The Aluminum-Air Power Source

The present section illustrates how calculations from basic thermodynamic data can lead to open-circuit cell potential in any condition of temperature and pressure. Chemical power sources, with the exception of fuel cells, are all based on the corrosion of a metal connected to the negative terminal. The aluminum-air power source, that owes its energy to the corrosion of aluminum in caustic, was chosen for this example because of the relative simple chemistry. 

The high electrochemical potential and low equivalent weight of aluminum combine to produce a theoretical energy density of 2.6 kWh/ kg and make it an attractive candidate as an anode material in metal/ 

The overall anodic reaction of the aluminum-air battery is the corrosion of aluminum into a soluble form stable in a caustic environment, AlO in Eq. (4.15), that can subsequently precipitate as Al O H O, as shown in Eq. (4.16), depending on the concentration of ions in solution, pH, and temperature. 

Equilibria Involving solid forms of oxidized aluminum 

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