The invention discloses a
silicon carbon
composite material, and a preparation method and an application thereof. The preparation method comprises the following steps of performing wet process ball milling on glass
powder and a laminated layer carbon material to obtain a uniform mixed product of glass and the carbon material; next, performing uniform mixing and compacting on the product and
magnesium powder and fused salt to form an
ingot; and then performing a
magnesium thermal reaction, and carrying out
acid washing on the
reaction product to obtain a sandwich layer-shaped
porous silicon /
graphene-like structured
composite material. The preparation method are simple in steps and easy to implement, and the raw materials are wide in resource; more importantly, the mixture is made into the
ingot through the compacting process, and then the
magnesium thermal reaction is performed, so that the tap density of the
silicon carbon negative
electrode material is greatly improved, and the volumetric specific capacity of the negative
electrode material is improved; meanwhile, by compounding with the
graphite and other carbon material to form the sandwich-like structure, the
electronic conductivity of the material is improved effectively, and the compatibility between the
silicon base material and an
electrolyte can be improved, thereby improving cycle performance and rate capability of the material; and therefore, the silicon carbon
composite material can be applied to the negative
electrode material with
high power density and
high energy density of the
lithium ion battery.