Patent ID: 7026073

Claim:
A non-aqueous electrolyte secondary battery comprising a positive electrode, a negative electrode and a non-aqueous electrolyte, wherein said non-aqueous electrolyte comprises a non-aqueous solvent and a solute dissolved in said non-aqueous solvent, wherein said non-aqueous solvent comprises: (A) a cyclic carboxylic acid ester; (B) 0.5 to 20 volume percent of the total volume of non-aqueous solvent of a cyclic carbonic acid ester having at least one carbon-carbon unsaturated bond; and (C) a cyclic carbonic acid ester having no carbon-carbon unsaturated bond, and wherein said cyclic carbonic acid ester having at least one carbon-carbon unsaturated bond (B) comprises vinylethylene carbonate and vinylene carbonate.