Energy storage studies on InVO4 as high performance anode material for Li-ion batteries

InVO4 has attracted much attention as an anode material due to its high theoretical capacity. However, the effect of preparation methods and conditions on morphology and energy storage characteristic has not been extensively investigated and will be explored in this project. InVO4 anode material was prepared using five different preparation methods: solid state, urea combustion, precipitation, ball-milling, and polymer precursor methods. Morphology and physical properties of InVO4 were then analyzed using X-ray diffraction (XRD), scanning electron microscope (SEM), and Brunauer-Emmett-Teller (BET) surface area method. XRD patterns showed that orthorhombic phased InVO4 was synthesized. Small amounts of impurities were observed in methods II, III, and V using XRD patterns. BET surface area ranged from 0.49 to 9.28 m(2) g(-1). SEM images showed slight differences in the InVO4 nanosized crystalline structures with respect to preparation methods and conditions. Energy storage studies showed that, among all the preparation methods, the urea combustion method produced the best electrochemical results, with negligible capacity fading between the 2nd and 50th cycles and high capacity of 1241 mA h g(-1) at the end of the 20th cycle, close to the theoretical capacity value. Precipitation method also showed good performance, with capacity fading (14%) and capacity of 1002 mA h g(-1) at the 20th cycle. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) was then used to determine the reaction mechanisms of InVO4.