The recent invention of rechargeable “modified” manganese oxide materials paves the way to the development of secondary batteries suitable for numerous applications. This includes alternatives to primary dry cells, and secondary lead/ acid and nickel‐cadmium batteries. Present results describe the performance of cells in which the modified materials are coupled with zinc and iron. As opposed to iron which does not affect the longevity and capacity retention of the modified electrodes, zinc has a pejorative effect on modified materials, owing to the formation of hetaerolite at the positive electrode. Methods to alleviate this effect and produce viable modified systems are described. At present, these systems retain about 50% of their theoretical one‐electron capacity even after two hundred fast charge‐discharge cycles.