▎ 摘　　要

NOVELTY - The method involves dispersing the nano silicon powder in water, and adding polydially dimethyl-ammonium chloride (PDDA) for stirring and ultrasonic reaction. The obtained solution is subjected to washing and centrifugation to obtain PDDA-silicon (Si) product. The obtained PDDA-Si product is added to the aqueous graphene oxide solution, and is stirred and ultrasonicated. The formaldehyde is added and stirred. The melamine is added and stirred. The final solution is hydrothermally reacted to dry the product after the hydrothermal reaction. The dried product is subjected to high temperature treatment to obtain a product. USE - Method for preparing lithium ion anode composite material of nitrogen-doped graphene/silicon three-dimensional structure. ADVANTAGE - The surface activation energy of nano-silicon particles can be changed. The problem of nano-silicon particles easy to agglomerate and difficult to disperse is alleviated. The nitrogen atom is introduced by the hydrothermal reaction, while reducing the graphene oxide to obtain nitrogen-doped graphene. DESCRIPTION OF DRAWING(S) - The drawing shows a photographic view of the material prepared by preparing nitrogen-doped graphene/silicon three-dimensional lithium ion negative electrode composite material.