Top cover, top cover assembly, battery and energy storage device

Abstract

The application provides a top cover, a top cover assembly, a battery and an energy storage device. The top cover comprises a main body, an explosion-proof hole, a liquid injection hole and a first reinforcing structure. The main body comprises a top cover body and a first connecting part, and the first connecting part is protruded on the top cover body. The explosion-proof hole is arranged on the first connecting part and penetrates the first connecting part along the thickness direction of the first connecting part, and is used for being connected with an explosion-proof valve. The liquid injection hole is arranged on the first connecting part and penetrates the first connecting part along the thickness direction of the first connecting part, and is arranged at intervals with the explosion-proof hole. The first reinforcing structure is recessed on the first connecting part, and the recessed direction of the first reinforcing structure relative to the first connecting part is opposite to the protruded direction of the first connecting part relative to the top cover body. The first reinforcing structure is located between the explosion-proof hole and the liquid injection hole and is arranged at intervals with the explosion-proof hole and the liquid injection hole. The technical scheme of the application can avoid the abnormal opening of the explosion-proof valve when the large-capacity battery is in thermal runaway, and improve the safety performance of the battery.

Description

Technical Field

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

[0002] With the development of green energy, batteries with recyclable characteristics are becoming increasingly popular. High-capacity batteries are gaining market favor due to their ability to provide longer energy reserves. However, in the event of thermal runaway, the explosion-proof valve of a high-capacity battery may malfunction, leading to abnormal opening and ultimately causing safety hazards. Summary of the Invention

[0003] The embodiments of this application provide a top cover, a top cover assembly, a battery, and an energy storage device, which can prevent the explosion-proof valve from opening abnormally when a large-capacity battery experiences thermal runaway, thereby improving the safety performance of the battery.

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

[0005] The main body includes a top cover body and a first connecting part, the first connecting part protruding from the top cover body;

[0006] An explosion-proof hole is provided in the first connecting part and penetrates the first connecting part along the thickness direction of the first connecting part. The explosion-proof hole is used to connect with an explosion-proof valve.

[0007] The injection hole is located at the first connecting portion and extends through the first connecting portion along its thickness direction; the injection hole and the explosion-proof hole are spaced apart.

[0008] A reinforcing structure is recessed in the first connecting portion. The direction of the recess of the reinforcing structure relative to the first connecting portion is opposite to the direction of the protrusion of the first connecting portion relative to the top cover body. The reinforcing structure is located between the explosion-proof hole and the liquid injection hole, and is spaced apart from both the explosion-proof hole and the liquid injection hole.

[0009] Understandably, in related technologies, a vacuum is required to create a negative pressure inside the battery during electrolyte injection, allowing the electrolyte to enter through the injection tube under this negative pressure. However, the negative pressure generated during battery injection can easily deform the top cover. If this deformation extends to the explosion-proof valve, it can pull on the valve, causing further deformation and reducing its reliability. This could lead to unstable valve opening or short-side opening, ultimately posing a safety hazard to the battery.

[0010] Therefore, in the embodiments of this application, by providing a reinforcing structure on the top cover, the local strength of the top cover can be increased, the pressure applied to the top cover can be dispersed, the free deformation space of the top cover under force can be limited, and the possibility of deformation of the top cover can be reduced. Furthermore, since the reinforcing structure is also provided between the injection hole and the explosion-proof hole, the strength of the area between the injection hole and the explosion-proof hole of the top cover can be improved. When injection causes deformation of the top cover, the deformation zone extending from the injection hole to the reinforcing structure is blocked, preventing the explosion-proof valve from being pulled, thus ensuring that the explosion-proof valve will not deform, enhancing the reliability of the explosion-proof valve, and avoiding abnormal valve opening in the event of thermal runaway in a large-capacity battery, thereby improving the safety performance of the battery.

[0011] In one possible implementation, the first connecting portion protrudes away from the battery cell relative to the top cover body, and the reinforcing structure is recessed towards the battery cell relative to the first connecting portion; or,

[0012] The first connecting portion protrudes towards the battery cell relative to the top cover body, and the reinforcing structure is recessed away from the battery cell relative to the first connecting portion.

[0013] In one possible implementation, the top cover further includes a second reinforcing structure, which is recessed in the first connecting portion and located on the side of the explosion-proof hole away from the injection hole. The second reinforcing structure is spaced apart from the explosion-proof hole, and the recessed direction of the second reinforcing structure relative to the first connecting portion is opposite to the protruding direction of the first connecting portion relative to the top cover body.

[0014] In one possible implementation, the first connecting portion protrudes away from the battery cell relative to the top cover body, and the second reinforcing structure concave towards the battery cell relative to the first connecting portion; or,

[0015] The first connecting portion protrudes towards the battery cell relative to the top cover body, and the second reinforcing structure is recessed away from the battery cell relative to the first connecting portion.

[0016] In one possible implementation, the first connecting portion includes a first surface and a second surface, the first surface and the second surface being disposed opposite to each other in the thickness direction of the top cover, and the second surface being oriented toward the battery cell;

[0017] The first reinforcing structure is recessed relative to the first surface and protrudes relative to the second surface; and / or,

[0018] The second reinforcing structure is recessed relative to the first surface and protrudes relative to the second surface.

[0019] In one possible implementation, the top cover body includes a third surface and a fourth surface, the third surface and the fourth surface being disposed opposite to each other in the thickness direction of the top cover, the fourth surface being oriented toward the battery cell;

[0020] The surface of the first reinforcing structure facing away from the first connecting portion is flush with the fourth surface; and / or,

[0021] The surface of the second reinforcing structure that faces away from the first connecting portion is flush with the fourth surface.

[0022] In one possible implementation, the first reinforcing structure includes a first transition portion and a first platform portion. The first platform portion is disposed parallel to the top cover body. The first transition portion is disposed around the outer edge of the first platform portion and connects the outer edge of the first platform portion and the inner edge of the first connecting portion. The thickness of the first platform portion is equal to the thickness of the top cover body; and / or,

[0023] The first connecting portion includes a first sub-part and a second sub-part. The first sub-part is arranged parallel to the top cover body, and the second sub-part is arranged around the outer edge of the first sub-part and connected between the outer edge of the first sub-part and the top cover body. The thickness of the first sub-part is equal to the thickness of the top cover body.

[0024] In one possible implementation, the second reinforcing structure includes a second transition portion and a second platform portion. The second platform portion is disposed parallel to the top cover body. The second transition portion is disposed around the outer edge of the second platform portion and connected to the outer edge of the second platform portion and the inner edge of the first connecting portion. The thickness of the second platform portion is equal to the thickness of the top cover body.

[0025] In one possible implementation, the ratio of the distance between the first reinforcing structure and the injection hole to the distance between the first reinforcing structure and the explosion-proof hole is in the range of 3:1 to 7:1.

[0026] In one possible implementation, the ratio of the length to the width of the body is greater than 4.

[0027] In one possible implementation, the ratio of the maximum dimension of the first reinforcing structure along the width direction of the body to the maximum dimension of the first reinforcing structure along the length direction of the body is in the range of 1:1 to 3:1; and / or,

[0028] The ratio of the maximum dimension of the second reinforcing structure along the width direction of the main body to the maximum dimension of the second reinforcing structure along the length direction of the main body is in the range of 1:1 to 3:1.

[0029] In one possible implementation, the ratio of the length to the width of the first reinforcing structure is within the range of 1:1 to 3:1, wherein the length of the first reinforcing structure is its dimension along the width direction of the main body, and the width of the first reinforcing structure is its dimension along the length direction of the main body; and / or,

[0030] The ratio of the length to the width of the second reinforcing structure is in the range of 1:1 to 3:1, wherein the length of the second reinforcing structure is the dimension of the second reinforcing structure along the width direction of the main body, and the width of the second reinforcing structure is the dimension of the second reinforcing structure along the length direction of the main body.

[0031] In one possible implementation, the length of the first reinforcing structure is in the range of 20mm-40mm, wherein the length of the first reinforcing structure is the dimension of the first reinforcing structure along the width direction of the main body, or the length of the first reinforcing structure is the dimension of the first reinforcing structure along the length direction of the main body; and / or,

[0032] The length of the second reinforcing structure is in the range of 20mm-40mm, wherein the length of the second reinforcing structure is the dimension of the second reinforcing structure along the width direction of the main body, or the length of the second reinforcing structure is the dimension of the second reinforcing structure along the length direction of the main body.

[0033] In one possible implementation, the maximum dimension of the first reinforcing structure along the width direction of the body accounts for a proportion of the width of the body in the range of 30%-60%; and / or,

[0034] The maximum dimension of the second reinforcing structure along the width direction of the main body is in the range of 30%-60% of the width of the main body.

[0035] In one possible implementation, the distance between the first reinforcing structure and the explosion-proof hole along the length of the top cover is in the range of 10mm-30mm; and / or,

[0036] Along the length of the top cover, the distance between the second reinforcing structure and the explosion-proof hole is in the range of 10mm-30mm.

[0037] In one possible implementation, any one or more of the first reinforcing structure, the second reinforcing structure, and the first connecting portion are formed by stamping.

[0038] Secondly, this application provides a top cover assembly, the top cover assembly including an explosion-proof valve and a top cover as described above, the explosion-proof valve being connected to the explosion-proof hole.

[0039] In one possible implementation, the top cover assembly further includes a top patch attached to the top cover and covering the first reinforcing structure.

[0040] In one possible implementation, the top patch includes a top patch body and a second connecting portion, the second connecting portion protruding from the top patch body, and the protrusion direction of the second connecting portion relative to the top patch body is the same as the protrusion direction of the first connecting portion relative to the top cover body.

[0041] At least a portion of the first connecting portion is located within the second connecting portion, or at least a portion of the second connecting portion is located within the first connecting portion.

[0042] Thirdly, this application provides a battery comprising a cell, a housing, and a top cover assembly as described in any one of claims 16-18, wherein the top cover assembly is connected to the housing and forms a receiving space with the housing, and the cell is located within the receiving space.

[0043] Fourthly, this application provides an energy storage device, which includes the battery described above. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the energy storage system provided in an embodiment of this application;

[0045] Figure 2 This is a schematic diagram of a battery structure provided in an embodiment of this application;

[0046] Figure 3 This is a schematic diagram of a top cover assembly provided in an embodiment of this application;

[0047] Figure 4 yes Figure 3 The exploded view of the top cover assembly is shown.

[0048] Figure 5a yes Figure 3 A schematic diagram of an angle of one structure of the top cover assembly shown;

[0049] Figure 5b yes Figure 5a A structural schematic diagram of the top cover from another angle is shown;

[0050] Figure 5c yes Figure 5a A structural schematic diagram of the top cover at another angle;

[0051] Figure 6 It is along Figure 5c A schematic cross-sectional view of the top cover obtained by cutting along section line AA as shown;

[0052] Figure 7 It is along Figure 5c Another cross-sectional view of the top cover structure obtained by cutting along section line BB;

[0053] Figure 8a yes Figure 3 Another structural schematic diagram of the top cover of the top cover assembly shown;

[0054] Figure 8b yes Figure 3 Another structural schematic diagram of the top cover of the top cover assembly shown;

[0055] Figure 9a yes Figure 3 A schematic diagram of the top patch of the top cover assembly at one angle;

[0056] Figure 9b yes Figure 9a A schematic cross-sectional view of the top patch obtained by cutting along the cutting line CC shown.

[0057] Figure 10 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 the cutting line DD shown.

[0058] Figure 11 yes Figure 3 A schematic diagram of the structure of the upper plastic part of the top cover assembly at one angle;

[0059] Figure 12 yes Figure 3 A schematic diagram of the sealing ring at one angle of the top cover assembly shown;

[0060] Figure 13 yes Figure 3 A schematic diagram of the structure of the lower plastic of the top cover assembly at one angle;

[0061] Figure 14 yes Figure 3 A schematic diagram of the structure of the connecting piece of the top cover assembly at one angle is shown;

[0062] Figure 15 It is along Figure 3 Another cross-sectional view of a portion of the top cover assembly obtained by cutting along section line DD;

[0063] Figure 16 yes Figure 3 A schematic diagram of one structure of the pole of the top cover assembly shown;

[0064] Figure 17 yes Figure 3 Another structural schematic diagram of the pole of the top cover assembly shown;

[0065] Figure 18a yes Figure 3 A schematic diagram of the structure of the filler of the top cover assembly at one angle;

[0066] Figure 18b yes Figure 3 A schematic diagram of the structure of the filler of the top cover assembly at one angle.

[0067] Figure label:

[0068] Energy storage system 500, power conversion device 510, first user load 520, second user load 530, energy storage device 400, battery 300, battery cell 310, housing 320, top cover assembly 200, top cover 100, top patch 210, upper plastic 220, sealing ring 230, lower plastic 240, connecting piece 250, terminal post 260, explosion-proof valve 270, explosion-proof valve protection plate 280, main body 70, top cover body 10, first connecting part 20, explosion-proof hole 30, liquid injection hole 40, first filling Reinforcing structure 50a, first surface 21, second surface 22, third surface 11, fourth surface 12, first through hole 13, first sub-part 23, second sub-part 24, first hole 31, second hole 32, third hole 33, retaining wall 60, fourth hole 61, first transition part 51a, first platform part 52a, fifth surface 521, sixth surface 522, second reinforcing structure 50b, second transition part 51b, second platform part 52b, seventh surface 523, eighth surface 524, top patch body 214. Second connecting part 215, second through hole 211, fifth hole 212, marking hole 213, upper plastic body 221, upper plastic protrusion 222, first mounting groove 2211, third through hole 223, fourth through hole 231, fifth through hole 241, first part 242, second part 243, first connecting section 251, second connecting section 252, sixth through hole 2511, pole base 261, pole body 262, first body 262a, second body 262b, filler 290, first filler part 291. Second filling part; 292. Third filling part; 293. Second mounting groove; 294. Sixth hole; 2911. Distance D1 between the first reinforcing structure 50a and the injection hole 40; Distance D2 between the first reinforcing structure 50a and the explosion-proof hole 30; Distance D4 between the second reinforcing structure 50b and the explosion-proof hole 30; Maximum dimension D5 of the first reinforcing structure 50a along the width direction of the main body 70; Width D6 of the main body 70; Maximum dimension D7 of the second reinforcing structure 50b along the width direction of the main body 70. Detailed Implementation

[0069] For ease of understanding, the terminology used in the embodiments of this application will be explained first.

[0070] 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.

[0071] 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.

[0072] 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.

[0073] 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.

[0074] Taking electrochemical energy storage as an example, the embodiments of this application provide an energy storage device 400. The energy storage device 400 is equipped with a set of chemical batteries. It mainly uses 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 electrical energy is released for use, or transferred to places with a shortage of electricity for use.

[0075] 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 energy storage devices (400 types) include:

[0076] 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.

[0077] Small and medium-sized energy storage cabinets used in commercial and industrial energy storage scenarios on the user side, and small residential 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 with energy storage devices typically charge the cabinets / boxes during off-peak periods to reduce costs; during peak periods, they release the electricity from the energy storage devices 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 residential energy storage devices effectively provides users with backup power for themselves and the power grid, eliminating the inconvenience caused by frequent power outages due to disasters or other reasons.

[0078] Please see Figure 1 , Figure 1 This is a schematic diagram of the energy storage system 500 provided in an embodiment of this application. This application uses a residential energy storage scenario as an example for illustration, but the energy storage device 400 of this application is not limited to residential energy storage scenarios.

[0079] This application provides an energy storage system 500, which includes a power conversion device 510 (e.g., a photovoltaic panel), a first user load 520 (e.g., a street light), a second user load 530 (e.g., a household appliance such as an air conditioner), and an energy storage device 400. The energy storage device 400 is a small energy storage box that can be wall-mounted to an outdoor wall. Specifically, the photovoltaic panel can convert solar energy into electrical energy during periods of low electricity prices, and the energy storage device 400 stores this electrical energy and supplies it to street lights and household appliances during peak electricity prices, or provides power during power outages / power interruptions.

[0080] The energy storage device 400 may include, but is not limited to, individual batteries, battery modules, battery packs, and battery systems. When the energy storage device 400 includes multiple batteries, the multiple batteries are electrically connected and all are located inside the casing of the energy storage device 400, 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 in 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 energy storage device 400 including batteries, but it should be understood that the energy storage device 400 is not limited thereto.

[0081] Please see Figure 2 , Figure 2 This is a schematic diagram of a battery 300 provided in an embodiment of this application.

[0082] For ease of description, the length direction of battery 300 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.

[0083] The battery 300 may include a cell 310, a housing 320, and a top cover assembly 200. The top cover assembly 200 is connected to the housing 320 and encloses the housing 320 to form a receiving space, within which the cell 310 is located. Exemplarily, the top cover assembly 200 may be welded to the housing 320. The housing 320 may be made of a metallic material, such as aluminum alloy. The battery 300 may be a cylindrical battery or a prismatic battery, etc.

[0084] It should be noted that, Figure 2 The purpose is merely to illustratively describe the connection relationship between the battery cell 310, the housing 320, and the top cover assembly 200, and is not to specifically limit the connection positions, specific structures, or quantities of each device. In other embodiments of this application, the battery 300 may include a... 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.

[0085] Please see Figure 3 and Figure 4 , Figure 3 This is a schematic diagram of a top cover assembly 200 provided in an embodiment of this application. Figure 4 yes Figure 3 The exploded structural diagram of the top cover assembly 200 shown.

[0086] The top cover assembly 200 may include a top cover 100, a top patch 210, an upper plastic piece 220, a sealing ring 230, a lower plastic piece 240, a connecting piece 250, a terminal post 260, an explosion-proof valve 270, and an explosion-proof valve protection piece 280. The top patch 210 and the lower plastic piece 240 are respectively connected to two opposite surfaces of the top cover 100 in the thickness direction (Z direction in the diagram). The upper plastic piece 220 is mounted on the top cover 100, with a portion of it passing through the top patch 210 and protruding from the outside of the top cover assembly 200. The terminal post 260 is mounted on the upper plastic piece 220, the top patch 210, the top cover 100, and the lower plastic piece 240, and can serve as an electrode lead-out of the battery 300. The explosion-proof valve 270 is connected to the top cover 100 and is spaced apart from the terminal post 260 on the top cover 100 to provide pressure relief protection for the battery 300. An explosion-proof valve protection plate 280 is connected to the top cover 100 and covers the explosion-proof valve 270. A connecting piece 250 is installed on the side of the lower plastic 240 away from the top cover 100 and is sleeved on the terminal post 260. The end of the connecting piece 250 away from the terminal post 260 is used for electrical connection with the battery cell 310, so that the connecting piece 250 is electrically connected between the terminal post 260 and the battery cell 310, realizing the electrical connection between the terminal post 260 and the battery cell 310. A sealing ring 230 is disposed around the outside of the terminal post 260 and is located on the same side of the top cover 100 as the lower plastic 240. The sealing ring 230 also abuts between the top cover 100 and the connecting piece 250.

[0087] The device includes two terminals 260, one for positive and one for negative. The two terminals 260 are spaced apart along the length of the top cover 100 (X direction in the diagram). There are also two upper plastic inserts 220. One upper plastic insert 220 is fitted onto the positive terminal, and the other upper plastic insert 220 is fitted onto the negative terminal. There are also two sealing rings 230. One sealing ring 230 is fitted onto the positive terminal, and the other sealing ring 230 is fitted onto the negative terminal. There are also two connecting tabs 250. One connecting tab 250 is fitted onto the positive terminal, and the other connecting tab 250 is fitted onto the negative terminal.

[0088] The following description uses the assembly of a terminal post 260, an upper plastic piece 220, a sealing ring 230, a connecting piece 250, and a top cover 100, a top patch 210, and a lower plastic piece 240 as an example to illustrate the structure of the top cover assembly 200. Unless otherwise specified, the description of a terminal post 260, an upper plastic piece 220, a sealing ring 230, and a connecting piece 250 can be applied to other terminal posts 260, upper plastic pieces 220, sealing rings 230, and connecting pieces 250.

[0089] Please refer to the following: Figure 5a , Figure 5b and Figure 5c , Figure 5a yes Figure 3The diagram shows an angled structural schematic of one structure of the top cover 100 of the top cover assembly 200. Figure 5b yes Figure 5a The diagram shows the structure of the top cover 100 from another angle. Figure 5c yes Figure 5a The diagram shows the structure of the top cover 100 at another angle.

[0090] The top cover 100 may include a main body 70, an explosion-proof hole 30, an injection hole 40, and a first reinforcing structure 50a. The main body 70 may include a top cover body 10 and a first connecting portion 20. The first connecting portion 20 protrudes from the top cover body 10. The explosion-proof hole 30 is located in the first connecting portion 20 and penetrates the first connecting portion 20 along its thickness direction. The explosion-proof hole 30 is used to connect to an explosion-proof valve 270. The injection hole 40 is located in the first connecting portion 20 and penetrates the first connecting portion 20 along its thickness direction. The injection hole 40 and the explosion-proof hole 30 are spaced apart along the length direction (X direction in the figure) of the top cover 100 and are used to inject electrolyte into the battery cell 310. The first reinforcing structure 50a is recessed in the first connecting portion 20. The recessed direction of the first reinforcing structure 50a relative to the first connecting portion 20 is opposite to the protruding direction of the first connecting portion 20 relative to the top cover body 10. The first reinforcing structure 50a is also located between the explosion-proof hole 30 and the liquid injection hole 40, and is spaced apart from the explosion-proof hole 30 and the liquid injection hole 40 in the length direction of the top cover 100.

[0091] The top cover body 10, the first connecting portion 20, the explosion-proof hole 30, the liquid injection hole 40, and the first reinforcing structure 50a can be connected to form an integral structure. For example, the top cover body 10, the first connecting portion 20, the explosion-proof hole 30, the liquid injection hole 40, and the first reinforcing structure 50a can be an integral structure formed by connecting them through methods such as integral molding. Alternatively, the top cover body 10, the first connecting portion 20, the explosion-proof hole 30, the liquid injection hole 40, and the first reinforcing structure 50a can also be an integral structure formed by connecting them through assembly methods such as welding or bonding.

[0092] In some other embodiments, the top cover 100 may not include the first connecting portion 20. The explosion-proof hole 30, the first reinforcing structure 50a, and the injection hole 40 may be provided on the top cover body 10, provided that the first reinforcing structure 50a is located between the explosion-proof hole 30 and the injection hole 40. This is not strictly limited. Alternatively, the explosion-proof hole 30 and the injection hole 40 may not be provided on the first connecting portion 20 but may be provided on the top cover body 10, provided that the first reinforcing structure 50a is provided on the first connecting portion 20 and is located between the explosion-proof hole 30 and the injection hole 40. This is not strictly limited.

[0093] In the embodiments of this application, the protruding direction of the first connecting portion 20 relative to the top cover body 10 may face away from the battery cell 310, and the recessed direction of the first reinforcing structure 50a relative to the first connecting portion 20 may face towards the battery cell 310. Alternatively, the protruding direction of the first connecting portion 20 relative to the top cover body 10 may face towards the battery cell 310, and the recessed direction of the first reinforcing structure 50a relative to the first connecting portion 20 may face away from the battery cell 310.

[0094] The structure of the top cover assembly 200 will be described below using the case where "the first connecting part 20 protrudes away from the cell 310 relative to the top cover body 10, and the first reinforcing structure 50a is oriented towards the cell 310 relative to the recessed direction of the first connecting part 20", but this is not a limitation.

[0095] Please refer to the following: Figure 5a , Figure 5b , Figure 5c and Figure 6 , Figure 6 It is along Figure 5c A schematic cross-sectional view of the top cover 100 obtained by cutting along the cutting line AA shown.

[0096] The main body 70 and the top cover body 10 can extend along the X direction. The ratio of the length (i.e., the dimension of the main body 70 along the X direction) to the width D6 (i.e., the dimension of the main body 70 along the Y direction) of the main body 70 is greater than 4. That is, the ratio of the length (i.e., the dimension of the top cover body 10 along the X direction) to the width (i.e., the dimension of the top cover body 10 along the Y direction) of the top cover body 10 can be greater than 4. It is understandable that when the length and width of the top cover body 10 are large, the top cover 100 is more prone to deformation along its length, which in turn pulls on the explosion-proof valve 270, causing deformation of the explosion-proof valve 270. When the battery cell 310 experiences thermal runaway, this can lead to abnormal opening of the explosion-proof valve 270, posing a safety hazard to the battery. Therefore, in the embodiments of this application, the ratio of the length to the width of the top cover body 10 is greater than 4, that is, when the ratio of the length to the width of the battery cell 310 is greater than 4, setting the first reinforcing structure 50a on the top cover body 10 helps to control the thermal expansion deformation behavior of the top cover 100, and can effectively avoid the situation where the top cover 100 is deformed due to temperature changes and pulls the explosion-proof valve 270.

[0097] The top cover body 10 may include a third surface 11 and a fourth surface 12. The third surface 11 and the fourth surface 12 are disposed opposite to each other in the thickness direction (Z direction in the figure) of the top cover 100. The third surface 11 is away from the battery cell 310. The fourth surface 12 is towards the battery cell 310.

[0098] The top cover body 10 may be provided with a first through hole 13. The first through hole 13 can penetrate the third surface 11 and the fourth surface 12 of the top cover body 10. That is, the first through hole 13 penetrates the top cover body 10 along the thickness direction (Z direction in the figure). The first through hole 13 is used to install the pole post 260. The shape of the first through hole 13 can be adapted to the shape of the pole post 260. There can be one or more first through holes 13. When there are multiple first through holes 13, the multiple first through holes 13 are spaced apart in the length direction of the top cover body 10. Each first through hole 13 is used to install one pole post 260.

[0099] For example, the first through hole 13 can be hexagonal in shape. There can be two first through holes 13. The two first through holes are located at opposite ends of the top cover body 10 along its length. One first through hole 13 is used to install the positive terminal. The other first through hole 13 is used to install the negative terminal.

[0100] The first connecting portion 20 may protrude from the top cover body 10. Specifically, the first connecting portion 20 protrudes from the third surface 11 of the top cover body 10 and is recessed from the fourth surface 12 of the top cover body 10. It is understood that the recessed arrangement of the first connecting portion 20 relative to the fourth surface 12 of the top cover body 10 not only reduces material usage and saves costs but also reduces space occupation. In some other embodiments, a portion of the first connecting portion 20 may be located within the top cover body 10, and a portion of the first connecting portion 20 may protrude from the third surface 11 of the top cover body 10. The embodiments of this application do not strictly limit the connection relationship between the first connecting portion 20 and the top cover body 10, only requiring that at least a portion of the first connecting portion 20 protrudes from the third surface 11 of the top cover body 10. The first connecting portion 20 can be formed by stamping or by welding.

[0101] The first connecting portion 20 may include a first surface 21 and a second surface 22. The first surface 21 and the second surface 22 are disposed opposite to each other in the thickness direction of the top cover 100. The first surface 21 is away from the battery cell 310 and is disposed on the same side as the third surface 11 of the top cover body 10. The first surface 21 may be disposed parallel to the third surface 11 of the top cover body 10. The second surface 22 faces the battery cell 310 and is disposed on the same side as the fourth surface 12 of the top cover body 10. The second surface 22 may be disposed parallel to the fourth surface 12 of the top cover body 10. The second surface 22 of the first connecting portion 20 may be located between the first surface 21 of the first connecting portion 20 and the third surface 11 of the top cover body 10. Alternatively, the second surface 22 of the first connecting portion 20 may be flush with the third surface 11 of the top cover body 10. Alternatively, the second surface 22 of the first connecting portion 20 may be located between the third surface 11 and the fourth surface 12 of the top cover body 10. The distance between the first surface 21 and the second surface 22 of the first connecting portion 20 may be equal to the thickness of the top cover body 10.

[0102] Furthermore, in the length direction of the top cover 100, the length of the first connecting portion 20 may be less than the length of the top cover body 10. In the width direction of the top cover 100 (Y direction in the figure), the width of the first connecting portion 20 may be less than or equal to the width of the top cover body 10.

[0103] One possible implementation, such as Figure 6 As shown, the first connecting portion 20 may include a first sub-portion 23 and a second sub-portion 24. The first sub-portion 23 may extend along the X direction, and the extension direction of the first sub-portion 23 may be parallel to the extension direction of the top cover body 10. The first sub-portion 23 may also be raised relative to the top cover body 10 along the Z direction. The first sub-portion 23 includes the first surface 21 and the second surface 22 described above. The second sub-portion 24 is disposed around the outer edge of the first sub-portion 23 and connects the outer edge of the first sub-portion 23 and the top cover body 10. Exemplarily, the second sub-portion 24 may be bent to connect the outer edge of the first sub-portion 23 and the top cover body 10.

[0104] Please refer to the following: Figure 5a , Figure 5b , Figure 5c and Figure 7 , Figure 7 It is along Figure 5c Another cross-sectional view of the top cover 100 obtained by cutting along section line BB.

[0105] An explosion-proof hole 30 is provided in the first connecting portion 20 and can penetrate the first surface 21 and the second surface 22 of the first connecting portion 20. The explosion-proof hole 30 may include a first hole 31, a second hole 32, and a third hole 33. The first hole 31, the second hole 32, and the third hole 33 are coaxially arranged and connected. Along the thickness direction of the first connecting portion 20 (Z direction in the figure), the second hole 32 connects the first hole 31 and the third hole 33. The opening of the first hole 31 at the end away from the second hole 32 is located on the first surface 21 of the first connecting portion 20. The opening of the third hole 33 at the end away from the second hole 32 is located on the second surface 22 of the first connecting portion 20. The cross-sectional width of the second hole 32 along the thickness direction of the top cover 100 is smaller than the cross-sectional width of the first hole 31 along the thickness direction of the top cover 100. The cross-sectional width of the second hole 32 along the thickness direction of the top cover 100 is smaller than the cross-sectional width of the third hole 33 along the thickness direction of the top cover 100. The first hole 31 is used to accommodate and connect to the explosion-proof valve protection plate 280. The third hole 33 is used to accommodate and connect to the explosion-proof valve 270. The shape of the explosion-proof hole 30 can be adapted to the shape of the explosion-proof valve protector 280 and the explosion-proof valve 270. For example, the explosion-proof hole 30 can be elliptical or square.

[0106] In one possible implementation, the top cover 100 may include a retaining wall 60. The retaining wall 60 is connected to the first surface 21 of the first connecting portion 20 and surrounds the outer edge of the explosion-proof hole 30. That is, the retaining wall 60 is annular and surrounds the explosion-proof hole 30. The retaining wall 60 may form a fourth hole 61. The fourth hole 61 is coaxially arranged with and communicates with the explosion-proof hole 30. For example, as... Figure 7 As shown, the fourth hole 61 of the retaining wall 60 can communicate with the first hole 31 of the explosion-proof hole 30. The cross-sectional width of the fourth hole 61 along the thickness direction of the top cover 100 is equal to the cross-sectional width of the first hole 31 along the thickness direction of the top cover 100. Figure 7 In the middle, the dotted line serves as the boundary. Below the dotted line is the first hole 31 of the explosion-proof hole 30, and above the dotted line is the fourth hole 61 of the retaining wall 60.

[0107] Understandably, by setting a retaining wall 60 at the outer edge of the explosion-proof hole 30 of the top cover 100, the structural strength of the top cover 100 around the explosion-proof hole 30 can be increased, reducing the deformation of the top cover 100 under high temperature or high pressure conditions, thereby improving the safety of the battery 300. The retaining wall 60 can also prevent external objects from accidentally contacting the explosion-proof valve 270 and the explosion-proof valve protection plate 280, reducing the possibility of misoperation and ensuring that the valve will not be accidentally opened.

[0108] In the embodiments of this application, the injection hole 40 is located in the first connecting portion 20 and extends through the first surface 21 and the second surface 22 of the first connecting portion 20 along its thickness direction (Z direction in the figure). The injection hole 40 may be spaced apart from the explosion-proof hole 30.

[0109] Please refer to the following: Figure 5a , Figure 5b , Figure 5c and Figure 6 The first reinforcing structure 50a can be recessed into the first connecting portion 20. The opening of the first reinforcing structure 50a is located on the first surface 21 of the first connecting portion 20, and it is recessed into the first connecting portion 20 from the first surface 21. The first reinforcing structure 50a can be formed in one piece by stamping or by welding.

[0110] Understandably, in related technologies, a vacuum is required to create a negative pressure inside the battery during electrolyte injection, allowing the electrolyte to enter through the injection tube under this negative pressure. However, the negative pressure generated during battery injection can easily deform the top cover. If this deformation extends to the explosion-proof valve, it can pull on the valve, causing further deformation and reducing its reliability. This could lead to unstable valve opening or short-side opening, ultimately posing a safety hazard to the battery.

[0111] Therefore, in the embodiments of this application, by providing a first reinforcing structure 50a on the top cover 100, the local strength of the top cover 100 can be increased, the pressure applied to the top cover 100 can be dispersed, the free deformation space of the top cover 100 under force can be limited, and the possibility of deformation of the top cover 100 can be reduced. Furthermore, since the first reinforcing structure 50a is also provided between the injection hole 40 and the explosion-proof hole 30, the strength of the area between the injection hole 40 and the explosion-proof hole 30 of the top cover 100 can be improved. When injection causes deformation of the top cover 100, the deformation area extending from the injection hole 40 to the first reinforcing structure 50a will be blocked, preventing the explosion-proof valve 270 from being pulled, thereby ensuring that the explosion-proof valve 270 will not deform, enhancing the reliability of the explosion-proof valve 270, and preventing the explosion-proof valve 270 from malfunctioning in the event of thermal runaway of the large-capacity battery 300, thus improving the safety performance of the battery 300.

[0112] Furthermore, this application not only provides a first reinforcing structure 50a around the explosion-proof hole 30, but also provides the first reinforcing structure 50a on the first connecting portion 20. The first connecting portion 20 not only enhances the strength of the top cover 100 and disperses stress, but also, combined with the first reinforcing structure 50a having an opposite concave structure, forms a two-stage anti-deformation structure, which can further optimize the stress distribution on the top cover 100, reduce stress concentration, and thus reduce the risk of deformation of the top cover 100 and the explosion-proof valve 270. The retaining wall 60 of the top cover 100 can also serve as an anti-deformation structure to prevent deformation of the top cover 100 and the explosion-proof valve 270, thereby improving the safety of the battery 300.

[0113] Please continue reading. Figure 6In the embodiments of this application, the first reinforcing structure 50a also protrudes from the second surface 22 of the first connecting portion 20. It is understood that by making the first reinforcing structure 50a recessed from the first surface 21 of the first connecting portion 20 and protruding from the second surface 22 of the first connecting portion 20, the recess depth of the first reinforcing structure 50a can be further increased while ensuring the strength of the top cover 100. This helps to avoid the problem of the top cover 100 deforming due to negative pressure during liquid injection, which could then pull on the explosion-proof valve 270 and reduce its reliability.

[0114] The first reinforcing structure 50a may include a first transition portion 51a and a first platform portion 52a. The first platform portion 52a may extend along the X direction, and the extension direction of the first platform portion 52a may be parallel to the extension direction of the second sub-part 24 of the first connecting portion 20 and / or the top cover body 10. The first platform portion 52a may also be recessed relative to the first connecting portion 20 in the opposite direction of the Z direction. The first transition portion 51a is disposed around the outer edge of the first platform portion 52a and connects the outer edge of the first platform portion 52a and the inner edge of the first connecting portion 20. Exemplarily, the first transition portion 51a may be bent and connected to the outer edge of the first platform portion 52a and the inner edge of the first connecting portion 20.

[0115] The first reinforcing structure 50a may include a fifth surface 521 and a sixth surface 522. The fifth surface 521 and the sixth surface 522 are disposed opposite each other in the thickness direction (Z direction shown in the figure) of the first platform portion 52a. The fifth surface 521 faces away from the battery cell 310. The sixth surface 522 faces the battery cell 310. The distance between the fifth surface 521 and the sixth surface 522 may be equal to the thickness of the top cover body 10 along the thickness direction of the top cover 100. That is, the thickness of the first platform portion 52a is equal to the thickness of the top cover body 10.

[0116] In one possible implementation, the sixth surface 522 of the first reinforcing structure 50a may be flush with the fourth surface 12 of the top cover body 10.

[0117] It is understandable that by making the sixth surface 522 of the first reinforcing structure 50a flush with the fourth surface 12 of the top cover body 10, the surface of the first reinforcing structure 50a away from the first connecting part 20 will not protrude relative to the fourth surface of the top cover body 10. This avoids the problem of the first reinforcing structure 50a being too deeply recessed, which could interfere with other internal structures of the battery 300 and cause the battery 300 to fail. This is beneficial for the battery 300 to have better working reliability.

[0118] In this embodiment, the fifth surface 521 of the first reinforcing structure 50a may be flush with the second surface 22 of the first connecting portion 20. In other embodiments, the fifth surface 521 of the first reinforcing structure 50a may be lower than or higher than the second surface 22 of the first connecting portion 20.

[0119] In the embodiments of this application, the ratio of the maximum dimension D5 of the first reinforcing structure 50a along the width direction of the main body 70 to the maximum dimension of the first reinforcing structure 50a along the length direction of the main body 70 is within the range of 1:1 to 3:1 (including the endpoint values ​​of 1:1 and 3:1). The shape of the first reinforcing structure 50a can be rectangular, hexagonal, or circular. That is, the cross-sectional shape of the first reinforcing structure 50a along the thickness direction perpendicular to the top cover 100 can be rectangular, hexagonal, or circular. Of course, the cross-sectional shape of the first reinforcing structure 50a along the thickness direction perpendicular to the top cover 100 is not limited to the shapes listed above; it can also be triangular, pentagonal, rhomboid, trapezoidal, elliptical, or other shapes, without strict limitation.

[0120] The dimensions of the first reinforcing structure 50a will be illustrated below through three specific implementation methods.

[0121] For one possible implementation, please refer to Figure 5c The first reinforcing structure 50a can be rectangular in shape. That is, the cross-sectional shape of the first reinforcing structure 50a along the thickness direction perpendicular to the top cover 100 can be rectangular.

[0122] In this embodiment, such as Figure 5c As shown, the ratio of the length to the width of the first reinforcing structure 50a can be in the range of 1:1 to 3:1 (including the endpoint values ​​of 1:1 and 3:1). The length of the first reinforcing structure 50a is its dimension along the width direction of the main body 70 (i.e., its dimension along the Y direction shown in the figure), and the width of the first reinforcing structure 50a is its dimension along the length direction of the main body 70 (i.e., its dimension along the X direction shown in the figure).

[0123] Alternatively, the ratio of the length to the width of the first reinforcing structure 50a may be within the range of 1:1 to 3:1 (including the endpoint values ​​of 1:1 and 3:1). The length of the first reinforcing structure 50a is its dimension along the length direction of the main body 70 (i.e., its dimension along the X direction shown in the figure), and the width of the first reinforcing structure 50a is its dimension along the width direction of the main body 70 (i.e., its dimension along the Y direction shown in the figure).

[0124] It is understandable that by setting the aspect ratio of the first reinforcing structure 50a within the aforementioned range, the strength of the top cover 100 can be improved, and stress concentration in the length or width direction of the first reinforcing structure 50a can be avoided due to its small size, thus preventing it from becoming a weak point in strength. This allows the first reinforcing structure 50a to have good resistance to deformation without occupying too much space inside the battery 300, thereby giving the top cover 100 good resistance to deformation as well.

[0125] In this embodiment, the length of the first reinforcing structure 50a can be in the range of 20mm-40mm (inclusive of the endpoint values ​​of 20mm and 40mm). The length of the first reinforcing structure 50a is its dimension along the length direction of the main body 70. Alternatively, the length of the first reinforcing structure 50a is its dimension along the width direction of the main body 70. It is understood that by setting the length of the first reinforcing structure 50a within the aforementioned range, the first reinforcing structure 50a can have good resistance to deformation without occupying too much internal space of the battery 300.

[0126] The ratio of the maximum dimension D5 of the first reinforcing structure 50a along the width direction of the main body 70 to the width D6 of the main body 70 can be in the range of 30%-60% (including the endpoint values ​​of 30% and 60%). It can be understood that by setting the maximum dimension D5 of the first reinforcing structure 50a along the width direction of the main body 70 within the aforementioned range, the first reinforcing structure 50a can have good resistance to deformation without occupying too much space inside the battery 300.

[0127] For another possible implementation, please refer to Figure 8a , Figure 8a yes Figure 3 Another structural schematic diagram of the top cover 100 of the top cover assembly 200 shown.

[0128] The first reinforcing structure 50a can be hexagonal in shape. That is, the cross-sectional shape of the first reinforcing structure 50a along the thickness direction perpendicular to the top cover 100 can be hexagonal. In this case, the length and width of the first reinforcing structure 50a also satisfy the relationship and numerical range of the length and width of the first reinforcing structure 50a when the shape of the first reinforcing structure 50a is rectangular (i.e., the cross-sectional shape of the first reinforcing structure 50a along the thickness direction perpendicular to the top cover 100 is rectangular). The difference is that the length of the first reinforcing structure 50a is the maximum dimension of the first reinforcing structure 50a along the width direction of the main body 70 (i.e., the maximum dimension of the first reinforcing structure 50a along the width direction of the main body 70). Figure 8a(As shown in D5). The width of the first reinforcing structure 50a is the maximum dimension of the first reinforcing structure 50a along the length direction of the main body 70. Alternatively, the length of the first reinforcing structure 50a is the maximum dimension of the first reinforcing structure 50a along the length direction of the main body 70. The width of the first reinforcing structure 50a is the maximum dimension of the first reinforcing structure 50a along the width direction of the main body 70.

[0129] For another possible implementation, please refer to Figure 8b , Figure 8b yes Figure 3 Another structural schematic diagram of the top cover 100 of the top cover assembly 200 shown.

[0130] The shape of the first reinforcing structure 50a can also be circular. That is, the cross-sectional shape of the first reinforcing structure 50a along the thickness direction perpendicular to the top cover 100 can be circular. In this case, the length and width of the first reinforcing structure 50a also satisfy the relationship and numerical range of the length and width of the first reinforcing structure 50a when the shape of the first reinforcing structure 50a is rectangular (i.e., the cross-sectional shape of the first reinforcing structure 50a along the thickness direction perpendicular to the top cover 100 is rectangular). The difference is that the length of the first reinforcing structure 50a is the maximum dimension of the first reinforcing structure 50a along the width direction of the main body 70 (i.e., the maximum dimension of the first reinforcing structure 50a along the width direction of the main body 70). Figure 8b (As shown in D5). The width of the first reinforcing structure 50a is the maximum dimension of the first reinforcing structure 50a along the length direction of the main body 70. Alternatively, the length of the first reinforcing structure 50a is the maximum dimension of the first reinforcing structure 50a along the length direction of the main body 70. The width of the first reinforcing structure 50a is the maximum dimension of the first reinforcing structure 50a along the width direction of the main body 70.

[0131] In the embodiments of this application, the first reinforcing structure 50a is located between the injection hole 40 and the explosion-proof hole 30. Along the length of the top cover 100, the distance between the first reinforcing structure 50a and the explosion-proof hole 30 is less than the distance between the injection hole 40 and the explosion-proof hole 30. It is understood that placing the first reinforcing structure 50a closer to the explosion-proof hole 30 can enhance the strength around the explosion-proof hole 30 of the top cover 100, preventing deformation of the top cover 100 due to negative pressure during injection, which could then pull on the explosion-proof valve 270 and affect its normal opening during thermal runaway. This is beneficial for maintaining internal pressure balance within the battery 300.

[0132] The ratio of the distance D1 between the first reinforcing structure 50a and the injection hole 40 to the distance D2 between the first reinforcing structure 50a and the explosion-proof hole 30 is within the range of 3:1 to 7:1 (including the endpoint values ​​of 3:1 and 7:1). It is understandable that setting the ratio of the distance D1 between the first reinforcing structure 50a and the injection hole 40 to the distance D2 between the first reinforcing structure 50a and the explosion-proof hole 30 within the aforementioned range can, on the one hand, sufficiently strengthen the area surrounding the explosion-proof hole 30, preventing negative pressure during injection from causing deformation of the top cover 100, which could then pull on the explosion-proof valve 270 and affect its normal opening in the event of thermal runaway, thus facilitating pressure balance within the battery 300. On the other hand, it also prevents the first reinforcing structure 50a from being too close to the injection hole 40, which could obstruct the flow of electrolyte to the side of the first reinforcing structure 50a during injection, resulting in a slower electrolyte wetting rate on that side.

[0133] Furthermore, in the longitudinal direction of the top cover 100, the distance D2 between the first reinforcing structure 50a and the explosion-proof hole 30 can be in the range of 10mm-30mm (including the endpoint values ​​of 10mm and 30mm).

[0134] It is understandable that the first reinforcing structure 50a is provided on the top cover 100 to prevent excessive deformation in the area of ​​the explosion-proof valve 270. Therefore, the first reinforcing structure 50a cannot be too far from the explosion-proof valve 270. At the same time, considering the manufacturability of the top cover 100, the first reinforcing structure 50a cannot be too close to the explosion-proof valve 270. If the first reinforcing structure 50a is too close to the explosion-proof valve 270, it will cause certain difficulties in providing the first reinforcing structure 50a on the top cover 100. Therefore, in the embodiments of this application, the distance between the first reinforcing structure 50a and the explosion-proof hole 30 is set within the aforementioned range. This avoids both excessive distance leading to poor effectiveness in preventing deformation of the explosion-proof valve 270 and insufficient distance making it difficult to manufacture the first reinforcing structure 50a on the top cover 100, resulting in better reliability.

[0135] Please refer to the following: Figures 5a-8b The top cover 100 may further include a second reinforcing structure 50b. The second reinforcing structure 50b is located on the side of the explosion-proof hole 30 away from the injection hole 40 and is spaced apart from the explosion-proof hole 30. The recessed direction of the second reinforcing structure 50b relative to the first connecting portion 20 is opposite to the protruding direction of the first reinforcing structure 50a relative to the top cover body 10. The general structure of the second reinforcing structure 50b can be referred to the relevant description of the first reinforcing structure 50a, and will not be repeated here.

[0136] Understandably, providing a first reinforcing structure 50a and a second reinforcing structure 50b on the top cover 100 not only prevents deformation of the top cover 100 and the explosion-proof valve 270 due to negative pressure during liquid injection, but also, compared to providing only one first reinforcing structure 50a, provides both a first reinforcing structure 50a and a second reinforcing structure 50b, resulting in more uniform strength of the top cover 100 and greater consistency under stress. This more effectively reduces the degree of deformation of the top cover 100 and the explosion-proof valve 270 caused by thermal runaway of the battery cell 310.

[0137] In the embodiments of this application, the protruding direction of the first connecting portion 20 relative to the top cover body 10 may face away from the battery cell 310, and the recessed direction of the second reinforcing structure 50b relative to the first connecting portion 20 may face towards the battery cell 310. Alternatively, the protruding direction of the first connecting portion 20 relative to the top cover body 10 may face towards the battery cell 310, and the recessed direction of the second reinforcing structure 50b relative to the first connecting portion 20 may face away from the battery cell 310.

[0138] The structure of the top cover assembly 200 will be described below using the case where "the first connecting part 20 protrudes away from the cell 310 relative to the top cover body 10, and the second reinforcing structure 50b is oriented towards the cell 310 relative to the recessed direction of the first connecting part 20", but this is not a limitation.

[0139] Please refer to the following: Figure 5a , Figure 5b , Figure 5c and Figure 6 The second reinforcing structure 50b is recessed relative to the first surface 21 and protrudes relative to the second surface 22. The second reinforcing structure 50b can be formed in one step by stamping or by welding.

[0140] It is understandable that by making the second reinforcing structure 50b recessed relative to the first surface 21 of the first connecting portion 20 and protruding relative to the second surface 22 of the first connecting portion 20, the recess depth of the second reinforcing structure 50b can be further increased while ensuring the strength of the top cover 100. This helps to avoid the problem of the top cover 100 deforming due to negative pressure during liquid injection, which would then pull the explosion-proof valve 270 and reduce its reliability.

[0141] The second reinforcing structure 50b may include a seventh surface 523 and an eighth surface 524. The seventh surface 523 and the eighth surface 524 are disposed opposite each other in the thickness direction (Z direction in the figure) of the second platform portion 52b. The seventh surface 523 faces away from the battery cell 310. The eighth surface 524 (i.e., the surface of the second reinforcing structure 50b facing away from the first connecting portion 20) faces the battery cell 310. The distance between the seventh surface 523 and the eighth surface 524 may be equal to the thickness of the top cover body 10 along the thickness direction of the top cover 100.

[0142] In one possible implementation, the eighth surface 524 of the second reinforcing structure 50b may be flush with the fourth surface 12 of the top cover body 10.

[0143] It is understandable that by making the eighth surface 524 of the second reinforcing structure 50b flush with the fourth surface 12 of the top cover body 10, the surface of the second reinforcing structure 50b away from the first connecting part 20 will not protrude relative to the fourth surface of the top cover body 10. This avoids the problem of the second reinforcing structure 50b being too deeply recessed, which could interfere with other internal structures of the battery 300 and cause the battery 300 to fail. This is beneficial for the battery 300 to have better working reliability.

[0144] In this embodiment, the seventh surface 523 of the second reinforcing structure 50b may be flush with the second surface 22 of the first connecting portion 20. In other embodiments, the seventh surface 523 of the second reinforcing structure 50b may be lower than or higher than the second surface 22 of the first connecting portion 20.

[0145] The second reinforcing structure 50b may include a second transition portion 51b and a second platform portion 52b. The second platform portion 52b may extend in the X direction, and the extension direction of the second platform portion 52b may be parallel to the extension direction of the second sub-part 24 of the first connecting portion 20 and / or the top cover body 10. The second platform portion 52b may also be recessed relative to the first connecting portion 20 in the opposite direction of the Z direction. The second transition portion 51b is disposed around the outer edge of the second platform portion 52b and connects the outer edge of the second platform portion 52b and the inner edge of the first connecting portion 20. The thickness of the second platform portion 52b may be equal to the thickness of the top cover body 10. Exemplarily, the second transition portion 51b may be bent and connected to the outer edge of the second platform portion 52b and the inner edge of the first connecting portion 20.

[0146] The ratio of the maximum dimension D7 of the second reinforcing structure 50b along the width direction of the main body 70 to the maximum dimension of the second reinforcing structure 50b along the length direction of the main body 70 is within the range of 1:1 to 3:1 (including the endpoint values ​​of 1:1 and 3:1). The shape of the second reinforcing structure 50b can be rectangular, hexagonal, or circular. That is, the cross-sectional shape of the second reinforcing structure 50b along the thickness direction perpendicular to the top cover 100 can be rectangular, hexagonal, or circular. Of course, the cross-sectional shape of the second reinforcing structure 50b along the thickness direction perpendicular to the top cover 100 is not limited to the shapes listed above, and can also be triangular, pentagonal, rhomboid, trapezoidal, elliptical, or other shapes, without strict limitation.

[0147] For one possible implementation, please refer to Figure 5c The second reinforcing structure 50b can be rectangular in shape. That is, the cross-sectional shape of the second reinforcing structure 50b along the thickness direction perpendicular to the top cover 100 can be rectangular.

[0148] In this embodiment, such as Figure 5c As shown, the ratio of the length to the width of the second reinforcing structure 50b can be in the range of 1:1 to 3:1 (including the endpoint values ​​of 1:1 and 3:1). The length of the second reinforcing structure 50b is its dimension along the width direction of the main body 70 (i.e., its dimension along the Y direction shown in the figure), and the width of the second reinforcing structure 50b is its dimension along the length direction of the main body 70 (i.e., its dimension along the X direction shown in the figure).

[0149] Alternatively, the ratio of the length of the second reinforcing structure 50b to the width of the second reinforcing structure 50b is within the range of 1:1 to 3:1 (including the endpoint values ​​of 1:1 and 3:1). The length of the second reinforcing structure 50b is its dimension along the length direction of the main body 70 (i.e., its dimension along the X direction shown in the figure), and the width of the second reinforcing structure 50b is its dimension along the width direction of the main body 70 (i.e., its dimension along the Y direction shown in the figure).

[0150] It is understandable that by setting the aspect ratio of the second reinforcing structure 50b within the aforementioned range, the strength of the top cover 100 can be improved, and stress concentration in the length or width direction of the second reinforcing structure 50b can be avoided due to its small size, thus preventing it from becoming a weak point in strength. This allows the second reinforcing structure 50b to have good resistance to deformation without occupying too much space inside the battery 300, thereby giving the top cover 100 good resistance to deformation as well.

[0151] In this embodiment, the length of the second reinforcing structure 50b can be in the range of 20mm-40mm (inclusive of the endpoint values ​​of 20mm and 40mm). The length of the second reinforcing structure 50b is its dimension along the length direction of the main body 70. Alternatively, the length of the second reinforcing structure 50b is its dimension along the width direction of the main body 70. It is understood that by setting the length of the second reinforcing structure 50b within the aforementioned range, it is possible to achieve good deformation resistance without occupying excessive internal space of the battery 300.

[0152] The ratio of the maximum dimension D7 of the second reinforcing structure 50b along the width direction of the main body 70 to the width D6 of the main body 70 can be in the range of 30%-60% (including the endpoint values ​​of 30% and 60%). It is understood that by setting the maximum dimension D7 of the second reinforcing structure 50b along the width direction of the main body 70 within the aforementioned range, the second reinforcing structure 50b can have good resistance to deformation without occupying too much space inside the battery 300.

[0153] For another possible implementation, please refer to Figure 8a The second reinforcing structure 50b can be hexagonal. That is, the cross-sectional shape of the second reinforcing structure 50b along the thickness direction perpendicular to the top cover 100 can be hexagonal. In this case, the length and width of the second reinforcing structure 50b also satisfy the relationship and numerical range of the length and width of the second reinforcing structure 50b when its shape is rectangular (i.e., the cross-sectional shape of the second reinforcing structure 50b along the thickness direction perpendicular to the top cover 100 is rectangular). The difference is that the length of the second reinforcing structure 50b is the maximum dimension of the second reinforcing structure 50b along the width direction of the main body 70 (i.e.,...). Figure 8a (As shown in D7). The width of the second reinforcing structure 50b is the maximum dimension of the second reinforcing structure 50b along the length direction of the main body 70. Alternatively, the length of the second reinforcing structure 50b is the maximum dimension of the second reinforcing structure 50b along the length direction of the main body 70. The width of the second reinforcing structure 50b is the maximum dimension of the second reinforcing structure 50b along the width direction of the main body 70.

[0154] For another possible implementation, please refer to Figure 8bThe second reinforcing structure 50b can also be circular. That is, the cross-sectional shape of the second reinforcing structure 50b along the thickness direction perpendicular to the top cover 100 can be circular. In this case, the length and width of the second reinforcing structure 50b also satisfy the relationship and numerical range of the length and width of the second reinforcing structure 50b when the shape of the second reinforcing structure 50b is rectangular (i.e., the cross-sectional shape of the second reinforcing structure 50b along the thickness direction perpendicular to the top cover 100 is rectangular). The difference is that the length of the second reinforcing structure 50b is the maximum dimension of the second reinforcing structure 50b along the width direction of the main body 70 (i.e., the maximum dimension of the second reinforcing structure 50b along the width direction of the main body 70). Figure 8b (As shown in D7). The width of the second reinforcing structure 50b is the maximum dimension of the second reinforcing structure 50b along the length direction of the main body 70. Alternatively, the length of the second reinforcing structure 50b is the maximum dimension of the second reinforcing structure 50b along the length direction of the main body 70. The width of the second reinforcing structure 50b is the maximum dimension of the second reinforcing structure 50b along the width direction of the main body 70.

[0155] In the embodiments of this application, the distance D4 between the second reinforcing structure 50b and the explosion-proof hole 30 in the length direction of the top cover 100 is in the range of 10mm-30mm.

[0156] It is understandable that the second reinforcing structure 50b is provided on the top cover 100 to prevent excessive deformation in the area of ​​the explosion-proof valve 270. Therefore, the second reinforcing structure 50b cannot be too far from the explosion-proof valve 270. At the same time, considering the manufacturability of the top cover 100, the second reinforcing structure 50b cannot be too close to the explosion-proof valve 270. If the second reinforcing structure 50b is too close to the explosion-proof valve 270, it will cause certain difficulties in providing the second reinforcing structure 50b on the top cover 100. Therefore, in the embodiments of this application, the distance between the second reinforcing structure 50b and the explosion-proof hole 30 is set within the aforementioned range. This ensures that the distance is neither too large, resulting in poor effectiveness in preventing deformation of the explosion-proof valve 270, nor too small, making it difficult to manufacture the second reinforcing structure 50b on the top cover 100, thus achieving better reliability.

[0157] Please see Figure 9a and Figure 9b , Figure 9a yes Figure 3 The diagram shows a structural schematic of the top patch 210 of the top cover assembly 200 at one angle. Figure 9b yes Figure 9a The diagram shows a cross-sectional view of the top patch 210 obtained by cutting along the cutting line CC.

[0158] The top patch 210 covers at least a portion of the top cover 100 and connects to the first surface 21 of the first connecting portion 20 of the top cover 100 and the third surface 11 of the top cover body 10 of the top cover 100. The thickness of the top patch 210 is less than the thickness of the top cover 100. The top patch 210 covers the openings of the first reinforcing structure 50a and / or the second reinforcing structure 50b. There is a gap between the top patch 210 and the first platform portion 52a of the first reinforcing structure 50a and / or the second platform portion 52b of the second reinforcing structure 50b. This gap is the gap between the top patch 210 and the first reinforcing structure 50a and / or the second reinforcing structure 50b, and this gap can add tearable points to the top patch 210. When the top patch 210 needs to be replaced or maintained, it is easier to remove the top patch 210 from the top cover 100 by starting from the position where the top patch 210 covers the first reinforcing structure 50a and / or the second reinforcing structure 50b. This improves the maintenance efficiency of the battery 300 and facilitates the disassembly and recycling of the battery 300. Furthermore, the presence of the first reinforcing structure 50a, the second reinforcing structure 50b, and the first connecting part 20 on the top cover 100 enhances the top cover 100's resistance to deformation, thereby reducing the degree of deformation and arching of the top cover 100 and further preventing the top cover 100 from warping.

[0159] In embodiments of this application, the top patch 210 may include a top patch body 214 and a second connecting portion 215. The second connecting portion 215 protrudes from the top patch body 214. The protrusion direction of the second connecting portion 215 relative to the top patch body 214 is the same as the protrusion direction of the first connecting portion 20 of the top cover 100 relative to the top cover body 10. At least a portion of the first connecting portion 20 of the top cover 100 is located within the second connecting portion 215 of the top patch 210. Alternatively, at least a portion of the second connecting portion 215 of the top patch 210 is located within the first connecting portion 20 of the top cover 100.

[0160] Specifically, the first connecting portion 20 of the top cover 100 protrudes away from the battery cell 310 relative to the top cover body 10. The second connecting portion 215 protrudes away from the battery cell 310 relative to the top patch body 214 (e.g., Figure 9b (As shown). At least a portion of the first connecting portion 20 of the top cover 100 is located within the second connecting portion 215 of the top patch 210. Alternatively, the first connecting portion 20 of the top cover 100 protrudes towards the battery cell 310 relative to the top cover body 10. The second connecting portion 215 protrudes towards the battery cell 310 relative to the top patch body 214. At least a portion of the second connecting portion 215 of the top patch 210 is located within the first connecting portion 20 of the top cover 100.

[0161] The top patch 210 may have a second through hole 211, a fifth hole 212, and an identification hole 213. The second through hole 211 may extend through the top patch 210 along its thickness direction (Z direction in the figure). The second through hole 211 may communicate with the first through hole 13 of the top cover body 10 of the top cover 100 and is used for the pole post 260 to pass through. The second through hole 211 of the top patch 210 may be separated from the pole post 260 by a portion of the upper plastic 220. The inner surface of the second through hole 211 abuts against a portion of the outer peripheral surface of the upper plastic 220. The number of second through holes 211 may be the same as the number of pole posts 260, and may also be one or more. For example, the number of second through holes 211 may be two, and the two second through holes 211 are spaced apart along the length direction (X direction in the figure) of the top patch 210. One of the second through holes 211 is used for the positive polarity pole 260 to pass through, and the other second through hole 211 is used for the negative polarity pole 260 to pass through.

[0162] The fifth hole 212 can penetrate the top patch 210 along its thickness direction. The fifth hole 212 can communicate with the explosion-proof hole 30 of the top cover 100. The cross-sectional width of the fifth hole 212 along the thickness direction of the top cover assembly 200 can be greater than the cross-sectional width of the explosion-proof valve protection plate 280 along the thickness direction of the top cover assembly 200, so as to expose the explosion-proof valve protection plate 280.

[0163] The marking hole 213 can penetrate the top patch 210 along its thickness direction. The marking hole 213 can be spaced apart from the fifth hole 212 along the length direction of the top patch 210. The marking hole 213 is used to expose the marking on the top cover 100.

[0164] For example, the second through hole 211 may be located in the top patch body 214 and penetrate the top patch body 214 along the thickness direction of the top patch body 214. The fifth hole 212 and the marking hole 213 are both located in the second connecting portion 215 and penetrate the top patch body 214 along the thickness direction of the top patch body 214.

[0165] Please refer to the following: Figure 10 and Figure 11 , Figure 10 It is along Figure 3 The diagram shows a cross-sectional view of a portion of the structure of the top cover assembly 200 obtained by cutting along section line DD. Figure 11 yes Figure 3 The diagram shows a structural schematic of the upper plastic 220 of the top cover assembly 200 at an angle.

[0166] The upper plastic body 220 may include an upper plastic body 221 and an upper plastic protrusion 222. The upper plastic body 221 may be connected to the first surface 21 of the first connecting portion 20 of the top cover 100. The upper plastic body 221 may also pass through the second through hole 211 of the top patch 210 and protrude relative to the top patch 210. The upper plastic body 221 is provided with a first mounting groove 2211. The opening of the first mounting groove 2211 is located on the surface of the upper plastic body 221 away from the top patch 210. The first mounting groove 2211 is used for the electrode post 260 to pass through and to accommodate a portion of the electrode post base 261 of the electrode post 260.

[0167] The upper plastic protrusion 222 is fixedly connected to the surface of the upper plastic body 221 near the top cover 100. The upper plastic protrusion 222 can be installed in the first through hole 13 of the top cover body 10 of the top cover 100 and the fifth through hole 241 of the lower plastic 240. The upper plastic protrusion 222 can serve as insulation and is used to separate the terminal 260 from the top cover 100 to prevent the top cover 100 and the terminal 260 from directly contacting each other and causing a short circuit.

[0168] The upper plastic 220 may be provided with a third through hole 223. The third through hole 223 extends through the upper plastic body 221 and the upper plastic protrusion 222 along the thickness direction of the upper plastic 220 (Z direction in the figure). The third through hole 223 is coaxially arranged and connected with the first mounting groove 2211. The third through hole 223 is used to allow the electrode post 260 to pass through and to accommodate a portion of the electrode post body 262 (such as the second body 262b) of the electrode post 260.

[0169] Please refer to the following: Figure 10 and Figure 12 , Figure 12 yes Figure 3 A schematic diagram of the structure of the sealing ring 230 of the top cover assembly 200 at one angle.

[0170] The sealing ring 230 can be fitted onto the pole post 260. Specifically, the sealing ring 230 may have a fourth through hole 231. The fourth through hole 231 penetrates the sealing ring 230 along its thickness direction (Z direction in the figure). The fourth through hole 231 of the sealing ring 230 can be used for the pole post body 262 of the pole post 260 to pass through, and is spaced apart from the outer peripheral surface of the pole post body 262 of the pole post 260. The gap area between the fourth through hole 231 of the sealing ring 230 and the pole post body 262 of the pole post 260 can be used to accommodate the upper plastic protrusion 222 of the upper plastic 220. That is, the sealing ring 230 can be fitted onto the upper plastic protrusion 222 of the upper plastic 220. A portion of the inner surface of the fourth through hole 231 of the sealing ring 230 abuts against a portion of the outer peripheral surface of the upper plastic protrusion 222. The sealing ring 230 also abuts between the top cover 100 and the connecting piece 250. The overlapping portion of the sealing ring 230 and the connecting piece 250 is the compression zone of the sealing ring 230.

[0171] Please refer to the following: Figure 10 and Figure 13 , Figure 13 yes Figure 3 The diagram shows a structural schematic of the lower plastic 240 of the top cover assembly 200 at an angle.

[0172] The lower plastic 240 may have a fifth through hole 241. The fifth through hole 241 penetrates the lower plastic 240 along its thickness direction (Z direction in the figure). The fifth through hole 241 can be used for the electrode body 262 of the electrode post 260 to pass through, and is spaced apart from the outer peripheral surface of the electrode body 262 of the electrode post 260. The gap area between the fifth through hole 241 of the lower plastic 240 and the electrode body 262 of the electrode post 260 can be used to accommodate the upper plastic protrusion 222 of the upper plastic 220 and the sealing ring 230. There is a gap between the inner surface of the fifth through hole 241 and the outer peripheral surface of the sealing ring 230.

[0173] The fifth through hole 241 can be two. The two fifth through holes 241 can be spaced apart along the opposite length of the lower plastic 240 (in the X direction shown in the diagram). One fifth through hole 241 is used for the positive electrode post 260 to pass through. The other fifth through hole 241 is used for the negative electrode post 260 to pass through.

[0174] The lower plastic component 240 can be a one-piece structure. Alternatively, the lower plastic component 240 can be a split structure. Specifically, the lower plastic component 240 may include a first part 242 and a second part 243. The first part 242 and the second part 243 are arranged sequentially along the length direction (X direction in the figure) of the lower plastic component 240. The first part 242 and the second part 243 are detachably connected. The detachable portion of the first part 242 and the second part 243 is as follows: Figure 13 As indicated by the dashed arrow, the first part 242 may include a fifth through hole 241. The second part 243 may include a fifth through hole 241.

[0175] Please refer to the following: Figure 10 and Figure 14 , Figure 14 yes Figure 3 A schematic diagram of the structure of the connecting piece 250 of the top cover assembly 200 at one angle.

[0176] The connecting piece 250 may include a first connecting segment 251 and a second connecting segment 252. The first connecting segment 251 extends along the length direction (X direction in the figure) of the top cover assembly 200. The first connecting segment 251 is used to connect with the terminal post 260. The first connecting segment 251 has a sixth through hole 2511. The sixth through hole 2511 extends through the first connecting segment 251 along its thickness direction. The sixth through hole 2511 is used for the terminal post 260 to pass through and to accommodate a portion of the terminal post body 262 (such as the first body 262a) of the terminal post 260. The inner surface of the sixth through hole 2511 of the first connecting segment 251 abuts against the outer peripheral surface of the terminal post 260. The surface of the first connecting segment 251 away from the lower plastic 240 is flush with the surface of the terminal post 260 facing the cell 310.

[0177] The second connecting segment 252 can be bent and connected to one end of the first connecting segment 251. The second connecting segment 252 extends along the thickness direction (Z direction in the figure) of the top cover assembly 200.

[0178] Please refer to the following: Figure 10 , Figure 15 , Figure 16 and Figure 17 , Figure 15 It is along Figure 3 The diagram shows another cross-sectional view of a portion of the top cover assembly 200 obtained by cutting along section line DD. Figure 16 yes Figure 3 A schematic diagram of one structure of the pole post 260 of the top cover assembly 200 is shown. Figure 17 yes Figure 3 Another structural schematic diagram of the pole post 260 of the top cover assembly 200 shown.

[0179] The pole post 260 may include a pole post base 261 and a pole post body 262. The pole post base 261 is fixedly connected to the pole post body 262. The cross-sectional width of the pole post base 261 along the thickness direction (Z direction in the figure) of the pole post 260 is greater than the cross-sectional width of the pole post body 262 along the thickness direction of the pole post 260.

[0180] For one possible implementation, please refer to Figure 10 and Figure 16 The pole body 262 may include a first body 262a and a second body 262b. The first body 262a is fixedly connected to one end of the second body 262b. The end of the second body 262b away from the first body 262a is fixedly connected to the pole base 261. That is, the second body 262b is connected between the pole base 261 and the first body 262a. The cross-sectional width of the first body 262a along the thickness direction of the pole 260 is smaller than the cross-sectional width of the second body 262b along the thickness direction of the pole 260.

[0181] Understandably, designing the pole body 262 into two parts of different sizes allows for better installation of the top cover assembly 200, such as the top cover 100, upper plastic 220, and lower plastic 240, into their corresponding parts, preventing misalignment. Furthermore, the pole base 261 is larger than the pole body 262, effectively preventing the pole 260 from slipping off.

[0182] In this embodiment, a portion of the electrode base 261 of the electrode post 260 protrudes relative to the upper plastic 220. Another portion of the electrode base 261 of the electrode post 260 is located in the first mounting groove 2211 and the third through hole 223 of the upper plastic 220. A portion of the outer peripheral surface of the electrode base 261 of the electrode post 260 abuts against the inner peripheral surface of the first mounting groove 2211 of the upper plastic 220. The second body 262b of the electrode post 260 may be located in the third through hole 223 of the upper plastic 220, the first through hole 13 of the top cover 100, the fourth through hole 231 of the sealing ring 230, and the fifth through hole 241 of the lower plastic 240. The first body 262a of the electrode post 260 may be located in the third through hole 223 of the upper plastic 220, the fourth through hole 231 of the sealing ring 230, the fifth through hole 241 of the lower plastic 240, and the sixth through hole 2511 of the connecting piece 250.

[0183] That is, the upper plastic 220 is fitted onto part of the pole post base 261 and part of the second body 262b of the pole post 260. The inner peripheral surface of the first mounting groove 2211 of the upper plastic 220 abuts against part of the outer peripheral surface of the pole post base 261 of the pole post 260. The inner peripheral surface of the upper plastic protrusion 222 of the upper plastic 220 abuts against part of the outer peripheral surface of the second body 262b of the pole post 260. The top cover 100 is fitted onto the second body 262b of the pole post 260 and is separated from the second body 262b of the pole post 260 by the upper plastic protrusion 222 of the upper plastic 220. The inner surface of the first through hole 13 of the top cover 100 abuts against the outer peripheral surface of the upper plastic protrusion 222.

[0184] A sealing ring 230 is fitted onto a portion of the second body 262b and a portion of the first body 262a of the pole post 260, and is separated from the portion of the second body 262b and the portion of the first body 262a of the pole post 260 by an upper plastic protrusion 222. The inner surface of the fourth through hole 231 of the sealing ring 230 abuts against a portion of the outer peripheral surface of the upper plastic protrusion 222. A lower plastic 240 is fitted onto a portion of the second body 262b and a portion of the first body 262a of the pole post 260. The fifth through hole 241 of the lower plastic 240 is separated from the portion of the second body 262b and the portion of the first body 262a of the pole post 260 by the sealing ring 230 and the upper plastic protrusion 222 of the upper plastic 220. There is a gap between the inner surface of the fifth through hole 241 of the lower plastic 240 and the outer peripheral surface of the sealing ring 230. A connecting piece 250 is fitted onto the first body 262a of the pole post 260. The inner surface of the sixth through hole 2511 of the connecting piece 250 abuts against the outer peripheral surface of the first body 262a of the pole post 260.

[0185] For another possible implementation, please refer to [reference needed]. Figure 15 , Figure 17 , Figure 18a and Figure 18b , Figure 18a yes Figure 3 The diagram shows a structural schematic of the filler 290 of the top cover assembly 200 at one angle. Figure 18b yes Figure 3 A schematic diagram of the structure of the filler 290 of the top cover assembly 200 at an angle.

[0186] In this embodiment, the contents that are the same as those in the previous embodiment will not be repeated. The difference from the previous embodiment is that the cross-sectional width of the pole body 262 along the thickness direction (Z direction in the figure) of the top cover assembly 200 gradually decreases from the direction away from the pole base 261.

[0187] The top cover assembly 200 may include a filler 290. The filler 290 is located between the pole post 260 and the upper plastic 220, and between the pole post 260 and the connecting piece 250. The filler 290 may include a first filler portion 291, a second filler portion 292, and a third filler portion 293. In the thickness direction (Z direction shown in the figure) of the top cover assembly 200, the second filler portion 292 is located between the first filler portion 291 and the third filler portion 293. One end of the second filler portion 292 is connected to the first filler portion 291. The other end of the second filler portion 292 is connected to the third filler portion 293. The first filler portion 291 and the third filler portion 293 may be spaced apart in the thickness direction of the top cover assembly 200. The second filler portion 292 may be connected between the inner edge of the first filler portion 291 and the outer edge of the third filler portion 293, and bendably connected to both the first filler portion 291 and the third filler portion 293.

[0188] The first filling portion 291 is located between the pole base 261 of the pole post 260 and the upper plastic body 221 of the upper plastic 220. The surface of the first filling portion 291 away from the second filling portion 292 abuts against the surface of the pole base 261 near the pole body 262. The surface of the first filling portion 291 near the second filling portion 292 abuts against the bottom wall of the first mounting groove 2211 of the upper plastic 220. The second filling portion 292 is located between the pole body 262 of the pole post 260 and the upper plastic protrusion 222 of the upper plastic 220, and between the pole body 262 of the pole post 260 and the connecting piece 250. The second filling portion 292 can abut against the upper plastic protrusion 222 of the upper plastic 220, the pole body 262 of the pole post 260, and the connecting piece 250. The third filling portion 293 is located between the pole body 262 of the pole post 260 and the connecting piece 250. The third filling part 293 is also located in the sixth through hole 2511 of the connecting piece 250. The inner peripheral surface of the third filling part 293 abuts against the pole body 262 of the pole 260. The outer peripheral surface of the third filling part 293 abuts against the inner surface of the sixth through hole 2511 of the connecting piece 250. The bottom surface of the third filling part 293 is flush with the surface of the first connecting section 251 of the connecting piece 250 away from the lower plastic 240.

[0189] Specifically, the first filling portion 291 may have a sixth hole 2911. The sixth hole 2911 penetrates the first filling portion 291 along its thickness direction. The inner circumferential surface of the sixth hole 2911 abuts against the outer circumferential surface of the pole body 262. The filling member 290 may have a second mounting groove 294. Along the thickness direction of the filling member 290 (Z direction in the figure), the second mounting groove 294 can penetrate the second filling portion 292 and part of the third filling portion 293. The opening of the second mounting groove 294 faces the pole base 261. The second mounting groove 294 is coaxially arranged and connected to the sixth hole 2911 of the first filling portion 291. The shape of the second mounting groove 294 can be adapted to the shape of the pole base 261. The inner circumferential surface of the second mounting groove 294 abuts against the outer circumferential surface of the pole body 262.

[0190] In this embodiment, a portion of the electrode base 261 of the electrode post 260 protrudes relative to the upper plastic 220. Another portion of the electrode base 261 of the electrode post 260 is located in the first mounting groove 2211 of the upper plastic 220. The electrode body 262 of the electrode post 260 is located in the second mounting groove 294 of the filler 290, the third through hole 223 of the upper plastic 220, the first through hole 13 of the top cover 100, the fourth through hole 231 of the sealing ring 230, the fifth through hole 241 of the lower plastic 240, and the sixth through hole 2511 of the connecting piece 250.

[0191] That is, the upper plastic 220 is fitted onto part of the pole post base 261 and pole post body 262 of the pole post 260. The third through hole 223 of the upper plastic 220 is separated from the pole post base 261 by the first filling part 291 and from the pole post body 262 by the second filling part 292. In the thickness direction (Z direction in the figure) of the top cover assembly 200, part of the inner peripheral surface of the first mounting groove 2211 of the upper plastic 220 abuts against the outer peripheral surface of the pole post base 261, and part of the inner peripheral surface abuts against the outer peripheral surface of the first filling part 291. The inner peripheral surface of the upper plastic protrusion 222 of the upper plastic 220 abuts against the outer peripheral surface of the second filling part 292.

[0192] A top cover 100 is fitted onto the pole body 262 of the pole post 260. The first through hole 13 of the top cover 100 is separated from the pole body 262 of the pole post 260 by the upper plastic protrusion 222 of the upper plastic 220 and the second filling portion 292 of the filler 290. The inner surface of the first through hole 13 of the top cover 100 abuts against the outer peripheral surface of the upper plastic protrusion 222. A sealing ring 230 is fitted onto the pole body 262 of the pole post 260. The fourth through hole 231 of the sealing ring 230 is separated from the pole body 262 of the pole post 260 by the upper plastic protrusion 222 of the upper plastic 220, a portion of the second filling portion 292 of the filler 290, and a portion of the third filling portion 293 of the filler 290. The inner surface of the fourth through hole 231 of the sealing ring 230 abuts against a portion of the outer peripheral surface of the upper plastic protrusion 222.

[0193] The lower plastic 240 is fitted onto the pole body 262 of the pole 260. The fifth through hole 241 of the lower plastic 240 is separated from the pole body 262 by the sealing ring 230, the upper plastic protrusion 222 of the upper plastic 220, a portion of the second filling portion 292 of the filler 290, and a portion of the third filling portion 293. A gap exists between the inner surface of the fifth through hole 241 of the lower plastic 240 and the outer peripheral surface of the sealing ring 230. The connecting piece 250 is fitted onto the pole body 262 of the pole 260 and is separated from the pole body 262 by the third filling portion 293 of the filler 290. The inner surface of the sixth through hole 2511 of the connecting piece 250 abuts against the outer peripheral surface of the third filling portion 293 of the filler 290.

[0194] 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 top cover, characterized in that, The top cover includes: The main body includes a top cover body and a first connecting part, the first connecting part protruding from the top cover body; An explosion-proof hole is provided in the first connecting part and penetrates the first connecting part along the thickness direction of the first connecting part. The explosion-proof hole is used to connect with an explosion-proof valve. The injection hole is located at the first connecting portion and extends through the first connecting portion along its thickness direction; the injection hole and the explosion-proof hole are spaced apart. A first reinforcing structure is recessed in the first connecting portion. The recessed direction of the first reinforcing structure relative to the first connecting portion is opposite to the protruding direction of the first connecting portion relative to the top cover body. The first reinforcing structure is located between the explosion-proof hole and the liquid injection hole, and is spaced apart from both the explosion-proof hole and the liquid injection hole.

2. The top cover according to claim 1, characterized in that, The first connecting portion protrudes away from the battery cell relative to the top cover body, and the first reinforcing structure is recessed towards the battery cell relative to the first connecting portion; or... The first connecting portion protrudes towards the battery cell relative to the top cover body, and the first reinforcing structure is recessed away from the battery cell relative to the first connecting portion.

3. The top cover according to claim 2, characterized in that, The top cover also includes a second reinforcing structure, which is recessed in the first connecting portion and located on the side of the explosion-proof hole away from the liquid injection hole. The second reinforcing structure is spaced apart from the explosion-proof hole, and the recessed direction of the second reinforcing structure relative to the first connecting portion is opposite to the protruding direction of the first connecting portion relative to the top cover body.

4. The top cover according to claim 3, characterized in that, The first connecting portion protrudes away from the battery cell relative to the top cover body, and the second reinforcing structure is recessed towards the battery cell relative to the first connecting portion; or... The first connecting portion protrudes towards the battery cell relative to the top cover body, and the second reinforcing structure is recessed away from the battery cell relative to the first connecting portion.

5. The top cover according to claim 4, characterized in that, The first connecting portion includes a first surface and a second surface, the first surface and the second surface being disposed opposite to each other in the thickness direction of the top cover, and the second surface being oriented toward the battery cell; The first reinforcing structure is recessed relative to the first surface and protrudes relative to the second surface; and / or, The second reinforcing structure is recessed relative to the first surface and protrudes relative to the second surface.

6. The top cover according to claim 4, characterized in that, The top cover body includes a third surface and a fourth surface, the third surface and the fourth surface are disposed opposite to each other in the thickness direction of the top cover, and the fourth surface is used to face the battery cell; The surface of the first reinforcing structure facing away from the first connecting portion is flush with the fourth surface; and / or, The surface of the second reinforcing structure that faces away from the first connecting portion is flush with the fourth surface.

7. The top cover according to any one of claims 1-6, characterized in that, The first reinforcing structure includes a first transition portion and a first platform portion. The first platform portion is disposed parallel to the top cover body. The first transition portion is disposed around the outer edge of the first platform portion and connects the outer edge of the first platform portion and the inner edge of the first connecting portion. The thickness of the first platform portion is equal to the thickness of the top cover body; and / or, The first connecting portion includes a first sub-part and a second sub-part. The first sub-part is arranged parallel to the top cover body, and the second sub-part is arranged around the outer edge of the first sub-part and connected between the outer edge of the first sub-part and the top cover body. The thickness of the first sub-part is equal to the thickness of the top cover body.

8. The top cover according to any one of claims 3-6, characterized in that, The second reinforcing structure includes a second transition portion and a second platform portion. The second platform portion is arranged parallel to the top cover body. The second transition portion is arranged around the outer edge of the second platform portion and is connected to the outer edge of the second platform portion and the inner edge of the first connecting portion. The thickness of the second platform portion is equal to the thickness of the top cover body.

9. The top cover according to any one of claims 1-6, characterized in that, The ratio of the distance between the first reinforcing structure and the injection hole to the distance between the first reinforcing structure and the explosion-proof hole is in the range of 3:1 to 7:

1.

10. The top cover according to any one of claims 1-6, characterized in that, The ratio of the length to the width of the main body is greater than 4.

11. The top cover according to any one of claims 3-6, characterized in that, The ratio of the maximum dimension of the first reinforcing structure along the width direction of the main body to the maximum dimension of the first reinforcing structure along the length direction of the main body is in the range of 1:1 to 3:1; and / or, The ratio of the maximum dimension of the second reinforcing structure along the width direction of the main body to the maximum dimension of the second reinforcing structure along the length direction of the main body is in the range of 1:1 to 3:

1.

12. The top cover according to any one of claims 3-6, characterized in that, The ratio of the length to the width of the first reinforcing structure is within the range of 1:1 to 3:1, wherein the length of the first reinforcing structure is its dimension along the width direction of the main body, and the width of the first reinforcing structure is its dimension along the length direction of the main body; and / or, The ratio of the length to the width of the second reinforcing structure is in the range of 1:1 to 3:1, wherein the length of the second reinforcing structure is the dimension of the second reinforcing structure along the width direction of the main body, and the width of the second reinforcing structure is the dimension of the second reinforcing structure along the length direction of the main body.

13. The top cover according to any one of claims 3-6, characterized in that, The length of the first reinforcing structure is in the range of 20mm-40mm, wherein the length of the first reinforcing structure is the dimension of the first reinforcing structure along the width direction of the main body, or the length of the first reinforcing structure is the dimension of the first reinforcing structure along the length direction of the main body; and / or, The length of the second reinforcing structure is in the range of 20mm-40mm, wherein the length of the second reinforcing structure is the dimension of the second reinforcing structure along the width direction of the main body, or the length of the second reinforcing structure is the dimension of the second reinforcing structure along the length direction of the main body.

14. The top cover according to any one of claims 3-6, characterized in that, The maximum dimension of the first reinforcing structure along the width direction of the body is in the range of 30%-60% of the width of the body; and / or, The maximum dimension of the second reinforcing structure along the width direction of the main body is in the range of 30%-60% of the width of the main body.

15. The top cover according to any one of claims 3-6, characterized in that, Along the length of the top cover, the distance between the first reinforcing structure and the explosion-proof hole is in the range of 10mm-30mm; and / or, Along the length of the top cover, the distance between the second reinforcing structure and the explosion-proof hole is in the range of 10mm-30mm.

16. The top cover according to any one of claims 3-6, characterized in that, The first reinforcing structure, the second reinforcing structure, and the first connecting portion are formed by stamping.

17. A top cover assembly, characterized in that, The top cover assembly includes an explosion-proof valve and a top cover as described in any one of claims 1-16, wherein the explosion-proof valve is connected to the explosion-proof hole.

18. The top cover assembly according to claim 17, characterized in that, The top cover assembly also includes a top patch that is attached to the top cover and covers the first reinforcing structure.

19. The top cover assembly according to claim 18, characterized in that, The top patch includes a top patch body and a second connecting part. The second connecting part protrudes from the top patch body, and the protrusion direction of the second connecting part relative to the top patch body is the same as the protrusion direction of the first connecting part relative to the top cover body. At least a portion of the first connecting portion is located within the second connecting portion, or at least a portion of the second connecting portion is located within the first connecting portion.

20. A battery, characterized in that, The battery includes a cell, a housing, and a top cover assembly as described in any one of claims 17-19, the top cover assembly being connected to the housing and enclosing the housing to form a receiving space, the cell being located within the receiving space.

21. An energy storage device, characterized in that, The energy storage device includes the battery as described in claim 20.

Images