Lithium ion battery silicon substrate composite negative electrode materials and preparation method thereof

The present invention provides a negative electrode material for a lithium ion battery and a preparation method of the silicon compound, belonging to the technical field of lithium ion batteries. A lithium ion battery and the percentage composition of the silicon composite negative electrode material is prepared: Si: MgO: ratio of graphene is 23 ~ 56wt%: 12.1 ~ 75.4wt%: 2 ~ 12wt%. Magnesium thermal reduction method using a reducing agent as magnesium silicon oxides (SiOx, x = 0.5-2), prepared silicon / MgO composites, and then attached to the reaction product - on the surface of the silicon reaction product of - magnesium oxide catalyst used for catalytic chemical vapor deposition carbon graphene growth, the production of silicon / magnesium oxide / graphene composite negative electrode material. The resulting silicon lithium ion battery, the reduction of oxides of silicon, magnesium heat generated internally can alleviate the volume effect of magnesium oxide of silicon, external and internally generated magnesia acting as a catalyst, the catalytic graphene growth may further ease volume effect of silicon, and can significantly enhance the electrically conductive material.