Microwave synthesis of Li3V2(PO4)3/C as positive-electrode materials for rechargeable lithium batteries

The paper reports a microwave irradiation method to rapidly synthesize Li3V2(PO4)3/C materials as cathode for lithium ion batteries by the self-assembly microwave reaction oven with carbon seal reactor, using LiH2PO4, V2O5 and sucrose as raw materials. Sucrose was used to be reducer and carbon source. Thermogravimetric (TG) analysis, X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) were used to characterize its structure and morphology. Electrochemical properties of the Li3V2(PO4)3/C materials were studied by cyclic voltammetry (CV) and charge-discharge cycling performance. The results showed that the diffraction peaks of the sample correspond to a single-phase, and can be indexed as monoclinic structure with a space group of P21/n. An electrochemical test showed that Li3V2(PO4)3/C demonstrated an excellent electrochemical capacity of 138 mA h g−1 at 0.2 C rate and 124.1 mA h g−1 at 5 C rate with stable cycle ability.