Fuel cells generate electricity through a chemical reaction between hydrogen and oxygen. Hydrogen and ambient air are respectively supplied to the anode (negative electrode) and the cathode (positive electrode) of fuel cells to generate electricity.
Fuel cells consist of MEAs (membrane electrode assemblies) sandwiched between separators. An MEA is a solid polymer electrolyte membrane with catalyst layers applied. Since one cell can only yield less than one volt, several hundred cells are connected in a series to increase the voltage. This combined body of cells is called a fuel cell stack.
How electricity is generated from hydrogen and oxygen in a fuel cell
1. Hydrogen is supplied to the anode side.
2. Hydrogen molecules activated by the anode catalyst release their electrons.
3. The released electrons travel from the anode to the cathode, creating an electrical current.
4. The hydrogen molecules that release electrons become hydrogen ions and move through the polymer electrolyte membrane to the cathode side.
5. The hydrogen ions bond with airborne oxygen and electrons on the cathode catalyst to form water.
Here are some of the key specifications of Toyota's proprietary FC Stack.