A brief overview of fuel cells

What is a fuel cell?

A fuel cell is a device that separates hydrogen electrons with a catalyst to produce electricity. After this process, the hydrogen combines with oxygen from the air to produce water and heat as by-products. In a sense, a fuel cell is like a battery, using chemical reactions -- not combustion -- to change energy stored in a fuel directly to electricity. Unlike a battery, a fuel cell can produce electricity continuously, without needing to be recharged, as long as it is supplied with hydrogen. When fuelled with pure hydrogen, a fuel cell emits no pollutants and no greenhouse gases. For more on the benefits of fuel cells.

How does it work?

The basic premise of a fuel cell is as follows: hydrogen (H2) flows toward one side of a catalyst-coated plate (such as one covered with platinum). When the hydrogen comes in contact with the catalyst plate, the proton slips through a plastic membrane. The hydrogen protons come in contact with oxygen in the air to form water (H2O).

The plastic membrane is too small for the hydrogen electrons to pass through. Instead, the electrons are collected on an external circuit and provide electricity.

Water and heat are the only by-products of this electricity-generation if pure hydrogen is being used.

Courtesy: World Fuel Cell Council

How did fuel cell technology develop?

Fuel cells were invented in 1839 by Sir William Grove, who initially called the device a gas battery, but were not practically used until 1932 by Francis Bacon, a chemical engineer at Cambridge University. In 1959 Bacon and his associates demonstrated a practical five-kilowatt fuel cell system. That same year, Harry Ihrig of Allis-Chalmers Manufacturing Company demonstrated the first fuel cell vehicle, a 20-horsepower fuel cell-powered tractor.

Fuel cells attracted the attention of the American space program, and in the 1960s, NASA began using fuel cells extensively. This led to extensive government research into fuel cells, mainly for the Gemini and Apollo space programs, and they are still used today in the space shuttle program.

Types of fuel cells

Benefits of fuel cells