Nanostructured Li3V2(PO4)3/C composite as high-rate and long-life cathode material for lithium ion batteries

Nanostructured Li3V2(PO4)3/C composite has been synthesized by a facile microemulsion method. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectra, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results confirm that the as-prepared Li3V2(PO4)3/C sample shows the pure monoclinic structure and nanosphere morphology. Li3V2(PO4)3/C has a particle size of about 100 nm, and these nanoparticles are connected each other by the conductive carbon network. Electrochemical measurements demonstratethat the Li3V2(PO4)3/C nanoparticles can deliver discharge capacities of 129.8, 126.1, 118.0, 116.1 and 110.1 mAh g−1 between 3.0 and 4.3 V, and 171.4, 163.1, 153.2, 144.0 and 133.4 mAh g−1 between 3.0 and 4.8 V at 1, 2, 5, 10 and 20 C, respectively. Even at 20 C rate, it still can present a reversible discharge capacity of 101.8 mAh g−1 with 92.5% capacity retention after 1400 cycles and 96.4 mAh g−1 with 72.3% capacity retention after 1000 cycles in the potential ranges of 3.0-4.3 V and 3.0-4.8 V, respectively. The excellent rate capability and long-term cycle performance demonstrate that the Li3V2(PO4)3/C nanoparticles prepared in this work has great potential for application as cathode materials in high-power lithium ion batteries.

Spheric Li3V2(PO4)3/C nanoparticles, which are fabricated by a facile microemulsion method, exhibit excellent rate capability and long cycle life over an extended 1000 cycles when evaluated as a cathode material for lithium ion batteries. These results are due to the nanoscale Li3V2(PO4)3 particles and conductive carbon network.Figure optionsDownload as PowerPoint slide