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

Patent metadata

Field	Value
Publication number	US-12334550-B2
Application number	US-202017637925-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, 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 included in the positive electrode active material have a cross section having one or more crystal faces, and the one or more crystal faces in the particles have an average misorientation of 0.7° or less from a reference orientation of each of the one or more crystal faces.

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),
the particles included in the positive electrode active material have a cross section having one or more crystal faces, and the one or more crystal faces in the particles have an average misorientation of 0.7° or less from a reference orientation of each of the one or more crystal faces, wherein the average misorientation is determined by an electron backscatter diffraction EBSD) 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 average misorientation is 0.5° or less.

Assignees

• Sumitomo Metal Mining Co

Inventors

• KANEDA Haruki
• Koshika Yuki
• Koyama 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