Progress of silicon and graphene composites in lithium-ion battery anodes

As society progresses, the need for high-power, long-life energy supply devices gradually increases. Lithium-ion batteries (LIBs) with large energy reserves and high power have recently become the preferred choice. The anode of LIBs plays a crucial role in battery performance, safety, and cycle life. Typically, graphite materials are used for LIBs anodes. Still, they have drawbacks such as low first-time Coulombic efficiency, capacity degradation, safety issues, short cycle life, insufficient gram capacity, and purity and side reactions, which limit the application of LIBs. Therefore, new harmful electrode materials are in demand. Graphene and silicon are both environmentally friendly and sustainable materials. They both have the advantages of high theoretical capacity and high energy density, which are critical materials for developing LIBs. Combining the two can exert a synergistic effect and jointly improve the cycle stability of the battery. In this paper, we review the preparation methods of graphene and silicon composites in recent years, including mechanical ball milling and hydrothermal and thermal reduction methods. In addition, graphene and silicon composites have been explored for LIBs applications.