Abstract: A process method for producing a lithium based mixed oxide of the formula LiM′x . . . Oy through the steps of combining a lithium oxide with a second oxide having the base metal element (M′) at room temperature; and applying to the combination, a high energy milling process, wherein the high energy milling process obtains, without the addition of substantial external heat being added to the synthesis, a chemical synthesis of a composite oxide of the above formula, having crystallites of nanometer dimension.