Partially-crystallized carbon material obtained by the reducing reactions from alkalis carbonate and its electric performance

We report here a new sort of partially-crystallized carbon materials obtained from the reducing reactions between alkalis carbonate (M2CO3 M=Li, K, Na) and active metals such as Li, Mg, Al and Ga. The chemical reactions are carried out at the temperature range of 600-900 degrees C and under the argon ambience. The typical reaction can be represented as follows:K2CO3 +4Li=2Li(2)O+K2O+C. X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and energy-dispersive X-ray fluorescence (EDAX) characterizations reveal evidently that the obtained final black powder products are carbon materials with partially-crystallized structure. In addition, we also investigate the electric performance of the obtained carbon materials, the initial discharge capacity and initial charge capacity have been measured respectively as high as 1267 mAh/g and 736 mAh/g. (c) 2007 Elsevier B.V. All rights reserved.