Recent trends in silicon/graphene nanocomposite anodes for lithium-ion batteries

Even after the passage of three decades since the commercialization of first lithium-ion batteries (LIBs) and development of several other battery systems, LIBs continue to remain the battery of choice for increasingly expanding consumer electronics market. With the new found impulsion for developing electric and hybrid electric vehicles to minimize the dependence over fossil fuels and reduce carbon footprint of transport sector, efforts are required to enhance the energy and power delivery capabilities of LIBs. Silicon is a potential anode offering high theoretical capacity, surpassing that of even lithium. However, its pulverization due to cycling induced large volumetric fluctuations and limited electronic conductivity, drastically reduce its cycling stability. Graphene/reduced graphene oxide (rGO) with high electronic conductivity and flexibility, when composited with silicon is expected to overcome these challenges. Further, electrode structure and synthesis routes also significantly affect overall performance of the cell. Here, we review the progresses made in silicon/graphene nanocomposite chemistry for LIBs in the last five years. Additionally, different structural innovations such as core–shell, yolk–shell, porous, etc., for improving the electrode properties are also reviewed.