a stabilized electrode comprising a metal oxide or lithium - metal - oxide electrode material is formed by contacting a surface of the electrode material , prior to cell assembly , with an aqueous or a non - aqueous acid solution having a ph greater than 4 but less than 7 and containing a stabilizing salt , to etch the surface of the electrode material and introduce stabilizing anions and cations from the salt into said surface . the structure of the bulk of the electrode material remains unchanged during the acid treatment . the stabilizing salt comprises fluoride and at least one cationic material selected from the group consisting of ammonium , phosphorus , titanium , silicon , zirconium , aluminum , and boron .