Alkaline fuel cell

The alkaline fuel cell (AFC), also known as the Bacon fuel cell after its British inventor, Francis Thomas Bacon, is one of the most developed fuel cell technologies. NASA has used alkaline fuel cells since the mid-1960s, in Apollo-series missions and on the Space Shuttle. Alkaline fuel cells consume hydrogen and pure oxygen producing potable water, heat, and electricity. They are among the most efficient fuel cells, having the potential to reach 70%.

The fuel cell produces power through a redox reaction between hydrogen and oxygen. At the anode, hydrogen is oxidized according to the reaction:

${\displaystyle \mathrm {2H} _{2}+\mathrm {4OH} ^{-}\longrightarrow \mathrm {4H} _{2}\mathrm {O} +\mathrm {4e} ^{-}}$

producing water and releasing electrons. The electrons flow through an external circuit and return to the cathode, reducing oxygen in the reaction:

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