While, magnesium is attractive for its potential to achieve a rechargeable battery, so far, reversible Mg plating has been achieved with only a narrow class of electrolytes, i.e., inorganic or organic magnesium aluminum chloride salts dissolved in ethereal solutions. For example, the Mg analogues to the most common commercial Li-ion electrolytes instantaneously decompose and passivate the Mg metal anode surface preventing further electrochemical reaction, consequently blocking the battery. The pursuit for a thermodynamically stable Mg electrolyte across a wide enough electrochemical window has been daunting. For example, LiBH₄/Mg(BH₄)₂, or [{(THF)₃MgCl}₂-μ-Cl]⁺[MCl_mR′_4-m]^? (M=Al, Mg; R′=alkyl, aryl, HMDS, where HMDS=N{Si(CH₃)₃}₂^?), generated from mixtures of Grignard reagents, or Mg(HMDS)₂, with AlCl_mR′_4-m or MgCl₂ in THF, contain electron-rich anions that are cathodically stable (unreactive toward Mg) and enable reversible Mg electrodeposition and dissolution on Mg metal anodes. However, these electron-rich anions are anodically stable only up to 3.3 V on inert electrodes such as Pt, or 2.2 V on stainless steel which is ubiquitously found in batteries due to Cl-promoted corrosion. Further improvement of anodic stability was achieved through the use of less electron-rich anions such as [B{OCH(CF₃)}₄]^?, [Al{OCH(CF₃)}₄]^?, and [CB₁₁H₁₂]^?. Mg(CB₁₁H₁₂)₂ is the current state of the art, with excellent cathodic stability as demonstrated in highly reversible Mg electrodeposition and dissolution as well as anodic stability of the electrolyte in glymes of up to 3.8 V and 4.6 V in sulfolane, yet the oxidation of [CB₁₁H₁₂]^? leads to passivation of electrodes. Thus far, these cathodically stable electrolytes are practically limited to electrochemical windows of <4.6 V.