Electrochemical Cells: Converting Chemical Energy into Electrical Energy and Vice Versa

Electrochemical cells are devices that convert chemical energy into electrical energy or vice versa through the use of redox reactions. They consist of two electrodes, an anode and a cathode, which are connected by a conductive electrolyte solution.

During the operation of an electrochemical cell, electrons flow from the anode to the cathode through an external circuit, while ions flow from the anode to the cathode through the electrolyte solution. This movement of electrons and ions generates an electrical potential difference between the electrodes, which can be measured as the cell voltage or electromotive force (EMF).

There are two main types of electrochemical cells: galvanic (or voltaic) cells and electrolytic cells. Galvanic cells convert chemical energy into electrical energy, while electrolytic cells use electrical energy to drive a non-spontaneous chemical reaction.

In a galvanic cell, the anode is the site of oxidation, where the metal or other substance loses electrons and becomes oxidized, while the cathode is the site of reduction, where the metal or other substance gains electrons and becomes reduced. This results in a spontaneous redox reaction and the generation of electrical energy.

In an electrolytic cell, an external source of electrical energy is used to drive a non-spontaneous redox reaction. The anode is the site of oxidation, where electrons are removed from the metal or other substance, while the cathode is the site of reduction, where electrons are gained by the metal or other substance.

Electrochemical cells have practical applications in various industries, including batteries, fuel cells, electroplating, and corrosion protection. They are also used in medical devices, such as pacemakers and neurostimulators.