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KR-20260067448-A - CURRENT COLLECTOR COMPRISING CONDUCTIVE PRIMER LAYER AND ALL-SOLID-STATE BATTERY COMPRISING THE SAME

KR20260067448AKR 20260067448 AKR20260067448 AKR 20260067448AKR-20260067448-A

Abstract

The present invention relates to a current collector having a primer layer comprising a conductive material and a binder having a three-dimensional network structure, an electrode for an all-solid-state battery comprising said current collector, an all-solid-state battery, and a method for manufacturing said electrode for an all-solid-state battery.

Inventors

  • 문승환
  • 정경준
  • 이소리
  • 최슬기
  • 이주연
  • 김종정

Assignees

  • 현대자동차주식회사
  • 기아 주식회사

Dates

Publication Date
20260513
Application Date
20241104

Claims (20)

  1. Listing; and A primer layer formed on the above-mentioned substrate; comprising, The primer layer comprises a conductive material and a binder with a three-dimensional network structure, and A current collector comprising a binder of the above-mentioned three-dimensional network structure that includes cross-linking of a polymer having unsaturated bonds and a vulcanizing agent.
  2. In paragraph 1, The above conductive material is a point-type conductive material, which is a current collector.
  3. In paragraph 1, A current collector having a BET specific surface area of the above conductive material of 50 m² /g or more and 100 m² /g or less.
  4. In paragraph 1, A current collector in which the polymer having the above-mentioned unsaturated bond is one or more selected from the group consisting of styrene-butadiene rubber, nitrile-butadiene rubber, and butadiene rubber.
  5. In paragraph 1, The above vulcanizing agent is a current collector comprising a sulfur donor and a vulcanizing promoter.
  6. In paragraph 5, A current collector in which the weight ratio between the sulfur donor and the vulcanization accelerator is 1:1 to 1:5.
  7. In paragraph 1, A current collector in which the weight ratio between the polymer having the above-mentioned unsaturated bonds and the vulcanizing agent is 5:1 to 10:1.
  8. In paragraph 1, A current collector having a weight ratio of 1:1 to 1:4 between the conductive material and the binder of the three-dimensional network structure.
  9. In paragraph 1, A current collector having a primer layer thickness of 0.1㎛ or more and 20㎛ or less.
  10. In paragraph 1, The above-described current collector comprises one or more metals selected from the group consisting of Al, Ti, Ni, Cu, and SUS.
  11. In paragraph 1, A current collector having a thickness of 3㎛ or more and 30㎛ or less as described above.
  12. In paragraph 1, The form of the above-described current collector is foil, mesh, or foam.
  13. A collection unit according to any one of paragraphs 1 through 12; It includes an electrode layer formed on the above current collector; The electrode for an all-solid-state battery, wherein the electrode layer comprises an electrode active material and a solid electrolyte.
  14. Step (S1) of preparing a primer layer slurry comprising a conductive material, a polymer having unsaturated bonds, and a vulcanizing agent; Step (S2) of forming a primer layer by applying and drying the above primer layer slurry onto a substrate to a certain thickness; Step (S3) of forming an electrode layer by further applying and drying an electrode slurry containing an electrode active material and a solid electrolyte on the primer layer; and A method for manufacturing an electrode for an all-solid-state battery according to claim 13, comprising the step (S4) of drying under temperature conditions of 120°C or higher and 180°C or lower to proceed with cross-linking between a polymer having unsaturated bonds and a vulcanizing agent.
  15. In Paragraph 14, A method for manufacturing an electrode for an all-solid-state battery, wherein the weight ratio between the electrode active material and the solid electrolyte in the electrode slurry is 3:1 to 5:1.
  16. In Paragraph 14, A method for manufacturing an electrode for an all-solid-state battery, wherein, based on 100 parts by weight of the total of all materials included in the electrode slurry, the binder is included in an amount of 1 to 3 parts by weight, the dispersant in an amount of 0 to 1 part by weight, and the conductive material in an amount of 1 to 2 parts by weight.
  17. In Paragraph 14, The above primer layer slurry and electrode slurry contain an organic solvent, and A method for manufacturing an electrode for an all-solid-state battery, wherein the above organic solvent is one or more selected from the group consisting of butyl butyrate, hexyl butyrate, benzyl acetate o-xylene, toluene, dibromomethane, and anisole.
  18. In Paragraph 14, A method for manufacturing an electrode for an all-solid-state battery, wherein the drying in step S2 above is performed at 90°C to 120°C for 60 minutes or less.
  19. In Paragraph 14, A method for manufacturing an electrode for an all-solid-state battery, wherein the drying in step S3 above is performed at 90°C to 120°C for 60 minutes or less.
  20. A solid-state battery comprising an electrode for a solid-state battery according to Paragraph 13.

Description

Current collector comprising a conductive primer layer and all-solid-state battery comprising the same The present invention relates to a current collector that can maximize adhesion with an electrode layer by providing a primer layer comprising a conductive material and a binder having a three-dimensional network structure on one side of a substrate, thereby improving the performance and durability of the all-solid-state battery, an electrode for an all-solid-state battery including the same, and an all-solid-state battery. All-solid-state batteries are gaining attention as a new type of battery capable of replacing conventional lithium-ion batteries due to their advantages in ensuring high energy density and safety. However, since all-solid-state batteries utilize solids as electrolytes, minimizing resistance at the interfaces between the current collector and the electrode layer, as well as between the electrode layer and the solid electrolyte layer, is an essential task for enhancing cell characteristics. In particular, low adhesion at the interface between the current collector and the electrode layer can lead to the easy detachment of solid particles from the electrode during processing and result in increased interfacial resistance due to reduced contact area during repeated charge-discharge cycles. These issues have a more significant adverse effect as the charge-discharge process continues, reducing charge-discharge efficiency by decreasing the movement paths of electrons and ions and rapidly degrading the overall durability of the battery, thereby significantly degrading the electrochemical performance of the all-solid-state battery. Therefore, a new current collector design is required that can maximize adhesion at the interface between the electrode layer and the current collector while maintaining the inherent performance of the current collector. The present invention will be described in more detail below. Terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention. The whole house The present invention provides a current collector comprising a substrate and a primer layer formed on the substrate, wherein the primer layer comprises a conductive material and a binder having a three-dimensional network structure, and the binder having a three-dimensional network structure comprises cross-linking of a polymer having unsaturated bonds and a vulcanizing agent. The current collector of the present invention can maximize contact between the electrode layer and the current collector by ensuring that a primer layer formed on a substrate comes into contact with the electrode layer, thereby achieving low interfacial resistance. In addition, the binder included in the primer layer has a three-dimensional network structure, which minimizes particle movement within the primer layer during the charging and discharging process, thereby improving adhesion between the primer layer and the electrode layer. Furthermore, the primer layer includes a conductive material to provide excellent electrical conductivity, which can maximize the effect of improving adhesion and thereby improve the lifespan characteristics of the electrode. Primer layer The primer layer included in the current collector of the present invention is characterized by comprising a conductive material and a binder having a three-dimensional network structure. The above conductive material is intended to ensure electrical conductivity of the primer layer and may be a point-type conductive material. As the point-type conductive material, one or more selected from the group consisting of carbon black, acetylene black, Ketjen black, and furnace black may be used. In addition, the BET specific surface area of the conductive material may be 50 m² /g or more and 100 m² /g or less, and preferably 55 m² /g or more, 60 m² /g or more, or 65 m² /g or more, and may be 95 m² /g or less, 90 m² /g or less, 85 m² /g or less, or 80 m² /g or less. In this way, when using a point-type conductive material with a low BET specific surface area, the binder is mainly distributed on the upper part of the primer layer, and since the binder distributed on the upper part of the primer layer can bond more strongly with the electrode layer, the adhesion between the current collector and the electrode layer can be improved. The binder of the above three-dimensional network structure may include cross-linking between a polymer having unsaturated bonds and a vulcanizing agent. The polymer having the above-mentioned unsaturated bond may be a butadiene rubber-based polymer, and more specifically, may be one or more selected from the group consisting of styrene-butadiene rubber, n