Top cover assembly, battery and electric equipment

Abstract

The utility model provides a top cover assembly, a battery and electric equipment. The top cover assembly comprises a top cover and lower plastic. The top cover is provided with a first pressure relief hole and a first mounting groove, the first mounting groove and the first pressure relief hole are coaxially arranged and communicated, the first mounting groove is used for being connected with a pressure relief valve assembly, the first mounting groove comprises a first connecting surface, the first connecting surface forms the bottom wall of at least part of the first mounting groove, and the first connecting surface is connected to the outer edge of the first pressure relief hole; in the thickness direction of the top cover assembly, the distance between the first connecting face and an opening of the first mounting groove is gradually decreased from the end connected with the first pressure relief hole to the end away from the first pressure relief hole. The lower plastic is connected to the top cover and provided with a second pressure relief hole, and the second pressure relief hole is communicated with the first pressure relief hole and used for allowing the electrolyte to pass through. According to the technical scheme, exhaust paths of the battery can be increased, and the service life of the battery cell is guaranteed.

Description

Technical Field

[0001] This application relates to the field of energy storage technology, and in particular to a top cover assembly, a battery, and an electrical device. Background Technology

[0002] With the development of clean energy, batteries with recyclable characteristics are becoming increasingly popular. During battery use, chemical reactions occur inside the cell, producing a large amount of gas. Therefore, an explosion-proof valve structure is generally installed in the top cover assembly. The large amount of gas generated inside the cell can break through the explosion-proof valve and be discharged to the outside of the battery. However, although the explosion-proof valve can be opened to discharge gas to the outside of the battery, opening the valve can easily lead to a reduction in the life of the cell. Utility Model Content

[0003] Embodiments of this application provide a top cover assembly, a battery, and an electrical device that can increase the venting path of the battery and ensure cell life.

[0004] In a first aspect, this application provides a top cover assembly, the top cover assembly comprising:

[0005] A top cover includes a first surface for facing away from the battery cell. The top cover has a first pressure relief hole and a first mounting groove. The first pressure relief hole penetrates the top cover along its thickness direction. The opening of the first mounting groove is located on the first surface. The first mounting groove is coaxially arranged with and communicates with the first pressure relief hole. The first mounting groove is used to connect with a pressure relief valve assembly. The first mounting groove includes a first connecting surface that forms at least a portion of the bottom wall of the first mounting groove. The first connecting surface is connected to and surrounds the outer edge of the first pressure relief hole. In the thickness direction of the top cover assembly, the distance between the first connecting surface and the opening of the first mounting groove gradually decreases from the end connected to the first pressure relief hole towards the end away from the first pressure relief hole.

[0006] The lower plastic is connected to the top cover. The lower plastic has a second pressure relief hole, which penetrates the lower plastic along its thickness direction. The second pressure relief hole communicates with the first pressure relief hole and is used to allow the electrolyte to pass through.

[0007] During battery use, chemical reactions occur inside the battery cell, producing a large amount of gas. If too much gas accumulates, the battery can easily explode. Therefore, an explosion-proof valve assembly is usually installed in the top cover. The large amount of gas generated inside the battery cell can break through the explosion-proof valve and be discharged to the outside of the battery. However, once the explosion-proof valve explodes, it cannot be reused, and the explosion of the explosion-proof valve will also greatly reduce the lifespan of the battery cell.

[0008] Therefore, in the embodiments of this application, by providing a pressure relief valve assembly in the top cover assembly, the gas generated by the battery cell can enter the first pressure relief hole of the top cover through the second pressure relief hole in the lower plastic, and then enter the interior of the pressure relief valve assembly connected to the first mounting groove, and finally be discharged to the outside of the battery through the pressure relief valve assembly. That is, by providing a pressure relief valve assembly in the top cover assembly, an additional venting path for venting the battery can be added, and the impact on the battery cell during the venting process can be reduced.

[0009] Furthermore, during the venting process of the pressure relief valve assembly, when the electrolyte inside the cell also enters the assembly under pressure, it can flow through the first connecting surface (i.e., the inclined surface) on the bottom wall of the first mounting slot into the first pressure relief hole of the top cover. Then, it flows through the first pressure relief hole of the top cover to the surface of the lower plastic near the top cover, and further into the second pressure relief hole of the lower plastic, finally flowing back into the cell through the second pressure relief hole. This achieves the purpose of returning the electrolyte that has splashed into the pressure relief valve assembly to the cell, preventing the electrolyte from splashing out or overflowing to the outside of the battery through the pressure relief valve assembly.

[0010] In one possible implementation, the lower plastic is further provided with a second mounting groove, the opening of the second mounting groove is located on the surface of the lower plastic near the top cover, and the second pressure relief hole is located on the outer edge of the bottom wall of the second mounting groove and communicates with the second mounting groove;

[0011] Part of the top cover is located in the second mounting groove. The gap area between the top cover and the bottom wall of the second mounting groove, and the gap area between the top cover and the peripheral side wall of the second mounting groove, cooperate to form a flow channel for the electrolyte to pass through. The flow channel is connected between the first pressure relief hole and the second pressure relief hole, and communicates with the first pressure relief hole and the second pressure relief hole.

[0012] In one possible implementation, the second mounting groove includes a second connecting surface that forms at least a portion of the bottom wall of the second mounting groove. The second connecting surface is located between the first pressure relief hole and the second pressure relief hole. In the thickness direction of the top cover assembly, the distance between the second connecting surface and the opening of the second mounting groove gradually decreases from one end toward the second pressure relief hole to the end away from the second pressure relief hole.

[0013] In one possible implementation, the second mounting groove is coaxially arranged with the first mounting groove, the lower plastic includes a first edge and a second edge, the first edge and the second edge are arranged opposite to each other in the width direction of the lower plastic, and the distance between the central axis of the second mounting groove and the first edge is equal to the distance between the central axis of the second mounting groove and the second edge.

[0014] In one possible implementation, the lower plastic includes a lower plastic body and a baffle, at least a portion of the second pressure relief hole is provided in the lower plastic body, one end of the baffle is connected to the surface of the lower plastic away from the top cover, the other end of the baffle extends in a direction away from the top cover, and the baffle is located on the side of the second pressure relief hole away from the second mounting groove.

[0015] In one possible implementation, the lower plastic includes a lower plastic body and a first protrusion, the first protrusion being fixedly connected to the lower plastic body and protruding from the surface of the lower plastic body away from the top cover, and the second pressure relief hole and the second mounting groove being provided in the lower plastic body and the first protrusion.

[0016] The first protrusion is defined as the height at which the first protrusion protrudes from the surface of the lower plastic body away from the top cover. The second protrusion is defined as the height at which the baffle protrudes from the surface of the lower plastic body away from the top cover. The second height is greater than the first height.

[0017] In one possible implementation, the lower plastic body further includes a support portion connected to the surface of the lower plastic body facing away from the top cover and spaced apart from the baffle. The support portion is used to abut against the battery cell. The protrusion height of the baffle relative to the surface of the lower plastic body facing away from the top cover is a second height, and the protrusion height of the support portion relative to the surface of the lower plastic body facing away from the top cover is a third height, wherein the third height is greater than the second height.

[0018] In one possible implementation, the top cover assembly further includes a pressure relief valve assembly located within the first mounting groove. The pressure relief valve assembly includes a pressure plate, an elastic element, a first seal, and a second seal arranged sequentially. The pressure plate is close to the opening of the first mounting groove. The elastic element is elastically connected between the pressure plate and the first seal. The second seal is sealingly connected between the first seal and the bottom wall of the first mounting groove.

[0019] In one possible implementation, the second seal is in line contact with the first seal, and the second seal is in line contact with the bottom wall of the first mounting groove.

[0020] In one possible implementation, the elastic element includes a first connecting portion and a plurality of legs. The first connecting portion abuts against the pressure plate, and the inner edge of the first connecting portion is covered by the pressure plate. The plurality of legs are spaced apart in the circumferential direction of the first connecting portion. One end of each leg is fixedly connected to the first connecting portion, and the other end of each leg abuts against the first sealing member. The legs are capable of moving relative to the first sealing member in the radial direction of the first connecting portion.

[0021] In one possible implementation, the elastic element includes a first connecting portion, a second connecting portion, and a plurality of legs. The first connecting portion abuts against the pressure plate, and the inner edge of the first connecting portion is covered by the pressure plate. The plurality of legs are spaced apart in the circumferential direction of the first connecting portion. One end of each leg is fixedly connected to the outer edge of the first connecting portion, and the other end of each leg is fixedly connected to the inner edge of the second connecting portion. The second connecting portion and the first connecting portion are spaced apart in the thickness direction of the elastic element and abut against the first sealing element. The second connecting portion is movable relative to the first sealing element in the radial direction of the first connecting portion.

[0022] In one possible implementation, the pressure plate includes a pressure plate body and a flange. One end of the flange is connected to the pressure plate body, and the other end of the flange is projected into the pressure plate body along the thickness direction of the pressure plate. The flange is bent relative to the pressure plate body, and the flange and the pressure plate body cooperate to form a first groove. Part of the elastic element is located in the first groove and abuts between the pressure plate body and the flange.

[0023] In one possible implementation, the first mounting groove includes a first groove and a second groove, which are coaxially arranged. The cross-sectional width of the first groove along the thickness direction of the top cover is greater than the cross-sectional width of the second groove along the thickness direction of the top cover. A first stepped surface is formed at the connection between the first groove and the second groove. The pressure plate is located in the first groove and abuts against the first stepped surface. The elastic element is located in the first groove and the second groove. The first sealing element and the second sealing element are both located in the second groove.

[0024] Secondly, this application also provides a battery, the battery including a cell, a housing and a top cover assembly as described above, the top cover assembly being connected to the housing and forming an accommodating space with the housing, the cell being located within the accommodating space.

[0025] Thirdly, this application also provides an electrical device, which includes the battery described above. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the energy storage system provided in an embodiment of this application;

[0027] Figure 2 This is a schematic diagram of a battery structure provided in an embodiment of this application;

[0028] Figure 3This is a schematic diagram of a top cover assembly provided in an embodiment of this application;

[0029] Figure 4 yes Figure 3 The exploded view of the top cover assembly is shown.

[0030] Figure 5a It is along Figure 3 A cross-sectional schematic diagram of a portion of the structure of the top cover assembly obtained by cutting along section line AA as shown;

[0031] Figure 5b It is along Figure 5a A magnified view of region B in the middle;

[0032] Figure 6a yes Figure 3 A schematic diagram of the top cover assembly at one angle;

[0033] Figure 6b yes Figure 3 A schematic diagram of the top cover assembly from another angle;

[0034] Figure 7 It is along Figure 3 Another cross-sectional view of a portion of the top cover assembly obtained by cutting along section line AA;

[0035] Figure 8a yes Figure 3 A schematic diagram of the structure of the lower plastic of the top cover assembly at one angle;

[0036] Figure 8b yes Figure 3 A schematic diagram of the structure of the lower plastic of the top cover assembly from another angle;

[0037] Figure 8c yes Figure 3 A schematic diagram of the structure of the lower plastic of the top cover assembly at another angle;

[0038] Figure 9 yes Figure 3 An exploded view of the pressure relief valve assembly of the top cover assembly shown.

[0039] Figure 10a yes Figure 9 A schematic diagram of the pressure plate of the pressure relief valve assembly at one angle;

[0040] Figure 10b yes Figure 9 A schematic diagram of the pressure plate of the pressure relief valve assembly from another angle;

[0041] Figure 11a yes Figure 9A schematic diagram of the elastic element of the pressure relief valve assembly shown;

[0042] Figure 11b yes Figure 9 Another structural schematic diagram of the elastic element of the pressure relief valve assembly shown;

[0043] Figure 12 This is a schematic diagram of the assembly process of the elastic element and the pressure plate;

[0044] Figure 13a yes Figure 9 A schematic diagram of the structure of the first seal of the pressure relief valve assembly at one angle;

[0045] Figure 13b yes Figure 9 A schematic diagram of the first seal of the pressure relief valve assembly from another angle;

[0046] Figure 14a yes Figure 9 A schematic diagram of the structure of the second seal of the pressure relief valve assembly at one angle;

[0047] Figure 14b yes Figure 9 A schematic diagram of the second seal of the pressure relief valve assembly from another angle;

[0048] Figure 15 yes Figure 3 A schematic diagram of the upper plastic structure of the top cover assembly shown;

[0049] Figure 16 yes Figure 3 The diagram shows a structural schematic of the pole of the top cover assembly.

[0050] Figure label:

[0051] Energy storage system 400, power conversion device 410, first user load 420, second user load 430, electrical equipment 300, battery 200, housing 210, battery cell 220, top cover assembly 100, top cover 10, lower plastic 20, pressure relief valve assembly 30, upper plastic 40, pole 50, explosion-proof valve 60, explosion-proof valve protection plate 70, explosion-proof valve assembly F, first mounting groove 11, first pressure relief hole 12, third edge 13a, fourth edge 13b, first connecting surface 111, first groove 112, second groove 113, first stepped surface 114, second stepped surface 115, top cover body 14, second protrusion 15, first surface 141, second surface 142, first groove 16a, first through hole 16b, first boss 16c, explosion-proof hole 17, first liquid injection. Hole 18, Second pressure relief hole 21, Second mounting groove 22, First edge 23a, Second edge 23b, Second connecting surface 221, Lower plastic body 24, First protrusion 25, Third surface 241, Fourth surface 242, Baffle 26, Support 27, Second groove 28a, Second through hole 28b, Second boss 28c, Second injection hole 29, First height H1, Second height H2, Third height H3, Pressure plate 31, Elastic element 32, First seal 33, Second seal 34, Air outlet 311, Pressure plate body 312, Flanged edge 313, First slot 314, First sub-part 3131, Second sub-part 3132, Third mounting groove 315, Fourth mounting groove 316, First connecting part 321, Support leg 322, Third air passage S3, First sub-air passage S3 1、 Second sub-air passage S32, first connecting end 322a, second connecting end 322b, second connecting part 323, first distance d1, first sealing body 331, barrier wall 332, first surface 3311, second surface 3312, abutting surface 3311a, first air passage S1, second air passage S2, inner ring body 341, outer ring body 342, first thickness T1, second thickness T2, fifth surface 41, sixth surface 42, third through hole 43, second slot 44, first side surface 441, second side surface 442, pole post body 51, pole post base 52, first body 511, second body 512, third body 513, fourth body 514. Detailed Implementation

[0052] For ease of understanding, the terminology used in the embodiments of this application will be explained first.

[0053] And / or: This is simply a way of describing the relationship between related objects. It indicates that there can be three kinds of relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0054] Multiple: refers to two or more.

[0055] Connection: should be interpreted broadly. For example, the connection between A and B can be a direct connection between A and B, or an indirect connection between A and B through an intermediary.

[0056] The specific embodiments of this application will now be clearly described in conjunction with the accompanying drawings. Obviously, the described embodiments are merely a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0057] Embodiments of this application provide a top cover assembly, a battery, and an electrical device.

[0058] Because the energy we need is highly time- and space-dependent, in order to utilize energy rationally and improve energy efficiency, it is necessary to store one form of energy in the same way or by converting it into another, and then release it in a specific energy form according to future application needs. As we all know, the generation of green electricity currently relies heavily on photovoltaic, wind, and hydropower. However, wind and solar energy are generally characterized by strong intermittency and large fluctuations, which can cause grid instability, insufficient power during peak demand periods, and excessive power during off-peak periods. Unstable voltage can also damage the power grid. Therefore, insufficient electricity demand or insufficient grid capacity can lead to the problem of "wind and solar curtailment." Solving these problems requires energy storage. This involves converting electrical energy into other forms of energy through physical or chemical means and storing it, then releasing the stored energy as electricity when needed. Simply put, energy storage is like a large "power bank," storing electrical energy when photovoltaic and wind power are abundant and releasing the stored electricity when needed.

[0059] Taking electrochemical energy storage as an example, the embodiments of this application provide an electrical device 300, which is equipped with a set of chemical batteries. The main purpose is to use the chemical elements in the chemical batteries as energy storage medium. The charging and discharging process is accompanied by the chemical reaction or change of the energy storage medium. Simply put, the electrical energy generated by wind and solar energy is stored in the chemical batteries. When the use of external electrical energy reaches its peak, the stored electricity is released for use, or it is transferred to places where electricity is scarce for use.

[0060] Current energy storage applications are quite widespread, including generation-side energy storage, grid-side energy storage, renewable energy grid-connected energy storage, and user-side energy storage. The corresponding types of electrical equipment (number 300) include:

[0061] Large energy storage containers used in grid-side energy storage scenarios can serve as high-quality active and reactive power regulation power sources in the power grid, enabling load matching of electrical energy in time and space, enhancing the absorption capacity of renewable energy, and playing a significant role in grid system backup, alleviating peak load power supply pressure, and peak shaving and frequency regulation.

[0062] Small and medium-sized energy storage cabinets used in industrial and commercial energy storage scenarios on the user side, and small household energy storage boxes used in residential energy storage scenarios on the user side, mainly operate under the "peak shaving and valley filling" mode. Because there are significant price differences in electricity during peak and off-peak periods based on electricity demand, users typically charge the energy storage cabinet / box during off-peak hours to reduce costs, and then release the electricity from the device during peak hours for use, thus saving on electricity bills. Furthermore, in remote areas and regions prone to natural disasters such as earthquakes and hurricanes, the presence of household energy storage devices effectively provides users with backup power for themselves and the power grid, avoiding the inconvenience caused by frequent power outages due to disasters or other reasons.

[0063] Please see Figure 1 , Figure 1 This is a schematic diagram of the energy storage system 400 provided in an embodiment of this application. This embodiment uses a home energy storage scenario in user-side energy storage as an example for illustration; however, the electrical equipment 300 in this application is not limited to a home energy storage scenario.

[0064] This application provides an energy storage system 400, which includes a power conversion device 410, a first user load 420, a second user load 430, and an electrical appliance 300. The electrical appliance 300 is a small energy storage box that can be wall-mounted on an outdoor wall. Specifically, photovoltaic panels can convert solar energy into electrical energy during periods of low electricity prices, and the electrical appliance 300 stores this electrical energy to supply streetlights and household appliances during peak electricity prices, or to provide power during power outages.

[0065] The electrical device 300 may include, but is not limited to, individual batteries, battery modules, battery packs, and battery systems. When the electrical device 300 includes multiple batteries, the multiple batteries are electrically connected and all are located inside the casing of the electrical device 300, which protects them from interference from the external environment. Exemplarily, the multiple batteries are arranged at intervals. The multiple batteries can be connected in series, in parallel, or a combination of series and parallel connections to achieve greater capacity and power. The embodiments of this application are illustrated using the example of an electrical device 300 including batteries, but it should be understood that the electrical device 300 is not limited thereto.

[0066] Please see Figure 2 , Figure 2This is a schematic diagram of a battery 200 provided in an embodiment of this application.

[0067] For ease of description, the length direction of battery 200 is defined as the X direction, the width direction as the Y direction, and the height direction as the Z direction. The X, Y, and Z directions are all perpendicular to each other.

[0068] Battery 200 may include a top cover assembly 100, a housing 210, and a battery cell 220. The top cover assembly 100 is connected to the housing 210 and forms a receiving space with the housing 210, within which the battery cell 220 is located. Exemplarily, the top cover assembly 100 may be welded to the housing 210. The housing 210 may be made of a metallic material, such as aluminum alloy. Battery 200 may be a cylindrical battery 200 or a prismatic battery 200, etc.

[0069] It should be noted that, Figure 2 The purpose is merely to illustratively describe the connection relationship between the top cover assembly 100, the housing 210, and the battery cell 220, and is not to specifically limit the connection positions, specific structures, or quantities of each device. Furthermore, the structures illustrated in the embodiments of this application do not constitute a specific limitation on the battery 200. In other embodiments of this application, the battery 200 may include components such as... Figure 2 This may involve more or fewer components, or combining certain components, or splitting certain components, or different component arrangements. Figure 2 The components shown can be implemented in hardware, software, or a combination of both.

[0070] Understandably, during battery use, chemical reactions within the cells produce a large amount of gas, which can be released by rupturing the explosion-proof valve assembly in the top cover. However, the explosion-proof valve assembly is a disposable product; its damage significantly impacts the battery's cycle life. Therefore, in addition to the explosion-proof valve assembly, the top cover assembly typically includes a reusable pressure relief valve assembly with less impact on battery life. This valve is used to promptly release gas, preventing gas accumulation within the cells and thus avoiding premature opening of the explosion-proof valve, which would affect the battery's cycle life. However, during the venting process using the pressure relief valve assembly, due to the internal gas pressure, electrolyte can easily splash into the assembly and even overflow onto the outside of the battery.

[0071] Therefore, embodiments of this application provide a top cover assembly 100 that can redirect electrolyte that has splashed into the pressure relief valve assembly 30 back into the battery cell 220, preventing electrolyte from overflowing from the battery 200 through the pressure relief valve assembly 30. The structure of the top cover assembly 100 will be described below using the pressure relief valve assembly 30 as an example of a venting structure. Unless otherwise specified, the improvements made to the top cover assembly 100 to prevent electrolyte overflow can also be applied to other structures, devices, or equipment that require prevention of liquid overflow, and are not strictly limited thereto.

[0072] Please refer to the following: Figure 3 and Figure 4 , Figure 3 This is a schematic diagram of a top cover assembly 100 provided in an embodiment of this application. Figure 4 yes Figure 3 The exploded structural diagram of the top cover assembly 100 shown.

[0073] The top cover assembly 100 may include a top cover 10, a lower plastic component 20, a pressure relief valve assembly 30, an upper plastic component 40, a terminal post 50, an explosion-proof valve 60, and an explosion-proof valve protection plate 70. The lower plastic component 20 and the upper plastic component 40 are sequentially mounted on the top cover 10 along the thickness direction (Z direction in the diagram). The terminal post 50 is mounted on the top cover 10 and insulated from the top cover 10 by the upper plastic component 40 and the lower plastic component 20. The terminal post 50 can serve as an electrode lead-out of the battery 200. The pressure relief valve assembly 30 is connected to the top cover 10 and is spaced apart from the terminal post 50 along the length direction (X direction in the diagram) of the top cover 10. The pressure relief valve assembly 30 is used for pressure relief protection of the battery 200. The explosion-proof valve assembly 60 is connected to the top cover 10 and is spaced apart from the pressure relief valve assembly 30 and the upper plastic component 40 along the length direction of the top cover 10, and is used for pressure relief protection of the battery 200. The explosion-proof valve assembly F may include an explosion-proof valve 60 and an explosion-proof valve protection plate 70. Both the explosion-proof valve 60 and the explosion-proof valve protection plate 70 are connected to explosion-proof holes 17 on the top cover 10 and are sequentially arranged in the thickness direction (Z direction in the diagram) of the top cover 10. The explosion-proof valve protection plate 70 covers the explosion-proof valve 60.

[0074] In the embodiments of this application, the number of terminals 50 can be two. The two terminals 50 are a positive terminal and a negative terminal, respectively. The two terminals 50 are spaced apart along the length of the top cover 10. The number of upper plastic parts 40 can also be two. One upper plastic part 40 is fitted onto the positive terminal. The other upper plastic part 40 is fitted onto the negative terminal. The structure of the top cover assembly 100 will be described below using the assembly of one terminal 50, one upper plastic part 40, the top cover 10, and the lower plastic part 20 as an example. Unless otherwise specified, the description of the structure of one terminal 50 and one upper plastic part 40 below can be applied to other terminals 50 and upper plastic parts 40.

[0075] Please refer to the following: Figure 5a , Figure 5b , Figure 6a and Figure 6b , Figure 5a It is along Figure 3 The diagram shows a cross-sectional view of a portion of the structure of the top cover assembly 100 obtained by cutting along section line AA. Figure 5b It is along Figure 5a A magnified view of region B in the middle. Figure 6a yes Figure 3 The diagram shows a structural schematic of the top cover 10 of the top cover assembly 100 at one angle. Figure 6b yes Figure 3 A structural schematic diagram of the top cover 10 of the top cover assembly 100 from another angle.

[0076] The top cover 10 may be provided with a first mounting groove 11 and a first pressure relief hole 12. The opening of the first mounting groove 11 is located on the surface of the top cover 10 opposite to the battery cell 220. The first mounting groove 11 may be recessed from the surface of the top cover 10 opposite to the battery cell 220 toward the interior of the top cover 10. The first mounting groove 11 is used to mount the pressure relief valve assembly 30. The first pressure relief hole 12 penetrates the bottom wall of the first mounting groove 11 along the thickness direction of the top cover 10. The first pressure relief hole 12 is coaxially arranged with and connected to the first mounting groove 11. The first pressure relief hole 12 may be covered by the pressure relief valve assembly 30. The first pressure relief hole 12 allows gas and electrolyte generated inside the battery cell 220 to pass through.

[0077] The top cover 10 may include a third edge 13a and a fourth edge 13b. The third edge 13a and the fourth edge 13b are disposed opposite each other in the width direction (Y direction shown in the figure) of the top cover 10. The distance between the central axis of the first mounting groove 11 and the third edge 13a is equal to the distance between the center line of the first mounting groove 11 and the fourth edge 13b (within the allowable tolerance range). That is, along the width direction of the top cover 10, the first mounting groove 11 is located at the middle position of the top cover 10 (within the allowable tolerance range).

[0078] The first mounting groove 11 may include a first connecting surface 111. The first connecting surface 111 forms at least a portion of the bottom wall of the first mounting groove 11. The first connecting surface 111 surrounds and connects to the outer edge of the first pressure relief hole 12, and is coaxially arranged with the first pressure relief hole 12. That is, the first connecting surface 111 is annular and surrounds the first pressure relief hole 12. In the thickness direction of the top cover assembly 100, the distance between the first connecting surface 111 and the opening of the first mounting groove 11 gradually decreases from the end connected to the first pressure relief hole 12 towards the end away from the first pressure relief hole 12. That is, the first connecting surface 111 is a slope.

[0079] It is understandable that by setting the bottom wall of the first mounting groove 11 around the first pressure relief hole 12 as a slope, the electrolyte splashed into the first mounting groove 11 can flow into the first pressure relief hole 12 through the slope and then flow back to the cell 220, preventing the electrolyte from splashing out of the battery 200 through the pressure relief valve assembly 30.

[0080] In some other embodiments, in the thickness direction of the top cover assembly 100, the distance between the first connecting surface 111 and the opening of the first mounting groove 11 can remain constant and then gradually decrease from the end connected to the first pressure relief hole 12 to the end away from the first pressure relief hole 12.

[0081] In some other embodiments, the first connecting surface 111 may also form the entire bottom wall of the first mounting groove 11. That is, the first connecting surface 111 is the bottom wall of the first mounting groove 11. In this case, in the thickness direction of the top cover assembly 100, the distance between the first connecting surface 111 and the opening of the first mounting groove 11 gradually decreases from the end connected to the first pressure relief hole 12 towards the end away from the first pressure relief hole 12. Alternatively, in the thickness direction of the top cover assembly 100, the distance between the first connecting surface 111 and the opening of the first mounting groove 11 may remain constant and then gradually decrease from the end connected to the first pressure relief hole 12 towards the end away from the first pressure relief hole 12.

[0082] The embodiments of this application do not limit the proportion of the first connecting surface 111 occupying the bottom wall of the first mounting groove 11, as long as the electrolyte splashed into the first mounting groove 11 can flow into and back to the battery cell 220 through the inclined surface on the bottom wall of the first mounting groove 11.

[0083] In embodiments of this application, the first mounting groove 11 may include a first groove 112 and a second groove 113. The first groove 112 and the second groove 113 are coaxially arranged and connected. The opening of the first groove 112 may be the opening of the first mounting groove 11. The first groove 112 may be used to accommodate the pressure plate 31 and part of the elastic element 32 of the pressure relief valve assembly 30. The bottom wall of the second groove 113 is the bottom wall of the first mounting groove 11. The cross-sectional width of the second groove 113 along the thickness direction of the top cover 10 may be smaller than the cross-sectional width of the first groove 112 along the thickness direction of the top cover 10. The second groove 113 may be used to accommodate the first sealing element 33 and the second sealing element 34, as well as part of the elastic element 32, of the pressure relief valve assembly 30.

[0084] The connection between the first groove 112 and the second groove 113 can form a first stepped surface 114 and a second stepped surface 115. The first stepped surface 114 can be the bottom wall of the first groove 112. The first stepped surface 114 can be parallel to the bottom wall of the first mounting groove 11 and can be used to abut against the pressure plate 31. The second stepped surface 115 can be the inner peripheral wall of the second groove 113. The inner peripheral wall of the second groove 113 is a surface surrounding the central axis of the second groove 113. The second stepped surface 115 can be perpendicular to the first stepped surface 114.

[0085] Understandably, by forming a stepped surface within the first mounting groove 11 of the top cover 10 to support the pressure plate 31, the pressure plate 31 abuts against and is fixed to the stepped surface. When the elastic member 32 is compressed by the pressure of the first sealing member 33, the pressure plate 31 connected to the elastic member 32 can remain stationary, ensuring the connection stability of the pressure relief valve assembly 30. At the same time, the abutment between the pressure plate 31 and the stepped surface also enhances the sealing performance of the pressure relief valve assembly 30.

[0086] In embodiments of this application, the top cover 10 may include a top cover body 14 and a second protrusion 15. The second protrusion 15 is connected to the top cover body 14 and protrudes from the surface of the plastic 20 facing downward relative to the top cover body 14. The second protrusion 15 and the top cover body 14 may be connected to form an integral structure. Exemplarily, the second protrusion 15 and the top cover body 14 may be an integral structure formed by connecting them through methods such as integral molding. Alternatively, the second protrusion 15 and the top cover body 14 may also be an integral structure formed by connecting them through assembly methods such as welding or bonding. It should be noted that the integral structures described below can all be formed by connecting them through assembly methods such as integral molding, welding, or bonding, and will not be described again.

[0087] Please refer to the following: Figure 5a , Figure 6a , Figure 6b and Figure 7 , Figure 7 It is along Figure 3 Another cross-sectional view of a portion of the structure of the top cover assembly 100 obtained by cutting along section line AA.

[0088] The top cover body 14 may include a first surface 141 and a second surface 142. The first surface 141 and the second surface 142 are disposed opposite to each other in the thickness direction (Z direction in the figure) of the top cover body 14. The first surface 141 faces away from the battery cell 220. The second surface 142 faces the battery cell 220. The second surface 142 may be connected to the third surface 241 of the lower plastic 20 and the surface of the electrode base 52 of the electrode post 50 near the electrode post body 51. The second protrusion 15 is connected to the second surface 142 of the top cover body 14 and is located in the second mounting groove 22 of the lower plastic 20.

[0089] The top cover body 14 and the second protrusion 15 may be provided with the first pressure relief hole 12 and the first mounting groove 11 described above. Both the first pressure relief hole 12 and the first mounting groove 11 are coaxially arranged with the second protrusion 15. The first pressure relief hole 12 can penetrate the first surface 141 and the surface of the second protrusion 15 away from the top cover body 14. That is, the first through hole 16b can penetrate the top cover body 14 and the second protrusion 15 along the thickness direction of the top cover 10. The opening of the first mounting groove 11 is located on the first surface 141. The first mounting groove 11 can be recessed from the first surface 141 into the interior of the top cover 10 and the second protrusion 15. The first groove 112 is located within the top cover body 14, and the second groove 113 is located within the second protrusion 15 and a portion of the top cover body 14. In some other embodiments, the first groove 112 can be located within the top cover body 14, the second groove 113 can be located within the second protrusion 15, and the first stepped surface 114 is flush with the second surface 142. Alternatively, the first groove 112 may be located within the top cover body 14 and part of the second protrusion 15, and the second groove 113 may be located within the second protrusion 15.

[0090] Please refer to the following: Figure 6a , Figure 6b and Figure 7 The top cover 10 may have a first groove 16a and a first through hole 16b. The opening of the first groove 16a is located on the surface of the top cover 10 facing the cell 220. That is, the opening of the first groove 16a is located on the second surface 142 of the top cover 10. The first groove 16a may be recessed from the second surface 142 into the interior of the top cover 10. The first groove 16a may be used to accommodate the second boss 28c of the lower plastic 20, a portion of the upper plastic 40, and a portion of the electrode base 52 of the electrode 50. The first through hole 16b may penetrate the top cover 10 along the thickness direction. The first through hole 16b is coaxially arranged with and connected to the first groove 16a. The first through hole 16b may communicate with the third through hole 43 of the upper plastic 40 and the second through hole 28b of the lower plastic 20. The first through hole 16b is used for the electrode 50 to pass through.

[0091] The top cover 10 may have two first grooves 16a, spaced apart along its length (X direction in the diagram). Each first groove 16a can be used to mount a second boss 28c of the lower plastic 20, a portion of the upper plastic 40, and a portion of the electrode base 52 of the electrode 50. The top cover 10 may also have two first through holes 16b, spaced apart along its length and coaxially connected to the two first grooves 16a. One first through hole 16b is for the positive electrode to pass through, and the other is for the negative electrode to pass through.

[0092] In embodiments of this application, the top cover 10 may include a first protrusion 16c. The first protrusion 16c is connected to the first surface 141 of the top cover body 14 and protrudes relative to the first surface 141. The first protrusion 16c and the top cover body 14 can be connected by means such as integral molding to form an integral structure. The first protrusion 16c is located in the second slot 44 of the upper plastic 40. The surface of the first protrusion 16c facing away from the top cover body 14 abuts against the first side 441 of the second slot 44 of the upper plastic 40. In some other embodiments, the top cover 10 may not include the first protrusion 16c, as long as the top cover 10 can be installed in the second slot 44 of the upper plastic 40.

[0093] For example, there may be two first protrusions 16c, which are spaced apart along the length of the top cover 10. Each first protrusion 16c is connected to a second slot 44 on the upper plastic 40.

[0094] The top cover body 14 and the first boss 16c may be provided with the first through hole 16b and the first groove 16a described above. The first through hole 16b can penetrate the second surface 142 and the first boss 16c away from the surface of the top cover body 14. That is, the first through hole 16b can penetrate the top cover body 14 and the first boss 16c along the thickness direction of the top cover 10. The opening of the first groove 16a is located on the second surface 142. The first groove 16a can be formed by recessing from the second surface 142 into the interior of the top cover 10. The bottom wall of the first groove 16a abuts against the second side 442 of the second slot 44 of the upper plastic 40. The bottom wall of the first groove 16a can be located inside the top cover body 14. Alternatively, the bottom wall of the first groove 16a can be located inside the first boss 16c. Alternatively, the bottom wall of the first groove 16a can be flush with the first surface 141. In the embodiments of this application, the depth of the first groove 16a is not limited, as long as the distance between the bottom wall of the first groove 16a and the surface of the first boss 16c away from the top cover body 14 is equal to the distance between the two inner peripheral surfaces of the second slot 44 of the upper plastic 40.

[0095] The top cover 10 may also be provided with an explosion-proof hole 17 and a first injection hole 18. Specifically, along the length direction (X direction in the figure) of the top cover body 14, the explosion-proof hole 17 is located between the first pressure relief hole 12 and the first through hole 16b, and is spaced apart from both the first pressure relief hole 12 and the first through hole 16b. That is, the explosion-proof valve assembly F is spaced apart from the pressure relief valve assembly 30. The explosion-proof hole 17 can penetrate the first surface 141 and the second surface 142. That is, the explosion-proof hole 17 penetrates the top cover body 14 along the thickness direction of the top cover body 14. The explosion-proof hole 17 is used to connect with the explosion-proof valve 60 and the explosion-proof valve protection plate 70.

[0096] Along the length of the top cover body 14, a first injection hole 18 can be disposed between the explosion-proof hole 17 and the first through hole 16b, and located at both ends of the explosion-proof hole 17, respectively, and the first pressure relief hole 12. The first injection hole 18 and the explosion-proof hole 17, the first through hole 16b and the first pressure relief hole 12 are all spaced apart. The first injection hole 18 can penetrate through the first surface 141 and the second surface 142. That is, the first injection hole 18 penetrates the top cover body 14 along its thickness direction. The first injection hole 18 is used to inject electrolyte into the battery cell 220.

[0097] Please refer to the following: Figure 5a , Figure 5b , Figure 7 and Figure 8a , Figure 8a yes Figure 3 A schematic diagram of the structure of the lower plastic 20 of the top cover assembly 100 at an angle.

[0098] The lower plastic 20 is connected to the second surface 142 of the top cover 10. A portion of the lower plastic 20 is located between the upper plastic 40 and the electrode base 52 of the electrode post 50. The lower plastic 20 may be provided with a second pressure relief hole 21. The second pressure relief hole 21 penetrates the lower plastic 20 along its thickness direction. The second pressure relief hole 21 may communicate with the first pressure relief hole 12 of the top cover 10 and is used to allow electrolyte passage. Exemplarily, the second pressure relief hole 21 may be disposed opposite to the first pressure relief hole 12 of the top cover 10 in the thickness direction of the top cover assembly 100. That is, the second pressure relief hole 21 may be directly connected to the first pressure relief hole 12 of the top cover 10. Alternatively, the second pressure relief hole 21 may be offset from the first pressure relief hole 12 of the top cover 10 in the length direction (X direction in the figure) and / or the width direction (Y direction in the figure) of the top cover assembly 100. That is, the second pressure relief hole 21 can be connected to the first pressure relief hole 12 of the top cover 10 in a staggered manner.

[0099] The number of second pressure relief holes 21 can be one or more. When there are multiple second pressure relief holes 21, they can be spaced apart on the lower plastic 20 along the circumferential direction of the second protrusion 15 of the top cover 10. The circumferential direction of the second protrusion 15 is the direction surrounding the central axis of the second protrusion 15. Each second pressure relief hole 21 is offset from and connected to the first pressure relief hole 12.

[0100] Understandably, during battery use, chemical reactions inside the cell produce a large amount of gas. If too much gas accumulates, the battery can easily explode. Therefore, an explosion-proof valve assembly is generally installed in the top cover. The large amount of gas generated inside the cell can break through the explosion-proof valve and be released to the outside of the battery. However, once the explosion-proof valve explodes, it cannot be reused, and the explosion of the explosion-proof valve also greatly reduces the lifespan of the cell.

[0101] Therefore, in the embodiments of this application, by providing a pressure relief valve assembly 30 in the top cover assembly 100, the gas generated by the battery cell 220 can enter the first pressure relief hole 12 of the top cover through the second pressure relief hole 21 of the lower plastic 20, and then enter the interior of the pressure relief valve assembly 30 connected to the first mounting groove 11, and finally be discharged to the outside of the battery 200 through the pressure relief valve assembly 30. That is, by providing a pressure relief valve assembly 30 in the top cover assembly 100, an additional venting path for venting the battery 200 can be added, and the impact on the battery cell 220 during the venting process can be reduced.

[0102] Furthermore, during the venting process using the pressure relief valve assembly 30, due to the internal pressure of the battery cell 220, electrolyte can easily splash into the interior of the pressure relief valve assembly 30, or even splash out or overflow onto the outside of the battery 200 through the pressure relief valve assembly 30. In this case, the electrolyte can flow through the inclined surface on the bottom wall of the first mounting groove 11 into the first pressure relief hole 12 of the top cover 10. Then, it flows through the first pressure relief hole 12 of the top cover 10 into the surface of the lower plastic 20 near the top cover 10, and further into the second pressure relief hole 21 of the lower plastic 20, finally flowing back into the battery cell 220 through the second pressure relief hole 21 of the lower plastic 20. This achieves the purpose of returning the electrolyte that has entered the pressure relief valve assembly 30 into the battery cell 220, preventing the electrolyte from splashing out or overflowing onto the outside of the battery 200 through the pressure relief valve assembly 30. Furthermore, the staggered connection between the second pressure relief hole 21 and the first pressure relief hole 12 can increase the path of the electrolyte of the battery cell 220 into the first mounting groove 11 of the top cover 10, reducing the possibility that the electrolyte will directly splash into the first pressure relief hole 12 of the top cover 10 after entering the second pressure relief hole 21 of the lower plastic 20, and thus enter the first mounting groove 11 of the top cover 10, thereby increasing the difficulty of the electrolyte penetrating into the pressure relief valve assembly 30.

[0103] Please refer to the following: Figure 5a , Figure 5b , Figure 8a and Figure 8b , Figure 8b yes Figure 3 A structural schematic diagram of the lower plastic 20 of the top cover assembly 100 from another angle.

[0104] The lower plastic 20 may be provided with a second mounting groove 22. The opening of the second mounting groove 22 is located on the surface of the lower plastic 20 near the top cover 10. The second mounting groove 22 may be formed by recessing from the surface of the lower plastic 20 near the top cover 10 into the interior of the lower plastic 20. The second mounting groove 22 is coaxially arranged and connected with the first pressure relief hole 12 of the top cover 10, and is also coaxially arranged with the first mounting groove 11 of the top cover 10. The second mounting groove 22 can be used to accommodate the second protrusion 15 of the top cover 10. And there is a gap between the inner wall of the second mounting groove 22 and the second protrusion 15 of the top cover 10. The inner wall of the second mounting groove 22 includes the bottom wall and the inner peripheral wall of the second mounting groove 22. The inner peripheral wall of the second mounting groove 22 is the inner surface surrounding the central axis of the second mounting groove 22. Specifically, there is a gap between the bottom wall of the second mounting groove 22 and the surface of the first protrusion 25 of the lower plastic 20 facing away from the top cover body 14. There is a gap between the inner peripheral wall of the second mounting groove 22 and the outer peripheral surface of the first protrusion 25 of the lower plastic 20. The outer peripheral surface of the first protrusion 25 of the lower plastic 20 is the outer surface surrounding the central axis of the first protrusion 25. These gap areas cooperate to form a flow channel for the electrolyte to pass through.

[0105] The lower plastic 20 may include a first edge 23a and a second edge 23b. The first edge 23a and the second edge 23b are disposed opposite each other in the width direction (Y direction in the figure) of the lower plastic 20. The distance between the central axis of the second mounting groove 22 and the first edge 23a is equal to the distance between the central axis of the second mounting groove 22 and the second edge 23b (within the allowable tolerance range). That is, along the width direction of the lower plastic 20, the second mounting groove 22 is located at the middle position of the lower plastic 20 (within the allowable tolerance range).

[0106] Understandably, during the charging and discharging process of a battery, the surface of the battery electrodes (such as the anode and cathode) may experience areas lacking electrolyte due to uneven electrolyte flow, forming dry zones. Among these, the electrodes located on the inner ring of the cell are relatively more difficult to rewet with the electrolyte from the outer ring compared to the outer ring of the cell.

[0107] Therefore, in the embodiments of this application, the first mounting groove 11 of the top cover 10 is located at the middle position in the width direction of the top cover 10, and the second mounting groove 22 of the lower plastic 20 is located at the middle position in the width direction of the lower plastic 20, so that the second pressure relief hole 21 corresponds to the middle inner ring position of the battery cell 220, thereby redistributing the electrolyte collected from the top cover 10 and the lower plastic 20 to the middle inner ring position of the battery cell 220, improving the rewetting effect of the electrode at the middle inner ring position of the battery cell 220.

[0108] The outer edge of the bottom wall of the second mounting groove 22 may be provided with the second pressure relief hole 21 described above. The second pressure relief hole 21 is connected to the second mounting groove 22. That is, a portion of the outer edge of the second pressure relief hole 21 is connected to a portion of the outer edge of the bottom wall of the second mounting groove 22. The second pressure relief hole 21 and the first pressure relief hole 12 of the top cover 10 are connected by a flow channel formed by the gap between the second mounting groove 22 and the second protrusion 15 of the top cover 10. When there are multiple second pressure relief holes 21, the multiple second pressure relief holes 21 can be spaced apart along the circumferential direction of the second mounting groove 22. The circumferential direction of the second mounting groove 22 is the direction around the central axis of the second mounting groove 22.

[0109] In some other embodiments, the outer edge of the second pressure relief hole 21 can be connected to the inner edge of the bottom wall of the second mounting groove 22. That is, the second pressure relief hole 21 penetrates the bottom wall of the second mounting groove 22 along the thickness direction of the lower plastic 20. Furthermore, the central axis of the second pressure relief hole 21 is spaced apart from the central axis of the second mounting groove 22, which also allows the second pressure relief hole 21 to be misaligned and connected with the first pressure relief hole 12 of the top cover 10.

[0110] It is understandable that by setting the second pressure relief hole 21 of the lower plastic 20 on the outer edge of the bottom wall of the second mounting groove 22, and by coaxially aligning the first pressure relief hole 12 of the top cover 10 with the first mounting groove 11, a staggered arrangement of the second pressure relief hole 21 of the lower plastic 20 and the first pressure relief hole 12 of the top cover 10 is achieved. Furthermore, the flow channel between the second mounting groove 22 of the lower plastic 20 and the second protrusion 15 of the top cover 10 enables communication between the second pressure relief hole 21 of the lower plastic 20 and the first pressure relief hole 12 of the top cover 10. This staggered communication arrangement ensures that the gas generated by the cell 220 can be smoothly discharged to the outside of the battery 200, while increasing the path for the electrolyte of the cell 220 to enter the first mounting groove 11 of the top cover 10, reducing the possibility of electrolyte entering the pressure relief valve assembly 30. In addition, the gap between the second mounting groove 22 of the lower plastic 20 and the second protrusion 15 of the top cover 10 can serve as a buffer space or a liquid storage space, so that the electrolyte splashed into the second mounting groove 22 of the lower plastic 20 needs to accumulate to a certain amount before it can enter the first mounting groove 11 of the top cover 10 through the first pressure relief hole 12, which further increases the difficulty of electrolyte penetrating into the pressure relief valve assembly 30.

[0111] The second mounting groove 22 may further include a second connecting surface 221. The second connecting surface 221 forms at least a portion of the bottom wall of the second mounting groove 22. The second connecting surface 221 is located between the second pressure relief hole 21 and the first pressure relief hole 12 of the top cover 10. In the thickness direction of the top cover assembly 100, the distance between the second connecting surface 221 and the opening of the second mounting groove 22 gradually decreases from the end facing the second pressure relief hole 21 to the end away from the second pressure relief hole 21. That is, the second connecting surface 221 is an inclined surface.

[0112] In some other embodiments, in the thickness direction of the top cover assembly 100, the distance between the second connecting surface 221 and the opening of the second mounting groove 22 may remain constant and then gradually decrease from the end toward the second pressure relief hole 21 to the end away from the second pressure relief hole 21.

[0113] In some other embodiments, the second connecting surface 221 may form the entire bottom wall of the second mounting groove 22. That is, the second connecting surface 221 is the bottom wall of the second mounting groove 22. In this case, in the thickness direction of the top cover assembly 100, the distance between the second connecting surface 221 and the opening of the second mounting groove 22 gradually decreases from the end facing the second pressure relief hole 21 to the end away from the second pressure relief hole 21. Alternatively, in the thickness direction of the top cover assembly 100, the distance between the second connecting surface 221 and the opening of the second mounting groove 22 may remain constant and then gradually decrease from the end facing the second pressure relief hole 21 to the end away from the second pressure relief hole 21.

[0114] The embodiments of this application do not limit the proportion of the second connecting surface 221 occupying the second mounting groove 22, as long as the electrolyte splashed into the second mounting groove 22 can flow into and back to the battery cell 220 through the inclined surface on the bottom wall of the second mounting groove 22.

[0115] Understandably, when the electrolyte enters the first mounting groove 11 of the top cover 10, it can flow through the inclined surface on the bottom wall of the first mounting groove 11 into the first pressure relief hole 12 of the top cover 10. Then, it flows through the first pressure relief hole 12 into the second mounting groove 22 of the lower plastic 20, and then through the inclined surface on the bottom wall of the second mounting groove 22 into the second pressure relief hole 21 of the lower plastic 20, finally flowing back into the battery cell 220. The inclined surfaces on the bottom walls of both the first mounting groove 11 and the second mounting groove 22 of the lower plastic 20 allow the electrolyte splashed into these grooves to flow back into the battery cell 220 more easily, while also increasing the electrolyte flow speed and efficiency.

[0116] In one possible application scenario, please refer to the relevant documentation. Figure 5a , Figure 5b and Figure 8bThe second pressure relief hole 21 is located at the outer edge of the bottom wall of the second mounting groove 22 and communicates with the second mounting groove 22. There can be four second pressure relief holes 21. The four second pressure relief holes 21 can be spaced apart along the circumferential direction of the second mounting groove 22. The four second pressure relief holes 21 can be located at four equal division points along the circumferential direction of the second mounting groove 22. The second connecting surface 221 forms part of the bottom wall of the second mounting groove 22. The second connecting surface 221 is annular. The outer edge of the second connecting surface 221 is the outer edge of the bottom wall of the second mounting groove 22. In the thickness direction of the top cover assembly 100, the distance between the second connecting surface 221 and the opening of the second mounting groove 22 gradually decreases from the end facing the second pressure relief hole 21 towards the end away from the second pressure relief hole 21. The distance between the bottom wall of the second mounting groove 22 and the opening of the second mounting groove 22 remains constant and then gradually increases from the direction near the central axis of the second mounting groove 22 towards the direction away from the central axis of the second mounting groove 22. That is, the area of ​​the bottom wall of the second mounting groove 22 near its central axis is a plane, and the position of this plane corresponds to the opening of the first pressure relief hole 12 of the top cover 10.

[0117] In this application scenario, when the electrolyte of the battery cell 220 splashes into the second mounting groove 22 of the lower plastic 20, the electrolyte will flow through the inclined surface on the bottom wall of the second mounting groove 22 into the second pressure relief hole 21 located at the outer edge of the bottom wall of the second mounting groove 22, and then flow back to the battery cell 220, realizing the return of electrolyte.

[0118] Please refer to the embodiments in this application. Figure 5b , Figure 8a , Figure 8b and Figure 8c , Figure 8c yes Figure 3 The diagram shows a structural schematic of the lower plastic 20 of the top cover assembly 100 at another angle.

[0119] The lower plastic 20 may include a lower plastic body 24 and a first protrusion 25. The first protrusion 25 is fixedly connected to the lower plastic body 24 and protrudes from the surface of the lower plastic body 24 away from the top cover 10. The first protrusion 25 and the lower plastic body 24 can be connected by means such as integral molding to form an integral structure.

[0120] The lower plastic body 24 may include a third surface 241 and a fourth surface 242. The third surface 241 and the fourth surface 242 are disposed opposite to each other in the thickness direction (Z direction in the figure) of the lower plastic body 24. The third surface 241 faces away from the battery cell 220. The fourth surface 242 faces the battery cell 220. The third surface 241 is connected to the second surface 142 of the top cover 10. The lower plastic body 24 can be a one-piece structure. In some other embodiments, the lower plastic body 24 can also be a split structure. Specifically, the lower plastic body 24 may include a first part and a second part. The first part and the second part are arranged sequentially in the length direction (X direction in the figure) of the lower plastic body 24. The first part and the second part are detachably connected.

[0121] The first protrusion 25 is connected to the fourth surface 242 of the lower plastic body 24. In the thickness direction of the lower plastic 20 (Z direction in the figure), the protrusion height of the first protrusion 25 relative to the fourth surface 242 is a first height H1.

[0122] The lower plastic body 24 and the first protrusion 25 may be provided with the second pressure relief hole 21 and the second mounting groove 22 described above. The second pressure relief hole 21 can penetrate the third surface 241 and the fourth surface 242 of the lower plastic body 24, and penetrate the side wall of the first protrusion 25 along the thickness direction of the lower plastic 20. The opening of the second mounting groove 22 is located on the third surface 241. The second mounting groove 22 can be recessed from the third surface 241 into the interior of the lower plastic body 24 and the first protrusion 25. The second mounting groove 22 is coaxially arranged with the first protrusion 25.

[0123] The lower plastic body 20 may also include a baffle 26. One end of the baffle 26 is connected to the fourth surface 242 of the lower plastic body 24, and the other end extends away from the top cover 10. The baffle 26 is continuously arranged around the first protrusion 25 in the circumferential direction and is spaced apart from the first protrusion 25. That is, the baffle 26 is annular and surrounds the first protrusion 25. The circumferential direction of the first protrusion 25 is the direction around the central axis of the first protrusion 25. The baffle 26 is located on the side of the second pressure relief hole 21 away from the second mounting groove 22. In the thickness direction of the lower plastic body 20, the protrusion height of the baffle 26 relative to the fourth surface 242 is a second height H2. The second height H2 of the baffle 26 is greater than the first height H1 of the first protrusion 25. The baffle 26 and the lower plastic body 24 can be connected by means such as integral molding to form an integral structure.

[0124] In some other embodiments, the baffle 26 may be located on the side of the second pressure relief hole 21 away from the second mounting groove 22, and may be intermittently arranged around the first protrusion 25 in the circumferential direction.

[0125] Understandably, placing a baffle 26 on the side of the lower plastic 20 away from the second pressure relief hole 21 away from the second mounting groove 22 can reduce the shaking of the battery cell 220, reduce the possibility of electrolyte splashing into the second mounting groove 22 of the lower plastic 20, and thus reduce the risk of electrolyte overflow from the battery 200. Furthermore, setting the height of the baffle 26 to be greater than the height of the first protrusion 25 ensures that when the electrolyte in the second mounting groove 22 flows into the battery cell 220 through the second pressure relief hole 21, it can be blocked by the baffle 26, thereby directing the electrolyte vertically into a predetermined position within the battery cell 220, that is, into the inner middle ring position of the battery cell 220.

[0126] The lower plastic body 20 may further include a support portion 27. The support portion 27 is connected to the fourth surface 242 of the lower plastic body 24 and is spaced apart from the baffle 26. In the thickness direction of the lower plastic body 20, the protrusion height of the support portion 27 relative to the fourth surface 242 is a third height H3. The third height H3 of the support portion 27 is greater than the second height H2 of the baffle 26. The support portion 27 can be used to abut against the battery cell 220 and support the battery cell 220, preventing the battery cell 220 from directly contacting the top cover 10 and causing a short circuit.

[0127] The number of support portions 27 can be one or more. When there are multiple support portions 27, the positions of the multiple support portions 27 are different, and the structures can be the same, similar, or different. For example, the number of support portions 27 is three. In the length direction of the lower plastic 20, two of the support portions 27 are located at both ends of the lower plastic 20, and a third support portion 27 is provided on the lower plastic 20 at a position corresponding to the explosion-proof hole 17 of the top cover 10.

[0128] It is understandable that setting the height of the support 27 to be greater than the height of the baffle 26 can ensure that the baffle 26 does not directly contact the battery cell 220, but has a certain distance from the battery cell 220, thereby reducing the possibility of electrolyte in the battery cell 220 entering the lower plastic 20.

[0129] The lower plastic body 20 may also be provided with a second injection hole 29. Along the length direction of the lower plastic body 20 (X direction in the diagram), the second injection hole 29 may be disposed between the support portion 27 and the second through hole 28b, and located at both ends of the support portion 27, respectively, along with the second mounting groove 22. The support portion 27 is located in the lower plastic body 20 at the position corresponding to the explosion-proof hole 17 of the top cover 10. The second injection hole 29 is spaced apart from the support portion 27, the second mounting groove 22, and the second through hole 28b. The second injection hole 29 may penetrate the third surface 241 and the fourth surface 242. That is, the second injection hole 29 penetrates the lower plastic body 24 along its thickness direction. The second injection hole 29 can be used to communicate with the first injection hole 18 of the top cover 10 and to inject electrolyte into the battery cell 220.

[0130] Please refer to the following: Figure 7 , Figure 8a , Figure 8b and Figure 8c The lower plastic 20 may be provided with a second groove 28a and a second through hole 28b. The opening of the second groove 28a is located on the surface of the lower plastic 20 opposite to the top cover 10. That is, the opening of the second groove 28a is located on the fourth surface 242. The second groove 28a may be formed by recessing into the interior of the lower plastic 20 from the fourth surface 242. The second groove 28a may be used to install the pole base 52 of the pole 50. The second through hole 28b is coaxially arranged with and connected to the second groove 28a. The second through hole 28b may penetrate the third surface 241 and the bottom wall of the second groove 28a along the thickness direction of the lower plastic 20. That is, one end of the second through hole 28b is located on the third surface 241, and the other end is located on the bottom wall of the second groove 28a. The second through hole 28b is connected to the first through hole 16b of the top cover 10. The second through hole 28b may be used for the pole 50 to pass through and to accommodate the fourth body 514 of the pole 50. The inner surface of the second through hole 28b can be spaced apart from the outer peripheral surface of the fourth body 514 of the pole post 50. The outer peripheral surface of the fourth body 514 of the pole post 50 is the outer surface surrounding the central axis of the fourth body 514. The inner surface of the second through hole 28b is the inner surface surrounding the central axis of the second through hole 28b.

[0131] There can be two second grooves 28a, spaced apart along the length of the lower plastic 20. Each second groove 28a can be used to mount the electrode base 52 of one electrode post 50. There can also be two second through holes 28b, spaced apart along the length of the lower plastic 20, and coaxially connected to and communicating with the two second grooves 28a respectively. One second through hole 28b is used for the positive electrode post to pass through. The other second through hole 16b is used for the negative electrode post to pass through.

[0132] In embodiments of this application, the lower plastic 20 may include a second boss 28c. The second boss 28c is connected to the third surface 241 of the lower plastic body 24 and protrudes relative to the third surface 241. The second boss 28c and the lower plastic body 24 can be connected by means such as integral molding to form an integral structure. The second boss 28c is located in the first groove 16a of the top cover 10. The second boss 28c is separated from the bottom wall of the first groove 16a of the top cover 10 by the upper plastic 40. The surface of the second boss 28c facing away from the top cover body 14 abuts against the sixth surface 42 of the upper plastic 40. The connection between the second boss 28c of the lower plastic 20 and the first groove 16a of the top cover 10 can help align and connect the lower plastic 20 and the top cover 10, improving the assembly efficiency of the top cover assembly 100 and the battery 200.

[0133] For example, there may be two second protrusions 28c, which are spaced apart along the length of the lower plastic 20. Each second protrusion 28c is located within a first groove 16a of a top cover 10.

[0134] The lower plastic body 24 and the second boss 28c may be provided with the second through hole 28b and the second groove 28a described above. The opening of the second groove 28a may be located on the fourth surface 242. The second groove 28a may be recessed into the lower plastic 20 from the fourth surface 242. The bottom wall of the second groove 28a may be located within the lower plastic body 24, and the second through hole 28b may penetrate the second boss 28c and at least a portion of the lower plastic body 24 along the thickness direction of the lower plastic 20. Alternatively, the bottom wall of the second groove 28a may be located within the second boss 28c, and the second through hole 28b may penetrate a portion of the second boss 28c along the thickness direction of the lower plastic 20. Alternatively, the bottom wall of the second groove 28a may be flush with the third surface 241, and the second through hole 28b may penetrate the second boss 28c along the thickness direction of the lower plastic 20.

[0135] Please refer to the following: Figure 5a , Figure 5b and Figure 9 , Figure 9 yes Figure 3 An exploded view of the pressure relief valve assembly 30 of the top cover assembly 100 shown.

[0136] The top cover assembly 100 may further include a pressure relief valve assembly 30. The pressure relief valve assembly 30 is located within the first mounting groove 11 of the top cover 10. The pressure relief valve assembly 30 may include a pressure plate 31, an elastic element 32, a first seal 33, and a second seal 34 arranged sequentially. The pressure plate 31 is located near the opening of the first mounting groove 11 of the top cover 10. The elastic element 32 is elastically connected between the pressure plate 31 and the first seal 33. The second seal 34 is connected between the first seal 33 and the bottom wall of the first mounting groove 11 of the top cover 10.

[0137] By setting a pressure relief valve assembly 30 in the top cover assembly 100, a small amount of gas generated inside the cell 220 can be discharged to the outside of the battery 200, preventing a small amount of gas from failing to break through the explosion-proof valve 60 and accumulating inside the battery 200, which could cause the battery 200 to bulge.

[0138] Please refer to the following: Figure 5a , Figure 5b , Figure 10a and Figure 10b , Figure 10a yes Figure 9 The diagram shows a structural schematic of the pressure plate 31 of the pressure relief valve assembly 30 at one angle. Figure 10b yes Figure 9A schematic diagram of the pressure plate 31 of the pressure relief valve assembly 30 from another angle.

[0139] The pressure plate 31 may be provided with an air outlet 311. The air outlet 311 extends through the pressure plate 31 along its thickness direction (Z direction in the figure). The air outlet 311 is used to connect the interior and exterior of the pressure relief valve assembly 30 and to allow gas generated inside the power core 220 to pass through.

[0140] Specifically, the pressure plate 31 may include a pressure plate body 312 and a flange 313. The pressure plate body 312 is located within the first groove 112 of the first mounting groove 11 of the top cover 10. The surface of the pressure plate body 312 facing the elastic member 32 can abut against the first stepped surface 114 of the top cover 10 and is spaced apart from the surface of the first sealing member 33 facing the pressure plate 31. The pressure plate body 312 is provided with the vent 311 described above. The vent 311 penetrates the pressure plate body 312 along its thickness direction (Z direction in the figure).

[0141] The flange 313 is located on the side of the pressure plate body 312 facing the elastic member 32. One end of the flange 313 is connected to the outer edge of the vent 311. The other end of the flange 313 is projected into the pressure plate body 312 along the thickness direction of the pressure plate 31. That is, the flange 313 is bent relative to the pressure plate body 312. The flange 313 and the pressure plate body 312 cooperate to form a first slot 314. The first slot 314 is used to install part of the elastic member 32.

[0142] The flange 313 may include a first sub-part 3131 and a second sub-part 3132. The first sub-part 3131 is bent and connected between the pressure plate body 312 and the second sub-part 3132. The first sub-part 3131 and the second sub-part 3132 may be coaxial and both protrude from the surface of the pressure plate body 312 toward the elastic member 32. Specifically, the first sub-part 3131 is arranged around the outer edge of the vent 311 and may be arranged substantially perpendicular to the pressure plate body 312. That is, the first sub-part 3131 is annular and surrounds the vent 311. The second sub-part 3132 is connected to the end of the first sub-part 3131 away from the vent 311 and may be arranged substantially parallel to the pressure plate body 312. The second sub-part 3132 may be annular.

[0143] The first sub-part 3131 and the second sub-part 3132 of the flange 313 cooperate with the pressure plate body 312 to form a first slot 314. The surface of the first sub-part 3131 facing away from the vent 311 forms the bottom wall of the first slot 314. The surface of the second sub-part 3132 facing the pressure plate body 312 and the surface of the pressure plate body 312 facing the elastic member 32 cooperate to form the two side walls of the first slot 314. The pressure plate body 312 and the first sub-parts 3131 and 3132 of the flange 313 can be connected by means such as integral molding to form an integral structure.

[0144] It is understandable that by setting a flange 313 on the pressure plate 31 and forming a first slot 314 on the pressure plate 31, the elastic member 32 can be snapped into this slot, thereby achieving a fixed connection between the elastic member 32 and the pressure plate 31 and enhancing the connection stability between the elastic member 32 and the pressure plate 31.

[0145] The pressure plate 31 may be provided with a third mounting groove 315. Specifically, the third mounting groove 315 is located on the pressure plate body 312. The opening of the third mounting groove 315 is located on the surface of the pressure plate body 312 facing the elastic member 32. The third mounting groove 315 is recessed from the surface of the pressure plate body 312 facing the elastic member 32 into the interior of the pressure plate body 312. The third mounting groove 315 is coaxially arranged with the vent 311 and the flange 313. The third mounting groove 315 communicates with the first retaining groove 314. A portion of the bottom wall of the third mounting groove 315 and the surface of the second sub-part 3132 facing the pressure plate body 312 can cooperate to form the side wall of the first retaining groove 314. The third mounting groove 315 can be used to mount part of the elastic member 32 and accommodate part of the first connecting portion 321 of the elastic member 32. The depth of the third mounting groove 315 may be equal to the height of the first sub-part 3131 along the thickness direction of the pressure plate 31.

[0146] In some other embodiments, the depth of the third mounting groove 315 may be greater than the height of the first sub-part 3131 along the thickness direction of the pressure plate 31. Alternatively, the depth of the third mounting groove 315 may be less than the height of the first sub-part 3131 along the thickness direction of the pressure plate 31.

[0147] Understandably, by providing a third mounting groove 315 on the pressure plate 31, the thickness of the pressure plate 31 can be reduced while ensuring its strength. Furthermore, since the third mounting groove 315 can also accommodate part of the elastic element 32, during the assembly of the pressure relief valve assembly 30, the third mounting groove 315 can limit the elastic element 32, making it easier and more convenient for the pressure plate 31 to bend to form a flange 313 and for the flange 313 to be fixed to the elastic element 32.

[0148] The pressure plate 31 may also be provided with a fourth mounting groove 316. The opening of the fourth mounting groove 316 is located on the surface of the pressure plate body 312 opposite to the elastic member 32. The fourth mounting groove 316 is recessed from the surface of the pressure plate body 312 opposite to the elastic member 32 into the interior of the pressure plate body 312. The fourth mounting groove 316 is coaxially arranged with and communicates with the vent 311. The fourth mounting groove 316 is used to mount the pressure member.

[0149] Understandably, during the assembly of battery 200, placing a weighted component on the fourth mounting slot 316 of pressure plate 31 allows pressure plate 31 to remain connected to the first step surface 114 of top cover 10, thus facilitating the setting of the opening threshold of pressure relief valve assembly 30. For example, placing a 0.4kg weighted component on the fourth mounting slot 316 of pressure plate 31, connecting pressure plate 31 to top cover 10, sets the preset opening threshold of pressure relief valve assembly 30 to 0.2MPa. Changing the weight of the weighted component correspondingly changes the opening threshold of pressure relief valve assembly 30. The preset threshold is the air pressure value required to open pressure relief valve assembly 30.

[0150] Please refer to the following: Figure 5a , Figure 5b and Figure 11a , Figure 11a yes Figure 9 A schematic diagram of the elastic element 32 of the pressure relief valve assembly 30 shown.

[0151] The elastic element 32 elastically abuts against the pressure plate 31 and the first sealing element 33, and is located within the first groove 112 and the second groove 113 of the first mounting groove 11 of the top cover 10. The elastic element 32 may include a first connecting portion 321 and a plurality of support legs 322. The plurality of support legs 322 are spaced apart in the circumferential direction of the first connecting portion 321. The circumferential direction of the first connecting portion 321 is the direction around the central axis of the first connecting portion 321. The plurality of support legs 322 and the first connecting portion 321 can be connected to form an integral structure by means such as integral molding. The elastic element 32 may be made of a highly elastic material. For example, the elastic element 32 may be made of 60Si2Mn material. Each 60Si2Mn molecule consists of 60 Si atoms and 2 Mn atoms.

[0152] The first connecting portion 321 may be provided with a second sub-air passage S32. The second sub-air passage S32 extends through the first connecting portion 321 along its thickness direction (Z direction in the figure) and communicates with the air outlet 311 of the pressure plate 31. The second sub-air passage S32 can be used to allow gas to pass through the power supply core 220. The first connecting portion 321 may include an inner edge and an outer edge. The inner edge of the first connecting portion 321 is the outer edge of the second sub-air passage S32. The outer edge of the first connecting portion 321 is away from the second sub-air passage S32. The first connecting portion 321 abuts against the pressure plate 31 and is located in the first slot 314 of the pressure plate 31. The inner edge of the first connecting portion 321 is covered by the pressure plate 31. The thickness of the first connecting portion 321 along the thickness direction (Z direction in the figure) of the elastic member 32 may be equal to the height of the first sub-part 3131 along the thickness direction of the pressure plate 31, or it may be equal to the distance between the two side walls of the first slot 314. Specifically, the surface of the first connecting portion 321 facing the first seal 33 and the surface facing away from the first seal 33 respectively abut against the two side walls of the first slot 314. The inner circumferential surface of the first connecting portion 321 abuts against the bottom wall of the first slot 314. The inner circumferential surface of the first connecting portion 321 is the inner surface surrounding the central axis of the first connecting portion 321, and is also the inner wall of the second sub-air passage S32. That is, the elastic member 32 abuts between the pressure plate body 312 and the flange 313.

[0153] Each leg 322 may include a first connecting end 322a and a second connecting end 322b. The first connecting end 322a of the leg 322 is fixedly connected to the outer edge of the first connecting portion 321. The second connecting end 322b of the leg 322 abuts against the first surface 3311 of the first seal 33 and is spaced apart from the retaining wall 332 of the first seal 33. The second connecting end 322b of the leg 322 is movable relative to the first surface 3311 of the first seal 33 in the radial direction of the first connecting portion 321. Specifically, when the elastic member 32 is compressed by the first seal 33, the second connecting end 322b of the leg 322 moves from the central axis of the second connecting portion 323 toward the retaining wall 332 of the first seal 33, causing the thickness (i.e., height) of the elastic member 32 in the thickness direction of the top cover assembly 100 to decrease.

[0154] The second connecting end 322b of the support leg 322 can be in line contact with the first surface 3311 of the first seal 33. Exemplarily, the second connecting end 322b of the support leg 322 is curved upwards relative to the first surface 3311 of the first seal 33 from the first seal 33 toward the elastic member 32. The second connecting end 322b of the support leg 322 can be an arc-shaped structure. Furthermore, designing the second connecting end 322b of the support leg 322 as an arc portion can prevent the elastic member 32 from scratching the first seal 33 during movement, thus avoiding damage to the surface of the first seal 33 and affecting the rebound effect of the elastic member 32.

[0155] It is understandable that by making the second connecting end 322b of the support leg 322 form a line contact with the first seal 33, the elastic member 32 and the first seal 33 can form a line contact, thereby reducing the difficulty of the support leg 322 moving when the elastic member 32 is under force, and making it easier for the second connecting end 322b of the support leg 322 to move in the radial direction of the first connecting part 321.

[0156] Furthermore, the first connecting portion 321 of the elastic element 32 is installed in the first slot 314 of the pressure plate 31, and the second connecting end 322b of the support leg 322 is movable relative to the first sealing element 33. This ensures that when the elastic element 32 is subjected to pressure inside the battery 200, the height of the elastic element 32 can be reduced by moving the second connecting end 322b of the support leg 322, while the first connecting portion 321 of the elastic element 32 connected to the pressure plate 31 is fixed in the first slot 314 and will not move, thus ensuring the stability of the pressure relief valve assembly 30 during the venting and pressure relief process.

[0157] Please refer to the embodiments in this application. Figure 5a , Figure 5b and Figure 11b , Figure 11b yes Figure 9 Another structural schematic diagram of the elastic element 32 of the pressure relief valve assembly 30 shown.

[0158] The elastic member 32 may further include a second connecting portion 323. The second connecting portion 323 may be annular. The inner edge of the second connecting portion 323 is connected to the second connecting end 322b of the support leg 322. The second connecting portion 323 and the first connecting portion 321 are spaced apart in the thickness direction of the elastic member 32 and are located in the second groove 113 of the first mounting groove 11 of the top cover 10. The second connecting portion 323 abuts against the first surface 3311 of the first sealing member 33 and is movable relative to the first surface 3311 of the first sealing member 33 in the radial direction of the first connecting portion 321. Specifically, when the elastic member 32 is compressed by the first sealing member 33, the second connecting portion 323 moves from the central axis of the second connecting portion 323 toward the retaining wall 332 of the first sealing member 33. That is, when the elastic member 32 is compressed by the first sealing member 33, the cross-sectional width of the second connecting portion 323 gradually increases along the thickness direction of the elastic member 32. This causes the second connecting end 322b of the support leg 322 to move from the central axis of the second connecting part 323 toward the barrier 332 of the first sealing member 33, thereby reducing the thickness (i.e., height) of the elastic member 32 along the thickness direction of the top cover assembly 100.

[0159] The second connecting portion 323 and the first surface 3311 of the first sealing member 33 can be in line contact. For example, the second connecting portion 323 is raised relative to the first surface 3311 of the first sealing member 33 from the first sealing member 33 toward the elastic member 32. Forming a line contact between the second connecting portion 323 and the first sealing member 33 reduces the difficulty of movement of the second connecting portion 323 when the elastic member 32 is under force, facilitating movement of the second connecting portion 323 along the radial direction of the first connecting portion 321. One end of the second connecting portion 323 away from the second connecting end 322b of the support leg 322 can be an arc-shaped structure. Designing the second connecting portion 323 as an arc portion avoids scratching the first sealing member 33 when the elastic member 32 moves, preventing surface damage to the first sealing member 33 and thus affecting the rebound effect of the elastic member 32.

[0160] It is understandable that by setting the second connecting part 323, the second connecting ends 322b of multiple legs 322 can be connected together, so that when the elastic member 32 is subjected to pressure in the cell 220, the second connecting part 323 moves relative to the first sealing member 33 with more uniform force, making the pressure relief valve assembly 30 more stable.

[0161] In embodiments of this application, the elastic member 32 may be provided with a third air passage S3. The third air passage S3 may include a first sub-air passage S31 and the second sub-air passage S32 described above. The first sub-air passage S31 is composed of a gap region between multiple adjacent support legs 322. The first sub-air passage S31 and the second sub-air passage S32 are connected by a space formed by a first connecting portion 321, a second connecting portion 323, and the multiple support legs 322. The third air passage S3 is used for the passage of gas generated within the power supply core 220.

[0162] It is understandable that by setting a third air passage S3 in the elastic member 32, and connecting the first sub-air passage S31 in the third air passage S3 with the first air passage S1 between the first sealing member 33 and the second step surface 115 of the top cover 10, and connecting the second sub-air passage S32 in the third air passage S3 with the air outlet 311 of the pressure plate 31, the third air passage S3 can be connected between the second air passage S2 and the air outlet 311, so that when the pressure relief valve assembly 30 is venting, the gas generated by the battery cell 220 can be normally discharged to the outside of the pressure relief valve assembly 30.

[0163] Please see Figure 12 , Figure 12 This is a schematic diagram of the assembly process of the elastic element 32 and the pressure plate 31. In the embodiments of this application, the assembly process of the elastic element 32 and the pressure plate 31 may include at least the following steps:

[0164] First, a third mounting groove 315 is formed on the surface of the pressure plate 31 facing the cell 220.

[0165] Secondly, the pressure plate 31 area around the central axis of the pressure plate 31 is bent for the first time, and this part of the pressure plate 31 area is bent to be perpendicular to the original pressure plate 31 (i.e., the pressure plate body 312). The bent pressure plate 31 forms a flange 313, which extends from the pressure plate 31 towards the battery cell 220. At this time, the original area of ​​the flange 313 on the pressure plate 31 forms an air outlet 311.

[0166] Then, the elastic member 32 is installed on the pressure plate 31, so that the surface of the first connecting portion 321 of the elastic member 32 facing away from the cell 220 abuts against the bottom wall of the third mounting groove 315 of the pressure plate 31, and the inner edge of the first connecting portion 321 is connected to the outer peripheral surface of the partial flange 313. The outer peripheral surface of the flange 313 is the outer surface surrounding the central axis of the flange 313.

[0167] Subsequently, the portion of the flange 313 not connected to the first connecting part 321 is bent a second time, so that the first connecting part 321 is fixed by the flange 313 and the pressure plate body 312. The specific bending process is as follows: this portion of the flange 313 is bent at 45° away from the central axis of the pressure plate 31, and then riveted to make this portion of the flange 313 parallel to the pressure plate body 312. This portion of the flange 313 is the second sub-part 3132 of the flange 313. The flange 313 that only undergoes the first bending process is the first sub-part 3131 of the flange 313. The first sub-part 3131, the second sub-part 3132, and the bottom wall of the third mounting groove 315 together form the first slot 314.

[0168] Please refer to the following: Figure 5a , Figure 5b , Figure 13a and Figure 13b , Figure 13a yes Figure 9 The diagram shows a structural schematic of the first seal 33 of the pressure relief valve assembly 30 at an angle. Figure 13b yes Figure 9 A schematic diagram of the first seal 33 of the pressure relief valve assembly 30 from another angle.

[0169] The first seal 33 is located in the second groove 113 of the first mounting groove 11 of the top cover 10. There is a gap between the outer peripheral surface of the first seal 33 and the inner peripheral wall of the second groove 113 to allow gas in the power supply core 220 to pass through. The outer peripheral surface of the first seal 33 is the outer surface surrounding the central axis of the first seal 33.

[0170] The first sealing element 33 may include a first sealing body 331 and a retaining wall 332. The retaining wall 332 is connected around the outer edge of the first sealing body 331 and protrudes from the first sealing element 33 toward the elastic element 32 relative to the first sealing body 331. That is, the retaining wall 332 is annular and surrounds the first sealing body 331. The retaining wall 332 and the first sealing body 331 can be an integral structure formed by means such as integral molding.

[0171] The first sealing body 331 may include a first surface 3311 and a second surface 3312. The first surface 3311 and the second surface 3312 are disposed opposite each other in the thickness direction (Z direction in the figure) of the first sealing body 331. The first surface 3311 faces away from the battery cell 220. The first surface 3311 can abut against the elastic member 32. The second surface 3312 faces the battery cell 220. The second surface 3312 can abut against the second sealing member 34.

[0172] The portion of the first surface 3311 that contacts the elastic member 32 can be planar. Specifically, the first surface 3311 may include an abutting surface 3311a that abuts against the elastic member 32. That is, the abutting surface 3311a forms at least a portion of the first surface 3311 and extends along the circumferential direction of the first sealing body 331. The circumferential direction of the first sealing body 331 is the direction surrounding the central axis of the first sealing body 331. The abutting surface 3311a is arranged parallel to the bottom wall of the first mounting groove 11 of the top cover 10.

[0173] It is understandable that by aligning the abutment surface 3311a of the first seal 33 parallel to the bottom wall of the first mounting groove 11 of the top cover 10, the contact position between the elastic element 32 and the first seal 33 can be kept flat, thus ensuring the structural stability of the pressure relief valve assembly 30 during pressure relief. Furthermore, the smaller the area of ​​the abutment surface 3311a, the better its flatness is guaranteed.

[0174] In one possible application scenario, the distance between the first surface 3311 and the opening of the first mounting groove 11 of the top cover 10 remains constant from the central axis of the first sealing body 331 toward the retaining wall 332, then gradually increases and then remains constant again. That is, the central region of the first surface 3311 near the central axis of the first sealing body 331 protrudes relative to the edge region of the first surface 3311 away from the central axis of the first sealing body 331 (i.e., the region where the abutment surface 3311a is located).

[0175] In other application scenarios, the central region of the first surface 3311 near the central axis of the first sealing body 331 can also be recessed relative to the edge region of the first surface 3311 away from the central axis of the first sealing body 331 (i.e., the region where the contact surface 3311a is located), so that the contact position between the elastic member 32 and the first sealing member 33 can remain flat.

[0176] In the embodiments of this application, the second surface 3312 may be arranged parallel to the first surface 3311, and the distance between them remains unchanged. That is, the second surface 3312 has a structure corresponding to the first surface 3311. In some other embodiments, the structural relationship between the second surface 3312 and the first surface 3311 may not be limited.

[0177] The retaining wall 332 is connected to the first sealing body 331 and protrudes from the first surface 3311 of the first sealing body 331. The retaining wall 332 may be perpendicular to the first sealing body 331. In some other embodiments, the retaining wall 332 may also be inclined to the first sealing body 331. The retaining wall 332 may surround part of the elastic member 32 and together with the first sealing body 331, form a receiving space for accommodating the elastic member 32.

[0178] It is understandable that by setting a retaining wall 332 in the first sealing member 33, the retaining wall 332 can serve as a stop position in the first sealing member 33, thereby limiting the movement distance of the elastic member 32 relative to the first sealing member 33, preventing the elastic member 32 from slipping off the first sealing member 33, and thus having a good limiting effect.

[0179] The baffle 332 is spaced apart from the sidewall of the first mounting groove 11 of the top cover 10. That is, the baffle 332 is spaced apart from the second stepped surface 115 of the top cover 10. The gap area between the outer peripheral surface of the baffle 332 and the second stepped surface 115 of the top cover 10 forms the first air passage S1. The outer peripheral surface of the baffle 332 is the outer surface surrounding the central axis of the baffle 332. The first air passage S1 is connected to the first sub-air passage S31 of the elastic member 32 for the passage of gas within the power supply core 220.

[0180] The end of the retaining wall 332 away from the first sealing body 331 is spaced apart from the pressure plate 31. In the thickness direction of the top cover assembly 100, the distance between the end of the retaining wall 332 away from the first sealing body 331 and the surface of the pressure plate 31 facing the elastic member 32 is a first distance d1. The magnitude of the first distance d1 can be used to limit the degree to which the elastic member 32 is compressed.

[0181] It is understandable that when the first seal 33 is pushed upward by the air pressure inside the battery cell 220 and compresses the elastic member 32, the end of the baffle 332 away from the first sealing body 331 will approach the surface of the pressure plate 31 facing the elastic member 32, and the first distance d1 will decrease. Therefore, if the first distance d1 is set too large, the baffle 332 can float a greater distance, the first sealing body 331 can float a greater distance, and the elastic member 32 will be compressed to a greater degree. However, if the elastic member 32 is compressed too much, it will undergo plastic deformation and be difficult to return to its original state. Therefore, in the embodiments of this application, the first distance d1 is set in the range of 0.1mm to 0.5mm (including the endpoint values ​​of 0.1mm and 0.5mm). The first distance d1 within this range can ensure the normal venting function of the pressure relief valve assembly 30, and can also avoid the situation where the elastic member 32 is compressed too much and undergoes plastic deformation that is difficult to return to its original state due to the first distance d1 being too large, thus ensuring good reliability.

[0182] The gap between the first sealing member 33 and the pressure plate 31 forms a second air passage S2. The second air passage S2 includes the gap between the end of the baffle 332 away from the first sealing body 331 and the pressure plate 31, as well as the receiving space formed by the baffle 26 and the first sealing body 331. The second air passage S2 is connected to the first sub-air passage S31 of the elastic member 32 and is used to allow gas to pass through the power supply core 220.

[0183] Please refer to the following: Figure 5a , Figure 5b , Figure 14a and Figure 14b , Figure 14a yes Figure 9 A schematic diagram of the structure of the second seal 34 of the pressure relief valve assembly 30 at an angle. Figure 14b yes Figure 9 A schematic diagram of the second seal 34 of the pressure relief valve assembly 30 from another angle.

[0184] The second seal 34 is located between the first seal 33 and the bottom wall of the first mounting groove 11 of the top cover 10. Specifically, the second seal 34 is located within the second groove 113 of the first mounting groove 11 of the top cover 10 and abuts against the bottom wall of the second groove 113. That is, the second seal 34 abuts against the bottom wall of the first mounting groove 11 of the top cover 10. The side of the second seal 34 facing away from the bottom wall of the first mounting groove 11 of the top cover 10 abuts against the second surface 3312 of the first seal 33. There is a gap between the second seal 34 and the inner peripheral wall of the second groove 113. That is, there is a gap between the second seal 34 and the inner peripheral wall (i.e., the second stepped surface 115) of the first mounting groove 11. The distance between the outer peripheral surface of the second seal 34 and the second stepped surface 115 of the top cover 10 can be in the range of 0 to 0.17 mm (including the endpoint value of 0.17 mm, but excluding the endpoint value of 0 mm). The outer peripheral surface of the second seal 34 is the outer surface surrounding the central axis of the second seal 34.

[0185] Understandably, by setting the distance between the outer peripheral surface of the second seal 34 and the second stepped surface 115 of the top cover 10 within the aforementioned range, the second seal 34 can be more easily installed in the first mounting groove 11 of the top cover 10. This avoids the second seal 34 from being poorly assembled due to excessively small gaps, resulting in twisting and deformation, which could lead to sealing failure of the pressure relief valve assembly 30. At the same time, it also avoids air leakage due to excessively large gaps.

[0186] The second seal 34 is also located on the outer edge of the first pressure relief hole 12 of the top cover 10. Specifically, the second seal 34 is arranged around the first pressure relief hole 12 of the top cover 10 in the circumferential direction. The circumferential direction of the first pressure relief hole 12 is the direction around the central axis of the first pressure relief hole 12. That is, the second seal 34 is annular and surrounds the first pressure relief hole 12.

[0187] The second seal 34 can be made of a sealing material with low-temperature resistance. For example, the second seal 34 can be made of ethylene propylene diene monomer (EPDM) rubber.

[0188] The second seal 34 may include an inner ring 341 and an outer ring 342. The inner ring 341 abuts against the bottom wall of the first seal 33 and the first mounting groove 11 of the top cover 10. The inner ring 341 is in line contact with the first seal 33. And / or, the inner ring 341 is in line contact with the first mounting groove 11. The outer ring 342 is connected around the outer edge of the inner ring 341. In the thickness direction (Z direction in the figure), the thickness of the outer ring 342 is less than the thickness of the inner ring 341. The outer ring 342 is also located between the first seal 33 and the bottom wall of the first mounting groove 11 of the top cover 10, and is spaced apart from both the first seal 33 and the bottom wall of the first mounting groove 11 of the top cover 10.

[0189] It is understandable that by making the thickness of the outer ring 342 less than the thickness of the inner ring 341, there can be gaps between the outer ring 342 and the first seal 33, as well as between the outer ring 342 and the bottom wall of the first mounting groove 11 of the top cover 10. These gaps can serve as channels for the gas inside the cell 220 to be discharged to the outside of the battery 200, making the gas flow smoother.

[0190] Specifically, the thickness of the second seal 34 increases first, then decreases, and finally remains constant from near the central axis of the second seal 34 towards the direction away from the central axis of the second seal 34. Therefore, there is a maximum thickness in the inner ring body 341, namely the first thickness T1. At the maximum thickness of the inner ring body 341, the second seal 34 contacts the first seal 33 and / or the bottom wall of the first mounting groove 11 of the top cover 10. That is, there is a line contact between the second seal 34 and the first seal 33, and / or a line contact between the second seal 34 and the bottom wall of the first mounting groove 11 of the top cover 10. Therefore, there are gaps between the second seal 34 and the first seal 33 and the bottom wall of the first mounting groove 11 of the top cover 10 in other parts of the inner ring body 341 and in the outer ring body 342. These gaps can serve as channels for gas in the cell 220 to escape to the outside of the battery 200.

[0191] In some other embodiments, the thickness of the second seal 34 decreases first and then remains constant from the direction near the central axis of the second seal 34 toward the direction away from the central axis of the second seal 34. This can also make the second seal 34 in line contact with the first seal 33, and / or, the second seal 34 in line contact with the bottom wall of the first mounting groove 11.

[0192] It is understandable that if the second seal 34 forms surface contact with the top cover 10 and / or the first seal 33, insufficient flatness of the second seal 34 may cause local depressions, thereby affecting the sealing effect of the pressure relief valve assembly 30 after assembly. Therefore, by making the second seal 34 form line contact with the top cover 10 and / or the first seal 33, the sealing effect of the pressure relief valve assembly 30 can be improved.

[0193] In one possible application scenario, the inner ring 341 of the second seal 34 has a circular cross-sectional shape along the radial direction of the second seal 34, and the maximum thickness of the second seal 34 is equal to the diameter of this circle. The outer ring 342 of the second seal 34 has a rectangular cross-sectional shape along the radial direction of the second seal 34. This can prevent the second seal 34 from moving in its radial direction and improve the structural stability of the second seal 34 after assembly.

[0194] In the embodiments of this application, the portion of the second seal 34 with a constant thickness is the outer ring 342. The thickness of the outer ring 342 is a second thickness T2. The second thickness T2 is greater than or equal to 0.4 mm.

[0195] It is understandable that by setting the thickness of the outer ring 342 within the aforementioned range, it is possible to avoid the outer ring 342 being too thin and deformed, which would prevent the outer ring 342 from providing sufficient support when subjected to pressure. This would result in the relative position of the first seal 33 and the top cover 10 becoming unstable, and the outer ring 342 failing to play a positioning and guiding role.

[0196] In the embodiments of this application, the difference between the first thickness T1 and the second thickness T2 of the second seal 34 is greater than or equal to 30% of the first thickness T1. That is, (T1-T2) / T1≥30%.

[0197] It is understandable that by ensuring the thickness of the second seal 34 meets the aforementioned conditions, the thickness difference of the second seal 34 can be kept within a suitable range. This avoids the situation where the thickness difference of the second seal 34 is too small, causing the outer ring 342 to contact the top cover 10 and the first seal 33 when compressed, resulting in an unstable sealing interface and seal failure.

[0198] During battery use, chemical reactions occur inside the battery cell, producing a large amount of gas. If too much gas accumulates, the battery can easily explode. Therefore, an explosion-proof valve assembly is usually installed in the top cover. When the gas pressure inside the battery cell reaches a certain value, the gas will break through the explosion-proof valve assembly and be released to the outside of the battery, thus preventing an explosion due to excessive internal pressure. However, once the explosion-proof valve explodes, it cannot be reused, and the explosion of the explosion-proof valve will also greatly reduce the lifespan of the battery cell.

[0199] Therefore, in the embodiments of this application, by providing a pressure relief valve assembly 30 in the top cover assembly 100, the battery 200 can be repeatedly vented, and the impact on the battery cell 220 during the venting process can be reduced. Specifically, as Figure 5b As shown by the dashed arrow, when a certain amount of gas is generated inside the battery cell 220, causing the gas pressure at the first pressure relief hole 12 of the top cover 10 to be greater than or equal to the preset threshold of the pressure relief valve assembly 30, the gas will sequentially pass through the first pressure relief hole 12 of the top cover 10, the through hole on the second seal 34, and then push up the first seal 33, causing the first seal 33 to compress the elastic member 32. The second connecting portion 323 of the elastic member 32, under the pressure of the first seal 33, will move in the radial direction along the first connecting portion 321, thereby reducing the height of the elastic member 32. As the first seal 33 compresses the elastic member 32, the first seal 33 separates from the second seal 34. The gas will enter the first air passage S1 between the first seal 33 and the second step surface 115 of the top cover 10 through the gap between the second seal 34 and the first seal 33. Then, it enters the second air passage S2 between the baffle 332 of the second seal 34 and the pressure plate 31 through the first air passage S1, and then diffuses into the first sub-air passage S31 between the multiple legs 322 of the elastic member 32. Then, it passes through the second air passage S2 between the first sealing body 331 of the first seal 33 and the pressure plate 31, the second sub-air passage S32 of the first connecting part 321 of the elastic member 32, and the air outlet 311 of the pressure plate 31 in sequence, and is finally discharged to the outside of the battery 200.

[0200] Or, such as Figure 5b As shown by the solid arrow, with Figure 5b Unlike the path shown by the dashed arrow, when the gas passes through the second seal 34, it can also enter the gap between the second seal 34 and the second step surface 115 of the top cover 10 through the gap between the second seal 34 and the bottom wall of the first mounting groove 11, and then enter the first air passage S1 between the first seal 33 and the second step surface 115 of the top cover 10.

[0201] When the air pressure at the first pressure relief port 12 is less than the preset threshold of the pressure relief valve assembly 30, the rebound force of the elastic member 32 causes the first seal 33 to press against the second seal 34, keeping the pressure relief valve assembly 30 in a sealed state. The pressure relief valve assembly 30 will stop venting, and this cycle repeats to achieve one-way venting of the pressure relief valve assembly 30. For example, the preset threshold can be 0.2 MPa. Of course, in some other embodiments, the preset threshold can also be other values, and this is not strictly limited.

[0202] In summary, when the gas generated inside the battery cell 220 causes the gas pressure entering the first pressure relief hole 12 of the top cover 10 to be greater than or equal to the preset threshold of the pressure relief valve assembly 30, the pressure relief valve assembly 30 will begin to vent gas from the battery 200. When the gas pressure at the first pressure relief hole 12 of the top cover 10 is less than the preset threshold of the pressure relief valve assembly 30, the pressure relief valve assembly 30 will stop venting gas. That is, the pressure relief valve assembly 30 can repeatedly vent gas from the battery 200, greatly improving the service life of the battery cell 220.

[0203] Furthermore, due to the pressure difference between the inside and outside of the pressure relief valve assembly 30, the pressure relief valve can only be opened by the air pressure inside the battery cell 220, and cannot be opened from the outside of the battery 200. That is, the pressure relief valve assembly 30 is unidirectional. This prevents substances such as water molecules from entering the battery 200 through the pressure relief valve assembly 30 and causing battery 200 failure, further improving the reliability of the battery 200 and increasing its service life.

[0204] Furthermore, while the explosion-proof valve assembly F can function when a large amount of gas is generated inside the battery 200, resulting in high gas pressure, it cannot expel the gas when the amount of gas generated inside the cell 220 is insufficient to break through the threshold of the explosion-proof valve 60. Although this small amount of gas will not cause the battery 200 to explode, it can lead to bulging or deformation of the battery 200. The pressure relief valve assembly 30, by adjusting its opening threshold, can control the amount of gas discharged from the cell 220 into the battery 200, thus achieving the purpose of expelling the small amount of gas generated inside the battery 200.

[0205] Please refer to the following: Figure 7 and Figure 15 , Figure 15 yes Figure 3 A schematic diagram of the structure of the upper plastic 40 of the top cover assembly 100 shown.

[0206] The upper plastic 40 may include a fifth surface 41 and a sixth surface 42. The fifth surface 41 and the sixth surface 42 are disposed opposite to each other in the thickness direction (Z direction shown in the figure) of the upper plastic 40. The fifth surface 41 faces away from the battery cell 220. The sixth surface 42 faces the battery cell 220. The fifth surface 41 abuts against the surface of the second body 512 of the electrode post 50 near the electrode post base 52. The sixth surface 42 abuts against the surface of the fourth body 514 of the electrode post 50 facing away from the electrode post base 52.

[0207] The upper plastic 40 may be provided with a third through hole 43. The third through hole 43 can penetrate the fifth surface 41 and the sixth surface 42. That is, the third through hole 43 penetrates the upper plastic 40 along the thickness direction of the upper plastic 40. The third through hole 43 of the upper plastic 40 can be coaxially arranged and connected with the first through hole 16b of the top cover 10 and the second through hole 28b of the lower plastic 20. The third through hole 43 is used for the pole post 50 to pass through and for accommodating the third body 513 of the pole post 50. The inner surface of the third through hole 43 can abut against the outer peripheral surface of the third body 513 of the pole post 50. Wherein, the inner surface of the third through hole 43 is the inner surface surrounding the central axis of the third through hole 43. The outer peripheral surface of the third body 513 is the outer surface surrounding the central axis of the third body 513.

[0208] The number of upper plastic inserts 40 can be two. The two upper plastic inserts 40 are spaced apart along their length (X direction in the diagram). One upper plastic insert 40 is mounted on a positive terminal. The other upper plastic insert 40 is mounted on a negative terminal. The number of third through holes 43 can also be two, and the two third through holes 43 can be spaced apart along the length of the upper plastic inserts 40. One third through hole 43 is used for the positive terminal to pass through. The other third through hole 43 is used for the negative terminal to pass through.

[0209] The upper plastic 40 may be provided with a second slot 44. The opening of the second slot 44 is located on the outer peripheral surface of the upper plastic 40. The outer peripheral surface of the upper plastic 40 is the outer surface surrounding the central axis of the upper plastic 40. The second slot 44 may be formed by recessing from the outer peripheral surface of the upper plastic 40 into the interior of the upper plastic 40. The second slot 44 is arranged around the third through hole 43 in the circumferential direction. The circumferential direction of the third through hole 43 is the direction surrounding the central axis of the third through hole 43. The bottom wall of the second slot 44 is spaced apart from and parallel to the inner surface of the third through hole 43. That is, the second slot 44 is annular and surrounds the third through hole 43. The second slot 44 may include a first side surface 441 and a second side surface 442. The first side surface 441 and the second side surface 442 may be arranged opposite to each other in the thickness direction of the upper plastic 40. The first side surface 441 is close to the fifth surface 41. The second side surface 442 is close to the sixth surface 42. The second slot 44 may be used to install part of the top cover 10. The bottom wall of the second slot 44 abuts against the inner surface of the first through hole 16b of the top cover 10. The first side 441 abuts against the surface of the first protrusion 16c of the top cover 10 facing away from the top cover body 14. The second side 442 abuts against the bottom wall of the first groove 16a of the top cover 10.

[0210] For example, there may be two second slots 44, which are spaced apart along the length of the upper plastic 40. Each second slot 44 is connected to a portion of the top cover 10.

[0211] It is understood that by providing a second groove 44 recessed in the radial direction of the upper plastic 40 within the upper plastic 40 and connecting the second groove 44 to the top cover 10, the installation stability of the upper plastic 40 and the top cover 10 can be increased, preventing the top cover 10 from moving in the thickness direction of the top cover assembly 100.

[0212] Please refer to the following: Figure 7 and Figure 16 , Figure 16 yes Figure 3 This is a schematic diagram of the structure of the pole post 50 of the top cover assembly 100. The pole post 50 is mounted on the upper plastic 40, the top cover 10, and the lower plastic 20. The opposite ends of the pole post 50 protrude from the fifth surface 41 of the upper plastic 40 and the fourth surface 242 of the lower plastic 20, respectively. Specifically, the pole post 50 may include a pole post body 51 and a pole post base 52. The pole post base 52 is located on the side of the top cover 10 near the lower plastic 20. One end of the pole post body 51 is fixedly connected to the pole post base 52. The pole post body 51 passes through the second through hole 28b of the lower plastic 20, the first through hole 16b of the top cover 10, and the third through hole 43 of the upper plastic 40. The other end of the pole post body 51 extends out of the upper plastic 40.

[0213] The pole post body 51 may include a first body 511, a second body 512, a third body 513, and a fourth body 514. The first body 511, second body 512, third body 513, and fourth body 514 are sequentially connected and coaxially arranged. One end of the fourth body 514 is connected to the pole post base 52. The third body 513 is connected between the fourth body 514 and the second body 512. The first body 511 is connected to the surface of the second body 512 facing away from the third body 513. The pole post base 52 and the first body 511, second body 512, third body 513, and fourth body 514 of the pole post 50 can be an integral structure. The cross-sectional width of the first body 511 along the thickness direction (Z direction in the figure) of the pole post 50 is smaller than the cross-sectional width of the second body 512 along the thickness direction of the pole post 50. The cross-sectional width of the third main body 513 along the thickness direction of the pole post 50 is smaller than the cross-sectional width of the second main body 512 along the thickness direction of the pole post 50, and also smaller than the cross-sectional width of the fourth main body 514 along the thickness direction of the pole post 50. The cross-sectional width of the pole post base 52 along the thickness direction of the pole post 50 is larger than the cross-sectional width of the pole post main body 51 (including the first main body 511, the second main body 512, the third main body 513 and the fourth main body 514) along the thickness direction of the pole post 50.

[0214] Understandably, dividing the electrode post body 51 into four parts of different sizes allows for better installation of the upper plastic 40, top cover 10, and lower plastic 20 into their corresponding parts, preventing misalignment. Furthermore, the electrode post base 52 is larger than the electrode post body 51, effectively preventing the electrode post 50 from slipping off.

[0215] In the embodiments of this application, the first body 511 and the second body 512 of the pole post 50 protrude from the fifth surface 41 of the upper plastic 40. The surface of the second body 512 near the pole post base 52 abuts against the fifth surface 41 of the upper plastic 40. The third body 513 of the pole post 50 is located within the third through hole 43 of the upper plastic 40 and the first through hole 16b of the top cover 10, and is separated from the top cover 10 by the upper plastic 40. The outer peripheral surface of the third body 513 abuts against the inner surface of the third through hole 43 of the upper plastic 40. The fourth body 514 of the pole post 50 is located within the second through hole 28b of the lower plastic 20. There is a gap between the outer peripheral surface of the fourth body 514 and the inner surface of the second through hole 28b of the lower plastic 20. The surface of the fourth body 514 facing away from the pole post base 52 abuts against the sixth surface 42 of the upper plastic 40. Part of the electrode base 52 of the electrode 50 is located in the second through hole 28b of the lower plastic 20, and part of the electrode base 52 protrudes relative to the fourth surface 242 of the lower plastic 20.

[0216] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A cap assembly, characterized by, The top cover assembly comprises: a top cover comprising a first surface, the first surface being a surface of the top cover facing away from the lower plastic, the top cover being provided with a first pressure relief hole penetrating the top cover along a thickness direction of the top cover and a first mounting slot having an opening on the first surface, the first mounting slot being coaxially arranged with the first pressure relief hole and being in communication with the first pressure relief hole, the first mounting slot being configured to be connected with a pressure relief valve assembly, the first mounting slot comprising a first connecting surface forming at least part of a bottom wall of the first mounting slot, the first connecting surface being connected to an outer edge of the first pressure relief hole and surrounding the first pressure relief hole, a distance between the first connecting surface and the opening of the first mounting slot gradually decreasing from one end connected with the first pressure relief hole to an end away from the first pressure relief hole in the thickness direction of the top cover assembly; and a lower plastic connected with the top cover, the lower plastic being provided with a second pressure relief hole penetrating the lower plastic along a thickness direction of the lower plastic, the second pressure relief hole being in communication with the first pressure relief hole and being configured to allow electrolyte to pass through.

2. The roof assembly of claim 1, wherein, The lower plastic is further provided with a second mounting slot having an opening on a surface of the lower plastic close to the top cover, the second pressure relief hole being located on an outer edge of a bottom wall of the second mounting slot and being in communication with the second mounting slot; part of the top cover is located in the second mounting slot, a gap region between the top cover and the bottom wall of the second mounting slot and a gap region between the top cover and a peripheral side wall of the second mounting slot cooperatively forming a flow channel for electrolyte to pass through, the flow channel being connected between the first pressure relief hole and the second pressure relief hole and being in communication with the first pressure relief hole and the second pressure relief hole.

3. The roof assembly of claim 2, wherein, The second mounting slot comprises a second connecting surface forming at least part of the bottom wall of the second mounting slot, the second connecting surface being located between the first pressure relief hole and the second pressure relief hole, a distance between the second connecting surface and the opening of the second mounting slot gradually decreasing from one end towards the second pressure relief hole to an end away from the second pressure relief hole in the thickness direction of the top cover assembly.

4. The roof assembly of claim 2, wherein, The second mounting slot is coaxially arranged with the first mounting slot, the lower plastic comprising a first edge and a second edge, the first edge and the second edge being oppositely arranged in a width direction of the lower plastic, a distance between a central axis of the second mounting slot and the first edge being equal to a distance between the central axis of the second mounting slot and the second edge.

5. The roof assembly of claim 2, wherein, The lower plastic comprises a lower plastic body and a baffle, at least part of the second pressure relief hole being arranged in the lower plastic body, one end of the baffle being connected to a surface of the lower plastic body facing away from the top cover, the other end of the baffle extending away from the lower plastic body, the baffle being located on a side of the second pressure relief hole away from the second mounting slot.

6. The roof assembly of claim 5, wherein, The lower plastic further comprises a first protrusion fixedly connected to the lower plastic body and protruding away from the surface of the top cover relative to the lower plastic body, and the second pressure relief hole and the second mounting groove are both arranged on the lower plastic body and the first protrusion. The first protrusion protrudes away from the surface of the top cover relative to the lower plastic body by a first height, and the baffle protrudes away from the surface of the top cover relative to the lower plastic body by a second height, the second height being greater than the first height.

7. The roof assembly of claim 6, wherein, The lower plastic further comprises a support portion connected to the surface of the lower plastic body away from the top cover and arranged in a spaced manner with the baffle, the support portion being used to abut against the battery cell, the baffle protruding away from the surface of the top cover relative to the lower plastic body by a second height, and the support portion protruding away from the surface of the top cover relative to the lower plastic body by a third height, the third height being greater than the second height.

8. The roof assembly of any of claims 1-7, wherein, The top cover assembly further comprises a pressure relief valve assembly located in the first mounting groove, the pressure relief valve assembly comprising a pressing plate, an elastic member, a first sealing member and a second sealing member arranged in sequence, the pressing plate being close to the opening of the first mounting groove, the elastic member being elastically connected between the pressing plate and the first sealing member, and the second sealing member being sealingly connected between the first sealing member and the bottom wall of the first mounting groove.

9. The roof assembly of claim 8, wherein, The second sealing member and the first sealing member are in linear contact, and / or the second sealing member and the bottom wall of the first mounting groove are in linear contact.

10. The roof assembly of claim 8, wherein, The elastic member comprises a first connecting portion and a plurality of legs, the first connecting portion abutting against the pressing plate, the inner edge of the first connecting portion being covered by the pressing plate, and the plurality of legs being arranged in a spaced manner in the circumferential direction of the first connecting portion, one end of each leg being fixedly connected to the outer edge of the first connecting portion, and the other end of each leg abutting against the first sealing member, the leg being capable of moving in the radial direction of the first connecting portion relative to the first sealing member.

11. The roof assembly of claim 10, wherein, The elastic member further comprises a second connecting portion, one end of each leg being fixedly connected to the outer edge of the first connecting portion, and the other end of each leg being fixedly connected to the inner edge of the second connecting portion, the second connecting portion being arranged in a spaced manner with the first connecting portion in the thickness direction of the elastic member and abutting against the first sealing member, the second connecting portion being capable of moving in the radial direction of the first connecting portion relative to the first sealing member.

12. The roof assembly of claim 8, wherein, The pressing plate comprises a pressing plate body and a flange, one end of the flange being connected to the pressing plate body, the other end of the flange being projected in the thickness direction of the pressing plate and falling into the pressing plate body, the flange being bent relative to the pressing plate body, the flange and the pressing plate body cooperating to form a first clamping groove, and part of the elastic member being located in the first clamping groove and abutting between the pressing plate body and the flange.

13. The roof assembly of claim 8, wherein, The first mounting groove comprises a first groove and a second groove, the first groove and the second groove are coaxially arranged, a cross-sectional width of the first groove along a thickness direction of the top cover is greater than a cross-sectional width of the second groove along the thickness direction of the top cover, a first step surface is formed at a connection between the first groove and the second groove, the pressing plate is located in the first groove and abuts against the first step surface, the elastic member is located in the first groove and the second groove, and the first sealing member and the second sealing member are both located in the second groove.

14. A battery, characterized by The battery comprises a battery cell, a shell, and the top cover assembly according to any one of claims 1-13, the top cover assembly is connected to the shell and forms an accommodation space together with the shell, and the battery cell is located in the accommodation space.

15. An electrical device, characterized by The electric device comprises the battery according to claim 14.

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