In fuel cell science, the difference between basic electrochemical processes and fuel cell systems engineering is bridged by fuel cell physical modeling. During the creation of practical units in the last three decades, there is a need for a better understanding of the basic processes which determine the activity of fuel cells.
An electrochemical cell is a single arrangement of two electrodes and an electrolyte for producing an electric current due to chemical action within the cell, or for producing chemical action due to passage of electricity. A galvanic cell, also known as voltaic cell is a device in which electrical current is generated by a spontaneous redox reaction.
How Does Hydrogen Fuel Cell Work?
The fuel cell is an electrochemical device, similar in concept to a battery that exploits a chemical reaction in order to generate electricity. The normal source of hydrogen for Hydrogen Fuel Cell today is the reformation of natural gas. The reforming process produces a gas composed primarily of hydrogen and carbon dioxide with small amounts of other impurities such as carbon dioxide, carbon monoxide, nitrogen and unreacted methane.
The typical basic reaction for fuel cells is the formation of water by means of two different electrochemical reactions between hydrogen and oxygen. According to the stoichiometry of the reactions, each hydrogen molecule produces two electrons. The electrical work associated with moving of charge is denoted as
W (electrical) = q E
Where q = total charge, E = potential difference.
Uses of Galvanic Cells
A ‘galvanic cell’ produces electrical energy, whereas an ‘electrolytic cell’ uses or absorbs electrical energy. A galvanic cell uses a spontaneous chemical reaction to generate a potential difference and deliver an electric current to an external device. It uses an external potential difference to drive a chemical reaction in the cell that is by itself non-spontaneous.
Galvanic cells use redox reactions to generate electrical current. Galvanic cells find wide usage in the form of batteries. However, things have turned out differently and the fuel cell of today is a successful portable device exclusively used in space research.