▎ 摘　　要

NOVELTY - A graphene-ferric fluoride composite cathode material preparing method involves reacting ferric oxalate, cobalt hydroxide and hydrogen fluoride solution followed by heating, continuously stirring, filtering, washing with ethanol, drying and heating obtain a cobalt-doped iron fluoride powder. A silicon dioxide-doped graphite mixture is prepared by dispersing graphite oxide in de-ionized water and processing in ultrasonic wave. The obtained cobalt-doped iron fluoride powder and silicon dioxide-doped graphite mixture are mixed in a ball mill and heated to obtain a cathode material. USE - Method for preparing a graphene-ferric fluoride composite cathode material that is utilized in a lithium ion battery. ADVANTAGE - The method enables preparing the graphene-ferric fluoride composite cathode material with better conductivity and high circulating stability. The cathode material prolongs the service life of a lithium ion battery. DETAILED DESCRIPTION - A graphene-ferric fluoride composite cathode material preparing method involves reacting ferric oxalate, cobalt hydroxide and hydrogen fluoride solution under sealed condition at room temperature for 3-5 hours followed by heating to 85-90 degrees C, continuously stirring for 20-30 hours, filtering, washing with ethanol, drying and heating under vacuum condition to obtain a cobalt-doped iron fluoride powder, where concentration of hydrogen fluoride solution is 25-30 wt.%. Graphite oxide is dispersed in 600-800 mL of de-ionized water, and processed in ultrasonic wave for 12-15 hours to obtain graphite oxide nano-sheet. Nano-silicon powder is added to graphite oxide nano-sheet in a ratio of 1: 0.2-0.5, and completely stirred to obtain silica nano-graphite oxide film with mixed dispersion. Hydrazine hydrate is added to the nano-silicon powder and graphite oxide nano-sheet containing disperse system, and stirred at 110-120 degrees C and refluxed for 20-30 hours. The resulting mixture is filtered, washed with de-ionized water and dried to obtain silicon dioxide-doped graphite mixture. The obtained cobalt-doped iron fluoride powder and silicon dioxide-doped graphite mixture are mixed in a ball mill for 3-6 hours at a milling speed of 300-400 revolution/minute and heated at 170-200 degrees C to obtain graphene-ferric fluoride composite cathode material.