Patent ID: 8026007

Claim:
A polymer electrolyte composition comprising: (1) a crosslinked material of a polyether binary copolymer which has a main chain consisting of repeating units of the formula (i) and crosslinking units of the formula (ii) and which has a weight-average molecular weight of 10 4 to 10 7 , wherein R 1 is an ethylenically unsaturated group having an ester linkage, (2) an electrolyte solution comprising an aprotic organic solvent, (3) an additive, as an optical ingredient, which comprises an ether compound having an ethylene oxide unit, and (4) an electrolyte salt compound comprising a lithium salt compound, wherein the amount of the electrolyte solution is within the range of 100 to 10,000 parts by weight, based on 100 parts by weight of the polyether binary copolymer.