Synthesis and rate performance of lithium vanadium phosphate as cathode material for Li-ion batteries

A sphere-like carbon-coated Li3V2(PO4)3 composite was synthesized by carbothermal reduction method with two sessions of ball milling followed by spray-drying with the dispersant of polyethylene glycol added. The structure, particle size, and surface morphology of the cathode material were investigated via X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy. Results indicate that the Li3V2(PO4)3/C composite has a sphere-like morphology composed of a large number of carbon-coated ultrafine particles linked together with a monoclinic structure. In the voltage range of 3.0–4.3 V, it exhibits the discharge capacities of 130 mAh g−1 and 100 mAh g−1 at 0.2 C and 20 C rates, respectively. This behavior indicates that the obtained Li3V2(PO4)3/C material has excellent rate capability.

Research highlights► The Li3V2(PO4)3/C composite is sphere-like with carbon-coated. ► The composite containing large amount of ultrafine particles linked together. ► The synthesis method is two-session-ball-milling-assisted spray-drying. ► The discharge capacity is 100 mAh g−1 at 20 C rate in the voltage range of 3.0–4.3 V.