The invention relates to the technical field of
sodium ion battery positive
electrode materials, and provides a
sodium ion battery layered high-entropy
oxide positive
electrode material, a preparation method thereof, a positive
electrode plate and a
sodium ion battery. The chemical general formula of the layered high-entropy
oxide positive
electrode material provided by the invention is NaxNiaMnbMcO2, wherein M is at least four of Li, Zn, Cu, Mg, Ca, Fe, Al, Co, Y, Ru, Ti, Ir, Sb, Te, Sn and Nb. The positive
electrode material provided by the invention is good in
structural stability, and can effectively inhibit
phase change, so that the cycle stability is improved, and the electrochemical performance of sodium storage is enhanced. According to the invention, the precursor is obtained by adopting a
sol-
gel method, and then is sintered into a phase by adopting a
solid-
phase reaction method, so that the obtained positive
electrode material is uniform in particle distribution and shows good
structural stability, and the obtained positive electrode material is obviously superior to a material prepared by adopting a common high-temperature
solid-
phase method in the aspects of reversible capacity and electrochemical reversibility.