▎ 摘　　要

NOVELTY - Preparation of sodium-ion battery positive electrode material involves (s1) weighing each metal source according to the stoichiometric ratio of each metal ion in the positive electrode material, mixing with a modified yeast solution and nanofiber sol to obtain a precursor sol, (s2) heat-treating the precursor sol for filament separation to obtain a filament precursor sol, dehydrating, and sintering to obtain a carbon-coated positive electrode material, and (s3) mixing the carbon-coated positive electrode material with a phosphoric acid modifier, and sintering to form a phosphoric acid modified layer on the surface of the carbon-coated positive electrode material. The phosphoric acid modifier is one or more of phosphate containing sodium and/or nickel, pyrophosphate, hydrophosphate, and fluorinated phosphate. The modified yeast solution is a yeast solution modified by ammonium ion and/or phosphate ion. The nanofiber sol is prepared by mixing conductive nanofiber and polymer solution. USE - Preparation of material for positive electrode of sodium-ion battery (all claimed). ADVANTAGE - The method provides positive electrode material having high conductivity, high ion conductivity and excellent stability, thus effectively improving the kinetic performance and long-term stability of the sodium-ion battery and ensuring high capacity retention rate of sodium-ion battery during long-term use. DETAILED DESCRIPTION - Preparation of sodium-ion battery positive electrode material involves (s1) weighing each metal source according to the stoichiometric ratio of each metal ion in the positive electrode material e.g. sodium-nickel-magnesium-metal-based oxide of formula: NatNixMgyMzO2, where M is one or more of iron, manganese, cobalt, zinc, scandium, aluminum, titanium and zirconium, t is 0.6-1.15, x+y+z is 1, x is 0.2-0.6 and y is 0.01-0.16, mixing with a modified yeast solution and nanofiber sol to obtain a precursor sol, (s2) heat-treating the precursor sol for filament separation to obtain a filament precursor sol, dehydrating, and sintering to obtain a carbon-coated positive electrode material, and (s3) mixing the carbon-coated positive electrode material with a phosphoric acid modifier, and sintering to form a phosphoric acid modified layer on the surface of the carbon-coated positive electrode material. The phosphoric acid modifier is one or more of phosphate containing sodium and/or nickel, pyrophosphate, hydrogen phosphate, and fluorinated phosphate. The modified yeast solution is a yeast solution modified by ammonium ion and/or phosphate ion. The nanofiber sol is prepared by mixing conductive nanofiber and polymer solution. An INDEPENDENT CLAIM is included for positive electrode material, which comprises a positive electrode material, a heteroatom-doped carbon layer coated on the surface of the positive electrode material, and the phosphoric acid modified layer coated on the surface of the carbon layer. The heteroatom-doped carbon layer is a nitrogen and/or phosphorus-doped carbon layer.