Hexafluorophosphate-Based Solutions for Mg Batteries and the Importance of Chlorides.

The selection of viable conventional magnesium salts in electrolyte solutions for Mg secondary batteries is very limited. Reversible magnesium deposition was demonstrated with only MgTFSI, in ethereal solutions. A recent report has suggested that Mg can be reversibly deposited from a solution of Mg(PF) in tetrahydrofuran and acetonitrile.

The High Performance of Crystal Water Containing Manganese Birnessite Cathodes for Magnesium Batteries.

Rechargeable magnesium batteries have lately received great attention for large-scale energy storage systems due to their high volumetric capacities, low materials cost, and safe characteristic. However, the bivalency of Mg(2+) ions has made it challenging to find cathode materials operating at high voltages with decent (de)intercalation kinetics. In an effort to overcome this challenge, we adopt an unconventional approach of engaging crystal water in the layered structure of Birnessite MnO2 because the crystal water can effectively screen electrostatic interactions between Mg(2+) ions and the host anions.

Novel, electrolyte solutions comprising fully inorganic salts with high anodic stability for rechargeable magnesium batteries.

Herein the first inorganic magnesium salt solution capable of highly reversible magnesium electrodeposition is presented. Synthesized by acid-base reaction of MgCl2 and Lewis acidic compounds such as AlCl3, this salt class demonstrates upwards of 99% Coulombic efficiency, deposition overpotential of <200 mV, and anodic stability of 3.1 V.