Elia, G.A.G.A.EliaHasa, I.I.HasaGreco, G.G.GrecoDiemant, T.T.DiemantMarquardt, K.K.MarquardtHoeppner, K.K.HoeppnerBehm, R.J.R.J.BehmHoell, A.A.HoellPasserini, S.S.PasseriniHahn, R.R.Hahn2022-03-052022-03-052017https://publica.fraunhofer.de/handle/publica/25191010.1039/c7ta01018dHerein we report a novel study on the reaction mechanism of non-aqueous aluminum/graphite cell chemistry employing 1-ethyl-3-methylimidazolium chloride: aluminum trichloride (EMIMCl:AlCl3) as the electrolyte. This work highlights new insights into the reversibility of the anion intercalation chemistry besides confirming its outstanding cycle life exceeding 2000 cycles, corresponding to more than 5 months of cycling test. The reaction mechanism, involving the intercalation of AlCl4- in graphite, has been fully characterized by means of ex situ X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray absorption near edge structure spectroscopy (XANES) and small-angle X-ray scattering (SAXS), evidencing the accumulation of anionic species into the cathode as the main factor responsible for the slight initial irreversibility of the electrochemical process.en621541journal article