POSITIVE ELECTRODE ACTIVE MATERIAL AND PREPARATION METHOD THEREOF, POSITIVE ELECTRODE SHEET, AND SODIUM-ION BATTERY
A positive electrode active material has a chemical formula of NaANiFeMnCuAO, where A is selected from at least one of Zn, Mg, Ca, K, and Li, and the following conditions are satisfied: (1) 0.67≤x≤0.8…