Novel low-temperature synthesis and characterization of LiNiVO4 forhigh-voltage Li ion batteries

Abstract

A novel high-voltage cathode material, LiNiVO ₄ , with an inverse spinel structure, space group, Fdm (O _h ⁷ ) has been synthesized at temperatures as low as 320 °C using the aqueous glycine–nitrate combustion process. The phase purity of the synthesized product has been found to be excellent as confirmed by X-ray diffraction and Raman spectroscopy. The physical grain size has been determined from SEM analysis. EDAX measurements indicate the presence of nickel and vanadium at the stoichiometric level. Thermal studies of the precursor show evidence for the phase formation and/or crystallization of the inverse spinel compound. The electrochemical behaviour of this compound, which is used as a positive electrode in lithium batteries, exhibits a high voltage of 4.8 V vs. Li and has been assessed by slow scan cyclic voltammetry in 2450 coin-type electrochemical test cells including a Li metal anode or a carbonaceous anode as well as a high voltage resistant organic non-aqueous mixed electrolyte. The cyclic voltammograms show excellent reversibility of the compound, proving its redox kinetics in lithium-containing rechargeable cells.