Graphene-Based Composite Materials as Anodes for Improving the Performance of Lithium-Ion Batteries

Abstract

With the rapid popularization and development of electric vehicles, drones, and mobile communication devices, the performance requirements for lithium-ion batteries continue to rise. Lithium-ion batteries, owing to their small size, high energy density, and low environmental impact, have been widely applied in electric vehicles and other energy-storage fields. However, the current mainstream anode materials still suffer from obvious shortcomings: artificial graphite has a theoretical capacity of only 372 mAh·g⁻¹, which cannot meet the demand for high energy density; although silicon–carbon anodes can reach 600–1500 mAh·g⁻¹, they undergo 300%–400% volume expansion during charge–discharge cycling, causing electrode pulverization and capacity fading. Graphene, as a two-dimensional nanomaterial with excellent electrical conductivity, mechanical properties, and large specific surface area, is an ideal material for improving anode performance. This paper reviews the application of graphene and its composites in lithium-ion battery anodes, analyzes the improvement brought by graphene–silicon, graphene–tin/tin oxide, and graphene–carbon composite systems, clarifies the mechanism by which graphene acts as a conductive network and structural reinforcement, and discusses the challenges in scalable production, cost, and batch consistency. The results show that graphene can effectively reduce the internal resistance of the electrode, buffer volume deformation, and enhance structural stability, and that composite structures can achieve synergistic optimization of capacity and cycling performance. In the future, by developing green and low-cost preparation processes and designing multi-scale composite structures, graphene-based anodes will find wider application in high-energy-density lithium-ion batteries.