Battery cap and single battery
By introducing an insulating layer-connected perforated plate and explosion-proof sheet into the battery cap, the problem of low space utilization caused by the gap between the perforated plate gaskets is solved, and the energy density is improved while ensuring safety.
Patent Information
- Application Number
- CN202423070390.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-11
- Publication Date
- 2025-12-12
- Estimated Expiration
- 2034-12-11
AI Technical Summary
In traditional cylindrical battery designs, the gap between the perforated plate gasket and the explosion-proof sheet results in low utilization of internal space, making it difficult to increase energy density while ensuring safety.
Design a battery cap including an explosion-proof sheet and a perforated plate. The perforated plate consists of a second substrate and a second conductive part connected by an insulating layer. The second conductive part is connected to the battery cell tab. The insulating layer is sandwiched between the perforated plate and the explosion-proof sheet, which simplifies the structure, increases the battery cell volume, and improves space utilization.
While keeping the external dimensions of the battery unchanged, the volume of the battery cell is increased, which improves the internal space utilization and energy density of the single battery cell, thereby enhancing the battery capacity and safety performance.
Smart Images
Figure CN223665549U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of battery technology, and in particular to a battery cap and a single battery cell. Background Technology
[0002] Cylindrical single-cell batteries, as a common battery form, are widely used in portable electronic devices, power tools, and electric vehicles. Due to their high energy density and good structural stability, they have become one of the most mainstream battery types. The basic structure of a cylindrical battery typically includes a battery casing, cell, cap, and explosion-proof diaphragm. The cap usually has a perforated plate for gas venting or electrode lead-out. An insulation gasket is typically used between the cap perforated plate and the explosion-proof diaphragm to prevent short circuits and other problems.
[0003] However, in traditional cylindrical battery designs, the fit between the perforated plate gasket and the explosion-proof sheet often results in a large gap between them, reducing the utilization rate of the battery's internal space. This problem is particularly prominent given the increasing miniaturization of batteries and the ever-increasing demands for energy density.
[0004] Therefore, how to improve the utilization rate of internal space and optimize the overall structural design of the battery while ensuring battery safety has become an important issue in the current development of battery technology. Utility Model Content
[0005] One objective of this invention is to provide a battery cap that addresses the technical problem of improving the utilization rate of internal space in a single battery cell.
[0006] To achieve the above objectives, in a first aspect, the present invention provides a solution: a battery cap, characterized in that it includes: an explosion-proof sheet, the explosion-proof sheet including a first substrate and a first conductive part connected to each other;
[0007] An orifice plate is disposed on one side of the explosion-proof sheet. The orifice plate includes an insulating layer, a second substrate and a second conductive part that are interconnected. The second conductive part and the first conductive part are electrically connected. The side of the second conductive part away from the first conductive part is used to connect with the electrode tab of the battery cell. The insulating layer is disposed on the side of the second substrate facing the first substrate. One end of the insulating layer is connected to the second conductive part, and the other end extends to the end of the second substrate away from the second conductive part.
[0008] Optionally, the first substrate has a first stress groove surrounding the first conductive part, and the second substrate has a second stress groove surrounding the second conductive part.
[0009] Optionally, in the thickness direction of the battery cap, the projection of the second stress groove is located inside the area enclosed by the projection of the first stress groove.
[0010] Optionally, the radius of the first stress groove is R1, the radius of the second stress groove is R2, and 3≤R1 / R2≤6.
[0011] Alternatively, 3.75 ≤ R1 / R2 ≤ 5.45.
[0012] Optionally, the radius of the second stress groove is R2, the radius of the battery cell is R3, and 8≤R3 / R2≤11.
[0013] Alternatively, 9.32 ≤ R3 / R2 ≤ 10.54.
[0014] Optionally, the second conductive part is recessed in a direction away from the first conductive part to form a limiting groove, and the first conductive part is assembled in the limiting groove.
[0015] Optionally, the battery cap includes a top cover and a sealing ring, the top cover being disposed on the side of the first base away from the second base, and the sealing ring wrapping around the end of the first base and the end of the top cover;
[0016] The explosion-proof plate includes a raised ring, which is connected to the end of the first substrate away from the first conductive part. The raised ring extends in a direction away from the second substrate and is connected to the top cover. An adaptation cavity is formed between the sealing ring, the raised ring and the top cover.
[0017] Optionally, the sealing ring includes a sealing portion and a third base. The third base wraps around the end of the first base and the end of the top cover. The sealing portion is connected to the third base and disposed in the adaptation cavity. The sealing portion is used to seal the adaptation cavity.
[0018] Optionally, the battery cap includes a sealing ring that wraps around the end of the first substrate, and a fixing cavity is formed between the sealing ring and the first substrate for accommodating adhesive.
[0019] Optionally, the battery cap includes a sealing ring that wraps around the end of the first substrate and the end of the second substrate, and the sealing ring, the first substrate, and the second substrate together form a buffer cavity.
[0020] Optionally, the sealing ring includes a third base, a buffer portion, and a fixing portion. The third base wraps around the end of the first base, the fixing portion is connected to the third base, and the fixing portion abuts against the side of the first base facing the second base. The buffer portion is connected to the third base and faces the second base. The buffer portion, the third base, the fixing portion, the first base, and the second base together form a buffer cavity.
[0021] Optionally, the thickness of the insulating layer is L1, where 50μm≤L1≤100μm.
[0022] Optionally, the insulating layer is coated on the first substrate.
[0023] Secondly, this utility model provides a single battery, comprising: a casing, a battery cell, and a battery cap as described in any of the first aspects, wherein the battery cell is assembled in the casing, and the battery cap and the battery cell are electrically connected to each other.
[0024] The beneficial effects of this utility model are as follows:
[0025] The battery cap includes an explosion-proof sheet, a perforated plate, and an insulating layer. The explosion-proof sheet includes a first substrate and a first conductive portion connected to each other. The perforated plate is disposed on one side of the explosion-proof sheet and includes a second substrate and a second conductive portion connected to each other. The second conductive portion and the first conductive portion are electrically connected. The side of the second conductive portion away from the first conductive portion is used for connection with the electrode tab of the battery cell. The insulating layer is sandwiched between the perforated plate and the explosion-proof sheet. One end of the insulating layer is connected to the second conductive portion, and the other end extends to the end of the second substrate away from the second conductive portion. The first substrate and the insulating layer are connected.
[0026] In practical applications, an insulating layer is coated on the surface of the second substrate, allowing the first substrate, the insulating layer, and the second substrate to fit tightly together, eliminating the need for additional spacers to separate them. This design effectively simplifies the battery cap structure and saves internal space. While maintaining the same external battery dimensions, the cell volume can be further increased, thereby improving the utilization rate of internal space within the individual cell, increasing battery capacity, and enhancing energy density utilization efficiency. Attached Figure Description
[0027] To more clearly illustrate the technical solutions in the embodiments of 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 only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.
[0028] Figure 1 This is a cross-sectional structural diagram of a single battery cell provided in an embodiment of the present invention;
[0029] Figure 2 This is a structural schematic diagram provided by an embodiment of the present invention for demonstrating an unassembled battery cap;
[0030] Figure 3 This is provided by the embodiment of the present utility model. Figure 2 Schematic diagram of the cross-sectional structure at point C;
[0031] Figure 4 This is provided by the embodiment of the present utility model. Figure 1 A magnified view of a portion of region B in the middle;
[0032] Figure 5This is provided by the embodiment of the present utility model. Figure 3 A magnified view of a portion of region D in the middle;
[0033] Figure 6 This is a structural schematic diagram provided by an embodiment of the present invention to illustrate an unassembled sealing ring and orifice plate;
[0034] Figure 7 This is a structural schematic diagram provided by an embodiment of the present invention to illustrate an unassembled sealing ring and cap;
[0035] Figure 8 This is a structural schematic diagram provided by an embodiment of the present invention for demonstrating an unassembled explosion-proof sheet;
[0036] Figure 9 This is a structural schematic diagram provided by this utility model for demonstrating an unassembled sealing ring.
[0037] Explanation of icon numbers:
[0038] 20. Top cover; 21. Second through hole; 30. Explosion-proof plate; 31. First substrate; 311. First stress groove; 32. First conductive part; 33. Convex ring; 40. Orifice plate; 41. Second substrate; 411. Second stress groove; 412. First through hole; 42. Second conductive part; 421. Limiting groove; 50. Pressure relief chamber; 60. Insulating layer; 70. Sealing ring; 71. Third substrate; 72. Sealing part; 73. Buffer part; 74. Fixing part; 80. Adaptation chamber; 90. Fixing chamber; 100. Buffer chamber; 110. Housing; 120. Battery cell. Detailed Implementation
[0039] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0040] Please see Figures 1 to 6 As shown, Figure 1 This is a cross-sectional structural diagram of a single battery cell provided in an embodiment of the present invention. Figure 2 This is a structural schematic diagram provided by an embodiment of the present invention for demonstrating an unassembled battery cap. Figure 3 This is provided by the embodiment of the present utility model. Figure 2 Schematic diagram of the cross-sectional structure at point C. Figure 4 This is provided by the embodiment of the present utility model. Figure 1 A magnified view of a portion of region B. Figure 5This is provided by the embodiment of the present utility model. Figure 3 A magnified view of a portion of region D. Figure 6 This is a structural schematic diagram provided by an embodiment of the present invention to show the unassembled sealing ring 70 and orifice plate 40.
[0041] This utility model provides a single battery, including a housing 110, a battery cell 120 and a battery cap. The battery cell 120 is assembled in the housing 110, and the battery cap and the tabs of the battery cell 120 are electrically connected.
[0042] Specifically, the battery cap includes an explosion-proof sheet 30, a perforated plate 40, and an insulating layer 60. The explosion-proof sheet 30 includes a first substrate 31 and a first conductive portion 32 connected to each other. The perforated plate 40 is disposed on one side of the explosion-proof sheet 30 and includes the insulating layer 60, a second substrate 41, and a second conductive portion 42 connected to each other. The second conductive portion 42 and the first conductive portion 32 are electrically connected. The side of the second conductive portion 42 away from the first conductive portion 32 is used to connect to the tab of the battery cell 120. The insulating layer 60 is disposed on the side of the second substrate 41 facing the first substrate 31. One end of the insulating layer 60 is connected to the second conductive portion 42, and the other end extends to the end of the second substrate 41 away from the second conductive portion 42. The first substrate 31 and the insulating layer 60 are connected.
[0043] In practical applications, the casing 110 is electrically connected to the negative electrode of the cell 120, while the battery cap is electrically connected to the positive electrode of the cell 120 via the second conductive part 42. When the internal pressure of a single cell becomes too high due to a fault, the first conductive part 32 separates from the second conductive part 42, thereby cutting off the circuit connection of the battery cap and improving the safety performance of the single cell. The surface of the second substrate 41 is coated with an insulating layer 60, allowing the first substrate 31, the insulating layer 60, and the second substrate 41 to fit tightly together, eliminating the need for additional spacers to separate the first substrate 31 and the second substrate 41. This design effectively simplifies the structure of the battery cap and saves internal space. While maintaining the same external dimensions of the single cell, the volume of the cell 120 can be further increased, thereby improving the utilization rate of the internal space of the single cell, increasing the capacity of the single cell, and improving the utilization efficiency of energy density.
[0044] In this embodiment, the insulating layer 60 is coated on the side of the second substrate 41 facing the first substrate 31. The material of the insulating layer 60 can be polyimide, epoxy resin, polyvinylidene fluoride, alumina or magnesium oxide ceramic coating.
[0045] In one embodiment, see Figure 2 The first substrate 31 has a first stress groove 311, which surrounds the first conductive part 32. The second substrate 41 has a second stress groove 411, which surrounds the second conductive part 42.
[0046] In practical applications, a first stress groove 311 and a second stress groove 411 are respectively provided on the first substrate 31 and the second substrate 41, so that the stress grooves are arranged around the first conductive part 32 and the second conductive part 42. When the gas pressure inside the single cell is too high due to a fault, the first conductive part 32 and the second conductive part 42 burst open at the stress groove in a direction away from the cell 120. This design can guide the conductive part to break preferentially at the stress groove under high pressure, thereby effectively cutting off the electrical connection between the battery cap and the positive electrode of the cell 120, realizing the power failure protection function. The setting of the stress groove further improves the reliability and accuracy of the explosion-proof plate 30, while ensuring that the battery cap can respond in time under extreme conditions, significantly improving the safety performance of the single cell.
[0047] Further, see Figure 4 In the thickness direction of the battery cap, the projection of the second stress groove 411 is located inside the area enclosed by the projection of the first stress groove 311.
[0048] In practical applications, when the internal gas pressure of a single battery cell is too high, the second conductive part 42 breaks first at the location of the second stress groove 411. Then, the second conductive part 42 explodes away from the cell 120 and impacts the first conductive part 32. The force-bearing location of the first conductive part 32 is within the area enclosed by the projection of the first stress groove 311, resulting in a more uniform stress distribution across the first stress groove 311. This causes the first conductive part 32 to break and explode away from the cell 120, preventing deviation or uneven fracture. This further optimizes the accuracy and reliability of the power-off protection, improves the protective effect of the battery cap, and ensures the efficient operation of the explosion-proof sheet 30, significantly improving the safety performance of the single battery system.
[0049] If the projection of the second stress groove 411 is only partially located within the area enclosed by the projection of the first stress groove 311, then when the second conductive part 42 explodes, the second conductive part 42 will impact the part of the first conductive part 32 outside the first stress groove 311, resulting in uneven stress on each part of the first stress groove 311, which may lead to only part of the first stress groove 311 breaking, thereby affecting the safety performance of the single battery system.
[0050] In this embodiment, the first stress groove 311 and the second stress groove 411 are concentrically arranged.
[0051] Optionally, the radius of the first stress groove is R1, and the radius of the second stress groove is R2, where 3 ≤ R1 / R2 ≤ 6. In this embodiment, 3.75 ≤ R1 / R2 ≤ 5.45.
[0052] Optionally, the radius of the second stress groove is R2, and the radius of the battery cell is R3, where 8 ≤ R3 / R2 ≤ 11. In this embodiment, 9.32 ≤ R3 / R2 ≤ 10.54.
[0053] In one embodiment, see Figure 4 The second conductive part 42 is recessed in a direction away from the first conductive part 32 to form a limiting groove 421, and the first conductive part 32 is assembled in the limiting groove 421.
[0054] In practical applications, by designing a limiting groove 421 on the second conductive part 42 and assembling the first conductive part 32 within the limiting groove 421, the position of the first conductive part 32 can be effectively fixed and constrained, preventing displacement or loosening caused by external forces or vibrations. During battery operation, this structure can also effectively reduce the impact of assembly errors on conductivity, ensuring the reliability of the internal circuit connections of the battery cap.
[0055] In one embodiment, see Figure 4 , Figure 5 , Figure 7 , Figure 8 and Figure 9 The second substrate 41 has a first through hole 412. The battery cap includes a top cover 20 and a sealing ring 70. The top cover 20 is located on the side of the first substrate 31 away from the second substrate 41. The top cover 20 has a second through hole 21. The top cover 20 and the first substrate 31 enclose each other to form a pressure relief cavity 50. The pressure relief cavity 50 communicates with the outside through the second through hole 21. The sealing ring 70 wraps around the end of the first substrate 31 and the end of the top cover 20. The explosion-proof sheet 30 includes a convex ring 33. The convex ring 33 is connected to the end of the first substrate 31 away from the first conductive part 32. The convex ring 33 extends in a direction away from the second substrate 41 and is connected to the top cover 20. An adaptation cavity 80 is formed between the sealing ring 70, the convex ring 33 and the top cover 20.
[0056] In practical applications, the top cover 20 is electrically connected to the positive electrode of the cell 120 via the first conductive part 32 and the second conductive part 42. During operation of the single-cell battery, the positive electrode of the external device is connected to the positive electrode of the single-cell battery via the top cover 20, while the negative electrode is connected to the negative electrode of the single-cell battery via the casing 110. When a single-cell battery malfunctions, causing excessive internal pressure, the first conductive part 32 and the second conductive part 42 will burst and separate in a direction away from the cell 120. At this time, the gas inside the cell 120 enters the pressure relief chamber 50 through the first through-hole 412, and then is discharged into the external space through the outlet of the pressure relief chamber 50, thereby effectively releasing the internal pressure of the single-cell battery, reducing the risk of single-cell battery explosion due to pressure accumulation, and significantly improving the safety performance of the single-cell battery.
[0057] The convex ring 33 connects the top cover 20 and the first base 31, which not only enhances the overall mechanical strength of the cap, but also improves the impact resistance and shock resistance of the structure, further improving the safety and reliability of the single cell.
[0058] The adaptable cavity 80 can accommodate a certain assembly error, thereby ensuring that the components can be smoothly joined and avoiding failure to assemble or damage due to excessive error.
[0059] Furthermore, referring to Figure 4 , Figure 5 and Figure 9 The sealing ring 70 includes a sealing part 72 and a third base 71. The third base 71 wraps around the end of the first base 31 and the end of the top cover 20. The sealing part 72 is connected to the third base 71 and is disposed in the adaptation cavity 80. The sealing part 72 is used to seal the adaptation cavity 80.
[0060] In practical applications, under the compression of the housing 110, the sealing part 72 of the sealing ring 70 and the third base 71 effectively wrap around the ends of the first base 31 and the top cover 20, forming a sealing structure. This ensures that the sealing part 72 is located within the adapting cavity 80 and fits tightly with it. By sealing the adapting cavity 80 with the sealing part 72, external substances are effectively prevented from entering the adapting cavity 80, while simultaneously ensuring the stability of the internal pressure.
[0061] In one embodiment, reference is made to Figure 4 , Figure 5 and Figure 9 The battery cap includes a sealing ring 70, which wraps around the end of the first base 31. A fixing cavity 90 is formed between the sealing ring 70 and the first base 31, and the fixing cavity 90 is used to contain adhesive.
[0062] In practical applications, the sealing ring 70 forms a fixing cavity 90 between itself and the first base 31 by wrapping around the end of the first base 31. This fixing cavity 90 is specifically designed to accommodate adhesive, which can effectively fill the cavity during assembly, enhancing the reliability and sealing of the connection between the sealing ring 70 and the first base 31.
[0063] In one embodiment, reference is made to Figure 4 and Figure 5 The battery cap includes a sealing ring 70, which wraps around the end of the first base 31 and the end of the second base 41. The sealing ring 70, the first base 31 and the second base 41 together form a buffer cavity 100.
[0064] In practical applications, when a single battery cell undergoes thermal expansion, the internal structure of the battery compresses the buffer section 73 into the buffer cavity 100. Through this design, the buffer cavity 100 effectively absorbs the pressure during the expansion process, reducing the direct pressure of the buffer section 73 on the perforated plate 40 and the explosion-proof sheet 30, thereby effectively preventing deformation of the perforated plate 40 and the explosion-proof sheet 30. This design improves the pressure resistance of the battery cap, ensuring that the single battery cell will not fail due to excessive internal pressure during thermal expansion, thus enhancing the safety and stability of the single battery cell.
[0065] Furthermore, referring to Figure 4 and Figure 5 The sealing ring 70 includes a third base 71, a buffer portion 73, and a fixing portion 74. The third base 71 wraps around the end of the first base 31. The fixing portion 74 is connected to the third base 71 and abuts against the side of the first base 31 facing the second base 41. The buffer portion 73 is connected to the third base 71 and faces the second base 41. The buffer portion 73, the third base 71, the fixing portion 74, the first base 31, and the second base 41 together form a buffer cavity 100.
[0066] In practical applications, the buffer portion 73 is connected to the third substrate 71 and extends towards the second substrate 41. When thermal expansion occurs inside the single cell, the buffer portion 73 can effectively absorb the pressure generated by the expansion, reducing direct compression on the first substrate 31, the second substrate 41, and other components. The third substrate 71, the buffer portion 73, the fixing portion 74, the first substrate 31, and the second substrate 41 together form a buffer cavity 100, thereby providing an effective space to alleviate the stress caused by thermal expansion and ensuring the stability and safety of the battery cap and the internal structure of the single cell. This design can improve the thermal stability of the single cell, reduce the impact of expansion pressure on the battery cap structure, and further optimize the performance of the single cell.
[0067] Optionally, refer to Figure 4 The thickness of the insulating layer 60 is L1, 50μm≤L1≤100μm.
[0068] In practical applications, the thickness of the insulating layer 60 ranges from 50 μm to 100 μm. This thickness range ensures that the insulating layer 60 can effectively isolate the electrical connection between the conductive parts of the battery cap and the cell 120, while not increasing the overall volume of the battery cap or affecting the fit of other structural components due to excessive thickness.
[0069] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a specific posture. If the specific posture changes, the directional indicator will also change accordingly.
[0070] It should also be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or may be connected to an intermediary component. When a component is referred to as being "connected to" another component, it can be directly connected to the other component or indirectly connected to the other component through an intermediary component.
[0071] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.
[0072] The above description is only a preferred embodiment of the present utility model and does not limit the patent scope of the present utility model. All equivalent structural transformations made under the inventive concept of the present utility model using the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.
Claims
1. A battery cap, characterized in that, include: Explosion-proof sheet, the explosion-proof sheet comprising a first substrate and a first conductive part connected to each other; An orifice plate is disposed on one side of the explosion-proof sheet. The orifice plate includes an insulating layer, a second substrate and a second conductive part connected to each other. The second conductive part and the first conductive part are electrically connected. The side of the second conductive part away from the first conductive part is used to connect with the electrode tab of the battery cell. The insulating layer is disposed on the side of the second substrate facing the first substrate. One end of the insulating layer is connected to the second conductive part, and the other end extends to the end of the second substrate away from the second conductive part.
2. The battery cap according to claim 1, characterized in that, The first substrate has a first stress groove that surrounds the first conductive part, and the second substrate has a second stress groove that surrounds the second conductive part.
3. The battery cap according to claim 2, characterized in that, In the thickness direction of the battery cap, the projection of the second stress groove is located inside the area enclosed by the projection of the first stress groove.
4. The battery cap according to claim 3, characterized in that, The radius of the first stress groove is R1, the radius of the second stress groove is R2, and 3≤R1 / R2≤6.
5. The battery cap according to claim 4, characterized in that, 3.75≤R1 / R2≤5.
45.
6. The battery cap according to claim 3, characterized in that, The radius of the second stress groove is R2, and the radius of the battery cell is R3, where 8 ≤ R3 / R2 ≤ 11.
7. The battery cap according to claim 6, characterized in that, 9.32≤R3 / R2≤10.
54.
8. The battery cap according to claim 1, characterized in that, The second conductive part is recessed in a direction away from the first conductive part to form a limiting groove, and the first conductive part is assembled in the limiting groove.
9. The battery cap according to claim 1, characterized in that, The battery cap includes a top cover and a sealing ring. The top cover is disposed on the side of the first base away from the second base, and the sealing ring wraps around the end of the first base and the end of the top cover. The explosion-proof sheet includes a convex ring connected to one end of the first substrate away from the first conductive part. The convex ring extends in a direction away from the second substrate and is connected to the top cover. An adaptation cavity is formed between the sealing ring, the convex ring and the top cover.
10. The battery cap according to claim 9, characterized in that, The sealing ring includes a sealing portion and a third base. The third base wraps around the end of the first base and the end of the top cover. The sealing portion is connected to the third base and disposed in the adaptation cavity. The sealing portion is used to seal the adaptation cavity.
11. The battery cap according to claim 1, characterized in that, The battery cap includes a sealing ring that wraps around the end of the first substrate. A fixing cavity is formed between the sealing ring and the first substrate to accommodate adhesive.
12. The battery cap according to claim 1, characterized in that, The battery cap includes a sealing ring that wraps around the ends of the first substrate and the second substrate, and the sealing ring, the first substrate, and the second substrate together form a buffer cavity.
13. The battery cap according to claim 12, characterized in that, The sealing ring includes a third base, a buffer portion, and a fixing portion. The third base wraps around the end of the first base. The fixing portion is connected to the third base and abuts against the side of the first base facing the second base. The buffer portion is connected to the third base and faces the second base. The buffer portion, the third base, the fixing portion, the first base, and the second base together form the buffer cavity.
14. The battery cap according to any one of claims 1-13, characterized in that, The thickness of the insulating layer is L1, where 50μm≤L1≤100μm.
15. The battery cap according to any one of claims 1-13, characterized in that, The insulating layer is coated on the first substrate.
16. A single-cell battery, characterized in that, include: The battery casing, the battery cell, and the battery cap according to any one of claims 1 to 15, wherein the battery cell is assembled in the casing, and the battery cap and the tabs of the battery cell are electrically connected.