In recent years there has been a growing trend towards the development of environmentally friendly technologies. Combustion and gasoline engines, will soon become things of the past with the emergence of newer, more efficient sources of power. Such advancements come through the development, and constant improvements of fuel cells.

A fuel cell is an electrochemical device capable of converting hydrogen and oxygen into electricity and heat. Much like a battery that is can be recharged while power is being drawn from it. However instead of recharging electricity it uses hydrogen and oxygen.

One of the more common types of fuel cells is known as the PEM fuel cell, or the Proton Exchange Membrane Fuel Cell. Which uses one of the simplest reactions of all other fuel cells.

As you can see there are four major components:

• The Anode: the negative post of the fuel cell.
• The Cathode: the positive post of the fuel cell.
• The Electrolyte: this conducts positively charged ions.
• The Catalyst: this facilitates the reaction of oxygen and hydrogen.

There are actually several reactions taking place at the same time. One the anode side of the fuel cell pressurized hydrogen gas [H₂] is forced through the catalyst. When an H₂ comes into contact with the catalyst it splits into two H⁺ ions and two e^- electrons. The electrons will then make their way through the anode, and into the external circuit, to generate power, then finally they travel to the cathode side of the fuel cell.

At the same time on the cathode side of the cell, oxygen [O₂] gas is also going through much the same process. Contact with the catalyst causes it to form two oxygen atoms. Each with a very strong negative charge; It is this negative charge that attracts the positively charged H⁺ ions through the membrane where they then combine to form water [H₂O] molecule.

How effective is this reaction?

In general this reaction in a single fuel cell will only produce about 0.7 volts. To get this value up to reasonable levels many separate fuel cells must be combine to from a fuel stack. (Viewed below) Today A fuel cell this size is capable of powering a car.