Metal-air batteries use oxygen in the air as the battery's reactant. Compared with ordinary batteries,
metal-air batteries combine the characteristics of traditional dry batteries and fuel cells; they use
solid metals with higher activity, such as zinc, aluminum, magnesium, sodium and Lithium metal, etc. as
the anode, alkaline or neutral salt aqueous solution as the electrolyte, the cathode is the air diffusion
electrode, where air or oxygen enters, through the oxidation-reduction reaction, there is a potential
difference between the anode and the cathode to generate electricity. In other words, a metal-air
battery is a breathing battery. The oxygen in the air enters the battery and participates in the
electrochemical reaction on the cathode. During this process, the oxygen will be consumed. Therefore,
it is necessary to continuously obtain oxygen from the outside air. It can be obtained from the air in
the environment. Compared with other types of batteries, the energy cost of metal-air batteries is
relatively cheap. Also, because oxygen is supplied from the air and does not need to be stored in the
battery, the battery device can be lightweight, thereby increasing the scope of application .
