Graphene oxide, positive electrode for nonaqueous secondary battery using graphene oxide, method of manufacturing positive electrode for nonaqueous secondary battery, nonaqueous secondary battery, and electronic device

Patent metadata

Field	Value
Publication number	US-2020144622-A1
Application number	US-201916715732-A
Country	US
Kind code	A1
Filing date	Dec 16, 2019
Priority date	Apr 10, 2012
Publication date	May 7, 2020
Grant date	—

Abstract

A graphene oxide used as a raw material of a conductive additive for forming an active material layer with high electron conductivity with a small amount of a conductive additive is provided. A positive electrode for a nonaqueous secondary battery using the graphene oxide as a conductive additive is provided. The graphene oxide is used as a raw material of a conductive additive in a positive electrode for a nonaqueous secondary battery and, in the graphene oxide, the atomic ratio of oxygen to carbon is greater than or equal to 0.405.

First claim

1 . (canceled)

2 . A method for manufacturing a positive electrode, comprising the steps of:
adding a plurality of active material particles to a dispersion medium to obtain a first mixture; kneading the first mixture to obtain a second mixture; and adding a binder to the second mixture, wherein the dispersion medium comprises a carbon material, and wherein the binder is capable of adhering the plurality of active material particles and the carbon material.

3 . The method for manufacturing a positive electrode, according to claim 2 , further comprising the steps of:
applying the second mixture onto a positive electrode current collector; and evaporating the dispersion medium in the second mixture after applying the second mixture.

4 . The method for manufacturing a positive electrode, according to claim 2 , wherein the binder comprises any one of polvinyliden fluoride, polyimide, polytetrafluoroethylene, polyvinyl chloride, ethylene-propylene-diene polymer, styrene-butadiene rubber, acrylonitrile-butadiene rubber, fluorine rubber, polyvinyl acetate, polymethyl methacrylate, polyethylene and nitrocellulose.

5 . A method for manufacturing a positive electrode, comprising the steps of:
adding a plurality of active material particles and a binder to a dispersion medium to obtain a first mixture; and mixing the first mixture to obtain a second mixture, wherein the dispersion medium comprises a carbon material, and wherein the binder is capable of adhering the plurality of active material particles and the carbon material.

6 . The method for manufacturing a positive electrode, according to claim 5 , further comprising the steps of:
applying the second mixture onto a positive electrode current collector; and evaporating the dispersion medium in the second mixture after applying the second mixture.

7 . The method for manufacturing a positive electrode, according to claim 5 , wherein the binder comprises any one of polvinyliden fluoride, polyimide, polytetrafluoroethylene, polyvinyl chloride, ethylene-propylene-diene polymer, styrene-butadiene rubber, acrylonitrile-butadiene rubber, fluorine rubber, polyvinyl acetate, polymethyl methacrylate, polyethylene and nitrocellulose.

8 . A method for manufacturing an electrode, comprising the steps of:
kneading a first mixture comprising an active material particle, a piece of graphene oxide and a first solvent to obtain a second mixture; adding a second solvent to the second mixture to obtain a third mixture; and applying the third mixture to make an active material layer.

9 . The method for manufacturing an electrode, according to claim 8 , further comprising the step of:
adding a binder to the second mixture.

10 . The method for manufacturing an electrode, according to claim 8 , wherein a primary particle size is less than or equal to 500 nm.

11 . The method for manufacturing an electrode, according to claim 8 , wherein the active material particle comprises a lithium-containing composite oxide.

12 . The method for manufacturing an electrode, according to claim 11 , wherein the lithium-containing composite oxide is any one of LiCoO 2 , NiCo-containing composite oxide, LiMPO 4 (where M is one or more of Fe, Mn, Co and Ni).

Assignees

• Semiconductor Energy Lab

Inventors

• Todoriki Hiroatsu
• Yukawa Mikio
• Saito Yumiko
• Yamakaji Masaki
• Yatabe Rika
• Ikenuma Tatsuya

Classifications

• H01M4/624

  Electric conductive fillers · CPC title

• H01M4/625 Primary

  Carbon or graphite · CPC title

• H01M10/052

  Li-accumulators · CPC title

• H01M4/366

  as layered products · CPC title

• H01M4/364

  as mixtures · CPC title