Why did space exploration encourage fuel cell research during the 1950s and 1960s?
The proton exchange membrane is one of the most advanced fuel cell designs. Hydrogen gas under pressure is forced through a catalyst, typically made of platinum, on the anode (negative) side of the fuel cell. At this catalyst, electrons are stripped from the hydrogen atoms and carried by an external electric circuit to the cathode (positive) side. The positively charged hydrogen ions (protons) then pass through the proton exchange membrane to the catalyst on the cathode side, where they react with oxygen and the electrons from the electric circuit to form water vapour (H2O) and heat. The electric circuit is used to do work, such as power a motor.
During the 1950s and 1960s, space exploration served as a primary catalyst for fuel cell research because of the urgent need for highly efficient, stable, and reliable power supplies for satellites and manned spacecraft.1
Fuel cells were particularly attractive for space missions for several key reasons:
- High Efficiency: Unlike internal-combustion engines, fuel cells convert chemical energy directly into electrical energy, achieving efficiencies as high as 60 percent. This high efficiency allowed for less fuel and smaller storage containers, which was critical for space travel.2
- Continuous Power: Unlike traditional batteries that require recharging, fuel cells can run continuously as long as they are supplied with fuel and an oxidizer.3
- Useful Byproducts: During missions such as Apollo and Gemini, these cells performed reliably and provided a vital secondary benefit: the production of drinkable fresh water.3
These advantages made fuel cells an ideal power source for space missions of limited duration, driving significant technological advancements in materials and electrode construction during that era.12