High capacity disordered carbons obtained from coconut shells as anode materials for lithium batteries

Carbonaceous materials have been obtained by the pyrolysis of coconut shells at 800 and 900 degrees C with pore forming substances such as KOH and ZnCl2. The prepared carbons were subjected to XRD, SEM, BET-surface area and charge-discharge studies. The structure and morphology were greatly changed by porogens, which in turn influence the electrochemical properties of the carbonaceous materials. Nanocrystalline tin (Sn) particles were prepared by chemical reduction method. The cycling tests showed that the addition of nanotin with the active material offers a stable cycling behavior. The electrochemical impedance spectra for the Li/C cells have been made and the results are discussed. (c) 2006 Elsevier B.V. All rights reserved.