Greco, G.; Tatchev, D.; Hoell, A.; Krumrey, M.; Raoux, S.; Hahn, R.; Elia, G.: Influence of the electrode nano/microstructure on the electrochemical properties of graphite in aluminum batteries. Journal of Materials Chemistry A 6 (2018), p. 22673-22680
10.1039/c8ta08319c
Open Access Version
Abstract:
Herein we report on a detailed investigation of the irreversible capacity in the first cycle of pyrolytic graphite electrodes in aluminum batteries employing 1-ethyl-3-methylimidazolium chloride:aluminum trichloride (EMIMCl:AlCl3) as electrolyte. The reaction mechanism, involving the intercalation of AlCl4 in graphite, 3 has been fully characterized by correlating the micro/nano-modification to the electrochemical performance. To achieve this aim a combination of X-ray diffraction (XRD), small angle X-ray scattering (SAXS) and computed tomography (CT) has been used. The reported results evidence that the irreversibility is caused by a very large decrease in the porosity, which consequently leads to microstructural changes resulting in the trapping of ions in the graphite. A powerful characterization methodology is established, which can also be applied more generally to carbon-based energy-related materials.