CN219017861U - End cover, battery monomer, battery and electric equipment - Google Patents

Abstract

The embodiment of the application provides an end cover, a battery monomer, a battery and electric equipment. The end cap includes: the end cover body is provided with an opening; the first connecting structure comprises first metal, and is arranged on the inner side of the opening and used for being welded and connected with the electrode terminal in the opening; the second connecting structure comprises second metal, and is connected with the first connecting structure, and the second connecting structure is used for being welded and connected with the first sealing piece for sealing the opening. The technical scheme provided by the application can increase the output current of the battery, and further improve the performance of the battery.

Description

End cover, battery monomer, battery and electric equipment

Technical Field

The application relates to the technical field of batteries, in particular to an end cover, a battery monomer, a battery and electric equipment.

Background

With the increasing increase of environmental pollution, the new energy industry is receiving more and more attention. In the new energy industry, battery technology is an important factor in its development.

In the development process of battery technology, how to improve the performance of a battery is a problem to be solved in the battery technology.

Disclosure of Invention

In view of the above problems, embodiments of the present application provide an end cover, a battery unit, a battery and electric equipment, which can increase the output current of the battery, thereby improving the performance of the battery.

In a first aspect, there is provided an end cap comprising: the end cover comprises an end cover body, a cover body and a cover body, wherein the end cover body is provided with an opening; a first connection structure including a first metal, the first connection structure being disposed inside the opening for welding connection with an electrode terminal located inside the opening; and the second connecting structure comprises second metal, is connected with the first connecting structure and is used for being welded and connected with the first sealing piece for closing the opening.

In this embodiment, the end cover includes end cover body, first connection structure and second connection structure. Wherein the end cap body has an opening for accommodating the electrode terminal; the first connecting structure is positioned at the inner side of the open hole and welded with the electrode terminal, namely, the first connecting structure is adjacent to the open hole; the second connecting structure is connected with the first connecting structure and welded with the first sealing piece for closing the opening. Through setting up first connection structure and second connection structure to make first connection structure and electrode terminal be connected, first connection structure is connected with second connection structure, and second connection structure is connected with first sealing member, can realize that the electric current flows directly from electrode terminal to first sealing member, and then makes the electric current flow direction and the external circuit that first sealing member is connected, can avoid the electric current loss because of passing through the battery case like this, thereby increase the output current of battery, and improve the performance of battery.

In one possible embodiment, the end cap body includes a first step structure disposed at an edge of the opening, the first step structure for embedding the first connection structure.

In this embodiment of the present application, when the edge of the opening hole is provided with the first step structure, and the first connection structure is embedded into the first step structure, the first connection structure may be located on the inner side of the opening hole, so that the first connection structure may be welded to the electrode terminal located in the opening hole. By providing the edge of the opening with the first step structure for embedding the first connection structure, the first connection structure can be connected with the electrode terminal located in the opening, thereby allowing current to flow directly from the electrode terminal to the first connection structure.

In one possible embodiment, the end cap body further includes a second step structure adjacent to an inner side of the opening with respect to the first step structure, the second step structure for overlapping the electrode terminal.

In the embodiment of the application, the electrode terminal is positioned in the opening. The end cover body is also provided with a second step structure, and further, the second step structure is closer to the inner side of the opening than the first step structure, namely, the second step structure is adjacent to the opening. The second step structure is used for overlapping the electrode terminal, and the electrode terminal can be connected with the first connecting structure in the first step structure. Through set up the second step structure that is used for overlap joint electrode terminal in the end cover body to the second step structure is closer to the inboard of trompil for first step structure, can make electrode terminal stably place in the trompil, and stably be connected with first connection structure, thereby realizes the stable flow direction of electric current.

In one possible embodiment, the first connection structure includes a third step structure for avoiding a welded structure of the first connection structure and the electrode terminal.

In this embodiment, the first connection structure located in the first step structure is welded to the electrode terminal overlapped in the second step structure. When the two are welded, there are some welded structures, such as solder marks, resulting in surface irregularities of the first connection structure. If the uneven surface of the first connection structure is directly contacted with other components, normal use of the other components is affected. Through setting up the third step structure in first connection structure, can make other parts dodge first connection structure and electrode terminal's welded structure to guarantee other parts's normal use.

In one possible embodiment, the end cap body, the first connection structure and the second connection structure are all annular.

In this embodiment of the application, through making end cover body, first connection structure and second connection structure all be annular, can make first connection structure and second connection structure reasonable, as far as possible distribute in the end cover to realize the good transmission of electric current.

In one possible embodiment, the first connection structure has a dimension of 0.8-1mm in a first direction, the first direction being parallel to the axis of the end cap.

In this embodiment, the first connection structure is not only to be connected to the second connection structure, but also to be welded to the electrode terminal located in the opening. When the size of the first connection structure in the first direction is too small, the welding of the first connection structure and the electrode terminal may have a problem in that the welding is not firm. By keeping the dimension of the first connection structure in the first direction at 0.8-1mm, the connection between the first connection structure and the electrode terminal can be secured, thereby achieving a stable flow direction of current.

In one possible embodiment, the second connection structure has a dimension of 2-4mm in the first direction.

In this embodiment, the second connection structure is connected not only to the first connection structure, but also to the first seal member closing the opening. When the second connection structure is undersized in the first direction, the welding of the second connection structure to the first seal may have a problem of weak welding. By keeping the dimension of the second connection structure in the first direction between 2 and 4mm, a firm connection between the second connection structure and the first sealing member can be ensured, thereby realizing a stable flow direction of current.

In one possible embodiment, in the first direction, the size of the third step structure is not less than 0.2mm.

In this embodiment of the application, the third step structure is used for dodging the welding structure of first connection structure and electrode terminal to guarantee the normal use of other parts around first connection structure and the electrode terminal. By making the dimension of the third step structure in the first direction not smaller than 0.2mm, it is ensured that other components completely avoid the welded structure of the first connection structure and the electrode terminal, thereby further ensuring that current can flow directly from the electrode terminal to the first sealing member.

In a possible embodiment, the first connection structure has a dimension on one side of the end cap axis of not less than 1mm in a second direction, the second direction being perpendicular to the axis of the end cap.

In the embodiment of the application, in order to ensure firm welding of the first connection structure and the electrode terminal, the first connection structure is required to have a size in the first direction. However, the first connection structure is connected not only to the electrode terminal but also to the second connection structure. If the size of the first connection structure in the second direction is too small, the connection effect with the second connection structure is also poor. By making the dimension of the single-sided first connection structure in the second direction not smaller than 1mm, stable connection of the first connection structure and the second connection structure can be realized, thereby realizing stable output of current.

In one possible embodiment, in the second direction, the dimension of the second connection structure on one side of the end cap axis is not less than 5mm.

In the embodiment of the application, the second connecting structure with the proper size can be perfectly matched with the electrode terminal, the end cover and other parts. By making the dimension of the single-sided second connection structure in the second direction not smaller than 5mm, the normal function of the end cap can be ensured.

In one possible embodiment, the material of the electrode terminal includes copper, and the first metal is nickel-plated or copper.

In this embodiment, when the electrode terminal includes copper and the first metal in the first connection structure is copper or steel nickel plating, the electrode terminal including copper may be directly welded to the first connection structure. The first metal in the first connecting structure is copper or steel nickel plating, and the electrode terminal and the first connecting structure are directly welded to achieve better current transmission, so that current loss is avoided, and current flowing to the outside is increased.

In one possible embodiment, the material of the first seal comprises aluminum and the second metal is aluminum.

In this embodiment, when the first sealing member includes aluminum and the second metal in the second connection structure is aluminum, the first sealing member including aluminum may be directly welded to the second connection structure. The aluminum is low in price and easy to obtain, and the aluminum-containing end cover is connected with the aluminum bus component, so that the battery can be electrically connected with the outside, the cost of the battery can be reduced, and the aluminum-containing end cover is beneficial to being applied to large-scale production; and the second metal in the second connecting structure is aluminum, so that the battery can be well connected with the outside, the loss of current is avoided, and the current flowing to the outside is increased.

In one possible embodiment, the first connection structure and the second connection structure are connected by thermal compounding.

In the embodiment of the application, the end cover structure connected through thermal compounding has smaller internal resistance. That is, when the first connection structure and the second connection structure are connected through thermal recombination, current can be better transferred from the first connection structure to the second connection structure, and larger current transfer between the battery and the outside is realized, thereby improving the battery performance.

In a second aspect, there is provided a battery cell comprising: an electrode assembly; a case having a first opening for accommodating the electrode assembly; the end cap of any one of the above embodiments, having a second opening, the end cap for closing the first opening; and a first seal for closing the second opening.

In one possible embodiment, the first seal has a projection compared to the end cap in a first direction that is parallel to the axis of the end cap.

In this embodiment of the application, the second connection structure is welded with the connecting piece that seals the end cover body trompil. When the two are welded, there are some welded structures, such as solder marks, resulting in surface irregularities of the second connection structure. The first sealing member is also connected with the converging component, and if the surface of the rugged second connecting structure is directly contacted with the converging component, the normal use of the converging component can be influenced. Through set up the bulge on first sealing member, can make the welding structure of converging part or other parts dodge second connection structure and first sealing member to guarantee converging part or other parts's normal use.

In one possible embodiment, in the first direction, the dimension of the protrusion is not less than 0.2mm.

In this embodiment of the application, the bulge that is located on the first sealing member is used for dodging the welded structure of second connection structure and first sealing member to guarantee the normal use of other parts around second connection structure and the first sealing member. By making the dimension of the protruding portion in the first direction not smaller than 0.2mm, it is ensured that other members completely avoid the welding structure of the second connecting structure and the first sealing member, thereby further ensuring that current can flow directly from the electrode terminal to the first sealing member and further to the outside.

In a third aspect, a battery is provided, including a plurality of battery cells in the above embodiments; and the converging component is used for electrically connecting a plurality of the battery cells.

In a fourth aspect, a powered device is provided, including a battery in the foregoing embodiments, where the battery is configured to provide electrical energy.

Drawings

FIG. 1 is a schematic view of a vehicle according to an embodiment of the present application;

fig. 2 is an exploded view of a battery according to an embodiment of the present application;

fig. 3 is an exploded view of a battery cell according to an embodiment of the present application;

Fig. 4 is a schematic structural view of a battery cell according to another embodiment of the present application;

FIG. 5 is an exploded view of an end cap according to one embodiment of the present disclosure;

FIG. 6 is a cross-sectional view of an end cap according to an embodiment of the present application;

FIG. 7 is an enlarged view of a portion of area A of FIG. 6;

FIG. 8 is an enlarged view of a portion of region B of FIG. 7;

in the drawings, the drawings are not drawn to scale.

Reference numerals illustrate:

battery 100, first portion 111, second portion 112, controller 200, motor 300;

the battery pack includes a case 10, a battery cell 20, a first seal member 21, an end cap 22, a negative electrode tab 23, an electrode assembly 24, a case 25, an electrode terminal 26, a positive electrode tab 27, a bottom cap 28, and a second seal member 29;

the end cover body 221, the opening 222, the first connecting structure 223, the second connecting structure 224, the upper plastic 265, the end cover plate 266, the sealing ring 267, the lower plastic 268, the first electrode terminal 261 and the second electrode terminal 262;

a first step structure 2211, a second step structure 2212, a third step structure 2213, a welded structure 2214, a first direction X, a second direction Y.

Detailed Description

With the objects, technical solutions and advantages of the embodiments of the present application made clear, the technical solutions in the embodiments of the present application will be clearly described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.

In the description of the present application, it is to be noted that, unless otherwise indicated, the meaning of "plurality" is two or more; the terms "upper," "lower," "left," "right," "inner," "outer," and the like indicate an orientation or positional relationship merely for convenience of description and to simplify the description, and do not indicate or imply that the devices or elements being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus are not to be construed as limiting the present application. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. The "vertical" is not strictly vertical but is within the allowable error range. "parallel" is not strictly parallel but is within the tolerance of the error.

The directional terms appearing in the following description are all directions shown in the drawings and do not limit the specific structure of the present application. In the description of the present application, it should also be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the terms in the present application can be understood as appropriate by one of ordinary skill in the art.

The term "and/or" in this application is merely an association relation describing an associated object, and indicates that three relations may exist, for example, a and/or B may indicate: there are three cases, a, B, a and B simultaneously. In this application, the character "/" generally indicates that the associated object is an or relationship.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having" and any variations thereof in the description and claims of the present application and in the description of the figures above are intended to cover non-exclusive inclusions.

Reference in the specification 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 such phrases 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. Those of skill in the art will explicitly and implicitly understand that the embodiments described herein may be combined with other embodiments.

The battery in the embodiment of the present application may be a lithium ion battery, a lithium metal battery, a lead-acid battery, a nickel-metal separator battery, a nickel-hydrogen battery, a lithium sulfur battery, a lithium air battery, or a sodium ion battery, which is not particularly limited in the embodiment of the present application.

To meet different power demands, multiple battery cells in a battery may be connected in series, parallel, or a series-parallel connection, where a series-parallel connection refers to a mixture of series and parallel connections. Optionally, a plurality of battery cells may be connected in series, parallel or series-parallel to form a battery module, and then connected in series, parallel or series-parallel to form a battery. That is, a plurality of battery cells may be directly assembled into a battery, or may be assembled into a battery module first, and the battery module may be assembled into a battery. The battery is further arranged in the electric equipment to provide electric energy for the electric equipment.

Currently, the application of power batteries is becoming more and more widespread from the development of market forms. The power battery is not only applied to energy storage power supply systems such as hydraulic power, firepower, wind power and solar power stations, but also widely applied to electric vehicles such as electric bicycles, electric motorcycles, electric automobiles, military equipment, aerospace and the like. With the continuous expansion of the application field of the power battery, the market demand of the power battery is also continuously expanding.

The applicant notes that the conventional cylindrical battery cell generally has only one electrode terminal, and the materials connected to the external module confluence part are nickel-plated and aluminum, respectively, and the module confluence part is mostly made of aluminum bar, nickel sheet or nickel-plated materials. Therefore, when the current is generated in the cylindrical battery cell, the current needs to pass through the housing of the cylindrical battery cell, and the internal resistance of the housing is higher, so that the output current of the cylindrical battery cell becomes smaller, and the performance of the cylindrical battery cell is reduced.

In order to solve the problem that the prior cylindrical battery cannot realize larger output current, thereby causing poor battery performance. The embodiment of the application provides an end cover, can make positive and negative electrode terminal all can be directly with converging the part electricity and be connected in the cylindrical battery that is provided with two electrode terminals to make the electric current directly follow electrode terminal flow direction end cover, again flow to the first sealing member of being connected with the end cover, just so need not pass through the free casing of battery, and then increased the free output current of battery and improved the performance of battery.

It should be noted that the end cap provided in the present application is applicable to a cylindrical battery, and particularly, the 4680 structure of the cylindrical battery, but the present application is not limited thereto.

The battery cell disclosed by the embodiment of the application can be used in electric devices such as vehicles, ships or aircrafts, but is not limited to the electric devices. The power supply system provided with the battery cells, the batteries and the like disclosed by the application can be used for forming the power utilization device, so that the current of the cylindrical battery cells in the power supply system can be increased, and the performance of the cylindrical battery cells can be improved.

The technical solutions described in the embodiments of the present application are applicable to various devices using batteries, for example, mobile phones, portable devices, notebook computers, battery cars, electric toys, electric tools, electric vehicles, ships, spacecraft, and the like, where the electric toys may include fixed or mobile electric toys, for example, game consoles, electric car toys, electric ship toys, electric plane toys, and the like, and the spacecraft may include airplanes, rockets, space planes, spacecraft, and the like.

It should be understood that the technical solutions described in the embodiments of the present application are not limited to the above-described devices, but may be applied to all devices using batteries, but for simplicity of description, the following embodiments are described by taking an electric vehicle as an example.

For example, as shown in fig. 1, a schematic structural diagram of a vehicle 1000 according to some embodiments of the present application is provided. The vehicle 1000 may be a fuel oil vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or a range-extended vehicle. The battery 100 is provided in the interior of the vehicle 1000, and the battery 100 may be provided at the bottom or the head or the tail of the vehicle 1000. The battery 100 may be used for power supply of the vehicle 1000, for example, the battery 100 may be used as an operating power source of the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, the controller 200 being configured to control the battery 100 to power the motor 300, for example, for operating power requirements during start-up, navigation, and travel of the vehicle 1000.

In some embodiments of the present application, battery 100 may not only serve as an operating power source for vehicle 1000, but may also serve as a driving power source for vehicle 1000, instead of or in part instead of fuel oil or natural gas, to provide driving power for vehicle 1000.

For example, as shown in fig. 2, a schematic structure of a battery 100 according to an embodiment of the present application is shown. The battery 100 may include a plurality of battery cells 20. In addition to the battery cells, the battery 100 may further include a case 10 (or a cover), the case 10 having a hollow structure inside, and a plurality of battery cells 20 may be accommodated in the case 10. As shown in fig. 2, the case 10 may include two parts, herein referred to as a first part 111 and a second part 112, respectively, the first part 111 and the second part 112 being snapped together. The shape of the first portion 111 and the second portion 112 may be determined according to the shape of the combination of the plurality of battery cells 20, and each of the first portion 111 and the second portion 112 may have one opening. For example, each of the first portion 111 and the second portion 112 may be a hollow rectangular parallelepiped and each has only one surface as an open surface, the opening of the first portion 111 and the opening of the second portion 112 are disposed opposite to each other, and the first portion 111 and the second portion 112 are fastened to each other to form the case 10 having a closed chamber. The plurality of battery cells 20 are connected in parallel or in series-parallel combination and then placed in a box formed by buckling the first part 111 and the second part 112.

In the battery 100, the plurality of battery cells 20 may be connected in series, parallel or a series-parallel connection, wherein the series-parallel connection refers to that the plurality of battery cells 20 are connected in series or parallel. The plurality of battery cells 20 can be directly connected in series or in parallel or in series-parallel, and then the whole formed by the plurality of battery cells 20 is accommodated in the box body; of course, the battery 100 may also be a battery module formed by connecting a plurality of battery cells 20 in series or parallel or series-parallel connection, and a plurality of battery modules are then connected in series or parallel or series-parallel connection to form a whole and are accommodated in a case. The battery 100 may further include other structures, for example, the battery 100 may further include a bus member (not shown) for making electrical connection between the plurality of battery cells 20.

Wherein each battery cell 20 may be a secondary battery or a primary battery; but not limited to, lithium sulfur batteries, sodium ion batteries, or magnesium ion batteries.

Fig. 3 is an exploded view of a battery cell according to an embodiment of the present application, and fig. 4 is a view illustrating a structure of a battery cell 20 according to another embodiment of the present application. As shown in fig. 3 and 4, the battery cell 20 may include a first seal member 21, an end cap 22, a negative electrode tab 23, an electrode assembly 24, a case 25, a positive electrode tab 27, a bottom cap 28, and a second seal member 29. The case 25 forms an outer case or a battery case with the first seal 21 and the second seal 29, and the wall of the case 25, the wall of the first seal 21 and the wall of the second seal 29 are all referred to as the wall of the battery cell 20. The case 25 is formed according to the combined shape of one or more electrode assemblies 24. The housing 25 is a hollow cylinder, and the end surface of the housing 25 is an opening surface, i.e., the end surface has no wall body so that the inside and the outside of the housing 25 are communicated. As can be seen in fig. 3, the housing 25 of the cylindrical battery cell 20 has two circular end faces with a cylindrical body therebetween, and the cylindrical body portion may include an electrode assembly 24. The end cap 22 and the bottom cap 27 cover the upper and lower openings and are coupled to the case 25, and then a closed cavity in which the electrode assembly 24 is placed is formed by the first and second sealing members 21 and 29. The housing 25 is filled with an electrolyte, such as an electrolytic solution.

The battery cell 20 further includes electrode terminals 26, and the electrode terminals 26 are inserted into the end cap 22 and the bottom cap 28, respectively, to form electrical connection with the first sealing member 21 and the second sealing member 29. More specifically, the electrode terminals 26 include a first electrode terminal 261 and a second electrode terminal 262. The first electrode terminal 261 is disposed opposite to the second electrode terminal 262.

The battery cell 20 may further include a current collecting member for electrically connecting the electrode assembly 24 and the electrode terminal 26.

In addition, each electrode assembly 24 has two tabs, for example, a first tab and a second tab, which are opposite in polarity. For example, when the first tab is a positive tab, the second tab is a negative tab. For another example, the first tab is a copper tab and the second tab is an aluminum tab. The first tab of one or more electrode assemblies 24 is connected to the electrode terminal 26 through one current collecting member, and the second tab of one or more electrode assemblies 24 is connected to the other electrode terminal 26 through the other current collecting member.

In this embodiment, the first tab and the second tab of the battery cell 20 are disposed at two ends, respectively. The first tab described below is a copper tab and the second tab is an aluminum tab unless otherwise specified.

In some embodiments, the battery cell 20 may not be provided with the bottom cover 28, that is, the aluminum tab may be directly connected with the second seal 29.

In the battery cell 20, the electrode assembly 24 may be provided in a single unit, or in a plurality of units, as shown in fig. 4, according to actual use requirements, and one electrode assembly 24 is provided in the battery cell 20.

Fig. 5 is an exploded view of the end cap 22 according to one embodiment of the present application. As shown in fig. 5, the end cap 22 includes: an end cap body 221, the end cap body 221 having an aperture 222; a first connection structure 223 including a first metal, the first connection structure 223 being disposed inside the opening 222 for welding connection with the electrode terminal 26 located inside the opening 222; a second connection structure 224 comprising a second metal, the second connection structure 224 being connected to the first connection structure 223, the second connection structure 224 being adapted for welded connection with the first seal 21 closing the aperture 222.

As shown in fig. 5, the end cap 22 may also include an upper plastic 225, an end cap piece 226, a seal ring 227, and a lower plastic 228.

In the embodiment of the present application, the electrode terminal 26 passes through the opening 222 to be connected with the cap 22. The electrode terminals 26 are members for electrical connection, that is, the current generated by the electrode assembly 24 is transferred to the positive and negative electrodes of the battery cell 20 through the electrode terminals 26.

More specifically, the first electrode terminal 261 is connected with the end cap 22, and the first electrode terminal 261 is electrically connected with the copper tab. That is, the current generated from the electrode assembly 24 is transferred to the end cap 22 through the first electrode terminal 261 at one end, and thus to the first sealing member 21, and transferred to the second sealing member 29 at the second electrode terminal 262 through the second electrode terminal 262 at the other end. The first sealing member 21 and the second sealing member 29 are both connected to the bus member, so that current can flow directly from the electrode assembly 24 to the outside without passing through the case 25 of the battery cell 20.

Here, the first connection structure 223 and the first electrode terminal 261 must be welded. If the first connection structure 223 and the first electrode terminal 261 are connected by other means, the internal resistance between the two is large, which still causes the current loss of the battery cell 20, so the first metal contained in the first connection structure 223 must be a metal that can be welded to the first electrode terminal 261.

In addition, the opening 222 serves to accommodate the first electrode terminal 261, and thus the size of the opening 222 should be set according to the size of the electrode assembly 24 or the first electrode terminal 261, and the specific size of the opening 222 is not limited in this application.

The end cap 22 includes an end cap body 221, a first connection structure 223, and a second connection structure 224. Wherein the end cap body 221 has an opening 222, the opening 222 for accommodating the first electrode terminal 261; the first connection structure 223 is positioned inside the opening 222 and welded to the first electrode terminal 261, i.e., the first connection structure 223 is adjacent to the opening 222; the second connection structure 224 is connected to the first connection structure 223 and is welded to the first seal 21 closing the opening 222. When the first connection structure 223 is connected to the first electrode terminal 261, electrical connection between the first electrode terminal 261 and the first connection structure 223 may be achieved; when the first connection structure 223 is connected with the second connection structure 224, an electrical connection between the first connection structure 223 and the second connection structure 224 may be achieved. When the first sealing member 21 is connected with the second connection structure 224, an electrical connection between the second connection structure 224 and the first sealing member 21 can be achieved.

In the above-mentioned scheme, by providing the first connection structure 223 and the second connection structure 224 and connecting the first connection structure 223 with the first electrode terminal 261, the first connection structure 223 is connected with the second connection structure 224, and the second connection structure 224 is connected with the first sealing member 21, it is possible to achieve direct current flow from the first electrode terminal 261 to the first sealing member 21, and then to make current flow to the bus member connected with the first sealing member 21, so that it is possible to avoid current loss due to passage through the battery case 25, thereby increasing the output current of the battery cell 20, and improving the performance of the battery 100.

Fig. 6 is a cross-sectional view of an end cap 22 according to an embodiment of the present application. Fig. 7 is a partial enlarged view of the area a in fig. 6. In some embodiments, the end cap body 221 includes a first stepped structure 2211 disposed at an edge of the aperture 222, the first stepped structure 2211 for embedding the first connection structure 223.

When the first step structure 2211 is disposed at the edge of the opening 222 and the first connection structure 223 is embedded in the first step structure 2211, it is possible to realize that the first connection structure 223 is located at the inner side of the opening 221, thereby welding the first connection structure 223 with the first electrode terminal 261 located in the opening 221.

It should be noted here that the inside of the opening 222 and the edge of the opening 222 are areas that are not physically separated from the opening 222, i.e., are connected to the opening 222.

In the above-described aspect, by providing the first stepped structure 2211 for embedding the first connection structure 223 at the edge of the opening 222, the first connection structure 223 can be connected to the first electrode terminal 261 located in the opening 222, so that current can directly flow from the first electrode terminal 261 to the first connection structure 223.

In some embodiments, the end cap body 221 further includes a second stepped structure 2212, the second stepped structure 2212 being adjacent to the inside of the opening 222 with respect to the first stepped structure 2211, the second stepped structure 2212 being for overlapping the first electrode terminal 261.

As previously described, the first electrode terminal 261 is located within the opening 222. The end cap body 221 further has a second step structure 2212 disposed therein, and further, the second step structure 2212 is located closer to the inner side of the opening 222 than the first step structure 2211, that is, the second step structure 2212 is also adjacent to the opening 222, so to speak, the second step structure 2212 is connected to the opening 222. The second step structure 2212 is used for overlapping the first electrode terminal 261, and connection of the first electrode terminal 261 with the first connection structure 223 on the first step structure 2211 can be achieved.

In the above-mentioned aspect, by providing the second step structure 2212 for overlapping the first electrode terminal 261 in the end cap body 221, and the second step structure 2212 is closer to the inner side of the opening 222 than the first step structure 2211, the first electrode terminal 261 can be stably placed in the opening 222 and stably connected with the first connection structure 223, thereby achieving a stable flow direction of the current.

In some embodiments, the first connection structure 223 includes a third step structure 2213, and the third step structure 2213 is used to avoid the welding structure 2214 of the first connection structure 223 and the first electrode terminal 261.

The first connection structure 223 located within the first step structure 2211 is welded to the first electrode terminal 261 overlapped in the second step structure 2212. When the two are welded, there are some welding structures 2214, such as welding marks, resulting in surface irregularities of the first connection structure 223. If the surface of the rugged first connection structure 223 is directly brought into contact with other components, normal use of the other components may result.

For example, in some embodiments of the present application, the second connection structure 224 may also be welded to the first seal 21, and the first seal 21 may contact the surface of the first connection structure 223. When the surface of the first connection structure 223 has the rugged welding structure 2214, welding or normal use of the end cap 22 may be affected.

In the above-mentioned aspect, by providing the third step structure 2213 in the first connection structure 223, other components can be avoided from the welding structure 2214 of the first connection structure 223 and the first electrode terminal 261, thereby ensuring normal use of the other components.

In some embodiments, the end cap body 221, the first connection structure 223, and the second connection structure 224 are all annular.

When the electrode assembly 24 generates current, the current is first transferred to the first electrode terminal 261, then transferred to the first connection structure 223 through the first electrode terminal 261, then transferred to the second connection structure 224 through the first connection structure 223, then transferred to the first sealing member 21 through the second connection structure 224, and finally transferred to other components such as an external bus member through the first sealing member 21, thereby forming the plurality of battery cells 20 into a battery module having electrical connection. Therefore, in theory, only the portions to be transferred with current need to be provided as the first connection structure 223 and the second connection structure 224, respectively, but for better transfer of current, both the first connection structure 223 and the second connection structure 224 may be made annular. However, in the practical application process, the producer may set corresponding parts according to the practical production requirement, and the specific positions of the first connection structure 223, the second connection structure 224, and the like in the end cover 22 are not limited in this application.

In the above-mentioned scheme, by making the end cover body 221, the first connection structure 223 and the second connection structure 224 all have the ring shape, the first connection structure 223 and the second connection structure 224 can be reasonably distributed in the end cover 22 as much as possible, thereby realizing good current transmission.

Fig. 8 is a partial enlarged view of the area B in fig. 7. As shown in fig. 7 and 8, in some embodiments, the dimension D1 of the first connection structure 223 is 0.8-1mm in a first direction X that is parallel to the axis of the end cap 22.

The first connection structure 223 is to be connected not only to the second connection structure 224 but also to the first electrode terminal 261 located in the opening 222 by welding. When the dimension D1 of the first connection structure 223 in the first direction X is too small, the welding of the first connection structure 223 and the first electrode terminal 261 may have a problem in that the welding is not firm.

For example, in the embodiment of the present application, the dimension D1 of the first connection structure 223 in the first direction X may be 0.85mm, 0.9mm, 1mm, or the like, so long as engineering requirements are satisfied, and no specific requirement is imposed on the value of D1 in the present application.

In the above-described aspect, by maintaining the dimension D1 of the first connection structure 223 in the first direction X to be 0.8-1mm, the connection between the first connection structure 223 and the first electrode terminal 261 can be secured, thereby achieving a stable flow direction of current.

In some embodiments, the dimension D2 of the second connection structure 224 is 2-4mm in the first direction X.

For example, in the embodiment of the present application, the dimension D2 of the second connection structure 224 in the first direction X may be 2mm, 3mm, 3.5mm, 4mm, or the like, so long as engineering requirements are satisfied, and no specific requirement is imposed on the value of D3 in the present application.

The second connection structure 224 is connected not only to the first connection structure 223 but also to the first seal 21 closing the opening 222. When the dimension D2 of the second connection structure 224 in the first direction X is too small, the welding of the second connection structure 224 and the first seal 21 may have a problem of weak welding.

In the above-described scheme, by keeping the dimension D2 of the second connection structure 224 in the first direction X to be 2-4mm, the connection between the second connection structure 224 and the first sealing member 21 can be ensured to be firm, thereby achieving stable flow direction of current.

In some embodiments, the dimension D3 of the third step structure 2213 is not less than 0.2mm in the first direction X.

For example, in the embodiment of the present application, the dimension D3 of the third step structure 2213 in the first direction X may be 0.2mm, 0.3mm, 0.35mm, or 0.4mm, etc., as long as the engineering requirements are satisfied, and there is no specific requirement on the value of D3 in the present application.

The third step structure 2213 is used to avoid the welding structure 2214 of the first connection structure 223 and the first electrode terminal 261 to ensure normal use of other components around the first connection structure 223 and the first electrode terminal 261.

In the above-described aspect, by making the dimension D3 of the third step structure 2213 in the first direction X not smaller than 0.2mm, it is ensured that other components completely avoid the welding structure 2214 of the first connection structure 223 and the first electrode terminal 261, thereby further ensuring that current can flow directly from the first electrode terminal 261 to the end cap 22.

In some embodiments, the dimension D4 of the first connection structure 223 on one side of the axis of the first seal 21 is not less than 1mm in the second direction Y, which is perpendicular to the axis of the end cap 22.

In order to secure the firm welding of the first connection structure 223 and the first electrode terminal 26126, a dimension D1 of the first connection structure 223 in the first direction X is required. However, the first connection structure 223 is connected not only to the first electrode terminal 261 but also to the second connection structure 224. If the dimension D4 of the first connection structure 223 in the second direction Y is too small, the connection effect with the second connection structure 224 is also poor.

As is apparent from the cross-sectional view of the end cap 22, the end cap body 221, the first connection structure 223, and the second connection structure 224 are all bilaterally symmetrical, and the first connection structures 223 present on both sides are welded to the first electrode terminals 261, respectively. On a single side, therefore, the dimension D4 of the first connection structure 223 in the second direction Y is not less than 1mm.

For example, in the embodiment of the present application, the dimension D4 of the first connection structure 223 on one side in the second direction Y may be 1mm, 1.5mm, 2mm, or the like, so long as engineering requirements are satisfied, and there is no specific requirement on the value of D3 in the present application.

In the above-described aspect, by making the dimension D4 of the one-sided first connection structure 223 in the second direction Y not smaller than 2mm, stable connection of the first connection structure 223 and the second connection structure 224 can be achieved, thereby achieving stable output of current.

In some embodiments, the dimension D5 of the second connecting structure 224 on the axial side of the end cap 22 in the second direction Y is not less than 5mm.

For example, in the embodiment of the present application, the dimension D4 of the second connection structure 224 on one side in the second direction Y may be 2mm, 3mm, 4mm, or the like, so long as engineering requirements are satisfied, and there is no specific requirement on the value of D3 in the present application.

The second connection structure 224 having a proper size may achieve a perfect fit with the first electrode terminal 261, the first sealing member 21, and the like. Also, the second connection structures 224 existing on both sides are respectively welded to the first seals 21, so that the dimension D5 of the second connection structures 224 in the second direction Y is not less than 5mm on one side.

In the above-described aspect, by making the dimension D5 of the single-sided second connection structure 224 in the second direction Y not smaller than 5mm, the normal function of the end cap 22 can be ensured.

In some embodiments, the material of the electrode terminal 26 includes copper, and the first metal is nickel-plated or copper.

As described above, the first connection structure 223 and the first connection terminal 261 must be connected in the form of welding, so the first metal in the first connection structure 223 must be a metal that can be welded with the first electrode terminal 261. When the electrode terminal 26, more particularly, when the material of the first electrode terminal 261 includes copper and the first metal in the first connection structure 223 is nickel-plated with copper or steel, the first electrode terminal 261 containing copper may be directly welded to the first connection structure 223.

In the above-mentioned scheme, the electrode terminal 26 and the first connection structure 223 are directly welded to achieve better current transmission by making the first metal in the first connection structure 223 copper or steel nickel plated, so as to avoid the loss of current, thereby realizing the increase of current flowing to the outside.

In some embodiments, the material of the first seal 21 comprises aluminum and the second metal is aluminum.

When the first seal 21 comprises aluminum and the second metal in the second connection structure 224 is aluminum, the aluminum-containing first seal 21 may be directly welded to the second connection structure 224.

In the present embodiment, the material of the second seal 29 also includes aluminum unless otherwise specified.

In the above scheme, aluminum is low in price and easy to obtain, and by connecting the aluminum-containing first sealing member 21 with the aluminum-containing confluence part, the electric connection between the battery cell 20 and the outside can be realized, the cost of the battery 100 can be reduced, and the aluminum-containing sealing member is beneficial to being applied to large-scale production; and by making the second metal in the second connection structure 224 aluminum, it is possible to achieve good connection of the battery cell 20 with the outside, avoid loss of current, and thus achieve an increase in current flowing to the outside.

In the embodiment of the present application, the material of the first tab in the battery cell 20 is copper, and therefore, the material of the electrode terminal 26 connected to the first tab needs to include copper, that is, the material of the first electrode terminal 261 includes copper. The material of the second tab is aluminum, and thus, the material of the electrode terminal 26 connected to the second tab needs to include aluminum, that is, the material of the second electrode terminal 292 includes aluminum. Referring to fig. 4, the first tab is electrically connected to the first electrode terminal 261, the first electrode terminal 261 is electrically connected to the end cap 22, and the end cap 22 is electrically connected to the external bus member through the first seal 21; the second electrode tab is electrically connected to the second electrode terminal 262, the second electrode terminal 262 is electrically connected to the second seal 29, and the second seal 29 is electrically connected to an external bus member.

In some embodiments, the first connection structure 223 and the second connection structure 224 are connected by thermal compounding.

The thermal compounding is herein referred to as hot rolling. The hot rolling is rolling performed at a temperature equal to or higher than the crystallization temperature. The metal has high plasticity and low deformation resistance during hot rolling, and the energy consumption of metal deformation can be greatly reduced. The processing performance of metals and alloys can be improved by hot rolling, namely, coarse grains in a casting state are crushed, crack healing is promoted, casting defects are reduced or eliminated, an as-cast structure is changed into a deformed structure, and the processing performance of the alloy is improved. In the examples herein, copper and aluminum are bonded together at their respective crystallization temperatures.

In the above-described arrangement, the end cap 22 structure that is connected by thermal compounding has a small internal resistance. That is, when the first connection structure 223 and the second connection structure 224 are connected by thermal recombination, current can be better transferred from the first connection structure 223 to the second connection structure 224, enabling a larger current transfer between the battery cell 20 and the outside, thereby improving the performance of the battery 100.

The embodiment of the application also provides a battery cell 20, and the battery cell 20 includes: an electrode assembly 24; a case 25 having a first opening for accommodating the electrode assembly 24; the end cap 22 in the foregoing embodiments has a second opening, and the end cap 22 is configured to close the first opening; and a first seal 21 for closing the second opening.

As shown in fig. 7, in some embodiments, the first seal 21 has a protrusion 211 as compared to the end cap 22 in a first direction X that is parallel to the axis of the end cap 22.

The second connecting structure 224 is welded to the first seal member 21 closing the opening 222 of the end cap body 221. When the two are welded, there may be some weld 2214, such as a weld mark, resulting in a surface roughness of the second connection structure 224. The first sealing member 21 is also connected to the bus member, and if the surface of the rugged second connection structure 224 is directly contacted to the bus member, normal use of the bus member is affected.

In the above-mentioned scheme, by providing the protruding portion 211 on the first sealing member 21, the converging component or other components can avoid the welding structure 2214 between the second connecting structure 224 and the first sealing member 21, so as to ensure the normal use of the converging component or other components.

In some embodiments, the dimension D6 of the protrusion 211 in the first direction X is not less than 0.2mm.

The protrusion 211 on the first sealing member 21 serves to avoid the second connection structure 224 and the welding structure 2214 of the first sealing member 21 to ensure the normal use of the second connection structure 224 and other components around the first sealing member 21.

In the embodiment of the present application, the dimension of the protruding portion 211 in the first direction X may be 0.2mm, 0.25mm or 0.3mm, which is not required in the present application as long as the engineering requirement is satisfied.

In the above-described aspect, by making the dimension D6 of the protruding portion 211 in the first direction X not smaller than 0.2mm, it is ensured that other components completely avoid the welding structure 2214 of the second connection structure 224 and the first sealing member 21, thereby further ensuring that current can flow directly from the electrode terminal 26 to the first sealing member 21 and further to the outside.

Here, it should be noted that the battery cell 20 provided in the embodiment of the present application has two kinds of electrode terminals 26, a first electrode terminal 261 containing copper and a second electrode terminal 262 containing aluminum, respectively, and the two kinds of electrode terminals 26 are disposed at both ends of the battery cell 20, respectively. That is, the first electrode terminal 261 is connected to the copper tab, and the second electrode terminal 262 is connected to the aluminum tab. The first electrode terminal 261 is connected to the end cap 22, and then to the external bus member through the first seal 21, and the second electrode terminal 262 is connected to the bottom cap 28, and then to the external bus member through the second seal 29.

The embodiment also provides a battery 100, which comprises the battery cell 20 in the previous embodiment.

Embodiments of the present application also provide a powered device, where the powered device may include the battery 100 in the foregoing embodiments, to provide power for the powered device. Alternatively, the powered device may be a vehicle, a ship, or a spacecraft.

In the battery cell 20, a first electrode terminal 261 and a second electrode terminal 262 are oppositely disposed at both ends of the battery cell 20. On the other hand, the first electrode terminal 261 connected to the first tab (i.e., copper tab) is connected to the first sealing member 21 after being connected to the cap 22 including the first connection structure 223 and the second connection structure 224; on the other hand, by connecting the second electrode terminal 262 connected to the second tab (i.e., the aluminum tab) to the second sealing member 29, it is possible to directly transfer the current generated from the electrode assembly 24 to the outside, to avoid the loss of current due to the passage through the case 25, thereby increasing the output current of the battery cell 20 and improving the performance of the battery 100.

While the present application has been described with reference to a preferred embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the present application. In particular, the technical features mentioned in the respective embodiments may be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions falling within the scope of the claims.

Claims (18)

1. An end cap, comprising:

the end cover comprises an end cover body, a cover body and a cover body, wherein the end cover body is provided with an opening;

a first connection structure including a first metal, the first connection structure being disposed inside the opening for welding connection with an electrode terminal located inside the opening;

and the second connecting structure comprises second metal, is connected with the first connecting structure and is used for being welded and connected with the first sealing piece for closing the opening.

2. The end cap of claim 1, wherein the end cap body includes a first step structure disposed at an edge of the aperture, the first step structure for embedding the first connection structure.

3. The end cap of claim 2, wherein the end cap body further comprises a second step structure adjacent to an inner side of the aperture relative to the first step structure, the second step structure for overlapping the electrode terminal.

4. The end cap of any one of claims 1 to 3, wherein the first connection structure includes a third step structure for avoiding a welded structure of the first connection structure and the electrode terminal.

5. The end cap of any one of claims 1 to 3, wherein the end cap body, the first connection structure, and the second connection structure are each annular.

6. A cap according to any one of claims 1 to 3, wherein the first connection feature is 0.8-1mm in size in a first direction, the first direction being parallel to the axis of the cap.

7. The end cap of claim 6, wherein the second connecting structure has a dimension of 2-4mm in the first direction.

8. The end cap of claim 4, wherein the third step feature is no less than 0.2mm in size in a first direction, the first direction being parallel to an axis of the end cap.

9. A cap according to any one of claims 1 to 3, wherein the first connection structure has a dimension on one side of the cap axis of no less than 1mm in a second direction, the second direction being perpendicular to the axis of the cap.

10. The end cap of claim 9, wherein the dimension of the second connection structure on the end cap axis side in the second direction is no less than 5mm.

11. The end cap of any one of claims 1 to 3, wherein the material of the electrode terminal comprises copper and the first metal is nickel-plated or copper-plated.

12. The end cap of any one of claims 1 to 3, wherein the material of the first seal member comprises aluminum and the second metal is aluminum.

13. The end cap of any one of claims 1 to 3, wherein the first connection structure and the second connection structure are connected by thermal compounding.

14. A battery cell, comprising:

an electrode assembly;

a case having a first opening for accommodating the electrode assembly;

the end cap of any one of claims 1 to 13 having a second opening for closing the first opening; and

a first seal for closing the second opening.

15. The battery cell of claim 14, wherein the first seal has a protrusion compared to the end cap in a first direction that is parallel to an axis of the end cap.

16. The battery cell of claim 15, wherein the projection has a dimension of not less than 0.2mm in the first direction.

17. A battery, comprising:

a plurality of the battery cells of any one of claims 14 to 16;

and the converging component is used for electrically connecting a plurality of the battery cells.

18. A powered device, comprising:

the battery of claim 17, said battery for providing electrical energy.

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