Nonaqueous electrolyte secondary battery

Patent metadata

Field	Value
Publication number	US-11024837-B2
Application number	US-201716321900-A
Country	US
Kind code	B2
Filing date	Jul 28, 2017
Priority date	Aug 9, 2016
Publication date	Jun 1, 2021
Grant date	Jun 1, 2021

Abstract

A nonaqueous electrolyte secondary battery according to an embodiment includes an electrode body, which is formed by winding a positive electrode and a negative electrode through a separator and then compressing into a flat shape, and a nonaqueous electrolyte. The positive electrode contains a lithium transition metal oxide which contains tungsten oxide adhering to the particle surfaces thereof. The negative electrode contains a negative electrode active material, which has particle surfaces coated with an amorphous carbon film, and at least one of polyacrylic acid and a salt thereof. The pressure acting in the thickness direction of the electrode body is 5×10−2 MPa or more.

First claim

The invention claimed is:

1. A nonaqueous electrolyte secondary battery comprising an electrode body, which is formed by laminating a positive electrode and a negative electrode through a separator, a nonaqueous electrolyte, and an outer package, which houses the electrode body and the nonaqueous electrolyte,
wherein the positive electrode contains a lithium transition metal oxide which contains tungsten oxide adhering to particle surfaces thereof;
the negative electrode contains a negative electrode active material, which includes graphite, which has an amorphous carbon film, and amorphous carbon particles and at least one of polyacrylic acid and a salt thereof;
wherein amorphous carbon of the amorphous carbon film and the amorphous carbon particles is present in an amount of 5% by mass to 30% by mass relative to the negative electrode active material; and
pressure acting in the thickness direction of the electrode body is 5×10 −2 MPa or more, wherein the pressure is applied in a thickness direction of the electrode body by a member which presses the outer package.

2. The nonaqueous electrolyte secondary battery according to claim 1 , wherein a ratio of coverage of at least one of polyacrylic acid and a salt thereof on particle surfaces of the amorphous carbon to a coverage of at least one of polyacrylic acid and a salt thereof on the surfaces of the graphite having the amorphous carbon film is 1.2 or more.

3. The nonaqueous electrolyte secondary battery according to claim 1 , wherein the lithium transition metal oxide contains at least one of tungsten (W) and zirconium (Zr).

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Takada Akihiko
• Urata Sho
• Tuduki Kouhei
• Niina Fumiharu
• Yanagida Katsunori

Classifications

• H01M10/0587

  of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators · CPC title

• H01M4/62

  Selection of inactive substances as ingredients for active masses, e.g. binders, fillers · CPC title

• H01M4/587

  for inserting or intercalating light metals · CPC title

• H01M4/133

  Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title

• H01M10/0525

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