| 摘要 |
PROBLEM TO BE SOLVED: To provide a lithium secondary battery of a nonaqueous electrolyte system with high initial capacity which can suppress rise of internal resistance at high-temperature environment and is free from leaking. SOLUTION: A nonaqueous electrolyte of a nonaqueous electrolyte system lithium secondary battery contains a compound expressed in formula I, where, R<1> , and R<2> are each independently an alkyl group, a halogenized alkyl group, an aryl group, or alkyl-substituted aryl group, or R<1> and R<2> can be combined together and also form a saturated heterocycle together with nitrogen atom with which they are combined; each of X<1> to X<5> represents independently hydrogen atom, halogen atom, an alkyl group, an alkoxy group, an aryl group, an alkyl-substituted aryl group, a cyan group, a nitro group, a dialkylamino group, or a group -O-CO-N-R<3> (R<4> ), provided, at least one of X<1> to X<5> denotes halogen atom, and R<3> and R<4> each represent an alkyl group. |
