▎ 摘　　要

NOVELTY - Preparing three-dimensional porous silicon/graphene composite cathode material involves pretreating the silica source by a heating process. The sulfuric acid solution dispersed with graphene or graphene oxide is added into the pretreated silicon dioxide source, purified under stirring and dispersing. The silicon dioxide source and the graphene or graphene oxide are in-situ compounded in the purification process, and then sequentially filtered, washed with deionized water and dried to obtain an intermediate product A. The intermediate product A is processed through a thermal reduction process to obtain an intermediate product B. The acid washing is carried out on the intermediate product B, washed with deionized water, filtered and dried. USE - Method for preparing three-dimensional porous silicon/graphene composite cathode material used in lithium-ion battery (claimed). ADVANTAGE - The method enables to utilize the synergistic effect of three-dimensional porous silicon and graphene to achieve complementary advantages, and the micro-nano pores in the porous silicon well suppress the volume expansion of itself during the lithium intercalation process. The composite of graphene alleviates the volume effect of the electrode material, which improve the conductivity, cycle stability, charge-discharge efficiency, rate capability and other electrochemical properties of the silicon electrode, and has high value in pure electric and hybrid electric vehicle applications.