Research Progress of Silicon/Carbon Anode Materials for Lithium-Ion Batteries: Structure Design and Synthesis Method

Silicon has been considered as one of the best alternatives to replace widely used graphite anodes for lithium-ion batteries, owing to its high theoretical capacity, proper working voltage, abundant availability, and environmental friendliness. Nevertheless, there are many obstacles that hamper the practical applications of silicon anode materials such as huge volume change, low electrical and ionic conductivity, and unstable solid electrolyte interface (SEI), which lead to the pulverization of silicon and severe attenuation of capacity. Among numerous solutions, compounding with carbon is a promising and effective one that attracts more and more attention. In silicon/carbon (Si/C) hybrid anodes, Si acts as the active material that provides high capacity and carbon improves the conductivity as well as alleviates the expansion of Si. In this review, research progresses and developments of Si/C anode materials are summarized mainly from the point of structure design and synthesis methods. Issues and possible solutions are also discussed.