Boron containing electrolytes and methods of forming boron containing electrolytes for magnesium batteries

A method of forming an electrolyte includes combining a magnesium closo-borate-organic solvent salt with an organic cation-anion salt, and removing the organic solvent from the magnesium closo-borate-organic solvent salt and to form an electrolyte comprising a magnesium closo-borate salt/organic cation-anion salt mixture. The magnesium closo-borate salt can have the structure Mg(CBHX)where: y is 0 or 1; a is 10 or 12; z is 0 to a; and X is independently halogen, alkyl, alkoxy, acyl, aryl, alkylaryl, arylalkyl, and/or aryloxy substituents and wherein alkyl groups can be linear, branched, or cyclic. Also, any of the substituents can be partially or fully halogenated.