Fuel cells have long been considered to be the most likely alternative to conventional engines because they provide both ultralow emissions and high efficiencies. Unlike batteries, fuel cells do not require charging and do not lose energy when converting between electrical and chemical energy. Indeed, energy storage in some form of fuel is more effective than in any type of rechargeable battery, since it improves the power density of the system and ultimately the driving range of the vehicle.
However, fuel cells have yet to be commercialized for more general applications, such as stationary power plants and transportation. But many people now believe that these applications will become a commercial reality in the next five to ten years, mainly due to technological improvements in the so-called proton-exchange membrane (PEM) fuel cell. These advances have also led to a series of strategic alliances between fuel-cell developers and car manufacturers.
In the August issue of Physics World magazine (information), Gregor Hoogers from the Johnson Matthey Technology Centre, Reading, UK, describes the latest advances in this promising technology.