Polypyrrole-encapsulated vanadium pentoxide nanowires on a conductive substrate for electrode in aqueous rechargeable lithium battery

Abstract

Precursors of ammonium vanadium bronze (NH4V4O10) nanowires assembled on a conductive substrate were prepared by a hydrothermal method. After calcination at 360°C, the NH4V4O10 precursor transformed to vanadium pentoxide (V2O5) nanowires, which presented a high initial capacity of 135.0mAhg−1 at a current density of 50mAg−1 in 5M LiNO3 aqueous solution; while the specific capacity faded quickly over 50 cycles. By coating the surface of V2O5 nanowires with water-insoluble polypyrrole (PPy), the formed nanocomposite electrode exhibited a specific discharge capacity of 89.9mAhg−1 at 50mAg−1 (after 100 cycles). A V2O5@PPy //LiMn2O4 rechargeable lithium battery exhibited an initial discharge capacity of 95.2mAhg−1; and after 100 cycles, a specific discharge capacity of 81.5mAhg−1 could retain at 100mAg−1.