Preparation method of cation-substituted modified sphere-like sodium nickel manganese oxide positive electrode material

The invention relates to the technical field of preparation of solid electrolyte materials of sodium ion batteries, in particular to a preparation method of cation-substituted modified spheroidal sodium nickel manganese oxide. The invention discloses a preparation method of cation-substituted modified sodium nickel manganese oxide, which comprises the following steps: carrying out coprecipitation reaction on soluble nickel manganese metal salt, soluble substituted metal M salt and a carbonate precipitation complexing agent to obtain a sphere-like carbonate precursor, calcining the carbonate precursor to obtain a layered oxide precursor, and calcining the layered oxide precursor to obtain the cation-substituted modified sodium nickel manganese oxide. And uniformly mixing the layered oxide precursor with a sodium salt, and calcining to obtain the cation-substituted sodium nickel manganese oxide positive electrode material. The substituted and modified sodium nickel manganese oxide positive electrode material pr