Non-aqueous electrolyte and lithium secondary battery using the same

摘要

A non-aqueous electrolyte comprising (i) a non-aqueous solvent, especially mainly composed of a cyclic carbonate and a cyclic ester and optionally a linear carbonate, and (ii) an electrolyte salt, especially LiBF₄, dissolved therein and (iii) a vinyl sulfone derivative having the formula (I): wherein R indicates a C₁ to C₁₂ alkyl group, C₂ to C₁₂ alkenyl group, or C₃ to C₆ cycloalkyl, and also a lithium secondary battery using the same are disclosed.