A high-rate, nanocomposite LiFePO4/carbon cathode

We describe here a new type of template-prepared nanostructured LiFePO4 electrode, a nanocomposite consisting of monodispersed nanofibers of the LiFePO4 electrode material mixed with an electronically conductive carbon matrix. This unique nanocomposite morphology allows these electrodes to deliver high capacity, even when discharged at the extreme rates necessary for many pulse-power applications. For example, this nanocomposite electrode delivers almost 100 % of its theoretical discharge capacity at the high discharge rate of 3 degrees C, and 36 % of its theoretical capacity at the enormous discharge rate of 65 degrees C. This new nanocomposite electrode shows such excellent rate capabilities because the nanofiber morphology mitigates the problem of slow Li+-transport in the solid state, and the conductive carbon matrix overcomes the inherently poor electronic conductivity of LiFePO4. (c) 2005 The Electrochemical Society. All rights reserved.