Preparation method of graphene-loaded carbon-silicon monoxide double-layer coated nano silicon negative electrode material

The invention belongs to the technical field of preparation of lithium ion battery electrode materials, and particularly relates to a preparation method of a graphene-loaded carbon-silicon monoxide double-layer coated nano silicon negative electrode material, which comprises the following steps: by taking metal silicon and crystalline flake graphite as main raw materials, mixing citric acid monohydrate, ethylene glycol and water; heating, refluxing and stirring to obtain a silicon powder surface modifier; the preparation method comprises the following steps: crushing and grinding blocky metal silicon into powder, mixing silicon powder with a silicon powder surface modifier, carrying out ball milling treatment to obtain a pasty product, and carrying out vacuum drying and heat treatment in an argon atmosphere to obtain a light brown powdery product; mixing the product with crystalline flake graphite and phenolic resin liquid, and carrying out ball milling to obtain a black pasty precursor; and carrying out vacu