▎ 摘　　要

NOVELTY - A silicon carbon cathode material comprises core and shell. The core is sphere or sphere formed by nano-silicon particles and carbon material. The carbon material is coated on surface of nano-silicon particles and filled in gap between nano-silicon particles. The core is provided with pore canals. The shell is porous silicon dioxide layer and amorphous carbon layer coated outside core. A gap is between silicon dioxide layer and amorphous carbon layer. The shell is provided with wrinkle outer surface. USE - Silicon carbon cathode material. ADVANTAGE - The material has good conductivity, good multiplying power performance, stable cycle performance and electrolyte infiltration and lithium ion storage site and transmission channels, shortens distance of lithium ion diffusion, buffers expansion of nano-silicon by gap between core and shell layer to inhibit volume change of material, and improves circulation performance. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a method for preparing silicon carbon cathode material comprising: uniformly dispersing nano-silicon particles, binder, carbon material precursor and pore-forming agent in dispersion to prepare slurry, spray drying to obtain spherical or spherical particles, calcining under inert atmosphere at 500-1000degrees Celsius for 3-36 hours, and cooling to obtain sphere or sphere-like core with pore canals; soaking core with diluted acid for 0.5-3 hours under stirring, cleaning by deionized water, filtering, vacuum drying, adding core into mixed solution of ethanol and water with mass ratio of 1-9:1, adding 30 wt.% ammonia water, uniformly stirring, adding tetraethyl orthosilicate, stirring and reacting for 1-24 hours, filtering and washing filter cake to neutral, and vacuum drying; and mixing powder and organic carbon source according to mass ratio of 1-9:1, calcining under inert atmosphere to 500-1000degrees Celsius for 1-24 hours, soaking product in 3-40 wt.% hydrofluoric acid, stirring for 0.5-5 hours, filtering, solid washing to neutral, and drying. The inert atmosphere is nitrogen, argon gas or helium gas atmosphere. The organic carbon source is sucrose, glucose, citric acid, asphalt, phenolic resin, polythiophene, polypyrrole or polyaniline. The mass ratio of core, ammonia water, tetraethyl orthosilicate and mixed solution of ethanol and water is 1-10:5-25:2-20:1-10.