▎ 摘　　要

NOVELTY - Preparation of composite material comprises taking graphene and metal ion compound at ratio of 1:0.03-0.5, emulsifying for 1-2 hours at 40-60 degrees C, and spray drying at 300-400 degrees C; mixing with iron source compound, phosphorus source compound, and lithium source compound salt, grinding for 5-8 hours at 25-45 degrees C, and spray drying under inert gas protection for 100-200 degrees C; and adding carbon source compound at ratio of 1:0.03-0.15, grinding for 2-5 hours at 30-50 degrees C, spray drying under inert gas protection at 100-200 degrees C, grading, sintering for 6-10 hours, and cooling to room temperature. USE - Method for preparing composite material (claimed) used for lithium ion battery. ADVANTAGE - The composite material has high charging capacity, high charging and discharging efficiency to more than 98%, where standard state is more than 92%, and high tap density, increases lithium ion battery energy density and ion diffusion coefficient, and has high electric conductivity and high multiplying discharge circuit performance. DETAILED DESCRIPTION - Preparation of composite material comprises taking graphene and metal ion compound at ratio of 1:0.03-0.5, emulsifying for 1-2 hours at 40-60 degrees C, and spray drying at 300-400 degrees C; mixing with iron source compound, phosphorus source compound, and lithium source compound salt at ratio of 1:1.1:0.85-1.15:0.6-0.8, grinding for 5-8 hours at 25-45 degrees C, and spray drying under inert gas protection at 100-200 degrees C; and adding carbon source compound at ratio of 1:0.03-0.15, grinding for 2-5 hours at 30-50 degrees C, spray drying under inert gas protection at 100-200 degrees C, grading, sintering for 6-10 hours, and cooling to room temperature.