KR-102963916-B1 - Secondary battery and method for manufacturing thereof

Abstract

The present invention relates to a current collector, a secondary battery including the same, and a method for manufacturing the same. The current collector according to the present invention comprises a first current collector, a second current collector, and a connecting portion. The first current collector may be welded to a plurality of first electrode tabs. The second current collector may be electrically connected to the first current collector and welded to a plurality of second electrode tabs. The connecting portion may have the first current collector connected to one end and the second current collector connected to the other end, and may be provided with a current collecting projection. The current collecting projection may be made of a material different from that of the connecting portion.

Inventors

• 도진욱
• 이현희

Assignees

• 주식회사 엘지에너지솔루션

Dates

Publication Date

20260512

Application Date

20250812

Priority Date

20240819

Claims (20)

1. An electrode assembly having an electrode portion, a plurality of first electrode tabs and a plurality of second electrode tabs formed at one end of the electrode portion; and A current collector comprising: a first current collector disposed at one end of the electrode portion in a portion where the plurality of first electrode tabs and the plurality of second electrode tabs are not formed and welded to the plurality of first electrode tabs; a second current collector electrically connected to the first current collector and welded to the plurality of second electrode tabs; and a connecting portion disposed between the first current collector and the second current collector and having a current collecting projection. The plurality of first electrode tabs are bent in one direction toward the upper surface of the first current collector, and the plurality of second electrode tabs are bent in the opposite direction to the first electrode tabs toward the upper surface of the second current collector and welded respectively. The above current collection protrusion is a secondary battery formed of a material different from the above connecting part.
2. delete
3. In paragraph 1, The entire house mentioned above is, A secondary battery further equipped with a support means at the bottom of the above-mentioned current collection protrusion.
4. In paragraph 1, A secondary battery in which the first current collector extends vertically from one side of the connecting part downward, and the second current collector extends vertically from the other side of the connecting part upward.
5. In paragraph 1, A secondary battery in which the above-mentioned connecting portion is formed of Cu or Ni and the above-mentioned current collecting protrusion is formed of Al, wherein the above-mentioned connecting portion and the above-mentioned current collecting protrusion are joined by cold bonding.
6. In paragraph 3, A secondary battery in which the above-mentioned connecting portion is formed of Cu or Ni, the above-mentioned supporting means and the above-mentioned current collection protrusion are formed of Al, and the above-mentioned connecting portion and the above-mentioned supporting means are joined by cold bonding.
7. delete
8. In paragraph 1, A secondary battery having an insulating member disposed on the lower surface of the above-mentioned current collector.
9. In paragraph 1, A secondary battery having a current collector thickness of 0.5mm to 3.0mm.
10. In paragraph 1, A secondary battery having a plurality of fine grooves or a plurality of fine irregularities formed on the upper surface of the above-mentioned current collector.
11. In paragraph 1, The above electrode part It comprises a plurality of first electrode members having a first electrode tab formed at a first position and a plurality of second electrode members having a second electrode tab formed at a second position, The first electrode member and the second electrode member are a secondary battery having the same polarity.
12. A preparation step in which an electrode assembly is prepared having an electrode portion and a plurality of first electrode tabs and a plurality of second electrode tabs formed at one end of the electrode portion; A current collector placement step in which a current collector is placed at one end of the electrode portion, in a portion where the plurality of first electrode tabs and the plurality of second electrode tabs are not formed; A bending step in which the plurality of first electrode tabs are bent in one direction toward the upper surface of the first current collector of the current collector, and the plurality of second electrode tabs are bent in a direction opposite to that of the first electrode tabs toward the upper surface of the second current collector of the current collector; and A welding step in which the bent plurality of first electrode tabs and the plurality of second electrode tabs and the current collector are welded together; The entire house mentioned above is A first current collector welded to a plurality of first electrode tabs, A second current collector electrically connected to the first current collector and welded to a plurality of second electrode tabs, and One end is connected to the first current collector and the other end is connected to the second current collector, and the connecting part is provided with a current collector projection. A method for manufacturing a secondary battery in which the above-mentioned current collection protrusion is made of a material different from the above-mentioned connecting part.
13. delete
14. In Paragraph 12, The entire house mentioned above is, A method for manufacturing a secondary battery having additional support means at the bottom of the above-mentioned current collection protrusion.
15. In Paragraph 12, In the entire house mentioned above, A method for manufacturing a secondary battery in which the first current collector extends vertically from one side of the connecting part downward, and the second current collector extends vertically from the other side of the connecting part upward.
16. In Paragraph 12, A method for manufacturing a secondary battery in which the above-mentioned connecting portion is formed of Cu or Ni and the above-mentioned current collecting protrusion is formed of Al, and the above-mentioned connecting portion and the above-mentioned current collecting protrusion are joined by cold bonding.
17. In Paragraph 14, A method for manufacturing a secondary battery in which the above-mentioned connecting portion is formed of Cu or Ni, the above-mentioned supporting means and the above-mentioned current collection protrusion are formed of Al, and the above-mentioned connecting portion and the above-mentioned supporting means are joined by cold bonding.
18. In Paragraph 12, A method for manufacturing a secondary battery characterized by having an insulating member disposed on the lower surface of the above-mentioned current collector.
19. In Paragraph 12, A method for manufacturing a secondary battery in which the thickness of the above-mentioned current collector is 0.5mm to 3.0mm.
20. In Paragraph 12, A method for manufacturing a secondary battery in which a plurality of fine grooves or a plurality of fine irregularities are formed on the upper surface of the above-mentioned current collector.

Description

Secondary battery and method for manufacturing thereof The present invention relates to a secondary battery and a method for manufacturing the same. Recently, with the rapid increase in demand for portable electronic products and the full-scale development of electric vehicles, energy storage batteries, robots, and satellites, research on high-performance secondary batteries capable of repeated charging and discharging is actively underway. Secondary batteries can be manufactured in various forms depending on the shape of the battery case; for example, they can be classified into can-type secondary batteries, in which the electrode assembly is embedded in a metal can, and pouch-type secondary batteries, in which the electrode assembly is embedded in a pouch of aluminum laminate sheet. Can-type secondary batteries can be classified into cylindrical secondary batteries and prismatic secondary batteries depending on the shape of the metal can. In a secondary battery, the electrode tab of the electrode assembly is connected to the current collector by welding. The current collector is connected to the electrode terminal, and through this connection, the electrode assembly and the electrode terminal are electrically connected. The following drawings attached to this specification illustrate embodiments of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the detailed description of the invention provided below; therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings. FIG. 1 is a drawing showing a secondary battery according to one embodiment of the present invention. FIG. 2 is a drawing showing a secondary battery according to one embodiment of the present invention. FIG. 3 is a drawing showing an electrode assembly having a plurality of first and second electrode tabs formed on an electrode portion in a secondary battery according to one embodiment of the present invention. FIGS. 4a and FIGS. 4b are drawings showing a first electrode member and a second electrode member in a secondary battery according to an embodiment of the present invention. FIGS. 5A and FIGS. 5B are drawings showing a third electrode member and a fourth electrode member in a secondary battery according to an embodiment of the present invention. FIG. 6 is a drawing showing a current collector in a secondary battery according to one embodiment of the present invention. FIGS. 7A and 7B are drawings showing a current collector in a secondary battery according to one embodiment of the present invention. FIGS. 8A and FIGS. 8B are drawings showing a current collector in a secondary battery according to another embodiment of the present invention. FIGS. 9a and 9b are drawings showing a current collector in a secondary battery according to another embodiment of the present invention. FIGS. 10a and FIGS. 10b are drawings showing a current collector in a secondary battery according to another embodiment of the present invention. FIGS. 11a, FIGS. 11b, and FIGS. 11c are drawings showing an insulating member disposed at the bottom of a current collector in a secondary battery according to one embodiment of the present invention. FIG. 12 is a flowchart illustrating a method for manufacturing a secondary battery according to one embodiment of the present invention. FIG. 13 is a diagram showing a state in which a plurality of first electrode tabs and a plurality of second electrode tabs are each grouped in a secondary battery according to one embodiment of the present invention. FIGS. 14a and FIGS. 14b are drawings showing a state in which a current collector is disposed at one end of an electrode portion in a secondary battery according to one embodiment of the present invention and welded to a plurality of first electrode tabs and a plurality of second electrode tabs. FIG. 15 is a diagram showing the welding direction when welding a current collector and a first electrode tab in a secondary battery according to one embodiment of the present invention. FIG. 16 is a drawing showing the state in which a current collector and first and second electrode tabs are welded in a secondary battery according to one embodiment of the present invention. FIG. 17 is a drawing showing a state in which a cover member is placed in the portion where the current collector and the first electrode tab are welded in a secondary battery according to one embodiment of the present invention. FIG. 18 is a drawing showing a state in which a cover member is placed in the portion where the current collector and the first and second electrode tabs are welded in a secondary battery according to another embodiment of the present invention. FIG. 19 is a drawing showing the state in which a cap assembly is combined with an electrode assembly in a secondary battery according to one embodiment of the present invention. In parts of the attached drawi