Composites of LiMnPO4 with Li3V2(PO4)3 for cathode in lithium-ion battery

A series of xLiMnPO4·yLi3V2(PO4)3/C (x/y = 8:1, 4:1, 2:1, 1:1) composites have been successfully synthesized by spray drying followed by solid-state reaction. The morphology and crystalline structure are characterized by scanning electron microscope, transmission electron microscopy, energy dispersive spectroscopy and X-ray diffraction. The composites contain both LiMnPO4 and Li3V2(PO4)3 phases with nanosized dispersion, and Mn doping LVP and V doping LMP also coexist. The incorporation of Li3V2(PO4)3 with LiMnPO4 can effectively enhance electrochemical kinetics of LiMnPO4 phase via the structure modification and shortened Li-diffusion length in the LiMnPO4. Among these composites, 2LiMnPO4·Li3V2(PO4)3/C composite delivers a discharge capacity of 148 mAh g−1 at 0.1 C rate, against 105 mAh g−1 for the pristine LiMnPO4/C, and exhibits much better high/low-temperature performances than the latter.