▎ 摘　　要

NOVELTY - A graphene anode material preparing method involves weighing a graphite and sodium nitrate into a beaker, and stirring, adding a sulfuric acid, potassium manganate, water and hydrogen peroxide to the solution, stirring and washing to obtain graphite oxide. The obtained oxide is dispersed in water, and sulfuric acid is added to the suspension liquid, and the mixture is placed into a reaction kettle. Lithium iron phosphate, carbon nano-tubes, graphene and polyvinylidene fluoride are added to the tank and dry mixed, the water is added to the solution and stirred. The resulting rheological body is immersed in the interlayer of graphene oxide to form an intercalation composite, which is dried to prepare a composite precursor. The precursor is ground to obtain a powder, which is pre-decomposed into an intermediate product. The product is calcined in a protective atmosphere furnace, and cooled to obtain a calcined product, which is pulverized and sorted to obtain the finished product. USE - Method for preparing graphene cathode material for use in lithium ion battery. ADVANTAGE - The method enables preparing graphene cathode material with enhanced conductivity, capacity, safety, rate, and cycle performance, in simple and cost effective manner. DETAILED DESCRIPTION - A graphene cathode material preparing method involves weighing 6-10 parts graphite and 2-4 parts sodium nitrate into a beaker, and mechanically stirring vigorously, slowly adding 100-150 mL concentrated sulfuric acid to the solution, and stirring for 40-60 minutes, slowly adding 15-25 parts potassium manganate to the solution after 0.5 hours addition, after stirring for 20 hours, increasing the viscosity of the reactants, and stirring to obtain a paste-like purple-red material after standing for 6-10 days, slowly adding 450-550 mL deionized water and 25-35 mL hydrogen peroxide respectively to the solution, at the time the color of the solution becomes more pronounced bright yellow after fully reaction of the solution, centrifuging and washing to obtain graphite oxide. The graphite oxide suspension liquid is prepared by dispersing the graphite oxide in water, concentrated sulfuric acid is added to the suspension liquid, and the mixture is uniformly dispersed to obtain a mixed liquid, placed the mixture into a reaction kettle and reacted at 200-250 degrees C for 15-20 hours and washed to obtain three-dimensional reduced graphene oxide. 80-100 parts lithium iron phosphate, 1-2 parts carbon nano-tubes, 3-5 parts graphene and 1-2 parts polyvinylidene fluoride are added to the stirred tank, the revolution speed is set to 15-25 rpm/minutes, the dispersion speed is 200- 400 rpm/minutes and mixed for 20-40 minutes. 6-8 times of deionized water of the mixture mass is added, at a revolution speed of 20-30 rpm/minutes, a dispersion speed of 600-800 rpm/minutes, stirred for 10-15 minutes, the scraper the wall is stopped and the revolution speed is set at 25-35 rpm/minutes, the dispersion speed is set to 800-1200 rpm/minutes and stirred for 30-50minues to obtain a dispersion. The obtained dispersion is stirred at a temperature of 60-80 degrees C, the resulting rheological body is immersed in the interlayer of the three-dimensional reduced graphene oxide to form an intercalation composite and the intercalation composite is dried to constant weight to prepare a composite precursor. The composite precursor is ground to obtain a powder, the powder is pre-decomposed into an intermediate product in a protective atmosphere furnace of an inert gas to control the pre-decomposition temperature at 250-300 degrees C for 3-5 hours. The intermediate product is calcined in a protective atmosphere furnace of a reducing gas, and cooled to room temperature to obtain a calcined product, where the calcination temperature is 500-600 degrees C and the calcination time is 8-10 hours. The calcined product is pulverized and sorted to obtain the finished product.