Half-cell and full-cell applications of horizontally aligned reduced oxide graphene/V2O5 sheets as cathodes for high stability lithium-ion batteries

Abstract

2D hybrid sheets of V₂O₅ and reduced graphene oxide (rGO/V₂O₅) have been synthesized using a hydrothermal method. With the addition of tiny amount of rGO content (6.25%), the proper conductivity and accessibility of hybrid nanosheets for lithium ion migration are obviously promoted. Compared with the bare V₂O₅ sheets, the rGO/V₂O₅ hybrid sheets exhibited enhanced electrochemical performance in terms of improved cycling stability (nearly 81.5% capacity retention after 200 cycles), high reversible capacity of 249 mA h g⁻¹ at a current density of 100 mA g⁻¹ and good rate capability for the half cell. Significantly, a Li-metal-free full battery is assembled successfully, with rGO/V₂O₅ hybrid sheets and lithiated graphite for cathodes and anodes, respectively. This full Li-ion battery exhibits a superior specific capacity of 213 mA h g⁻¹ at a current density of 100 mA g⁻¹ and a high specific energy density of 106.5 W h kg⁻¹ as a result. The good electrochemical performance suggests that this unique 2D hybrid material could be a promising candidate as a cathode material for lithium-ion batteries in the near future.