Disclosed herein is a method comprising reacting a metal borohydride with a metal chloride composition that comprises magnesium chloride in a solvent to form a reaction mixture; wherein either the metal borohydride, the metal chloride composition or both the metal borohydride and the metal chloride composition are soluble in the solvent and a formed metal chloride is insoluble in the solvent; removing the solvent from the reaction mixture to produce a borohydride complex; treating the borohydride complex to obtain magnesium borohydride; extracting magnesium borohydride solvate; and desolvating the magnesium borohydride solvate to form magnesium borohydride.