End cover assembly, battery monomer, battery and electric device

Abstract

The utility model relates to an end cover assembly, a battery monomer, a battery and a power utilization device, and the end cover assembly comprises a cover plate which is provided with a liquid injection hole; the insulating part is arranged on one side of the cover plate in the axial direction of the liquid injection hole, and the insulating part is provided with a through hole; the sealing assembly is connected with the insulating part and comprises an elastic part and a sealing part, and the elastic part is connected between the sealing part and the insulating part; the sealing assembly has a first state and a second state; in the first state, the sealing piece is inserted into the liquid injection hole and seals the liquid injection hole; in the second state, the sealing piece moves in the axial direction and compresses the elastic piece, and the liquid injection hole is communicated with the through hole. According to the end cover assembly, the battery monomer, the battery and the electric device provided by the embodiment of the invention, the liquid leakage risk in the transfer process is reduced by the end cover assembly, so that the reliability of the end cover assembly is improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to an end cover assembly, a battery cell, a battery and an electrical device. Background Art

[0002] Energy conservation and emission reduction are the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their advantages in energy conservation and environmental protection. For electric vehicles, battery technology is an important factor in their development.

[0003] In the related art, during the transportation of the battery cell, there is a risk of leakage at the injection hole of the end cover assembly, which reduces the reliability of the end cover assembly. Utility Model Content

[0004] The embodiments of the present application provide an end cap assembly, a battery cell, a battery, and an electrical device. The end cap assembly reduces the risk of leakage during transportation, thereby improving the reliability of the end cap assembly.

[0005] On the one hand, according to an embodiment of the present application, an end cover assembly is provided, including: a cover plate, having an injection hole; an insulating member, arranged on one side of the cover plate along the axial direction of the injection hole, the insulating member having a through hole; a sealing assembly, connected to the insulating member, the sealing assembly including an elastic member and a sealing member, the elastic member being connected between the sealing member and the insulating member; the sealing assembly has a first state and a second state; in the first state, the sealing member is inserted into the injection hole and seals the injection hole; in the second state, the sealing member moves axially and compresses the elastic member, and the injection hole is connected to the through hole.

[0006] An end cap assembly provided by an embodiment of the present application includes a cover plate, an insulating member, and a sealing assembly. Since the sealing assembly includes an elastic member and a sealing member and has a first state and a second state, when electrolyte needs to be injected into the battery cell, the sealing member can be pressed and force can be applied to the sealing member through the injection tube, so that the sealing member moves axially and compresses the elastic member, and the injection hole is connected to the through hole, and the electrolyte in the injection tube can enter through the injection hole and the through hole to meet the injection requirements. After the injection tube is separated from the sealing member, the elastic member recovers its deformation, pushes the sealing member to move in the opposite direction to the injection hole and closes the injection hole, so that the electrolyte of the battery cell after injection cannot overflow through the injection hole during transportation, thereby improving the reliability of the end cap assembly.

[0007] According to one aspect of an embodiment of the present application, the sealing member has an end facing the cover plate with a cavity connected to the injection hole, and the wall portion of the cavity enclosed by the insulating member is provided with an opening connected to the cavity. In a first state, the cover plate closes the opening setting, and in a second state, the opening protrudes from the cover plate setting and is connected to the through hole.

[0008] An end cap assembly provided by an embodiment of the present application is provided with a cavity connected to the injection hole and an opening connected to the cavity on the side of the seal facing the cover plate, so that when the end cap assembly is used for a battery cell and is injected, the injection tube can be docked with the cavity of the seal, and the electrolyte in the injection tube will enter the cavity during the process of entering. Since the opening is still in a closed state at this time, as the electrolyte continues to accumulate, the seal will be pushed to move axially and compress the elastic member under the pressure of the electrolyte until the opening protrudes from the cover plate and is connected to the through hole, so that the sealing assembly switches from the first state to the second state, and the electrolyte will flow out from the opening to the through hole and enter the battery cell through the through hole. When the electrolyte is injected to a predetermined volume, the injection of the electrolyte can be stopped, so that the injection tube is separated from the end cap assembly. Due to the release of the electrolyte pressure, the seal is reset under the action of the elastic member, the sealing assembly switches to the first state, the opening is closed again, and the seal closes the injection hole, so that the electrolyte of the battery cell after injection cannot overflow through the injection hole during transportation, thereby ensuring reliability.

[0009] According to one aspect of the embodiment of the present application, there are multiple openings, and the multiple openings are arranged at intervals around the axis of the injection hole.

[0010] An end cover assembly provided in an embodiment of the present application can improve the injection efficiency by providing multiple openings, and at the same time, can ensure that the seal is subjected to uniform pressure of the electrolyte in the circumferential direction, ensure smooth movement in the axial direction, and reduce the occurrence of excessive wear on one side or jamming due to deflection during movement.

[0011] According to one aspect of the embodiments of the present application, along the axial direction of the liquid injection hole, the vertical distance from the opening to the end surface of the cover plate facing the insulating member is less than the maximum compression amount of the elastic member.

[0012] An end cap assembly provided by an embodiment of the present application makes the vertical distance from the opening to the end face of the cover plate facing the insulating member smaller than the maximum compression amount of the elastic member, so that when the elastic member is not compressed to the limit position, the opening can protrude from the end cap setting and be connected to the through hole, thereby ensuring the electrolyte injection requirements and preventing the elastic member from being crushed, thereby improving the reliability of the elastic member.

[0013] According to one aspect of the embodiment of the present application, a first cavity is disposed in the insulating member, and the first cavity is located between the opening and the elastic member and is disposed independently of the cavity.

[0014] An end cover assembly provided in an embodiment of the present application can reduce the overall weight of the seal and reduce the difficulty of axial movement of the seal by providing a first cavity.

[0015] According to one aspect of the embodiment of the present application, a concave cavity is provided at one end of the sealing member facing the elastic member, and the elastic member partially extends into the concave cavity and abuts against the bottom wall of the concave cavity.

[0016] An end cover assembly provided in an embodiment of the present application can position and limit the elastic member by setting a cavity on the sealing member, thereby facilitating the installation of the elastic member, reducing the probability of deflection of the elastic member during compression, and ensuring smooth movement of the sealing member.

[0017] According to one aspect of an embodiment of the present application, the insulating part includes an insulating plate and a supporting portion, the insulating plate and the cover plate are stacked and have a through hole, the orthographic projection of the supporting portion on the cover plate covers the through hole and is enclosed with the insulating plate to form an installation cavity, the elastic part and at least part of the sealing part are located in the installation cavity, an outlet is provided on the supporting portion, and the through hole is connected to the outlet.

[0018] According to one aspect of the embodiment of the present application, a guide portion is provided on the support portion, a guide groove extending axially along the injection hole is provided in the guide portion, the sealing member at least partially extends into the guide groove and slidably cooperates with the guide portion, and the elastic member is provided in the guide groove.

[0019] In an end cap assembly provided by one embodiment of the present application, the insulating member adopts the above-mentioned structural form, which can ensure the support and installation of the elastic member. At the same time, the above-mentioned arrangement allows the liquid flowing into the through-hole to flow out through the outlet and enter the battery cell. Since the orthographic projection of the support portion on the cover plate covers the through-hole, the electrolyte entering the through-hole will not directly fall into the battery cell and impact the electrode assembly, but will be blocked by the support portion and flow out from the outlet, thereby reducing the impact damage to the electrode assembly. In addition, after the electrolyte is injected and during the transportation process, even if the battery cell shakes, due to the blocking of the support portion, the electrolyte will not directly impact the through-hole and the injection hole, thereby reducing the probability of electrolyte leakage.

[0020] According to one aspect of the embodiment of the present application, the guide portion is columnar and is arranged around the elastic member, and the insulating plate, the support portion and the guide portion are an integrated structure.

[0021] The end cap assembly provided in one embodiment of the present application can ensure the positioning of the elastic member and reduce the difficulty of molding the insulating member through the above-mentioned configuration, while ensuring the overall strength of the insulating member and improving the reliability of the end cap assembly.

[0022] On the other hand, according to one embodiment of the present application, a battery cell is provided, comprising the above-mentioned end cover assembly.

[0023] On the other hand, according to an embodiment of the present application, a battery is provided, including a box body and the above-mentioned battery cell, wherein the battery cell is accommodated in the box body.

[0024] On the other hand, according to an embodiment of the present application, an electrical device includes the above-mentioned battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The features, advantages and technical effects of exemplary embodiments of the present application will be described below with reference to the accompanying drawings.

[0026] Figure 1 is a schematic diagram of a vehicle according to an embodiment of the present application;

[0027] Figure 2 is a schematic structural diagram of a battery according to an embodiment of the present application;

[0028] Figure 3 is a schematic structural diagram of a battery cell according to an embodiment of the present application;

[0029] Figure 4 is a partial cross-sectional structural schematic diagram of an end cover assembly of an embodiment of the present application;

[0030] Figure 5 yes Figure 4 A partial enlarged view of the middle A;

[0031] Figure 6 It is a partial cross-sectional view of a seal according to an embodiment of the present application.

[0032] in:

[0033] 1- Vehicle;

[0034] 10-battery; 20-battery module; 30-controller; 40-motor;

[0035] 301-first box body; 302-second box body;

[0036] 50-battery cell;

[0037] 51-end cover assembly;

[0038] 511-cover plate; 511a-liquid injection hole;

[0039] 512-insulating member; 5121-insulating plate; 5122-supporting portion; 5122a-horizontal plate; 5122b-connecting plate; 5122c-exit; 5123-installation cavity; 5124-guide portion;

[0040] 513-seal assembly;

[0041] 5131-seal; 5131a-cavity; 5131b-opening; 5131c-recessed cavity; 5131d-first cavity;

[0042] 5132-elastic parts;

[0043] 52-housing;

[0044] 53-electrode assembly;

[0045] X-axis direction.

[0046] In the drawings, the same reference numerals are used for the same components. The drawings are not drawn to scale. DETAILED DESCRIPTION

[0047] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0048] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the embodiments of the present application should have the common meanings understood by technicians in the field to which the embodiments of the present application belong.

[0049] In the description of the embodiments of the present application, the orientations or positional relationships indicated by technical terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", and "circumferential" are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0050] In addition, the technical terms "first", "second", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0051] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0052] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0053] At present, from the perspective of market development, the application of power batteries is becoming more and more extensive. Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields. With the continuous expansion of the application field of power batteries, the market demand is also constantly expanding.

[0054] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in the present application may include a battery module or a battery pack.

[0055] The battery cell may be a secondary battery cell, which refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0056] The battery cell comprises a shell, an end cap assembly, an electrode assembly and an electrolyte. The electrode assembly is arranged in the shell, the electrolyte is filled in the shell, and the end cap assembly is arranged to close the opening of the shell.

[0057] The applicant noted that the battery cells in the related art may be contaminated by electrolyte leakage caused by shaking during the production process due to the battery cell transportation process. At the same time, environmental impurities and moisture may pass through the injection holes of the end cover assembly and may enter the battery cell interior, affecting the battery cell performance.

[0058] Based on the above considerations, the applicant has conducted in-depth research and designed an end cover assembly, including a cover plate, an insulating member and a sealing member. The cover plate has an injection hole, and the insulating member is arranged on one side of the cover plate along the axial direction of the injection hole. The insulating member has a through hole. The sealing member is connected to the insulating member, and the sealing member includes an elastic member and a sealing member. The elastic member is connected between the sealing member and the insulating member. The sealing member has a first state and a second state. In the first state, the sealing member is inserted into the injection hole and seals the injection hole. In the second state, the sealing member moves axially and compresses the elastic member, and the injection hole is connected with the through hole. Since the sealing member includes an elastic member and a sealing member, and the sealing member has a first state and a second state, when it is necessary to inject electrolyte into the battery cell, the sealing member can be pressed and force applied to the sealing member through the injection tube, so that the sealing member moves axially and compresses the elastic member, the injection hole is connected with the through hole, and the electrolyte in the injection tube can enter through the injection hole and the through hole to meet the injection requirements. After the injection tube is separated from the seal, the elastic member recovers its deformation, pushing the seal to move in the opposite direction to the injection hole and closes the injection hole, so that the electrolyte of the battery cell after injection cannot overflow through the injection hole during transportation, thereby improving the reliability of the end cover assembly.

[0059] The technical solutions described in the embodiments of the present application are applicable to various devices that use batteries, such as mobile phones, portable devices, laptop computers, electric vehicles, electric toys, electric tools, electric vehicles, ships and spacecraft, for example, spacecraft include airplanes, rockets, space shuttles and spacecraft, etc.

[0060] It should be understood that the technical solutions described in the embodiments of the present application are not limited to the devices described above, but can also be applied to all devices using batteries. However, for the sake of simplicity, the following embodiments are described using electric vehicles as examples.

[0061] For example, Figure 1 As shown, it is a schematic diagram of the structure of a vehicle 1 according to an embodiment of the present application. The vehicle 1 may be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A motor 40, a controller 30 and a battery 10 may be arranged inside the vehicle 1. The controller 30 is used to control the battery 10 to supply power to the motor 40. For example, a battery 10 may be arranged at the bottom, front or rear of the vehicle 1. The battery 10 may be used to supply power to the vehicle 1. For example, the battery 10 may be used as an operating power source for the vehicle 1, for the circuit system of the vehicle 1, for example, for the working power requirements during the start-up, navigation and operation of the vehicle 1. In another embodiment of the present application, the battery 10 may not only be used as an operating power source for the vehicle 1, but also as a driving power source for the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0062] like Figure 2 as well as Figure 3 As shown, in order to meet different power requirements, the battery 10 may include a plurality of battery cells 50, wherein the plurality of battery cells 50 may be connected in series, in parallel, or in a hybrid connection, wherein the hybrid connection refers to a mixture of series and parallel connections. The battery may also be referred to as a battery pack. Optionally, a plurality of battery cells 50 may first be connected in series, in parallel, or in a hybrid connection to form a battery module 20, and a plurality of battery modules 20 may then be connected in series, in parallel, or in a hybrid connection to form a battery. In other words, a plurality of battery cells 50 may directly form a battery, or may first form a battery module 20, and the battery module 20 may then form a battery.

[0063] For example, Figure 2 , which is a schematic diagram of the structure of a battery 10 according to an embodiment of the present application, the battery 10 may include a plurality of battery cells 50. The battery 10 may also include a box (or cover), the interior of the box is a hollow structure, and the plurality of battery cells are accommodated in the box.

[0064] The box body can be a simple three-dimensional structure such as a single cuboid, cylinder or sphere, or a complex three-dimensional structure composed of simple three-dimensional structures such as cuboids, cylinders or spheres, which is not limited in the embodiments of the present application. The material of the box body can be alloy materials such as aluminum alloy, iron alloy, etc., or polymer materials such as polycarbonate, polyisocyanurate foam plastic, or composite materials such as glass fiber and epoxy resin, which is not limited in the embodiments of the present application.

[0065] The box is used to accommodate the battery cell 50, and the box can be a variety of structures. In some embodiments, the box may include a first box portion 301 and a second box portion 302, the first box portion 301 and the second box portion 302 cover each other, and the first box portion 301 and the second box portion 302 jointly define a storage space for accommodating the battery cell. The second box portion 302 can be a hollow structure with one end open, the first box portion 301 is a plate-like structure, and the first box portion 301 covers the open side of the second box portion 302 to form a box with a storage space; the first box portion 301 and the second box portion 302 can also be a hollow structure with one side open, and the open side of the first box portion 301 covers the open side of the second box portion 302 to form a box with a storage space. Of course, the first box portion 301 and the second box portion 302 can be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0066] In order to improve the sealing performance after the first box body 301 and the second box body 302 are connected, a sealing member, such as a sealant, a sealing ring, etc., may also be provided between the first box body 301 and the second box body 302 .

[0067] Assuming that the first box body portion 301 covers the top of the second box body portion 302 , the first box body portion 301 can also be referred to as an upper box cover, and the second box body portion 302 can also be referred to as a lower box body.

[0068] In the battery 10, there can be one or more battery cells 50. If there are more than one battery cell 50, the battery cells 50 can be connected in series, in parallel, or in a mixed connection. A mixed connection means that the battery cells 50 are both connected in series and in parallel. The battery cells 50 can be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by the battery cells 50 is accommodated in the box; of course, the battery module 20 can also be formed by connecting the battery cells in series, in parallel, or in a mixed connection, and then the battery modules 20 are connected in series, in parallel, or in a mixed connection to form a whole and accommodated in the box.

[0069] The battery cell 50 may include a lithium-ion battery cell, a sodium-ion battery cell, or a magnesium-ion battery cell, etc., which is not limited in the embodiments of the present application. The battery cell 50 may be cylindrical, flat, rectangular, or in other shapes, which is not limited in the embodiments of the present application. The battery cell 50 is generally divided into three types according to the packaging method: cylindrical battery cells, square battery cells, and soft-pack battery cells, which is not limited in the embodiments of the present application. However, for the sake of simplicity, the following embodiments are all described using the cylindrical battery cell 50 as an example.

[0070] like Figure 3 As shown, the battery cell 50 includes a shell 52, an electrode assembly 53 and an end cap assembly 51. The shell 52 is a component used to cooperate with the end cap assembly 51 to form the internal environment of the battery cell 50, wherein the formed internal environment can be used to accommodate the electrode assembly 53, the electrolyte (not shown in the figure) and other components. The shell 52 and the end cap assembly 51 can be independent components, and an opening can be set on the shell 52, and the internal environment of the battery cell 50 is formed by covering the opening with the end cap assembly 51 at the opening. Without limitation, the end cap assembly 51 and the shell 52 can also be integrated. Specifically, the end cap assembly 51 and the shell 52 can form a common connection surface before other components are put into the shell, and when it is necessary to encapsulate the interior of the shell 52, the end cap assembly 51 covers the shell 52. The shell 52 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the shell 52 can be determined according to the specific shape and size of the electrode assembly 53. The shell 52 can be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present application does not impose any special restrictions on this.

[0071] The electrode assembly 53 is a component in the battery cell 50 where electrochemical reactions occur. One or more electrode assemblies 53 may be included in the housing 52. The electrode assembly 53 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The parts of the positive and negative electrode sheets with active materials constitute the main body of the electrode assembly, and the parts of the positive and negative electrode sheets without active materials each constitute a pole ear (not shown in the figure). The positive pole ear and the negative pole ear may be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery, the positive active material and the negative active material react with the electrolyte, and the pole ears connect the electrode terminals to form a current loop.

[0072] The end cap assembly 51 refers to a component that covers the opening of the housing 52 to isolate the internal environment of the battery cell 50 from the external environment. Without limitation, the shape of the end cap assembly 51 can be adapted to the shape of the housing 52 to match the housing 52.

[0073] like Figures 4 to 6 As shown, the end cover assembly 51 includes a cover plate 511, an insulating member 512 and a sealing assembly 513. The cover plate 511 has an injection hole 511a. The insulating member 512 is arranged on one side of the cover plate 511 along the axial direction X of the injection hole 511a. The insulating member 512 has a through hole. The sealing assembly 513 is connected to the insulating member 512. The sealing assembly 513 includes an elastic member 5132 and a sealing member 5131. The elastic member 5132 is connected between the sealing member 5131 and the insulating member 512. The sealing assembly 513 has a first state and a second state. In the first state, the sealing member 5131 is inserted into the injection hole 511a and seals the injection hole 511a. In the second state, the sealing member 5131 moves along the axial direction X and compresses the elastic member 5132, and the injection hole 511a is connected to the through hole.

[0074] The cover plate 511 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the cover plate 511 is not easily deformed when it is squeezed and collided, so that the end cover assembly 51 can have a higher structural strength and the safety performance can also be improved. The material of the cover plate 511 can also be a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present application does not impose any special restrictions on this.

[0075] The shape of the injection hole 511 a provided on the cover plate 511 may be circular or polygonal, and the injection hole 511 a may be provided through the cover plate 511 along the thickness direction of the cover plate 511 .

[0076] The insulating member 512 is disposed on one side of the cover plate 511 in the thickness direction, and the insulating member 512 and the cover plate 511 can be stacked and connected. The area of ​​the through hole disposed on the insulating member 512 can be larger than the connection of the injection hole 511a, and the two can be coaxially disposed or eccentrically disposed.

[0077] The elastic member 5132 includes but is not limited to a spring, a rubber pad, a compressible air bag, etc.

[0078] In the first state, the outer periphery of the sealing member 5131 can be fitted with the wall surface of the injection hole 511a formed by the cover plate 511, and the sealing member 5131 is closed, so that the injection hole 511a and the through hole are blocked by the sealing member 5131, and environmental impurities and moisture cannot enter the through hole through the injection hole 511a, and thus cannot enter the battery cell 50. At the same time, the electrolyte in the battery cell 50 cannot enter the injection hole 511a through the through hole and then leak. In the second state, the sealing member 5131 moves along the axial direction X and compresses the elastic member 5132, and the injection hole 511a is connected with the through hole. In this state, the sealing member 5131 can completely detach from the injection hole 511a, giving way to the injection hole 511a, so that the injection hole 511a is connected with the through hole. Of course, the sealing member 5131 may be partially separated from the injection hole 511a and partially located at the injection hole 511a. In this case, a gap may be formed between the sealing member 5131 and the cover plate 511 to form the wall surface of the injection hole 511a. The sealing member 5131 may also be provided with a connecting structure. When the sealing member 5131 moves so that the connecting structure partially enters the through hole, the through hole and the injection hole 511a are connected.

[0079] An end cap assembly 51 provided in one embodiment of the present application includes a cover plate 511, an insulating member 512 and a sealing assembly 513. Since the sealing assembly 513 includes an elastic member 5132 and a sealing member 5131 and has a first state and a second state, when electrolyte needs to be injected into the battery cell 50, the sealing member 5131 can be pressed and force can be applied to the sealing member 5131 through the injection tube, so that the sealing member 5131 moves along the axial direction X and compresses the elastic member 5132, and the injection hole 511a is connected with the through hole, and the electrolyte in the injection tube can enter through the injection hole 511a and the through hole to meet the injection requirements. After the injection tube is separated from the sealing member 5131, the elastic member 5132 recovers its deformation, pushes the sealing member 5131 to move in the opposite direction to the injection hole 511a and closes the injection hole 511a, so that the electrolyte of the battery cell 50 after injection cannot overflow through the injection hole 511a during transportation, thereby improving the reliability of the end cap assembly 51.

[0080] In some optional embodiments, an end cap assembly 51 provided by an embodiment of the present application has a sealing member 5131 having a cavity 5131a connected to the injection hole 511a at one end facing the cover plate 511, and the insulating member 512 encloses a wall portion of the cavity 5131a and is provided with an opening 5131b connected to the cavity 5131a. In a first state, the cover plate 511 closes the opening 5131b, and in a second state, the opening 5131b protrudes out of the cover plate 511 and is connected to the through hole.

[0081] The number of the openings 5131b may be one or more. When there are more than one openings 5131b, the plurality of openings 5131b may be arranged at intervals around the axis of the injection hole 511a.

[0082] The opening 5131b may start from one end of the sealing member 5131 along the axial direction X of the injection hole 511a toward the end cover. Of course, the opening 5131b may be spaced apart from the sealing member 5131 at both ends of the axial direction X of the injection hole 511a.

[0083] In the first state, the opening 5131b can be completely located in the injection hole 511a, and the opening 5131b can be covered and closed by the wall surface of the injection hole 511a enclosed by the cover plate 511. In the second state, since the sealing member 5131 moves along the axial direction X and compresses the elastic member 5132, the relative position between the opening 5131b and the injection hole 511a can be changed as the sealing member 5131 moves, and the opening 5131b protrudes from the cover plate 511, so that at least a part of it is not closed by the cover plate 511, so as to communicate with the through hole.

[0084] An end cap assembly 51 provided in an embodiment of the present application is provided with a cavity 5131a connected to the injection hole 511a and an opening 5131b connected to the cavity 5131a on the side of the sealing member 5131 facing the cover plate 511, so that when the end cap assembly 51 is used for the battery cell 50 and is injected, the injection tube can be connected to the cavity 5131a of the sealing member 5131, and the electrolyte in the injection tube will enter the cavity 5131a during the entry process. Since the opening 5131b is still in a closed state at this time, as the electrolyte continues to accumulate, the pressure of the electrolyte will push the sealing member 5131 to move along the axial direction X and compress the elastic member 5132 until the opening 5131b protrudes out of the cover plate 511 and is connected to the through hole. In this way, the sealing member 513 is switched from the first state to the second state, and the electrolyte will flow out from the opening 5131b to the through hole and enter the interior of the battery cell 50 through the through hole. After the electrolyte is injected to a predetermined volume, the injection of the electrolyte can be stopped, so that the injection tube is separated from the end cover assembly 51. As the electrolyte pressure is released, the seal 5131 is reset under the action of the elastic member 5132, and the sealing assembly 513 is switched to the first state. The opening 5131b is closed again, and the seal 5131 closes the injection hole 511a, so that the electrolyte of the battery cell after injection cannot overflow through the injection hole 511a during transportation, thereby ensuring reliability.

[0085] In some optional embodiments, in an end cover assembly 51 provided by an embodiment of the present application, the number of openings 5131b is multiple, and the multiple openings 5131b are arranged at intervals around the axis of the injection hole 511a.

[0086] The number of the openings 5131b may be two, three or more.

[0087] An end cover assembly 51 provided in an embodiment of the present application can improve the injection efficiency by setting a plurality of openings 5131b, and at the same time, can ensure that the seal 5131 is subjected to uniform pressure of the electrolyte in the circumferential direction, ensure smooth movement in the axial direction X, and reduce the occurrence of excessive wear on one side or jamming due to deflection during movement.

[0088] In some optional embodiments, in an end cover assembly 51 provided by an embodiment of the present application, along the axial direction X of the injection hole 511a, the vertical distance from the opening 5131b to the end surface of the cover plate 511 facing the insulating member 512 is less than the maximum compression amount of the elastic member 5132.

[0089] The vertical distance from the opening 5131b to the end surface of the cover plate 511 facing the insulating member 512 can be understood as: the minimum vertical distance from the wall surface enclosing the opening 5131b to the end surface of the cover plate 511 facing the insulating member 512 in the axial direction X.

[0090] The maximum compression amount of the elastic member 5132 may be understood as: the absolute value of the difference between the length of the elastic member 5132 in the first state and the length of the elastic member 5132 in the second state.

[0091] An end cap assembly 51 provided in an embodiment of the present application makes the vertical distance from the opening 5131b to the end surface of the cover plate 511 facing the insulating member 512 smaller than the maximum compression amount of the elastic member 5132, so that when the elastic member 5132 is not pressed to the limit position, the opening 5131b can protrude from the cover plate 511 and be connected to the through hole, thereby ensuring the electrolyte injection requirements and preventing the elastic member 5132 from being crushed, thereby improving the reliability of the elastic member 5132.

[0092] In some optional embodiments, in an end cover assembly 51 provided by an embodiment of the present application, a cavity 5131c is provided at one end of the sealing member 5131 facing the elastic member 5132, and the elastic member 5132 partially extends into the cavity 5131c and abuts against the bottom wall of the cavity 5131c.

[0093] The shape of the concave cavity 5131c can match the shape of the elastic member 5132. For example, when the elastic member 5132 is a spring, the shape of the concave cavity 5131c can be a columnar form. The elastic member 5132 can be located in the concave cavity 5131c. The elastic member 5132 and the bottom wall of the concave cavity 5131c can abut against each other, or can be connected to each other, such as by welding or bonding.

[0094] An end cover assembly 51 provided in an embodiment of the present application can position and limit the elastic member 5132 by setting a cavity 5131c on the sealing member 5131, thereby facilitating the installation of the elastic member 5132, reducing the probability of the elastic member 5132 being deflected during the compression process, and ensuring the smooth movement of the sealing member 5131.

[0095] In some optional embodiments, in an end cap assembly 51 provided by an embodiment of the present application, a first cavity 5131d is provided in the insulating member 512, and the first cavity 5131d is located between the opening 5131b and the elastic member 5132 and is independently provided with the cavity 5131a.

[0096] The first cavity 5131d and the cavity 5131a are independently arranged, which can be understood as the two being disconnected and not connected to each other. The first cavity 5131d can be formed in the sealing member 5131 by injection molding or the like.

[0097] The end cover assembly 51 provided in one embodiment of the present application can reduce the overall weight of the seal 5131 and reduce the difficulty of movement of the seal 5131 in the axial direction X by setting the first cavity 5131d.

[0098] In some optional embodiments, an end cover assembly 51 provided by an embodiment of the present application, the insulating member 512 includes an insulating plate 5121 and a supporting portion 5122, the insulating plate 5121 and the cover plate 511 are stacked and have a through hole, the orthographic projection of the supporting portion 5122 on the cover plate 511 covers the through hole and is enclosed with the insulating plate 5121 to form an installation cavity 5123, the elastic member 5132 and at least a portion of the sealing member 5131 are located in the installation cavity 5123, and an outlet 5122c is provided on the supporting portion 5122, and the through hole is connected to the outlet 5122c.

[0099] The shape of the insulating plate 5121 may match the shape of the cover plate 511 , and the two may be connected in a fixed manner, for example, by bonding or by an integral connection.

[0100] In an end cap assembly 51 provided by one embodiment of the present application, the insulating member 512 adopts the above-mentioned structural form, which can ensure the support and installation of the elastic member 5132. At the same time, the above-mentioned arrangement allows the electrolyte flowing into the through hole to flow out through the outlet 5122c and enter the battery cell 50. Since the orthographic projection of the support portion 5122 on the cover plate 511 covers the through hole, the electrolyte entering the through hole will not directly fall into the battery cell 50 and impact the electrode assembly 53, but will be blocked by the support portion 5122 and flow out from the outlet 5122c, thereby reducing the impact damage to the electrode assembly 53. In addition, after the electrolyte is injected and during the transportation process, even if the battery cell 50 shakes, due to the blocking of the support portion 5122, the electrolyte will not directly impact the through hole and the injection hole 511a, thereby reducing the probability of electrolyte leakage.

[0101] In some optional embodiments, the support portion 5122 may protrude from the insulating plate 5121 in the axial direction X. In some optional embodiments, it may include a horizontal plate 5122a and a connecting plate 5122b, wherein the horizontal plate 5122a is disposed on the side of the insulating plate 5121 away from the cover plate 511, and the connecting plates 5122b are disposed in pairs and distributed on both sides of the horizontal plate 5122a, and each connecting plate 5122b is connected between the horizontal plate 5122a and the insulating plate 5121. The support portion 5122 adopts the above-mentioned structural form, which is conducive to the installation and support of the elastic member 5132, and at the same time, the cavity is conducive to ensuring the formation of the installation cavity 5123 and the outlet 5122c.

[0102] In some optional embodiments, in an end cap assembly 51 provided by an embodiment of the present application, the guide portion 5124 is columnar and is arranged around the elastic member 5132, and the insulating plate 5121, the support portion 5122 and the guide portion 5124 are an integrated structure.

[0103] The insulating plate 5121 , the supporting portion 5122 and the guiding portion 5124 may be formed by integral injection molding or the like.

[0104] An end cap assembly 51 provided by an embodiment of the present application makes the guide portion 5124 columnar and arranged around the elastic member 5132, and makes the insulating plate 5121, the support portion 5122 and the guide portion 5124 an integrated structure. This can ensure the positioning of the elastic member 5132 and reduce the difficulty of molding the insulating member 512, while ensuring the overall strength of the insulating member 512 and improving the reliability of the end cap assembly 51.

[0105] like Figures 4 to 6As shown, an embodiment of the present application provides an end cover assembly 51, including a cover plate 511, an insulating member 512 and a sealing assembly 513, the cover plate 511 has a liquid injection hole 511a, the insulating member 512 is arranged on one side of the cover plate 511 along the axial direction X of the liquid injection hole 511a, the insulating member 512 has a through hole, the sealing assembly 513 is connected to the insulating member 512, and the sealing assembly 513 includes an elastic member 5132 and a sealing member 5131, the elastic member 5132 is connected to the sealing member 5131 and the insulating member 51 2; the end of the sealing member 5131 facing the cover plate 511 has a cavity 5131a connected to the injection hole 511a, and the wall of the insulating member 512 encloses a plurality of openings 5131b connected to the cavity 5131a. The plurality of openings 5131b are arranged at intervals around the axis of the injection hole 511a. Along the axial direction X of the injection hole 511a, the vertical distance from the opening 5131b to the end surface of the cover plate 511 facing the insulating member 512 is less than the maximum compression amount of the elastic member 5132. The sealing assembly 513 has a first state and a second state; in the first state, the cover plate 511 closes the opening 5131b, and in the second state, the opening 5131b protrudes from the cover plate 511 and is connected to the through hole. A first cavity 5131d is arranged in the insulating member 512, and the first cavity 5131d is located between the opening 5131b and the elastic member 5132 and is independently arranged from the cavity 5131a. A concave cavity 5131 c is provided at one end of the sealing member 5131 facing the elastic member 5132 , and a portion of the elastic member 5132 extends into the concave cavity 5131 c and abuts against the bottom wall of the concave cavity 5131 c . The insulating member 512 includes an insulating plate 5121 and a supporting portion 5122. The insulating plate 5121 and the cover plate 511 are stacked and have a through hole. The orthographic projection of the supporting portion 5122 on the cover plate 511 covers the through hole and is enclosed with the insulating plate 5121 to form an installation cavity 5123. The elastic member 5132 and at least part of the sealing member 5131 are located in the installation cavity 5123. The supporting portion 5122 is provided with an outlet, and the through hole is connected to the outlet. The supporting portion 5122 can protrude from the insulating plate 5121 in the axial direction X, and can include a horizontal plate 5122a and a connecting plate 5122b. The horizontal plate 5122a is provided on the side of the insulating plate 5121 away from the cover plate 511, and the connecting plates 5122b are provided in pairs and distributed on both sides of the horizontal plate 5122a. Each connecting plate 5122b is connected between the horizontal plate 5122a and the insulating plate 5121. The support portion 5122 is provided with a guide portion 5124, and a guide groove extending along the axial direction X of the injection hole 511a is provided in the guide portion 5124. The sealing member 5131 at least partially extends into the guide groove and slidably cooperates with the guide portion 5124, and the elastic member 5132 is disposed in the guide groove. The guide portion 5124 is columnar and is disposed around the elastic member 5132. The insulating plate 5121, the support portion 5122 and the guide portion 5124 are an integrated structure.

[0106] On the other hand, according to one embodiment of the present application, a battery cell is provided, comprising the above-mentioned end cover assembly 51 .

[0107] On the other hand, according to an embodiment of the present application, a battery is provided, comprising the above-mentioned battery cell, wherein the battery cell is accommodated in a box.

[0108] On the other hand, according to the present application, an electrical device includes the above-mentioned battery.

[0109] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present application. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An end cap assembly, characterized in that: include: A cover plate having a liquid injection hole; An insulating member, arranged on one side of the cover plate along the axial direction of the liquid injection hole, and the insulating member has a through hole; A sealing component connected to the insulating member, the sealing component comprising an elastic member and a sealing member, the elastic member being connected between the sealing member and the insulating member; the sealing component has a first state and a second state; In the first state, the sealing member is inserted into the injection hole and seals the injection hole; in the second state, the sealing member moves along the axial direction and compresses the elastic member, and the injection hole is communicated with the through hole.

2. The end cap assembly according to claim 1, characterized in that: The sealing member has an end facing the cover plate with a cavity connected to the injection hole, and the insulating member encloses a wall portion of the cavity with an opening connected to the cavity. In the first state, the cover plate closes the opening, and in the second state, the opening protrudes from the cover plate and is connected to the through hole.

3. The end cap assembly according to claim 2, characterized in that: The number of the openings is multiple, and the multiple openings are arranged at intervals around the axis of the injection hole.

4. The end cap assembly according to claim 2, characterized in that: Along the axial direction of the liquid injection hole, a vertical distance from the opening to an end surface of the cover plate facing the insulating member is less than a maximum compression amount of the elastic member.

5. The end cap assembly according to claim 2, characterized in that: A first cavity is disposed in the insulating member, and the first cavity is located between the opening and the elastic member and is independently disposed from the cavity.

6. The end cap assembly according to any one of claims 1 to 5, characterized in that: A concave cavity is arranged at one end of the sealing member facing the elastic member, and a portion of the elastic member extends into the concave cavity and abuts against a bottom wall of the concave cavity.

7. The end cap assembly according to any one of claims 1 to 5, characterized in that: The insulating member includes an insulating plate and a supporting portion, wherein the insulating plate and the cover plate are stacked and have the through hole, the orthographic projection of the supporting portion on the cover plate covers the through hole and is enclosed with the insulating plate to form an installation cavity, the elastic member and at least part of the sealing member are located in the installation cavity, an outlet is provided on the supporting portion, and the through hole is connected to the outlet.

8. The end cap assembly according to claim 7, characterized in that: The support portion is provided with a guide portion, the guide portion is provided with a guide groove extending along the axial direction of the injection hole, the sealing member at least partially extends into the guide groove and slidably cooperates with the guide portion, and the elastic member is arranged in the guide groove.

9. The end cap assembly according to claim 8, characterized in that: The guide portion is columnar and is disposed around the elastic member. The insulating plate, the support portion and the guide portion are an integrated structure.

10. A battery cell, characterized in that: Comprising the end cover assembly according to any one of claims 1 to 9.

11. A battery, characterized in that: The invention comprises a box body and the battery cell according to claim 10, wherein the battery cell is accommodated in the box body.

12. An electrical device, characterized in that: Comprising the battery of claim 11.

Images