A Li2FeSiO4/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 Li2FeSiO4 is greatly enhanced and the initial discharge capacity is ∼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 Li2FeSiO4 lattice. At high current densities, the Li2FeSiO4/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.