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How do fuel cells generate electricity from hydrogen and oxygen?

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Crystal growth — electrochemical reaction Different mechanisms of crystal growth.

Fuel cells generate electricity through an electrochemical reaction that converts chemical energy directly into electrical energy. A fuel cell consists of two electrodes—an anode and a cathode—separated by an electrolyte that conducts ions.12

The process functions as follows:
* At the Anode: Hydrogen fuel is supplied to the anode, where it is oxidized. This reaction produces hydrogen ions and releases electrons.1
* Electron Flow: The released electrons travel through an external circuit to the cathode, creating an electric current.1
* At the Cathode: Oxygen is supplied to the cathode. The hydrogen ions move through the electrolyte to the cathode, where they combine with the oxygen and the incoming electrons to produce water as the primary byproduct.1

Unlike batteries, fuel cells do not deplete their internal components; they continue to produce power as long as they are supplied with fuel and an oxidizer.12