Laterally Confined Graphene Nanosheets and Graphene/SnO_(2) Composites as High-Rate Anode Materials for Lithium-Ion Batteries

High-rate anode materials for lithium-ion batteries are desirable for applications that require high power density.We demonstrate the advantageous rate capability of few-layered graphene nanosheets,with widths of 100-200 nm,over micro-scale graphene nanosheets.Possible reasons for the better performance of the former include their smaller size and better conductivity than the latter.Combination of SnO_(2)nanoparticles with graphene was used to further improve the gravimetric capacities of the electrode at high charge-discharge rates.Furthermore,the volumetric capacity of the composites was substantially enhanced compared to pristine graphene due to the higher density of the composites.