| abstract |
Provided is a non-aqueous electrolyte secondary battery that uses lithium manganese composite oxide as a positive electrode active material, has excellent high-temperature charge storage characteristics and charge / discharge cycle characteristics, and has improved safety during overcharge. . A non-aqueous electrolyte secondary battery according to the present invention includes a positive electrode plate including a positive electrode mixture containing a positive electrode active material, a negative electrode plate, a non-aqueous electrolyte, and a pressure-sensitive safety mechanism that operates by increasing internal pressure. And the positive electrode active material includes a lithium manganese composite oxide containing 10 to 61% by mass of manganese element, and the positive electrode mixture includes lithium carbonate or calcium carbonate, phosphorus The non-aqueous electrolyte contains at least one organic additive selected from biphenyl, a cycloalkylbenzene compound, and a compound having a quaternary carbon adjacent to the benzene ring. [Selection figure] None |