CN220963700U - Battery monomer, battery and power consumption device - Google Patents

Abstract

The application is suitable for the technical field of batteries, and provides a battery cell, a battery and an electric device. The housing has an accommodation space and an opening. The electrode assembly is disposed in the receiving space. The cover plate is used for closing the opening, the cover plate is provided with a liquid injection channel, the side wall of the liquid injection channel extends from the outer side of the cover plate to the inner side of the cover plate, and the extending tail end of the liquid injection channel is provided with a tail end corner part. The sealant nails are arranged in the liquid injection channels and are used for sealing the liquid injection channels. The circumferential surface of the sealant nail is matched with the side wall of the liquid injection channel to form a sealing interface, and the sealing interface does not exceed the corner part of the tail end in the direction from the outer side to the inner side of the cover plate. The sealing glue nail is guaranteed to have stronger sealing performance, meanwhile, the possibility that the sealing glue nail is extruded by the tail end corner can be reduced, and the possibility that the sealing glue nail loses sealing performance due to extrusion cracking is reduced.

Description

Battery monomer, battery and power consumption device

Technical Field

The application relates to the technical field of battery production, in particular to a battery monomer, a battery and an electric device.

Background

The cover plate structure is one of the important components of the battery, and is generally provided with a liquid injection hole for injecting electrolyte. In order to ensure the sealing of the liquid injection hole, a sealant nail is required to be inserted into the liquid injection hole.

In the related art, the sealant nail is prone to cracking, thereby losing tightness.

Disclosure of utility model

In order to solve the technical problems, the application provides a battery cell, a battery and an electric device, so as to reduce the possibility of cracking of sealant nails in the battery cell.

In a first aspect, an embodiment of the present application provides a battery cell, including:

A housing having an accommodation space, the housing having an opening;

An electrode assembly disposed in the receiving space;

A cover plate for closing the opening, the cover plate having a liquid injection passage, a side wall of the liquid injection passage extending from an outer side of the cover plate to an inner side of the cover plate, and an extending end thereof having an end corner portion;

The sealant nail is arranged in the liquid injection channel and is used for sealing the liquid injection channel; the circumferential surface of the sealant nail is matched with the side wall of the liquid injection channel to form a sealing interface, and the sealing interface does not exceed the tail end corner part from the outer side to the inner side of the cover plate.

In the technical scheme, when guaranteeing that the sealant nail has stronger sealing performance, the possibility that the sealant nail is extruded by the tail end corner can be reduced, the possibility that the sealant nail loses sealing performance due to extrusion cracking is reduced, and then the use safety of the battery cell is improved.

In some embodiments, the length of the sealant peg is no greater than the length of the injection channel.

In the technical scheme, the sealant nails are positioned in the liquid injection channels, so that the liquid injection channels are convenient for protecting the sealant nails.

In some embodiments, the sealant nail comprises a sealing section and a clearance fit section along the length direction, the clearance fit section is connected to one end of the sealing section close to the electrode assembly, the circumferential surface of the sealing section is in interference fit with the side wall of the liquid injection channel and forms the sealing interface, and the clearance fit section extends towards the side close to the electrode assembly and is in clearance fit with the side wall of the liquid injection channel.

In the technical scheme, when the sealant nails enter the liquid injection channel, the clearance fit section enters before the sealing section, so that the installation of the sealant nails is facilitated.

In some embodiments, the circumferential surface of the sealant nail at any position along the length direction thereof is in interference fit with the side wall of the liquid injection channel and forms the sealing interface.

In the technical scheme, the area of a sealing interface formed by interference fit between the circumferential surface of the sealing glue nail and the side wall of the liquid injection channel is large, and the sealing performance of the sealing glue nail is improved.

In some embodiments, the liquid injection channel includes a first section and a second section along a length direction, the second section is located on a side of the first section, where the first section is close to the electrode assembly, a cross-sectional area of the second section is smaller than a cross-sectional area of the first section, a step is formed at an intersection of the first section and the second section, the sealant nail is located in the first section, and a cross-sectional area of the sealant nail is larger than a cross-sectional area of the second section.

In the technical scheme, the second section of the liquid injection channel can limit the sealant nails, so that the possibility that the sealant nails fall into the accommodating space is reduced.

In some embodiments, the cover plate comprises a plate body and a cylinder body, wherein the plate body is provided with an orifice, the cylinder body is arranged on one side, close to the accommodating space, of the plate body, the cylinder body surrounds the orifice, and the wall of the orifice and the inner wall of the cylinder body surround to form the liquid injection channel.

In the technical scheme, the cylinder facilitates the formation of the liquid injection channel.

In some embodiments, an end surface of the sealant nail at an end remote from the accommodation space is flush with an outer surface of the cover plate.

In the technical scheme, after the sealant nails enter the liquid injection channel, the installation state of the sealant nails can be judged through the level of the end faces of the sealant nails and the cover plate, and the assembly of the sealant nails is convenient.

In some embodiments, the cover plate is a unitary structure.

In the technical scheme, through the structural form of apron, can improve the structural strength of apron, promote the intensity of annotating the liquid passageway simultaneously.

In a second aspect, an embodiment of the present application provides a battery, including a battery cell according to any embodiment of the present application.

In the technical scheme, through adopting the battery monomer related to above, the possibility that the sealant nail is extruded and cracked can be reduced, the use safety of the battery monomer is improved, and then the safety performance of the battery can be improved.

In a third aspect, an embodiment of the present application provides an electrical apparatus, including a battery cell according to any embodiment of the present application or a battery according to any embodiment of the present application.

In the technical scheme, through adopting the battery monomer or the battery related to above, the possibility that the sealant nails are extruded and cracked can be reduced, the use safety of the battery monomer is improved, and then the safety performance of the battery can be improved, so that the electric device has higher reliability.

The foregoing description is only an overview of the present application, and is intended to provide a better understanding of the technical means of the present application, as it is embodied in the present specification, and is intended to provide a better understanding of the above and other objects, features and advantages of the present application, as it is embodied in the following description.

Drawings

Fig. 1 is a schematic cross-sectional view of a cap plate of a battery cell according to a first embodiment of the present application;

fig. 2 is a schematic cross-sectional view of a cap plate of a battery cell according to a second embodiment of the present application;

Fig. 3 is a schematic cross-sectional view of a cover plate of a battery cell according to a third embodiment of the present application.

Description of the reference numerals

1. A cover plate; 1a, a liquid injection channel; 1aa, terminal corner portion; 1a1, a first section; 1a2, a second section; 1a3, a step portion; 11. a plate body; 11a, an orifice; 12. a cylinder; 2. sealing glue nails; 2a, sealing interface; 21. a sealing section; 22. and a clearance fit section.

Detailed Description

The present application will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present application more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application.

The individual features described in the specific embodiments can be combined in any suitable manner, without contradiction, for example by combination of different specific features, to form different embodiments and solutions. Various combinations of the specific features of the application are not described in detail in order to avoid unnecessary repetition.

In the following description, references to the term "first\second\ …" are merely to distinguish between different objects and do not indicate that the objects have the same or a relationship. It should be understood that references to orientations of "above", "below", "outside" and "inside" are all orientations in normal use, and "left" and "right" directions refer to left and right directions illustrated in the specific corresponding schematic drawings, and may or may not be left and right directions in normal use.

It should be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element. "at least two" means greater than or equal to two.

Currently, the more widely the battery is used in view of the development of market situation. The 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 vehicles and the like, and the fields of aerospace and the like. With the continuous expansion of the battery application field, the market demand and the yield of the battery are also continuously expanding.

In the production process of the battery, electrolyte is required to be injected into the shell along the liquid injection hole, and the liquid injection hole is sealed by using a sealant nail. In the related art, the sealant nail is prone to cracking, thereby losing tightness.

The applicant researches and discovers that in the related art, when the sealant nail seals the liquid injection hole, the sealant nail extends into the shell, so that the sealant nail is easy to contact with the corner of the liquid injection hole, the sealant nail is easy to swell after being contacted with electrolyte, the cross section area of the sealant nail is increased, the corner of the liquid injection hole can squeeze the sealant nail, the sealant nail generates concentrated stress at the corner of the liquid injection hole, and the sealant nail is easy to crack under the action of the concentrated stress, so that the tightness of the sealant nail is influenced.

Based on the above considerations, in order to solve the problem that the sealant nail of the battery is easily cracked, the applicant has conducted intensive studies to design a battery cell including a case, an electrode assembly, a cap plate, and a sealant nail.

The housing has an accommodation space and an opening. The electrode assembly is disposed in the receiving space. The cover plate is used for closing the opening, the cover plate is provided with a liquid injection channel, the side wall of the liquid injection channel extends from the outer side of the cover plate to the inner side of the cover plate, and the extending tail end of the liquid injection channel is provided with a tail end corner part. The sealant nails are arranged in the liquid injection channels and are used for sealing the liquid injection channels. The circumferential surface of the sealant nail is matched with the side wall of the liquid injection channel to form a sealing interface, and the sealing interface does not exceed the corner part of the tail end in the direction from the outer side to the inner side of the cover plate. Therefore, when the sealant nail is guaranteed to have strong sealing performance, the possibility that the sealant nail is extruded by the tail end corner can be reduced, the possibility that the sealant nail loses sealing performance due to extrusion cracking is reduced, and the use safety of the battery cell is further improved.

The embodiment of the application provides a battery, which comprises a battery monomer. A battery is a single physical module that includes one or at least two battery cells to provide higher voltage and capacity. When at least two battery monomers are provided, the at least two battery monomers are connected in series, in parallel or in series-parallel through the converging component. The series-parallel connection refers to that at least two battery monomers are connected in series or in parallel.

In some embodiments, the battery may be a battery module. When at least two battery cells are arranged, the at least two battery cells are arranged and fixed to form a battery module. As one example, at least two battery cells may be fixed by a tie or the like to form a battery module. As one example, at least two battery cells may also be fixed by end plates, side plates, etc. to form a battery module.

In other embodiments, the battery may be a battery pack, which may include a case and a battery cell. As one example, the battery cells may be directly accommodated in the case. As an example, the battery cells may be formed into a battery module first and then accommodated in a case.

The battery cell according to the embodiment of the application refers to the minimum unit for storing and outputting electric energy. The battery cell can be a secondary battery or a primary battery.

The embodiment of the application provides an electric device which comprises the battery monomer or the battery. The battery cell or battery may provide electrical energy to the powered device. The electric device can be, but is not limited to, a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, a battery car, an electric automobile, a ship, a spacecraft and the like. Among them, the electric toy may include fixed or mobile electric toys, such as game machines, electric car toys, electric ship toys, electric plane toys, and the like, and the spacecraft may include planes, rockets, space planes, and spacecraft, and the like.

In the following embodiments, for convenience of explanation, an electric device vehicle according to an embodiment of the present application will be described as an example.

The vehicle can be a fuel oil vehicle, a fuel gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle or a range-extended vehicle and the like. The interior of the vehicle is provided with a battery, which may be provided at the bottom or at the head or at the tail of the vehicle. The battery may be used for power supply of the vehicle, for example, the battery may be used as an operating power source of the vehicle. The vehicle may also include a controller and a motor, the controller being configured to control the battery to power the motor, for example, for operating power requirements during start-up, navigation, and travel of the vehicle.

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

Referring to fig. 1, a battery cell according to an embodiment of the present application includes a case (not shown), an electrode assembly (not shown), a cap plate 1, and a sealant nail 2. The housing has an accommodation space (not shown in the drawings) and has an opening. The electrode assembly is disposed in the receiving space. The cap plate 1 is used for closing the opening, the cap plate 1 has a liquid filling channel 1a, a side wall of the liquid filling channel 1a extends from an outer side of the cap plate 1 to an inner side of the cap plate 1, and an extending end thereof has a terminal corner portion 1aa. The sealant nail 2 is arranged in the liquid injection channel 1a and is used for sealing the liquid injection channel 1a. The circumferential surface of the sealant nail 2 cooperates with the side wall of the liquid injection passage 1a to form a sealing interface 2a, and the sealing interface 2a does not exceed the terminal corner portion 1aa in the direction from the outside to the inside of the cover plate 1.

The shell is used as an appearance structural member of the battery unit. The shape of the housing is not limited.

The electrode assembly is a component in which electrochemical reactions occur in the battery cells. One or more at least two electrode assemblies may be contained within the case. The electrode assembly is mainly formed by winding a positive electrode sheet (positive electrode sheet and negative electrode sheet), and a separator is generally provided between the positive electrode sheet and the negative electrode sheet. The portions of the electrode sheets (positive electrode sheet and negative electrode sheet) having the active material constitute the main body portion of the electrode assembly, and the main body portion is connected to the tab. The positive electrode tab and the negative electrode tab may be located at one end of the main body portion together or located at two ends of the main body portion respectively. In the charge and discharge process of the battery, the positive electrode active material and the negative electrode active material react with the electrolyte, and the lugs are connected with the poles to form a current loop.

The number of the electrode assemblies may be one or at least two in the battery cell.

In some instances, the electrode assembly may also be referred to as a bare cell, a jelly roll, or the like.

The cap plate 1 refers to a member that is covered on the opening of the case to isolate the inner environment of the battery cell from the outer environment. The shape of the cover plate 1 may be adapted to the shape of the opening of the housing. The cover plate 1 can be made of a material (such as aluminum alloy) with certain hardness and strength, so that the cover plate 1 is not easy to deform when being extruded and collided, the battery unit can have higher structural strength, and the safety performance can be improved.

The material of the cover plate 1 may be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not particularly limited in the embodiment of the present application.

The outside of the cover plate 1 refers to a side of the cover plate 1 away from the accommodation space of the housing. The inner side of the cover plate 1 means a side of the cover plate 1 close to the receiving space of the housing. It will be appreciated that electrolyte can flow into the receiving space along the pouring channel 1 a.

The extension end of the side wall of the injection channel 1a having the distal corner portion 1aa means the distal corner portion 1aa formed by the change of the extension direction of the side wall of the injection channel 1a when it extends to the end close to the electrode assembly. It is understood that when the electrolyte flows toward the accommodating space along the side wall of the pouring channel 1a, the electrolyte flows through the terminal corner portion 1aa and then enters the accommodating space.

The sealing interface 2a refers to an interface formed by interference fit of the circumferential surface of the sealant nail 2 with the side wall of the liquid injection channel 1a, which blocks the electrolyte from flowing out of the accommodating space.

In the battery cell according to the embodiment of the application, after the sealant nail 2 is inserted into the liquid injection channel 1a, the sealing interface 2a is positioned at one side of the terminal corner part 1aa away from the accommodating space. That is, the portion of the sealant nail 2 for sealing is not in contact with the distal corner portion 1 aa. Therefore, the possibility that the sealant nail 2 is pressed by the end corner portion 1aa due to swelling or the like can be reduced, the possibility that the sealant nail 2 loses sealability due to pressing cracking is reduced, and further the use safety of the battery cell is improved.

The specific length of the sealant nail 2 is not limited so that the sealing interface 2a formed between the sealant nail 2 and the liquid injection passage 1a does not exceed the terminal corner portion 1aa in the direction from the outside to the inside of the cap plate 1.

In some embodiments, referring to fig. 2, the length of the sealant nail 2 is not greater than the length of the liquid injection channel 1 a. In this way, the sealant nail 2 is located inside the liquid injection channel 1a, so that the liquid injection channel 1a can fully protect the sealant nail 2, and the possibility that the sealant nail 2 is damaged in the moving and conveying process of the battery cell is reduced.

The specific shape of the sealant nail 2 is not limited.

In some embodiments, referring to fig. 2, the sealant nail 2 includes a sealing section 21 and a clearance fit section 22 along a length direction, the clearance fit section 22 is connected to one end of the sealing section 21 near the electrode assembly, a circumferential surface of the sealing section 21 is in interference fit with a side wall of the liquid injection channel 1a to form a sealing interface 2a, and the clearance fit section 22 extends to a side near the electrode assembly and is in clearance fit with the side wall of the liquid injection channel 1 a.

The clearance fit means that there is a gap between the circumferential surface of the clearance fit section 22 and the side wall of the pouring channel 1 a. That is, the cross-sectional area of the seal segment 21 is greater than the cross-sectional area of the clearance fit segment 22.

It will be appreciated that when the sealant nail 2 is inserted into the liquid injection channel 1a, the clearance fit section 22 is advanced before the seal section 21, and the cross-sectional area of the clearance fit section 22 is smaller than that of the seal section 21, so that when the clearance fit section 22 is inserted into the liquid injection channel 1a, a gap is formed between the circumferential surface of the clearance fit section 22 and the side wall of the liquid injection channel 1a, so that the friction force applied to the sealant nail 2 can be reduced, the sealant nail 2 can easily enter the liquid injection channel 1a, the installation of the sealant nail 2 is facilitated, and meanwhile, an installer does not need to accurately align the clearance fit section 22 with the liquid injection channel 1a when inserting the sealant nail 2, and the assembly process of the sealant nail 2 can be simplified.

The cross-sectional area of the sealant nail 2 refers to an area on a section perpendicular to the longitudinal direction of the sealant nail 2. The cross-sectional area of the sealant nail 2 can be measured as follows: pulling out the sealant nail 2 from the liquid injection channel 1a, wherein in the embodiment that the cross section shape of the sealant nail 2 is circular, the outer diameter of the sealant nail 2 can be measured through a vernier caliper, and the cross section area is calculated through the outer diameter; of course, if the cross-sectional shape of the sealant nail 2 is circular or non-circular, the sealant nail 2 may be cut perpendicular to the length direction thereof, and the area of the cross-section may be measured.

Illustratively, the clearance fit section 22 is frustoconical in shape.

Illustratively, the side generatrix of the clearance fit section 22 is arcuate with the concave side of the arc facing away from the pouring channel 1a. In this way, the clearance fit section 22 is facilitated to smoothly enter the pouring channel 1a.

Illustratively, the end face of the clearance fit section 22 proximate to one end of the electrode assembly may be planar or curved.

It should be noted that the specific ratio of the length of the sealing section 21 to the length of the sealant nail 2 is not limited, and may be 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8 or 0.9, so that the circumferential surface of the sealant nail 2 can cooperate with the side wall of the liquid injection channel 1a to form the sealing interface 2 a.

The shape of the seal segment 21 is not limited, for example, in some embodiments, the seal segment 21 is in the shape of an equal diameter cylinder. In other embodiments, referring to fig. 3, the cross-sectional area of the sealant nail 2 may be gradually reduced from the outside to the inside of the cover plate 1, and the cross-sectional area of the sealing section 21 is also gradually reduced, so that the elastic deformation degrees of the sealing section 21 at different length positions are different.

In some embodiments, referring to fig. 1, the circumferential surface of the sealant nail 2 at any position along the length direction thereof is in interference fit with the side wall of the liquid injection channel 1a and forms a sealing interface 2a. That is, the sealant nail 2 has an equal diameter cylindrical shape. In this way, the area of the sealing interface 2a formed by the sealant nail 2 is made large, and the sealing property of the sealant nail 2 to the liquid injection passage 1a can be enhanced.

In some embodiments, referring to fig. 1, the cover 1 includes a plate 11 and a cylinder 12, the plate 11 has an orifice 11a, the cylinder 12 is disposed on a side of the plate 11 near the accommodating space, the cylinder 12 surrounds the orifice 11a, and a wall of the orifice 11a and an inner wall of the cylinder 12 enclose to form the liquid injection channel 1a. In this way, the length of the liquid injection passage 1a can be increased by extending the length of the cylinder 12, and the thickness required for the plate 11 can be reduced, thereby reducing the material consumption of the cover plate 1 and reducing the production cost.

In some embodiments, referring to fig. 1, an end surface of the sealant nail 2 at an end far away from the accommodating space is flush with an outer surface of the cover plate 1. It can be understood that after the sealant nail 2 enters the liquid injection channel 1a, the installation state of the sealant nail 2 can be judged by the level of the end face of the sealant nail 2 and the cover plate 1, so that an installer can conveniently determine whether the sealant nail 2 is assembled in place or not, and the assembly efficiency is improved.

In some embodiments, referring to fig. 3, the liquid injection channel 1a includes a first section 1a1 and a second section 1a2 along a length direction, the second section 1a2 is located on a side of the first section 1a1 near the electrode assembly, a cross-sectional area of the second section 1a2 is smaller than that of the first section 1a1, a step 1a3 is formed at an intersection of the first section 1a1 and the second section 1a2, the sealant 2 is located in the first section 1a1, and a cross-sectional area of the sealant 2 is larger than that of the second section 1a 2.

It can be understood that the sealant nail 2 can not enter the second section 1a2 of the liquid injection channel 1a, the second section 1a2 of the liquid injection channel 1a can limit the sealant nail 2, and under the condition that the sealant nail 2 breaks and falls off, the second section 1a2 of the liquid injection channel 1a can prevent the sealant nail 2 from falling into the accommodating space, which is beneficial to ensuring the normal use of the electrode assembly, thereby improving the use safety of the battery monomers.

In some embodiments, referring to fig. 1, the cover plate 1 is a unitary structure. In this way, the strength of the pouring channel 1a can be improved while the structural strength of the cover plate 1 can be improved.

In this embodiment, the liquid injection channel 1a of the cover plate 1 may be manufactured by stamping, so that the material consumption of the cover plate 1 can be reduced on the basis of ensuring the structural strength of the liquid injection channel 1a, and meanwhile, the production and the manufacturing of the cover plate 1 are facilitated.

In the description of the present application, a description of the terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the embodiments of the present application. In the present application, the schematic representations of the above terms are not necessarily for the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any or at least two embodiments or examples. Furthermore, the various embodiments or examples described in the present application and the features of the various embodiments or examples may be combined by those skilled in the art without contradiction.

The above description is only of the preferred embodiments of the present application and is not intended to limit the present application, but various modifications and variations can be made by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims (10)

1. A battery cell, comprising:

A housing having an accommodation space, the housing having an opening;

An electrode assembly disposed in the receiving space;

A cover plate for closing the opening, the cover plate having a liquid injection passage, a side wall of the liquid injection passage extending from an outer side of the cover plate to an inner side of the cover plate, and an extending end thereof having an end corner portion;

The sealant nail is arranged in the liquid injection channel and is used for sealing the liquid injection channel; the circumferential surface of the sealant nail is matched with the side wall of the liquid injection channel to form a sealing interface, and the sealing interface does not exceed the tail end corner part from the outer side to the inner side of the cover plate.

2. The battery cell of claim 1, wherein the sealant nail has a length that is no greater than a length of the fluid injection channel.

3. The battery cell according to claim 1 or 2, wherein the sealant nail comprises a sealing section and a clearance fit section along a length direction, the clearance fit section is connected to one end of the sealing section close to the electrode assembly, a circumferential surface of the sealing section is in interference fit with a side wall of the liquid injection channel and forms the sealing interface, and the clearance fit section extends to a side close to the electrode assembly and is in clearance fit with the side wall of the liquid injection channel.

4. The battery cell according to claim 1 or 2, wherein a circumferential surface of the sealant nail at any position in a length direction thereof is interference fit with a side wall of the liquid injection channel and forms the sealing interface.

5. The battery cell according to claim 1, wherein the liquid injection channel comprises a first section and a second section along a length direction, the second section is positioned on one side of the first section close to the electrode assembly, the cross-sectional area of the second section is smaller than that of the first section, a step is formed at the intersection of the first section and the second section, the sealant nail is positioned in the first section, and the cross-sectional area of the sealant nail is larger than that of the second section.

6. The battery cell according to claim 1, wherein the cover plate comprises a plate body and a cylinder body, the plate body is provided with an orifice, the cylinder body is arranged on one side of the plate body, which is close to the accommodating space, the cylinder body surrounds the orifice, and the orifice wall and the inner wall of the cylinder body surround to form the liquid injection channel.

7. The battery cell of claim 1, wherein an end surface of the end of the sealant nail remote from the receiving space is flush with an outer surface of the cover plate.

8. The battery cell of claim 1, wherein the cover plate is of unitary construction.

9. A battery comprising a cell according to any one of claims 1-8.

10. An electrical device comprising a cell according to any one of claims 1 to 8 or a battery according to claim 9.