Ti influence on the electrochemical performance of Li3V2 (PO4)3 cathode materials synthesized by a sol-gel method

Abstract

Li3V2(PO4)3/C and Li3V2-xTix (PO4)3/C (x=0.03, 0.05, 0.07) cathode materials are synthesized by a solid-state method and a sol-gel method, respectively. X-ray diffraction (XRD) and scanning electronic microscopic (SEM) are employed to characterize the structures and morphologies of the as-prepared samples. The XRD patterns show that Ti-doping does not alter the monoclinic structure of Li3V2 (PO4)3 and does not create a new phase as well. The SEM images show that Ti-doping can prevent the aggregations of the fine grains compared with the pure Li3V2 (PO4)3/C. The electrochemical measurements show that Ti doping can improve the cycling and rate performance of LVP/C composite. The improved electrochemical properties of the Li3V2-xTix (PO4)3/C cathode materials may be attributed to the enhanced ionic and electronic conductivities caused by Ti doping.