The Iron/Air is another of the air-electrode
batteries. The electrochemistry is as follows:
Half Reaction
Voltage
O2 + 2Fe +2H2O=2Fe(OH)2
O2 +2H2O +2e=H2O2 +2(OH)
These batteries require a high degree of
support, since the CO2 must be taken out of the air in order to
prevent potassium carbonates forming in the KOH electrolyte. They have been
built in large backup systems. The air electrode consists of a catalyst on a
support. For example a carbon particle substrate held together with Teflon,
coated with a silver complex catalyst. Support is provided by a silver-plated
nickel screen.
