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

Patent metadata

Field	Value
Publication number	US-2017288222-A1
Application number	US-201715474584-A
Country	US
Kind code	A1
Filing date	Mar 30, 2017
Priority date	Mar 31, 2016
Publication date	Oct 5, 2017
Grant date	—

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 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; 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 nickel-containing composite oxide particles having 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; 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, 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.

Assignees

• Nichia Corp

Inventors

• Kobayashi Kenichi

Classifications

• C01P2006/40

  Electric properties · CPC title

• H01M4/505

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

• C01P2004/51

  Particles with a specific particle size distribution · CPC title

• C01P2004/03

  obtained by SEM · CPC title

• C01P2004/61

  Micrometer sized, i.e. from 1-100 micrometer · CPC title