Positive electrode active material for lithium ion secondary battery and lithium ion secondary battery

Patent metadata

Field	Value
Publication number	US-12334549-B2
Application number	US-202017637914-A
Country	US
Kind code	B2
Filing date	Aug 28, 2020
Priority date	Aug 30, 2019
Publication date	Jun 17, 2025
Grant date	Jun 17, 2025

Abstract

A positive electrode active material for a lithium ion secondary battery, the positive electrode active material including a lithium-nickel composite oxide having a hexagonal layered structure and configured by particles including at least either single primary particles or secondary particles with a plurality of aggregated primary particles, wherein the particles of the positive electrode active material have a cross section having an area proportion of a crystal face having a maximum area in the particle of 80% or more when one crystal face is defined as a region having a crystal misorientation of 15° or less.

First claim

The invention claimed is:

1. A positive electrode active material for a lithium ion secondary battery, the positive electrode active material comprising a lithium-nickel composite oxide having a hexagonal layered structure and configured by particles including at least either single primary particles or secondary particles with a plurality of aggregated primary particles,
wherein metal elements constituting the lithium-nickel composite oxide include lithium (Li), nickel (Ni), and optionally at least one element M (M) selected from the group consisting of Co, Mn, Al, V, Mg, Mo, Ca, Cr, Zr, Ti, Nb, Na, K, W, Fe, Zn, B, Si, P, and Ta,
a mole number ratio of the metal elements is represented as Li:Ni:M=a:b:c (provided that, 0.95≤a≤1.10, 0.30≤b≤1.00, 0.00≤c≤0.70, and b+c=1), and
the particles included in the positive electrode active material have a cross section having an area proportion of a crystal face having a maximum area to the cross section of 80% or more when one crystal face is defined as a region having a crystal misorientation of 15° or less with respect to an orientation of the cross section measured by Electron Backscatter Diffraction method.

2. The positive electrode active material for a lithium ion secondary battery according to claim 1 , wherein a number proportion of the single primary particles to all of the particles is 30% or more, the number proportion being determined under scanning electron microscope (SEM) observation of a particle cross section of the lithium-nickel composite oxide.

3. The positive electrode active material for a lithium ion secondary battery according to claim 1 , wherein a ratio of a (003) diffraction peak intensity I (003) to a (104) diffraction peak intensity I (104) (I (003) /I (104) ) is 2.0 or more, the (003) diffraction peak intensity and the (104) diffraction peak intensity determined from X-ray diffraction measured using a flat plate sample holder of a Bragg Brentano optical system using a Cu-kα ray as an X-ray source.

4. The positive electrode active material for a lithium ion secondary battery according to claim 1 , wherein the positive electrode active material has a volume-based median diameter (D50) of 10 μm or less, and the lithium-nickel composite oxide has an average primary particle size of 0.3 μm or more.

5. The positive electrode active material for a lithium ion secondary battery according to claim 1 , wherein the positive electrode active material has a specific surface area of 1.0 m 2 /g or more and 5.0 m 2 /g or less, the specific surface area determined with a nitrogen adsorption method.

6. A lithium ion secondary battery comprising: a positive electrode; a negative electrode; and a non-aqueous electrolyte, the positive electrode containing the positive electrode active material for a lithium ion secondary battery according to claim 1 .

7. The positive electrode active material for a lithium ion secondary battery according to claim 1 , wherein a number proportion of the single primary particles to all of the particles is 50% or more, the number proportion being determined under scanning electron microscope (SEM) observation of a particle cross section of the lithium-nickel composite oxide.

8. The positive electrode active material for a lithium ion secondary battery according to claim 1 , wherein a number proportion of the single primary particles to all of the particles is 70% or more, the number proportion being determined under scanning electron microscope (SEM) observation of a particle cross section of the lithium-nickel composite oxide.

9. The positive electrode active material for a lithium ion secondary battery according to claim 1 , wherein the area proportion of the crystal face having the maximum area to the cross section is 90% or more.

Assignees

• Sumitomo Metal Mining Co

Inventors

• KANEDA Haruki
• Koshika Yuki

Classifications

• C01P2004/50

  Agglomerated particles · CPC title

• C01G53/42

  containing alkali metals, e.g. LiNiO2 · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title