LITHIUM ION NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

There is provided a lithium ion secondary cell excellent in charging and discharging cycle characteristics. A lithium ion secondary cell includes an electrode body including a positive electrode having a positive electrode active material, a negative electrode having a negative electrode active material, and a separator, and a non-aqueous electrolyte containing a lithium salt as a supporting salt in an organic solvent, the electrode body and the non-aqueous electrolyte being accommodated in a case. The positive electrode active material is a lithium transition metal oxide having a spinel type structure. The electrolyte contains a compound represented by a chemical formula (I) in an amount of beta mol relative to the total content alpha mol of moisture to be mixed in the cell. beta satisfies -0.8@log(beta/alpha)@1.5.