Method for manufacturing electrode for storage battery

Patent metadata

Field	Value
Publication number	US-9490472-B2
Application number	US-201414220310-A
Country	US
Kind code	B2
Filing date	Mar 20, 2014
Priority date	Mar 28, 2013
Publication date	Nov 8, 2016
Grant date	Nov 8, 2016

Abstract

To provide a storage battery electrode including an active material layer with high density that contains a smaller percentage of conductive additive. To provide a storage battery having a higher capacity per unit volume of an electrode with the use of the electrode for a storage battery. A slurry that contains an active material and graphene oxide is applied to a current collector and dried to form an active material layer over the current collector, the active material layer over the current collector is rolled up together with a spacer, and a rolled electrode which includes the spacer are immersed in a reducing solution so that graphene oxide is reduced.

First claim

What is claimed is:

1. A method for manufacturing an electrode for a storage battery, the method comprising the steps of:
forming a stack of an active material layer and a current collector;
rolling up the stack of the active material layer and the current collector together with a porous support to form a rolled stack comprising the porous support after forming the stack of the active material layer and the current collector;
immersing the rolled stack in a solution comprising a reducing agent after forming the rolled stack; and
separating the porous support from the stack of the active material layer and the current collector.

2. The method according to claim 1 , wherein the active material layer comprises graphene oxide.

3. The method according to claim 1 , wherein the solution comprising the reducing agent further comprises water.

4. The method according to claim 3 , wherein the solution comprising the reducing agent further comprises a solvent which has a higher boiling point than water.

5. The method according to claim 1 , wherein the solution comprising the reducing agent further comprises a pH adjuster.

6. The method according to claim 1 , further comprising the steps of:
washing the active material layer after immersing the rolled stack; and
drying the active material layer after the washing step.

7. The method according to claim 1 , wherein the reducing agent is any one of materials selected from ascorbic acid, hydrazine, dimethyl hydrazine, hydroquinone, sodium boron hydride, tetra butyl ammonium bromide, LiAlH 4 , N,N-diethylhydroxylamine and a derivative thereof.

8. The method according to claim 1 , wherein the active material layer comprises a positive electrode active material.

9. A method for manufacturing an electrode for a storage battery, the method comprising the steps of:
applying a slurry which comprises an active material and graphene oxide to a current collector;
drying the slurry to form a stack of an active material layer and the current collector;
rolling up the stack of the active material layer and the current collector together with a porous support to form a rolled stack comprising the porous support after forming the stack of the active material layer and the current collector;
immersing the rolled stack in a solution comprising a reducing agent after forming the rolled stack; and
separating the porous support from the stack of the active material layer and the current collector.

10. The method according to claim 9 , wherein the graphene oxide is reduced by the immersion step so that graphene is formed.

11. The method according to claim 9 , wherein the solution comprising the reducing agent further comprises water.

12. The method according to claim 11 , wherein the solution comprising the reducing agent further comprises a solvent which has a higher boiling point than water.

13. The method according to claim 9 , wherein the reducing agent is any one of materials selected from ascorbic acid, hydrazine, dimethyl hydrazine, hydroquinone, sodium boron hydride, tetra butyl ammonium bromide, LiAlH 4 , N,N-diethylhydroxylamine and a derivative thereof.

14. The method according to claim 13 , wherein the reducing agent is ascorbic acid.

15. The method according to claim 9 , further comprising the steps of:
washing the active material layer after immersing the rolled stack; and
drying the active material layer after the washing step.

16. The method according to claim 15 , wherein the washing step is performed by spraying a washing solution.

17. The method according to claim 9 , wherein the active material layer comprises a positive electrode active material.

18. A method for manufacturing an electrode for a storage battery, the method comprising the steps of:
applying a slurry which comprises an active material and graphene oxide to a current collector;
drying the slurry to form a stack of an active material layer and the current collector;
rolling up the stack of the active material layer and the current collector to form a rolled stack after forming the stack of the active material layer and the current collector;
immersing the rolled stack in a solution comprising a reducing agent to reduce graphene oxide after forming the rolled stack;
washing the stack of the active material layer and the current collector after immersing the rolled stack; and
drying the stack of the active material layer and the current collector after the washing step,
wherein the solution comprising the reducing agent further comprises water and a solvent which has a higher boiling point than water.

19. The method according to claim 18 , wherein the reducing agent is any one of materials selected from ascorbic acid, hydrazine, dimethyl hydrazine, hydroquinone, sodium boron hydride, tetra butyl ammonium bromide, LiAlH 4 , N,N-diethylhydroxylamine and a derivative thereof.

20. The method according to claim 18 , wherein the active material layer comprises a positive electrode active material.

21. The method according to claim 18 , wherein the solution comprising the reducing agent further comprises a pH adjuster.

Assignees

• Semiconductor Energy Lab

Inventors

• Nanba Kenryo
• Yukawa Mikio

Classifications

• B32B2317/12

  Paper, e.g. cardboard · CPC title

• H01M4/0435

  Rolling or calendering · CPC title

• B32B2457/10

  Batteries · CPC title

• H01M4/0404 Primary

  by coating on electrode collectors · CPC title

• B32B21/06

  of paper or cardboard · CPC title