What is the difference between a fuel cell and a hydrogen internal combustion engine?

The main difference between a fuel cell and a hydrogen combustion engine is found in the process by which the hydrogen is used.

A fuel cell converts hydrogen and oxygen into electricity and water. This electricity can then be used to supply an electric motor which powers the vehicle.

The internal combustion engine principle involves mixing hydrogen with air in a combustion chamber and igniting it to create a controlled explosion. The explosion generates mechanical energy which is converted into motion, thereby propelling the vehicle.

The architecture of a hydrogen combustion engine is similar to that of a conventional combustion engine.