Vertical aligned V2O5 nanoneedle arrays grown on Ti substrate as binder-free cathode for lithium-ion batteries

V2O5 nanoneedle arrays were grown directly on titanium (Ti) substrate by a facile solvothermal route followed with calcination at 350 °C for 2 h. The as-prepared V2O5 nanoneedles are about 50 nm in diameter and 800 nm in length. The electrochemical behavior of V2O5 nanoarrays as binder-free cathode for lithium-ion batteries (LIBs) was evaluated by cyclic voltammetry and galvanostatic discharge/charge tests. Compared with V2O5 powder electrode, V2O5 nanoneedle arrays electrode exhibited improved electrochemical performance in terms of high discharge capacity of 262.5 mA h g−1 between 2.0 and 4.0 V at 0.2 C, and high capacity retention up to 77.1% after 100 cycles. Under a high current rate of 2 C, a discharge capacity of about 175.6 mA h g−1 can be maintained. The enhanced performance are mainly due to the intimate contact between V2O5 nanoneedle active material and current collector, which enable shortened electron transfer pathway and improved charge transfer kinetics, demonstrating their potential applications in high rate electrochemical storage devices.