▎ 摘　　要

NOVELTY - A nitrogen doped graphene coated micro-silicon composite material preparing method involves mixing graphene oxide, natural graphite, sulfuric acid and potassium permanganate to obtain graphene oxide aqueous solution, centrifuging the graphene oxide solution to obtain supernatant, centrifuging the supernatant to obtain precipitate, adding graphene oxide solution to deionized water and silicon granule to obtain mixed solution, spray drying the solution to obtain composite material, followed by placing the composite material in reaction kettle and drying to obtain finished product. USE - Method for preparing nitrogen doped graphene coated micro-silicon composite material that is utilized for lithium ion battery cathode material. DETAILED DESCRIPTION - A nitrogen doped graphene coated micro-silicon composite material preparing method involves mixing graphene oxide, natural graphite, concentrated sulfuric acid as a inserting layer agent and potassium permanganate as oxidizing agent to obtain graphene oxide aqueous solution, centrifuging the graphene oxide aqueous solution to speed of 3000 rpm to obtain supernatant, centrifuging the supernatant to speed of 8000 rpm to obtain precipitate, adding graphene oxide aqueous solution to deionized water and micro silicon granule to obtain silicon and graphite mixed solution, spray drying or freeze drying the solution to obtain graphene oxide/micron silicon composite material, followed by placing the composite material in reaction kettle with hydrazine hydrate and drying at 120 degrees C for 2 hours to obtain nitrogen doped graphene coated micro-silicon composite material.