| abstract |
A binder composition comprising a polymer dispersed inna liquid dispersion medium, wherein the polymer comprisesnstructural units represented by the following formula:n nwherein R 1 is hydrogen, C1-4 alkyl group, or halogen, R 2 is C1-20nalkyl group or C6-30 aryl group, R 3 and R 4 are hydrogen or methylngroup, provided that R 3 and R 4 are not simultaneously methyl group,nand n is an integer of 1 - 50. A lithium ion secondary batterynhaving an electrode made by using this binder compositionnexhibits excellent characteristics at repetition of ancharge-discharge cycle. |