FUEL CELL : INTRODUCTION AND WORKING EXPLAINED !!

Fuel Cell Technology which is expected to do wonders once accepted globally. A fuel cell is an electrochemical cell converting energy from a fuel into electrical energy and reactions taking place between the fuel supply and an oxidizing agent result in the generated electricity.

Making it more convenient to understand we can say that a fuel cell converts the chemicals hydrogen and oxygen into water, and in the process it produces electricity. Another very common example of an electrochemical device is a battery which is used almost everywhere.

But of all the characteristics the most important one of a Hydrogen Fuel Cell is that it is capable of staying alive for a much longer period as compared to the conventional battery which becomes dead after a couple of hours or days or at most a few months.

Hydrogen Fuel Cell Working :

Fuel cells are of several types but the most promising and efficient is the one we are going to explain here. Called as Polymer Exchange Membrane Fuel Cell (PEMFC), this type is most suitable for powering car, buses and even houses. The working of the same uses one of the simplest reactions of any fuel cell and constitutes of an Anode, Cathode, and Electrolyte and a Catalyst.

•          The negative anode plays the role of conducting the electrons that are freed from the hydrogen molecules and also disperses Hydrogen gas equally over the catalyst.
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•          The channels located on the Cathode as well perform the task of distributing oxygen over the catalyst and also conducts the electrons to the catalyst from external circuit.
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•          A proton exchange membrane acts as the electrolyte which only allows positively charged ions to pass through it and hence blocks electrons.
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•          The catalyst is an important constituent which enhances or speeds up the reaction between hydrogen and oxygen.

Working: Now what happens is that Hydrogen gas enters the fuel cell from the anode part where it is split into two H+ ions after being forced through the catalyst. The electrons thus flow into the external circuit and perform the required work like turning a motor etc. and return to the cathode.

Meanwhile Oxygen gas is forced through the catalyst after entering from the cathode side where it is split into two negative oxygen atoms.

    At last the negative oxygen ions attract the lighter hydrogen ions through the membrane eventually combining and resulting in Water(H2O).