A novel Li(2)FeSiO(4)/C composite: Synthesis, characterization and high storage capacity

A Li(2)FeSiO(4)/C composite material has been prepared via a solution-polymerization approach. The composite is characterized by X-ray diffraction (XRD), X-ray absorption near edge structure (XANES), scanning electron microscope (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and superconducting quantum interference device (SQUID). The electrochemical performance of the Li(2)FeSiO(4) is greatly enhanced and the initial discharge capacity is similar to 220 mA h g(-1), when it is cycled between 1.5-4.8 V. This indicates that more than one lithium ion can be extracted out of the Li(2)FeSiO(4) lattice. At high current densities, the Li(2)FeSiO(4)/C also exhibits excellent rate capability and cycling stability. This indicates that it is a very promising cathode material for next generation lithium-ion batteries.National Natural Science Foundation of China[20873115, 20473068, 29925310]; National Basic Research Program[2007CB209702, 2011CB905903