| 摘要 |
PROBLEM TO BE SOLVED: To maintain high voltage and high energy density, and enhance the charging and discharging efficiency of a lithium negative electrode by adding carbonate having a specific structure substituent into a nonaqueous electrolyte, prepared by dissolving a lithium salt in an organic solvent. SOLUTION: Carbonate is a compound shown by Formula 1, the R of the formula 1 is a formula 2, a formula 3, or a formula 4. In formulas, R<1> to R<4> are H, a C1-6 alkyl group, a phenyl group, a benzyl group, or a benzyloxycarbonyl group, and (m), (n) are one to ten. For instance, bis(4- nitrophenyl)carbonate, 2-(trimethyl silyl)ethylp-nitrophenylcarbonate, and the like can be cited. In a lithium secondary battery provided with a negative electrode made of lithium or lithium alloy, a positive electrode capable of charging and discharging lithium ions, and nonaqueous electrolyte prepared by dissolving lithium salt in organic solvent, the dissolution of the lithium negative electrode electrochemically reacting with nonaqueous electrolyte during the repetition of charging and discharging cycle with respect to its surface, and the deposition of lithium metal become uniform. |
