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arXiv · 1906.02986

Influence of the electrode nano/microstructure on the electrochemical properties of graphite in aluminum batteries

Giorgia Greco·Dragomir Tatchev·Armin Hoell·Michael Krumrey·Simone Raoux·Robert Hahn·Giuseppe Antonio Elia
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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, has been fully characterized by correlating the micro/nanostructural 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. Introduction

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Giorgia Greco, Dragomir Tatchev, Armin Hoell, Michael Krumrey, Simone Raoux, Robert Hahn, Giuseppe Antonio Elia. 2019-06-07. Influence of the electrode nano/microstructure on the electrochemical properties of graphite in aluminum batteries. https://doi.org/10.1039/c8ta08319c

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