NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery having an improved cycle life, a long service life and high energy density. SOLUTION: The nonaqueous electrolyte secondary battery comprises a charging and discharging possible positive electrode, a nonaqueous electrolyte and a charge and discharge possible negative electrode. The negative electrode has a hexagonal closest packing structure consisting of at least two elements and contains an alloy having a Ni2In structure.