An object of the invention is to provide such a battery that has a high capacity, is excellent in storage characteristics, cycle characteristics and continuous charging characteristics, and is small in gas generation amount, whereby size reduction and improvement in performance of a lithium secondary battery can be attained.
The present invention relates to a nonaqueous electrolytic solution comprising a lithium salt and a nonaqueous solvent dissolving the same, wherein the electrolytic solution contains, as the lithium salt, LiPF6 in a concentration of from 0.2 to 2 mole/L, and LiBF4 and/or a compound represented by the following formula (1) in a molar ratio of from 0.005 to 0.4 with respect to LiPF6, and the nonaqueous solvent mainly comprises (1) ethylene carbonate and/or propylene carbonate, (2-1) a symmetric linear carbonate, (2-2) an asymmetric linear carbonate, and (3) vinylene carbonate.