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With a theoretically high capacity and suitable discharge/charge plateaus, lithium vanadates (such as Li 0.04 V 2 O 5 ) can be used as cathode material for lithium ion batteries. Herein, Li 0.04 V 2 O 5 nanowires are densely anchored onto reduced graphene oxide (rGO) nanosheets to form a Li 0.04 V 2 O 5 @rGO nanocomposite by a hydrothermal method with subsequent thermal treatment. Due to this unique structure, the Li 0.04 V 2 O 5 @rGO exhibits remarkable rate performance and excellent cycling stability. Specifically, it delivers a reversible discharge capacity of 738.09 mA h g −1 at a current density of 100 mA g −1 in the voltage range of 2.0–4.0 V. After 500 cycles, it still maintains a high capacity of 731.70 mA h g −1 , which represents 95.01% retention of the original reversible capacity. These results indicate that the Li 0.04 V 2 O 5 @rGO could be a promising candidate as cathode active material for long-term cycling performance in lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Precursors of ammonium vanadium bronze (NH 4 V 4 O 10 ) nanowires assembled on a conductive substrate were prepared by a hydrothermal method. After calcination at 360 °C, the NH 4 V 4 O 10 precursor transformed to vanadium pentoxide (V 2 O 5 ) nanowires, which presented a high initial capacity of 135.0 mA h g −1 at a current density of 50 mA g −1 in 5 M LiNO 3 aqueous solution; while the specific capacity faded quickly over 50 cycles. By coating the surface of V 2 O 5 nanowires with water-insoluble polypyrrole (PPy), the formed nanocomposite electrode exhibited a specific discharge capacity of 89.9 mA h g −1 at 50 mA g −1 (after 100 cycles). A V 2 O 5 @PPy //LiMn 2 O 4 rechargeable lithium battery exhibited an initial discharge capacity of 95.2 mA h g −1 ; and after 100 cycles, a specific discharge capacity of 81.5 mA h g −1 could retain at 100 mA g −1 . [ABSTRACT FROM AUTHOR]