How a Fuel Cell works

Q. What is a fuel cell?

A. A fuel cell is a device that generates electricity from a continuing chemical reaction. The principle of the fuel cell was discovered by Christian Friedrich Schonbein in 1838, and the first working fuel cell was developed by Welsh scientist Sir William Robert Grove in 1843. Fuel cells were used on the Apollo spaceflight missions to the moon, combining hydrogen and oxygen to provide electricity and drinking water to astronauts. Since that time, they have become the focus of development for stationary and portable power generation systems, and fuel-cell-powered electric vehicles.

Q. How does a hydrogen fuel cell work?

A. While there are different kinds of fuel cells, a Proton Exchange Membrane (PEM) hydrogen fuel cell harnesses the electricity that is created when a chemical reaction occurs between hydrogen and oxygen. When hydrogen is introduced on the anode (negative) side of the fuel cell, it interacts with a metal catalyst to form two hydrogen ions (+) and two electrons (-). The electrons are conducted away to form an electric current. The positively charged hydrogen ions pass into the film-like Proton Exchange Membrane, where they meet with oxygen atoms from the cathode to form water vapor molecules (H2O) – the only exhaust product other than heat. The entire reaction continues to produce electricity and water vapor as long as hydrogen and oxygen are available to the Proton Exchange Membrane and its catalysts. See diagram

Q. How is a fuel cell different than a battery?

A. They are similar in concept but very different in operation. Batteries store electrical energy chemically in a closed system and must be recharged or replaced. In a fuel cell such as Trulite’s, hydrogen flows into the fuel cell which is converted to electricity.