Lithium iron phosphate/graphene composite positive electrode material and preparation method thereof

The invention discloses a lithium iron phosphate/graphene composite positive electrode material and a preparation method thereof, PAH, PSS and LiFePO4 are sequentially adsorbed on the surface of graphene oxide on the basis of an electrostatic adsorption principle, and finally a final product is obtained through calcination treatment. In the calcining treatment process, on one hand, non-conductive graphene oxide is reduced into high-conductivity graphene, and meanwhile, the reduction of the graphene oxide can generate a plurality of microscopic hole defects on the surface of the graphene, so that the lithium ions can conveniently shuttle back and forth; on the other hand, the electrostatic layer of the PAH/PSS can be carbonized and used as a reducing agent for reducing Fe < 3 + > into Fe < 2 + > when lithium iron phosphate is calcined. The material with the particle size of 2-100 nm can be prepared, the particle size of lithium iron phosphate particles is greatly reduced, the transmission path of electrons and