Negative electrode, battery, and method of producing negative electrode

Patent metadata

Field	Value
Publication number	US-11539048-B2
Application number	US-201916587629-A
Country	US
Kind code	B2
Filing date	Sep 30, 2019
Priority date	Oct 1, 2018
Publication date	Dec 27, 2022
Grant date	Dec 27, 2022

Abstract

A negative electrode includes at least a negative electrode composite material layer. The negative electrode composite material layer contains at least composite particles and a binder. Each composite particle includes a negative electrode active material particle and a film. The film covers at least part of a surface of the negative electrode active material particle. The film contains a layered silicate mineral. The binder includes nanofibers.

First claim

What is claimed is:

1. A negative electrode comprising at least:
a negative electrode composite material layer,
the negative electrode composite material layer containing at least composite particles and a binder,
each composite particle including a negative electrode active material particle and a film,
the film covering at least part of a surface of the negative electrode active material particle,
the film containing a layered silicate mineral containing an aluminosilicate,
the binder including oxidized cellulose nanofibers,
the layered silicate mineral is contained in an amount not lower than 0.5 parts by mass and not higher than 1.5 parts by mass relative to 100 parts by mass of the negative electrode active material particles, and
the binder is contained in an amount not lower than 1 part by mass and not higher than 2.5 parts by mass relative to 100 parts by mass of the negative electrode active material particles,
the oxidized cellulose nanofibers comprises cellulose molecular chains having carboxy groups, and
the carboxy groups form a composite with the layered silicate mineral.

2. The negative electrode according to claim 1 , wherein the film contains a montmorillonite.

3. The negative electrode according to claim 1 , wherein the negative electrode active material particle includes graphite.

4. A battery comprising at least:
the negative electrode according to claim 1 ;
a positive electrode; and
an electrolyte solution.

5. A method of producing a negative electrode, comprising at least:
preparing a composite particle by forming a film that covers at least part of a surface of a negative electrode active material particle; and
producing a negative electrode by forming a negative electrode composite material layer that contains at least a plurality of the composite particle and a binder,
the film containing a layered silicate mineral containing an aluminosilicate,
the binder including oxidized cellulose nanofibers,
the layered silicate mineral is contained in an amount not lower than 0.5 parts by mass and not higher than 1.5 parts by mass relative to 100 parts by mass of the negative electrode active material particles, and
the binder is contained in an amount not lower than 1 part by mass and not higher than 2.5 parts by mass relative to 100 parts by mass of the negative electrode active material particles,
the oxidized cellulose nanofibers comprises cellulose molecular chains having carboxy groups, and
the carboxy groups form a composite with the layered silicate mineral.

6. The negative electrode according to claim 1 , wherein the film contains a montmorillonite, and the montmorillonite is the only aluminosilicate in the film.

Assignees

• Toyota Motor Co Ltd

Inventors

• Oyama Yutaka
• Onodera Naoto

Classifications

• H01M4/667

  in the form of layers, e.g. coatings · CPC title

• H01M4/587

  for inserting or intercalating light metals · CPC title

• H01M4/621 Primary

  Binders · CPC title

• H01M4/622

  being polymers · CPC title

• H01M4/13 Primary

  Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof · CPC title