POSITIVE ELECTRODE MATERIAL FOR SODIUM SECONDARY BATTERY, METHOD FOR PRODUCING THE POSITIVE ELECTRODE MATERIAL FOR SODIUM SECONDARY BATTERY, ELECTRODE FOR SODIUM SECONDARY BATTERY USING THE POSITIVE ELECTRODE MATERIAL FOR SODIUM SECONDARY BATTERY, SODIUM SECONDARY BATTERY INCLUDING THE ELECTRODE FOR SODIUM SECONDARY BATTERY, AND ELECTRICAL DEVICE USING THE SODIUM SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To provide a sodium secondary battery having a higher charge/discharge capacity and a higher capacity retention rate than conventional ones.SOLUTION: A positive electrode material for a sodium secondary battery comprises a sodium-containing transition metal oxide represented by composition formula: Na(MnCoNi)O, where composition ratios x, y and z satisfy 0.5x1.0, 0.60y0.80, 0.05z0.20 and 0.051-y-z0.25.