Novel carbons from nanocomposites for high lithium storage

Carbons obtained by the pyrolysis of Taeniolite/Indoine blue and Taeniolite /Safranine nanocomposites were investigated for the lithium storage in Li/c arbon cells. A high reversible capacity (900 mA h/g) was found, especially for carbons prepared at 700 degrees C. The mesoporous character due to the oxidation of the interlayer carbon by the neighbour SiO4 tetrahedra during the pyrolysis is responsible for the important insertion of lithium and for the capacitive properties (90 F/g). The high polarisation between insertio n and extraction of lithium is strictly connected with these properties. Fo r comparison, carbons reduced with hydrogen and obtained from the pure prec ursor (Indoine blue) were investigated to elucidate the role of heteroatoms . Voltammetry experiments proved that insertion of lithium is kinetically l imited. (C) 1999 Elsevier Science S.A. All rights reserved.