| abstract |
PROBLEM TO BE SOLVED: To provide a non-aqueous electrolyte having a high overcharge prevention effect and excellent in high-temperature storage characteristics, and a lithium secondary battery using the same, which has enhanced safety during overcharge. . SOLUTION: A fluorine atom-substituted aromatic compound and a compound having a sulfonyl group are added to an electrolytic solution composed of a non-aqueous solvent and a lithium-containing electrolyte. As the fluorine atom-substituted aromatic compound, naphthalene, fluorene or biphenyl substituted with a fluorine atom is preferable, and as the compound having a sulfonyl group, a sultone having an unsaturated hydrocarbon group, a sulfonic acid ester having an aryl group, Alternatively, sulfonimide is preferred. Vinylene carbonates may be further added to the electrolytic solution. Such a non-aqueous electrolyte can be used as an electrolyte for a lithium secondary battery. |