Patent ID: 7229718

Claim:
An electrolyte for a rechargeable lithium battery, comprising: 5 to 40 volume % of at least one fluorine-substituted ether compound represented by R 1 —O—R 2 , wherein R 1 and R 2 are each independently an alkyl group substituted with fluorine, having a substitution ratio of hydrogen with fluorine of 57 to 86%, a total viscosity of 0.9 to 2.3 cp, and a boiling point of at least 88° C.; 60 to 90 volume % of a non-aqueous organic solvent having a flash point of at least 80° C.; and, a compatibilizer selected from the group consisting of compounds represented by formulas 11 to 12: CH 3 COOCH 2 (CF 2 ) 3 CF 2 H and (11) CH 3 COOCH 2 CF 2 CF 2 H (12).