A composite film of reduced graphene oxide modified vanadium oxide nanoribbons as a free standing cathode material for rechargeable lithium batteries

Hydrated vanadium pentoxide (V2O5·0.86H2O) nanoribbons modified with reduced graphene oxide (RGO) are synthesized by a hydrothermal process. These ribbons are 30 nm thick, 200 nm to 1 μm wide and above 50 μm long. Binder-free films are prepared by using these ribbons and annealed at 300 °C in nitrogen as the cathode for rechargeable lithium cells. The intertwining network of this free-standing VOx/RGO film provides efficient conduction pathways for electrons and short diffusion distances for Li ions. The electrochemical tests exhibit that this cathode film delivers a high reversible specific capacity (160 mAh g−1) and good cycling stability (133 mAh g−1 after 200 cycles) in the voltage range between 2.0 and 3.5 V.