▎ 摘　　要

NOVELTY - A double-layer coated silicon-based negative electrode material comprises core material, a coated carbon layer (A), and a coated carbon layer (B) from the inside to outside. The core material is uniformly arranged silicon and silicate. The coated carbon layer (A) is dense carbon with amorphous structure. The coated carbon layer (B) is a porous network structure formed by interlacing carbon nanotubes. The proportions of silicon, silicate and carbon in the negative electrode material are 40-80%, 10-57% and 1-10% respectively. USE - Double-layer coated silicon-based negative electrode material used in battery application. ADVANTAGE - The negative electrode material can effectively slow down the expansion, improve the conductivity of the material to ensure high rate performance in the battery application process, has high conductivity can effectively reduce the addition of single-walled carbon nanotubes in back-end pulping process, and reducing the cost of battery preparation. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of double-layer coated silicon-based negative electrode material, which involves (s1) crushing the silicon monoxide (SiOx) precursor material to obtain material (A), (s2) uniformly dispersing the material (A), carbon source and inorganic salt, and obtaining material (B) by liquid phase coating, (s3) mixing the material (B) with catalyst to obtain material (C), (s4) placing the material (C) in vapor deposition device for carbon coating, reacting at 700-900℃ for 3-5 hours, using argon as a protective gas during the deposition process, and coating. The carbon source is organic carbon source.