Metal-air batteries, such as Al-air, Zn-air, Mg-air are a novel green energy storage devices, which overcome the limitations of hydrogen technology and Li-ion batteries in replacing fossil fuels. Using mainly chronopotentiometry and impedance spectroscopy techniques in a three-electrode system, the emphasis was on testing 171 cathode prototypes to develop a state-of-art cathode. The developed cathodes were used in a full-sized...