Collector plate structure and cylindrical power battery

Abstract

The utility model discloses a collector plate structure and a cylindrical power battery. The cylindrical power battery comprises a shell, a roll core, a top cover and a collector plate structure, the roll core is sleeved with the shell, the shell is covered with the top cover, the end, close to the top cover, of the roll core is provided with a positive electrode full-tab welding area and a negative electrode full-tab welding area, and a pole is arranged on the top cover. The collector plate structure comprises a positive electrode current collector, a negative electrode current collector and an insulator, the positive electrode current collector and the negative electrode current collector are connected into a whole at intervals through the insulator, the positive electrode current collector is configured to be welded with the pole and the positive electrode full-tab welding area, and the negative electrode current collector is configured to be welded with the negative electrode full-tab welding area and the shell or the top cover. The positive current collector and the negative current collector can be welded at one end of the battery at the same time, so that the internal space of the battery is saved, the space utilization rate of the battery is improved, the series resistance of the battery is reduced, and the energy utilization rate of the battery is improved.

Description

Technical Field

[0001] The present technology relates to the field of new energy power batteries, and in particular to a current collecting plate structure and a cylindrical power battery. Background Art

[0002] At present, cylindrical power batteries such as lithium-ion / sodium-ion batteries have gradually become the mainstream products in the new energy industry due to their high energy density, good capacity consistency, and support for high-rate charging and discharging. With the popularization of new energy vehicles, people's pursuit of long battery life has put forward higher and higher requirements on indicators such as the structural simplicity and energy density of power batteries.

[0003] Conventional cylindrical power battery structures usually have positive and negative collector plates at both ends of the winding core. Such solutions require space to be reserved at both ends of the positive and negative electrodes to place the collector plates, resulting in a large waste of battery space. As the module structure of cylindrical power batteries becomes simpler and longer, if the positive and negative collector plates are still set at both ends of the winding core, the battery will be connected to the shell resistance, resulting in high battery resistance and easy heat generation. Utility Model Content

[0004] The present application aims to provide a current collecting plate structure and a cylindrical power battery, which can save the internal space of the battery, improve the space utilization rate of the battery, reduce the resistance connected in series with the battery, and improve the energy utilization rate of the battery.

[0005] To achieve the above-mentioned purpose, the present application provides a current collecting plate structure for a cylindrical power battery, the battery comprising a shell, a winding core sleeved in the shell, a top cover covered on the shell and the current collecting plate structure, the winding core having a positive electrode full-pole lug welding area and a negative electrode full-pole lug welding area at one end close to the top cover, a pole is provided on the top cover, the current collecting plate structure comprises a positive electrode current collector, a negative electrode current collector and an insulator, the insulator connects the positive electrode current collector and the negative electrode current collector into a whole at intervals, the positive electrode current collector is configured to be welded to the pole post and the positive electrode full-pole lug welding area, and the negative electrode current collector is configured to be welded to the negative electrode full-pole lug welding area and the shell or the top cover.

[0006] In the present application, the current collector disc structure includes a positive current collector, a negative current collector, and an insulator that connects the positive current collector and the negative current collector at intervals. The positive current collector and the negative current collector are respectively welded to the positive full-pole ear welding area and the negative full-pole ear welding area located at one end of the winding core close to the top cover, so that the positive current collector and the negative current collector can be simultaneously arranged at the same end of the battery, saving the internal space of the battery and improving the space utilization of the battery. At the same time, it can also reduce the resistance connected in series with the battery and improve the energy utilization of the battery.

[0007] Optionally, the insulator connects the positive electrode current collector and the negative electrode current collector into one body by injection molding.

[0008] Optionally, the positive electrode current collector and the negative electrode current collector are completely separated by the insulator.

[0009] Optionally, the outer edge of the positive electrode current collector is configured to roughly match the outer edge of the positive electrode full tab welding area, and the outer edge of the negative electrode current collector is configured to roughly match the outer edge of the negative electrode full tab welding area.

[0010] Optionally, the positive electrode current collector and the negative electrode current collector are substantially fan-shaped and arranged opposite to each other.

[0011] Optionally, the positive electrode current collector protrudes toward the top cover to form a convex portion, and the convex portion is used for welding to the pole.

[0012] Optionally, the convex portion is formed at one end of the positive electrode current collector by stamping, one side edge of the convex portion is connected to the main body of the positive electrode current collector, and a portion of the convex portion not connected to the main body is suspended.

[0013] Optionally, a through hole corresponding to the convex portion is provided on the insulator, and a hole wall of the through hole does not cover a connecting arm between the convex portion and the main body but covers an inner edge of the negative electrode current collector.

[0014] Optionally, the negative electrode current collector extends toward the top cover near an edge of the shell to form an extension portion, and the extension portion is configured to be welded to a side wall of the shell.

[0015] Optionally, the extension portion is provided with at least one notch, and the notch is used to release stress.

[0016] Optionally, the insulator is provided with a plurality of through holes.

[0017] To achieve the above-mentioned purpose, the present application also provides a cylindrical power battery, including a shell, a winding core sleeved in the shell, a top cover covered on the shell and the above-mentioned current collecting plate structure, the winding core having a positive electrode full-pole lug welding area and a negative electrode full-pole lug welding area at one end close to the top cover, a pole is provided on the top cover, the positive current collector is welded to the pole post and the positive electrode full-pole lug welding area, and the negative current collector is welded to the negative electrode full-pole lug welding area and the shell or the top cover.

[0018] In the present application, the current collector disc structure includes a positive current collector, a negative current collector, and an insulator that connects the positive current collector and the negative current collector at intervals. The positive current collector and the negative current collector are respectively welded to the positive full-pole ear welding area and the negative full-pole ear welding area located at one end of the winding core close to the top cover, so that the positive current collector and the negative current collector can be simultaneously arranged at the same end of the battery, saving the internal space of the battery and improving the space utilization of the battery. At the same time, it can also reduce the resistance connected in series with the battery and improve the energy utilization of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the three-dimensional structure of the current collecting plate structure of an embodiment of the present application.

[0020] Figure 2 It is another three-dimensional structural schematic diagram of the current collecting plate structure of the embodiment of the present application.

[0021] Figure 3 for Figure 1 Section view along line AA.

[0022] Figure 4 for Figure 1 Another cross-sectional view along line AA.

[0023] Figure 5 It is a schematic diagram of the three-dimensional structure of the cylindrical power battery according to an embodiment of the present application.

[0024] Figure 6 This is a schematic diagram of the exploded structure of the cylindrical power battery of an embodiment of the present application.

[0025] Figure 7 for Figure 5 Cross-sectional view along line BB. DETAILED DESCRIPTION

[0026] In order to explain the technical content, structural features, achieved objectives and effects of the present application in detail, the following is a detailed description in conjunction with the implementation methods and the accompanying drawings.

[0027] See also Figures 1 to 6The present application discloses a current collecting plate structure 4 for a cylindrical power battery. The battery comprises a shell 1, a winding core 2 sleeved in the shell 1, a top cover 3 covered on the shell 1, and a current collecting plate structure 4. The end of the winding core 2 close to the top cover 3 has a positive electrode full-pole lug welding area 21 and a negative electrode full-pole lug welding area 22. The top cover 3 is provided with a pole 6. The current collecting plate structure 4 comprises a positive electrode current collector 41, a negative electrode current collector 42, and an insulator 43. The insulator 43 connects the positive electrode current collector 41 and the negative electrode current collector 42 to form a whole at intervals. The positive electrode current collector 41 is configured to be welded to the pole 6 and the positive electrode full-pole lug welding area 21, and the negative electrode current collector 42 is configured to be welded to the negative electrode full-pole lug welding area 22 and the shell 1 or the top cover 3. In some embodiments, the negative electrode current collector 42 is welded to the shell 1 (such as Figure 7 As shown), in other embodiments, the negative electrode current collector 42 can be welded to the top cover 3.

[0028] In some embodiments, the insulator 43 is connected to the positive electrode current collector 41 and the negative electrode current collector 42 by injection molding. Of course, the insulator 43, the positive electrode current collector 41 and the negative electrode current collector 42 can also be connected to each other by other means such as assembly.

[0029] In some embodiments, the positive electrode current collector 41 and the negative electrode current collector 42 are completely separated by the insulator 43 , thereby more effectively preventing the positive electrode current collector 41 and the negative electrode current collector 42 from being directly connected and short-circuited.

[0030] In some embodiments, the outer edge of the positive electrode current collector 41 is configured to be roughly matched with the outer edge of the positive electrode full-polar lug welding area 21, and the outer edge of the negative electrode current collector 42 is configured to be roughly matched with the outer edge of the negative electrode full-polar lug welding area 22. Specifically, the "outer edge of the negative electrode current collector 42" herein does not include the extension 421 and the area extending out of the extension 421. This structure is conducive to increasing the conduction area between the positive electrode current collector 41 and the positive electrode full-polar lug welding area 21 and the negative electrode current collector 42 and the negative electrode full-polar lug welding area 22.

[0031] Specifically, the positive electrode current collector 41 and the negative electrode current collector 42 are substantially fan-shaped and arranged opposite to each other. Of course, this arrangement method is an optional arrangement method. The shape of the positive electrode current collector 41 and the negative electrode current collector 42 can also be rectangular, etc., without limitation.

[0032] In some embodiments, the positive electrode current collector 41 protrudes toward the top cover 3 to form a convex portion 411, and the convex portion 411 is welded to the pole 6. The provision of the convex portion 411 facilitates welding of the positive electrode current collector 41 and the pole 6.

[0033] Specifically, the convex portion 411 can be formed at one end of the positive electrode current collector 41 by stamping or the like, and one side edge of the convex portion 411 is connected to the main body 412 of the positive electrode current collector 41, and the portion of the convex portion 411 that is not connected to the main body 412 is suspended. Through this arrangement, the connecting arm 413 between the convex portion 411 and the main body 412 can be elastically deformed, and then the stress transmitted by the convex portion 411 and the main body 412 can be released by the elastic deformation of the connecting arm 413. Of course, the convex portion 411 is not limited to being formed by stamping the positive electrode current collector 41, nor is it limited to being integrally grown on the positive electrode current collector 41. For example, the convex portion 411 can also be connected to the main body 412 after the production is completed.

[0034] See also Figures 2 to 4 Preferably, the insulator 43 is provided with a through hole 432 corresponding to the protrusion 411, and the hole wall of the through hole 432 does not cover the connecting arm 413 between the protrusion 411 and the main body 412, but covers the inner edge of the negative electrode current collector 42. Since the hole wall of the through hole 432 does not cover the connecting arm 413 between the protrusion 411 and the main body 412, it can avoid affecting the elastic deformable function of the connecting arm 413, and since the hole wall of the through hole 432 covers the inner edge of the negative electrode current collector 42, it can prevent the positive electrode current collector 41 and the negative electrode current collector 42 from being connected and short-circuiting.

[0035] See also Figure 1 and Figure 4 Optionally, the protrusion 411 is substantially circular, with a diameter D of 4.5 to 7 mm, and a height H of the connecting arm 413 of 0.3 to 0.7 mm.

[0036] In some embodiments, the negative electrode current collector 42 extends from the edge of the housing 1 toward the top cover 3 to form an extension portion 421, and the extension portion 421 is configured to be welded to the side wall of the housing 1. In different embodiments, an extension portion 421 welded to the top cover 3 may also be provided.

[0037] Optionally, the extension portion 421 is provided with at least one notch 422 , and the notch 422 is used to release stress.

[0038] See also Figure 4 Optionally, the extension portion 421 is an L-shaped vertical edge, and the height W may be 1.0 to 2.5 mm.

[0039] In some embodiments, the insulator 43 is provided with a plurality of through holes 431 , which can facilitate the infiltration of the electrolyte and reduce the amount of raw materials used for the insulator 43 , thereby reducing the weight of the battery and lowering the production cost.

[0040] In the present application, the current collecting disc structure 4 includes a positive current collector 41, a negative current collector 42, and an insulator 43 that connects the positive current collector 41 and the negative current collector 42 at intervals. Among them, the positive current collector 41 and the negative current collector 42 are respectively welded to the positive full-pole ear welding area 21 and the negative full-pole ear welding area 22 located at one end of the winding core 2 close to the top cover 3, so that the positive current collector 41 and the negative current collector 42 can be set at the same end of the battery at the same time, saving the internal space of the battery, improving the space utilization rate of the battery, and at the same time reducing the resistance of the battery in series, and improving the energy utilization rate of the battery.

[0041] See also Figures 5 to 7 The present application discloses a cylindrical power battery, comprising a shell 1, a winding core 2 sleeved in the shell 1, a top cover 3 covered on the shell 1 and the above-mentioned current collecting plate structure 4, the winding core 2 has a positive electrode full-pole lug welding area 21 and a negative electrode full-pole lug welding area 22 at one end close to the top cover 3, a pole 6 is provided on the top cover 3, a positive electrode collector 41 is welded to the pole 6 and the positive electrode full-pole lug welding area 21, and a negative electrode collector 42 is welded to the negative electrode full-pole lug welding area 22 and the shell 1.

[0042] In some embodiments, the cylindrical power battery further includes a liquid injection hole 11 disposed at the bottom of the shell 1, and the liquid injection hole 11 corresponds to the central hole 5 of the winding core 2. When welding the collector plate structure 4, the welding fixture can pass through the liquid injection hole 11, the central hole 5 and the through hole 432 to support the convex portion 411, and weld the convex portion 411 and the pole 6. Specifically, laser penetration welding is used for welding.

[0043] In the present application, the current collecting disk structure 4 includes a positive electrode collector 41, a negative electrode collector 42 and an insulator 43 which connects the positive electrode collector 41 and the negative electrode collector 42 at intervals. The positive electrode collector 41 and the negative electrode collector 42 are respectively welded to the positive electrode full-ear welding area 21 and the negative electrode full-ear welding area 22 located at one end of the winding core 2 close to the top cover 3, so that the positive electrode collector 41 and the negative electrode collector 42 can be simultaneously arranged at the same end of the battery, which saves the internal space of the battery, improves the space utilization of the battery, and can also reduce the resistance connected in series with the battery, thereby improving the energy utilization of the battery.

[0044] In order to make the present application more easily understood, the optional assembly process of the cylindrical power battery in the accompanying drawings is briefly described below, which should not be regarded as a limitation to the present application.

[0045] First, a positive electrode full tab welding area 21 and a negative electrode full tab welding area 22 are provided at one end of the winding core 2 , which are spaced apart from each other.

[0046] Next, the positive electrode current collector 41 of the current collecting plate structure 4 is welded to the positive electrode full-tab welding area 21 by laser welding, and the negative electrode current collector 42 of the current collecting plate structure 4 is welded to the negative electrode full-tab welding area 22 by laser welding.

[0047] Next, the winding core 2 is inserted into the shell 1 , so that the end of the winding core 2 welded with the current collecting plate structure 4 faces the shell opening of the shell 1 .

[0048] Next, the extension portion 421 of the negative electrode current collector 42 is connected to the inner wall of the case 1 by laser welding or ultrasonic welding.

[0049] Next, the top cover 3 and the shell opening of the shell 1 are sealed and fixed by laser welding.

[0050] Next, a welding fixture is passed through the injection hole 11 , the center hole 5 and the through hole 432 , and the protrusion 411 is supported to make the pole 6 and the protrusion 411 fit together, and the pole 6 and the protrusion 411 are connected by laser penetration welding.

[0051] The above disclosure is only a preferred example of the present application and cannot be used to limit the scope of rights of the present application. Therefore, equivalent changes made according to the claims of the present application are all within the scope covered by the present application.

Claims

1. A current collecting plate structure for a cylindrical power battery, the battery comprising a shell, a winding core sleeved in the shell, a top cover covered on the shell and the current collecting plate structure, the winding core having a positive electrode full-pole lug welding area and a negative electrode full-pole lug welding area at one end close to the top cover, and a pole is provided on the top cover, characterized in that: The current collector structure includes a positive electrode collector, a negative electrode collector and an insulator, wherein the insulator connects the positive electrode collector and the negative electrode collector to form a whole with a gap between them, the positive electrode collector is configured to be welded to the pole and the positive electrode full-earth tab welding area, and the negative electrode collector is configured to be welded to the negative electrode full-earth tab welding area and the shell or the top cover.

2. The current collecting plate structure according to claim 1, characterized in that: The insulator connects the positive electrode current collector and the negative electrode current collector into one body through injection molding.

3. The current collecting plate structure according to claim 1, characterized in that: The positive electrode current collector and the negative electrode current collector are completely separated by the insulator.

4. The current collecting plate structure according to claim 1, characterized in that: The outer edge of the positive electrode current collector is configured to roughly match the outer edge of the positive electrode full-tab welding area, and the outer edge of the negative electrode current collector is configured to roughly match the outer edge of the negative electrode full-tab welding area.

5. The current collecting plate structure according to claim 4, characterized in that: The positive electrode current collector and the negative electrode current collector are substantially fan-shaped and arranged opposite to each other.

6. The current collecting plate structure according to claim 1, characterized in that: The positive electrode current collector protrudes toward the top cover to form a convex portion, and the convex portion is used for welding with the pole.

7. The current collecting plate structure according to claim 6, characterized in that: The convex portion is formed at one end of the positive electrode current collector by stamping, one side edge of the convex portion is connected to the main body of the positive electrode current collector, and a portion of the convex portion not connected to the main body is suspended.

8. The current collecting plate structure according to claim 7, characterized in that: The insulator is provided with a through hole corresponding to the convex portion, and the hole wall of the through hole does not cover the connecting arm between the convex portion and the main body but covers the inner edge of the negative electrode collector.

9. The current collecting plate structure according to claim 1, characterized in that: The negative electrode current collector extends toward the top cover from an edge position close to the shell to form an extension portion, and the extension portion is configured to be welded to a side wall of the shell.

10. The current collecting plate structure according to claim 9, characterized in that: The extension portion is provided with at least one notch, and the notch is used to release stress.

11. The current collecting plate structure according to claim 1, characterized in that: The insulator is provided with a plurality of through holes.

12. A cylindrical power battery, characterized in that: It comprises a shell, a winding core sleeved in the shell, a top cover covered on the shell and a current collecting disk structure as claimed in any one of claims 1 to 8, wherein one end of the winding core close to the top cover has a positive electrode full-pole lug welding area and a negative electrode full-pole lug welding area, a pole is provided on the top cover, the positive current collector is welded to the pole and the positive electrode full-pole lug welding area, and the negative current collector is welded to the negative electrode full-pole lug welding area and the shell or the top cover.

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