Binder for lithium ion battery electrode, paste for lithium ion battery negative electrode, and method for producing lithium ion battery negative electrode
AssigneeToray Industries, Inc.
InventorsMasao Tomikawa, Tomoyuki Yuba, Natsuko Chayama
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Abstract
The present invention is directed to a binder for a lithium ion battery electrode, comprising a polyimide precursor having a tetracarboxylic acid residue and a diamine residue and/or a polyimide, the polyimide precursor having a residue of a tetracarboxylic dianhydride selected from those represented by the following general formulas (1) and (2) as the tetracarboxylic acid residue, and a residue of a diamine selected from those represented by the following general formulas (3) and (4) as the diamine residue, the content of the acid residue being from 0.90 to 0.95 moles based on 1 mole of the diamine residue.
Claims7
A lithium ion battery negative electrode, comprising a negative electrode active material and a polyimide containing a tetracarboxylic acid residue and a diamine residue,
- wherein the tetracarboxylic acid residue is a dianhydride residue of a tetracarboxylic dianhydride, said tetracarboxylic dianhydride represented by the following general formula (1) and/or said tetracarboxylic dianhydride represented by the following general formula (2),
- wherein the diamine residue is a residue of a diamine, said diamine represented by the following general formula (3) and/or said diamine represented by the following general formula (4):
- wherein Y represents a group selected from an amide group and an ether group;
- n is 0;
- m and o are 0;
- p, q and r are 0;
- and s is an integer of from 1 to 4,
- wherein the content of the tetracarboxylic acid residue is from 0.91 to 0.94 moles based on one mole of the diamine residue,
- wherein the number average polymerization degree of the polyimide before heat treatment is from 10 to 20,
- wherein z is a direct bond or a carbonyl group, and
- wherein an amino group is formed at an end of the polyimide.
Dependencies are inferred from the claim text.