I need a definition about fuel cell it's operation.Also explain about installing fuel cell in vehicle.
Most hydrogen cars use proton exchange membrane (PEM) fuel cells arranged in fuel cell stacks. These fuel cells take in compressed hydrogen and oxygen from the air and create electricity to drive the electric motors of a hydrogen car. Hydrogen is channeled through the anode side of the fuel cell, while oxygen is channel through the cathode side. At the anode side, the catalyst, which is usually platinum, causes the hydrogen to split into protons and electrons. The PEM membrane only allows the protons (positively charged ions) to pass through to the cathode. The electrons (negatively charged ions) pass along an external route to the cathode, which creates an electrical current. At the cathode, the hydrogen protons, electrons and oxygen unite to form water, which flows out the fuel cell as the only byproduct. A fuel cell in some hydrogen cars is installed underneath the hood while in other cars it’s underneath the floor panel in a “sandwich” design. Since the hydrogen is already compressed no compressor is needed for this, but most cars have a compressor to blow air (oxygen) through the fuel cell. Electricity from the fuel cell goes to one of the electric driver motors which may be one, two or four for all-wheel drive depending upon how the vehicle is configured.
A fuel cell is an electrochemical energy conversion device. Fuel cells differ from batteries in that they are designed for continuous replenishment of the reactants consumed; they produce electricity from an external supply of fuel and oxidant (typically oxygen or air, although chlorine and chlorine dioxide have also been used among others[1]) as opposed to the limited internal energy storage capacity of a battery. Additionally, while the electrodes within a battery react and change as a battery is charged or discharged, a fuel cell's electrodes are catalytic and relatively stable.
