A variety of alkali Fe(VI) oxide salts are explored for the first time as alkaline cathodes. The IR spectra and X-ray diffraction of these salts are compared to other known Fe(VI) spectra. Inductively coupled plasma and IR data indicate that the cesium salt is pure Cs2FeO4, whereas the rubidum and sodium salts consist of mixtures with potassium having the effective stoichiometric ratio Rb1.7K0.3FeO4 and Na1.1K0.9FeO4. Each of these salts exhibits a higher degree of solid-state stability. The measured solubility, S, of these salts is low in concentrated KOH electrolytes (millimolar solubility in 13.5 M KOH), decreasing as S(Na1.1K0.9FeO4) > S(K2FeO4) > S(Rb1.7K0.3FeO4) > S(Cs2FeO4). Each of the alkali cathodes are shown to sustain alkali current densities similar to a conventional MnO2 cathode. Alkaline zinc anode batteries were prepared and discharged with these alternative cathodes and exhibit high discharge energies, approaching but lower than those previously observed for potassium super-iron alkaline batteries. (C) 2004 The Electrochemical Society.