Master degree thesis studies polarisation of electrochemical processes on magnesium metal anode in MgCl2, Mg(TFSI)2, 1,3-dioxalane (DOL) and tetraethylen glycol dimethyl ether (TEGMDE) electrolyte solution. Effects of electrolyte concentration and separator thickness were studied using galvanostatic cycling (GCPL), electrochemical impedance spectroscopy (EIS) and galvanostatic electrochemical impedance spectroscopy (GEIS).
Despite Mg2+ concentration in electrolyte does not have essential effect on cell overpotential, we concluded, that dynamic impedance measurements are dependent on concentration of magnesium species, adsorbed to electrode surface. In experiments with changing separator thickness we were limited to high frequency GEIS measurements and chosen parameters of galvanostatic cycling were too short to detect difference between prepared cells. GEIS measurements also provided clues to uneven deposition of magnesium ions, which was proved with SEM imaging.
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