Binder composition for non-aqueous secondary battery electrode, slurry composition for non-aqueous secondary battery positive electrode, positive electrode for non-aqueous secondary battery, and non-aqueous secondary battery

Patent metadata

Field	Value
Publication number	US-12100840-B2
Application number	US-202017594417-A
Country	US
Kind code	B2
Filing date	Apr 17, 2020
Priority date	Apr 18, 2019
Publication date	Sep 24, 2024
Grant date	Sep 24, 2024

Abstract

A binder composition for a non-aqueous secondary battery electrode contains a polymer A. The polymer A includes a nitrile group-containing monomer unit in a proportion of not less than 80.0 mass % and not more than 99.9 mass %, has a weight-average molecular weight (Mw) of not less than 700,000 and not more than 2,000,000, and has a molecular weight distribution (Mw/Mn) of less than 3.0.

First claim

The invention claimed is:

1. A binder composition for a non-aqueous secondary battery electrode comprising a polymer A, wherein
the polymer A includes a nitrile group-containing monomer unit in a proportion of not less than 80.0 mass % and not more than 99.9 mass %,
the polymer A has a weight-average molecular weight (Mw) of not less than 700,000 and not more than 2,000,000,
the polymer A has a molecular weight distribution (Mw/Mn) of less than 3.0,
the polymer A further includes either one or both of a carboxy group-containing monomer unit and a (meth)acrylic acid ester monomer unit, and
a proportional content of other monomer units in the polymer A is 0 mass %.

2. The binder composition for a non-aqueous secondary battery electrode according to claim 1 , wherein
the polymer A has a degree of swelling in electrolyte solution of not less than 120 mass % and not more than 250 mass %,
the degree of swelling in electrolyte solution being calculated by (W1/W0)×100 using mass W0 of a test specimen produced by drying an N-methyl-2-pyrrolidone dispersion of the polymer A under conditions of 2 hours at a temperature of 120° C. and mass W1 of the test specimen after 72 hours of immersion in electrolyte solution at a temperature of 60° C., and
the electrolyte solution being a solution in which LiPF 6 is dissolved in a concentration of 1.0 mol/L in a mixed solvent of ethylene carbonate and ethyl methyl carbonate having a volume mixing ratio of ethylene carbonate/ethyl methyl carbonate=3/7.

3. A slurry composition for a non-aqueous secondary battery positive electrode comprising: a positive electrode active material; a conductive material; and the binder composition for a non-aqueous secondary battery electrode according to claim 1 .

4. A positive electrode for a non-aqueous secondary battery comprising a positive electrode mixed material layer formed using the slurry composition for a non-aqueous secondary battery positive electrode according to claim 3 .

5. A non-aqueous secondary battery comprising a positive electrode, a negative electrode, a separator, and an electrolyte solution, wherein
the positive electrode is the positive electrode for a non-aqueous secondary battery according to claim 4 .

Assignees

• Zeon Corp

Inventors

• Murase Tomoya
• Asano Junichi
• Bando Fumiaki

Classifications

• H01M2300/0051

  Carbonates · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• H01M10/0569

  characterised by the solvents · CPC title

• H01M4/0416

  involving impregnation with a solution, dispersion, paste or dry powder (H01M4/0438 takes precedence) · CPC title

• H01M2300/0025

  Organic electrolyte · CPC title