Negative electrode and method for producing negative electrode, and electrode binding agent

Patent metadata

Field	Value
Publication number	US-12132201-B2
Application number	US-201917263339-A
Country	US
Kind code	B2
Filing date	Jul 10, 2019
Priority date	Aug 10, 2018
Publication date	Oct 29, 2024
Grant date	Oct 29, 2024

Abstract

A negative electrode using a binding agent excellent in binding property, the negative electrode being capable of using water as an alternative solvent to an organic solvent during production of the negative electrode. A negative electrode including: a compound obtained through condensation of polyacrylic acid and a polyaminobenzene derivative represented by general formula (1) below and/or a self-condensation product of the polyaminobenzene derivative; a cellulose derivative; and a negative electrode active material.

First claim

The invention claimed is:

1. A method for producing a negative electrode, the negative electrode comprising:
a compound obtained through condensation of polyacrylic acid and a polyaminobenzene derivative represented by formula (1) below and/or a self-condensation product of the polyaminobenzene derivative;
a cellulose derivative; and
a negative electrode active material,

wherein, in formula (1), R is each independently selected from alkyl optionally substituted with a substituent group, alkoxy, halogen, OH, SH, NO 2 , CN, CO 2 H, SO 3 H, or CONH 2 , and
m is an integer from 2 to 6, n is an integer from 0 to 4, and m+n≤6; and
wherein the compound contains a six-membered cyclic imide structure,
the method for producing the negative electrode comprising the steps of:
a) preparing a negative-electrode-active-material-layer forming composition containing a precursor of the compound obtained through condensation of the polyacrylic acid and the polyaminobenzene derivative and/or the self-condensation product of the polyaminobenzene derivative, the cellulose derivative, the negative electrode active material, and water, or a negative-electrode-active-material-layer forming composition containing the polyacrylic acid, the polyaminobenzene derivative and/or the self-condensation product of the polyaminobenzene derivative, the cellulose derivative, the negative electrode active material, and water;
b) applying the negative-electrode-active-material-layer forming composition on a current collector to produce a negative electrode precursor; and
c) heating the negative electrode precursor to cause condensation reaction between the polyacrylic acid and the polyaminobenzene derivative and/or the self-condensation product of the polyaminobenzene derivative to proceed,
wherein in the step c), light having a wavelength of 4 to 8 μm is applied to the negative electrode precursor.

2. The method for producing the negative electrode according to claim 1 , wherein
a mole ratio between an acrylic acid monomer unit forming the polyacrylic acid and the polyaminobenzene derivative is in a range of 2:1 to 50:1.

3. The method for producing the negative electrode according to claim 1 , wherein
a weight-average molecular weight of the polyacrylic acid is in a range of 400000 to 2000000.

4. The method for producing the negative electrode according to claim 1 , wherein
the negative electrode active material is an Si-containing negative electrode active material.

5. The method for producing the negative electrode according to claim 1 , wherein
the step c) is a step of using an apparatus including a roll unwinding unit configured to send out a negative electrode precursor in a roll shape, a roll winding unit by which a negative electrode is wound in a roll shape, and an irradiation unit disposed between the roll unwinding unit and the roll winding unit and configured to apply light having a wavelength of 4 to 8 μm.

6. The method for producing the negative electrode according to claim 1 , wherein
with respect to the polyaminobenzene derivative in the self-condensation product of the polyaminobenzene derivative, in the general formula (1), R is each independently selected from CO 2 H or SO 3 H, m is an integer from 2 to 5, n is an integer from 1 to 4, and m+n≤6.

Assignees

• Toyota Jidoshokki Kk

Inventors

• Kondo Takeshi
• Abe Tomokuni
• Oyaizu Keigo
• Tasaki Tomoyuki
• Fujisawa Hiroki

Classifications

• H01M2004/027

  Negative electrodes · CPC title

• H01M4/622 Primary

  being polymers · CPC title

• H01M4/366

  as layered products · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M4/386 Primary

  Silicon or alloys based on silicon · CPC title