Electrode assemblies and their processing methods, battery cells, batteries, electrical devices

Abstract

Electrode assembly (3) and its processing method, battery cell (102), battery (100), and electrical device belong to the battery technology field. Here, the electrode assembly (3) includes an active material coated portion (31) and a tab portion (32) connected to the active material coated portion (31). The tab portion (32) includes a first laminated portion (321) and a second laminated portion (322) that are connected and installed. The first laminated portion (321) is formed by connecting the overlapping regions (Z1) of multiple laminated tab sheets (320). The second laminated portion (322) is formed by folding the first portion (3221) of the displacement region (Z2) of multiple laminated tab sheets (320) toward the remaining second portion (3222) in a direction approaching the first laminated portion (321), and then laminating and connecting them together.

Claims

1. An electrode assembly, Active material coated section, It includes a tab portion connected to the active material coating portion, The electrode assembly wherein the tab portion includes a first laminated portion and a second laminated portion that are connected and installed, the first laminated portion is formed by connecting the overlapping regions of multiple laminated tab sheets, and the second laminated portion is formed by folding a first portion of the misaligned region of the multiple laminated tab sheets toward the remaining second portion in a direction adjacent to the first laminated portion and laminating and connecting them together.

2. The electrode assembly according to claim 1, wherein the fold of the second laminate is parallel to the outer edge of the corresponding side of the tab sheet.

3. The electrode assembly according to claim 1 or 2, wherein the tab portion is formed in a trapezoidal structure with its lower base connected to the active material coating portion.

4. The electrode assembly according to claim 3, wherein the edge of the first portion adjacent to the active material coated portion is the first edge, the edge of the second portion adjacent to the active material coated portion is the second edge, there is a height difference between the first edge and the second edge, and the first edge is located on the side of the second edge away from the active material coated portion.

5. The electrode assembly according to claim 4, wherein the height difference between the first edge and the second edge is 0.8 mm to 3 mm.

6. The electrode assembly according to any one of claims 3 to 5, wherein the maximum height difference between the third edge of the first portion away from the active material coating area and the fourth edge of the second portion away from the active material coating area is 2 mm or less.

7. The electrode assembly according to any one of claims 1 to 6, wherein the tab portion extends from the first end of the active material coated portion, the first laminated portion and the second laminated portion are arranged along the longitudinal direction of the first end, and in the longitudinal direction of the first end, the length of the first portion is equal to the length of the second portion.

8. The electrode assembly according to any one of claims 1 to 7, wherein the second laminated portion is provided on both sides of the first laminated portion.

9. The electrode assembly according to any one of claims 1 to 8, wherein the thickness of the second portion tends to decrease in the direction away from the first laminated portion, and the thickness of the first portion tends to increase in the direction away from the first laminated portion.

10. The electrode assembly according to claim 9, wherein the first portion is folded and laminated on the side of the second portion where the surface changes in steps.

11. The electrode assembly according to any one of claims 1 to 10, wherein the tab sheets of both outer layers in the thickness direction of the second laminate are each installed in the same layer as the tab sheets of both outer layers in the thickness direction of the first laminate.

12. The electrode assembly according to any one of claims 1 to 11, wherein the folded portions of the multiple folded tab sheets in the second laminated portion are installed in correspondence with the multiple unfolded tab sheets, layer by layer.

13. The electrode assembly according to claim 12, wherein the edges of two tab sheets placed in the same layer in the second laminated portion are seamlessly joined.

14. The electrode assembly according to any one of claims 1 to 13, wherein the multiple layers of tab sheets of the first and second portions are joined by welding.

15. The electrode assembly according to any one of claims 1 to 14, wherein the multiple layers of tab sheets in the tab portion are connected by weld marks, and the weld marks are located in part in the first laminated portion and the remaining part in the second laminated portion.

16. A battery cell comprising a case, an electrode post, and an electrode assembly according to any one of claims 1 to 15, wherein the electrode post is installed in the case, the active material coated portion is housed within the case, and the tab portion is electrically connected to the electrode post.

17. The battery cell according to claim 16, wherein the tab portion is formed as a connection portion at a position where it is electrically connected to the pole column, and the connection portion includes a portion located in the first stacked portion and a portion located in the second stacked portion.

18. The battery cell according to claim 17, wherein the pole column has a housing groove, and at least a portion of the tab portion is housed in the housing groove.

19. A battery cell according to claim 18, wherein a housing cavity is formed within the case, the housing groove is open toward the direction away from the housing cavity, the pole column has a communication hole, the communication hole penetrates the groove wall on the side of the housing groove adjacent to the housing cavity and connects the housing cavity and the housing groove, and the tab portion is installed so as to pass through the communication hole.

20. The battery cell according to claim 19, further comprising a pole column cover plate, the pole column cover plate covering the pole column and covering the opening of the housing groove, the pole column cover plate having a liquid injection hole communicating with the housing groove, and the pole column cover plate having a sealing structure for closing the liquid injection hole.

21. A battery comprising a battery cell according to any one of claims 16 to 20.

22. An electrical device comprising the battery described in claim 21.

23. A method for processing an electrode assembly, The steps include stacking and installing multiple layers of tab sheets connected to the active material coating section, and partially offsetting them, The steps include: folding a first portion of the misaligned area of ​​the multiple layers of tab sheets towards the remaining second portion of the misaligned area in a direction adjacent to the overlapping area of ​​the multiple layers of tab sheets in the tab portion, thereby stacking the first portion and the second portion; A method for processing an electrode assembly, comprising the steps of: connecting multiple layers of tab sheets in the stacked first and second portions to form a second stacked portion; and connecting multiple layers of tab sheets in the overlapping region to form a first stacked portion, wherein the first and second stacked portions jointly form the tab portion of the electrode assembly.

24. A method for processing an electrode assembly according to claim 23, further comprising the step of welding together multiple layers of tab sheets in the first and second portions, which are folded and then laminated and installed, to form the second laminated portion.

25. A method for processing an electrode assembly according to claim 23 or 24, further comprising the steps of welding the tab portion to weld the multiple layers of tab sheets in the overlapping region to form the first laminated portion, and connecting the first laminated portion and the second laminated portion by a weld mark.

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