CN-122000641-A - Secondary battery

Abstract

A secondary battery includes an electrode assembly including a first electrode plate including a first substrate tab arranged in a first direction and a second electrode plate including a second substrate tab arranged in a second direction opposite to the first direction, and the first and second electrode plates are provided in a stack. The electrode assembly is accommodated in a case, and a cap assembly includes a pair of collector plates electrically connected to the first and second substrate tabs, respectively, and seals the case. A greater number of the first substrate tabs are provided on the first electrode plates at the center of the stack than on the first electrode plates at the outer portions of the stack.

Inventors

• Gao Caixu

Assignees

• 三星SDI株式会社

Dates

Publication Date

20260508

Application Date

20250908

Priority Date

20241106

Claims (20)

1. 1. A secondary battery, comprising: An electrode assembly including a first electrode plate including a first substrate tab arranged in a first direction and a second electrode plate including a second substrate tab arranged in a second direction opposite to the first direction, and the first and second electrode plates being provided in a stack; A case accommodating the electrode assembly, and A cap assembly including a pair of collector plates electrically connected to the first and second substrate tabs, respectively, and sealing the case, Wherein a greater number of the first substrate tabs are provided on the first electrode plate at a center of the stack than on the first electrode plate at an outer portion of the stack.
2. 2. The secondary battery according to claim 1, wherein the first substrate tab is provided at the center of the stack such that the first substrate tab is dense at the center of the stack.
3. 3. The secondary battery according to claim 1, wherein the first electrode plates are stacked such that the first substrate tabs are arranged in a diamond shape.
4. 4. The secondary battery according to claim 1, wherein the first electrode plate in the stack comprises at least one first layer at a first side of the center of the stack, at least one second layer at the center of the stack, and at least one third layer at a second side of the center of the stack opposite the first side.
5. 5. The secondary battery according to claim 4, wherein the number of the first substrate tabs provided in the second layer is greater than the number of the first substrate tabs in the first layer, and the number of the first substrate tabs provided in the second layer is greater than the number of the first substrate tabs in the third layer.
6. 6. The secondary battery according to claim 5, wherein the number of the first substrate tabs in the first layer and the number of the first substrate tabs in the third layer are the same.
7. 7. The secondary battery according to claim 4 or 5, wherein the first substrate tab of each of the first layer, the second layer, and the third layer protrudes from the stack by the same length.
8. 8. The secondary battery according to claim 7, wherein one of the pair of current collector plates is welded to the first substrate tab, and a welding region of the one of the pair of current collector plates has a diamond shape.
9. 9. The secondary battery according to claim 4 or 5, wherein the first substrate tab of the first layer and the first substrate tab of the third layer protrude from the stack by the same length, and the first substrate tab of the first layer and the third layer protrude from the stack by different lengths than the first substrate tab of the second layer.
10. 10. The secondary battery according to claim 4, wherein a length of the first substrate tab in the second layer protruding from the stack is greater than a length of the first substrate tab in each of the first layer and the third layer protruding from the stack.
11. 11. The secondary battery according to claim 10, wherein the first substrate tab of the second layer is bent and welded to one of the pair of current collector plates.
12. 12. The secondary battery according to claim 9, wherein the first substrate tab in the second layer protrudes from the stack by a shorter length than the first substrate tabs in the first and third layers protrude from the stack.
13. 13. The secondary battery according to claim 12, wherein the first substrate tab in the first layer and the third layer is bent and welded to one of the pair of current collector plates.
14. 14. The secondary battery according to claim 4 or 5, wherein a side surface of the stack has a central region and an edge region, the first substrate tab of the first electrode plate protrudes from the side surface of the stack, the first substrate tab in the second layer is provided in the central region and the edge region, and the first substrate tab in the second layer provided in the central region and the first substrate tab in the second layer provided in the edge region have the same protruding length or different protruding lengths.
15. 15. The secondary battery according to claim 14, wherein the first substrate tab provided in the edge region in the second layer protrudes longer than the first substrate tab provided in the central region in the second layer.
16. 16. The secondary battery according to claim 15, wherein the first substrate tab provided in the edge region in the second layer is bent and welded to one of the pair of current collector plates.
17. 17. The secondary battery according to claim 4 or 5, wherein each of the first layer and the third layer includes a plurality of electrode plates, and more of the first substrate tabs are provided toward the center of the stack.
18. 18. The secondary battery according to claim 1, wherein the case includes a bottom surface and long and short side surfaces extending upward from the bottom surface, Wherein the cap assembly includes a first terminal portion electrically connected to the first electrode plate, and Wherein one of the pair of current collector plates includes a first terminal connection portion connected to the first terminal portion and a first electrode connection portion extending from the first terminal connection portion, parallel to the short side surface, and coupled to the first electrode plate.
19. 19. The secondary battery according to claim 1, wherein each of the second electrode plates includes at least one second substrate tab, and a greater number of the second substrate tabs are provided on the second electrode plate at the center of the stack than on the second electrode plate at the outer portion of the stack.
20. 20. The secondary battery according to claim 1, wherein an outermost layer of the first electrode plate has one first substrate tab.

Description

Secondary battery The present application claims priority and rights of korean patent application No. 10-2024-0155984 filed in the korean intellectual property office on day 11 and 6 of 2024, the entire disclosure of which is incorporated herein by reference. Technical Field Embodiments of the present disclosure relate to secondary batteries. Background Unlike the primary battery, the secondary battery can be charged and discharged. Low-capacity secondary batteries having a single battery cell, which are packaged in the form of a pack, are widely used for small portable electronic devices such as smart phones, function phones, laptop computers, digital cameras, video cameras, etc., while high-capacity secondary batteries are widely used as power sources for driving motors in hybrid vehicles, electric vehicles, etc., and as batteries for electric power storage. The secondary battery includes an electrode assembly composed of a positive electrode and a negative electrode, a case accommodating the electrode assembly, and an electrode terminal connected to the electrode assembly. The above information disclosed in this background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art. Disclosure of Invention The present disclosure provides a secondary battery having improved reactivity in a centrally located electrode plate by varying the number of tabs of different electrode plates, thereby allowing all electrode plates within an electrode assembly to react uniformly. However, technical problems to be solved in the embodiments of the present disclosure are not limited to the above-mentioned technical problems, and other technical problems not mentioned herein will be apparent to those skilled in the art to which the present disclosure pertains from the following description. An exemplary secondary battery according to an embodiment of the present disclosure may include an electrode assembly including a first electrode plate including a first substrate tab arranged in a first direction and a second electrode plate including a second substrate tab arranged in a second direction opposite to the first direction, and the first electrode plate and the second electrode plate being provided in a stack, a case accommodating the electrode assembly, and a cap assembly including a pair of current collector plates electrically connected to the first substrate tab and the second substrate tab, respectively, and sealing the case, wherein a greater number of the first substrate tabs is provided on the first electrode plate at a center of the stack than on the first electrode plate at an outer portion of the stack. In some examples, the first substrate tab may be provided at the center of the stack such that the first substrate tab is dense at the center of the stack. In some examples, the first electrode plates may be stacked such that the first substrate tabs are arranged in a diamond shape. In some examples, the first electrode plate in the stack includes at least one first layer at a first side of the center of the stack, at least one second layer at the center of the stack, and at least one third layer at a second side of the center of the stack opposite the first side. In some examples, the number of first substrate tabs provided in the second layer is greater than the number of first substrate tabs in the first layer, and the number of first substrate tabs provided in the second layer is greater than the number of first substrate tabs in the third layer. In some examples, the number of the first substrate tabs in the first layer and the number of the first substrate tabs in the third layer may be the same. In some examples, the first substrate tab in each of the first, second, and third layers may protrude from the stack to the same length. In some examples, one of the pair of current collector plates may be welded to the first substrate tab, and the welding region of the one of the pair of current collector plates may have a diamond shape. In some examples, the first substrate tab of the first layer and the first substrate tab of the third layer may protrude from the stack to the same length, and the first substrate tab of the first layer and the third layer may protrude from the stack to different lengths than the first substrate tab of the second layer. In some examples, the first substrate tab in the second layer may protrude from the stack by a length greater than the first substrate tab in each of the first layer and the third layer. In some examples, the first substrate tab of the second layer may be bent and welded to one of the pair of current collector plates. In some examples, the first substrate tab in the second layer may protrude from the stack by a shorter length than the first substrate tab in the first and third layers. In some examples, the first substrate tab in the first layer and the third layer ma