▎ 摘　　要

NOVELTY - A rice hull-based silicon oxide/graphene aerogel composite cathode material is three-dimensional porous frame structure formed by mutually connecting random oriented sheet structure with drape structure and macropore/mesoporous structure. The particle diameter of silicon oxide is 40-200 nm and is uniformly dispersed in inner portion and surface of three-dimensional graphene aerogel network. The material has 8-23% silicon, 47-82% oxygen and 10-30% carbon, and has Brunauer, Emmett and Teller (BET) specific surface area of 160-210m2/g. USE - The rice hull-based silicon oxide/graphene aerogel composite cathode material is used as cathode material of lithium ion battery (claimed). ADVANTAGE - The material is safe, easy to recycle and convenient for mass production, has long cycle life, high specific capacity, wide raw material source, low price and easy operation, and realizes green pollution-free production. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) a method for preparing rice hull-based silicon oxide/graphene aerogel composite cathode material comprising: (i) cleaning rice hull by ultra-pure water, soaking in 0.1-5 mol/g acid solution, keeping at 80-100degrees Celsius for 8-24 hours and continuously stirring, centrifuging and separating and washing to neutral by ultra-pure water, putting in oven to dry, laying in ceramic boat, placing in tubular furnace with inert atmosphere, keeping at 400-600degrees Celsius for 1-4 hours at heating speed of 2-5degrees Celsius/minute, and naturally cooling to room temperature; (ii) putting in 1-3 mol/L sodium hydroxide solution, refluxing and stirring, keeping to 25-130degrees Celsius for 2-6 hours, filtering to obtain filtrate, adding hexadecyl trimethyl ammonium bromide (CTAB) into filtrate according to mass ratio of 1:0.1-0.5 g, dissolving solid, dropping acid solution at 25-80degrees Celsius to pH of 1-10 and keeping for 3-24 hours to obtain white precipitate, filtering and washing precipitate to neutral and drying; (iii) laying in ceramic boat, putting in tubular furnace, keeping under air atmosphere to 400-600degrees Celsius for 1-6 hours at heating rate of 2-5degrees Celsius/minute, naturally cooling, uniformly mixing with aluminum powder or magnesium powder or aluminum magnesium powder mixture according to mass ratio of 1-6:1-6 into ball milling tank, ball milling under inert gas for 10 minutes to 10 hours, putting in stainless steel closed reactor, heat preserving under inert gas atmosphere to 650-750degrees Celsius for 2-6 hours at heating rate of 2-15degrees Celsius/minute to reduce, and naturally cooling; and (iv) soaking in 0.1-2 mol/L acid solution for 4-24 hours, filtering and washing to neutral, vacuum drying, ultrasonically dispersing in 1-2 mg/mL graphene oxide solution for 1-2 hours, reacting to 150-180degrees Celsius for 4-12 hours, naturally cooling and filtering and washing with ultra-pure water, freeze-drying, putting in tubular furnace, keeping in hydrogen-argon mixed ga to 500-600degrees Celsius for 2-6 hours at heating rate of 2-5degrees Celsius/minute, and naturally cooling; and (2) a method of application comprising uniformly mixing rice hull-based silicon oxide/graphene aerogel composite cathode material, Ketjen black and polyvinylidene fluoride according to mass ratio of 5-8:4-1:1 to obtain solid mixture, mixing solid mixture with N-methylpyrrolidone according to mass ratio of 18-30:70-82, uniformly stirring to obtain slurry, coating on copper foil, drying, rolling to obtain lithium ion battery electrode sheet with thickness of 11-25 microm, taking lithium ion battery electrode sheet as working electrode, lithium sheet as counter electrode and microporous polypropylene-polyethylene film as diaphragm, using 1 mol/L lithium hexafluorophosphate as electrolyte, and assembling into CR2032 button type lithium ion battery in glove box filled with argon gas.