▎ 摘　　要

NOVELTY - A graphene coated olivine lithium iron phosphate compound material preparation method involves weighing oxidized graphite alkene, and mixing with de-ionized water or organic solvent at room temperature, followed by subjecting mixture to perform ultrasonic treatment for 10-60 minutes and magnetic force stirring to prepare the graphene oxide solution. Iron salt as reducing agent is weighed (1-100) times of graphene and mixing with lithium salt and phosphate, where the mass ratio of lithium salt, iron salt and phosphate is (1-3):(1-3):1. The obtained mixture is added with surfactant. USE - Method for preparing graphene coated olivine lithium iron phosphate compound material. ADVANTAGE - The method enables preparing compound material with better bonding force, improved conductivity and reduced contact resistance between lithium iron phosphate and graphite in an effective manner. DETAILED DESCRIPTION - A graphene coated olivine lithium iron phosphate compound material preparation method involves weighing oxidized graphite alkene, and mixing with de-ionized water or organic solvent at room temperature, followed by subjecting mixture to perform ultrasonic treatment for 10-60 minutes and magnetic force stirring for 10-30 minutes to prepare the graphene oxide solution. Iron salt as reducing agent is weighed (1-100) times of graphene and mixing with lithium salt and phosphate, where the mass ratio of lithium salt, iron salt and phosphate is (1-3):(1-3):1. The obtained mixture is added with surfactant and stirred at room temperature under magnetic force, where the mass of surfactant is 1-10 times of lithium salt. The obtained mixture is dissolved in de-ionized water, and graphene oxide solution is dropped into the mixture, followed by stirring for 5-15 minutes and transferring into a high pleasure reactor at 120-180 degrees C for 1-24 hours. The resultant mixture is taken out and put in a centrifuge at 1000-10000 rpm, followed by washing with ethanol and de-ionized water for 3-5 times and drying in vacuum dryer at 40-60 degrees C for 3-10 hours under protection atmosphere of 500-1000 degrees C. The obtained mixture is annealed for 3-10 hours to obtain the graphene coated olivine lithium iron phosphate composite material.