Battery cell

Abstract

The utility model relates to the technical field of battery cells, and provides a battery cell which comprises a shell, a pole core and a top cover structure, the top cover structure comprises a shell sealing cover, a sealing insulating layer and a conducting strip, and a first through hole and a second through hole are formed in the shell sealing cover; the sealing insulation layer is arranged on the side, away from the pole core, of the shell sealing cover and provided with a third through hole communicated with the first through hole, the conducting strip is provided with a boss, and the boss penetrates through the third through hole and is connected with the pole core. The sealing shell cover plays a role in sealing the battery cell, the boss in the conducting strip plays a role in forming a pole, the sealing insulating layer is used for sealing and insulating the sealing shell cover and the conducting strip, the three-layer structure is mutually matched, execution of each function does not interfere with each other, the structural design is simple, the performance is stable, and the comprehensive performance of the battery cell is improved.

Description

Technical Field

[0001] The present application relates to the technical field of battery cells, and in particular to a battery cell. Background Art

[0002] A cylindrical battery cell is generally composed of an outer shell, a top cover structure, and a pole core. The top cover structure is installed on the top of the outer shell, and the pole core is arranged inside the outer shell. In a cylindrical battery cell, the top cover structure generally serves as the positive electrode of the battery cell. On the one hand, the top cover structure needs to be electrically connected to the pole core, and on the other hand, it needs to seal the battery cell. The structural design of the top cover structure has a direct impact on the connection reliability between the top cover structure and the pole core, and the sealing of the top cover structure to the battery cell, thereby affecting the overall performance of the battery cell. The top cover structure in the related art is unreasonable in structural design, resulting in poor overall performance of the battery cell. Utility Model Content

[0003] The present application provides a battery cell that can improve the comprehensive performance of the battery cell.

[0004] The battery cell in the embodiment of the present application includes:

[0005] A housing having a receiving cavity and an opening communicating with the receiving cavity;

[0006] A pole core, disposed in the receiving cavity;

[0007] A top cover structure, the top cover structure seals the opening, the top cover structure comprising:

[0008] A sealing cover, wherein a first through hole and a second through hole are formed on the sealing cover, and the second through hole forms a liquid injection channel;

[0009] a sealing insulating layer, the sealing insulating layer being arranged on a side of the shell cover away from the pole core and having a third through hole communicating with the first through hole;

[0010] and a conductive sheet, wherein the conductive sheet is arranged on a side of the sealing insulating layer away from the pole core, the conductive sheet is formed with a boss, and the boss passes through the third through hole and the first through hole and is connected to the pole core.

[0011] The top cover structure in the embodiments of the present application includes a sealing cover, a sealing insulating layer, and a conductive sheet. The sealing cover can be connected to the outer shell to seal the battery cell. The boss on the conductive sheet can pass through the first through hole and the third through hole and be connected to the electrode core. The boss in the conductive sheet serves to form a pole column. The second through hole can be used as the liquid injection hole of the battery cell, and the sealing insulating layer is used to seal and insulate the sealing cover and the conductive sheet. The three-layer structure cooperates with each other, and the execution of each function does not interfere with each other. The structural design is simple and the performance is stable, which is beneficial to improving the comprehensive performance of the battery cell. In addition, by using the boss to form the pole column, the sealing insulating layer can well wrap around the boss, which can simplify the setting method of the sealing insulating layer on the basis of forming a good seal. The boss can also form a better connection with the electrode core, which can also improve the comprehensive performance of the battery cell.

[0012] Based on the layered structure design of the top cover structure in the embodiments of the present application, the structural design of the battery cell is simple and the performance is stable, which is beneficial to improving the comprehensive performance of the battery cell.

[0013] In a possible implementation manner, the second through hole is located at the central position of the sealing cover, and the first through hole is located on one side of the second through hole, or the first through hole is located at the central position of the sealing cover, and the second through hole is located on one side of the first through hole.

[0014] In a possible implementation manner, the periphery of the third through hole extends into the first through hole, and the inner diameter of the third through hole is smaller than the inner diameter of the first through hole.

[0015] In a possible implementation manner, the length L1 of the periphery of the third through hole extending into the first through hole satisfies the relationship:

[0016] L1≥0.1mm.

[0017] In a possible implementation manner, the boss extends out of the first through hole.

[0018] In a possible implementation manner, the length L2 of the boss extending out of the first through hole satisfies the relationship:

[0019] L2 = 0.05mm to 0.2mm.

[0020] In a possible implementation manner, the sealing insulating layer, the sealing cover, and the conductive sheet form a overlapping section around the vicinity of the first through hole, and the length L3 of the overlapping section satisfies the relationship:

[0021] L3>0.5mm.

[0022] In a possible implementation manner, the sealing and insulating layer includes a sealant film. The sealing and insulating layer forms overflow glue portions at both ends of the overlapping section, an insulating layer is formed between the overflow glue portions, and the thickness of the overflow glue portions is greater than that of the insulating layer.

[0023] In a possible implementation manner, the diameter of the boss is 1 mm to 5 mm, and the height of the boss is 0.1 mm to 0.5 mm;

[0024] And / or, the thickness of the cover of the casing is 0.1 mm to 0.5 mm. The cover of the casing includes a stainless steel layer and a nickel-plated layer, and the thickness of the nickel-plated layer is 0.5 μm to 3 μm;

[0025] And / or, the thickness of the conductive sheet is 0.1 mm to 0.5 mm.

[0026] In a possible implementation manner, the sealing and insulating layer has a fourth through hole communicating with the second through hole, the conductive sheet has a fifth through hole communicating with the second through hole, and the second through hole, the fourth through hole and the fifth through hole are in communication.

[0027] In a possible implementation manner, the boss is a hollow structure, or the boss is a solid structure.

[0028] In a possible implementation manner, the boss forms a flat connecting surface, the pole core has a pole tab in a planar shape, and a surface contact is formed between the boss and the pole tab.

[0029] In a possible implementation manner, the sealing and insulating layer and the conductive sheet extend from one side of the first through hole to the other side of the first through hole and extend to a predetermined length.

[0030] In a possible implementation manner, the conductive sheet includes a first notch, the sealing and insulating layer is provided with a second notch corresponding to the first notch, a second through hole cover is provided on the second through hole, and the projection of the second through hole cover in the thickness direction of the battery cell does not overlap with the projection of the conductive sheet or the sealing and insulating layer in the thickness direction of the battery cell.

[0031] In a possible implementation manner, the pole core includes a positive electrode sheet, a negative electrode sheet and a separator located between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet has a positive pole tab, and the negative electrode sheet has a negative pole tab;

[0032] The positive pole tab is connected to the conductive sheet, and the negative pole tab is connected to the outer casing.

[0033] In a possible implementation manner, the projection of the positive pole tab in the thickness direction of the battery cell does not overlap with the projection of the second through hole cover in the thickness direction of the battery cell.

[0034] In a possible implementation manner, the enclosure cover includes a convex portion extending in a direction away from the pole core, and the second through hole is formed on the convex portion.

[0035] In a possible implementation manner, the end of the sealing insulating layer close to the outer shell extends beyond the end of the conductive sheet close to the outer shell.

[0036] In a possible implementation manner, a first step is provided on one side of the enclosure cover facing the outer shell, and a second step is provided on one side of the outer shell facing the enclosure cover.

[0037] In a possible implementation manner, the pole core has a central through hole, a pole core insulating layer is provided on the upper side of the pole core, the pole core insulating layer is provided with an insulating through hole, and the diameter of the insulating through hole is smaller than the diameter of the central through hole. Description of the Drawings

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0039] Figure 1 Shows a schematic structural diagram of a battery cell provided according to an embodiment of the present application;

[0040] Figure 2 Shows an exploded schematic diagram of a battery cell provided according to an embodiment of the present application;

[0041] Figure 3 Shows a cross-sectional view of a battery cell provided according to an embodiment of the present application;

[0042] Figure 4 Shows a cross-sectional view of another battery cell provided according to an embodiment of the present application;

[0043] Figure 5 Shows a cross-sectional view of yet another battery cell provided according to an embodiment of the present application;

[0044] Figure 6 Shows an exploded schematic diagram of another battery cell provided according to an embodiment of the present application;

[0045] Figure 7 Shows a cross-sectional view of another battery cell provided according to an embodiment of the present application;

[0046] Figure 8Shows an explosion schematic diagram of another kind of battery cell provided according to an embodiment of the present application;

[0047] Figure 9 Shows a cross-sectional view of another kind of battery cell provided according to an embodiment of the present application.

[0048] Reference numerals:

[0049] 100 - Outer shell; 101 - Receiving cavity;

[0050] 200 - Electrode core; 201 - Central through hole; 210 - Positive electrode tab;

[0051] 300 - Top cover structure; 310 - Sealing cover; 320 - Sealing insulating layer; 330 - Conductive sheet; 340 - Second through hole cover; 311 - First through hole; 312 - Second through hole; 313 - Protrusion; 321 - Third through hole; 322 - Fourth through hole; 323 - Glue overflow part; 324 - Insulating layer; 325 - Second notch; 331 - Boss; 332 - Fifth through hole; 333 - First notch;

[0052] 400 - Insulating part;

[0053] 500 - Liquid injection structure;

[0054] 600 - Electrode core insulating layer; 601 - Insulating through hole. Detailed implementation manners

[0055] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Apparently, the described embodiments are some, but not all, of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0056] The outer shell of a cylindrical battery cell is generally designed in a structure with an open upper end. After the electrode core is inserted into the outer shell, the negative electrode tab of the electrode core is connected to the bottom of the outer shell to form the negative electrode of the battery cell at the bottom, and the positive electrode tab of the electrode core needs to be connected to the top cover structure, and the top cover structure is used as the positive electrode of the battery cell. When designing a cylindrical battery cell, on the one hand, the top cover structure needs to play a role in sealing the battery cell, and on the other hand, it also needs to be connected to the electrode core. Therefore, for the top cover structure, in addition to designing necessary openings (such as liquid injection holes), the top cover structure adopts an integral structure. To ensure the performance and safety of the battery cell, when specifically designing the top cover structure, the entire top cover structure is not designed as the positive electrode, but a part of the top cover structure forms the positive electrode terminal. Therefore, certain parts in the top cover structure need to be isolated by parts with insulating properties, and then the isolated part is used as the positive electrode terminal and connected to the electrode core, so that this isolated part of the top cover structure forms the positive electrode.

[0057] For the top cover structure of the above-mentioned structural form, the selection of the insulating part and the connection design between the insulating part and the top cover structure play a decisive role in the sealing performance. Using the above method is likely to cause poor sealing, resulting in liquid leakage, and at the same time, the quality requirements for the insulating part are relatively high. In addition, since the electrode core needs to be connected to the isolated part of the top cover structure, the connection method is limited and the connection reliability is low.

[0058] Therefore, for the existing top cover structure, there are unreasonable structural designs, resulting in poor comprehensive performance of the battery cell.

[0059] Based on the above current situation and problems, the embodiments of the present application provide a battery cell. The top cover structure in this battery cell adopts a layered structure, and different layers perform different functions. For example, the first layer can be designed to seal the battery cell, and the second layer can be designed to form a terminal (which can be a positive terminal). This terminal needs to pass from the inside to the outside or from the inside to the outside through the first layer for sealing the battery cell, and then a third layer with sealing and insulating properties is arranged between the first layer and the second layer to achieve sealing and insulation between the first layer and the second layer.

[0060] In the above design concept, the top cover structure adopts a layered structure design, and the execution of each function does not interfere with each other. The structural design is simple and the performance is stable, which is beneficial to improving the comprehensive performance of the battery cell.

[0061] It should be noted that in the embodiments of the present application, the stacking order of different functional layers in the layered structure is not limited. For example, the aforementioned second layer can be disposed on the upper side of the first layer, or the second layer can be disposed on the lower side of the first layer. In the following embodiments, the above two cases will be introduced respectively. For the convenience of understanding, the embodiments in which the second layer is disposed on the upper side of the first layer are collectively referred to as the first type of embodiments, and the embodiments in which the second layer is disposed on the lower side of the first layer are collectively referred to as the second type of embodiments. It can be understood that in the above two types of embodiments, in order to achieve the sealing and insulation between the first layer and the second layer, the third layer needs to be designed between the first layer and the second layer, or at least a part of the third layer is disposed between the first layer and the second layer.

[0062] It can be recognized that in the following descriptions of the first type of embodiments and the second type of embodiments, there will be differences in the structures caused by the different stacking orders of different functional layers. These differences are mainly reflected in the formation method of the terminal post and the connection method between the terminal post and the electrode core. It should be understood that in the two types of embodiments described below, many structural designs can be borrowed from each other. For example, the design of the boss in the following embodiments.

[0063] It should be recognized that the performance of the battery cell in the embodiments of the present application is mainly optimized based on the design of the top cover structure. The top cover structure includes multiple different functional layers, such as the aforementioned first layer, second layer, and third layer. The structural bodies such as the terminal post are formed by a certain functional layer. For example, the terminal post is formed by the second layer, and the sealing and insulation performance needs to be achieved by the third layer disposed between the first layer and the second layer. To ensure the stability of the layered structure of the top cover structure, on the one hand, the shapes and sizes of the structural bodies including the terminal post need to be designed according to the size of the battery cell and the sizes of different functional layers, so that the structural bodies including the terminal post can occupy a reasonable ratio in terms of size. For example, the size of the terminal post and the size of the second layer have a reasonable ratio; on the other hand, the third layer disposed between the first layer and the second layer also needs to have a reasonable structure, or the third layer and the first layer, the second layer have a suitable overlapping length. These detailed designs are described in detail in the following embodiments.

[0064] Figure 1 Fig. shows a schematic structural diagram of a battery cell provided according to an embodiment of the present application; Figure 2 Fig. shows an exploded view of a battery cell provided according to an embodiment of the present application; Figure 3 Fig. shows a cross-sectional view of a battery cell provided according to an embodiment of the present application. In the embodiments of the present application, the battery cell includes a housing 100, an electrode core 200 (which can be referred to in combination with Figure 7 ). And a top cover structure 300.

[0065] The outer shell 100 serves as a protective shell for the battery cell. To ensure its strength and structural stability, the outer shell 100 can be made of materials such as aluminum or aluminum alloy. The outer shell 100 can be manufactured by stamping or integrally injection molding. The outer shell 100 has a receiving cavity 101 and an opening communicating with the receiving cavity 101. The outer shell 100 can be configured as a cylinder. Specifically, it can be a cylindrical structure with one end open. In other embodiments, the outer shell 100 can also be configured as other structures.

[0066] The electrode core 200 is disposed in the receiving cavity 101. The electrode core 200 can adopt different structural forms. For example, when adapted to the above-mentioned cylindrical outer shell 100, the electrode core 200 can adopt a wound core structure. The wound core structure can be formed by winding a positive electrode sheet, a separator, and a negative electrode sheet and is in a cylindrical shape. Of course, the electrode core 200 can also adopt other structures.

[0067] To achieve electrical connection between the electrode core 200 and the top cover structure 300, the electrode core 200 is further provided with a positive electrode tab 210 and a negative electrode tab. The positive electrode tab 210 and the negative electrode tab can be disposed at both ends of the electrode core 200. The positive electrode tab 210 is connected to the positive electrode sheet, and the negative electrode tab is connected to the negative electrode sheet. Combining the foregoing, the positive electrode tab 210 can also be connected to the top cover structure 300, and the negative electrode tab can be connected to the bottom of the outer shell 100. Of course, in some cases, the positive electrode tab 210 can be connected to the bottom of the outer shell 100, and the negative electrode tab can be connected to the top cover structure 300.

[0068] The top cover structure 300 adopts the above-mentioned layered structure. The top cover structure 300 can seal the opening of the outer shell 100. A boss 331 is formed by the protrusion of a certain functional layer in the top cover structure 300. The boss 331 can serve as the aforementioned pole column. The boss 331 can be connected to the electrode core 200. Specifically, it can be connected to the positive electrode tab 210 of the electrode core 200 or the negative electrode tab of the electrode core 200. For the convenience of description, in the following embodiments, the case where the boss 331 is connected to the positive electrode tab 210 is taken as an example for illustration.

[0069] In the above-mentioned battery cell, due to the layered structure design of the top cover structure 300, the structure design of the battery cell is simple and the performance is stable, which is beneficial to improving the comprehensive performance of the battery cell. In addition, the pole column is designed as the boss 331, and the third layer can be designed in a structure form that wraps the boss 331, so the sealing performance is better, and the boss 331 can also form a better connection with the positive electrode tab 210.

[0070] In some embodiments, please refer to Figure 3 ., the boss 331 is formed with a flat connection surface, and the electrode core 200 has a planar tab. A surface contact is formed between the boss 331 and the tab.

[0071] The boss 331 is in surface contact with the tab, which can improve the connection reliability between the boss 331 and the tab, and is beneficial to improving the comprehensive performance of the battery cell.

[0072] In the above embodiment, the connecting surface may be continuous or discontinuous. For the former, the boss 331 can be formed by a single bending process. For the latter, the boss 331 can be designed into a continuously bent zigzag structure through multiple bending processes.

[0073] It can be understood that in actual design, the size of the boss 331 can be determined according to specific requirements. For example, when a larger current-carrying area is required to avoid excessive heat generation at the boss 331, the boss 331 can be designed larger so that it can be connected to the tab with a larger contact area. Another example is that when the overall size of the battery cell is small, the boss 331 can be designed smaller according to the ratio with the overall size of the battery cell.

[0074] In some embodiments, please refer to Figure 3 When the second layer for forming the boss 331 in the top cover structure 300 is located above the first layer, that is, corresponding to the foregoing first type of embodiment, in order to achieve sealing and insulation between the first layer and the second layer, an insulating member 400 also needs to be designed between the tab and the first layer. The insulating member 400 can be an insulating film, insulating adhesive tape, etc.

[0075] In some embodiments, please refer to Figure 3 The battery cell is further provided with a liquid injection structure 500, which can be formed in the top cover structure 300 and is used for injecting liquid into the battery cell.

[0076] The formation method of the liquid injection structure 500 and its surrounding structure can refer to the relevant embodiments of the following top cover structure 300. In this battery cell structure, the liquid injection structure 500 can be located at the center of the battery cell (as shown in Figure 3 ), or can be located at the edge of the battery cell (as shown in Figure 6 ). The size of the liquid injection structure 500 can be considered according to factors such as the overall size of the battery cell, and the distance between the liquid injection structure 500 and the boss 331 can also be designed according to actual requirements.

[0077] In the first type of embodiment of the present application, please refer to Figure 1 and Figure 3 , the top cover structure 300 includes a sealing cover 310, a sealing and insulating layer 320, and a conductive sheet 330.

[0078] Combined with the foregoing, the sealing cover 310 is the foregoing first layer, the conductive sheet 330 can be the foregoing second layer, and the sealing and insulating layer 320 can be the foregoing third layer.

[0079] The sealing cover 310 can be hermetically connected to the outer shell 100 of the battery cell, and the connection method is not limited. For example, the connection between the sealing cover 310 and the outer shell 100 can be achieved by laser welding. To improve the connection reliability, structures that can fit with each other can be provided at the edge of the sealing cover 310 and the inner side of the top of the outer shell 100. For example, a first step is designed at the edge of the sealing cover 310, and a second step is designed on the outer shell 100. During assembly, a fit can be formed between the first step and the second step to achieve pre-positioning between the sealing cover 310 and the outer shell 100, and then the fixed connection between the two can be achieved by laser welding.

[0080] A first through hole 311 is formed in the sealing cover 310, and a second through hole 312 can also be provided. The first through hole 311 is used to receive the boss 331 in the top cover structure 300, and the second through hole 312 can be used as the liquid injection hole of the battery cell, which can form a liquid injection channel, thereby forming the aforementioned liquid injection structure 500.

[0081] The sealing and insulating layer 320 is provided on the side of the sealing cover 310 facing away from the electrode core 200 and is formed with a third through hole 321 communicating with the first through hole 311. After the third through hole 321 communicates with the first through hole 311, a channel for the boss 331 to extend into or pass through can be formed.

[0082] The conductive sheet 330 is provided on the side of the sealing and insulating layer 320 facing away from the electrode core 200. The conductive sheet 330 is formed with the aforementioned boss 331, and the boss 331 can pass through the third through hole 321 and the first through hole 311 and be connected to the electrode core 200.

[0083] In the above-mentioned top cover structure 300, the sealing cover 310 can be connected to the outer shell 100 to play a role in sealing the battery cell. The boss 331 on the conductive sheet 330 can pass through the first through hole 311 and the third through hole 321 and be connected to the electrode core 200. The boss 331 in the conductive sheet 330 plays a role in forming a pole column. The second through hole 312 can be used as the liquid injection hole of the battery cell, and the sealing and insulating layer 320 is used to seal and insulate the sealing cover 310 and the conductive sheet 330. The three-layer structure cooperates with each other, and the execution of each function does not interfere with each other. The structure design is simple and the performance is stable, which is beneficial to improving the comprehensive performance of the battery cell. In addition, by using the boss 331 to form the pole column, the sealing and insulating layer 320 can be well wrapped around the boss 331, which can simplify the setting method of the sealing and insulating layer 320 on the basis of forming a good seal. The boss 331 can also form a better connection with the electrode core 200, which can also improve the comprehensive performance of the battery cell.

[0084] The battery cell in the embodiment of the present application is designed based on the layered structure of the top cover structure 300, which makes the structure design of the battery cell simple and the performance stable, and is beneficial to improving the comprehensive performance of the battery cell.

[0085] In the above-mentioned top cover structure 300, the aperture diameters of the first through hole 311 on the enclosure cover 310 and the third through hole 321 on the sealing and insulating layer 320 are both larger than the outer diameter of the boss 331, so that the boss 331 can protrude from the third through hole 321 and the first through hole 311. For the first through hole 311, the size of the first through hole 311 can be designed according to the outer diameter of the boss 331 and the overall size of the enclosure cover 310, and the size of the third through hole 321 can be designed according to the outer diameter of the boss 331 and the whole of the sealing and insulating layer 320.

[0086] In some embodiments, the aperture diameters of the first through hole 311 and the third through hole 321 are the same, so that the first through hole 311 and the third through hole 321 are flush. This setting with the same aperture diameter can be used as a positioning reference to enable the enclosure cover 310 and the sealing and insulating layer 320 to achieve more precise assembly based on this positioning reference.

[0087] In some embodiments, please refer to Figure 3 , the periphery of the third through hole 321 extends into the first through hole 311, and the inner diameter of the third through hole 321 is smaller than the inner diameter of the first through hole 311.

[0088] In the above-mentioned embodiments, the sealing and insulating layer 320 is closer to the boss 331 than the enclosure cover 310, and can play a better role in sealing and insulation.

[0089] In some specific embodiments, the length L1 of the periphery of the third through hole 321 extending into the first through hole 311 satisfies the relationship:

[0090] L1≥0.1mm.

[0091] With this design, the diameter of the first through hole 311 is the largest, the outer diameter of the boss 331 is the second, and the aperture diameter of the third through hole 321 is the smallest. Taking the above value for L1 can improve the sealing and insulation while ensuring the structural stability.

[0092] It can be understood that the value of L1 should not be too large, and its specific value can be set according to specific requirements.

[0093] In the above specific embodiments, please refer to Figure 3, a gap S is formed between the boss 331 and the housing cover 310. To improve the sealing performance and insulation performance, a material with insulation and sealing properties can also be filled in the gap S. This part of the material can be the same as or different from the material used for the sealing and insulating layer 320. It can be understood that, as the side closer to the electrode core 200, the material filled in the gap S can have better heat resistance. Thus, for the boss 331, the sealing and insulating layer 320 and the gap S can form a two-layer structure between the housing cover 310 and the conductive sheet 330, improving the sealing and insulation performance.

[0094] In some embodiments, please refer to Figure 3 , the boss 331 extends out of the first through hole 311. It can be understood that the conductive sheet 330 is located on the upper side of the sealing and insulating layer 320, and a part of the conductive sheet 330 forms the boss 331. The boss 331 can pass through the third through hole 321 and the first through hole 311, so that the connection surface of the boss 331 can extend beyond the housing cover 310.

[0095] It can be understood that designing the boss 331 to extend beyond the housing cover 310 can effectively reduce the structure of the tab. Specifically, the tab in the electrode core 200 needs to be led out from one side or one end of the battery cell. To realize the connection between the tab and the boss 331 and ensure the insulation between the tab and the housing cover 310, a better way is that the tab cannot touch the housing cover 310 after being connected to the boss 331. It can be understood that adopting the design of the boss 331 extending beyond the housing cover 310 can avoid the contact between the tab and the housing cover 310. For the tab, there is no need to design a related avoidance structure, making the structure of the tab simple. For example, as described above, in Figure 3 the shown example, the connection surface of the boss 331 is a continuous plane, and the side of the housing cover 310 facing the electrode core 200 is also designed as a plane. When the boss 331 extends beyond the housing cover 310, it means that the two planes never intersect in the horizontal direction. When the tab, which is also planar, is connected to the boss 331 in a surface-contact manner, the tab naturally avoids the housing cover 310.

[0096] In the above embodiments, the length of the boss 331 extending out of the first through hole 311 can be designed so that the tab can fully avoid the housing cover 310 without affecting the overall size of the battery cell.

[0097] In some specific embodiments, the length L2 of the boss 331 extending out of the first through hole 311 satisfies the relationship:

[0098] L2 = 0.05 mm to 0.2 mm.

[0099] It can be understood that by adopting the above values for L2, the tab can be fully avoided from the cover 310 of the encapsulation while the size of the battery cell can be compressed as much as possible, and it can be avoided that the boss 331 occupies more internal space of the battery cell due to exceeding the cover 310, which affects the energy density of the battery cell.

[0100] Combined with the foregoing content, it can be known that in the embodiment of the present application, the cover 310 of the encapsulation can be directly connected to the outer shell 100 of the battery cell and seal the opening of the outer shell 100. It is mainly used to form the packaging structure of the battery cell together with the outer shell 100. Therefore, the cover 310 of the encapsulation can be made of a metal material. The cover 310 of the encapsulation can be designed to be non-conductive to current, while the conductive sheet 330 can be set to be conductive to current. Each performs its own functions, and then through the setting of the sealing and insulating layer 320, the insulation and sealing between the cover 310 of the encapsulation and the conductive sheet 330 are realized. For the conductive sheet 330, its main purpose is to form the boss 331. In order to enable the boss 331 to be connected to the electrode core 200 located inside the outer shell 100, the boss 331 needs to pass through the cover 310 of the encapsulation and the sealing and insulating layer 320. At this time, for the surrounding structure of the boss 331, the cover 310 of the encapsulation, the sealing and insulating layer 320 and the boss 331 need to be set with a tight assembly relationship, and at the same time, it is necessary to ensure that the top cover structure 300 has sufficient structural strength around the boss 331.

[0101] Based on the above considerations, the embodiment of the present application designs the overlapping manner of the cover 310 of the encapsulation, the sealing and insulating layer 320 and the conductive sheet 330. For example, please refer to Figure 3 , in some embodiments, a overlapping section W is formed around the cover 310 of the encapsulation, the sealing and insulating layer 320 and the conductive sheet 330 adjacent to the first through hole 311. The length L3 of the overlapping section W satisfies the relationship:

[0102] L3>0.5mm.

[0103] It can be understood that in the Figure 3 illustrated example, from the diameter direction of the battery cell, two overlapping sections W are formed around the boss 331. To ensure the balanced connection strength, sealing performance and insulating performance, the lengths of the two overlapping sections W both need to meet the above numerical range.

[0104] In the embodiments of the present application, it can be understood that since both the sealed insulating tube layer 320 and the conductive sheet 330 are provided on the upper side of the housing cover 310, for the internal space of the battery cell, it mainly depends on the sizes of the outer shell 100 and the housing cover 310, and is also affected by the size of the boss 331. This influence mainly comes from the design method where the boss 331 exceeds the housing cover 310. In addition, the size design of the boss 331 is related to the overall size design of the battery cell, the size design of the conductive sheet 330, and the size design of the housing cover 310. Therefore, when designing the top cover structure 300, various size indicators need to be comprehensively considered.

[0105] In the above embodiments, some important dimensions were sorted out and described mainly from the common aspects of the top cover structure 300, such as L1, L2, and L3 in the foregoing embodiments. In other words, the size designs of L1, L2, and L3 can be applied to most top cover structures 300. In addition to these size designs, it should be recognized that other size designs in the top cover structure 300 also affect the performance of the battery cell.

[0106] In some embodiments, the diameter of the boss 331 is 1 mm to 5 mm, and the height of the boss 331 is 0.1 mm to 0.5 mm.

[0107] Designing the boss 331 with the above dimensions is easy to form, and at the same time can ensure its conduction function. For example, when the diameter of the boss 331 is designed to be 1 mm and its height is designed to be 0.1 mm, the boss 331 with this proportional relationship is more stable in structure; when the diameter of the boss 331 is designed to be 2.5 mm and its height is designed to be 0.25 mm, this proportional relationship is more balanced in performance; when the diameter of the boss 331 is designed to be 5 mm and its height is designed to be 0.5 mm, the boss 331 with this proportional relationship can provide a larger current-carrying area, making it applicable to large-capacity battery cells.

[0108] In some embodiments, the thickness of the housing cover 310 is 0.1 mm to 0.5 mm. The housing cover 310 includes a stainless steel layer and a nickel plating layer, and the thickness of the nickel plating layer is 0.5 μm to 3 μm.

[0109] Designing the housing cover 310 with the above dimensions has a relatively high structural strength, and at the same time, based on the design of the nickel plating layer, the housing cover 310 can have a relatively high hardness. It can be understood that the thickness of the nickel plating layer should be designed according to the overall thickness of the housing cover 310, and the overall thickness of the housing cover 310 can be designed according to the capacity required by the battery cell.

[0110] In some embodiments, the thickness of the conductive sheet 330 is 0.1 mm to 0.5 mm. The thickness of the conductive sheet 330 can be designed with reference to the enclosure cover 310. On the basis of ensuring that the conductive sheet 330 has sufficient structural strength, the thickness of the conductive sheet 330 can be made the same as that of the enclosure cover 310, thereby improving the overall strength of the top cover structure 300.

[0111] In some embodiments, the sealing and insulating layer 320 includes a sealing adhesive film, and the sealing adhesive film is connected between the enclosure cover 310 and the conductive sheet 330 by hot pressing. The thickness of the sealing adhesive film before hot pressing is H and H = 0.08 mm to 0.2 mm, and the thickness of the sealing adhesive film after hot pressing is h and h = (20% to 80%) * H.

[0112] The thickness of the above-mentioned sealing adhesive film can be comprehensively considered in combination with the thickness of the conductive sheet 330 and the enclosure cover 310. After hot pressing the sealing adhesive film, it can be tightly connected between the enclosure cover 310 and the conductive sheet 330.

[0113] When performing hot pressing, it can be concentrated on the central area of the above-mentioned overlapping section w, so that the sealing adhesive film can uniformly diffuse from the central area to both sides on the overlapping section w, so as to improve the connection reliability between the enclosure cover 310 and the conductive sheet 330. It can be understood that by using the above hot pressing method, the overflow glue part of the sealing adhesive film will be concentrated at both ends of the overlapping section, for example, concentrated at the connection between the sealing adhesive film and the boss 331. This overflow glue method will form a thicker overflow glue layer at the connection, which is beneficial to improving the sealing performance and insulation performance.

[0114] For example, please refer to Figure 3 , the sealing and insulating layer 320 forms overflow glue parts 323 at both ends of the overlapping section W, an insulating layer 324 is formed between the overflow glue parts 323, and the thickness of the overflow glue part 323 is greater than the thickness of the insulating layer 324. The overflow glue part 323 can form a thicker overflow glue layer, thereby improving the sealing performance and insulation performance.

[0115] Figure 4 Shows a cross-sectional view of another battery cell provided according to an embodiment of the present application; Figure 5 Shows a cross-sectional view of yet another battery cell provided according to an embodiment of the present application.

[0116] In some embodiments, please refer to Figure 4 , the conductive sheet 330 can form a boss 331 through a stamping process, and the boss 331 is a hollow structure.

[0117] The stamping process has simple forming and low process cost. The hollow-structured boss 331 can save the material of the conductive sheet 330 and reduce the material cost.

[0118] In some embodiments, please refer to Figure 5, the conductive sheet 330 can form a boss 331 through an extrusion process, and the boss 331 is a solid structure.

[0119] Specifically, the boss 331 with a solid structure has higher strength, which can improve the connection reliability between the boss 331 and the tab.

[0120] The above content fully describes the main structural components of the top cover structure 300. In addition to the above, for the battery cell, it also needs to be configured with a second through hole 312, which can also be integrally designed into the top cover structure 300. It can be understood that the size and position of the second through hole 312 can be set according to requirements.

[0121] For example, in some embodiments, please refer to Figure 1 and Figure 3 , the top cover structure 300 adopts a central liquid injection method. A second through hole 312 is also provided on the sealing cover 310. The second through hole 312 is located at the center of the sealing cover 310, and the first through hole 311 is located on one side of the second through hole 312. The sealing insulating layer 320 has a fourth through hole 322 communicating with the second through hole 312, and the conductive sheet 330 has a fifth through hole 332 communicating with the second through hole 312.

[0122] The second through hole 312, the fourth through hole 322, and the fifth through hole 332 communicate to form a liquid injection structure 500 with a liquid injection channel, and the electrolyte can enter the battery cell through a liquid injection device and through this liquid injection channel.

[0123] It can be understood that the apertures of the second through hole 312, the fourth through hole 322, and the fifth through hole 332 are not limited, and the three can have the same aperture or different apertures.

[0124] In some specific embodiments, the second through hole 312 can be designed as a stepped hole, which is convenient for correspondingly designing the second through hole cover 340 in the following embodiments. The plane of the second through hole cover 340 does not exceed the top surface of the conductive sheet 330, so that the second through hole cover 340 can be hidden and installed into the second through hole 312.

[0125] In some specific embodiments, please refer to Figure 3 , the second through hole 312 is provided in a protruding manner. For example, a protruding portion 313 can be formed on the sealing cover 310, and then the second through hole 312 is provided on the protruding portion 313. The protruding portion 313 forms a liquid injection platform, which is convenient for the liquid injection device to be connected to this liquid injection platform. The height of this liquid injection platform is not limited, and it can be designed to be slightly higher than the conductive sheet 330 or slightly lower than the conductive sheet 330.

[0126] In some specific embodiments, please refer to Figure 4 andFigure 5 The second through-hole 312 is directly formed on the encapsulation cover 310. The second through-hole 312 can be hidden by the sealing insulation layer 320 and the conductive sheet 330, providing protection for the second through-hole 312.

[0127] In some specific embodiments, the encapsulation cover 310 is made of a first material that at least includes stainless steel. The top cover structure 300 further includes a second through-hole cover 340 for closing the second through-hole 312.

[0128] Here, the material of the encapsulation cover 310 is designed to be made of a first material that at least includes stainless steel. The second through-hole cover 340 can be connected to the encapsulation cover 310 by laser welding, thereby improving the connection strength.

[0129] In addition, the second through-hole cover 340 on the second through-hole 312 is made of a second material that at least includes stainless steel. When laser welding is used, based on the characteristics of the stainless steel material, the phenomenon of welding explosion points during the welding process can be avoided, further enhancing the connection strength between the second through-hole cover 340 and the encapsulation cover 310.

[0130] For another example, in some other embodiments, reference can be made to Figure 6 and Figure 7 The top cover structure 300 adopts an eccentric liquid injection method. The encapsulation cover 310 is further provided with a second through-hole 312. The first through-hole 311 is located at the center of the encapsulation cover 310, and the second through-hole 312 is located on one side of the first through-hole 311.

[0131] For the aperture setting, height setting, etc. of the second through-hole 312 in these other embodiments, reference can be made to the foregoing content and will not be elaborated here.

[0132] It can be understood that based on the layered design of the top cover structure 300, the purpose of conveniently adjusting the liquid injection method can be achieved. When designing the top cover structure 300, only the position of the second through-hole 312 needs to be reasonably arranged. The position selection of the second through-hole 312 is diverse and the structure is simple.

[0133] In some embodiments, the sealing insulation layer 320 and the conductive sheet 330 extend from one side of the second through-hole 312 to the other side of the second through-hole 312 and extend to a predetermined length.

[0134] Combined with the foregoing dimension design of the overlapping section, it can be known that for the top cover structure 300 in the embodiment of the present application, the parts that need to be sealed are mainly concentrated in the second through hole 312 and the first through hole 311. For the second through hole 312, based on the foregoing material selection of the enclosure cover 310, the second through hole cover 340 can be directly connected to the enclosure cover 310. Therefore, excellent sealing of the second through hole 312 can be achieved, and the sealing can be achieved without involving the sealing insulating layer 320 and the conductive sheet 330. The sealing can be achieved by connecting the second through hole cover 340 to the enclosure cover 310. For the first through hole 311, the sealing needs to be achieved by means of the stacking relationship of the enclosure cover 310, the sealing insulating layer 320 and the conductive sheet 330. To achieve this sealing, the conductive sheet 330 and the sealing insulating layer 320 need to be reasonably arranged around the first through hole 311.

[0135] Based on the above considerations, reference can be made in combination with Figures 3 to 5 , the sealing insulating layer 320 and the conductive sheet 330 located on the left side of the second through hole 312 can be completely removed without affecting the overall performance of the battery cell. Here, reference can be made to Figure 8 , it can be understood that the part with a notch (such as the first notch 333 and the second notch 325 in the following embodiments) can correspond to the position of the second through hole 312, which can save the materials of the sealing insulating layer 320 and the conductive sheet 330 respectively.

[0136] Figure 6 Fig. shows an exploded schematic view of another battery cell provided according to an embodiment of the present application; Figure 7 Fig. shows a cross-sectional view of another battery cell provided according to an embodiment of the present application.

[0137] In the second type of embodiments of the present application, please refer to Figure 6 and Figure 7 , the top cover structure 300 includes an enclosure cover 310, a sealing insulating layer 320 and a conductive sheet 330.

[0138] This enclosure cover 310 serves as the aforementioned first layer, this conductive sheet 330 serves as the aforementioned second layer, and this sealing insulating layer 320 serves as the aforementioned third layer.

[0139] This enclosure cover 310 can be sealingly connected to the outer shell 100 of the battery cell, and the connection method is not limited. For example, the connection between the enclosure cover 310 and the outer shell 100 can be achieved by laser welding. To improve the connection reliability, an interlocking structure form can be adopted, and this interlocking structure can refer to the aforementioned first type of embodiments.

[0140] A first through-hole 311 and a second through-hole 312 are formed on the casing cover 310. A second through-hole cover 340 may be provided on the second through-hole 312. The first through-hole 311 is used to receive the boss 331 in the top cover structure 300, and the second through-hole 312 may serve as a liquid injection hole.

[0141] The sealing and insulating layer 320 is disposed on the side of the casing cover 310 facing the electrode core 200 and is formed with a third through-hole 321 communicating with the first through-hole 311. After the third through-hole 321 communicates with the first through-hole 311, a channel for the above-mentioned boss 331 to extend into or pass through can be formed.

[0142] The conductive sheet 330 is disposed under the sealing and insulating layer 320. The conductive sheet 330 is formed with the above-mentioned boss 331, and the boss 331 can pass through the third through-hole 321 and be connected to the electrode core 200.

[0143] In the above-mentioned top cover structure 300, the casing cover 310 functions to seal the battery cell. The boss 331 in the conductive sheet 330 functions to form a terminal post. The sealing and insulating layer 320 is used to seal and insulate the casing cover 310 and the conductive sheet 330. The three-layer structure cooperates with each other, and the execution of each function does not interfere with each other. The structural design is simple and the performance is stable, which is beneficial to improving the comprehensive performance of the battery cell. In addition, by adopting the method of forming the terminal post with the boss 331, the sealing and insulating layer 320 can be well wrapped around the boss 331, which can simplify the setting method of the sealing and insulating layer 320 on the basis of forming a good seal. The boss 331 can also form a better connection with the electrode core 200, which can also improve the comprehensive performance of the battery cell.

[0144] Different from the foregoing first type of embodiments, in this second type of embodiments, both the sealing and insulating layer 320 and the conductive sheet 330 are located under the casing cover 310. For the boss 331 formed on the conductive sheet 330, the boss 331 can be connected to the tab in the electrode core 200. The protruding direction of the boss 331 is different from that of the foregoing first type of embodiments. In this second type of embodiments, the protruding direction of the boss 331 is from bottom to top, and its purpose is to form the positive electrode of the battery cell so as to form an electrical connection with an external electronic device.

[0145] In addition, please refer to Figure 7 , since the conductive sheet 330 is disposed under the casing cover 310 and the sealing and insulating layer 320 is between the conductive sheet 330 and the casing cover 310, insulation and sealing have been formed therebetween. When connecting the tab to the boss 331, the tab is naturally isolated from the casing cover 310, and it can naturally avoid forming a current path between the casing cover 310 and the tab.

[0146] In addition to the above, in this second type of embodiment, regarding the size design of each structure and the design of the positional relationship between each structure, for example, the size design of the boss 331, the aperture settings of the first through-hole 311 and the third through-hole 321, and the design of their positional relationship, reference may be made to the aforementioned first type of embodiment, and details will not be elaborated herein.

[0147] It should be noted that in this second type of embodiment, for the peripheral structure of the boss 331, a tight fitting relationship needs to be set among the sealing cover 310, the sealing insulating layer 320, and the boss 331. At the same time, it is also necessary to ensure that the top cover structure 300 has sufficient structural strength around the boss 331. In this regard, the length of the overlapping section W can be reasonably configured with reference to the first type of embodiment.

[0148] In this second type of embodiment, the liquid injection form can also be appropriately changed. For example, a second through-hole 312 is further provided on the sealing cover 310. The second through-hole 312 can be located at the center position of the sealing cover 310, and the first through-hole 311 is located on one side of the second through-hole 312, or the first through-hole 311 is located at the center position of the sealing cover 310, and the second through-hole 312 is located on one side of the first through-hole 311. The sealing insulating layer 320 has a fourth through-hole 322 communicating with the second through-hole 312, and the conductive sheet 330 has a fifth through-hole 332 communicating with the second through-hole 312. The detailed design method can be referred to the aforementioned first type of embodiment.

[0149] In some embodiments, please refer to Figure 7 When the first through-hole 311 is located at the center position of the sealing cover 310 and the second through-hole 312 is located on one side of the first through-hole 311, the distance L4 between the center of the second through-hole 312 and the edge of the sealing cover 310 adjacent to the second through-hole 312 satisfies the relationship:

[0150] L4 > 0.6 mm.

[0151] Setting L4 according to the above dimensions can ensure that the edge of the second through-hole 312 has sufficient structural strength, enabling the sealing cover 310 to be stably connected to the outer shell 100. At the same time, it can avoid interference of the side wall on liquid injection, that is, prevent the electrolyte from being easily retained between the sealing cover and the outer shell during the liquid injection process, resulting in electrolyte loss and affecting the wetting effect of the winding core. This size design can be applied to the aforementioned first type of embodiment.

[0152] In some embodiments, the diameter of the second through-hole 312 is D1, and the diameter of the second through-hole cover 340 is D2. D1 and D2 satisfy the relationship:

[0153] D2 - D1 > 0.5 mm.

[0154] The size of the second through-hole cover 340 is designed to be larger than that of the second through-hole 312, which can make the second through-hole cover 340 completely seal the second through-hole 312, improving the sealing effect of the second through-hole cover 340 on the second through-hole 312. In addition, the second through-hole cover 340 has a greater buffer margin when covering the second through-hole 312, which helps to maintain a stable sealing state even when the battery cell vibrates or the temperature changes significantly, extending the service life of the battery cell. This size design can be applied to the aforementioned first type of embodiments.

[0155] In some embodiments, the thickness of the second through-hole cover 340 is H1, and the thickness of the case cover 310 is H2, and H1 and H2 satisfy the relationship:

[0156] H1 < 0.75H2.

[0157] Here, the thickness of the second through-hole cover 340 and the thickness of the case cover 310 are designed so that the thickness of the second through-hole cover 340 is less than that of the case cover 310, which can avoid local extrusion of the case cover 310 due to the large weight at the position of the second through-hole cover 340, balance the strength relationship between the case cover 310 and the second through-hole cover 340, and improve the overall strength of the top cover structure 300. On the other hand, designing the thickness of the second through-hole cover 340 to be smaller means smaller welding parameters, welding power, and welding time, which can provide faster heat transfer, help to form weld marks faster and ensure the weld quality. At the same time, it can prevent excessive thermal deformation of the second through-hole cover 340 and reduce unnecessary distortion or deformation. This size design can be applied to the aforementioned first type of embodiments.

[0158] It should be noted that in this second type of embodiment, the notch design method can also be adopted, that is, the sealing insulating layer 320 and the conductive sheet 330 are designed to have a notched shape.

[0159] In some embodiments, please refer to Figure 7 , the projection of the positive electrode tab 210 in the thickness direction of the battery cell does not overlap with the projection of the second through-hole cover 340 in the thickness direction of the battery cell, which can prevent the positive electrode tab 210 from interfering with the liquid injection during the liquid injection process and affecting the infiltration of the electrolyte into the battery cell.

[0160] Figure 8 shows an exploded view of another battery cell provided according to the embodiments of the present application; Figure 9 shows a cross-sectional view of another battery cell provided according to the embodiments of the present application.

[0161] Please refer to Figure 8 and Figure 9, the sizes of the conductive sheet 330 and the sealing insulating layer 320 are smaller than the size of the enclosure cover 310. The conductive sheet 330 and the sealing insulating layer 320 are each formed with a notch. For this second type of embodiment, the existence of the notch can reduce the space occupied by the conductive sheet 330 and the sealing insulating layer 320 within the battery cell, which is beneficial to improving the energy density of the battery cell.

[0162] Specifically, the conductive sheet 330 includes a first notch 333, the sealing insulating layer 320 is provided with a second notch 325 corresponding to the first notch 333, and the projection of the second through-hole cover 340 in the thickness direction of the battery cell does not overlap with the projection of the conductive sheet 330 or the sealing insulating layer 320 in the thickness direction of the battery cell.

[0163] Through the design of the above-mentioned first notch 333 and second notch 325, the material usage of the sealing insulating layer 320 and the conductive sheet 330 can be reduced, and the space occupied by the conductive sheet 330 and the sealing insulating layer 320 within the battery cell can be reduced, which is beneficial to improving the energy density of the battery cell.

[0164] In this second type of embodiment, the enclosure cover 310 may also include a convex portion extending in a direction away from the electrode core 200, and the second through-hole 312 may be formed on the convex portion.

[0165] In some embodiments, the end of the sealing insulating layer 320 close to the outer shell 100 extends beyond the end of the conductive sheet 320 close to the outer shell 100. With this design, it is possible to prevent a short-circuit phenomenon caused by the conductive sheet 330 shaking up and down and contacting the enclosure cover 310 during the transportation of the battery cell.

[0166] In some embodiments, please refer to Figure 9 , the electrode core 200 has a central through-hole 201, an electrode core insulating layer 600 is provided on the upper side of the electrode core 200, the electrode core insulating layer 600 is provided with an insulating through-hole 601, and the diameter of the insulating through-hole 601 is smaller than the diameter of the central through-hole 201.

[0167] The setting of the electrode core insulating layer 600 can further improve the insulation performance and prevent a short-circuit phenomenon caused by the positive electrode tab 210 partially falling off and connecting to the electrode core 200.

[0168] In the embodiments of the present application, various detailed designs of the top cover structure 300 (such as the above-mentioned size design and positional relationship design, the hollow design or solid design of the boss 331, the notch design or non-notch design, etc.) are not shown in the same drawing. It can be understood that these detailed designs can be combined as needed to form a variety of top cover structures 300 and battery cells that meet different requirements.

[0169] In an embodiment of the present application, an explosion-proof structure may also be provided on the top cover structure 300. For example, a pressure relief port may be opened at an appropriate position of the enclosure cover 310, and an explosion-proof valve is provided on one side of the pressure relief port. Under normal use conditions, the explosion-proof valve seals the pressure relief port. When the temperature inside the battery cell rises sharply and exceeds a predetermined value, the high-temperature gas can blow open the explosion-proof valve to achieve the purpose of pressure relief and prevent the battery cell from exploding.

[0170] The explosion-proof valve can be selected according to actual requirements. In some cases, the explosion-proof valve can also be replaced with an explosion-proof diaphragm.

[0171] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0172] In the description of the present invention, it should be understood that the terms "including" and "having" used in the present application and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products, or devices.

[0173] Unless otherwise clearly defined and limited, the terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be directly connected, or indirectly connected through an intermediate medium, and may be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features.

[0174] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A battery cell, characterized in that, Comprising: A housing having a receiving cavity and an opening communicating with the receiving cavity; An electrode core disposed in the receiving cavity; A top cover structure for sealing the opening, the top cover structure comprising: A sealing cover on which a first through hole and a second through hole are formed; A sealing insulating layer disposed on a side of the sealing cover facing away from the electrode core and having a third through hole communicating with the first through hole; And a conductive sheet disposed on a side of the sealing insulating layer facing away from the electrode core, the conductive sheet having a boss, the boss passing through the third through hole and the first through hole and connecting with the electrode core.

2. The battery cell according to claim 1, wherein, The second through hole is located at the center of the sealing cover, the first through hole is located on one side of the second through hole, or the first through hole is located at the center of the sealing cover, and the second through hole is located on one side of the first through hole.

3. The battery cell according to claim 1, wherein, The periphery of the third through hole extends into the first through hole, and the inner diameter of the third through hole is smaller than the inner diameter of the first through hole.

4. The battery cell according to claim 1, wherein, The boss extends out of the first through hole.

5. The battery cell according to claim 1, wherein, The sealing insulating layer has a fourth through hole communicating with the second through hole, the conductive sheet has a fifth through hole communicating with the second through hole, and the second through hole, the fourth through hole and the fifth through hole are in communication.

6. The battery cell according to any one of claims 1 to 5, characterized in that, The boss is a hollow structure or a solid structure.

7. The battery cell according to any one of claims 1 to 5, characterized in that, The boss forms a flat connecting surface, the electrode core has a planar tab, and a surface contact is formed between the boss and the tab.

8. The battery cell according to any one of claims 1 to 5, characterized in that, The sealing insulating layer and the conductive sheet extend from one side of the first through hole to the other side of the first through hole and extend to a predetermined length.

9. The battery cell according to claim 1, characterized in that, The conductive sheet includes a first notch, the sealing insulating layer is provided with a second notch corresponding to the first notch, a second through hole cover is provided on the second through hole, and a projection of the second through hole cover in the thickness direction of the battery cell does not overlap with a projection of the conductive sheet or the sealing insulating layer in the thickness direction of the battery cell.

10. The battery cell according to any one of claims 1 to 5, characterized in that, The electrode core includes a positive electrode sheet, a negative electrode sheet, and a separator disposed between the positive electrode sheet and the negative electrode sheet, the positive electrode sheet having a positive tab, and the negative electrode sheet having a negative tab; The positive tab is connected to the conductive sheet, and the negative tab is connected to the housing.

11. The battery cell according to claim 10, characterized in that, A projection of the positive tab in the thickness direction of the battery cell does not overlap with a projection of the second through hole cover in the thickness direction of the battery cell.

12. The battery cell according to any one of claims 1 to 5, characterized in that, The sealing cover includes a convex portion extending in a direction away from the electrode core, and the second through hole is formed on the convex portion.

13. The battery cell according to any one of claims 1 to 5, characterized in that, An end of the sealing insulating layer close to the housing extends beyond an end of the conductive sheet close to the housing.

14. The battery cell according to any one of claims 1 to 5, characterized in that, A first step is provided on a side of the sealing cover facing the housing, and a second step is provided on a side of the housing facing the sealing cover.

15. The battery cell according to any one of claims 1 to 5, characterized in that, The electrode core has a central through hole, an electrode core insulating layer is provided on an upper side of the electrode core, and an insulating through hole is provided in the electrode core insulating layer, and a diameter of the insulating through hole is smaller than a diameter of the central through hole.

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