| 摘要 |
In order to provide a lithium secondary battery having high terminal-to-terminal open circuit voltage at the end of charge, suppressed amount of evolved gas on continuous charge, and superior cycle characteristics, the electrolyte solution thereof comprises either both vinylethylene carbonate compound and vinylene carbonate compound, lactone compound having a substituent at its ± position in an amount of 0.01 weight % or more and 5 weight % or less, lactones having an unsaturated carbon-carbon bond in an amount of 0.01 weight % or more and 5 weight % or less, or sulfonate compound represented by the formula below. In the formula, L represents a bivalent connecting group consisting of at least one carbon atom and hydrogen atoms, and R30 represents, independently of each other, an unsubstituted or fluorine-substituted aliphatic saturated hydrocarbon group. |
