Facile Synthesis and Electrochemical Analysis of Zn-Doped V2O5 Anode Materials for High-Rate Li Storage

Abstract

The surging demand for Li rechargeable batteries with high energy densities and rapid rate capability has propelled research on materials that can replace the conventional anode materials like graphite. Vanadium pentoxides (V2O5) have emerged as promising anode candidates owing to their excellent rate capability. Specifically, V2O5 allows the electrochemical prelithiation process, in which three Li-ions can be inserted to form Li3V2O5, followed by reversible insertion and extraction of two Li-ions. Nevertheless, the unsatisfactory Li-ion diffusion coefficients and electrical conductivities of these materials remain major drawbacks. Here, we propose a Zn-doped V2O5 anode, fabricated using a two-step sol–gel method, for high-rate Li-ion batteries. Zn was incorporated into V2O5 to enhance the Li-ion transport kinetics through the electrode. The crystal structure (orthorhombic) of Zn-doped V2O5 was identified by X-ray diffraction analysis, and the Zn doping was confirmed by X-ray photoelectron microscopy. The effect of Zn doping was thoroughly examined using various analytical methods, such as cyclic voltammetry and galvanostatic intermittent titration technique. The Zn-doped V2O5 electrode exhibited remarkable cycling durability, enduring for 1000 cycles, while retaining an enhanced capacity, even under a high rate of 2C.