▎ 摘　　要

NOVELTY - Preparing lithium-silicon Li21Si5 and graphene composite material comprises (i) pouring palladium and nano silicon powder having a mass ratio of 0.6-1.7:1 into ethanol to obtain mixed solution, dispersing the mixed solution ultrasonically, mixing the nano silicon powder and graphene uniformly and drying to obtain mixed powder of nano silicon powder and graphene uniformly distributed, (ii) taking lithium metal according to the mass ratio of lithium to silicon in the mixed powder obtained in the step (i) is 1.2-1.5:1, then laminating mixed powder obtained in the step (i) and the lithium metal in a mold, then simultaneously realizing lithiation and structural densification of silicon by a discharge plasma sintering technique and grinding the sintered bulk material to obtain final product, where the sintering process parameters are: pressure is 10-20 MPa, temperature is 260-300 degrees C, and the time is 30-60 minutes. USE - The material is useful for lithium ion battery cathode (claimed). ADVANTAGE - The method has excellent dispersibility of graphene in Li21Si5 to ensure a large number of well-bonded two-phase interfaces, and the effect of graphene on the electrochemical performance of Li21Si5 is more remarkable.