Magnesium batteries are one of the best candidates for the next generation of batteries. The biggest challenge in their development is the lack of suitable electrolytes that allow reversible deposition and stripping of magnesium. In this thesis, we compared the behaviour of electrochemical cells using electrolytes of different generations in combination with Mg metal anode and stainless steel working electrode. Electrolyte with Grignard reagent, more precisely combination of PhMgCl and AlCl3, was chosen as the representative of the 1st generation of Mg electrolytes, Mg(TFSI)2 and MgCl2 in different ratios (1:1, 1:0,5) dissolved in DGM for the 2nd generation electrolytes and Mg(Al(hfip)4)2 and Mg(B(hfip)4)2 also dissolved in DGM for the preparation of 3rd generation of electrolytes. We compared their Coulombic efficiencies of stripping and deposition of Mg, overvoltage, morphology of deposits and elementary composition. Of all tested electrolytes, 0,4 M APC in THF was found to have the highest average Coulombic efficiency (> 99 %) and 0,4 M Mg(B(hfip)4)2 in DGM the lowest overvoltage (< 0,08 V). Second generation electrolytes showed the lowest average Coulombic efficiency (< 90 %) and highest overpotentials (> 0,27 V). 0,4 M Mg(Al(hfip)4)2 in DGM showed the best ratio between high Coulombic efficiency (> 98 %) and low overvoltage (< 0,1 V). Using a scanning electron microscope, we observed hexagonal deposits at 50.000x magnification, that changed into clusters of various shapes and sizes with further deposition. EDS characterization of electrodes confirmed that the deposits on the working electrode are in fact metallic magnesium.
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