NONAQUEOUS SECONDARY BATTERY

摘要

A positive electrode of a nonaqueous secondary battery has a positive electrode active material including at least one selected from lithium metal complex oxides having a layered rock salt structure, lithium metal complex oxides having a spinel structure, and polyanion based materials. The electrolytic solution contains a metal salt whose cation is an alkali metal, an alkaline earth metal, or aluminum, and an organic solvent having a heteroelement. Regarding an intensity of a peak derived from the organic solvent in a vibrational spectroscopy spectrum of the electrolytic solution, when an intensity of an original peak of the organic solvent is represented as Io and an intensity of a peak resulting from shifting of the original peak is represented as Is; Is>Io is satisfied. The nonaqueous secondary battery may have a usage maximum potential of the positive electrode of not lower than 4.5 V when Li/Li+ is used for reference potential.

主权项

1. A nonaqueous secondary battery comprising a positive electrode, a negative electrode, and an electrolytic solution, wherein:
the electrolytic solution contains a metal salt whose cation is an alkali metal, an alkaline earth metal, or aluminum, and an organic solvent having a heteroelement; regarding an intensity of a peak derived from the organic solvent in a vibrational spectroscopy spectrum of the electrolytic solution, Is>Io is satisfied when an intensity of an original peak of the organic solvent is represented as Io and an intensity of a peak resulting from shifting of the original peak is represented as Is, or d/c obtained by dividing a density d (g/cm3) of the electrolytic solution by a concentration c (mol/L) of the electrolytic solution is within a range of 0.15≦d/c≦0.71; and at least one of the following conditions 1 to 4 is satisfied. Condition 1: The positive electrode has a positive electrode active material including a lithium metal complex oxide with a layered rock salt structure. Condition 2: The positive electrode has a positive electrode active material including a lithium metal complex oxide with a spinel structure. Condition 3: The positive electrode has a positive electrode active material including a polyanion based material. Condition 4: A usage maximum potential of the positive electrode in the nonaqueous secondary battery is not lower than 4.5 V when Li/Li+ is used for reference potential.