Lithium Insertion in Disordered Carbon−Hydrogen Alloys:  Intercalation vs Covalent Binding

Abstract

Disordered carbons obtained by pyrolyzing organic solids at T ≤ 700 °C retain substantial residual hydrogen and exhibit surprisingly large capacities for Li uptake in electrochemical cells. Using semiempirical computer simulations, we show that the high capacity is partially attributable to Li binding on H-terminated edges of hexagonal carbon fragments, with local geometries analogous to the stable isomer of the organolithium molecule C2H2Li2. These results can be tested experimentally by vibrational spectroscopy and have implications for further developments in Li-ion rechargeable battery technology.

Quantum chemical modeling of infrared and Raman activities in lithium-doped amorphous carbon nanostructures: hexa-peri-hexabenzocoronene as a model for hydrogen-rich carbon materials

“…The binding mechanism in hydrogen-rich carbon materials has been investigated by several authors at semiempirical and ab initio levels of theory [7,8]. The most sophisticate calculations were carried out recently on relatively small aromatic hydrocarbons [3].…”

Synthesis and Rate Performance of Monolithic Macroporous Carbon Electrodes for Lithium-Ion Secondary Batteries

“…For example, hydrogen-containing carbons have relatively large specific capacities (ca. 600± 1000 mA h g ±1 ), [33,61] although they exhibit poor cycling performance [34] and larger cycling hystereses. [35] They typically contain an atomic ratio of ca.…”

Lithium-ion batteries for hybrid electric vehicles and battery electric vehicles

“…In comparison to synthetic graphites, natural graphites show similar specific capacities and energy densities. However, natural graphites deliver poor lifetime behavior, especially poor calendar life stability (Prem Kumar et al, 2009;Patterson, 2009;Zheng et al, 1995;Papanak et al, 1996;Dahn et al, 1995).…”