▎ 摘　　要

NOVELTY - A lithium-rich manganese-based positive electrode material comprises substrate and graphene-based/metal phosphate composite coating layer coated on the surface of the substrate. The substrate is lithium manganite-lithium metal oxide. USE - Lithium-rich manganese-based positive electrode material for lithium ion battery (claimed) and electric automobile. ADVANTAGE - The lithium-rich manganese-based positive electrode material uses graphene oxide as a template to prepare the graphene-based/metal phosphate composite coating layer by in-situ growth, which avoids the formation of island-like structures on the surface of the lithium-rich manganese-based positive electrode substrate in the conventional coating method, so that the overall graphene/metal phosphate composite is tightly and firmly coated on the surface of the lithium-rich manganese-based positive electrode substrate, and the coating is more uniform, which significantly improves the thermal stability, cycle performance and multiplication power performance of the material. DETAILED DESCRIPTION - A lithium-rich manganese-based positive electrode material comprises substrate and graphene-based/metal phosphate (M2PO4) composite coating layer coated on the surface of the substrate. The substrate is lithium manganite-lithium metal oxide of formula: xLi2MnO3.(1-x)LiM1O2, where x is 0-1 (excluding 0 and 1), M1 is nickel, cobalt and/or manganese, and M2 is iron, manganese, vanadium and/or cobalt. An INDEPENDENT CLAIM is included for preparation of the lithium-rich manganese-based positive electrode material, which involves ultrasonically dispersing graphene oxide in solvent, adding metal salt solution, phosphoric acid solution and substrate, filter pressing, vacuum drying, and sintering in protective atmosphere.