| abstract |
(57) [Problem] When a mixed solvent of a cyclic carbonate and a chain carbonate is used as a non-aqueous electrolyte, a transesterification reaction by the chain carbonate occurs, and as an intermediate thereof, Alkoxide radicals, which are powerful nucleophilic reagents such as methoxy groups or ethoxy groups, are generated to promote the ring opening and decomposition of the cyclic ester, ethylene carbonate, to generate gas, or to dissolve the metal of the positive electrode active material. Then, the characteristics are degraded by destroying the crystal structure. SOLUTION: A non-aqueous electrolytic solution obtained by dissolving a supporting electrolyte having lithium as a cation in a solvent containing at least salicyl or salicylidene is used. |