Rate performance of Li3V2(PO4)3/C cathode material and its Li+ ion intercalation behavior

Rate performance and kinetic properties of Li3V2(PO4)3/C composite electrode have been investigated in this paper. The Li3V2(PO4)3/C composite obtained via a rheological phase method displays a monoclinic structure with an average particle size of ca. 200–300 nm. Electrochemical tests show this material exhibits good reversibility and excellent rate capability up to a current density of 3373 mA g−1 (30 C). The composite material achieves its theoretical capacity at 1 C rate. The capacity loss is less than 4% from 1 to 10 C. Even at the highest 30 C rate, the capacity is above 100 mAh g−1. The kinetic properties of the composite electrode are analyzed by cyclic voltammetry (CV) and potentiostatic intermittent titration (PITT) techniques. The Li+ ion diffusion coefficients calculated from PITT are in the range of 10−7–10−8 cm2 s−1.

► The Li3V2(PO4)3/C composite prepared via a facile rheological phase method exhibited good reversibility and excellent rate capability at various current densities (1–30 C). ► Li+ ion diffusion behavior was carefully studied by CV and PITT. The results of PITT gave a panoramic view of the Li+ ion diffusion coefficients. ► This material is hopeful for application in high-power devices.