Patent ID: 8318361

Claim:
A composition for a gel polymer electrolyte, the composition comprising: (i) a cyclic compound as a first crosslinking agent, the cyclic compound containing a cyclic group at the center thereof and having at least three double bonds at the end thereof; (ii) a linear or branched compound as a second crosslinking agent, the linear or branched compound containing an oxyalkylene group at the center thereof and having at least two (meth)acryl groups at the end thereof; (iii) an electrolyte solvent; (iv) an electrolyte salt; and (v) a polymerization initiator, wherein (i) the cyclic compound is a compound represented by Formula 1 or Formula 2 below or a mixture thereof: wherein R 1 is H or a methyl group; R 2 is a C1-C12 alkylene group; n is 0 or 1; and W is a vinyl group or (meth)acrylate group, wherein R 3 is H or a methyl group; R 4 is a C1-C12 alkylene group; n is 0 or 1; and W is a vinyl group or (meth)acrylate group; (ii) the linear or branched compound is a compound represented by Formula 3 below: wherein A is a C1-C12 alkylene group or C1-C12 haloalkylene group; a is an integer of 0 to 30; B is H or a methyl group; b is an integer of 2 to 6; X represents any one of wherein each of E 1 , E 2 , E 3 and E 4 independently represents H, a C1-C12 alkyl group, C1-C12 haloalkyl group or C1-C12 hydroxyalkyl group; and m is an integer of 0 to 30, and (v) the polymerization initiator is selected from the group consisting of benzoyl peroxide, acetyl peroxide, dilauryl peroxide, di-tert-butyl peroxide, cumyl hydroperoxide, hydrogen peroxide, 2,2-zaobis(2-cyanobutane), 2,2-azobis(methylbutyronitrile), AIBN (azobis(iso-butyronitrile)) and AMVN (zaobisdimethyl-valeronitrile).