Novel carbons from nanocomposites for high lithium storage

Abstract

Carbons obtained by the pyrolysis of Taeniolite/Indoine blue and Taeniolite/Safranine nanocomposites were investigated for the lithium storage in Li/carbon cells. A high reversible capacity (900 mA h/g) was found, especially for carbons prepared at 700°C. The mesoporous character due to the oxidation of the interlayer carbon by the neighbour SiO 4 tetrahedra during the pyrolysis is responsible for the important insertion of lithium and for the capacitive properties (90 F/g). The high polarisation between insertion and extraction of lithium is strictly connected with these properties. For comparison, carbons reduced with hydrogen and obtained from the pure precursor (Indoine blue) were investigated to elucidate the role of heteroatoms. Voltammetry experiments proved that insertion of lithium is kinetically limited.