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

Abstract

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.