Silicon-based negative electrode modified material, preparation method and application thereof

The invention discloses a silicon-based negative electrode modified material as well as a preparation method and application thereof. The silicon-based negative electrode modified material comprises a silicon-based negative electrode material and a surface coating layer coating the silicon-based negative electrode material, and the silicon-based negative electrode material is selected from at least one of silicon, silicon monoxide, modified silicon monoxide, silicon carbon and lithium silicon alloy. Or a silicon-based material formed by mixing at least one of silicon, silicon monoxide, modified silicon monoxide and a lithium-silicon alloy with carbon; and the surface coating layer is formed by compounding a conductive material, a lithium salt and an in-situ generated polymer electrolyte. The preparation method comprises the following steps: S1, mixing and stirring the amine curing agent, the diluent and the lithium salt until the lithium salt is dissolved; s2, adding epoxy resin into the solution in the S1, s