The fuel cell is a key technology for the use of hydrogen as a clean energy source – whether in cars, trains, buildings or industry. But how exactly does a fuel cell work? In this article, we explain how it works and the advantages of this fascinating technology.
Basic principle: electricity from hydrogen and oxygen
A fuel cell converts the chemical energy of hydrogen directly into electrical energy – without combustion, almost silently and without harmful emissions. The only “waste product” is
Structure and function of a fuel cell
A single fuel cell essentially consists of three components:
- Anode (negative pole)
- Cathode (positive pole)
- Electrolyte membrane separating the two sides
This is how the process works:
- Supply of hydrogen: Hydrogen gas (H₂) is supplied at the anode. There, catalysts split the hydrogen molecules into protons (H⁺) and electrons (e-).
- Separation of protons and electrons:
- The protons migrate through the electrolyte membrane to the cathode.
- The electrons cannot pass through the membrane – instead they flow via an external circuit to the cathode, generating an electric current.
- Reaction with oxygen: The electrons, protons and the oxygen (O₂) supplied from the air come together again at the cathode. Water (H₂O) is produced – in the form of water vapor.
Types of fuel cells
There are different types of fuel cells, depending on the application and the technology used:
- PEM fuel cell (Proton Exchange Membrane): Frequently used in vehicles and for mobile applications. It works at low temperatures and reacts quickly to load changes.
- SOFC (Solid Oxide Fuel Cell): High-temperature fuel cell, particularly efficient for stationary applications such as power plants or building supply.
- AFC, MCFC, PAFC: Other types with special areas of application, e.g. in aerospace or industry.
Advantages of fuel cell technology
- Zero emissions: Only water vapor is produced – no CO₂, particulate matter or NOx emissions.
- High efficiency: Significantly more efficient than classic combustion engines.
- Quiet operation: No moving parts such as pistons or turbines.
- Versatility: Suitable for vehicles, buildings, emergency power supply and industrial applications.
Conclusion
The fuel cell enables the direct use of hydrogen – efficiently, quietly and emission-free. This makes it one of the key technologies for the energy transition and for a climate-friendly future.
