Large Reversible Capacity of Graphene Electrodes Used in Lithium-ion Batteries

摘要

High quality graphene sheets (GSs) were prepared from natural graphite by oxidation, rapid thermal expansion and ultrasonic treatment. The morphology and structure of GSs were systematically investigated by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier tansform infrared spectroscopy (FT-IR) and Raman spectroscopy. It was found that the GSs electrode used in lithium-ion battery (LIB) exhibited a relatively high reversible capacity of 902 mA h/g at a current density of 50 mA/g. After 50 cycles, the reversible capacity was still kept at 734 mA h/g.