Method of producing positive electrode active material for nonaqueous electrolyte secondary battery

Patent metadata

Field	Value
Publication number	US-10224547-B2
Application number	US-201715474584-A
Country	US
Kind code	B2
Filing date	Mar 30, 2017
Priority date	Mar 31, 2016
Publication date	Mar 5, 2019
Grant date	Mar 5, 2019

Abstract

A method of producing a positive electrode active material for a nonaqueous electrolyte secondary battery, the method includes preparing nickel-containing composite oxide particles having a ratio 1D90/1D10 of a 90% particle size 1D90 to a 10% particle size 1D10 in volume-based cumulative particle size distribution of 3 or less; obtaining a raw material mixture containing the composite oxide particles and a lithium compound and having a ratio of a total number of moles of lithium to a total number of moles of metal elements contained in the composite oxide in a range of 1 to 1.3; subjecting the raw material mixture to a heat treatment to obtain a heat-treated material; subjecting the heat-treated material to a dry-dispersion treatment to obtain a first dispersion; and bringing the first dispersion into contact with a liquid medium to obtain a second dispersion.

First claim

What is claimed is:

1. A method of producing a positive electrode active material for a nonaqueous electrolyte secondary battery, comprising:
preparing a raw material mixture containing nickel-containing composite oxide particles and a lithium compound, wherein said nickel-containing composite oxide particles have a ratio 1 D 90 / 1 D 10 of a 90% particle size 1 D 90 to a 10% particle size 1 D 10 in volume-based cumulative particle size distribution of 3 or less, and wherein said raw material mixture has a ratio of a total number of moles of lithium to a total number of moles of metal elements contained in the composite oxide in a range of 1 to 1.3;
subjecting the raw material mixture to a heat treatment to obtain a heat-treated material;
dissociating sintered primary particles from the heat-treated material to obtain a first dispersion; and
bringing the first dispersion into contact with a liquid medium to obtain a second dispersion,
wherein the positive electrode active material includes lithium-transition metal composite oxide particles having a ratio 2 D 50 / 2 D SEM of a 50% particle size 2 D 50 in volume-based cumulative particle size distribution to an average particle size 2 D SEM based on electron microscopic observation in a range of 1 to 4, and
wherein the lithium-transition metal composite oxide particles have a composition represented by the following formula (1):
Li p Ni x Co y M 1 z O 2+α   (1)

wherein p, x, y, z, and α satisfy 1.0≤p≤1.3, 0.6≤x<0.95, 0≤y≤0.4, 0≤z≤0.5, x+y+z=1, and −0.1≤α≤0.1, and M 1 represents at least one of Mn and Al.

2. The method according to claim 1 , wherein p in formula (1) satisfies 1.0≤p≤1.1.

3. The method according to claim 1 , wherein the lithium-transition metal composite oxide particles have a ratio 2 D 90 / 2 D 10 of a 90% particle size 2 D 90 to a 10% particle size 2 D 10 in volume-based cumulative particle size distribution of 4 or less.

4. The method according to claim 2 , wherein the lithium-transition metal composite oxide particles have a ratio 2 D 90 / 2 D 10 of a 90% particle size 2 D 90 to a 10% particle size 2 D 10 in volume-based cumulative particle size distribution of 4 or less.

5. The method according to claim 1 , wherein the heat treatment of the raw material mixture includes heat-treating at a first temperature and heat-treating at a second temperature higher than the first temperature.

6. The method according to claim 2 , wherein the heat treatment of the raw material mixture includes heat-treating at a first temperature and heat-treating at a second temperature higher than the first temperature.

7. The method according to claim 3 , wherein the heat treatment of the raw material mixture includes heat-treating at a first temperature and heat-treating at a second temperature higher than the first temperature.

8. The method according to claim 4 , wherein the heat treatment of the raw material mixture includes heat-treating at a first temperature and heat-treating at a second temperature higher than the first temperature.

9. The method according to claim 5 , wherein the heat treatment of the raw material mixture further includes, after heat-treating at the second temperature, heat-treating at a third temperature lower than the second temperature.

10. The method according to claim 6 , wherein the heat treatment of the raw material mixture further includes, after heat-treating at the second temperature, heat-treating at a third temperature lower than the second temperature.

11. The method according to claim 7 , wherein the heat treatment of the raw material mixture further includes, after heat-treating at the second temperature, heat-treating at a third temperature lower than the second temperature.

12. The method according to claim 8 , wherein the heat treatment of the raw material mixture further includes, after heat-treating at the second temperature, heat-treating at a third temperature lower than the second temperature.

13. The method according to claim 1 , wherein the heat treatment of the raw material mixture is performed in an oxygen-containing atmosphere.

14. The method according to claim 1 , wherein, in the step of bringing the first dispersion into contact with a liquid medium, the mass ratio of the liquid medium to the first dispersion in a range of 2 mass % to 20 mass %.

15. The method according to claim 1 , wherein the lithium-transition metal composite oxide particles have a ratio 2 D 90 / 2 D 10 of the 90% particle size 2 D 90 to the 10% particle size 2 D 10 in volume-based cumulative particle size distribution of 4 or less.

16. The method according to claim 1 , wherein the ratio 2 D 50 / 2 D SEM of the 2 D 50 to the 2 D SEM is in a range of 1 to 3.

17. The method according to claim 1 , wherein before the first step of preparing the raw material mixture, the nickel-containing composite oxide particles are made by heating a composite hydroxide containing a metal.

Assignees

• Nichia Corp

Inventors

• Kobayashi Kenichi

Classifications

• C01P2004/51

  Particles with a specific particle size distribution · CPC title

• H01M4/505

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

• C01G53/50

  of the type (MnO2)n-, e.g. Li(NixMn1-x)O2 or Li(MyNixMn1-x-y)O2 · CPC title

• H01M4/525 Primary

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title

• C01P2004/03

  obtained by SEM · CPC title