V2O5 nanoparticles confined in Three-Dimensionally organized, porous Nitrogen-Doped graphene frameworks: Flexible and Free-Standing cathodes for high performance lithium storage

Nowadays, lithium-ion batteries (LIBs) are attracting great interest for energy storage applications ranging from small-size cell phones to large-size electric vehicles. Among different cathode materials which have been widely investigated, vanadium pentoxide (V2O5) is particularly attractive because of its high specific capacity and low cost. However, drawbacks such as low electronic conductivity and poor ion diffusion kinetics restrict its further applications in large-size electric vehicles. In this work, we report a one-step hydrothermal strategy to integrate nitrogen doping, aerogel formation and V2O5 loading on graphene nanosheets simultaneously. The introduction of 3D nitrogen-doped graphene (3DNG) can provide higher electronic conductivity and Li+ ion diffusion kinetics. The resulting V2O5@3DNG aerogels can be used as cathodes directly without any binders, conductive additives and metallic collectors. The free-standing and flexible cathodes can effectively promote rapid capacity response and buffer the stress generated during the high-rate charging/discharging processes, which are responsible for superior cyclability and rate capabilities. This strategy may provide new insight into the improvements of LIB performances. (C) 2018 Elsevier Ltd. All rights reserved.