Binder for lithium cell

A binder for a lithium cell, comprising a polymer having

• (i) an acrylic acid monomer unit, and
• (ii) 1 to 2 kinds of monomer units other than acrylic acid derived from a compound represented by the following general formula (I) or general formula (II), as constituents, and
• cross-linked by a cross-linking agent which is a compounds represented by the following general formulae [4];
• wherein R1 represents hydrogen atom or a methyl group, and provided that in the case where R2 is hydrogen atom, R1 represents a methyl group;
• R2 represents hydrogen atom, an alkyl group having 1 to 20 carbon atoms;
• an alkyl group having 1 to 20 carbon atoms, which is substituted with fluorine atom, a hydroxyl group or a cyano group;
• an aryl group having 6 to 10 carbon atoms;
• an arylalkyl group having 7 to 13 carbon atoms;
• an alkoxyalkyl group having 2 to 9 carbon atoms;
• an alkoxyalkoxyalkyl group having 3 to 9 carbon atoms;
• an aryloxyalkyl group having 7 to 13 carbon atoms;
• a morpholinoalkyl group having 5 to 7 carbon atoms;
• a trialkylsilyl group having 3 to 9 carbon atoms;
• an alicyclic hydrocarbon group having 6 to 10 carbon atoms, which has oxygen or does not have oxygen;
• a dialkylaminoalkyl group having 3 to 9 carbon atoms;
• a hexahydrophthalimide-N-alkyl group having 9 to 15 carbon atoms;
• the group shown by the following general formula (IV)
• wherein R3 represents an alkylene group having 1 to 6 carbon atoms, which has a hydroxyl group as a substituent or does not have a substituent;
• R4 represents hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a phenyl group;
• “v” represents an integer of 2 to 20;
• or the group shown by the following general formula (V)
• wherein R5 to R7 each independently represent an alkyl group having 1 to 3 carbon atoms;
• R8 represents an alkylene group having 1 to 3 carbon atoms,
• wherein R11 represents hydrogen atom or a methyl group;
• R12 represents hydrogen atom, or alkyl group having 1 to 6 carbon atoms;
• R13 represents hydrogen atom, an alkyl group having 1 to 6 carbon atoms;
• a dialkylaminoalkyl group having 3 to 9 carbon atoms;
• or a hydroxyalkyl group having 1 to 6 carbon atoms,
• wherein R3 4 to R3 7 each independently represent an alkylene group having 1 to 6 carbon atoms;
• 1 represents an integer of 1 to 6;
• m represents an integer of 0 to 6;
• v1 and v2 each independently represent an integer of 0 or 1.