Fundamentals of a Fuel Cell

A fuel cell is an electrochemical conversion device. It produces electricity from fuel and an oxidant, which react in the presence of an electrolyte. The reactants flow into the cell, and the reaction products flow out of it, while the electrolyte remains within it. Fuel cells are different from electrochemical cell batteries in that they consume reactant, which must be replenished, whereas batteries store electrical energy chemically in a closed system. The chemical energy of the fuel is released in the form of an electrical energy instead of heat when the fuel is oxidized in an ideal electrochemical cell. Energy conversion by a fuel cell depends largely 

Typical reactants used in a fuel cell are hydrogen on the anode side and oxygen on the cathode side (a hydrogen cell). Usually, reactants flow in and reaction products flow out. Vrrtually continuous long-term operation is feasible as long as these flows are maintained. 

Like electrochemical cells, all fuel cells consist of a pair of electrodes, i.e., cathode and anode, and an electrolyte, pltts an external circrrit for electrical crrrrent and 

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