Positive electrode active material particle

Patent metadata

Field	Value
Publication number	US-11489151-B2
Application number	US-201816607381-A
Country	US
Kind code	B2
Filing date	May 1, 2018
Priority date	May 12, 2017
Publication date	Nov 1, 2022
Grant date	Nov 1, 2022

Abstract

A positive electrode active material particle with little deterioration is provided. A power storage device with little deterioration is provided. A highly safe power storage device is provided. The positive electrode active material particle includes a first crystal grain, a second crystal grain, and a crystal grain boundary positioned between the crystal grain and the second crystal grain; the first crystal grain and the second crystal grain include lithium, a transition metal, and oxygen; the crystal grain boundary includes magnesium and oxygen; and the positive electrode active material particle includes a region where the ratio of the atomic concentration of magnesium in the crystal grain boundary to the atomic concentration of the transition metal in first crystal grain and the second crystal grain is greater than or equal to 0.010 and less than or equal to 0.50.

First claim

The invention claimed is:

1. A lithium-ion secondary battery comprising:
a positive electrode active material particle including a crystal grain boundary and a plurality of crystal grains,
wherein the positive electrode active material particle comprises a region in which a ratio of a number of magnesium atoms in the crystal grain boundary or a periphery of the crystal grain boundary to a number of cobalt atoms in one of the plurality of the crystal grains is greater than or equal to 0.010 and less than or equal to 0.5.

2. The lithium-ion battery according to claim 1 , wherein the positive electrode active material particle comprises a region in which a ratio of a number of magnesium atoms in the crystal grain boundary or the periphery of the crystal grain boundary to a number of cobalt atoms in the one of the plurality of the crystal grains is greater than or equal to 0.03.

3. The lithium-ion secondary battery according to claim 1 ,
wherein, in EDX linear analysis for the one of the plurality of the crystal grains, magnesium is detected at a level of the lower detection limit, and
wherein, in EDX linear analysis for the crystal grain boundary or the periphery of the crystal grain boundary, magnesium is detected beyond the level of the lower detection limit.

4. The lithium-ion secondary battery according to claim 1 ,
wherein, in EDX linear analysis for the one of the plurality of the crystal grains, magnesium is detected at lower than 1 atomic %, and
wherein, in EDX linear analysis for the crystal grain boundary or the periphery of the crystal grain boundary, magnesium is detected beyond 1 atomic %.

5. The lithium-ion secondary battery according to claim 1 ,
wherein the number of magnesium atoms and the number of cobalt atoms is obtained with EDX linear analysis.

6. The lithium-ion battery according to claim 1 , further comprising a conductive additive,
wherein the conductive additive includes carbon fiber.

7. The lithium-ion battery according to claim 6 , wherein the carbon fiber includes carbon nanofiber or carbon nanotube.

8. The lithium-ion battery according to claim 6 , wherein the conductive additive further includes any one of carbon black, graphite particle, graphene, and fullerene.

9. The lithium-ion battery according to claim 1 , wherein the positive electrode active material particle comprises a region in which a ratio of a number of fluorine atoms in the crystal grain boundary or a periphery of the crystal grain boundary to a number of cobalt atoms in one of the plurality of the crystal grains is greater than or equal to 0.020 and less than or equal to 1.00.

10. A lithium-ion secondary battery comprising:
a positive electrode active material particle including a crystal grain boundary and a plurality of crystal grains,
wherein the positive electrode active material particle comprises a region in which a ratio of a number of magnesium atoms in the crystal grain boundary or a periphery of the crystal grain boundary to a number of transition metal atoms in one of the plurality of the crystal grains is greater than or equal to 0.010 and less than or equal to 0.5,
wherein the transition metal comprises cobalt, nickel and manganese, and
wherein the number of the transition metal atoms refers to the total number of atoms of each of cobalt, nickel, and manganese included in the one of the plurality of the crystal grains.

11. The lithium-ion battery according to claim 10 , wherein the positive electrode active material particle comprises a region in which a ratio of a number of magnesium atoms in the crystal grain boundary or the periphery of the crystal grain boundary to a number of transition metal atoms in the one of the plurality of the crystal grains is greater than or equal 0.03.

12. The lithium-ion secondary battery according to claim 10 ,
wherein, in EDX linear analysis for the one of the plurality of the crystal grains, magnesium is detected at a level of the lower detection limit, and
wherein, in EDX linear analysis for the crystal grain boundary or the periphery of the crystal grain boundary, magnesium is detected beyond the level of the lower detection limit.

13. The lithium-ion secondary battery according to claim 10 ,
wherein, in EDX linear analysis for the one of the plurality of the crystal grains, magnesium is detected at lower than 1 atomic %, and
wherein, in EDX linear analysis for the crystal grain boundary or the periphery of the crystal grain boundary, magnesium is detected beyond 1 atomic %.

14. The lithium-ion secondary battery according to claim 10 ,
wherein the number of magnesium atoms and the number of transition metal atoms is obtained with EDX linear analysis.

15. The lithium-ion battery according to claim 10 , further comprising a conductive additive,
wherein the conductive additive includes carbon fiber.

16. The lithium-ion battery according to claim 15 , wherein the carbon fiber includes carbon nanofiber or carbon nanotube.

17. The lithium-ion battery according to claim 15 , wherein the conductive additive further includes any one of carbon black, graphite particle, graphene, and fullerene.

Assignees

• Semiconductor Energy Lab

Inventors

• Takahashi Masahiro
• Ochiai Teruaki
• Momma Yohei
• TSURUTA Ayae

Classifications

• Y02E60/10

  Energy storage using batteries · CPC title

• C01G51/00

  Compounds of cobalt · CPC title

• H01M4/505

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

• H01M4/485 Primary

  of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy (H01M4/505, H01M4/525 take precedence) · CPC title

• H01M4/366

  as layered products · CPC title