How do Hydrogen Fuel Cell Cars work? And how do they get refueled?
In: Engineering
Hydrogen fuel cell are relatively old technology. Similar fuel cells were used in the Apollo program to generate power onboard the command modules.
The fuel works by reacting hydrogen and oxygen producing water as waste.
Hydrogen atoms are positively charged while Oxygen atoms are negatively charged. The Oxygen atoms on one side of the fuel cell attract Hydrogen atoms pulling them through a membrane that strips them of their electrons. The electrons in turn produce the electric current. Meanwhile the atoms combine on the other side of the fuel cell producing water and completes the circuit by attracting the freed electrons through the electric system to the newly formed molecules.
Hydrogen fuel cell have about a 55% efficiency, and could be made more efficient by recycling the heat they produce into more electricity. They also only produce water as waste, which has it’s own potential environmental impacts but it is considerably better for the environment and easier to deal with than burning fossil fuels.
Fuel cells are recharged by refilling an onboard fuel tank with Hydrogen gas. While the Oxygen is drawn from our atmosphere.
The downside of the fuels cells is that they use a number of rare earth materials like Platinum which are expensive and difficult to mine.
Hydrogen gas is also difficult to make. Hydrogen is everywhere, since it’s a component of water. But current methods of separating Hydrogen and Oxygen from water like electrolysis of salt water requires a lot electricity making producing Hydrogen on a large scale impractical.
Hydrogen is also dangerously flammable, far more so than gasoline.
Latest Answers