Electrochemical Characteristics of Synthesized Nb 2 O 5 -Li 3 VO 4 Composites as Li Storage Materials

The increasing demand for energy storage in mobile electronic devices and electric vehicles has emphasized the importance of electrochemical energy storage devices such as Li-ion batteries (LIBs) and supercapacitors. For reversible Li storage, alternative anode materials are actively being developed. In this study, we designed and fabricated an Nb2O5-Li3VO4 composite for use as an anode material in LIBs and hybrid supercapacitors. Nb2O5 powders were dissolved into a solution and the precursors were precipitated onto Li3VO4 through a simple, low-temperature hydrothermal reaction. The annealing process yielded an Nb2O5-Li3VO4 composite that was characterized by X-ray diffraction, electron microscopy, and X-ray photoelectron spectroscopy. Electrochemical tests revealed that the Nb2O5-Li3VO4 composite electrode demonstrated increased capacities of approximately 350 and 140 mAh g-1 at 0.1 and 5 C, respectively, were maintained up to 1000 cycles. The reversible capacity and rate capability of the composite electrode were enhanced compared to those of pure Nb2O5-based electrodes. These results can be attributed to the microstructure design of the synthesized composite material.