Positive electrode active material for nonaqueous electrolyte secondary battery

Patent metadata

Field	Value
Publication number	US-11380892-B2
Application number	US-202016808525-A
Country	US
Kind code	B2
Filing date	Mar 4, 2020
Priority date	Mar 31, 2016
Publication date	Jul 5, 2022
Grant date	Jul 5, 2022

Abstract

A positive electrode active material for a nonaqueous electrolyte secondary battery includes particles of a lithium-transition metal composite oxide that contains nickel in the composition thereof and has a layered structure. The particles have an average particle size D SEM based on electron microscopic observation in a range of 1 μm to 7 μm in which a ratio D 50 /D SEM of a 50% particle size D 50 in volume-based cumulative particle size distribution to the average particle size based on electron microscopic observation is in a range of 1 to 4, and a ratio D 90 /D 10 of a 90% particle size D 90 to a 10% particle size D 10 in volume-based cumulative particle size distribution is 4 or less.

First claim

What is claimed is:

1. A positive electrode active material for a nonaqueous electrolyte secondary battery, comprising particles of a lithium-transition metal composite oxide that contains nickel in the composition thereof and has a layered structure, the particles having an average particle size D SEM based on electron microscopic observation in a range of 1 μm to 7 μm, wherein
a ratio D 50 /D SEM of a 50% particle size D 50 in volume-based cumulative particle size distribution to the average particle size based on electron microscopic observation is in a range of 1 to 4, and
a ratio D 90 /D 10 of a 90% particle size D 90 to a 10% particle size D 10 in volume-based cumulative particle size distribution is 4 or less; and wherein
the D SEM is to be determined as follows: observing an image at a magnification of 1,000 to 10,000 using a scanning electron microscope (SEM), selecting 100 particles having recognizable outlines, calculating the equivalent spherical diameters of the selected particles using an image processing software, and determining the arithmetic average of the obtained equivalent spherical diameters as D SEM .

2. The positive electrode active material according to claim 1 , wherein the ratio D 50 /D SEM of the D 50 to the D SEM is 1 to 3.

3. The positive electrode active material according to claim 1 , wherein the lithium-transition metal composite oxide has 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, 0.3≤x≤0.95, 0≤y≤50.4, 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.

4. The positive electrode active material according to claim 3 , wherein 0.3≤x<0.8, and the ratio D 50 /D SEM of the D 50 to the D SEM is in a range of 1 to 2.

5. The positive electrode active material according to claim 3 , wherein 0.3≤x<0.6, and a disorder of nickel element in the lithium-transition metal composite oxide particles determined by X-ray diffractometry is 1.5% or less.

6. The positive electrode active material according to claim 3 , wherein 0.3≤x<0.6, and the ratio D 90 /D 10 of the D 90 to the D 10 is 3 or less.

7. The positive electrode active material according to claim 3 , wherein 0.3≤x<0.6, and the ratio D 90 /D 10 of the D 90 to the D 10 is 2.5 or less.

8. The positive electrode active material according to claim 3 , wherein 0.3≤x<0.6, and the D 50 is in a range of 1 μm to 5.5 μm.

9. The positive electrode active material according to claim 3 , wherein 0.3≤x<0.6, and the D 50 is in a range of 1 μm to 3 μm.

10. The positive electrode active material according to claim 3 , wherein, when 0.3:5≤x<0.6, 1.1<p<1.2.

11. The positive electrode active material according to claim 3 , wherein 0.6≤x<0.8, and the disorder of elemental nickel in the lithium-transition metal composite oxide particles determined by X-ray diffractometry is 2.0% or less.

12. The positive electrode active material according to claim 3 , wherein 0.6≤x<0.8, and the ratio D 90 /D 10 of the D 90 to the D 10 is 2.3 or less.

13. The positive electrode active material according to claim 3 , wherein 0.6≤x<0.8, and the D 50 is in a range of 1 μm to 5.5 μm.

14. The positive electrode active material according to claim 3 , wherein 0.8≤x≤0.95, and the disorder of elemental nickel determined by X-ray diffractometry is 4.0% or less.

15. The positive electrode active material according to claim 3 , wherein 0.8≤x≤0.95, and the ratio D 90 /D 10 of the D 90 to the D 10 is 3 or less.

16. The positive electrode active material according to claim 3 , wherein 0.8≤x≤0.95, and the D 50 is in a range of 1 μm to 5.5 μm.

17. An electrode for a nonaqueous electrolyte secondary battery, comprising:
a current collector; and
a positive electrode active material layer that is disposed on the current collector and contains the positive electrode active material according to claim 1 .

18. A nonaqueous electrolyte secondary battery comprising the electrode according to claim 17 .

19. The positive electrode active material according to claim 1 , wherein the lithium-transition metal composite oxide has a composition in which a ratio of nickel to a total number of metals other than lithium is 0.3 to 0.95.

Assignees

• Honda Motor Co Ltd
• Nichia Corp

Inventors

• Ogawa Atsushi
• Kawamura Soshi
• Sukigara Toru
• Maeyama Hiroto
• Kobayashi Kenichi

Classifications

• 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

• 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

• C01P2006/40

  Electric properties · CPC title

• H01M2220/20

  Batteries in motive systems, e.g. vehicle, ship, plane · CPC title