Alkaline Hydrogen-Iodine Fuel Cell

We have considered the acid-based Hydrogen-Iodine (H₂-I₂) fuel cell along with the acid-based Hydrogen-Bromine (H₂-Br₂) fuel cell as potential systems for electrical energy storage but decided to drop the H₂-I₂ system because of its low cell open circuit potential (0.54V), even though the H₂-I₂ system offers a major advantage of being a much more benign system than the H₂-Br₂ system because of the high corrosivity and toxicity of bromine.  Recently, we found that by operating the hydrogen reactions in an alkaline medium we could shift the electrode standard reduction potential from 0V to -0.83V which combined with the bromine electrode standard reduction potential of 1.09V increases the cell potential of an alkaline H₂-Br₂ fuel cell from 1.09V to 1.92V [1]. See Figure 1. 

This 0.83V shift in the hydrogen electrode potential motivated us to take another look at the alkaline H₂-I₂ system because of the higher cell potential (1.37V). See Figure 2. This presentation will discuss the alkaline H₂-I₂ system, its advantages and disadvantages, and recent results obtained by our group at the University of Kansas.