Synthesis of LiFe(1−x)V x PO4/C composite cathode materials with high performance via an aqueous solution–evaporation method

The modification techniques of applying carbon coating on particle surface and doping vanadium at Fe site were applied to make the LiFePO4 cathode materials achieve high rate performance in lithium ion batteries. To design and synthesize these LiFe(1−x)V x PO4/C (x = 0, 0.02, 0.05, or 0.08) composites, an aqueous solution–evaporation method was taken, in which every kind of raw material was distributed at a high degree of uniformity. The LiFe0.95V0.05PO4/2.57 wt% C composite displayed the best electrochemical performances. At rates of 0.1, 0.5, 2, 5, and 10 C (1 C = 170 mAg−1), it delivered a discharge capacity of 157.8, 156.9, 149, 139.6, and 130.1 mAh g−1, respectively. The composite exhibited perfect cycle stabilities as well, maintaining 100 % (0.5 C), 99.7 % (2 C), 98.9 % (5 C), and 96.6 % (10 C) of the first discharge capacity after 100 cycles at different rates, respectively.