CN117438714A

CN117438714A - End cover assembly, battery cell, battery and power utilization device

Info

Publication number: CN117438714A
Application number: CN202210832402.2A
Authority: CN
Inventors: 蒲涛; 李志凌; 余文杰
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2022-07-15
Filing date: 2022-07-15
Publication date: 2024-01-23

Abstract

The application provides an end cover assembly, battery cell, battery and power consumption device, end cover assembly includes end cover, insulating part and sealing member. The end cover is provided with a liquid injection hole; the insulating piece is connected to one side of the end cover in the thickness direction, the insulating piece is provided with a concave part communicated with the liquid injection hole, and the concave part is provided with a communication hole communicated with the shell; the sealing component is at least partially arranged in the concave part, can be switched between an initial state and a deformation state, is used for sealing the liquid injection hole and enabling the liquid injection hole to be disconnected from the concave part in the initial state, and is deformed and enables the liquid injection hole to be communicated with the concave part in the deformation state. According to the embodiment of the application, the sealing performance can be improved on the basis of meeting the requirement of liquid injection of the battery monomer, so that the safety performance of the battery monomer is guaranteed.

Description

End cover assembly, battery cell, battery and power utilization device

Technical Field

The application relates to the field of batteries, in particular to an end cover assembly, a battery cell, a battery and an electric device.

Background

Energy conservation and emission reduction are key to sustainable development of the automobile industry, and electric vehicles become an important component of sustainable development of the automobile industry due to the energy conservation and environmental protection advantages of the electric vehicles. For electric vehicles, battery technology is an important factor in the development of the electric vehicles.

In the existing battery manufacturing process, the holes in the end cap assembly for injecting the electrolyte into the battery cells are generally insufficient due to the sealing property, so that the battery cells are contaminated, thereby affecting the safety performance of the battery. Therefore, how to improve the sealing performance of the end cap assembly has become a problem to be solved.

Disclosure of Invention

In view of the above problems, the application provides an end cover assembly, a battery cell, a battery and an electric device, wherein the end cover assembly can improve sealing performance on the basis of meeting the requirement of liquid injection of the battery cell, thereby ensuring the safety performance of the battery cell.

In a first aspect, the present application provides an end cap assembly comprising: the end cover is provided with a liquid injection hole; the insulating piece is connected to one side of the end cover in the thickness direction, the insulating piece is provided with a concave part communicated with the liquid injection hole, and the concave part is provided with a communication hole communicated with the shell; the sealing component is at least partially arranged in the concave part, can be switched between an initial state and a deformation state, is used for sealing the liquid injection hole and enabling the liquid injection hole to be disconnected from the concave part in the initial state, and is deformed and enables the liquid injection hole to be communicated with the concave part in the deformation state.

In the technical scheme of this application embodiment, the end cover has annotates the liquid hole, and the concave part on the insulating part and annotate the liquid hole intercommunication setting, and be provided with on the concave part be used for with the intercommunicating pore of casing intercommunication to make electrolyte can get into the inside of casing through annotating liquid hole, concave part and intercommunicating pore in proper order. The sealing component is arranged in the concave part and can be switched between an initial state and a deformation state, and in the initial state, the sealing component is used for sealing the liquid injection hole and enabling the liquid injection hole to be disconnected with the concave part so as to effectively seal the liquid injection hole, improve the sealing performance of the end cover assembly and further ensure the safety performance of the battery monomer. In the deformation state, the sealing part deforms and enables the liquid injection hole to be communicated with the concave part, so that electrolyte can effectively flow into the shell through the liquid injection hole, and the liquid injection requirement of the battery cell is met.

In some embodiments, at least one of the bottom wall and the side wall of the recess is provided with a communication hole.

Through this mode of setting, can improve annotate liquid efficiency, can also increase the circulation route that electrolyte got into in the casing, guarantee annotate the liquid requirement.

In some embodiments, the number of communication holes is plural, and the plural communication holes are arranged at intervals.

Through this setting up mode, can make electrolyte flow into inside the casing along a plurality of intercommunicating pore, increased electrolyte flow direction to dispersed the impact force to the inside diaphragm of casing when electrolyte flows, avoided the diaphragm to turn over after being impacted, guaranteed the security performance of battery, simultaneously, the setting of above-mentioned a plurality of intercommunicating pore can also improve annotate liquid efficiency.

In some embodiments, the sealing member includes a support and a closure member disposed on a side of the support facing the liquid injection hole in a thickness direction, the closure member closing the liquid injection hole in an initial state disposed facing the opening of the insulating member, the support being deformable under a first preset pressure and the closure member being separated from the liquid injection hole, so that the sealing member is switched from the initial state to the deformed state.

Through this setting up mode, at initial state, sealing member's closure piece can seal annotate the opening that liquid hole faced the insulating part to make external foreign matter unable entering annotate liquid hole and the electrolyte in the casing unable overflow or blowout, can improve sealing performance, thereby guarantee the single safe and reliable of battery. The support piece of the sealing component can deform under the first preset pressure, and the sealing piece is separated from the liquid injection hole, so that the sealing component is switched from an initial state to a deformed state, and electrolyte can flow into the concave part through the liquid injection hole to meet the liquid injection requirement. The above structural form of the sealing component can meet the functional requirements, and is simple in structure and molded.

In some embodiments, the support member includes two or more support units, and in the circumferential direction of the liquid injection hole, the two or more support units are disposed at intervals around the closure member, one end of each support unit is connected to the closure member and the other end is supported in the recess, and each support unit is deformable under a first preset pressure.

Through the support element that makes the support element include more than two interval settings to make the one end and the closure of every support element be connected and the other end supports in the concave part, can enough guarantee the supporting role to the closure, satisfy the sealing requirement to annotate the liquid hole at initial state. Moreover, the support unit can move in the direction away from each other to deform under the first preset pressure, so that the sealing piece can be separated from the liquid injection hole, electrolyte can enter through the liquid injection hole, and the liquid injection requirement is guaranteed. Meanwhile, the arrangement form can also ensure the integrity of the supporting piece and improve the safety and reliability of the sealing component.

In some embodiments, the spacing between two adjacent support units is equal in the circumferential direction. Through this mode setting, can improve the atress homogeneity of support piece when deformation to make the deformation of sealing member can be more even, improve support piece's life, can also improve notes liquid efficiency and sealed effect.

In some embodiments, the support units have a shape of arc rod, and each support unit is convexly disposed in a direction away from each other in a radial direction of the liquid injection hole.

Through setting up the supporting element to be the curved shaft shape and in the radial direction of annotating the liquid hole to the protruding mode of direction that keeps away from each other, can make the supporting element possess certain elasticity, when annotating the liquid pressure and reach first preset pressure, do benefit to bending deformation to guarantee to annotate the liquid requirement. And moreover, the support unit has better bending resistance and fracture resistance when being deformed, and the service life of the support unit is prolonged, so that the effectiveness of the sealing part is ensured, and the safety performance of the battery monomer is further ensured.

In some embodiments, the support unit is at least partially abutted against a side wall of the recess. Through this mode setting, when the supporting element deformation, the lateral wall of concave part can provide supporting element holding power, prevents that the supporting element from setting up in the one end of concave part and taking place the displacement, can not resume to original position even for the closure can set up with annotating the liquid hole relatively all the time, in order to improve sealing member's reliability.

In some embodiments, the support further comprises a support ring, an axis of the support ring extending in a thickness direction, the closure member closing an end of the support ring in the thickness direction facing the liquid injection hole, an outer diameter of the support ring being larger than a bore diameter of the liquid injection hole.

Through this mode setting to make the support ring can evenly scatter in self with the transmission to support piece more evenly with the pushing force who receives, improve support piece's life. And, through making the external diameter of holding ring be greater than the aperture of annotating the liquid hole, under initial condition, the holding ring can the butt be located on the wall of annotating liquid hole week side outer fringe in the end cover, guarantees that the closure member sets up with annotating the liquid hole relatively, guarantees sealed effect.

In some embodiments, the support ring is disposed coaxially with the injection port. Through this mode setting, can make the supporting ring even atress to make the supporting ring can push away evenly to support piece deformation, improve its reliability. In addition, the arrangement is convenient for processing and positioning, and reduces the preparation difficulty.

In some embodiments, the closure is in the form of an arcuate tab structure projecting in the thickness direction toward the side of the end cap. Through this mode setting, do benefit to the liquid pressure that flows to the closure piece and reach first preset pressure and make support piece deformation, satisfy the notes liquid requirement. And when the sealing part is switched to an initial state from a deformation state after the liquid injection is finished, the arc-shaped sheet structure which is arranged in a protruding mode can also partially enter the liquid injection hole, and the sealing effect is better guaranteed.

In some embodiments, a pressure relief portion is provided on the closure member for venting gas from the housing at a second predetermined pressure from the liquid injection hole. Through this setting up mode to make gaseous discharge, can guarantee the safety in utilization of battery monomer.

In some embodiments, the pressure relief portion comprises a score or relief valve provided on the closure. By this means, the effectiveness of the closure can be further improved and the versatility is improved.

In some embodiments, the injection hole is a stepped through hole, and a radial dimension of a side of the injection hole facing the insulator is smaller than a radial dimension of a side of the injection hole facing away from the insulator in a thickness direction. Through the arrangement, the flowing speed of the electrolyte can be accelerated, so that the liquid injection efficiency is improved.

In a second aspect, embodiments of the present application provide a battery cell, including: a housing having an opening; an electrode assembly disposed within the case; the end cap assembly provided by any one of the embodiments of the first aspect is configured to close the opening and to be electrically connected to the electrode assembly.

In the technical scheme of this application embodiment, because the battery monomer includes the end cover subassembly that has good sealing performance, consequently, the battery monomer's that this application embodiment provided security performance that guarantees that can be better.

In a third aspect, embodiments of the present application provide a battery, including: the battery cell provided by any one of the embodiments of the second aspect.

In the technical scheme of the embodiment of the application, since the battery comprises the battery monomer with good safety performance, the safety performance of the battery provided by the embodiment of the application can be better ensured.

In a fourth aspect, any one embodiment provides an electrical device, including a battery provided in any one embodiment of the third aspect. The battery is connected to the electricity utilization device and provides electric energy to the electricity utilization device.

The foregoing description is only an overview of the technical solutions of the present application, and may be implemented according to the content of the specification in order to make the technical means of the present application more clearly understood, and in order to make the above-mentioned and other objects, features and advantages of the present application more clearly understood, the following detailed description of the present application will be given.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Also, like reference numerals are used to designate like parts throughout the figures.

In the drawings:

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

fig. 2 is a schematic structural diagram of a battery according to an embodiment of the present disclosure;

fig. 3 is a schematic structural view of a battery module according to an embodiment of the present disclosure;

fig. 4 is an exploded view of a battery cell according to an embodiment of the present disclosure;

FIG. 5 is a schematic partial structural view of an end cap assembly according to one embodiment of the present disclosure;

FIG. 6 is a cross-sectional view taken along the direction A-A in FIG. 5;

FIG. 7 is an enlarged schematic view at P in FIG. 6;

FIG. 8 is a schematic view of an insulator in an end cap assembly according to one embodiment of the present disclosure;

fig. 9 is a top view of the insulator of fig. 8.

FIG. 10 is a schematic view of a partially exploded construction of an end cap assembly according to one embodiment of the present application

FIG. 11 is a schematic structural view of a seal member in an end cap assembly according to one embodiment of the present application.

Reference numerals in the specific embodiments are as follows:

1-a vehicle; 10-battery; 11-a controller; 12-motor;

20-battery module; 21-battery cell; 21 a-electrode terminals; 211-a housing; 211 a-openings; 212-an electrode assembly; 212 a-positive electrode tab;

30 boxes; 301-a first tank portion; 302-a first tank portion;

40-end cap assembly; 41-end caps; 411-liquid injection hole; 42-insulating member; 421-recesses; 421 a-a bottom wall; 421 b-sidewalls; 4211-communicating holes;

43-a sealing member; 431-support; 4311-a support unit; 4312-support rings; 432-a closure; 4321A-pressure relief section;

x-thickness direction; y-circumferential direction; z-radial.

Detailed Description

Embodiments of the technical solutions of the present application will be described in detail below with reference to the accompanying drawings. The following examples are only for more clearly illustrating the technical solutions of the present application, and thus are only examples, and are not intended to limit the scope of protection of the present application.

It should be noted that unless otherwise indicated, technical or scientific terms used in the embodiments of the present application should be given the ordinary meanings as understood by those skilled in the art to which the embodiments of the present application belong.

In the description of the embodiments of the present application, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the embodiments of the present application.

Furthermore, the technical terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. In the description of the embodiments of the present application, the meaning of "plurality" is two or more unless explicitly defined otherwise.

In the description of the embodiments of the present application, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured" and the like are to be construed broadly and may, for example, be fixedly connected, detachably connected, or be integrated; or may be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the embodiments of the present application will be understood by those of ordinary skill in the art according to the specific circumstances.

In the description of embodiments of the present application, unless explicitly specified and limited otherwise, a first feature "up" or "down" on a second feature may be that the first and second features are in direct contact, or that the first and second features are in indirect contact via an intermediary. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

Currently, the application of power batteries is more widespread from the development of market situation. 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, and the like, and a plurality of fields such as 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 in the preparation process of the existing battery cell, the electrolyte is generally injected into the battery cell through the injection hole on the end cover assembly, and in the injection process, if the injection speed is too high or the flow is too high, the membrane of the corresponding battery cell below the injection hole is folded, which causes a safety risk. Before the final sealing operation is completed, the sealing glue nails need to be driven into the liquid injection holes, then the sealing glue nails are welded, and in the process, external glue nails or foreign matters easily enter the battery cells through the liquid injection holes, so that safety risks are also caused. In addition, during the process of liquid injection or movement of the battery unit, the electrolyte in the battery unit is easy to overflow or spray out due to internal and external pressure difference, inertia or clamping by equipment, so that other parts are polluted.

In order to improve the safety performance of the battery cell, the applicant researches and discovers that the end cover assembly of the battery cell can be improved so as to improve the tightness of the end cover assembly, thereby improving the safety performance of the battery cell.

Based on the above considerations, in order to solve the problem of the safety performance of the battery cell, the applicant has conducted intensive studies to design an end cap assembly of the battery cell,

in such a battery cell, by adding a sealing member in the end cap assembly, the sealing member is disposed between the liquid injection hole of the end cap and the recess portion of the insulating member having the connection hole, and the sealing member can be switched between an initial state in which the sealing member is used to close the liquid injection hole and to disconnect the liquid injection hole from the recess portion, so as to improve sealability of the end cap assembly, thereby preventing external foreign matters from entering the battery cell, and preventing the electrolyte in the battery cell from overflowing or being ejected, thereby improving safety performance of the battery cell. In the deformed state, the sealing part deforms and enables the liquid injection hole to be communicated with the concave part, so that electrolyte is smoothly injected into the battery cell, and the preparation process of the battery cell is completed.

The technical scheme described in the embodiment of the application is applicable to battery monomers, batteries and power utilization devices using the batteries.

The electric device may be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, an electric tool, or the like. 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; spacecraft including airplanes, rockets, space planes, spacecraft, and the like; the electric toy includes fixed or mobile electric toys, such as a game machine, an electric car toy, an electric ship toy, and an electric airplane toy; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railroad power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete shakers, and electric planers, among others. The embodiment of the application does not limit the electric device in particular.

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

Referring to fig. 1, fig. 1 is a schematic structural diagram of a vehicle 1 according to some embodiments of the present application. The vehicle 1 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-extending vehicle. The battery 10 is provided in the interior of the vehicle 1, and the battery 10 may be provided at the bottom or at the head or at the tail of the vehicle 1. The battery 10 may be used for power supply of the vehicle 1, for example, the battery 10 may serve as an operating power source of the vehicle 1. The vehicle 1 may further comprise a controller 11 and a motor 12, the controller 11 being adapted to control the battery 10 to supply power to the motor 12, e.g. for operating power requirements during start-up, navigation and driving of the vehicle 1.

In some embodiments of the present application, the battery 10 may not only serve as an operating power source for the vehicle 1, but also as a driving power source for the vehicle 1, providing driving power for the vehicle 1 instead of or in part instead of fuel oil or natural gas.

Referring to fig. 2 and 3, fig. 2 is a schematic structural diagram of a battery 10 according to an embodiment of the present application, and fig. 3 is a schematic structural diagram of a battery module 20 according to an embodiment of the present application. To meet various usage power requirements, the battery 10 may include a plurality of battery cells 21, and the battery cells 21 refer to the smallest units constituting the battery module 20 or the battery pack. A plurality of battery cells 21 may be connected in series and/or parallel together via electrode terminals for various applications. The battery referred to in this application includes a battery module 20 or a battery pack. The plurality of battery cells 21 may be connected in series or parallel or in parallel, and the series-parallel connection refers to a mixture of series connection and parallel connection. In the embodiment of the present application, the plurality of battery cells 21 may directly constitute the battery 10, or may first constitute the battery module 20, and then constitute the battery 10 from the battery module 20.

As shown in fig. 2, the battery 10 includes a case 30 and a battery cell 21, and the battery cell 21 is accommodated in the case 30.

The case 30 may have a simple three-dimensional structure such as a rectangular parallelepiped, a cylinder, or a sphere, or may have a complex three-dimensional structure formed by combining simple three-dimensional structures such as a rectangular parallelepiped, a cylinder, or a sphere, which is not limited in the embodiment of the present application. The material of the case 30 may be an alloy material such as an aluminum alloy or an iron alloy, a polymer material such as polycarbonate or polyisocyanurate foam, or a composite material such as glass fiber and epoxy resin, which is not limited in this embodiment.

The case 30 is for accommodating the battery cells 21, and the case 30 may have various structures. In some embodiments, the case 30 may include a first case portion 301 and a second case portion 302, the first case portion 301 and the second case portion 302 being covered with each other, the first case portion 301 and the second case portion 302 together defining an accommodating space for accommodating the battery cell 21. The second case portion 302 may have a hollow structure with one end opened, the first case portion 301 has a plate-like structure, and the first case portion 301 is covered on the opening side of the second case portion 302 to form a case 30 having an accommodation space; the first case 301 and the second case 302 may each have a hollow structure with one side opened, and the opening side of the first case 301 is covered with the opening side of the second case 302 to form the case 30 having the accommodation space. Of course, the first and second case portions 301 and 302 may be of various shapes, such as a cylinder, a rectangular parallelepiped, or the like.

In order to improve the sealing property after the first and second case portions 301 and 302 are connected, a sealing member, such as a sealant, a gasket, or the like, may be provided between the first and second case portions 301 and 302.

Assuming that the first housing portion 301 is covered on top of the second housing portion 302, the first housing portion 301 may also be referred to as an upper case cover, and the second housing portion 302 may also be referred to as a lower case.

In the battery, the number of the battery cells 21 may be one or more. If the number of the battery cells 21 is plural, the plurality of battery cells 21 may be connected in series or parallel or a series-parallel connection, and the series-parallel connection refers to that the plurality of battery cells 21 are connected in series or parallel. The plurality of battery cells 21 can be directly connected in series or in parallel or in series-parallel, and then the whole formed by the plurality of battery cells 21 is accommodated in the box body; of course, a plurality of battery cells 21 may be connected in series or parallel or series-parallel to form the battery module 20, and then the plurality of battery modules 20 may be connected in series or parallel or series-parallel to form a whole and be accommodated in the case 30.

With continued reference to fig. 3, in some embodiments, the plurality of battery cells 21 are provided, and the plurality of battery cells 21 are connected in series or in parallel or in series-parallel to form the battery module 20. The plurality of battery modules 20 are then connected in series or parallel or a series-parallel combination to form a unit and are accommodated in the case 30.

The plurality of battery cells 21 in the battery module 20 may be electrically connected through a bus bar member to realize parallel connection or series-parallel connection of the plurality of battery cells 21 in the battery module 20.

In the present application, the battery cell 21 may include a lithium ion battery cell, a sodium ion battery cell, a magnesium ion battery cell, or the like, which is not limited in the embodiment of the present application. The battery cell 21 may be in a cylindrical shape, a flat shape, a rectangular parallelepiped shape, or other shapes, etc., which is not limited in the embodiment of the present application. The battery cells 21 are generally divided into three types in a package manner: the cylindrical battery cells 21, the square battery cells 21, and the pouch battery cells 21 are not limited thereto. However, for simplicity of description, the following embodiments will be described by taking the square battery cell 21 as an example.

Referring to fig. 4, fig. 4 is a schematic exploded view of a battery cell 21 according to some embodiments of the present application. The battery cell 21 refers to the smallest unit constituting the battery. The battery cell 21 includes an end cap assembly 40, a case 211, and an electrode assembly 212.

The case 211 is an assembly for mating with the end cap assembly 40 to form an internal environment of the battery cell 21, wherein the formed internal environment may be used to house the electrode assembly 212, an electrolyte (not shown in the drawings), and other components. The case 211 and the cap assembly 40 may be separate members, and an opening 211a may be provided in the case 211, and the interior environment of the battery cell 21 may be formed by covering the opening 211a with the cap assembly 40 at the opening 211 a. The end cap assembly 40 and the housing 211 may be integrated, and specifically, the end cap assembly 40 and the housing 211 may form a common connection surface before other components are put into the housing, and when the interior of the housing 211 needs to be sealed, the end cap assembly 40 is covered with the housing 211. The housing 211 may be of various shapes and various sizes, such as rectangular parallelepiped, cylindrical, hexagonal prism, etc. Specifically, the shape of the case 211 may be determined according to the specific shape and size of the electrode assembly 212. The material of the housing 211 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 electrode assembly 212 is a component in which electrochemical reactions occur in the battery cells 21. One or more electrode assemblies 212 may be contained within the housing 211. The electrode assembly 212 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is generally provided between the positive electrode sheet and the negative electrode sheet. The portions of the positive electrode sheet and the negative electrode sheet having the active material constitute the main body portion of the electrode assembly, and the portions of the positive electrode sheet and the negative electrode sheet having no active material constitute the tabs, respectively. The positive electrode tab 212a and the negative electrode tab 212b may be located at one end of the main body or located at two ends of the main body. During charge and discharge of the battery, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tab is connected to the electrode terminal 21a to form a current loop.

Referring to fig. 5 to 7, the cap assembly 40 includes a cap 41, an insulator 42, and a sealing member 43.

The end cap 41 has a pouring hole 411. The insulator 42 is connected to one side of the end cap 41 in the thickness direction X, the insulator 42 is provided with a recess 421 communicating with the liquid filling hole 411, and the recess 421 is provided with a communication hole 4211 communicating with the housing 211. The sealing member 43 is at least partially disposed in the recess 421, and the sealing member 43 is switchable between an initial state in which the sealing member 43 is configured to close the liquid inlet 411 and disconnect the liquid inlet 411 from the recess 421, and a deformed state in which the sealing member 43 is deformed and the liquid inlet 411 is in communication with the recess 421.

With continued reference to fig. 4-6, the end cap assembly 40 refers to a member that covers the opening 211a of the housing 211 to isolate the internal environment of the battery cell 21 from the external environment. Without limitation, the shape of the end cap assembly 40 may be adapted to the shape of the housing 211 to fit the housing 211. Alternatively, the end cap assembly 40 may be made of a material having a certain hardness and strength (such as an aluminum alloy), so that the end cap assembly 40 is not easily deformed when being extruded and collided, and the battery cell 21 has a higher structural strength, and the safety performance is improved. The cap assembly 40 may be provided with functional parts such as electrode terminals 21 a. The electrode terminal 21a may be used to be electrically connected with the electrode assembly 212 for outputting or inputting electric power of the battery cell 21. The material of the end cap assembly 40 may be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not particularly limited in this embodiment.

In some embodiments, end cap assembly 40 includes end cap 41, and end cap 41 may be provided with a fill hole 411 for filling electrolyte into housing 211. In some embodiments, the end cap assembly 40 further includes an insulator 42 disposed inside, and the insulator 42 may serve to isolate the electrode assembly 213 from the end cap assembly 40 within the case 211 to reduce the risk of short circuits. By way of example, the insulator 42 may be plastic, rubber, or the like.

The end cap 41 has a liquid filling hole 411, and the electrolyte can pass through the liquid filling hole 411 to enter the inside of the case 211. Alternatively, the shape of the pouring orifice 411 may be a regular geometric shape, such as a circle, an ellipse, a regular polygon. Of course, the electrolyte may be in an irregular geometric shape, and the present application is not limited to a specific shape, as long as the injection requirement of the electrolyte can be satisfied.

Alternatively, the liquid injection hole 411 may be provided in the thickness direction X of the end cap 41, but may be provided obliquely with respect to the thickness direction X of the end cap 41.

Alternatively, the liquid filling hole 411 may be provided between the mounting hole for mounting the electrode terminal 21a and the vent hole for mounting the explosion-proof member, but may be provided at other positions of the end cap 41.

The liquid injection hole 411 may be formed by various means such as press forming, milling forming, etc., which is not particularly limited in the embodiment of the present application.

The insulator 42 is connected to one side of the end cap 41 in the thickness direction X, the recess 421 of the insulator 42 is provided in communication with the liquid injection hole 411, and the recess 421 is provided with a communication hole 4211 for communicating with the case 211, so that the electrolyte can enter the case 211 through the liquid injection hole 411, the recess 421 and the communication hole 4211 in this order.

In some embodiments, the gas inside the housing 211 can also be discharged through the liquid filling hole 411, specifically, in the battery cell 21, multiple charge and discharge cycles are performed, there is a side reaction, and the gas is continuously generated, and the gas may be generated in a thermal expansion or thermal runaway state of the battery cell 21, so that the gas is discharged, and the use safety of the battery cell 21 can be ensured.

The orthographic projection shape of the concave portion 421 in the thickness direction X of the pouring hole 411 may be a circle, an ellipse, a polygon, or the like, and is not particularly limited in this application.

Alternatively, the number of the communication holes 4211 may be one, but may be plural.

Alternatively, the insulating member 42 and the recess 421 may be integrally formed, so as to reduce cost and improve manufacturing efficiency. Of course, the insulating member 42 and the recess 421 can be provided separately, and can be matched according to different requirements, so as to improve the flexibility and versatility of use.

Optionally, the insulating member 42 may be molded by injection molding of fluoroplastic or die-cutting of fluororubber, so as to have good electrical insulation properties, high heat resistance, oil resistance, solvent resistance, wear resistance, moisture resistance and low temperature resistance, which is conducive to prolonging the service life of the insulating member 42, being capable of replacing the design of pole injection molding and sealing rings, reducing assembly parts, and being beneficial to simplifying the production process.

The sealing member 43 is at least partially disposed in the recess 421, and of course, the sealing member 43 may be entirely disposed in the recess 421. When the sealing member 43 is entirely located in the recess 421, a side of the sealing member 43 facing away from the recess 421 may be flush with a side of the end cap 41 adjacent to the recess 421 in the thickness direction X of the liquid injection hole 411.

By providing the recess 421 on the insulator 42 and making the sealing member 43 at least partially accommodated in the recess 421, the occupied space of the whole end cap assembly 40 can be reduced, and the installation of the end cap 41 can be positioned by the provision of the recess 421, so that the difficulty in assembling the end cap 41 and the insulator 42 can be reduced.

Alternatively, at least part of the sealing member 43 may be provided in the pouring spout 411, and of course, the sealing member 43 may be provided around the pouring spout 411.

By providing the seal member 43 between the liquid filling hole 411 and the communication hole 4211 of the recess 421, external impurity particles can be prevented from entering the case 211, and safety performance of the battery cell 21 can be ensured. Meanwhile, the above arrangement can also prevent the electrolyte injected from the injection hole 411 from directly acting on the communication hole 4211 of the concave portion 421, reduce the impact force on the concave portion 421 and the communication hole 4211, reduce the probability of deformation of the concave portion 421 and the communication hole 4211, further improve the service life of the insulating member 42, and ensure the safety and reliability of the battery cell 21. In addition, the electrolyte can be prevented from directly impacting the diaphragm of the battery cell 21 to prevent the diaphragm from being folded or even failing, so that the sealing part 42 also has a certain buffer function to improve the service life of the battery cell 21 and ensure the safety and reliability.

The sealing member 43 can be switched between an initial state and a deformation state, in the initial state, the sealing member 43 is used for sealing the liquid injection hole 411 and enabling the liquid injection hole 411 to be disconnected from the concave portion 421 so as to effectively seal the liquid injection hole 411, prevent external foreign matters from entering the housing 211 to pollute the battery cell 21, generate a safety risk problem, and also prevent the electrolyte of the battery cell 21 in the housing 211 from overflowing or being sprayed out through the liquid injection hole 411 to pollute the housing 211, an explosion-proof valve and other components.

By providing the sealing member 43, the sealing performance of the end cap assembly 40 can be improved on the basis of ensuring the liquid injection requirement, thereby ensuring the safety performance of the battery cell 21.

In the deformed state, the sealing member 43 deforms and causes the liquid filling hole 411 to communicate with the concave portion 421, so that the electrolyte can effectively flow into the case 211 via the liquid filling hole 411, satisfying the liquid filling requirement for the battery cell 21. Specifically, the sealing member 43 deforms and allows the liquid filling hole 411 to communicate with the recess 421, and the electrolyte can flow from the liquid filling hole 411 to the surface of the sealing member 43 and then flow into the recess 421, and then enter the inside of the housing 211 through the communication hole 4211, completing the liquid filling process.

The sealing member 43 can be switched between the initial state and the deformed state, so that the end cover assembly 40 can integrate the liquid injection function and the sealing function, the sealing requirement can be ensured to ensure the safety performance of the battery cell 21, and the liquid injection function can be realized to complete the preparation of the battery cell 21.

Referring to fig. 7 to 9, in some embodiments, at least one of a bottom wall 421a and a side wall 421b of the recess 421 is provided with a communication hole 4211.

Alternatively, the bottom wall 421a of the recess 421 may be provided with the communication hole 4211, and of course, the side wall 421b of the recess 421 may be provided with the communication hole 4211, and of course, both the bottom wall 421a and the side wall 421b of the recess 421 may be provided with the communication hole 4211.

The recess 421 may be of various shapes, such as a rectangular parallelepiped, a cylinder. Taking the recess 421 as a rectangular parallelepiped, the recess 421 may have five walls, one bottom wall 421a and four side walls 421b together forming the recess 421, and at least one of the bottom wall 421a and the side walls 421b is provided with a communication hole 4211. Taking the concave portion 421 as a cylinder, the concave portion 421 may have two walls, a bottom wall 421a and a circumferential side wall 421b, the circumferential side wall 421b is enclosed on the edge of the bottom wall 421a, the circumferential side wall 421b and the bottom wall 421a together form the concave portion 421, and at least one of the bottom wall 421a and the circumferential side wall 421b is provided with a communication hole 4211.

By way of example, the bottom wall 421a and the side wall 421b of the recess 421 may be provided with the communication hole 4211, which can improve the liquid injection efficiency of the end cap assembly 40. And, can also increase the circulation path that electrolyte got into in the casing 211, guarantee annotate the liquid requirement, disperse the impact force of electrolyte inflow to the diaphragm of battery monomer 21 in the casing 211 simultaneously, prevent that the diaphragm from turning over the phenomenon to the safe and reliable of battery monomer 21 has been improved. In addition, by providing the communication hole 4211 in both the bottom wall 421a and the side wall 421b of the recess 421, the force of the impact of the electrolyte on the communication hole 4211 of the recess 421 can be reduced, and the service life of the recess 421 can be increased, thereby improving the reliability of the cap assembly 40.

In some embodiments, the number of communication holes 4211 is plural, and the plural communication holes 4211 are arranged at intervals.

Through the arrangement, electrolyte can flow into the shell 211 along the plurality of communication holes 4211, so that the flowing direction of the electrolyte is increased, the impact force on the diaphragm inside the shell 211 when the electrolyte flows is dispersed, the diaphragm is prevented from being folded after being impacted, the safety performance of the battery cell 21 is ensured, and meanwhile, the liquid injection efficiency can be improved by adopting the arrangement mode of the plurality of connection holes 4211.

Also, the number of communication holes 4211 is set to be plural, and it is also possible to prevent the passage of electrolyte or gas in the case from only one communication hole 4211 to cause failure of this communication hole 4211, even damage to the entire recess 421, thereby improving the service life and reliability of the insulating member 42.

The shape of each communication hole 4211 among the plurality of communication holes 4211 may be the same, for example, each of the plurality of communication holes 4211 may be circular, elliptical, or oval, etc. Of course, the shape of each communication hole 4211 of the plurality of communication holes 4211 may be different or at least a part of the communication holes 4211 may be different, for example, a part of the communication holes 4211 of the plurality of communication holes 4211 may be circular, and a part of the communication holes 4211 may be elliptical, oval, polygonal, or the like.

Illustratively, the plurality of communication holes 4211 are identical in shape and equal in area. The plurality of communication holes 4211 may have the same shape as each other, and for example, each of the plurality of communication holes 4211 may be a circular hole. Of course, the plurality of communication holes 4211 may be elliptical holes or polygonal holes, and may be regular polygonal holes. The same area of the plurality of communication holes 4211 means that the areas of any two communication holes 4211 are the same. For example, when the plurality of communication holes 4211 are circular holes, the diameters of any two communication holes 4211 are the same, and when the plurality of communication holes 4211 are elliptical holes, the major axis dimensions of any two communication holes 4211 are equal and the minor axis dimensions are equal.

By making the shapes and the areas of the plurality of communication holes 4211 the same, it is advantageous for the liquid or gas to uniformly and quickly pass through the plurality of communication holes 4211 during the liquid injection process or the gas discharge process. The pressure applied to the concave portion 421 and the corresponding portion is the same, and deformation of the concave portion 421 due to uneven distribution of the liquid or gas passing through the plurality of communication holes 4211 is avoided. Meanwhile, the plurality of communication holes 4211 may be machined by pressing or milling, and by making the plurality of communication holes 4211 identical in shape and area, the same machining process may be used to machine each communication hole 4211, which may simplify the machining process, reduce the machining cost, and improve the molding efficiency.

The distribution pattern of the plurality of communication holes 4211 on the bottom wall 421a and the side wall 421b of the recess 421 is not particularly limited, and may be, for example, a row-column distribution or an array distribution, or may be sequentially distributed along an annular track, or may be sequentially distributed along a linear track or a curved track.

The plurality of communication holes 4211 are disposed at intervals, that is, at least a portion of the hole walls of two adjacent communication holes 4211 are disposed at intervals, and the intervals between two adjacent communication holes 4211 may be the same, or may be different.

Referring to fig. 7 to 11, in some embodiments, the sealing member 43 includes a support 431 and a closing member 432, the closing member 432 is disposed on a side of the support 431 facing the liquid injection hole 411 in the thickness direction X, in an initial state, the closing member 432 closes the opening of the liquid injection hole 411 facing the insulating member 42, the support 431 is deformable under a first preset pressure, and the closing member 432 is separated from the liquid injection hole 411, such that the sealing member 43 is switched from the initial state to the deformed state.

The first preset pressure is that, during the process of injecting the electrolyte into the injection hole 411, the liquid pressure applied to the side of the sealing member 43 near the injection hole 411 just deforms the supporting member 431 of the sealing member 43, so that the injection hole 411 is communicated with the recess 421, and the electrolyte can smoothly flow into the recess 421.

The closing piece 432 of the sealing member 43 is provided at a side of the supporting piece 431 facing the liquid injection hole 411 in the thickness direction X, and in an initial state, the closing piece 432 can close the opening of the liquid injection hole 411 facing the insulating piece 42, so that external impurity particles cannot enter the liquid injection hole 411 and electrolyte in the case 211 cannot overflow or be ejected, sealing performance can be improved, and safety and reliability of the battery cell 21 are ensured.

The support 431 of the sealing member 43 is deformable under a first preset pressure and the closure 432 is separated from the liquid injection hole 411, so that the sealing member 43 is switched from an initial state to a deformed state, specifically, under the first preset pressure, the closure 432 is pressurized to push the support 431 to deform, so that the closure 432 no longer closes the liquid injection hole 411, and the electrolyte can flow from the liquid injection hole 411 to the surface of the sealing member 43 and then flow into the concave portion 421, and then enter the inside of the housing 211 through the communication hole 4211, thereby completing the liquid injection process.

By adopting the above-described structure of the seal member 43, the functional requirements can be satisfied, and the structure is simple and molding is used.

With continued reference to fig. 11, in some embodiments, the support member 431 includes two or more support units 4311, and in the circumferential direction Y of the liquid injection hole 411, the two or more support units 4311 are disposed around the closure member 432 at intervals, one end of each support unit 4311 is connected to the closure member 432 and the other end is supported by the recess 421, and each support unit 4311 is capable of being deformed under a first preset pressure.

Alternatively, the support 431 may include two support units 4311, and of course, the support 431 may also include a plurality of support units 4311. The two or more support units 4311 may be disposed at regular intervals around the closure 432, and of course, may be disposed at regular intervals around the closure 432.

By making the support member 431 include two or more support units 4311 disposed at intervals, and making one end of each support unit 4311 connected to the closure member 431 and the other end supported in the recess 421, the support function of the closure member 431 can be ensured, and the sealing requirement of the closure member 431 on the liquid injection hole 411 in the initial state can be satisfied. Moreover, the support unit 4311 can move away from each other to deform under the first preset pressure, so that the sealing member 431 can be separated from the liquid injection hole 411, and the electrolyte can enter through the liquid injection hole 411 to ensure the liquid injection requirement.

The concave portion 421 can provide supporting force for the supporting unit 4311 when the supporting unit 4311 is deformed, so that the supporting unit 4311 is deformed to ensure that the end cover 41 and the insulating member 42 have enough gaps to enable electrolyte to be injected into the concave portion 421, and meanwhile, the arrangement mode can also prevent the supporting unit 4311 from transitional deformation or displacement caused by overlarge pressure of the electrolyte, ensure the integrity of the supporting member 431 and improve the safety and reliability of the sealing member 43.

In some embodiments, the spacing between adjacent two support units 4311 is equal along the circumferential direction Y.

Through this setting, can guarantee that every supporting element 4311 receives same pressure and deformation, avoid every supporting element 4311 atress uneven and lead to certain supporting element 4311 excessive deformation to take place fracture or damage phenomenon to improve support 431's reliability and life, thereby improve sealing member 43's validity, further guarantee the security performance of battery cell 21.

The support member 431 includes four support units 4311, and the four support units 4311 are disposed at equal intervals around the circumferential direction Y of the liquid injection hole 411, so that the better support seal member 432 seals the opening of the liquid injection hole 411 facing the insulating member 42, thereby improving the liquid injection efficiency and sealing effect.

In some embodiments, the support units 4311 are in a shape of arc, and each support unit 4311 is convexly disposed in a direction away from each other in a radial direction Z of the liquid injection hole 411.

Alternatively, the support unit 4311 may be provided in an arc-shaped rod shape, and of course, the support unit 4311 may be provided in other shapes, such as a straight plate shape, a folded line shape, and the like.

The support units 4311 are formed in an arc-shaped rod shape, and the support units 4311 are protruded in a direction away from each other in the radial direction Z of the liquid injection hole 411, that is, a contour line formed by sequentially connecting one end of each support unit 4311 near the concave portion 421 is larger than a contour line formed by sequentially connecting one end of each support unit 4311 near the closing member 432.

Through setting up supporting element 4311 to be the curved shaft shape and in the radial Z of annotating liquid hole 411 to the mode of keeping away from each other protrusion, can make supporting element 4311 possess certain elasticity, when annotating liquid pressure and reaching first preset pressure, do benefit to bending deformation to guarantee annotating liquid requirement. And, can also make the supporting element 4311 have better bending resistance, fracture resistance ability when deformation, improve the life of supporting element 4311 to guarantee the validity of sealing member 43, further guarantee the security performance of battery cell 21.

Alternatively, the center of gravity positions of the support units 4311 are sequentially connected to form a contour line larger than a contour line formed by sequentially connecting one end of each support unit 4311 near the recess 421.

With continued reference to fig. 7 and 11, in some embodiments, the support unit 4311 at least partially abuts against the sidewall 421b of the recess 421.

That is, the supporting unit 4311 is supported at a position where one end of the concave portion 421 is connected to the bottom wall 421a and the side wall 421b of the concave portion 421, and in this way, when the supporting unit 4311 is deformed, the side wall 421b and the bottom wall 421a of the concave portion 421 can cooperate to provide the supporting force to the supporting unit 4311, so as to prevent the supporting unit 4311 from being displaced at one end of the concave portion 421, thereby preventing the supporting unit 4311 from being unable to restore to the original position, and enabling the closing member 432 to be always disposed opposite to the filling hole 411, so as to improve the reliability of the sealing member 43.

Optionally, at least a portion of each support unit 4311 abuts against the side wall 421b of the recess 421, so that the sealing member 43 is conveniently mounted and positioned, and the manufacturing efficiency is improved.

In some embodiments, the support member 431 further includes a support ring 4312, the axis of the support ring 4312 extends along the thickness direction X, the sealing member 432 seals one end of the support ring 4312 facing the liquid injection hole 411 in the thickness direction X, and the outer diameter of the support ring 4312 is larger than the aperture of the liquid injection hole 411.

The axis of the support ring 4312 extends in the thickness direction X, that is, the support ring 4312 may be an annular body having a certain thickness.

Optionally, the closing member 432 is disposed inside the supporting ring 4312 and connected to the inner wall of the supporting ring 4312, and the supporting member 431 is disposed outside the supporting ring 4312 and connected to the outer wall of the supporting ring 4312.

The sealing member 432 seals the opening of the liquid injection hole 411 facing the insulating member 42, and the outer diameter of the support ring 4312 is larger than the aperture of the liquid injection hole 411, that is, in the initial state, the support ring 4312 can be abutted against the wall of the end cover 41 located at the outer edge of the periphery of the liquid injection hole 411, so that the sealing effect is ensured due to the opposite arrangement of the sealing member 432 and the liquid injection hole 431. In the deformation process, that is, when the injection pressure reaches the first preset pressure, the sealing member 432 is pressed against the supporting ring 4312, and a certain pressure is transmitted to the supporting member 431 through the supporting ring 4312 to deform the supporting member 431.

The supporting ring 4312 is added to avoid the problem that the supporting member 431 is directly subjected to the pushing force so as to be easy to fail, and the supporting ring 4312 has a certain thickness, so that the received pushing force can be uniformly dispersed on the supporting member 4312 to be more uniformly transmitted to the supporting member 431, and the service life of the supporting member 431 is prolonged.

In some embodiments, the support ring 4312 is disposed coaxially with the fill port 411.

By this arrangement, the supporting ring 4312 can be uniformly stressed, so that the supporting ring 4312 can be uniformly pushed against the supporting member 431 to deform, and the reliability of the supporting member is improved.

In addition, the arrangement is convenient for processing and positioning, and reduces the preparation difficulty.

In some embodiments, the closure 432 is in the form of an arcuate tab projecting in the thickness direction X toward the side of the end cap 41.

Through this mode setting, in annotate the liquid in-process, can increase the contact surface of closure 432 and electrolyte and meet, the electrolyte can flow to the week side by the bulge position of closure 432, does benefit to and reaches first preset pressure in order to make support 431 deformation to satisfy annotate the liquid requirement, do benefit to the validity that improves sealing member 43. And, when sealing member 43 switches to initial state from deformation state after annotating the liquid, the arc piece structure that the protrusion set up can also partly get into annotate in the liquid hole 411, better assurance seal effect.

Optionally, the central position of the sealing member 432 is protruded toward the side of the end cap 41 along the thickness direction X, so that the liquid can uniformly flow from the central position of the sealing member 432 to the peripheral position, and each portion of the supporting member 431 can be subjected to the same pressure, so that each portion of the supporting member 431 can be deformed simultaneously, the liquid injection efficiency can be improved, and the service life of the sealing member 43 can be also improved.

With continued reference to fig. 6 to 9, in some embodiments, the sealing member 432 is provided with a pressure release portion 4321, and the pressure release portion 4321 is used to discharge the gas in the housing 211 from the liquid injection hole 411 under the second preset pressure.

The second preset pressure means that the gas inside the housing 211 enters the recess 421 through the communication hole 4211, and at this time, the pressure applied to the side of the sealing member 43 near the recess 421 just deforms the sealing member 43, so that the liquid injection hole 411 is communicated with the recess 421, and the gas can smoothly flow into the liquid injection hole 411 and then to the external environment.

Alternatively, the closure 432 is provided in an arc-shaped piece structure protruding toward the side of the end cap 41 in the thickness direction X, so that the gas reaching the second preset pressure can be facilitated to push against the pressure release portion 4321 on the protruding closure 432 to discharge the gas.

The pressure release portion 4321 is configured to release the gas in the housing 211 from the liquid injection hole 411 under the second preset pressure, and it is understood that only the gas in the housing 211 can be released through the pressure release portion 4321 of the sealing member 43 under the second preset pressure, and the liquid is not released through the pressure release portion 4321, and other portions of the sealing member 43 are not deformed due to the influence of the second preset pressure, so that the gas in the housing 211 can be released, the safety performance of the battery cell 21 is ensured, the electrolyte in the housing 211 can be prevented from being sprayed or overflowed, the other components are prevented from being polluted by the electrolyte, and the safety and reliability of the battery cell 21 are further ensured.

In addition, because the pressure release portion 4321 can discharge the gas in the housing 211, the pressure in the housing 211 can be released, so that the continuous stress of the pressure in the housing 211 to the sealing member 43 is reduced, the risk that the sealing member 43 is damaged or fails to cause the leakage of the battery cell 21 or the external impurities enter the housing 211 is reduced, and the service life and the safety performance of the battery cell 21 are further improved.

Optionally, the pressure release portion 4321 may be made of a soft rubber material, and of course, may be made of other materials, which is not limited in this application, and only the pressure release portion 4321 needs to be capable of exhausting gas when reaching the second preset pressure, and keep a sealing effect under other working conditions.

In some embodiments, the pressure relief 4321 comprises a score or relief valve provided on the closure 432.

Alternatively, the pressure relief portion 4321 may include a notch provided on the closure 432, wherein the notch may be a cross-shaped notch or a straight notch.

Alternatively, the score locations provided on the closure 432 may be made of a soft plastic material, and the score automatically opens the vent gas when the recess 421 is exposed to air such that the pressure in the recess 421 is greater than the pressure in the fill hole 411. When the air in the concave portion 421 is exhausted so that the pressure in the concave portion 421 is not greater than the pressure of the liquid injection hole 411, the score can be automatically sealed due to the suction effect and the pressure effect of the soft rubber material, so as to achieve the effects of leakage prevention and pollution prevention.

Illustratively, a score may be provided at a central location of the closure 432 to enable various portions of the closure 432 to remain uniformly stressed during venting, improving the useful life of the closure 432.

Optionally, the pressure release portion 4321 may include a pressure release valve disposed on the closure member 432, where the pressure release valve may be a one-way pressure release valve, so as to ensure that the pressure release portion 4321 can only pass through the gas inside the housing 211, thereby ensuring safety and reliability.

When the recess 421 is filled with air so that the pressure in the recess 421 is greater than the pressure in the filling hole 411, the relief valve automatically opens the exhaust gas. When the air in the concave portion 421 is exhausted, so that the pressure in the concave portion 421 is not greater than the pressure of the liquid injection hole 411, the pressure release valve can be automatically sealed under the pressure action, so that the effects of leakage prevention and pollution prevention are achieved.

For example, a pressure relief valve may be provided in an intermediate position of the closure 432 to allow various portions of the closure 432 to remain uniformly stressed during venting, improving the service life of the closure 432.

With continued reference to fig. 6 and 7, in some embodiments, the injection hole 411 is a stepped through hole, and in the thickness direction X, the radial Z dimension of the injection hole 411 facing the insulating member 42 is smaller than the radial Z dimension of the injection hole facing away from the insulating member 42.

The liquid injection hole 411 is a stepped through hole, and optionally, the liquid injection hole 411 includes a first through hole, a second through hole and a third through hole, where the first through hole is set away from the insulating member 42, and the third through hole is set near the insulating member 42, and the second through hole is communicated with the first through hole and the third through hole.

The radial Z dimension of the injection hole 411 towards the insulating part 42 side is smaller than the radial Z dimension away from the insulating part 42 side, namely, the radial Z dimension of the third through hole is smaller than the radial Z dimension of the first through hole, through the arrangement, electrolyte can enter the third through hole with small radial Z dimension from the first through hole with large radial Z dimension in the injection process, and the flowing speed of the electrolyte can be accelerated, so that the injection efficiency is improved.

Alternatively, the axial dimensions of the first through hole, the second through hole, and the third through hole are sequentially reduced in the thickness direction X to better increase the rate of the flow of the electrolyte.

Alternatively, on the side of the liquid injection hole 411 facing away from the insulating member 42, the radial Z dimensions of the first through hole, the second through hole, and the third through hole decrease in order. Optionally, the hole wall of the third through hole is perpendicular to the axial direction, the hole walls of the first through hole and the second through hole are inclined to the axial direction, and the inclination angle of the side wall of the second through hole is larger than that of the side wall of the first through hole, so that the flowing speed of the electrolyte is accelerated better.

According to some embodiments of the present application, there is also provided a battery cell 21 including a housing 211, an electrode assembly, and an end cap assembly 40 provided by any of the above embodiments.

The housing 211 has an opening. The electrode assembly is disposed within the case 211. The cap assembly 40 is provided to close the opening and is electrically connected to the electrode assembly.

The battery cell 21 provided by the embodiment of the application can prevent external foreign matters from entering, and can also prevent electrolyte from overflowing or being sprayed out, so that the safety and the reliability are improved.

According to some embodiments of the present application, there is also provided a battery 10 including the battery cell 21 provided in any of the above embodiments.

In the technical solution of the embodiment of the present application, since the battery 10 includes the battery monomer 21 with good safety performance, the safety performance of the battery 10 provided in the embodiment of the present application can be better ensured.

According to some embodiments of the present application, there is also provided an electrical device, including the battery 10 provided in any of the above embodiments, and the battery 10 is used to provide electrical energy to the electrical device. The powered device may be any of the devices or systems described above that employ the battery 10.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the embodiments, and are intended to be included within the scope of the claims and description. 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

1. An end cap assembly, comprising:

the end cover is provided with a liquid injection hole;

the insulating piece is connected to one side of the end cover in the thickness direction of the insulating piece, the insulating piece is provided with a concave part communicated with the liquid injection hole, and the concave part is provided with a communication hole communicated with the shell;

and the sealing part is at least partially arranged in the concave part, can be switched between an initial state and a deformation state, is used for sealing the liquid injection hole and enabling the liquid injection hole to be disconnected with the concave part, and is deformed and enables the liquid injection hole to be communicated with the concave part.

2. The end cap assembly of claim 1, wherein at least one of a bottom wall and a side wall of the recess is provided with the communication hole.

3. The end cap assembly of claim 1, wherein the number of communication holes is plural, and the plural communication holes are spaced apart.

4. The end cap assembly according to claim 1, wherein the sealing member includes a support member and a closing member provided to a side of the support member facing the liquid injection hole in the thickness direction, the closing member closing the opening of the liquid injection hole facing the insulating member in the initial state, the support member being deformable under a first preset pressure and the closing member being separated from the liquid injection hole, so that the sealing member is switched from the initial state to the deformed state.

5. The end cap assembly of claim 4, wherein the support member comprises two or more support units spaced around the closure member in a circumferential direction of the liquid injection hole, one end of each support unit being connected to the closure member and the other end being supported in the recess, each support unit being deformable under the first preset pressure.

6. The end cap assembly of claim 5, wherein the spacing between adjacent two of the support units is equal along the circumferential direction.

7. The end cap assembly of claim 5, wherein the support units are arc-shaped rod-like, each of the support units being convexly disposed in a direction away from each other in a radial direction of the liquid injection hole.

8. The end cap assembly of claim 5, wherein the support unit at least partially abuts a sidewall of the recess.

9. The end cap assembly of claim 4, wherein the support member further comprises a support ring, an axis of the support ring extending in the thickness direction, the closure closing an end of the support ring in the thickness direction toward the pour hole, an outer diameter of the support ring being greater than a bore diameter of the pour hole.

10. The end cap assembly of claim 9, wherein the support ring is disposed coaxially with the injection port.

11. The end cap assembly of claim 4, wherein the closure is an arcuate tab structure projecting in the thickness direction toward the end cap side.

12. The end cap assembly of claim 4, wherein the closure is provided with a pressure relief portion for venting gas from the housing at a second predetermined pressure from the fill port.

13. The end cap assembly of claim 12, wherein the pressure relief portion comprises a score or a pressure relief valve provided on the closure.

14. The end cap assembly of claim 1, wherein the injection hole is a stepped through hole, and a radial dimension of the injection hole toward the insulator is smaller than a radial dimension of the injection hole away from the insulator in the thickness direction.

15. A battery cell, comprising:

a housing having an opening;

an electrode assembly disposed within the housing;

the end cap assembly of any one of claims 1 to 14, for closing the opening and being electrically connected to the electrode assembly.

16. A battery comprising the battery cell of claim 15.

17. An electrical device comprising the battery of claim 16.