Synthesis of Li3V2(PO4)3/reduced graphene oxide cathode material with high-rate capability

The Li₃V₂(PO₄)₃/reduced graphene oxide (LVP/rGO) composite is successfully synthesized by a conventional solid-state reaction with a high yield of 10 g, which is suitable for large-scale production. Its structure and physicochemical properties are investigated using X-ray diffraction, Raman spectra, field-emission scanning electron microscopy, transmission electron microscopy, and electrochemical methods. The rGO content is as low as ~3 wt%, and LVP particles are strongly adhered to the surface of the rGO layer and/or enwrapped into the rGO sheets, which can facilitate the fast charge transfer within the whole electrode and to the current collector. The galvanostatic charge–discharge tests show that the LVP/rGO electrode delivers an initial discharge capacity of 177 mAh g^?1 at 0.5 C with capacity retention of 88 % during the 50th cycle in a wide voltage range of 3.0–4.8 V. A superior rate capability is also achieved, e.g., exhibiting discharge capacities of 137 and 117 mAh g^?1 during the 50th cycle at high C rates of 2 and 5 C, respectively.