Synthesis, characterization and electrochemical performance of Li2MnSiO4/C cathode material by solid-state reaction

Li2MnSiO4/C cathode material was synthesized by a traditional solid-state reaction method with Li2SiO3 and Mn(CH3COO)(2)center dot 4H(2)O as starting materials and sucrose as the carbon source. These materials were mixed and ground using a planetary miller and treated thermally at 800 degrees C for 12 h in an argon atmosphere. The heat treating procedure was estimated utilizing the thermogravimetric (TG) and differential scanning calorimeter (DSC) analysis. The prepared powder was consisted of majority of Li2MnSiO4 and minor impurities which were examined by X-ray diffraction (XRD). Field emission scanning electron microscopy (FESEM) morphology shown that the product of Li2MnSiO4/C has smaller particle size (about 30-80 nm), which is beneficial for Li-extraction/insertion kinetics. The initial charge capacity of the Li2MnSiO4/C electrode material obtained via solid-state reaction is 256 mAh/g (about 1.5 Li+ per unit formula extracted) and about 0.77 Li+ per unit formula is reversibly exchanged in the first cycle at a rate of C/16. (C) 2009 Elsevier B.V. All rights reserved.