A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent. Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used. Fuel cells are different from batteries in that they require a constant source of fuel and oxygen to run, but they can produce electricity continually for as long as these inputs are supplied.
See: History of Hydrogen Fuel Cell
Each cell is equivalent to 1.5 vdc. The more cells that you have in an stack the higher voltage potential.
You can easily learn about Hydrogen Fuel Cells with the help of experimental kits and learning aids. (Click here for)
Fuel cells may soon generate electrical power for all sorts of devices we use every day. “How Stuff Works” did an excellent article about hydrogen fuel cells.
The common source of hydrogen today is from petroleum (Oil) but it can be derived from water in a couple of other ways like chemical rapid oxidation, wind or solar electrolysis, using different electrolyte (s) or salt water (chlorine by product can be a problem).
Short explanation: The hydrogen fuel cell powers an electric motor.
GM “Hy-Wire” (video above) water powered car on the show: Top Gear. 4-min. into the video they display the hydrogen power plant that runs this vehicle’s propulsion system.