Binder composition for secondary battery electrode-use, slurry composition for secondary battery electrode-use, electrode for secondary battery-use, and secondary battery

A binder composition for secondary battery electrode-use comprising:

• a copolymer;
• and
• a dispersion medium, wherein
• the copolymer includes at least 5 mass % and no greater than 80 mass % of a constitutional unit represented by formula (I) shown below
• where, in formula (I), R1 represents hydrogen or a monovalent organic group, R2, R3, and R4 each represent, independently of one another, hydrogen or a monovalent organic group, X represents a hydrocarbon chain, and A− represents a monovalent anion selected from the group consisting of a bis(trifluoromethanesulfonyl)imide anion, a bis(fluorosulfonyl)imide anion, a perfluoroalkanesulfonate anion, and a monoalkyl sulfate anion,
• the copolymer includes at least 5 mass % and no greater than 90 mass % of a constitutional unit represented by formula (II) shown below
• where, in formula (II), R5 represents hydrogen, a methyl group, or a halogen atom, and
• the copolymer includes no greater than 20 mass % of a constitutional unit represented by formula (III) shown below
• where, in formula (III), R6 represents hydrogen or a substituted or unsubstituted alkyl group, and R7 and R8 each represent, independently of one another, hydrogen or a group selected from the group consisting of a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, and a substituted or unsubstituted aryl group.