Method for forming positive electrode active material

Patent metadata

Field	Value
Publication number	US-12580194-B2
Application number	US-202017441808-A
Country	US
Kind code	B2
Filing date	Mar 23, 2020
Priority date	Apr 5, 2019
Publication date	Mar 17, 2026
Grant date	Mar 17, 2026

Abstract

A method for forming a positive electrode active material of a lithium ion secondary battery is provided. The method for forming a positive electrode active material includes a first step of placing a first container in which a mixture of a lithium oxide, a fluoride, and a magnesium compound are put, in a heating furnace, a second step of providing an atmosphere including oxygen in an inside of the heating furnace, and a third step of heating the inside of the heating furnace. The third step is performed after the first step and the second step are performed. Preferably, an atmosphere including oxygen is provided in the heating furnace before the inside of the heating furnace is heated. More preferably, the fluoride is lithium fluoride and the magnesium compound is magnesium fluoride.

First claim

The invention claimed is:

1 . A method for forming a positive electrode active material, comprising:
mixing and grinding lithium fluoride and magnesium fluoride to form a first mixture by a wet process; mixing the first mixture and a lithium cobalt oxide to form a second mixture by a dry process; placing a container in a heating furnace, wherein the container contains the second mixture; providing an atmosphere comprising oxygen to an inside of the heating furnace; and heating the container inside of the heating furnace in the atmosphere comprising oxygen, wherein the container defines an opening, and a lid is positioned over the opening, and wherein an atmosphere in a space enclosed by the container and the lid comprises fluoride.

2 . A method for forming a positive electrode active material, comprising:
mixing and grinding lithium fluoride and magnesium fluoride to form a first mixture by a wet process; mixing the first mixture and a lithium cobalt oxide to form a second mixture by a dry process; placing a container in a heating furnace, wherein the container contains the second mixture; evacuating air from an inside of the heating furnace and then introducing an oxygen gas; and heating the container inside of the heating furnace in the oxygen gas, wherein the container defines an opening, and a lid is positioned over the opening, and wherein an atmosphere in a space enclosed by the container and the lid comprises fluoride.

3 . The method for forming the positive electrode active material according to claim 1 , wherein the inside of the heating furnace is heated at a temperature higher than or equal to 735° C. and lower than or equal to 1000° C.

4 . The method for forming the positive electrode active material according to claim 2 , wherein the inside of the heating furnace is heated at a temperature higher than or equal to 735° C. and lower than or equal to 1000° C.

Assignees

• Semiconductor Energy Lab

Inventors

• Momma Yohei
• Ochiai Teruaki
• Mikami Mayumi
• Saito Jo
• Takahashi Masahiro

Classifications

• H01M2004/028

  Positive electrodes · CPC title

• H01M4/483

  for non-aqueous cells (H01M4/485 takes precedence) · CPC title

• H01M4/364

  as mixtures · CPC title

• H01M4/0471

  involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title