Abstract: A lithium battery which includes an electrode assembly having a cathode, an anode and a separator interposed between the cathode and the anode, a gel electrolyte prepared by curing a composition consisting of a polysiloxane compound or a polysiloxane-polyoxyalkylene compound, a polyethylene glycol derivative, and an organic solvent containing a lithium salt. The lithium battery has improved reliability and safety since a swelling phenomenon due to an electrolytic solution is effectively suppressed and leakage of the electrolytic solution is prevented.

Abstract: An organic electrolytic solution and a lithium secondary battery employing the same are provided. The organic electrolytic solution contains an organic solvent and a lithium salt and the organic solvent includes 20 to 60% by volume of ethylene carbonate, 20 to 70% by volume of dialkyl carbonate and 5 to 30% by volume of a fluorinated toluene compound. The organic electrolytic solution has improved high-temperature exposure characteristic by adding a fluorinated toluene compound having a high boiling point to mixed solvents of ethylene carbonate and dialkyl carbonate. The lithium secondary battery employing the organic electrolytic solution is excellent in the high-temperature exposure characteristic, while maintaining good discharge capacity and lifetime characteristics.