▎ 摘　　要

NOVELTY - Polyanionic electrode material i.e. sodium-vanadium-phosphorus-oxygen complex (I) is new. USE - (I) is useful in sodium ion battery (claimed). ADVANTAGE - The polyanion electrode material not only improves the problem of low conductivity of the sodium vanadium phosphate material, ensures charging and discharging electrochemical performance of super-large multiplying power, but also can supplement the first Coulomb efficiency of the full battery system cathode hard carbon loss. DETAILED DESCRIPTION - Polyanionic electrode material i.e. sodium-vanadium-phosphorus-oxygen complex of formula (Na3V2MxP3-0.5xO12) (I) is new. M = doping metal element including Sm, Eu, Tm, Yb, Y or Sc; and x = 0-4. INDEPENDENT CLAIMS are also included for: Preparation of (I); and Sodium-ion battery comprising anode sheet, cathode sheet, separator and electrolyte, where separator is configured to isolate the anode sheet from the cathode sheet, and active material in the anode sheet is the polyanion electrode material.