Synthesis of Li3V2(PO4)3 cathode material via a fast sol–gel method based on spontaneous chemical reactions

A fast sol–gel method based on spontaneous chemical reactions is developed to synthesize high performance Li3V2(PO4)3/C cathode material. The crystal structures, surface morphologies and electrochemical behaviors of the Li3V2(PO4)3/C samples sintered at different temperatures are investigated. In the potential range of 3.0–4.3 V, the sample sintered at 750 °C shows the highest discharge capacities of 127.9 mAh g−1 and 124.0 mAh g−1 at 1C and 5C rates after 100 cycles respectively. Furthermore, at 10C, 15C and 20C rates, the discharge capacities of the optimal Li3V2(PO4)3/C composite still retains 117.6 mAh g−1, 114.9 mAh g−1 and 83.6 mAh g−1 in the 150th cycle respectively. Cyclic voltammetry (CV) measurement illustrates that the electrochemical behavior of the optimal sample almost has no change after 100 cycles at 5C rate, indicating the stable structure of the synthesized material.

► A novel fast sol–gel method is developed to prepare Li3V2(PO4)3/C.
► Spontaneous chemical reactions among raw materials are utilized.
► Generated gas acts as a dispersant to mix raw material in atomic level.
► The synthesized material has a loose porous microstructure.
► High rate capability is obtained at 10C, 15C, and 20C rates (1C = 133 mA g−1).