Positive electrode active material for nonaqueous electrolyte secondary batteries, and nonaqueous electrolyte secondary battery

Patent metadata

Field	Value
Publication number	US-12283692-B2
Application number	US-202017763987-A
Country	US
Kind code	B2
Filing date	Sep 29, 2020
Priority date	Sep 30, 2019
Publication date	Apr 22, 2025
Grant date	Apr 22, 2025

Abstract

This positive electrode active material for nonaqueous electrolyte secondary batteries includes a lithium transition metal complex oxide that has a spinel structure and that is represented by general formula Li 1+α Ni 0.5-x Mn 1.5-y-z Ge y M x+z O 4 (in the formula, 0≤α<0.2, 0≤x<0.2, 0<y<0.45, and 0≤z<0.2 are satisfied, and M represents at least one element selected from the group consisting of Mg, Al, Sc, Ti, Cr, V, Fe, and Co). In a secondary particle of the lithium transition metal complex oxide, the mole number (Ge surf ) of Ge at the surface portion when the total number of moles of metal elements other than Li is defined as 2 is larger than the mole number (Ge bulk ) of Ge at the center portion when the total number of moles of metal elements other than Li is defined as 2.

First claim

The invention claimed is:

1. A positive electrode active material for a non-aqueous electrolyte secondary battery, the positive electrode active material including a lithium-transition metal composite oxide having a spinel structure and represented by the general formula Li 1+α Ni 0.5-x Mn 1.5-y-z Ge y M x+z O 4 , wherein 0≤α<0.2, 0≤x<0.2, 0<y<0.45, 0≤z<0.2, and M represents at least one or more elements selected from the group consisting of Mg, Al, Sc, Ti, Cr, V, Fe, and Co, wherein
when, on a cross section of a secondary particle of the lithium-transition metal composite oxide, a thickness portion from a center to a ⅓ radius is defined as a central portion, and a thickness portion from a surface to the ⅓ radius is defined to as a surface portion, in the secondary particle of the lithium-transition metal composite oxide, Ge surf is higher than Ge bulk , where Ge surf represents a number of moles of Ge based on a total number of moles of metal elements excluding Li being 2 in the surface portion, and Ge bulk represents a number of moles of Ge based on a total number of moles of metal elements excluding Li being 2 in the central portion, and
a ratio of the Ge surf to the Ge bulk (Ge surf /Ge bulk ) satisfies a relation of 1.5<Ge surf /Ge bulk <5.0.

2. The positive electrode active material for a non-aqueous electrolyte secondary battery according to claim 1 , wherein the Ge bulk satisfies 0.005<Ge bulk <0.45.

3. A non-aqueous electrolyte secondary battery, comprising:
a positive electrode including the positive electrode active material for a non-aqueous electrolyte secondary battery according to claim 1 ;
a negative electrode; and
an electrolyte.

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Kawada Hiroshi
• Murata Akiko
• Hibino Mitsuhiro

Classifications

• H01M10/0525

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

• C01G53/54

  of the type (Mn2O4)-, e.g. Li(NixMn2-x)O4 or Li(MyNixMn2-x-y)O4 · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• H01M4/505 Primary

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

• C01P2006/40

  Electric properties · CPC title