How do hydrogen-oxygen fuel cells produce electricity?

Hydrogen-oxygen fuel cells produce electricity through a chemical reaction between hydrogen and oxygen.

In a hydrogen-oxygen fuel cell, hydrogen and oxygen are used as fuel. The process begins with the introduction of hydrogen on the anode side and oxygen on the cathode side. The hydrogen molecules (H2) are split into two protons (H+) and two electrons (e-) at the anode. This process is facilitated by a catalyst, typically made of platinum.

The protons then pass through a proton exchange membrane (PEM), which only allows protons to pass through and blocks the electrons. This forces the electrons to travel through an external circuit, creating an electric current. This is the electricity that the fuel cell produces.

On the cathode side, oxygen molecules (O2) are introduced. The oxygen molecules react with the protons that have passed through the PEM and the electrons that have travelled through the external circuit to form water (H2O). This reaction also releases heat, which can be used for additional power.

The overall reaction in a hydrogen-oxygen fuel cell is 2H2 + O2 → 2H2O + heat + electricity. This reaction is clean, as the only by-products are water and heat. This makes hydrogen-oxygen fuel cells an attractive option for green energy production.

The efficiency of a hydrogen-oxygen fuel cell is also quite high, as it converts chemical energy directly into electrical energy without the need for combustion. This direct conversion avoids the losses associated with thermal energy conversion in traditional power plants. However, the challenge lies in the production, storage, and transportation of hydrogen, which currently limits the widespread use of hydrogen-oxygen fuel cells.