SEPARATOR AND NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To provide a separator and a nonaqueous electrolyte secondary battery, capable of suppressing to a minimum reduction in energy concentration caused by irreversible capacity at a first charging/discharging.SOLUTION: The separator includes a Li-containing oxide in which air gaps are formed by Li desorption at a first charging time and Li is not inserted at a time of discharging. The nonaqueous electrolyte secondary battery includes the separator.