Electrode, manufacturing method thereof, storage battery, and electronic device

Patent metadata

Field	Value
Publication number	US-2021143419-A1
Application number	US-202117152830-A
Country	US
Kind code	A1
Filing date	Jan 20, 2021
Priority date	Aug 27, 2015
Publication date	May 13, 2021
Grant date	—

Abstract

As a positive electrode active material of a secondary battery, a lithium-manganese composite oxide containing lithium, manganese, and an element represented by M, and oxygen is used, and the lithium-manganese composite oxide is covered with reduced graphene oxide. An active material layer including the active material, graphene oxide, a conductive additive, and a binder is formed and soaked in alcohol, and then heat treatment is performed, whereby an electrode with reduced graphene oxide is fabricated.

First claim

What is claimed is:

1 . A method for manufacturing an electrode, comprising:
forming an active material layer over a current collector, the active material a comprising a particle and a piece of graphene oxide covering the particle; impregnating the active material layer with alcohol; and performing heat treatment on the active material layer after impregnating the active material layer, wherein the particle comprises an inner region and a surficial region after the heat treatment, wherein the inner region comprises a crystal having a layered rock-salt crystal structure, wherein the surficial region comprises a crystal having a spinel crystal structure, and wherein the surficial region is in contact with the piece of graphene oxide being reduced.

2 . The method for manufacturing an electrode, according to claim 1 , wherein the particle has a cleavage plane.

3 . The method for manufacturing an electrode, according to claim 1 ,
wherein a composition of the particle is represented by Li a Mn b M c O d , and wherein the element M is any one of chromium, cobalt, aluminum, nickel, iron, magnesium, molybdenum, zinc, indium, gallium, copper, titanium, niobium, silicon and phosphorus.

4 . The method for manufacturing an electrode, according to claim 1 , wherein the element M is nickel.

5 . The method for manufacturing an electrode, according to claim 1 , wherein the alcohol is any one of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutyl alcohol and tert-butyl alcohol.

6 . The method for manufacturing an electrode, according to claim 1 , further comprising:
reducing the graphene oxide by a reducing agent before impregnating the particle.

7 . A method for manufacturing an active material, comprising:
covering an active material particle with a piece of graphene oxide; impregnating the active material particle covered with the piece of graphene oxide; performing heat treatment on the active material particle after the impregnating step, wherein the active material particle comprises an inner region and a surficial region after the heat treatment, wherein the inner region comprises a crystal having a layered rock-salt crystal structure, wherein the surficial region comprises a crystal having a spinel crystal structure, and wherein the surficial region is in contact with the piece of graphene oxide being reduced.

8 . The method for manufacturing an active material, according to claim 7 , wherein the active material particle has a cleavage plane.

9 . The method for manufacturing an active material, according to claim 7 ,
wherein a composition of the active material particle is represented by Li a Mn b M c O d , and wherein the element M is any one of chromium, cobalt, aluminum, nickel, iron, magnesium, molybdenum, zinc, indium, gallium, copper, titanium, niobium, silicon and phosphorus.

10 . The method for manufacturing an active material, according to claim 7 , wherein the alcohol is any one of methanol, ethanol. 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutyl alcohol and tert-butyl alcohol.

11. The method for manufacturing an active material, according to claim 7 , further comprising:
reducing the graphene oxide by a reducing agent before impregnating the active material particle.

Assignees

• Semiconductor Energy Lab

Inventors

• Ikenuma Tatsuya

Classifications

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M2220/30

  Batteries in portable systems, e.g. mobile phone, laptop · CPC title

• Y02P70/50

  Manufacturing or production processes characterised by the final manufactured product · CPC title

• H01M4/505 Primary

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title

• H01M4/131 Primary

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title