A review of recent developments in Si/C composite materials for Li-ion batteries

Rechargeable lithium batteries play an increasingly significant role in our daily lives. Hence, the development of high capacity secondary lithium batteries has become a research hotspot. In the past decade, silicon has been extensively studied as anode material for Li-ion batteries because of its extremely high specific capacity. However, the dramatic volume change and troublesome SEI (solid electrolyte interface) issues during lithiation and delithiation hinder the commercialisation of Si anode materials. To circumvent these issues, carbon materials have been widely utilized in composites with Si materials due to their excellent electrochemical and physical properties. Established preparation methods of Si/C composite materials facilitate the design of novel Si/C composites. Different forms of carbon can improve the electrochemical performance of silicon materials in different ways. Advanced characterisation techniques further verify and explain the contribution of carbon materials to the performance improvement of Si. Si/C composite materials are anticipated to be the anode material for the next generation of commercial lithium batteries.