Top cover assembly, battery cell and battery pack

Abstract

The utility model relates to battery technical field provides a top cap subassembly, electric core and battery package, and top cap subassembly includes: top cap body, pole, boss, lower plastic, lower insulating part and connecting piece, the pole is connected with the pole lug electricity of electric core through connecting piece, the boss is connected in one side of top cap body and protrudes outward, and the boss is suitable for with the box body support connection of battery package, the boss is spaced apart with first through -hole, the boss includes support platform and insulating platform, and the inner wall of support platform is equipped with the insulating platform, and the position of insulating platform away from support platform forms the inner chamber, and the inner chamber is used for accommodating pole lug and connecting piece, lower plastic is equipped with first clamping portion, lower insulating part includes insulating plate body and second clamping portion, and second clamping portion is equipped with one side of insulating plate body towards top cap body, and first clamping portion and second clamping portion clamping cooperation. The utility model avoids the setting tear pole lug of pole group to occur the shaking, and has improved the safety performance of electric core.

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, the top cover body, and the lower plastic, which wastes the space inside the cell. Due to the small contact area between the lower plastic and the electrode assembly, the effect of fixing the electrode assembly is poor. 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 pole group and the top cover assembly and the lower plastic for bending of the pole tabs, resulting in low battery cell capacity and poor fixation of the pole group.

[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 supported and connected to the battery pack housing. Along the length direction of the top cover body, the boss is spaced apart from the first through hole. The boss includes a support platform and an insulating platform. The insulating platform is disposed on the inner wall of the support platform, and an inner cavity is formed at the position of the insulating platform away from the support platform. The inner cavity is used to accommodate the electrode tab and the connecting piece. The lower plastic is located on the side of the top cover body facing the electrode tab, and the lower plastic has a first snap-fit ​​portion; The lower insulating component includes an insulating plate and a second snap-fit ​​portion. The insulating plate is located on the side of the lower plastic away from the top cover body. The side of the insulating plate away from the lower plastic is adapted to abut against the electrode assembly of the battery cell. The second snap-fit ​​portion is located on the side of the insulating plate facing the top cover body. The first snap-fit ​​portion and the second snap-fit ​​portion engage in a snap-fit ​​cooperation.

[0006] According to the present invention, a top cover assembly is provided, wherein the lower plastic end is provided with a snap-fit ​​groove, and the groove opening end of the snap-fit ​​groove faces the top cover body; The bottom of the snap-fit ​​groove is provided with a snap-fit ​​hole. The first snap-fit ​​part is located on the side of the snap-fit ​​hole. The second snap-fit ​​part passes through the snap-fit ​​hole and is bent toward the first snap-fit ​​part to snap with the first snap-fit ​​part.

[0007] According to the present invention, a top cover assembly is provided, wherein the second snap-fit ​​portion includes an elastic rib and a snap hook; The elastic rib is connected to the insulating plate and extends along the height direction of the top cover body, and the hook is attached to the free end of the elastic rib.

[0008] According to the top cover assembly provided by this utility model, along the width direction of the top cover body, the engagement length between the hook and the first snap-fit ​​part is W, which satisfies: 0.35mm≤W≤1.2mm; And / or, along the height direction of the top cover body, the height of the elastic rib is H, satisfying: 1.0mm≤H≤3.5mm.

[0009] According to the present invention, a top cover assembly is provided, wherein the lower plastic is provided with a second through hole in the area corresponding to the boss, the lower insulating member has a through hole, the second through hole and the through hole are disposed opposite to each other and both extend along the length direction of the top cover body; The electrode tab passes through the through hole and the second through hole and extends into the inner cavity.

[0010] According to the top cover assembly provided by this utility model, the distance between the electrode lug and the inner wall of the through hole along the width direction of the top cover body is D, which satisfies: 0.5mm≤D≤3.6mm.

[0011] According to the present invention, a top cover assembly is provided, wherein the lower insulating member further has an impregnation hole; The wetting hole extends along the length of the top cover body.

[0012] According to the present invention, a top cover assembly is provided, wherein the wetting holes are arranged in a racetrack shape, and there are multiple wetting holes; One of the wetting holes is located beside the through hole, and the remaining wetting holes are located between the second snap-fit ​​part and the through hole, and are spaced apart along the length of the top cover body.

[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 feature protrusions along the length of the top cover body on the sides of the terminals. These protrusions not only enhance the structural strength of the top cover assembly, thereby improving the mechanical strength of the battery cell, but also increase the surface area of ​​the top cover body, thus increasing the heat dissipation area and the bonding area with the thermally conductive layer. This improves the heat dissipation efficiency of the battery cell, controls its operating temperature, and enhances its safety performance. Furthermore, by providing support and insulation platforms on the protrusions, the inner cavity formed by the support platform can accommodate bent electrode tabs and connecting pieces, improving the production yield of the top cover assembly. Additionally, by providing a lower insulation component between the lower plastic and the electrode assembly, and by providing a first snap-fit ​​portion in the lower plastic and a second snap-fit ​​portion in the lower insulation component, the lower plastic and the lower insulation component can be tightly connected. The lower insulation component increases the stress-bearing area of ​​the electrode assembly, improving its fixation effect, preventing the electrode assembly from shaking and tearing the electrode tabs, and enhancing 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 one of the three-dimensional structural schematic diagrams of the top cover assembly provided by this utility model.

[0018] Figure 2 This is a three-dimensional structural diagram of the lower insulating component provided by this utility model.

[0019] Figure 3 This is a three-dimensional structural diagram of the assembly of the lower plastic and lower insulating parts with the electrode tab provided by this utility model.

[0020] Figure 4 This is a cross-sectional view of the lower plastic and lower insulating parts provided by this utility model after assembly with the electrode tab.

[0021] Figure 5 This is the second three-dimensional structural schematic diagram of the top cover assembly provided by this utility model.

[0022] Figure 6 This is a bottom view of the top cover assembly provided by this utility model.

[0023] Figure 7 This utility model provides Figure 6 AA sectional view.

[0024] Figure 8 This is a three-dimensional structural diagram of the battery cell provided by this utility model.

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

[0026] Figure 10 This is the second cross-sectional view of the battery cell provided by this utility model.

[0027] Figure label: 1. Top cover assembly; 11. Top cover body; 12. Pole post; 13. Boss; 14. Connecting piece; 15. Lower plastic; 16. Connecting block; 17. Lower insulating component; 131. Support platform; 132. Insulating platform; 151. First snap-fit ​​part; 152. Snap-fit ​​groove; 153. Snap-fit ​​hole; 171. Insulating plate; 172. Second snap-fit ​​part; 173. Through hole; 174. Impregnation hole; 1721. Elastic rib; 1722. Hook; 2. Electrode group; 21. Electrode ear; 3. Shell; 100. Battery cells. Detailed Implementation

[0028] 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.

[0029] 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.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] The following is combined Figures 1 to 10The top cover assembly, battery cell, and battery pack provided in this embodiment will be described in detail through specific implementation methods and application scenarios.

[0034] 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, a lower plastic part 15, a lower insulating part 17, and a connecting piece 14.

[0035] The top cover body 11 has a first through hole that penetrates the top cover body 11.

[0036] 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.

[0037] 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. 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 support platform 131 and an insulating platform 132. The insulating platform 132 is located on the inner wall of the support platform 131, so that the position of the insulating platform 132 away from the support platform 131 forms an inner cavity, which is used to accommodate the tab 21 and the connecting piece 14.

[0038] The lower plastic 15 is located on the side of the top cover body 11 facing the tab 21, and the lower plastic 15 is provided with a first snap-fit ​​part 151.

[0039] The lower insulating member 17 includes an insulating plate 171 and a second snap-fit ​​portion 172. The insulating plate 171 is located on the side of the lower plastic 15 away from the top cover body 11. The side of the insulating plate 171 away from the lower plastic 15 is adapted to abut against the electrode group 2 of the battery cell 100. The second snap-fit ​​portion 172 is located on the side of the insulating plate 171 facing the top cover body 11. The first snap-fit ​​portion 151 and the second snap-fit ​​portion 172 are snap-fitted together.

[0040] 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.

[0041] 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.

[0042] Specifically, the boss 13 can be a frustum of a cylinder, a frustum of a cone, or a curved surface; there are no specific limitations on this.

[0043] like Figure 9 As shown, the top cover assembly 1 in this embodiment also includes a connecting piece 14. 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 is bent and extends into the inner cavity and is connected to the tab 21. The connecting piece 14 is arranged in a "Z" shape to ensure that the two ends connected to the pole post 12 and the tab 21 are arranged in parallel.

[0044] 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.

[0045] And, as Figure 10 As shown, the boss 13 in this embodiment includes a support platform 131 and an insulating platform 132. Both the support platform 131 and the insulating platform 132 are platform-shaped and form an inner cavity by covering the top cover body 11 to accommodate the bent electrode tab 21 and the connecting piece 14. The side of the support platform 131 facing away from the electrode tab 21 is used for supporting connection with the battery pack housing. The insulating platform 132 is used to isolate the support platform 131 from the electrode tab 21 and the connecting piece 14 in the inner cavity to prevent short circuit between the electrode tab 21 and the connecting piece 14. In this embodiment, by separately setting the boss 13 and the top cover body 11, and integrating the support platform 131 and the insulating platform 132 into one piece, the boss 13 can be directly welded to the top cover body 11 to achieve assembly of the boss 13 and the top cover body 11. In this embodiment, the inner walls of the support platform 131 and the insulating platform 132 together form the inner cavity. Since an insulating platform 132 is integrally provided on the inner wall of the support platform 131, there is no need to consider the insulation treatment between the boss 13 and the tab 21 when installing the boss 13 and the top cover body 11, which simplifies the installation steps of the top cover assembly 1 and improves the installation efficiency of the top cover assembly 1.

[0046] Specifically, the support platform 131 and the insulating platform 132 can be heat-fused together into a single structure, or they can be bonded together with an adhesive layer. The support platform 131 can be a metal part, such as an aluminum alloy part. The insulating platform 132 can be a plastic part.

[0047] 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.

[0048] Furthermore, the top cover assembly 1 in this embodiment also includes a lower insulating member 17, which is sandwiched between the lower plastic 15 and the electrode group 2. Since space is reserved between the lower plastic 15 and the electrode group 2 to provide bending space for the electrode tab 21, the contact between the electrode group 2 and the lower plastic 15 is not compacted. In this embodiment, the lower insulating member 17 abuts against the electrode group 2 on the side facing it. Along the length of the top cover body 11, the electrode group 2 and the lower insulating member 17 are both attached and supported, resulting in a large contact area between the electrode group 2 and the lower insulating member 17. Because the lower insulating member 17 is connected to the lower plastic 15, the contact area between the electrode group 2 and the top cover assembly 1 is increased, improving the fixing effect of the electrode group 2. During the use of the battery cell 100, when subjected to external forces such as vibration, the electrode group 2 is firmly fixed to the top cover assembly 1, preventing the electrode tab 21 from tearing due to movement of the electrode group 2 and improving the safety performance of the battery cell 100.

[0049] like Figure 6 and Figure 7 As shown, in order to improve the connection strength between the lower plastic 15 and the lower insulating component 17, this embodiment uses a snap-fit ​​connection between the lower plastic 15 and the lower insulating component 17. When assembling the lower plastic 15 and the lower insulating component 17, the first snap-fit ​​portion 151 is inserted into the second snap-fit ​​portion 172, forming a robust connection structure. This restricts the relative movement of the lower insulating component 17 and the lower plastic 15, and makes installation simple and easy.

[0050] Specifically, the lower insulating component 17 can be a plastic component.

[0051] The top cover assembly 1 provided by this utility model, by providing a protrusion 13 on the side of the electrode post 12 along the length direction of the top cover body 11, not only enhances the structural strength of the top cover assembly 1 through the protrusion 13, thereby improving the mechanical strength of the battery cell 100, but also increases the surface area of ​​the top cover body 11 through the protrusion 13, 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, controlling the operating temperature of the battery cell 100, and improving the safety performance of the battery cell 100. Furthermore, by providing a support platform 131 and an insulating platform on the protrusion 13, 132. The inner cavity formed by the support platform 131 can accommodate the bent electrode tab 21 and connecting piece 14, and can also improve the production yield of the top cover assembly 1. Furthermore, by setting a lower insulating member 17 between the lower plastic 15 and the electrode group 2, and by setting a first snap-fit ​​part 151 on the lower plastic 15 and a second snap-fit ​​part 172 on the lower insulating member 17, the lower plastic 15 and the lower insulating member 17 can be tightly connected. The lower insulating member 17 increases the force-bearing area of ​​the electrode group 2, improves the fixing effect of the electrode group 2, prevents the electrode group 2 from shaking and tearing the electrode tab 21, and improves the safety of the battery cell 100.

[0052] like Figure 6 and Figure 7 As shown, the lower plastic 15 of this embodiment has a snap-fit ​​groove 152 at its end, and the groove opening of the snap-fit ​​groove 152 faces the top cover body 11.

[0053] The bottom of the slot 152 is provided with a snap-fit ​​hole 153. The first snap-fit ​​part 151 is located on the side of the snap-fit ​​hole 153. The second snap-fit ​​part 172 passes through the snap-fit ​​hole 153 and is bent toward the first snap-fit ​​part 151 to snap-fit ​​with the first snap-fit ​​part 151.

[0054] Understandably, in order to ensure that the first snap-fit ​​portion 151 and the second snap-fit ​​portion 172 are both within the height range of the lower plastic 15 and the lower insulating member 17 when they snap together, this embodiment provides a snap-fit ​​groove 152 at the end of the lower plastic 15 to accommodate the snap-fit ​​structure of the first snap-fit ​​portion 151 and the second snap-fit ​​portion 172.

[0055] It should be noted that in this embodiment, the second snap-fit ​​portion 172 abuts against the side of the top cover body 11 away from the boss 13 to enhance the stability of the snap-fit ​​structure.

[0056] During assembly, the second snap-fit ​​part 172 extends into the snap-fit ​​hole 153 and engages with the first snap-fit ​​part 151 in the snap-fit ​​groove 152.

[0057] like Figure 6 and Figure 7 As shown, the second snap-fit ​​portion 172 in this embodiment includes an elastic rib 1721 and a snap hook 1722.

[0058] The elastic rib 1721 is connected to the insulating plate 171 and extends along the height direction of the top cover body 11. The hook 1722 is located at the free end of the elastic rib 1721.

[0059] Understandably, the elastic rib 1721 is made of an elastic element and is capable of elastic deformation. The first snap-fit ​​portion 151 includes a flange protruding from the bottom of the snap-fit ​​groove 152. The mounting groove formed by the snap hook 1722 can accommodate the flange, so that the flange and the snap hook 1722 are tightly snapped together, thereby realizing the snap-fit ​​engagement of the first snap-fit ​​portion 151 and the second snap-fit ​​portion 172.

[0060] During assembly, an external force is applied to make the elastic rib 1721 first contact the edge of the first locking part 151, forcing the elastic rib 1721 to undergo elastic deformation and bend inward. When the flange is fully inserted into the hook 1722, the elastic rib 1721 rebounds, making the locking surface of the hook 1722 fit tightly against the bearing surface of the flange, thereby achieving locking and fixing of the two parts.

[0061] like Figure 6 and Figure 7 As shown, along the width direction of the top cover body 11, the engagement length between the hook 1722 and the first snap-fit ​​portion 151 in this embodiment is W, which satisfies: 0.35mm≤W≤1.2mm.

[0062] Understandably, in order to ensure the engagement strength between the first snap-fit ​​portion 151 and the snap hook 1722, and to ensure that the shape of the snap hook 1722 and the first snap-fit ​​portion 151 is not too large and exceeds the accommodating range of the snap-fit ​​groove 152, the engagement length of the snap hook 1722 and the first snap-fit ​​portion 151 in this embodiment needs to meet a certain range.

[0063] Specifically, the engagement length between the hook 1722 and the first engaging part 151 can be 0.35mm, 0.775mm, or 1.2mm.

[0064] like Figure 6 and Figure 7 As shown, along the height direction of the top cover body 11, the height of the elastic rib 1721 in this embodiment is H, which satisfies: 1.0mm≤H≤3.5mm.

[0065] Understandably, the height of the elastic rib 1721 needs to be compatible with the height of the first snap-fit ​​portion 151 protruding from the snap-fit ​​hole 153, and also needs to form a snap-fit ​​structure with the snap hook 1722 to lock the first snap-fit ​​portion 151. In this embodiment, the height H of the elastic rib 1721 needs to meet a certain range.

[0066] Specifically, the height H of the elastic rib 1721 can be 1.0mm, 2.25mm, or 3.5mm.

[0067] like Figure 9 As shown, in this embodiment, the lower plastic 15 is provided with a second through hole in the area corresponding to the boss 13, and the lower insulating member 17 has a through hole 173. The second through hole and the through hole 173 are arranged opposite to each other and both extend along the length direction of the top cover body 11. The tab 21 passes through the through hole 173 and the second through hole and extends into the inner cavity.

[0068] Understandably, the tabs 21 of the electrode assembly 2 need to pass through the lower insulating member 17 and the lower plastic member 15, and be bent before being welded to the connecting piece 14. In this embodiment, a second through hole is provided in the lower plastic member 15, and a through hole 173 is provided in the lower insulating member 17. Both the second through hole and the through hole 173 are strip-shaped holes. Along the height direction of the top cover body 11, the tabs 21 pass through the through hole 173 and the second through hole in sequence, extending into the inner cavity and being welded to the connecting piece 14.

[0069] like Figure 4 As shown, along the width direction of the top cover body 11, the distance between the tab 21 and the inner wall of the through hole 173 in this embodiment is D, which satisfies: 0.5mm≤D≤3.6mm.

[0070] Understandably, the electrode assembly 2 abuts against the lower insulator 17. To prevent the electrode tab 21 from shaking, the width of the through hole 173 is slightly wider than the width of the electrode tab 21. The distance between the electrode tab 21 and the inner wall of the through hole 173 needs to meet a certain range. If it is too wide, the electrode tab 21 will shake strongly relative to the through hole 173. If it is too narrow, the through hole 173 will rub against the electrode tab 21, affecting the electrode tab 21's insertion into the inner cavity.

[0071] Specifically, the distance D between the tab 21 and the inner wall of the through hole 173 can be 0.5mm, 2.05mm, or 3.6mm.

[0072] like Figure 5 and Figure 6 As shown, the lower insulating member 17 in this embodiment also has an impregnation hole 174; the impregnation hole 174 extends along the length direction of the top cover body 11.

[0073] Understandably, since the lower insulating member 17 covers the electrode group 2, in order to prevent the lower insulating member 17 from obstructing the electrolyte and causing dead zones or excessively long wetting cycles, this embodiment provides a wetting hole 174 on the lower insulating member 17. The wetting hole 174 extends along the length direction of the top cover body 11, so that the electrolyte can be wetted through the wetting hole 174.

[0074] like Figure 6 As shown, the wetting holes 174 in this embodiment are arranged in a racetrack shape, and there are multiple wetting holes 174.

[0075] One of the wetting holes 174 is located beside the through hole 173, and the remaining wetting holes 174 are located between the second snap-fit ​​part 172 and the through hole 173, and are spaced apart along the length of the top cover body 11.

[0076] Understandably, the racetrack-shaped wetting holes 174 have a large flow area, which better guides the fluidity of the electrolyte. In order to improve the wetting flow of the electrolyte in the lower insulating member 17, this embodiment provides a plurality of wetting holes 174 on the lower insulating member 17.

[0077] One of the wetting holes 174 is located beside the through hole 173, and the remaining multiple wetting holes 174 are located between the second snap-fit ​​part 172 and the through hole 173, so as to ensure that the wetting holes 174 are evenly distributed along the length direction of the top cover body 11, so that the lower insulating member 17 can allow the electrolyte to flow and wet along the length direction of the top cover body 11.

[0078] Secondly, such as Figure 8 , Figure 9 and Figure 10 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.

[0079] 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.

[0080] 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.

[0081] 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.

[0082] 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 cell 100. Furthermore, a support platform 131 and an insulating platform 132 are provided on the boss 13 and are integrated into one piece, eliminating the need for additional insulation structures. This improves the assembly efficiency of the boss 13 and the top cover body 11. A lower insulating member 17 is also provided between the lower plastic 15 and the pole group 2. By providing a first snap-fit ​​part 151 on the lower plastic 15 and a second snap-fit ​​part 172 on the lower insulating member 17, the lower plastic 15 and the lower insulating member 17 can be tightly connected. The lower insulating member 17 increases the stress-bearing area of ​​the pole group 2, improves the fixing effect of the pole group 2, prevents the pole group 2 from shaking and tearing the pole tab 21, and improves the safety of the cell 100.

[0083] Thirdly, this embodiment provides a battery pack, including: a busbar, a housing, and the battery cell 100 as described above.

[0084] 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.

[0085] 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.

[0086] 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.

[0087] 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.

[0088] 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.

[0089] 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 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 supported and connected to the battery pack housing. Along the length direction of the top cover body, the boss is spaced apart from the first through hole. The boss includes a support platform and an insulating platform. The insulating platform is disposed on the inner wall of the support platform, and an inner cavity is formed at the position of the insulating platform away from the support platform. The inner cavity is used to accommodate the electrode tab and the connecting piece. The lower plastic is located on the side of the top cover body facing the electrode tab, and the lower plastic has a first snap-fit ​​portion; The lower insulating component includes an insulating plate and a second snap-fit ​​portion. The insulating plate is located on the side of the lower plastic away from the top cover body. The side of the insulating plate away from the lower plastic is adapted to abut against the electrode assembly of the battery cell. The second snap-fit ​​portion is located on the side of the insulating plate facing the top cover body. The first snap-fit ​​portion and the second snap-fit ​​portion engage in a snap-fit ​​cooperation.

2. The top cover assembly according to claim 1, characterized in that, The lower plastic part has a snap-fit ​​groove at its end, with the groove opening facing the top cover body; The bottom of the snap-fit ​​groove is provided with a snap-fit ​​hole. The first snap-fit ​​part is located on the side of the snap-fit ​​hole. The second snap-fit ​​part passes through the snap-fit ​​hole and is bent toward the first snap-fit ​​part to snap with the first snap-fit ​​part.

3. The top cover assembly according to claim 2, characterized in that, The second snap-fit ​​part includes an elastic rib and a snap hook; The elastic rib is connected to the insulating plate and extends along the height direction of the top cover body, and the hook is attached to the free end of the elastic rib.

4. The top cover assembly according to claim 3, characterized in that, Along the width direction of the top cover body, the engagement length between the hook and the first snap-fit ​​part is W, which satisfies: 0.35mm≤W≤1.2mm; And / or, along the height direction of the top cover body, the height of the elastic rib is H, satisfying: 1.0mm≤H≤3.5mm.

5. The top cover assembly according to claim 1, characterized in that, The lower plastic part has a second through hole in the area corresponding to the boss, and the lower insulating part has a through hole. The second through hole and the through hole are arranged opposite to each other and both extend along the length direction of the top cover body. The electrode tab passes through the through hole and the second through hole and extends into the inner cavity.

6. The top cover assembly according to claim 5, characterized in that, Along the width direction of the top cover body, the distance between the electrode lug and the inner wall of the through hole is D, which satisfies: 0.5mm≤D≤3.6mm.

7. The top cover assembly according to claim 5, characterized in that, The lower insulating element also has an impregnation hole; The wetting hole extends along the length of the top cover body.

8. The top cover assembly according to claim 7, characterized in that, The impregnation holes are arranged in a racetrack shape, and there are multiple impregnation holes; One of the wetting holes is located beside the through hole, and the remaining wetting holes are located between the second snap-fit ​​part and the through hole, and are spaced apart along the length of the top cover body.

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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