NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

Disclosed is a low-cost nonaqueous electrolyte secondary battery which can be reversibly charged and discharged. This nonaqueous electrolyte secondary battery can be used for a long time by employing a stable nonaqueous electrolyte. Specifically disclosed is a nonaqueous electrolyte secondary battery comprising a positive electrode containing a positive electrode active material and capable of adsorbing and desorbing sodium, a negative electrode capable of adsorbing and desorbing sodium, and a nonaqueous electrolyte. This nonaqueous electrolyte secondary battery is characterized in that the positive electrode active material contains sodium, nickel, manganese and a transition metal which can be in a hexavalent state. Tungsten (W) may be used as the transition metal which can be in a hexavalent state. A sodium metal capable of adsorbing and desorbing sodium ions can be used as one example of the negative electrode.