall 110 to form a group, a total of two The groups are spaced apart along the length of the first wall 110 . Optionally, with reference to Figure 46, the part of the first pole 12 located outside the housing 11 (denoted as the pole exterior) is annular. In the length direction of the first wall 110, the inner ring length a2 of the pole exterior is greater than or It is equal to 1/3 of the length a0 of the first wall surface 110. In the width direction of the first wall surface 110, the width b2 of the inner ring outside the pole is greater than or equal to 1/5 of the width b0 of the first wall surface 110. This is beneficial to providing a larger area for the first pole 12 to be electrically connected to the bus component, so as to further improve the current carrying capacity of the first pole 12 . For example, the length a2 of the inner ring outside the pole is greater than or equal to 50 mm, and the width b2 of the inner ring outside the pole is greater than or equal to 8 mm.

In addition, with reference to FIG. 46 , when the first wall 110 has four first poles 12 , two of which are spaced apart along the width direction of the first wall 110 to form a group, a total of two groups along the first wall 110 When spaced in the length direction of It is greater than or equal to 1/3 of the length of the first wall 110 . In the width direction of the first wall 110 , the width of the inside of the pole is greater than or equal to 1/5 of the width of the first wall 110 . Therefore, it is beneficial for the first pole 12 to provide a larger area for electrical connection with the conductive portion 22 , so as to further improve the overcurrent capability of the first pole 12 . For example, the length inside the pole is greater than or equal to 50 mm, and the width inside the pole is greater than or equal to 8 mm.

In some embodiments, with reference to FIG. 45 and FIG. 46 , part of the first pole 12 is located inside the housing 11 , part of the first pole 12 is located outside the housing 11 , and part of the first pole 12 is located outside the housing 11 . The orthographic projection area of the portion on the first wall 110 is greater than or equal to 5% of the area of the first wall 110 . For example, the orthographic projection area of the portion of the first pole 12 located outside the housing 11 on the first wall 110 is greater than or equal to 5% of the area of the first wall 110 . It is equal to 5%, 6%, 7%, 8%, 9%, 10%, etc. of the area of the first wall 110 . This is beneficial to increasing the connection area between the first pole 12 and the bus component, increasing the effective flow area between the first pole 12 and the bus component, and is beneficial to increasing the charging speed of the battery cell 10 .

In addition, in some embodiments, with reference to FIG. 47 , the vertical height t1 of the portion of the first pole 12 protruding from the outer surface of the first wall 110 (denoted as the outside of the pole) from the first wall 110 may be less than or equal to 3.2 mm, the vertical height t2 of the part of the first pole 12 protruding from the inner surface of the first wall 110 (denoted as the inside of the pole) from the first wall 110 may be less than or equal to 2 mm, so as to increase the volume of the battery cell 10 Energy Density.

Figure 48 is a schematic cross-sectional view of the housing assembly 1 provided by some embodiments of the present application; Figure 49 is a schematic cross-sectional view of the housing assembly 1 provided by some embodiments of the present application; Figure 50 is a battery cell provided by some embodiments of the present application. Figure 51 is a cross-sectional view along line E-E in Figure 50; Figure 52 is a partial cross-sectional view of the battery cell 10 provided in some embodiments of the present application. Please refer to Figures 48 to 52. In the embodiment of the present application, the housing 11 specifically includes a housing 111 and a housing cover 112. The housing 111 is a square annular structure with one or both ends open. When one end is open, , the number of the shell cover 112 is one, and the cover is located in the open position. When both ends of the shell cover 112 are open, the number of the shell cover 112 is two, and they are respectively covered at the two open ends of the shell body 111 .

In detail, when the shell 11 includes a shell body 111 and a shell cover 112, and one end of the shell body 111 is open, the shell body 111 is an integrally molded part, specifically a square structure formed by stretching. At this time, the first pole can be 12 is provided on at least one of the shell body 111 or the shell cover 112 . For example, with reference to FIG. 48 , the first pole 12 may be disposed at an end of the housing body 111 away from the housing cover 112 . When the battery cell 10 is used in a vibration environment, the amplitude of the connection between the shell body 111 and the shell cover 112 is small, and the connection position between the shell body 111 and the shell cover 112 is not easy to crack, which can improve the reliability of the battery cell 10 and can It is beneficial to reduce the wall thickness of the housing 111 , thereby reducing cost and weight, and is beneficial to miniaturization of the battery cell 10 .

As an optional solution, please refer to FIG. 48 again. When the number of the first poles 12 is multiple, all the first poles 12 are provided at one end of the housing 111 away from the housing cover 112 . Therefore, when the battery cell 10 is used in a vibrating environment, the amplitude of the connection between the shell body 111 and the shell cover 112 is smaller, and the connection position between the shell body 111 and the shell cover 112 is less likely to crack, which can improve the reliability of the battery cell 10 . In addition, the wall thickness e1 of the end wall of the shell body 111 away from the shell cover 112 can be reduced to less than or equal to 2 mm, and the wall thickness e2 of the side wall of the shell body 111 connecting the end wall and the shell cover 112 can be reduced. Thinning to less than or equal to 0.8 mm can reduce cost and weight, and facilitate miniaturization of the battery cell 10 .

When the first receiving groove 12110 corresponding to the mounting hole 113 is formed on the first pole 12 , the wall thickness of the portion of the first pole 12 located on the side of the first receiving groove 12110 away from the active material coating part 21 is Thin, so that the conductive part 22 and the first pole 12 can be welded from the outside of the shell 11. As shown in FIG. 48, the shell 11 includes a shell body 111 and a shell cover 112. The shell cover 112 is provided on the shell. In the case of the open end of the housing 111, even if the first pole 12 is located at the closed end of the housing 111, there is no need to worry about the difficulty in welding the conductive part 22 and the first pole 12 from the inside of the housing 11, because it can The conductive part 22 and the first pole 12 are welded from the outside of the housing 11, so that the first pole 12 can be provided at the closed end of the housing 111, thereby improving the connection stability and stability of the housing 111 and the housing cover 112. reliability.

When the above-mentioned second receiving groove 12120 is opened in the first pole 12, the conductive part 22 and the first pole 12 can be welded and combined from the outside of the housing 11 through the opening of the second receiving groove 12120. As shown in Figure 48, for the case where the housing 11 includes a housing body 111 and a housing cover 112, and the housing cover 112 is located at the open end of the housing body 111, there is no need to worry even if the first pole 12 is located at the closed end of the housing body 111. The problem that it is difficult to weld the conductive part 22 and the first pole 12 from the inside of the casing 11 is because the conductive part 22 and the first pole 12 can be welded from the outside of the casing 11 , so that the first pole can be welded. The column 12 is provided at the closed end of the housing 111 to improve the stability and reliability of the connection between the housing 111 and the housing cover 112 .

Of course, with reference to FIG. 49 , in other embodiments of the present application, all the first poles 12 can also be provided on the housing cover 112 as required. This facilitates the assembly of the first pole 12 and the housing cover 112, which is not limited in this embodiment.

In addition, with reference to FIGS. 50 to 52 , in the embodiment of the present application, when there are multiple first poles 12 , the first poles 12 can also be distributed on two surfaces on different sides of the housing 11 . For example, there are a plurality of first poles 12 and they are distributed on the adjacent two side surfaces of the housing 11 . For example, there are a plurality of first poles 12 and they are distributed on the opposite side surfaces of the housing 11 .

When the first poles 12 are respectively provided on the opposite sides of the housing 11 , the active material coating part 21 can protrude the conductive part 22 from the position close to the first pole 12 on each side, and the conductive part 22 is adjacent to the first pole 12 . The first pole 12 on the same side is matched and connected, thereby improving the problem that the tab portion 221 is pulled by the first pole 12 on the same side, causing the tab portion 221 and the active material coating portion 21 to crack, thereby improving the battery cell quality. 10 reliability. It is worth noting that the first poles 12 on both sides can be the same or different, and the connection methods between the first poles 12 and the conductive portion 22 on both sides can be the same or different. There are no restrictions here.

Of course, in other embodiments of the present application, the first pole 12 may also be disposed on the side surface with the largest area of the housing 11 . For another example, in some optional embodiments of the present application, the first pole 12 may be located on the top surface of the housing 11 . For another example, in some optional embodiments of the present application, the first pole 12 may be located on the bottom surface of the housing 11, and so on. When the first pole 12 is located on the bottom surface of the housing 11 , the accommodating portion 121 can be used to accommodate the electrolyte, thereby improving the cycle life of the battery cell 10 . In addition, when the first pole 12 is located on the bottom surface of the housing 11 and the bracket 3 is located at the bottom of the active material coating part 21, the contact area between the bracket 3 and the active material coating part 21 can be increased, thereby reducing stress. Concentrate the problem and eliminate other supporting structural members.

43 , in some embodiments of the present application, the housing 11 has a pressure relief portion 16 . The specific structure of the pressure relief portion 16 is not limited. For example, it can be an explosion-proof valve or a weak portion, etc., and can be used to relieve pressure when the pressure in the battery cell 10 is high, so as to improve the reliability of the battery cell 10 .

Alternatively, the pressure relief part 16 and the first pole 12 may be located on the same side surface of the housing 11 . This facilitates processing and assembly. Or alternatively, the pressure relief portion 16 and the first pole 12 can also be separated on opposite side surfaces of the housing 11 . Therefore, space can be saved, the volume of the first pole 12 can be increased, and the adverse effects on the first pole 12 when the pressure relief part 16 releases pressure can be reduced.

Please refer to FIG. 48 and FIG. 53 again. In the embodiment of the present application, the pressure relief part 16 can also be provided on the shell cover 112 as required. Since the shell cover 112 does not need to bear the function of installing the first pole 12, and the connection position between the shell cover 112 and the housing 11 is less affected by vibration during the charging and discharging process of the battery cell 10, it is not easy to crack, so that the thickness of the shell cover 112 The shell is relatively thin, which makes it easier to process and manufacture the pressure relief part 16. For example, it is convenient to form the pressure relief part 16 directly on the shell cover 112 by integral scoring, so as to fully improve the performance of the battery cell 10. Manufacturability. It is worth noting that in this embodiment, the first pole 12 can be provided on the housing body 111 or the housing cover 112, which is not limited here. For example, the pressure relief part 16 can be integrally formed with the shell cover 112, thereby facilitating processing, simplifying assembly, improving production efficiency, and reducing costs.

Please refer to FIGS. 3-5, 18 and 23-24 again to describe the battery cell 10 according to the specific embodiment of the present application.

Referring to FIGS. 3 to 5 , the battery cell 10 is in the shape of a rectangular parallelepiped, and the height direction of the battery cell 10 is the first direction Z, the length direction of the battery cell 10 is the second direction X, and the thickness direction of the battery cell 10 is the third direction. Three directions Y. The battery cell 10 includes a case 11. The case 11 includes a case body 111 and a case cover 112. The case body 111 has a square annular structure. One end of the case body 111 is open along the first direction Z, and the other end along the first direction Z is open. Closed, the shell cover 112 covers the open position of the shell body 111 .

Referring to FIGS. 3-5 , the closed end of the housing 111 is provided with two poles along the first direction Z, and the two poles are spaced apart along the second direction X to be respectively a positive pole and a negative pole. Both poles are the first pole 12 provided with a receiving portion 121. The receiving portion 121 includes a second receiving groove 12120. Specifically, the first pole 12 includes a second end wall 12121 and a second side wall 12123. The two end walls 12121 are located on the side of the second side wall 12123 close to the shell cover 112. The second end wall 12121 and the second side wall 12123 surround a second receiving groove 12120. The first pole 12 is away from the shell cover 112. The surface on the side is the pole outer end face 123. The slot of the second receiving groove 12120 is formed on the pole outer end face 123. The second end wall 12121 is provided with a first through hole 12130. The first through hole 12130 is located on the second end wall 12121. A position close to the second side wall 12123.

Referring to Figures 5 and 18, the battery cell 10 also includes a battery core assembly 2. The battery core assembly 2 includes an active material coating part 21 and a tab part 221. The active material coating part 21 is accommodated in the housing 11, and the tab part 221. The portion 221 extends into the second receiving groove 12120 through the first through hole 12130 and is welded to the second end wall 12121 to electrically connect the active material coating portion 21 and the first pole 12 through the tab portion 221 .

18, 23 and 24, the first cover plate 13 is embedded in the slot of the second receiving groove 12120, so that after the welding of the tab part 221 and the second end wall 12121 is completed, the first cover plate 13 cooperates with the first pole 12 to close the slot of the second receiving groove 12120. The first cover 13 and the first pole 12 are welded to form an electrical connection. Thereafter, when the bus component is used to electrically connect the battery cells 10 to the battery cells 10 , the bus component can be welded to the first cover 13 to achieve electrical connection with the first pole 12 .

In the above technical solution, on the one hand, the first pole 12 is provided with the second receiving groove 12120, which can reduce the weight of the first pole 12 to a certain extent, thereby improving the weight energy density of the battery cell 10 and the battery 100; on the other hand, On the other hand, since the notch of the second receiving groove 12120 is formed on the outer end surface 123 of the pole, and the outer end surface 123 of the pole is the surface of the first pole 12 away from the active material coating part 21, so that the second receiving groove 12120 is formed on the outer end surface 123 of the pole. The groove 12120 may be open toward a direction away from the active material coating part 21 , so that when at least part of the tab part 221 is accommodated in the second accommodation groove 12120 , it can be easily realized through the notch of the second accommodation groove 12120 The pole lug 221 is stored and arranged, and the welding operation of the pole lug 221 and the first pole 12 can be easily realized through the notch of the second accommodation groove 12120 , thereby reducing the production difficulty of the battery cell 10 and improving the efficiency of the battery cell 10 . The production efficiency of the battery cell 10.

Moreover, since the opposite pole lug 221 and the first pole 12 can be welded from the outside of the casing 11 , the first pole 12 can be disposed on the closed end of the casing 111 , so that when the battery cell 10 is used In a vibrating environment, the amplitude of the connection between the shell body 111 and the shell cover 112 is small, and the connection position between the shell body 111 and the shell cover 112 is not easy to crack, which can improve the reliability of the battery cell 10 and can help reduce the size of the shell body. The wall thickness is 111, which can reduce the cost and weight, and is conducive to the miniaturization of the battery cell 10.

At the same time, since the second accommodating groove 12120 can communicate with the interior of the casing 11 through the first through hole 12130, the second accommodating groove 12120 can also serve as a buffer and temporary storage structure for the electrolyte, so that the casing 11 can accommodate more Electrolyte, since the electrolyte will be lost during the charging and discharging process of the battery cell 10, when there is more electrolyte, the service life of the battery cell 10 can be extended; and also because the second accommodation groove 12120 can be connected to the battery cell 12120 through the first through hole 12130. The interior of the casing 11 is connected, and the second receiving groove 12120 can also be used as a receiving and buffering structure for the gas generated inside the battery cell assembly 2 to reduce the expansion of the battery cell 10 and improve the reliability and stability of the battery cell 10 .

In some embodiments, with reference to FIG. 74 and FIG. 75 , the battery cell 10 further includes an outer insulating member 5 , and the outer insulating member 5 is wrapped around the case 11 . In this solution, the outer insulating member 5 plays an insulating role and is used to separate the housing 11 from external components and play an insulating role. For example, the outer insulating member 5 is a blue film.

In some embodiments, with reference to FIG. 74 , the housing 111 has a first wall 110 , the first wall 110 is formed with a mounting hole 113 , the pole body 1201 is disposed in the mounting hole 113 , and the battery cell 10 also includes a cover covering the first wall 110 The outer patch 9 of the outer insulating member 5 includes an outer insulating film 52. The outer insulating film 52 is an integrated diaphragm. The outer insulating film 52 has a connecting portion 51. The connecting portion 51 extends to the outside of the first wall 110 and is connected to the outer insulating film 52. Tablet 9 is connected.

In the above technical solution, the connecting portion 51 can be overlapped with the patch 9 along the axial direction of the mounting hole 113 to facilitate the connection between the connecting portion 51 and the patch 9 . At this time, the outer insulating film 5 and the patch 9 can at least connect the third The first pole 12 on a wall 110 is separated from the case 11 , thereby improving the insulation reliability between the first pole 12 and the case 11 , thereby improving the use reliability of the battery cell 10 . For example, in the examples of FIGS. 74 and 75 , the connecting portion 51 may extend in an annular shape around the outer periphery of the first wall 110 , so that the outer insulating member 5 can be wrapped around all other walls of the housing 11 except the first wall 110 . , the connecting part 51 is provided between the patch 9 and the first wall 110 , so that the patch 9 can play a certain protective role in the connection between the connecting part 51 and the patch 9 .

Optionally, the outer insulating member 5 is adhesively connected to the housing 11, and the patch 6 is adhesively connected to the first wall 11a.

In some embodiments, the first pole 12 has a solid structure, and the second welding portion 72 is formed on the portion of the first pole 12 located outside the housing 11. In this way, the structure of the first pole 12 is simple and convenient. processing.

In some embodiments, the minimum distance between the edge of the outer insulating film 52 and the first pole 12 is greater than or equal to 3 mm. Then, the creepage distance between the first pole 12 and the case 11 can be greater than or equal to 3 mm, which is beneficial to improving the insulation withstand voltage performance between the first pole 12 and the case 11 . For example, the minimum distance t between the connecting part 51 and the pole 12 may be 3 mm, 4 mm, 4.7 mm, 5 mm, or 5.2 mm, etc.

In some embodiments, as shown in FIGS. 56-60 and 66 , the plane where the cross section of the mounting hole 113 is located is the projection plane, and the projection of the first welding portion 71 on the projection plane is along the direction perpendicular to the projection plane. The area is greater than or equal to 0.1% of the projected area of the first wall 110 on the projection plane.

In the above technical solution, the cross section of the mounting hole 113 is perpendicular to the axial direction of the mounting hole 113 , and the projection direction in the above conditions is parallel to the axial direction of the mounting hole 113 , then the projection of the first welding portion 71 on the projection plane The area can be understood as the projected area of the connection area between the conductive part 22 and the pole body 1201 on the projection surface, then the projected area of the first welding part 71 on the projection surface can reflect the connection between the conductive part 22 and the pole body 1201 The area size of the area, and the projected area of the first welding part 71 on the projection surface meets the above conditions, the equivalent resistance between the conductive part 22 and the pole body 1201 can be reduced to a certain extent, and the first pole can be improved. The overcurrent area of 12 improves the overcurrent capacity of the first pole 12, which is beneficial to improving the charging speed of the battery cell 10, improving the fast charging performance of the battery cell 10, and at the same time, to a certain extent, it is also beneficial to improving the pole Thermal diffusion capacity of 12.

In the above technical solution, by setting the projected area of the first welding portion 71 between the conductive portion 22 and the pole body 1201 on the projection surface to be greater than or equal to 0.1% of the projected area of the first wall 110 on the projection surface, conductivity is achieved. The effective flow area between the conductive part 22 and the pole body 1201 is greater than or equal to 0.1% of the projected area of the first wall 110 on the projection surface, so as to increase the effective flow area between the conductive part 22 and the pole body 1201 and improve the third The overflow area of the first pole 12 improves the overcurrent capacity of the first pole 12, which is beneficial to increasing the charging speed of the battery cell 10, and at the same time, to a certain extent, is also beneficial to improving the heat diffusion capability of the first pole 12. , lowering the overcurrent temperature of the first pole 12 , thereby helping to reduce the risk of runaway of the battery cell 10 .

In some embodiments, along the direction perpendicular to the projection surface, the projected area of the first welding portion 71 on the projection surface is greater than or equal to 0.15% of the projected area of the first wall 110 on the projection surface.

In the above technical solution, by setting the orthogonal projected area of the first welding part 71 on the projection surface to be greater than or equal to 0.15% of the orthogonal projected area of the first wall 110 on the projection surface, the conductive part 22 and the pole body 1201 can be further improved. The effective flow area between them is beneficial to improving the fast charging performance of the battery cell 10 .

In some embodiments, the projected area of the first welding portion 71 on the projection plane is greater than or equal to 5 mm ² . For example, the projected area of the first welding portion 71 on the projection plane may be 5mm ² , 6mm ² , 8mm ² , 9mm ² , or 10mm ² or the like.

In the above technical solution, by setting the projected area of the first welding portion 71 on the projection surface to be greater than or equal to 5 mm ² , the overcurrent capability and thermal diffusion capability of the first pole 12 can be effectively improved.

For example, in the example of FIG. 59 , the projection of the first welding portion 71 on the projection plane extends into a long strip (the corresponding weld seam is a spiral strip), and the projection of the first welding portion 71 on the projection plane extends along a straight line. Taking extension as an example, the length of the projection of the first welding part 71 on the projection surface is greater than or equal to 10 mm, and the width of the projection of the first welding part 71 on the projection surface is greater than or equal to 5 mm; of course, the projection of the first welding part 71 on the projection surface The projection on the projection surface may also extend along a curve (including but not limited to smooth curves and polygonal lines). For example, the projection of the first welding portion 71 on the projection surface extends into a closed ring shape (such as a circular ring, a polygonal ring, etc.). In addition, the shape of the projection of the first welding portion 71 on the projection plane may also be a solid circle.

Furthermore, the projected area of the first welding portion 71 on the projection plane is greater than or equal to 7 mm ² . For example, the projected area of the first welding part 71 on the projection plane may be 7mm ² , 7.8mm ² , 9.5mm ² , or 11mm ^{2 ,} etc.

For example, assuming that the shape of the projection of the first welding part 71 on the projection plane is a solid circle, the diameter of the corresponding circle projected by the first welding part 71 on the projection plane is greater than or equal to 3 mm.

In some embodiments, along the direction perpendicular to the projection plane, the overlapping portion of the conductive part 22 and the pole body 1201 is the weldable area of the conductive part 22; that is, the weldable area of the conductive part 22 is perpendicular to the pole body 1201. Overlapping in the direction of the projection surface, or in the direction perpendicular to the projection surface, the projection of the weldable area of the conductive part 22 on the projection surface at least partially overlaps with the projection of the pole body 1201 on the projection surface; then the conductivity The weldable area of the portion 22 can be understood as the area provided by the conductive portion 22 that can be welded to the pole body 1201. Then the area of the weldable area must be greater than or equal to the orthogonal projected area of the first welding portion 71 on the projection plane.

Wherein, along the direction perpendicular to the projection surface, the projected area of the first welding part 71 on the projection surface is greater than or equal to 20% of the area of the weldable area of the conductive part 22, then the projection of the first welding part 71 on the projection surface The area has an appropriate proportion to facilitate the welding operation between the conductive part 22 and the pole body 1201 on the premise of appropriately improving the current flow capacity and heat diffusion capacity of the first pole 12 .

For example, the orthogonal projected area of the first welding part 71 on the projection plane is 20%, 25%, 35%, 40%, 50%, or 60% of the area of the weldable area of the conductive part 22.

In some embodiments, along the direction perpendicular to the projection surface, the projected area of the first welding portion 71 on the projection surface is greater than or equal to 30% of the area of the weldable area of the conductive portion 22 .

In the above technical solution, by setting the orthogonal projected area of the first welding part 71 on the projection surface to be greater than or equal to 30% of the area of the weldable area of the conductive part 22, it is conducive to further balancing the overcurrent capability of the first pole 12 and the Convenience of welding operations. For example, the orthogonal projected area of the second welding portion 7 on the projection plane is 30%, 45%, 55%, 65%, or 70% of the weldable area of the guide portion 22 .

In some embodiments, the cross-section of the mounting hole 113 is the projection plane, and in the direction perpendicular to the projection plane, the overlapping portion of the second converging portion 2213 and the first pole 12 is the weldable area of the pole portion 221 , and the pole portion 221 is weldable. The weldable area of the pole portion 221 overlaps with the first pole 12 in a direction perpendicular to the projection surface, or in other words, along the direction perpendicular to the projection surface, the orthographic projection of the weldable area of the pole lug portion 221 on the projection surface overlaps with that of the first pole 12 . The orthographic projection of a pole 12 on the projection plane at least partially overlaps; then the weldable area of the pole lug 221 can be understood as the area provided by the pole lug 221 that can be welded to the first pole 12, then the pole lug 221 can be welded to the first pole 12. The area of the weldable area 221 must be greater than or equal to the orthogonal projected area of the first welding portion 71 on the projection plane.

The area of the weldable area of the pole tab 221 is greater than or equal to 40% of the total area of the pole tab 221 , so that the pole tab 221 can provide enough weldable area to facilitate the lifting of the first pole 12 . It lays the foundation for flow ability and heat diffusion ability. For example, the area of the weldable area of the tab portion 221 is 40%, 45%, 50%, 65%, or 70% of the total area of the tab portion 221, and so on.

In some embodiments, the area of the weldable area of the tab portion 221 is greater than or equal to 60% of the total area of the tab portion 221 . In the above technical solution, by setting the area of the weldable area of the tab portion 221 to be greater than or equal to 60% of the total area of the tab portion 221, it is convenient to further enable the tab portion 221 to provide sufficient weldable area for lifting. The first pole 12 lays the foundation for its overcurrent capability and thermal diffusion capability. For example, the area of the weldable area of the tab portion 221 is 60%, 68%, 72%, or 80% of the total area of the tab portion 221, and so on.

In some embodiments, as shown in FIGS. 62 to 66 , the conductive part 22 includes a tab part 221 and an adapter piece 222 . The connection and arrangement of the adapter piece 222 refer to the above. In the direction perpendicular to the projection plane, the adapter piece 222 is The overlapping portion of the piece 222 with the first pole 12 is the weldable area of the adapter piece 222. The weldable area of the adapter piece 222 overlaps with the first pole 12 in a direction perpendicular to the projection plane, or in other words, along In the direction perpendicular to the projection plane, the orthographic projection of the weldable area of the adapter piece 222 on the projection plane at least partially overlaps with the orthographic projection of the first pole 12 on the projection plane; then the weldable area of the adapter piece 222 can be If the adapter piece 222 is immediately provided with an area that can be welded to the first pole 12 , then the area of the weldable area of the adapter piece 222 must be greater than or equal to the orthogonal projected area of the first welding portion 71 on the projection surface.

The area of the weldable area of the adapter piece 222 is greater than or equal to 1/12 of the area of the adapter piece 222 , so that the adapter piece 222 can provide enough weldable area to facilitate the lifting of the first pole 12 . It lays the foundation for flow ability and heat diffusion ability.

For example, the area of the weldable area of the adapter piece 222 is 1/11, 1/10, 1/9, or 1/8 of the total area of the adapter piece 222, and so on.

In some embodiments, the tab portion 221 is indirectly electrically connected to the first pole 12 through the adapter piece 222, and the weldable area of the conductive portion 22 is the weldable area of the adapter piece 222, along the direction perpendicular to the projection plane. direction, the projected area of the first welding portion 71 on the projection plane is greater than or equal to 20% of the area of the weldable area of the adapter piece 222 .

In some embodiments, the area of the weldable area of the adapter piece 222 is greater than or equal to 1/10 of the area of the adapter piece 222 .

In the above technical solution, the area of the weldable area of the adapter piece 222 is set to be greater than or equal to 1/10 of the area of the adapter piece 222, so that the adapter piece 222 can further provide sufficient weldable area to enhance the first pole. The flow capacity and heat diffusion capacity of column 12 lay the foundation. For example, the area of the weldable area of the adapter piece 222 is 1/10, 1/7, 1/6, or 1/5 of the total area of the adapter piece 222, and so on.

In some embodiments, as shown in Figure 56, all the first poles 12 of the battery cell 10 are disposed on the same wall of the housing 11, then all the first poles 12 are disposed on the first wall 110, This is so that the welding of the active material coating part 21 and the corresponding first pole 12 can be performed on the same side of the housing 11 to simplify the operation convenience.

It can be understood that when all the first poles 12 of the battery cells 10 are disposed on the first wall 110 , the first wall 110 can be the wall with the largest area of the housing 11 , or the area of the first wall 110 is smaller than The area of the housing 11 is the area of the largest wall.

In some embodiments, as shown in Figure 56, the housing 11 includes a housing body 111 and a housing cover 112. One end of the housing body 111 is open, the housing cover 112 is matched with the open end of the housing body 111, and the pole posts 12 are all located on the housing. The end of the body 111 away from the shell cover 112. The end of the housing 111 away from the housing cover 112 can be understood as referring to the end of the housing 111 opposite to the housing cover 112. When the battery cell 10 is assembled, the battery assembly 2 will enter the housing 111 from the open end of the housing 111. At this time, the conductive part 22 can contact and install the pole post 12 along the direction in which the battery core assembly 2 enters the case. In this process, the installation of the conductive part 22 and the pole post 12 is relatively easy, which can improve the assembly efficiency.

Alternatively, the shell cover 112 may be formed as a flat plate structure or as a cover structure open toward one end of the shell body 111 .

In some embodiments, all the first poles 12 of the battery cell 10 are respectively provided on different walls of the housing 11 to facilitate flexible arrangement of the battery cell 10 and other electrical connection components.

Specifically, as shown in Figure 56, the housing 11 has a second wall 120. The second wall 120 can be opposite and spaced apart from the first wall 110, or arranged at an angle. The second wall 120 is formed with a second mounting hole. 114. In this case, the plurality of first poles 12 may include first polarity poles 12A and second polarity poles 12B with different polarities, then the first polarity poles 12A are disposed in the mounting holes 113, The second mounting hole 114 is provided with a second polarity post 12B that is opposite in polarity to the first polarity post 12A. Likewise, one of the first polarity pole 12A and the second polarity pole 12B is a positive pole and the other is a negative pole, and the second wall 120 may be adjacent to the first wall 110 and not parallel, or The second wall 120 is not adjacent to the first wall 110. At this time, the second wall 120 and the first wall 110 may be parallel or non-parallel. The first polarity pole 12A and the second pole are respectively provided on different walls of the housing 11. Sex pole 12B.

More specifically, all the first poles 12 of the battery cells 10 are respectively provided on two opposite walls of the housing 11 , or all the first poles 12 of the battery cells 10 are respectively provided on the housing 11 on two adjacent walls; of course, all the first poles 12 of the battery cell 10 can also be respectively provided on three or more walls of the housing 11 .

At this time, the battery core component 2 includes one active material coating part 21 or multiple active material coating parts 21 that are electrically connected; the battery core component 2 also includes two conductive parts 22 with opposite polarities. Among the two conductive parts 22 One of the two conductive parts 22 is electrically connected to the first polarity pole 12A, and the other of the two conductive parts 22 is electrically connected to the second polarity pole 12B through a first welding part 71 . It can be seen that when the battery core assembly 2 includes multiple active material coating parts 21, the multiple active material coating parts 21 may be connected in parallel to the first polarity pole 12A on the first wall 110 and the third polarity pole 12A on the second wall 120. between the two polar poles 12B to increase the capacity of the battery cell 10 .

Taking the cross-section of the second mounting hole 114 as the projection plane, along the direction perpendicular to the projection plane, the projected area of the first welding portion 71 corresponding to the second polarity pole 12B on the projection plane is greater than or equal to the third The projected area of the second wall 120 on the projection surface is 0.03% to increase the flow area and flow capacity of the second polarity pole 12B on the second wall 120, which further helps to increase the charging speed of the battery cell 10. At the same time, it is also beneficial to reduce the overcurrent temperature of the second polarity pole 12B, thereby further reducing the risk of runaway of the battery cell 10 .

Obviously, regardless of the number of active material coating portions 21 of the battery core assembly 2, the two conductive portions 22 of each battery core assembly 2 are electrically connected to the corresponding active material coating portion 21, and the two conductive portions 22 of each battery core assembly 2 are One of the conductive parts 22 is electrically connected to the first polarity pole 12A on the first wall 110 through the first welding part 71 , and the other conductive part 22 is electrically connected to the second polarity pole 12B on the second wall 120 through another The first welding part 71 is electrically connected.

Therefore, in the above technical solutions of the present application, the arrangement of the first polarity poles 12A and the second polarity poles 12B is relatively flexible, so that the battery cells 10 can meet different layout requirements.

In some embodiments, as shown in FIGS. 70-73 , the mounting hole 113 includes a plurality of spaced apart holes 1131 , the first polarity pole 12A includes a plurality of first poles 12 , and the plurality of first poles 12 are provided in the plurality of holes 1131 in one-to-one correspondence; the battery core assembly 2 includes a plurality of active material coating parts 21, and the conductive part 22 includes a plurality of conductive sub-sections connected to the plurality of active material coating parts 21 in a one-to-one correspondence. , each conductive segment is electrically connected to a first pole 12 through a welding segment 71;

Taking the plane where the cross section of the mounting hole 113 is located as the projection plane, along the direction perpendicular to the projection plane, the sum of the projected areas of the plurality of welding parts 71 on the projection plane is greater than or equal to the projected area of the first wall 110 on the projection plane. 0.1% to achieve an improvement in the 12A overcurrent capability of the first polarity pole.

At this time, the arrangement of the second polarity poles 12B of the battery cell 10 can be set according to actual requirements. For example, in the example of FIG. 71 , a plurality of first poles 12 are arranged in a plurality of branch holes 1131 of the mounting hole 113 in one-to-one correspondence. The housing 11 is also formed with a second mounting hole 114 , and the second mounting hole 114 is also formed in the example of FIG. 71 . It includes a plurality of spaced holes 1131. The second polarity pole 12B includes a plurality of second poles 15. The plurality of second poles 15 are arranged in the plurality of holes 1131 of the second mounting hole 114 in one-to-one correspondence. ; At this time, the second polarity pole 12B and the first polarity pole 12A can be disposed on the same wall of the housing 11 or on different walls.

Of course, in other embodiments of the present application, the mounting hole 113 includes a branch hole 1131, the first polarity pole 12A includes a first pole 12, the second mounting hole 114 also includes a branch hole 1131, and the second polarity pole 12A also includes a branch hole 1131. The pole 12B includes a second pole 15 . It can be understood that, for the battery cell 10 , the number of the first poles 12 and the number of the second poles 15 may be equal or different.

In some embodiments, all the poles are respectively provided on two opposite walls of the housing 11, and poles are respectively provided on the first wall 110 and the wall of the housing 11 opposite to the first wall 110, so as to facilitate the realization of the poles. Flexible settings.

In some embodiments, as shown in FIGS. 67-72 , the outer contour of the cross-section of the first polar pole 12A is rectangular, racetrack-shaped, or elliptical, and the cross-section of the first polar pole 12A can be the same as The axial direction of the mounting hole 113 is vertical, which facilitates flexible setting of the outer contour of the first polarity pole 12A. At the same time, the length of the cross section of the first polarity pole 12A is greater than its width, which is conducive to making the first polarity pole 12A 12A and the first wall 110 achieve a good match in the length direction of the cross-section of the first polarity pole 12A and the width direction of the cross-section of the first polarity pole 12A. For example, the first wall 110 is in the first polarity pole 12A. The length in the cross-sectional length direction is greater than the width of the first wall 110 in the cross-sectional width direction of the first polar pole 12A, so that the first polar pole 12A that can be arranged on the first wall 110 can be increased to a certain extent. The cross-sectional area is conducive to increasing the cross-sectional area of the first polar pole 12A within the limited arrangement area on the first wall 110, which is conducive to increasing the flow area of the first polar pole 12A and improving the The overcurrent capability of the first polarity pole 12A improves the heat diffusion capability of the first polarity pole 12A, which is beneficial to increasing the charging speed of the battery cell 10 .

At the same time, the outer contour of the cross-section of the second polarity pole 12B, which is opposite to the polarity of the first polarity pole 12A, is rectangular, racetrack-shaped, or elliptical, which is also conducive to making the second polarity pole 12B and The corresponding walls of the housing 11 (such as the first wall 110 or the second wall 120, etc.) achieve a good match in the length direction of the cross-section of the second polarity pole 12B and the width direction of the cross-section of the second polarity pole 12B, The effective arrangement area of the corresponding wall of the housing 11 is fully utilized to increase the cross-sectional area of the second polarity pole 12B, which is conducive to increasing the overcurrent capacity of the second polarity pole 12B and is conducive to improving the battery cell. Body 10 charging speed.

The rectangle in the above embodiments of the present application can be understood in a broad sense. The four corners of the rectangle can be right-angled transitions or rounded corner transitions. The racetrack shape can be understood as including two parallel line segments and two halves connecting the two line segments. Round, such as a runway shape. It can be understood that the shape of the cross-sectional outer contour of the second polarity pole 12B of the battery cell 10 may be the same as or different from the shape of the cross-sectional outer contour of the first polarity pole 12A. 12A and the second polarity pole 12B may be located on the same wall of the housing 11 , or may be located on different walls of the housing 11 .

In some embodiments, as shown in Figures 56, 67-72, in the cross-section of the first polarity pole 12A, the size of the first polarity pole 12A in the first direction X is greater than or equal to the Three times the size of a polar pole 12A in the second direction Y, the first direction The first wall 110 is well matched in the first direction Increasing the cross-sectional area of the first polarity pole 12A facilitates the construction of the first polarity pole 12A into a "super large pole structure", which is beneficial to increasing the flow area of the first polarity pole 12A. Overcurrent capability and heat dissipation capability.

As shown in Figures 56, 67-72, in the cross-section of the second polarity pole 12B, the size of the second polarity pole 12B in the first direction X is greater than or equal to the second polarity pole 12B. Three times the size in the second direction Y, the polarity of the second polarity pole 12B is opposite to the polarity of the first polarity pole 12A. At this time, the second polarity pole 12B is the same as the first polarity pole. The post 12A can be located on the same wall of the housing 11, or the second polarity post 12B and the first polarity post 12A can be located on two opposite walls of the housing 11, which is advantageous for the second polarity post 12B and the first polarity post 12A to be located on opposite sides of the housing 11. The corresponding walls of the housing 11 are well matched in the first direction X and the second direction Y, so that the second polarity pole 12B can make full use of the arrangement area of the corresponding wall of the housing 11, which is beneficial to improving the second polarity pole 12B. flow area, flow capacity and heat diffusion capacity.

For example, the size of the first polarity pole 12A in the first direction X may be 3 times, 3.5 times, 4 times, or 4.2 times the size of the first polarity pole 12A on the second defense line. The size of the polar pole 12B in the first direction X may be 3 times, 3.5 times, 3.7 times, or 4.2 times the size of the second polarity pole 12B on the second defense line, etc.

Exemplarily, the first direction The direction may be understood as the height direction of the first polar pole 12A or the axial direction of the first polar pole 12A.

Alternatively, in the cross-section of the second polarity pole 12B, the size of the second polarity pole 12B in the axial direction of the mounting hole 113 is greater than or equal to the size of the second polarity pole 12B in the second direction Y. three times, the polarity of the second polarity pole 12B is opposite to the polarity of the first polarity pole 12A. At this time, the second polarity pole 12B and the first polarity pole 12A can be respectively located in the housing 11 The two mutually perpendicular walls are also conducive to achieving a good match between the second polarity pole 12B and the corresponding wall of the housing 11 in the axial direction of the mounting hole 113 and the second direction Y, so that the second polarity pole 12B Making full use of the arrangement area of the corresponding wall of the housing 11 is beneficial to improving the flow area, flow capacity and heat diffusion capacity of the second polarity pole 12B. The axial direction of the mounting hole 113 may be the length direction of the wall where the second polarity pole 12B is located.

In some embodiments, as shown in FIG. 56 , the size of the first wall 110 in the first direction The length direction of the cross section of the polar pole 12A is consistent, and the width direction of the first wall 110 can be consistent with the width direction of the cross section of the first polar pole 12A, so as to further align the first wall 110 with the first polarity pole. The pole posts 12A achieve good matching in the first direction X and the second direction Y, so that the first polarity pole 12A further fully utilizes the arrangement area of the first wall 110 .

Exemplarily, the first wall 110 is provided with a first polarity pole 12A and a second polarity pole 12B. The first polarity pole 12A and the second polarity pole 12B may be spaced apart along the first direction X. , so that the arrangement direction of the first polarity pole 12A and the second polarity pole 12B matches the length direction of the first wall 110, so that there is a gap between the first polarity pole 12A and the second polarity pole 12B. Have proper spacing. Of course, the second polarity pole 12B and the first polarity pole 12A can also be provided on different walls of the housing 11, so that the housing 11 has a second wall 120, and the second wall 120 is provided with a second polarity pole. Taking pole 12B as an example, if the second wall 120 is opposite to and spaced apart from the first wall 110, the size of the second wall 120 in the first direction X may be larger than the size of the second wall 120 in the second direction Y, so as to facilitate The second polarity pole 12B makes full use of the arrangement area provided by the second wall 120. If the second wall 120 and the first wall 110 are arranged at an angle, the length direction of the cross section of the second polarity pole 12B can be set to be in line with the first wall 110. The length direction of the two walls 120 is consistent, and the width direction of the cross section of the second polarity pole 12B is consistent with the width direction of the second wall 120 , which also facilitates the second polarity pole 12B to make full use of the layout area provided by the second wall 120 .

In some embodiments, as shown in FIGS. 67-72 , the first polar pole 12A includes a first portion 128 located outside the first wall 110 , the first portion 128 is annular, and in the first direction X, the first portion 128 The length of the inner ring is greater than or equal to 1/3 of the length of the first wall 110 , and the width of the inner ring of the first portion 128 in the second direction Y is greater than or equal to 3/4 of the width of the first wall 110 .

In the above technical solution, by setting the length of the inner ring of the first part 128 to be greater than or equal to 1/3 of the length of the first wall 110, and the width of the inner ring of the first part 128 to be greater than or equal to 3/4 of the width of the first wall 110, it is convenient to The first polarity pole 12A can provide a larger area for electrical connection with the bus component, so as to further enhance the overcurrent capability of the first polarity pole 12A.

For example, the inner ring length of the first part 128 is greater than or equal to 50 mm, and the inner ring width of the first part 128 is greater than or equal to 30 mm.

In some embodiments, the first polarity pole 12A includes a second portion 129 located inside the first wall 110 , and in the first direction X, the length of the second portion 129 is greater than or equal to the length of the first wall 110 . 1/3, in the second direction Y, the width of the second portion 129 is greater than or equal to 3/4 of the width of the first wall 110 .

In the above technical solution, by setting the inner ring length of the second part 129 to be greater than or equal to 1/3 of the length of the first wall 110, the inner ring width of the second part 129 is greater than or equal to 3/4 of the width of the first wall 110. , so that the first polarity pole 12A can provide a larger area for electrical connection with the conductive portion 22, so as to further improve the overcurrent capability of the first polarity pole 12A.

For example, the length of the second part 129 is greater than or equal to 50 mm, and the width of the second part 129 is greater than or equal to 30 mm.

As shown in Figure 2, an embodiment of the present application provides a battery 100, including the aforementioned battery cell 10.

As shown in FIGS. 58 and 60 , in some embodiments, the battery 100 includes a battery cell 10 and a bus component 30 .

The number of battery cells 10 is multiple. The bus component 30 is electrically connected to the first poles 12 of at least two battery cells 10, and the first poles 12 of the same polarity of each battery cell 10 are electrically connected to the bus component 30 through the second welding portion 72. The second welding portion 72 is formed on the first cover plate 13 . The housing 11 includes a first wall 110. The first wall 110 is formed with a mounting hole 113. The pole body 1201 is disposed in the mounting hole 113. On the cross section of the mounting hole 113, the orthographic projection area of the second welding portion 72 is larger than Or equal to 0.2% of the orthogonal projected area of the first wall 110 .

The definition of the cross-section of the mounting hole 113 refers to the above, and can be understood as the orthogonal projection area of the connection area between the bus component 30 and the corresponding first pole 12 on the cross-section of the mounting hole 113. Then the second welding portion 72 is The orthogonal projected area on the cross section of the mounting hole 113 can reflect the area of the connection area between the bus component 30 and the corresponding first pole 12 , and the orthogonal projected area of the second welding part 72 on the cross section of the mounting hole 113 satisfies the above requirements. Conditions, the equivalent resistance between the bus component 30 and the first pole 12 can be reduced to a certain extent, the overflow area of the first pole 12 can be increased, and the overcurrent capacity of the first pole 12 can be improved. It is beneficial to increase the charging speed of the battery cell 10 and improve the fast charging performance of the battery cell 10. It is also beneficial to improve the heat diffusion capability of the first pole 12 to a certain extent.

In the above technical solution, the orthogonal projected area of the second welding portion 72 between the bus part 30 and the corresponding first pole 12 on the cross section of the mounting hole 113 is greater than or equal to the orthogonal projected area of the first wall 110 0.2%, so that the effective flow area between the bus part 30 and the corresponding first pole 12 is greater than or equal to 0.2% of the orthographic projection area of the first wall 110, so as to improve the effective flow area between the bus part 30 and the first pole 12 The flow area increases the overflow area of the first pole 12 and the overcurrent capacity of the first pole 12, which is beneficial to increasing the charging speed of the battery cell 10 and, to a certain extent, is also beneficial to improving the first pole 12 The heat dissipation ability reduces the overcurrent temperature of the first pole 12, which is beneficial to reducing the risk of the battery cell 10 running out of control.

It can be understood that there may be multiple poles, namely the first polarity pole 12A and the second polarity pole 12B. The second polarity pole 12B and the first polarity pole 12A have opposite polarities. They can be respectively positive pole and negative pole.

Optionally, the bus part 30 and the first pole 12 are laser welded to form the second welding part 72; but it is not limited thereto.

In some embodiments, on the cross section of the mounting hole 113 , the orthogonal projected area of the second welding portion 72 is greater than or equal to 0.4% of the orthogonal projected area of the first wall 110 to further enhance the connection between the bus part 30 and the first pole. The effective flow area between the battery cells 12 is beneficial to improving the fast charging performance of the battery cell 10 .

In some embodiments, along the direction perpendicular to the cross-section of the mounting hole 113 , the overlapping portion of the bus component 30 with the pole body 1201 of the same polarity is the weldable area of the bus component 30 , that is, the weldable area of the bus component 30 Overlapping with the pole body 1201 in the direction perpendicular to the projection surface, or in other words, along the direction perpendicular to the projection surface, the projection of the weldable area of the bus part 30 on the cross section of the mounting hole 113 is consistent with the pole body 1201 when the pole body 1201 is installed. The projections on the cross-section of the hole 113 at least partially overlap; then the weldable area of the bus component 30 can be understood as the area provided by the bus component 30 that can be welded to the pole body 1201, then the area of the weldable area must be greater than or equal to The orthogonal projected area of the second welding portion 72 on the projection plane.

The orthogonal projected area of the second welding portion 72 on the cross-section of the mounting hole 113 is greater than or equal to 0.2 of the weldable area area of the bus component 30 . Then the projected area of the second welding part 72 on the projection surface has an appropriate proportion, so as to facilitate the connection between the bus part 30 and the pole body 1201 on the premise of appropriately improving the current flow capacity and heat diffusion capacity of the pole body 1201. Welding operations.

For example, the orthogonal projected area of the second welding portion 72 on the cross-section of the mounting hole 113 is 0.2, 0.25, 0.35, 0.40, 0.50, or 0.60 of the area of the weldable area of the bus component 30 , etc.

In some embodiments, the orthogonal projected area of the second welding portion 72 on the cross-section of the mounting hole 113 is greater than or equal to 0.4 of the weldable area area of the bus component 30 .

In the above technical solution, by arranging the orthographic projection area of the second welding portion 72 on the cross section of the mounting hole 113 to be greater than or equal to 0.4 of the area of the weldable area of the bus component 30, it is conducive to further balancing the current flow capacity of the pole post 12 and the Convenience of welding operations.

For example, the orthogonal projected area of the second welding portion 72 on the cross section of the mounting hole 113 is 0.4, 0.45, 0.55, 0.65, or 0.70 of the area of the weldable area of the bus component 30 .

In some embodiments, the orthographic projection of the second welding portion 72 on the cross-section of the mounting hole 113 is one of a straight line, a curve, a circle, a polygon, or an annular shape.

For example, please refer to FIG. 58 . The orthographic projection of the second welding part 72 on the cross section of the mounting hole 113 may be a circular weld. The diameter of the circular weld is greater than or equal to 5 mm, and the effective melting width W is greater than or equal to 2 mm.

In some embodiments, the area of the orthogonal projection of the second welding portion 72 on the cross-section of the mounting hole 113 may be 10 mm ² -20 mm ² . For example, the area of the orthogonal projection of the second welding portion 72 on the cross section of the mounting hole 113 may be 10mm ² , 12mm ² , 15mm 2 , 17mm ² , 19mm ^{2 ,} 20mm ² and so on.

In some embodiments, along the direction perpendicular to the cross-section of the mounting hole 113 , the overlapping portion of the bus component 30 with the first pole 12 of the same polarity is the weldable area of the bus component 30 , that is, the bus component 30 The weldable area overlaps with the first pole 12 of the same polarity in a direction perpendicular to the cross-section of the mounting hole 113, or in other words, along the direction perpendicular to the cross-section of the mounting hole 113, the weldable area of the bus component 30 is at The orthographic projection on the cross section of the mounting hole 113 at least partially overlaps with the orthographic projection of the first pole 12 of the same polarity on the cross section of the mounting hole 113; then the weldable area of the bus component 30 can be understood as the bus component 30 Provided is an area that can be welded to the first pole 12 , the area of the weldable area of the bus component 30 must be greater than or equal to the orthogonal projected area of the second welding portion 72 on the cross section of the mounting hole 113 .

The area of the weldable area of the bus component 30 is greater than or equal to 20% of the orthogonal projected area of the bus component 30 on the cross section of the mounting hole 113 . In this way, the bus component 30 can provide enough weldable area to lay the foundation for improving the flow capacity and heat diffusion capacity of the first pole 12 .

For example, the area of the weldable area of the bus component 30 is 20%, 25%, 30%, 35%, or 40% of the total area of the bus component 30, and so on.

In some embodiments, the area of the weldable area of the bus component 30 is less than or equal to 50% of the orthogonal projected area of the bus component 30 on the cross section of the mounting hole 113 . By setting the area of the weldable area of the bus component 30 to be greater than or equal to 50% of the orthogonal projected area of the bus component 30 on the cross section of the mounting hole 113, it is beneficial to further balance the current flow capacity of the first pole 12 and the convenience of welding operations. .

In some embodiments, the area of the weldable area of the bus component 30 is greater than or equal to 30% of the orthogonal projected area of the bus component 30 on the cross-section of the mounting hole 113 . By setting the area of the weldable area of the bus component 30 to be greater than or equal to 30% of the orthogonal projected area of the bus component 30 on the cross section of the mounting hole 113, it is beneficial to further balance the current flow capacity of the first pole 12 and the convenience of welding operations. .

As shown in Figure 1, an embodiment of the present application provides an electrical device 1000, including the aforementioned battery 100.

The battery 100 is used to provide electrical energy to the electrical device 1000 . The power-consuming device 1000 may be any of the aforementioned devices or systems using the battery 100 . It should be noted that, as long as there is no conflict, the embodiments and features in the embodiments of this application can be combined with each other.

The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included in the protection scope of this application.

Claims (40)

1. A battery cell, comprising:

the shell assembly comprises a shell and a first polar column, wherein the first polar column comprises a polar column body and a first cover plate, the polar column body is installed on the shell, and the first cover plate is arranged on the polar column body;

the battery cell assembly comprises an active material coating part and a conductive part connected with the active material coating part, wherein the active material coating part is accommodated in the shell, and the conductive part is connected with the pole body through a first welding part;

The first welding part is at least partially positioned on one side of the pole body, which is away from the active material coating part, and the first cover plate is used for shielding the first welding part.

2. The battery cell according to claim 1, wherein the post body has a first accommodation groove, a surface of the first post facing the active material coating portion side is a post inner end surface, a notch of the first accommodation groove is formed on the post inner end surface, and the first accommodation groove has a first end wall and a first side wall, the first end wall is located on a side of the first side wall away from the active material coating portion, at least part of the conductive portion is accommodated in the first accommodation groove, the first welding portion is provided on the first end wall, the first cover plate is engaged with the post body, and the first welding portion is covered.

3. The battery cell of claim 2, wherein the first end wall has a first countersink thereon, and wherein at least a portion of the first weld is located within the first countersink.

4. The battery cell according to claim 2 or 3, wherein the first electrode post has a first groove, a side surface of the first electrode post remote from the active material coating portion is an electrode post outer end surface, a notch of the first groove is formed on the electrode post outer end surface, and the first cover plate covers the notch of the first groove.

5. The battery cell according to claim 2, wherein the active material coating portion includes a current collector and an active material layer disposed on the current collector, the conductive portion includes a tab portion electrically connected to the current collector, the tab portion includes a plurality of tabs, the plurality of tabs converge near the current collector to form a first converging portion, the plurality of tabs converge away from the current collector and connect to form a second converging portion, the first converging portion connects the second converging portion and the active material coating portion, at least a portion of the second converging portion is received in the first receiving groove,

the second gathering portion is connected with the first end wall through the first welding portion.

6. The battery cell according to claim 2, wherein the active material coating portion includes a current collector and an active material layer disposed on the current collector, the conductive portion includes a tab portion and a transfer piece, the tab portion includes a plurality of tab pieces, the plurality of tab pieces converge near a position of the current collector to form a first converging portion, the plurality of tab pieces converge away from the position of the current collector and connect to form a second converging portion, the first converging portion connects the second converging portion and the active material coating portion, the transfer piece connects with the second converging portion, at least a portion of the transfer piece is accommodated in the first accommodating groove,

The adapter piece is connected with the first end wall through the first welding part.

7. The battery cell according to claim 5 or 6, wherein at least part of the first folded portion is accommodated in the first accommodation groove.

8. The battery cell of claim 2, wherein the housing has a mounting hole therein, the first post being mounted to the mounting hole; along the axial direction of the first pole, the depth H1 of the first accommodating groove is larger than or equal to the minimum distance H2 from the inner end surface of the pole to the mounting hole.

9. The battery cell as recited in claim 1, wherein the post body has a second receiving groove, a surface of the post body on a side remote from the active material coating portion is a post outer end surface, a notch of the second receiving groove is formed on the post outer end surface, the second receiving groove has a second end wall near the active material coating portion,

the first welding part is arranged on the second end wall, the first cover plate is matched with the pole body, and the notch of the second accommodating groove is sealed.

10. The battery cell of claim 9, wherein the conductive portion is located on a side of the second end wall that faces the active material coating portion.

11. The battery cell of claim 9, wherein the second receiving groove communicates with the interior of the case through a first through hole, the conductive portion is disposed through the first through hole and at least partially received in the second receiving groove, and the conductive portion is at least partially disposed on a side of the second end wall facing away from the active material coating portion.

12. The battery cell as recited in claim 11, wherein the second receiving groove further has a second side wall, the second side wall is located on a side of the second end wall away from the active material coating portion, the second side wall and the second end wall enclose the second receiving groove, the first through hole is opened in the second end wall,

the second end wall is provided with a second sinking groove, and at least part of the first welding part is positioned in the second sinking groove.

13. The battery cell according to claim 11 or 12, wherein the active material coating portion includes a current collector and an active material layer provided on the current collector, the conductive portion includes a tab portion electrically connected to the current collector, the tab portion includes a plurality of tabs, the plurality of tabs are converged at positions close to the current collector to form a first converging portion, the plurality of tabs are converged at positions far from the current collector and connected to form a second converging portion, the first converging portion connects the second converging portion and the active material coating portion, at least part of the second converging portion is accommodated in the second accommodation groove,

The second gathering portion is connected with the second end wall through the first welding portion.

14. The battery cell according to claim 11 or 12, wherein the active material coating portion includes a current collector and an active material layer provided on the current collector, the conductive portion includes a tab portion and a transfer sheet, the tab portion is electrically connected to the current collector, the tab portion includes a plurality of tab pieces, the tab pieces are converged at positions close to the current collector to form a first converging portion, the tab pieces are converged at positions far from the current collector to form a second converging portion, the first converging portion connects the second converging portion and the active material coating portion, the transfer sheet is connected to the second converging portion, at least part of the transfer sheet is accommodated in the second accommodating groove,

the adapter piece is connected with the second end wall through the first welding part.

15. The battery cell of claim 13, wherein at least a portion of the first furled portion is received in the second receiving groove.

16. The battery cell according to claim 13, wherein the post body is provided with a first accommodation portion having a third accommodation groove, a surface of the first post on a side facing the active material coating portion is a post inner end surface, the third accommodation groove is located on a side of the second accommodation groove near the active material coating portion, and a notch of the third accommodation groove is formed on the post inner end surface, the third accommodation groove communicates with the second accommodation groove through the first perforation, and at least a part of the first gathering portion is accommodated in the third accommodation groove.

17. The battery cell of claim 11, wherein the housing assembly further comprises a second cover plate covering the first aperture and the conductive portion within the second receiving slot.

18. The battery cell as recited in claim 9, wherein the housing has a mounting hole, the first post is mounted to the mounting hole, and a depth H3 of the second receiving groove is greater than or equal to a minimum distance H4 from an outer end surface of the post to the mounting hole in an axial direction of the first post.

19. The battery cell according to claim 1, wherein the electrode body is provided with a first receiving part having a fourth receiving groove, a surface of the electrode body on a side remote from the active material coating part is an outer end surface of the electrode, a notch of the fourth receiving groove is formed on the outer end surface of the electrode, the fourth receiving groove communicates with the inside of the case through a second penetration hole, the conductive part penetrates through the second penetration hole,

the first welding part is arranged on the hole wall of the second perforation formed by the first containing part, the first cover plate is matched with the pole body, and the second perforation is sealed.

20. The battery cell of claim 19, wherein the post body comprises a first post portion and a second post portion that are different in material and electrically connected, the second post portion is located on a side of the first post portion that is away from the active material coating portion, the first receiving portion is disposed at the first post portion or is disposed at the first post portion and the second post portion, and the first welding portion is disposed at the first post portion.

21. The battery cell according to claim 1, wherein the first cap plate is provided with a second receiving part having a fifth receiving groove, a notch of which is formed on an end surface of the first cap plate facing the active material coating part, and the fifth receiving groove has a third end wall and a third side wall, the third end wall being located at a side of the third side wall remote from the active material coating part,

at least part of the first welding part is accommodated in the fifth accommodating groove.

22. The battery cell of claim 1, wherein the first cover plate is electrically connected to the post body; or, the first cover plate is arranged in an insulating way with the pole body.

23. The battery cell of claim 1, wherein the first cover plate comprises a first conductive member and a second conductive member that are different in material, the first conductive member is mated and electrically connected with the pole body, and the second conductive member is mated and electrically connected with the first conductive member.

24. The battery cell as recited in claim 23, wherein the first conductive member has a second groove formed therein, and the second conductive member is fitted in the second groove, and a notch of the second groove is formed on a surface of the first conductive member on a side remote from the active material coating portion so that the second conductive member is exposed from the notch of the second groove.

25. The battery cell of claim 23, wherein the first cover plate has a stress relief groove thereon, the stress relief groove being located in an outer peripheral region of the first cover plate.

26. The battery cell of claim 2, further comprising:

the support is located in the shell and located on one side, close to the first pole, of the active material coating portion, an avoidance hole used for avoiding the conductive portion is formed in the support, and the conductive portion is suitable for extending to one side, far away from the active material coating portion, of the support through the avoidance hole.

27. The battery cell of claim 26, wherein the post body is provided with a first receptacle, the bracket is provided with a guide portion surrounding at least a portion forming the relief aperture, and the guide portion extends at least partially to the first receptacle.

28. The battery cell of claim 26 or 27, wherein the relief hole comprises a first hole section and a second hole section, the second hole section is located on one side of the first hole section near the active material coating portion, the cross-sectional area of the second hole section gradually increases along a direction away from the first hole section, the active material coating portion comprises a current collector and an active material layer disposed on the current collector, the conductive portion comprises a tab portion electrically connected with the current collector, the tab portion comprises a plurality of tabs, the positions of the tabs near the current collector are converged to form a first converging portion, the positions of the tabs away from the current collector are converged and connected to form a second converging portion, the first converging portion is connected with the second converging portion and the active material coating portion, at least a portion of the first converging portion is accommodated in the second hole, and the second converging portion is disposed through the first hole.

29. The battery cell of claim 26, wherein the bracket is of unitary construction; or, the support is split type structure and includes detachable first support and second support, first support with it dodges the hole to inject between the second support.

30. The battery cell according to claim 1, wherein the case has a first wall, the first wall is formed with a mounting hole, the post body is disposed in the mounting hole, a plane of the mounting hole where a cross section is located is a projection plane, and a ratio of a projection area of the first welding portion on the projection plane to a projection area of the first wall on the projection plane is in a range of 0.1% to 1% along a direction perpendicular to the projection plane.

31. The battery cell according to claim 1, wherein the housing has a mounting hole, the post body includes an integrally formed post body portion, a first limit land portion and a second limit land portion, the post body portion is disposed through the mounting hole, the first limit land portion and the second limit land portion are disposed at both ends of the post body portion along an axial direction of the mounting hole, the first limit land portion is in limit fit with an outer side of the housing, and the second limit land portion is in limit fit with an inner side of the housing, so that the post body is riveted to the housing.

32. The battery cell of claim 1, wherein the battery cell further comprises: and the outer insulating piece is wrapped outside the shell.

33. The battery cell of claim 32, wherein the housing has a first wall formed with a mounting hole, the post body is disposed in the mounting hole, the battery cell further comprises a patch covering an outer side of the first wall, the outer insulator comprises an outer insulating film, the outer insulating film is an integral membrane, the outer insulating film has a connection portion, and the connection portion extends to the outer side of the first wall and is connected with the patch.

34. The battery cell of claim 33, wherein a minimum distance between an edge of the outer insulating film and the first post is 3mm or more.

35. A battery comprising the battery cell of any one of claims 1-34.

36. The battery of claim 35, comprising:

a plurality of the battery cells;

the current collecting component is electrically connected with the first polar posts of at least two battery monomers, the first polar posts of the same polarity of each battery monomer are respectively electrically connected with the current collecting component through second welding parts, and the second welding parts are formed on the first cover plate;

The shell comprises a first wall, a mounting hole is formed in the first wall, the pole body is arranged in the mounting hole, and the orthographic projection area of the second welding part on the cross section of the mounting hole is larger than or equal to 0.2% of the orthographic projection area of the first wall.

37. The battery of claim 36, wherein the overlapping portion of the bus bar member with the same polarity of the post body in a direction perpendicular to a cross section of the mounting hole is a solderable region of the bus bar member,

and the orthographic projection area of the second welding part on the cross section of the mounting hole is more than or equal to 0.2 of the area of the weldable area of the bus component.

38. The battery of claim 36, wherein the overlapping portion of the bus member with the first pole of the same polarity in a direction perpendicular to a cross section of the mounting hole is a solderable region of the bus member,

the area of the weldable region of the bus member is greater than or equal to 20% of the orthographic projected area of the bus member on the mounting hole cross section.

39. The battery of claim 38, wherein an area of the weldable region of the bussing member is less than or equal to 50% of an orthographic projected area of the bussing member on the mounting hole cross-section.

40. An electrical device comprising a battery according to any one of claims 35-39.