Top cover assembly, battery cell and battery pack

Abstract

The utility model relates to battery technical field provides a top cover subassembly, electric core and battery package, above -mentioned top cover subassembly includes: top cover body, pole, boss and connecting piece, top cover body forms with the first through -hole of going through top cover body, pole is worn in the first through -hole, and is electrically connected with the pole lug of electric core through the connecting piece, the boss is connected in one side of top cover body and is along the height direction of top cover body and is outwardly convex, the boss is suitable for with the box body support connection of battery package, along the length direction of top cover body, the boss is spaced apart with the first through -hole, the boss includes the side wall and lid body subassembly, the side wall is surrounded in one side of top cover body and is away from the pole lug, and the lid body subassembly covers sets up in the open end of side wall to form the inner chamber, and the inner chamber is used for accommodating the pole lug and connecting piece, wherein, the lid body subassembly includes the cover plate and insulating plate, and the insulating plate sets up in one side of cover plate and is towards the pole lug, the top cover subassembly of the utility model avoids the short circuit of cover plate and pole lug and connecting piece, and the safety performance of electric core is improved.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a top cover assembly, a battery cell, and a battery pack. Background Technology

[0002] The battery pack includes a housing and battery modules assembled inside the housing. Each battery module consists of multiple cells, and the terminals of the cells are electrically connected through a busbar. The housing provides physical support and protection for the battery modules. Each cell includes a housing, a top cover assembly, and an electrode assembly. The electrode assembly is located within a cavity formed by the housing and the top cover assembly, and the terminals pass through the top cover assembly and are electrically connected to the tabs of the electrode assembly.

[0003] Currently, in order to provide bending space for the tabs, sufficient height needs to be reserved between the electrode assembly and the top cover body, which wastes the space inside the cell. Furthermore, the cell only contacts other structures in the cell module through the terminal post. When the upper surface of the cell is subjected to force, the terminal post is directly subjected to force, which increases the risk of short circuit and results in low structural strength. Utility Model Content

[0004] This utility model provides a top cover assembly, a battery cell, and a battery pack to solve the problems in the prior art where the top cover assembly only bears the force through the poles, resulting in low strength of the battery cell, and the space reserved between the top cover assembly and the pole group for bending of the tabs, resulting in low battery cell capacity.

[0005] To solve the above-mentioned technical problems, this application is implemented as follows: In a first aspect, this utility model provides a top cover assembly, comprising: The top cover body has a first through hole penetrating the top cover body; The electrode post passes through the first through hole and is electrically connected to the electrode tab of the battery cell through a connecting piece; A boss is connected to one side of the top cover body and protrudes outward along the height direction of the top cover body. The boss is adapted to be connected to the battery pack housing for support. Along the length direction of the top cover body, the boss is spaced apart from the first through hole. The boss includes a side wall and a cover assembly. The side wall surrounds the side of the top cover body away from the electrode tab. The cover assembly covers the opening end of the side wall to form an inner cavity for accommodating the electrode tab and the connecting piece. The cover assembly includes a cover plate and an insulating plate, with the insulating plate disposed on the side of the cover plate facing the tab.

[0006] According to the present invention, in a top cover assembly, along the height direction of the top cover body, the side of the cover plate facing away from the insulating plate is lower than the top surface of the side wall.

[0007] According to the present invention, a top cover assembly is provided in which the inner side of the side wall is inclined along the height direction of the top cover body, and the cross-sectional area of ​​the side wall gradually increases from the end away from the cover assembly toward the end close to the cover assembly. The sidewall has an angle α relative to the vertical direction, satisfying: 25°≤α≤55°.

[0008] According to the present invention, the connection depth between the side wall and the cover assembly along the height direction of the cover body is D, which satisfies 0.6mm≤D≤1.2mm.

[0009] According to the present invention, the thickness of the cover plate is T, which satisfies: 1.2mm≤T≤2.0mm; The thickness of the sidewall is t, which satisfies: 0.8mm≤t≤1.5mm.

[0010] According to the present invention, a top cover assembly further includes: a connecting piece; The connecting piece extends along the length of the top cover body. One end of the connecting piece is connected to the pole post, and the other end of the connecting piece extends into the inner cavity. The pole tab extends into the inner cavity from the height direction of the top cover body and bends and extends towards the width direction of the top cover body to fit with the connecting piece.

[0011] According to the present invention, a top cover assembly further includes: a lower plastic layer; The lower plastic is located on the side of the top cover body facing the electrode ear, and the lower plastic is attached to the side wall corresponding to the position of the inner cavity and is arranged circumferentially along the inner wall of the side wall.

[0012] According to the present invention, a top cover assembly is provided in which the side of the insulating plate away from the cover plate abuts against the side of the lower plastic facing the cover plate.

[0013] Secondly, this utility model provides a battery cell, comprising: an electrode assembly, a housing, and a top cover assembly as described in any of the preceding claims; The housing has an opening, the top cover assembly is disposed in the opening and surrounds the housing to form a receiving cavity, the electrode assembly is disposed in the receiving cavity, and the electrode assembly is electrically connected to the top cover assembly through electrode tabs and connecting pieces.

[0014] Thirdly, this utility model provides a battery pack, including: a busbar, a housing, and the battery cells as described above; The housing forms a receiving cavity, and multiple battery cells are provided, with the multiple battery cells stacked in the receiving cavity; the busbar is connected to the terminals of the multiple battery cells.

[0015] The top cover assembly, battery cell, and battery pack provided by this utility model have protrusions set on the side of the poles along the length of the top cover body. This not only enhances the structural strength of the top cover assembly and thus improves the mechanical strength of the battery cell, but also increases the surface area of ​​the top cover body, thereby increasing the heat dissipation area of ​​the top cover body and the bonding area with the heat-conducting layer, improving the heat dissipation efficiency of the battery cell and controlling the operating temperature of the battery cell. Furthermore, by setting the protrusions in a hollow and separate manner, the inner cavity formed by the side wall and the cover assembly can not only accommodate the bent electrode tabs and connecting pieces, but also improve the production yield of the top cover assembly. The cover assembly is provided with a cover plate and an insulating plate. The insulating plate avoids short circuits between the cover plate and the electrode tabs and connecting pieces, improving the safety of the battery cell. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a three-dimensional structural diagram of the top cover assembly provided by this utility model.

[0018] Figure 2 This is a three-dimensional structural diagram of the top cover assembly provided by this utility model (excluding the cover body assembly).

[0019] Figure 3 This utility model provides Figure 2 A sectional view.

[0020] Figure 4 This is a cross-sectional view of the cover assembly provided by this utility model.

[0021] Figure 5 This is a three-dimensional structural diagram of the top cover assembly provided by this utility model when the tab is not bent.

[0022] Figure 6 This is a three-dimensional structural diagram of the top cover assembly after the tab is bent, provided by this utility model.

[0023] Figure 7 This is a three-dimensional structural diagram of the battery cell provided by this utility model.

[0024] Figure 8 This is one of the cross-sectional views of the battery cell provided by this utility model.

[0025] Figure 9 This is the second cross-sectional view of the battery cell provided by this utility model.

[0026] Figure label: 1. Top cover assembly; 11. Top cover body; 12. Pole post; 13. Boss; 14. Connecting piece; 15. Lower plastic; 16. Connecting block; 131. Side wall; 132. Cover assembly; 1321. Cover plate; 1322. Insulating plate; 2. Electrode group; 21. Electrode ear; 3. Shell; 100. Battery cells. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0028] In the description of the embodiments of this utility model, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the purpose of clarifying the embodiments of this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this utility model. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0029] In the description of the embodiments of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this utility model according to the specific circumstances.

[0030] In this embodiment of the utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0031] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0032] The following is combined Figures 1 to 9 The top cover assembly, battery cell, and battery pack provided in this embodiment will be described in detail through specific implementation methods and application scenarios.

[0033] Firstly, such as Figure 1 , Figure 2 and Figure 3 As shown, this embodiment provides a top cover assembly 1, including: a top cover body 11, a pole post 12, a boss 13, and a connecting piece 14.

[0034] The top cover body 11 has a first through hole that penetrates the top cover body 11.

[0035] The electrode post 12 passes through the first through hole and is electrically connected to the electrode tab 21 of the battery cell 100 through the connecting piece 14.

[0036] The boss 13 is connected to one side of the top cover body 11 and protrudes outward along the height direction of the top cover body 11. The boss 13 is adapted to be connected to the battery pack housing support. Along the length direction of the top cover body 11, the boss 13 is spaced apart from the first through hole. The boss 13 includes a side wall 131 and a cover assembly 132. The side wall 131 surrounds the side of the top cover body 11 away from the tab 21. The cover assembly 132 covers the opening end of the side wall 131 to form an inner cavity for accommodating the tab 21 and the connecting piece 14.

[0037] The cover assembly 132 includes a cover plate 1321 and an insulating plate 1322, with the insulating plate 1322 disposed on the side of the cover plate 1321 facing the tab 21.

[0038] It is understandable that the length, width, and height of the top cover body 11 are shown in the figure. Figure 1 In this embodiment, a protrusion 13 is provided on the side of the terminal post 12, giving the space on the side of the terminal post 12 a raised structure. The protrusion 13 is used for supporting connection with the battery pack housing. Since the height of the protrusion 13 is higher than the height of the electrode group 2, when the surface of the cell 100 is subjected to external impact, the protrusion 13 can withstand the impact, ensuring that the terminal post 12 is not subjected to external impact. Furthermore, since the protrusion 13 has a certain structural strength, it can support the top cover body 11, preventing short circuits in the cell 100 and improving the mechanical strength of the entire cell pack.

[0039] Meanwhile, when the cells 100 are stacked to form a cell module, the upper surface of the cell 100 can conduct heat dissipation through contact with the heat-conducting layer via the electrode post 12, and also through contact with the heat-conducting layer via the boss 13. Compared with the prior art, where most of the top cover body 11 can only dissipate heat through thermal radiation, the contact heat conduction effect of the boss 13 in this embodiment is better, which is more conducive to the heat dissipation of the cell 100, more conducive to controlling the operating temperature of the cell 100, and extending the service life of the cell 100.

[0040] In this embodiment, the boss 13 is set as a hollow platform with the inner cavity facing the side of the tab 21. The tab 21 and the connecting piece 14 can be accommodated in the inner cavity after bending, thereby reducing the gap height between the pole group 2 and the top cover body 11, increasing the bending space of the tab 21, and thus increasing the capacity of the cell 100.

[0041] Furthermore, in this embodiment, the boss 13 is provided as a separate part, with the side wall 131 surrounding one side of the top cover body 11. The cover assembly 132 is welded and fixed to the side wall 131, and the side wall 131 and the cover assembly 132 together form an inner cavity. Because the boss 13 is provided as a separate part, the dimensions of the side wall 131 and the cover can be reasonably set, making the shape of the boss 13 easier to control, improving the production yield of the top cover assembly 1, and ensuring the structural strength of the top cover assembly 1.

[0042] It should be noted that the battery cell 100 has two terminals 12, namely a positive terminal and a negative terminal. In this embodiment, the top cover assembly 1 has one terminal 12, and the other terminal is located on the cover assembly on the other side of the battery cell 100.

[0043] Furthermore, such as Figure 4As shown, the cover assembly 132 includes a cover plate 1321 and an insulating plate 1322. The cover plate 1321 covers the opening end of the side wall 131, and the insulating plate 1322 is located on the side of the cover plate 1321 facing the tab 21. Since the tab 21 extends into the inner cavity and connects to the connecting piece 14, the distance between the tab 21 and the top wall of the boss 13 is small along the height direction of the top cover body 11. The insulating plate 1322 can isolate the tab 21 from the cover plate 1321, preventing the tab 21 from contacting the cover plate 1321 and causing a short circuit.

[0044] Specifically, the cover plate 1321 and the insulating plate 1322 can be heat-fused together to form a single structure, or they can be bonded together with an adhesive layer. The cover plate 1321 can be a metal part, such as an aluminum alloy part. The insulating plate 1322 can be a plastic plate.

[0045] The top cover assembly 1 provided by this utility model has a protrusion 13 provided on the side of the pole 12 along the length direction of the top cover body 11. This not only enhances the structural strength of the top cover assembly 1 and thus improves the mechanical strength of the battery cell 100, but also increases the surface area of ​​the top cover body 11, thereby increasing the heat dissipation area of ​​the top cover body 11 and the bonding area with the heat-conducting layer, improving the heat dissipation efficiency of the battery cell 100 and controlling the operating temperature of the battery cell 100. Furthermore, by hollowing out the protrusion 13, the inner cavity formed by the side wall 131 and the cover assembly 132 can not only accommodate the bent pole tab 21 and the connecting piece 14, but also improve the production yield of the top cover assembly 1. The cover assembly 132 is provided with a cover plate 1321 and an insulating plate 1322. The insulating plate 1322 avoids short circuits between the cover plate 1321 and the pole tab 21 and the connecting piece 14, thus improving the safety of the battery cell 100.

[0046] like Figure 3 As shown, along the height direction of the top cover body 11, the side of the cover plate 1321 facing away from the insulating plate 1322 in this embodiment is lower than the top surface of the side wall 131.

[0047] Understandably, the cover plate 1321 and the side wall 131 are welded together after assembly, with welding positions along the circumference of the cover plate 1321 and the inner wall of the side wall 131. The cover plate 1321 is lower than the top surface of the side wall 131, allowing the circumferential weld marks of the cover plate 1321 to be accommodated within the space formed by the inner side of the side wall 131 and the top surface of the cover plate 1321, without protruding beyond the top wall, i.e., not exceeding the height range of the boss 13. When the boss 13 is connected to the battery pack housing support, the weld marks of the cover plate 1321 will not affect the insulation structure on the housing, enhancing the safety performance of the battery cell 100.

[0048] like Figure 9As shown, along the height direction of the top cover body 11, the inner side of the side wall 131 in this embodiment is inclined, and the cross-sectional area of ​​the side wall 131 gradually increases from the end away from the cover assembly 132 toward the end closer to the cover assembly 132.

[0049] The side wall 131 has an angle α relative to the vertical direction, satisfying: 25°≤α≤55°.

[0050] Understandably, to ensure easy assembly of the top of the side wall 131 with the cover assembly 132, the inner side of the side wall 131 in this embodiment is inclined, presenting a flared structure. The larger end of the flared opening is located on one side of the cover assembly 132. The assembly and disassembly of the cover assembly 132 relative to the side wall 131 can be quickly coordinated, improving the assembly yield.

[0051] Specifically, the tilt angle α can be 25°, 40°, or 55°.

[0052] like Figure 9 As shown, along the height direction of the top cover body 11, the connection depth between the side wall 131 and the cover assembly 132 in this embodiment is D, which satisfies 0.6mm≤D≤1.2mm.

[0053] Understandably, the inner wall of the side wall 131 and the outer wall of the cover assembly 132 need to be connected and fixed to ensure the structural strength and sealing performance of the boss 13. The connection depth between the side wall 131 and the cover assembly 132 needs to meet a certain range, neither exceeding the height of the side wall 131 nor having a connection area that is too small to affect the connection strength.

[0054] Specifically, the connection depth D can be 0.6mm, 0.9mm, or 1.2mm.

[0055] like Figure 9 As shown, the thickness of the cover plate 1321 in this embodiment is T, which satisfies: 1.2mm≤T≤2.0mm.

[0056] The thickness of sidewall 131 is t, which satisfies: 0.8mm≤t≤1.5mm.

[0057] Understandably, in order to ensure the overall strength of the boss 13, the thickness T of the cover plate 1321 and the thickness t of the side wall 131 in this embodiment need to meet certain ranges. They cannot be too large, affecting the volume of the inner cavity, nor too small, affecting the supporting strength of the boss 13.

[0058] Specifically, the thickness t of the sidewall 131 can be 0.8 mm, 1.15 mm, or 1.5 mm.

[0059] like Figure 5 , Figure 6 and Figure 8 As shown, the top cover assembly 1 in this embodiment also includes a connecting piece 14.

[0060] The connecting piece 14 extends along the length of the top cover body 11. One end of the connecting piece 14 is connected to the pole post 12, and the other end of the connecting piece 14 extends into the inner cavity. The pole tab 21 extends into the inner cavity from the height direction of the top cover body 11 and bends and extends towards the width direction of the top cover body 11 to fit with the connecting piece 14.

[0061] Understandably, in this embodiment, the connecting piece 14 is arranged in a "Z" shape, with one end connected to the pole post 12 and the other end connected to the tab 21. The two ends connected to the pole post 12 and the tab 21 are arranged parallel to each other. When assembling the tab 21 and the connecting piece 14, within the inner cavity of the boss 13, the tab 21 is first inserted vertically into the inner cavity at a 90° angle to the connector, then the tab 21 is bent 90° toward the connecting piece 14 and fitted to it, and then welded. The inner cavity provides bending space for the tab 21 and serves as a accommodating space for the connection position of the connecting piece 14 and the tab 21. The bending and welding of the tab 21 within the inner cavity improves production efficiency.

[0062] like Figure 1 and Figure 9 As shown, the top cover assembly 1 in this embodiment also includes a lower plastic 15.

[0063] The lower plastic 15 is located on the side of the top cover body 11 facing the tab 21. The lower plastic 15 is attached to the side wall 131 at the position corresponding to the inner cavity and is arranged circumferentially along the inner wall of the side wall 131.

[0064] Understandably, in order to avoid short circuits between the tab 21 and the connecting piece 14 and the boss 13, this embodiment provides a lower plastic 15 on one side of the top cover body 11. The lower plastic 15 extends into the inner cavity formed by the inner wall of the side wall 131 at the location of the inner cavity and is arranged around the side wall 131 to avoid short circuits caused by the tab 21 and the connecting piece 14 contacting the side wall 131.

[0065] like Figure 9 As shown, in this embodiment, the side of the insulating plate 1322 facing away from the cover plate 1321 abuts against the side of the lower plastic 15 facing the cover plate 1321.

[0066] Understandably, the end of the lower plastic 15 extending into the inner cavity abuts against the insulating plate 1322. Since the insulating plate 1322 and the cover plate 1321 are connected, and the upper side of the cover plate 1321 needs to be lowered by one end relative to the side wall 131, the abutment between the lower plastic 15 and the insulating plate 1322 facilitates precise control of the installation height of the insulating plate 1322 and the cover plate 1321, allowing the insulating plate 1322 and the cover plate 1321 to be accurately positioned in the height direction of the top cover body 11.

[0067] like Figure 3 As shown, the top cover assembly 1 in this embodiment also includes a connecting block 16.

[0068] The connecting block 16 is located on the side of the top cover body 11 away from the electrode tab 21. The connecting block 16 has a through hole, and the electrode post 12 passes through the through hole and is connected to the connecting block 16.

[0069] It is understood that the connecting block 16 in this embodiment is a strip block, and the through hole is set at the center of symmetry of the strip block. The pole post 12 is connected to the center of symmetry of the strip block through the through hole, which improves the fixing stability of the pole post 12.

[0070] Specifically, the connecting block 16 can be a riveted aluminum block, and the top cover body 11 can be an aluminum plate.

[0071] Secondly, such as Figure 7 , Figure 8 and Figure 9 As shown, this embodiment provides a battery cell 100, including: an electrode group 2, a housing 3, and a top cover assembly 1 as described above.

[0072] The housing 3 has an opening, the top cover assembly 1 is disposed in the opening and surrounds the housing 3 to form a receiving cavity, the pole group 2 is disposed in the receiving cavity, and the pole group 2 is electrically connected to the top cover assembly 1 through the pole tab 21 and the connecting piece 14.

[0073] Specifically, since the battery cell 100 includes a top cover assembly 1, and the specific structure of the top cover assembly 1 is as described in the above embodiments, the battery cell 100 shown in this embodiment includes all the technical solutions of the above embodiments. Therefore, it has at least all the beneficial effects obtained by all the technical solutions of the above embodiments, which will not be described in detail here.

[0074] Understandably, the electrode assembly 2 is installed inside the housing 3, and the top cover assembly 1 is placed over the opening of the housing 3. The electrode assembly 2 is electrically connected to the electrode post 12 of the top cover assembly 1 through the electrode tab 21 to realize the transmission of current. The top cover assembly 1 and the housing 3 constitute the outer shell of the battery cell 100, forming protection for the internal components of the battery cell 100 and being able to withstand a certain amount of external impact.

[0075] In this embodiment, a boss 13 is provided on the top cover body 11. The boss 13 is suitable for connection with the battery pack housing support, which increases the stress-bearing area of ​​the top cover body 11, avoids the pole post 12 being subjected to stress alone, and improves the safety performance of the battery cell 100. Furthermore, the boss 13 is divided into a side wall 131 and a cover assembly 132. The cover assembly 132 includes a cover plate 1321 and an insulating plate 1322. The inner cavity formed by the side wall 131 and the cover assembly 132 can accommodate the bent electrode tab 21 and the connecting piece 14. The insulating plate 1322 can also prevent short circuits between the cover plate 1321 and the electrode tab 21 and the connecting piece 14, thus improving the safety of the battery cell 100.

[0076] Thirdly, this embodiment provides a battery pack, including: a busbar, a housing, and the battery cell 100 as described above.

[0077] The housing forms a receiving cavity, and multiple battery cells 100 are provided, with multiple battery cells 100 stacked in the receiving cavity; the busbar is connected to the terminals 12 of the multiple battery cells 100.

[0078] Specifically, since the battery pack includes a cell 100, and the specific structure of the cell 100 is as described in the above embodiments, the battery pack shown in this embodiment includes all the technical solutions of the above embodiments. Therefore, it has at least all the beneficial effects achieved by all the technical solutions of the above embodiments, which will not be described in detail here.

[0079] Understandably, after the battery cells 100 are grouped together within the receiving cavity, the terminal post 12 of each battery cell 100 is welded to the tap on the busbar. The busbar connects the stacked battery cells 100 into groups, and the tap is fixedly connected to the housing through a heat-conducting layer. Because this embodiment provides a protrusion 13 on the side of the terminal post 12, the overall capacity of the battery pack is increased, thereby improving the performance of the battery pack.

[0080] In traditional battery pack structures, the battery pack relies solely on the casing to withstand external impacts. The casing plate opposite the terminal post 12 has a large area, and if its rigidity is insufficient, it is prone to deformation. To prevent casing deformation from causing compression damage to the busbar and terminal post 12, a large space needs to be reserved between the busbar and the casing in the structural design, and supporting foam needs to be installed between them. Some designs also incorporate concave and convex structures on the casing plate to enhance its rigidity and prevent deformation. However, these measures result in a large gap between the cell 100 and the casing, wasting space. Increasing the casing thickness to increase rigidity would increase the weight of the battery pack, hindering lightweight design.

[0081] To address this, this embodiment provides a boss 13 on the outer surface of the top cover body 11. The boss 13 is used to support and connect with the casing, so that the outer shell of the battery cell 100 itself also serves as a supporting load-bearing component. Under the support of the outer shell, large deformation of the casing can be avoided, thereby reducing the thickness of the casing and the weight of the battery pack. Furthermore, while ensuring that the casing does not cause crush damage to the busbars and terminals 12, the distance between the busbars and the casing can be reduced, thereby increasing the volume of the battery cell 100. This fully utilizes the internal space of the casing, increasing the capacity of the battery cell 100 and the energy density of the entire battery pack.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A top cover assembly, applied to a battery cell, characterized in that, include: The top cover body has a first through hole penetrating the top cover body; The electrode post is inserted through the first through hole and electrically connected to the electrode tab of the battery cell through a connecting piece; A boss is connected to one side of the top cover body and protrudes outward along the height direction of the top cover body. The boss is adapted to be connected to the battery pack housing for support. Along the length direction of the top cover body, the boss is spaced apart from the first through hole. The boss includes a side wall and a cover assembly. The side wall surrounds the side of the top cover body away from the electrode tab. The cover assembly covers the opening end of the side wall to form an inner cavity for accommodating the electrode tab and the connecting piece. The cover assembly includes a cover plate and an insulating plate, with the insulating plate disposed on the side of the cover plate facing the tab.

2. The top cover assembly according to claim 1, characterized in that, Along the height direction of the top cover body, the side of the cover plate opposite to the insulating plate is lower than the top surface of the side wall.

3. The top cover assembly according to claim 1, characterized in that, Along the height direction of the top cover body, the inner side of the side wall is inclined, and the cross-sectional area of ​​the side wall gradually increases from the end away from the cover assembly toward the end closer to the cover assembly. The sidewall has an angle α relative to the vertical direction, satisfying: 25°≤α≤55°.

4. The top cover assembly according to claim 3, characterized in that, Along the height direction of the top cover body, the connection depth between the side wall and the cover assembly is D, which satisfies 0.6mm≤D≤1.2mm.

5. The top cover assembly according to claim 1, characterized in that, The thickness of the cover plate is T, which satisfies: 1.2mm≤T≤2.0mm; The thickness of the sidewall is t, which satisfies: 0.8mm≤t≤1.5mm.

6. The top cover assembly according to claim 1, characterized in that, Also includes: Connecting piece; The connecting piece extends along the length of the top cover body. One end of the connecting piece is connected to the pole post, and the other end of the connecting piece extends into the inner cavity. The pole tab extends into the inner cavity from the height direction of the top cover body and bends and extends towards the width direction of the top cover body to fit with the connecting piece.

7. The top cover assembly according to claim 1, characterized in that, Also includes: Plastic bottom; The lower plastic is located on the side of the top cover body facing the electrode ear, and the lower plastic is attached to the side wall corresponding to the position of the inner cavity and is arranged circumferentially along the inner wall of the side wall.

8. The top cover assembly according to claim 7, characterized in that, The side of the insulating plate facing away from the cover plate abuts against the side of the lower plastic facing the cover plate.

9. A battery cell, characterized in that, include: The electrode assembly, the housing, and the top cover assembly as described in any one of claims 1 to 8; The housing has an opening, the top cover assembly is disposed in the opening and surrounds the housing to form a receiving cavity, the electrode assembly is disposed in the receiving cavity, and the electrode assembly is electrically connected to the top cover assembly through electrode tabs and connecting pieces.

10. A battery pack, characterized in that, include: Busbar, housing, and battery cell as described in claim 9; The housing forms a receiving cavity, and multiple battery cells are provided, with the multiple battery cells stacked in the receiving cavity; the busbar is connected to the terminals of the multiple battery cells.

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