Nonaqueous electrolyte secondary battery

Patent metadata

Field	Value
Publication number	US-12009506-B2
Application number	US-202016930746-A
Country	US
Kind code	B2
Filing date	Jul 16, 2020
Priority date	Jul 18, 2019
Publication date	Jun 11, 2024
Grant date	Jun 11, 2024

Abstract

The present disclosure can bring excellent output characteristics to a nonaqueous electrolyte secondary battery that uses a cathode active material containing tungsten while desired durability is secured. The battery of the present disclosure includes a cathode, an anode, and a nonaqueous electrolyte. The cathode includes a cathode active material layer that contains a granular cathode active material. The cathode active material includes a core part that contains a lithium-transition metal composite oxide of a layered structure; a tungsten-concentrated layer that is formed over a surface of the core part and has a higher tungsten concentration than in the core part; and a lithium-tungsten compound particle that adheres to at least part of a surface of the tungsten-concentrated layer and contains tungsten and lithium. In the battery of the present disclosure, the tungsten-concentrated layer has an amorphous structure. This can bring excellent output characteristics while desired durability is secured.

First claim

What is claimed is:

1. A nonaqueous electrolyte secondary battery comprising a cathode, an anode, and a nonaqueous electrolyte,
the cathode including a cathode active material layer that contains a granular cathode active material;
the granular cathode active material including:
a core part that contains a lithium-transition metal composite oxide of a layered structure, a mean particle size of the core part is from 0.1 μm to 20 μm;
a tungsten-concentrated layer that is formed over a surface of the core part and has a higher tungsten concentration determined by a TEM-EDX analysis than the core part; and
a lithium-tungsten compound particle that adheres to at least part of a surface of the tungsten-concentrated layer and contains tungsten and lithium, the tungsten-concentrated layer is an amorphous structure, and the lithium-tungsten compound particle has a higher tungsten concentration than the tungsten-concentrated layer, and an atomic concentration of tungsten in the lithium-tungsten compound particle is 90 at % or more based on a total number of transition metal atoms.

2. The nonaqueous electrolyte secondary battery according to claim 1 , wherein an atomic concentration A of tungsten in the tungsten-concentrated layer is 1 at % or more and 3.6 at % or less.

3. The nonaqueous electrolyte secondary battery according to claim 1 , wherein an atomic concentration B of tungsten in the core part is 0.3 at % or less.

4. The nonaqueous electrolyte secondary battery according to claim 1 , wherein the core part comprises Li, Ni, Co, Mn, and O.

5. The nonaqueous electrolyte secondary battery according to claim 1 , wherein a mean particle size of the lithium-tungsten compound particle is from 5 nm to 500 nm.

Assignees

• Toyota Motor Co Ltd
• Sumitomo Metal Mining Co
• Toyota Jidosha Kk And

Inventors

• Yamamoto Yuji
• Procter Momoko
• Makimura Yoshinari
• Hayashi Tetsutaro
• Bong Willy Shun Kai

Classifications

• H01M4/131

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M10/0525

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

• H01M2004/027

  Negative electrodes · CPC title

• H01M4/485

  of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy (H01M4/505, H01M4/525 take precedence) · CPC title

• Y02P70/50

  Manufacturing or production processes characterised by the final manufactured product · CPC title