Experimental procedures relating to the synthesis and the NMR measurements, along with single crystal x-ray diffraction information related to the electrolytes explored herein and to the reaction mixtures (pertaining to Scheme 1 below) appear in the experimental section of the Supporting Information (SI) file, see figures S1-S7. Ten equivalents of DME were added to a THF solution of precursor A and heated for 30 minutes at 50 o C to form a white precipitate. The solvents were evaporated from the reaction flask by vacuum to produce more precipitate. The white precipitate was then re-dissolved in fresh dry THF (scheme 1, path a), to form the solution referred to as electrolyte 1. Through slow vaporization of electrolyte 1, we obtained crystals of compound 1: [(DME . MgCl.3THF) + (Ph4Al) -]. The structure of compound 1 was confirmed by NMR spectroscopy (see figure and) and single crystal x-ray diffractometer (see figure ). The molecular structure of compound 1 comprises a MgCl + mono cation core which is coordinated by one DME molecule and three THF molecules and tetraphenyl aluminate counter anions (figure ).