Secondary battery
By adopting a long strip-shaped electrode connection and insulation design in the secondary battery, the problem of excessive local temperature caused by the current collector component is solved, achieving uniform heat distribution and improving battery safety, reducing production costs and extending service life.
Patent Information
- Application Number
- CN202423031839.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-09
- Publication Date
- 2025-12-12
- Estimated Expiration
- 2034-12-09
AI Technical Summary
During high-rate charging and discharging of secondary batteries, the high resistance of the current collector leads to excessively high local temperatures, causing electrochemical failure at the connection between the tab and the electrode assembly, which affects the battery capacity and lifespan.
The long strip-shaped electrode connection part is designed to ensure that it is aligned with the length of the electrode assembly and partially overlaps with it in the width direction, thereby increasing the heat transfer width. Short circuits are prevented through insulation design, and the design of the current collector is optimized to reduce material usage and resistance loss.
This achieves uniform heat distribution, improves battery thermal stability and safety, reduces production costs, extends battery life, and reduces the risk of thermal runaway caused by high temperatures.
Smart Images
Figure CN223665626U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of batteries, in particular to a secondary battery. BACKGROUND
[0002] The secondary battery is also called a rechargeable battery or a storage battery, which refers to a battery that can be activated by charging after discharging and continue to be used. Inside the secondary battery, the electrode assembly has protruding tabs, the tabs are connected to the current collecting member by welding, and the current collecting member is connected to the pole by welding, so that the current can enter or flow out of the electrode assembly from the outside. According to Joule's law, an object with resistance will generate heat when passing through the current. Therefore, during the operation of the secondary battery, the current collecting member will continue to generate heat because it bears the task of passing through the current. When the secondary battery is subjected to high-rate charging and discharging, the current collecting member will continuously generate heat, which will generate a large amount of heat that will be transmitted to the electrode assembly through the tabs, causing the temperature at the connection between the tabs and the electrode assembly to be too high, thereby causing metal precipitation and other electrochemical failures at this location, reducing the capacity and life of the battery.
[0003] At present, the products on the market are often made as small as possible in terms of cost and weight. On the one hand, this will cause the resistance of the current collecting member itself to be very high, and the current collecting member itself will generate a large amount of heat when the battery is working; on the other hand, since the current collecting member is connected to the tab by welding, the size of the current collecting member is related to the size of the tab, and a small current collecting member will also result in a small tab size, thereby causing the resistance of the tab itself to be very high. Both of the above will cause the local temperature of the battery to be too high. CONTENT OF THE UTILITY MODEL
[0004] Therefore, the present application provides a secondary battery to solve the problem of local temperature being too high in the battery.
[0005] The present application provides a secondary battery, which comprises an electrode assembly, a first connecting sheet and a second connecting sheet.
[0006] The electrode assembly is provided with a first tab and a second tab with opposite polarity on one side in the height direction. The first current collecting member and the second current collecting member each include a tab connecting portion. The tab connecting portion of the first current collecting member and the second current collecting member is provided in a long strip shape, and the length direction of the tab connecting portion is consistent with the length direction of the electrode assembly. The tab connecting portions of the first current collecting member and the second current collecting member at least partially overlap in the width direction of the electrode assembly, and are insulated from each other. The first tab is connected to the tab connecting portion of the first current collecting member, and the connection surface extends along the length direction of the tab connecting portion of the first current collecting member. The second tab is connected to the tab connecting portion of the second current collecting member, and the connection surface extends along the length direction of the tab connecting portion of the second current collecting member.
[0007] Beneficial effects: The tab connecting portion in a long strip shape is consistent with the length direction of the electrode assembly, which can increase the heat transfer width, help the heat to be evenly distributed along the length direction of the battery, reduce local hot spots, improve the thermal stability of the battery, and enable the heat generated by the electrode assembly and the tab to be quickly dissipated to the cooling device outside the battery. The overlapping design of the tab connecting portion in the width direction makes the internal structure of the battery more compact, improves the space utilization, and is beneficial to the miniaturization and light weight of the battery. By optimizing the design of the current collecting member, the use of materials can be reduced without sacrificing performance, and the production cost can be reduced.
[0008] In an optional embodiment, the ratio of the length of the connection surface of the first current collecting member and the first tab to the length of the electrode assembly is 0.5-0.9.
[0009] And / or, the ratio of the length of the connection surface of the second current collecting member and the second tab to the length of the electrode assembly is 0.5-0.9.
[0010] Beneficial effects: By limiting the ratio of the length of the connection surface to the length of the electrode assembly, sufficient current transmission path is ensured, resistance loss is reduced, and the energy conversion efficiency of the battery is improved. At the same time, a larger connection area can be achieved, which helps the heat to be evenly distributed and avoids performance degradation or safety hazards caused by local overheating.
[0011] In an optional embodiment, the tab connecting portion of the first current collecting member and the second current collecting member is provided in a long strip sheet structure. The sum of the upper surface area of the tab connecting portion of the first current collecting member and the upper surface area of the tab connecting portion of the second current collecting member is 0.5-0.96 times the upper surface area of the electrode assembly.
[0012] Beneficial effect: increase the upper surface area of the tab connecting part of the current collecting member, increase the heat dissipation surface area, help to dissipate heat to the environment faster, prolong the service life of the battery. The good heat dissipation performance brought by it reduces the internal temperature of the battery, reduces the risk of thermal runaway caused by high temperature, and improves the safety of the battery.
[0013] In an optional embodiment, the first current collecting member is provided with a plurality of mutually spaced tab connecting parts. The tab connecting part of the second current collecting member is inserted into the space between the plurality of tab connecting parts of the first current collecting member.
[0014] Beneficial effect: the mutually spaced or nested tab connecting part design can maximize the use of internal space of the battery.
[0015] In an optional embodiment, the first current collecting member and the second current collecting member are each provided with a plurality of mutually spaced tab connecting parts; the plurality of tab connecting parts of the second current collecting member and the plurality of tab connecting parts of the first current collecting member are staggered along the width direction of the electrode assembly.
[0016] Beneficial effect: the mutually spaced or nested tab connecting part design maximizes the use of internal space of the battery, provides more space for other key components, and is conducive to improving the overall performance of the battery.
[0017] In an optional embodiment, a gap is provided between any two adjacent tab connecting parts.
[0018] Beneficial effect: the provision of the gap realizes the insulation between the tab connecting parts of the first current collecting member and the second current collecting member, effectively prevents short circuit between different potentials, and improves the electrical safety of the battery. To a certain extent, it also realizes thermal isolation, prevents direct heat transfer between different tab connecting parts, and helps to control local temperature.
[0019] In an optional embodiment, at least part of the first tab passes through the gap and is connected with the tab connecting part of the first current collecting member; and the first tab is spaced apart from the tab connecting part of the second current collecting member, and / or a first insulation layer is provided between the first tab and the tab connecting part of the second current collecting member;
[0020] And / or, at least part of the second tab passes through the gap and is connected with the tab connecting part of the second current collecting member; and the second tab is spaced apart from the tab connecting part of the first current collecting member, and / or a second insulation layer is provided between the second tab and the tab connecting part of the first current collecting member.
[0021] Beneficial effects: the setting of the insulation layer can further improve the effect of preventing short circuit between different potentials.
[0022] In an alternative embodiment, the first tab is connected below the tab connecting portion of the first current collecting member, the second tab is connected below the tab connecting portion of the second current collecting member, and / or a third insulation layer is arranged between any two adjacent tab connecting portions.
[0023] Beneficial effects: by arranging the first tab below the tab connecting portion of the first current collecting member and the second tab below the tab connecting portion of the second current collecting member, the safety can be ensured by avoiding the mis-touch of the tab when inserted into the gap between the two adjacent tab connecting portions. And the insulation between the tab connecting portions of the first and second current collecting members can be more effectively achieved by the arrangement of the third insulation layer.
[0024] In an alternative embodiment, the thickness of the first current collecting member and the second current collecting member is A, wherein 0.5mm≤A≤3mm.
[0025] Beneficial effects: reasonable thickness design not only ensures that the current collecting member has sufficient mechanical strength to withstand various stresses during battery operation, but also ensures good electrical conductivity and reduces resistance loss. Appropriate thickness also helps rapid heat conduction, improving the thermal management efficiency of the battery.
[0026] In an alternative embodiment, the first current collecting member and the second current collecting member each include a pole connecting portion, the pole connecting portion of the first current collecting member is configured as an integral structure with the tab connecting portion of the first current collecting member, and the pole connecting portion of the second current collecting member is configured as an integral structure with the tab connecting portion of the second current collecting member.
[0027] Beneficial effects: the integral structure design simplifies the manufacturing process, reduces assembly steps and potential quality problems, and improves production efficiency. Reducing the failure points caused by the connection of multiple components improves the overall reliability and durability of the battery. BRIEF DESCRIPTION OF DRAWINGS
[0028] In order to more clearly illustrate the technical solutions in the specific embodiments or prior art of the present application, the drawings needed in the description of the specific embodiments or prior art will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can obtain other drawings without creative labor based on these drawings.
[0029] Figure 1 A structure schematic diagram of a secondary battery according to an embodiment of the present application;
[0030] Figure 2 A top view of a secondary battery according to an embodiment of the present application;
[0031] Figure 3 A structure diagram when a plurality of tab connecting portions are provided according to an embodiment of the present application;
[0032] Figure 4 A top view when a plurality of tab connecting portions are provided according to an embodiment of the present application.
[0033] Explanation of Reference Numerals:
[0034] 1, electrode assembly; 2, first tab; 3, second tab; 4, first current collecting member; 5, second current collecting member; 6, tab connecting portion; 7, post connecting portion; 8, first post; 9, second post. DETAILED DESCRIPTION
[0035] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described below in connection with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.
[0036] The embodiments of the present application will be described below in connection with Figures 1 to 4 .
[0037] According to the embodiments of the present application, a secondary battery is provided, which includes an electrode assembly 1, a first connecting tab and a second connecting tab.
[0038] The electrode assembly 1 is provided with a first tab 2 and a second tab 3 with opposite polarities on one side in the height direction. The first current collector 4 and the second current collector 5 each include a tab connecting portion 6. The tab connecting portion 6 of the first current collector 4 and the second current collector 5 is in a long strip structure, the length direction of the tab connecting portion 6 of the first current collector 4 and the second current collector 5 is consistent with the length direction of the electrode assembly 1, the tab connecting portion 6 of the first current collector 4 and the second current collector 5 at least partially overlaps in the width direction of the electrode assembly 1, and is insulated from each other, so that the tab connecting portion 6 of the first current collector 4 and the second current collector 5 is staggered, the first tab 2 is connected to the tab connecting portion 6 of the first current collector 4, and the connection surface extends along the length direction of the tab connecting portion 6 of the first current collector 4, so as to extend the heat transfer width of the tab connecting portion 6 of the first current collector 4 and the first tab 2. The second tab 3 is connected to the tab connecting portion 6 of the second current collector 5, and the connection surface extends along the length direction of the tab connecting portion 6 of the second current collector 5, so as to extend the heat transfer width of the tab connecting portion 6 of the second current collector 5 and the second tab 3. The height direction is the up-down direction in the Figure 1 , the length direction is the left-right direction in the Figure 2 , and the width direction is the up-down direction in the Figure 2 . For the insulation between the tab connecting portion 6 of the first current collector 4 and the tab connecting portion 6 of the second current collector 5, a gap can be provided between adjacent tab connecting portions 6, or an insulating layer can be provided on the opposite sides of adjacent tab connecting portions 6 to achieve insulation between them.
[0039] Optionally, the first current collector 4 and the first tab 2 can serve as a positive current collector and a positive tab, and the second current collector 5 and the second tab 3 can serve as a negative current collector and a negative tab.
[0040] Optionally, the first current collector 4 and the first tab 2 can serve as a negative current collector and a negative tab, and the second current collector 5 and the second tab 3 can serve as a positive current collector and a negative tab.
[0041] In this embodiment, the tab connecting portion 6 in a long strip structure is consistent with the length direction of the electrode assembly 1, which can increase the heat transfer width, help the heat to be evenly distributed along the length direction of the battery, reduce local hot spots, improve the thermal stability of the battery, and enable the heat generated by the electrode assembly 1 and the tabs to be quickly dissipated to the cooling device outside the battery. The overlapping design of the tab connecting portion 6 in the width direction makes the internal structure of the battery more compact, improves the space utilization, and is beneficial to the miniaturization and light weight of the battery. By optimizing the design of the current collector, the use of materials can be reduced without sacrificing performance, and the production cost can be reduced.
[0042] In some embodiments, the ratio of the length of the connecting surface of the first current collecting member 4 and the first tab 2 to the length of the electrode assembly 1 is 0.5-0.9.
[0043] Optionally, the ratio of the length of the connecting surface of the second current collecting member 5 and the second tab 3 to the length of the electrode assembly 1 is 0.5-0.9.
[0044] In the present embodiment, by limiting the ratio of the length of the connecting surface to the length of the electrode assembly 1, sufficient current transmission path is ensured, resistance loss is reduced, and the energy conversion efficiency of the battery is improved. At the same time, a larger connecting area can help to evenly distribute heat and avoid performance degradation or safety hazards caused by local overheating.
[0045] In some embodiments, the tab connecting portion 6 of the first current collecting member 4 and the second current collecting member 5 can be provided in a long strip-shaped sheet structure. The first current collecting member 4 and the second current collecting member 5 of the sheet structure can achieve electrical connection while also enhancing the heat dissipation effect. The ratio of the sum of the upper surface area of the tab connecting portion 6 of the first current collecting member 4 and the upper surface area of the tab connecting portion 6 of the second current collecting member 5 to the upper surface area of the electrode assembly 1 is 0.5-0.96.
[0046] In the present embodiment, by limiting the ratio of the sum of the upper surface area of the tab connecting portion 6 of the first current collecting member 4 and the upper surface area of the tab connecting portion 6 of the second current collecting member 5 to the upper surface area of the electrode assembly 1, the upper surface area of the tab connecting portion 6 of the current collecting member is increased, the heat dissipation surface area is improved, which helps to dissipate heat to the environment more quickly and prolong the service life of the battery. The good heat dissipation performance brought by it reduces the internal temperature of the battery, reduces the risk of thermal runaway caused by high temperature, and improves the safety of the battery.
[0047] In some embodiments, the first current collecting member 4 is provided with a plurality of tab connecting portions 6 spaced from each other. The tab connecting portion 6 of the second current collecting member 5 is inserted into the space between the plurality of tab connecting portions 6 of the first current collecting member 4.
[0048] Optionally, the tab connecting portion 6 of the second current collecting member 5 is arranged outside the tab connecting portion 6 of the first current collecting member 4.
[0049] Optionally, the tab connecting portion 6 of the first current collecting member 4 can be provided with 1-8.
[0050] Optionally, the tab connecting portion 6 of the second current collecting member 5 can be provided with 1-8.
[0051] In the present embodiment, the design of the mutually spaced or nested tab connecting portions 6 can maximize the use of the internal space of the battery.
[0052] In some embodiments, the first current collecting member 4 and the second current collecting member 5 are each provided with a plurality of mutually spaced tab connecting portions 6.
[0053] The plurality of tab connecting portions 6 of the second current collecting member 5 and the plurality of tab connecting portions 6 of the first current collecting member 4 are staggered along the width direction of the electrode assembly 1.
[0054] Optionally, the number of the tab connecting portions 6 of the first current collecting member 4 and the tab connecting portions 6 of the second current collecting member 5 can be consistent, and the staggered complementary form is adopted for the arrangement.
[0055] Optionally, the number of the tab connecting portions 6 of the first current collecting member 4 and the tab connecting portions 6 of the second current collecting member 5 can be inconsistent, and the staggered complementary form is adopted for the arrangement.
[0056] In the present embodiment, the mutually spaced or nested tab connecting portions 6 design maximizes the use of the internal space of the battery, provides more space for other key components (such as electrolyte, separator, etc.), and is conducive to improving the overall performance of the battery.
[0057] In some embodiments, a gap is provided between any two adjacent tab connecting portions 6.
[0058] In the present embodiment, the provision of the gap effectively prevents short circuit between different potentials, improves the electrical safety of the battery, and to some extent realizes thermal isolation, prevents direct heat transfer between different tab connecting portions 6, and helps to control the local temperature.
[0059] In some embodiments, at least part of the first tab 2 passes through the gap and is connected with the tab connecting portion 6 of the first current collecting member 4, and the first tab 2 is spaced apart from the tab connecting portion 6 of the second current collecting member 5, and / or a first insulating layer is provided between the first tab 2 and the tab connecting portion 6 of the second current collecting member 5; wherein the first insulating layer can be provided on the surface opposite to the tab connecting portion 6 of the second current collecting member 5 of the first tab 2, specifically, a tape can be attached on the first tab 2, or the first insulating layer can be provided on the side opposite to the first tab 2 of the tab connecting portion 6 of the second current collecting member 5, specifically, an insulating coating can be sprayed thereon.
[0060] In some embodiments, at least part of the second tab 3 passes through the gap and is connected with the tab connecting portion 6 of the second current collecting member 5, and the second tab 3 is spaced apart from the tab connecting portion 6 of the first current collecting member 4, and / or a second insulating layer is arranged between the second tab 3 and the tab connecting portion 6 of the first current collecting member 4. The first insulating layer can be arranged on the surface of the second tab 3 opposite to the tab connecting portion 6 of the first current collecting member 4, specifically, a tape can be attached on the second tab 3, or the first insulating layer can be arranged on the side of the tab connecting portion 6 of the first current collecting member 4 opposite to the second tab 3, specifically, an insulating coating can be sprayed on the side.
[0061] In the present embodiment, the arrangement of the insulating layer can further improve the effect of preventing short circuit between different potentials.
[0062] In some embodiments, the first tab 2 is connected below the tab connecting portion 6 of the first current collecting member 4, the second tab 3 is connected below the tab connecting portion 6 of the second current collecting member 5, and a third insulating layer is arranged between adjacent two tab connecting portions 6. The third insulating layer can be arranged on the side of each tab connecting portion 6 in the width direction, or the third insulating layer can be arranged on at least one of the two opposite sides of the adjacent two tab connecting portions 6.
[0063] In the present embodiment, the first tab 2 and the second tab 3 are arranged below the tab connecting portion 6 of the first current collecting member 4 and below the tab connecting portion 6 of the second current collecting member 5 respectively, which can avoid accidental touch of the tabs when they are inserted into the gap between the adjacent two tab connecting portions 6, and ensure safety. Meanwhile, the arrangement of the third insulating layer ensures the insulation between the tab connecting portions 6.
[0064] In some embodiments, the thickness of the first current collecting member 4 and the second current collecting member 5 is A, wherein 0.5mm≤A≤3mm.
[0065] In the present embodiment, the reasonable thickness design ensures that the current collecting member has sufficient mechanical strength to withstand various stresses during the operation of the battery, and also ensures good electrical conductivity and reduces resistance loss. The appropriate thickness also helps to quickly conduct heat and improves the thermal management efficiency of the battery.
[0066] In some embodiments, the first current collecting member 4 and the second current collecting member 5 each include a pole connecting portion 7, the pole connecting portion 7 of the first current collecting member 4 is constructed in an integral structure with the tab connecting portion 6 of the first current collecting member 4, and the pole connecting portion 7 of the second current collecting member 5 is constructed in an integral structure with the tab connecting portion 6 of the second current collecting member 5.
[0067] Optionally, the plurality of tab connecting portions 6 of the first current collecting member 4 are arranged in parallel and at intervals, and are arranged on one side of the pole connecting portion 7 of the first current collecting member 4.
[0068] Optionally, the plurality of tab connecting portions 6 of the second current collecting member 5 are arranged in parallel and at intervals, and are arranged on one side of the pole connecting portion 7 of the second current collecting member 5.
[0069] In this embodiment, the integrated structure design simplifies the manufacturing process, reduces assembly steps and potential quality problems, and improves production efficiency. Reducing the failure points caused by the connection of multiple components improves the overall reliability and durability of the battery.
[0070] In some embodiments, it further includes a first pole 8 and a second pole 9, the first pole 8 is connected to the pole connecting portion 7 of the first current collecting member 4, and the second pole 9 is connected to the pole connecting portion 7 of the second current collecting member 5.
[0071] Optionally, when charging the battery, the current flows from the first pole 8, flows through the first current collecting member 4, the first tab 2, the electrode assembly 1, the second tab 3, the second current collecting member 5, and then flows out from the second pole 9.
[0072] Optionally, when charging the battery, the current flows from the second pole 9, flows through the second current collecting member 5, the second tab 3, the electrode assembly 1, the first tab 2, the first current collecting member 4, and then flows out from the first pole 8.
[0073] In this embodiment, the reliable connection of the pole and the current collecting member ensures the stable connection between the battery and the external circuit, reduces the performance decline or safety hazards caused by poor contact. This design also facilitates the maintenance and replacement of the battery, reducing maintenance costs and time.
[0074] Although the embodiments of the present application are described in conjunction with the accompanying drawings, various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the present application, and such modifications and changes fall within the scope defined by the appended claims.
Claims
1. A secondary battery characterized by comprising: Comprise: An electrode assembly (1) provided with a first tab (2) and a second tab (3) with opposite polarity on one side in the height direction; A first current collecting member (4) and a second current collecting member (5), both of which comprise a tab connecting portion (6); Wherein, the tab connecting portion (6) of the first current collecting member (4) and the second current collecting member (5) are both provided in a long strip shape, and the length direction of the tab connecting portion (6) is consistent with the length direction of the electrode assembly (1), and the tab connecting portion (6) of the first current collecting member (4) and the second current collecting member (5) at least partially overlap in the width direction of the electrode assembly (1), and are insulated from each other; The first tab (2) is connected with the tab connecting portion (6) of the first current collecting member (4), and the connection surface extends along the length direction of the tab connecting portion (6) of the first current collecting member (4); the second tab (3) is connected with the tab connecting portion (6) of the second current collecting member (5), and the connection surface extends along the length direction of the tab connecting portion (6) of the second current collecting member (5).
2. The secondary battery according to claim 1, characterized in that: The ratio of the connection surface length of the first current collecting member (4) and the first tab (2) to the length of the electrode assembly (1) is 0.5-0.9; And / or, the ratio of the connection surface length of the second current collecting member (5) and the second tab (3) to the length of the electrode assembly (1) is 0.5-0.
9.
3. The secondary battery according to claim 1, characterized in that: The tab connecting portion (6) of the first current collecting member (4) and the second current collecting member (5) are both provided in a long strip shape; Wherein, the ratio of the sum of the upper surface area of the tab connecting portion (6) of the first current collecting member (4) and the upper surface area of the tab connecting portion (6) of the second current collecting member (5) to the upper surface area of the electrode assembly (1) is 0.5-0.
96.
4. The secondary battery according to claim 1, characterized in that: The first current collecting member (4) is provided with a plurality of spaced apart tab connecting portions (6); The tab connecting portion (6) of the second current collecting member (5) is inserted into the space of the plurality of tab connecting portions (6) of the first current collecting member (4).
5. The secondary battery according to claim 1, characterized in that: The first current collecting member (4) and the second current collecting member (5) are both provided with a plurality of spaced apart tab connecting portions (6); The plurality of tab connecting portions (6) of the second current collecting member (5) and the plurality of tab connecting portions (6) of the first current collecting member (4) are staggered in the width direction of the electrode assembly (1).
6. The secondary battery according to claim 1, characterized in that: A gap is provided between any two adjacent tab connecting portions (6).
7. The secondary battery according to claim 6, characterized in that: At least part of the first tab (2) passes through the gap and is connected to the tab connecting portion (6) of the first current collecting member (4); and the first tab (2) is spaced apart from the tab connecting portion (6) of the adjacent second current collecting member (5), and / or a first insulating layer is provided between the first tab (2) and the tab connecting portion (6) of the second current collecting member (5); And / or, at least part of the second tab (3) passes through the gap and is connected to the tab connecting portion (6) of the second current collecting member (5); and the second tab (3) is spaced apart from the tab connecting portion (6) of the first current collecting member (4), and / or a second insulating layer is provided between the second tab (3) and the tab connecting portion (6) of the first current collecting member (4).
8. The secondary battery according to claim 6, characterized by: The first tab (2) is connected below the tab connecting portion (6) of the first current collecting member (4), the second tab (3) is connected below the tab connecting portion (6) of the second current collecting member (5), and a third insulating layer is provided between any two adjacent tab connecting portions (6).
9. The secondary battery according to claim 1, characterized in that: The thickness of the first current collecting member (4) and the second current collecting member (5) is A, wherein 0.5mm≤A≤3mm.
10. The secondary battery according to claim 1, characterized by Further comprising: The first current collecting member (4) and the second current collecting member (5) each include a pole connecting portion (7), the pole connecting portion (7) of the first current collecting member (4) is configured in an integral structure with the tab connecting portion (6) of the first current collecting member (4), and the pole connecting portion (7) of the second current collecting member (5) is configured in an integral structure with the tab connecting portion (6) of the second current collecting member (5).