Galvanic Cells: Definitions, Examples, How They are Created,  Principles, Parts, Working and Uses

Galvanic Cells Overview

Volta was the inventor of the voltaic pile, the first electrical battery. In common usage, the word "battery" has come to include a single galvanic cell, but a battery properly consists of multiple cells. A galvanic cell, often known as a voltaic cell after the scientists Luigi Galvani and Alessandro Volta, is an electrochemical cell in which an electric current is created by spontaneous Oxidation-Reduction events.

What are Galvanic Cells?

A galvanic cell, or voltaic cell, is an electrochemical cell that transforms the chemical energy of spontaneous redox reactions into electrical energy. It is an electrochemical cell that generates electrical energy through chemical processes.

Examples of Galvanic Cells

More than a century ago, electrochemical or galvanic cells were created as a technique for researching the thermodynamic features of fused salts. A galvanic cell, such as Daniel's cell, turns chemical energy into electrical energy. In Daniel's cell, copper ions are reduced at the cathode while zinc ions are oxidized at the anode. Daniel's cell reactions at the cathode and anode are as follows-

At cathode: Cu2+ + 2e- → Cu

At anode: Zn → Zn2+ + 2e-

How Galvanic Cells are created?

Electrons are transferred from one species to another in oxidation-reduction processes. If the reaction occurs spontaneously, energy is liberated. As a result, the liberated energy is put to good use. To deal with this energy, the reaction must be separated into two half-reactions, which are as follows-

1. Oxidation
2. Reduction

The reactions are put into two distinct containers, and wires are used to move the electrons from one end to the other. This results in the formation of galvanic cells or voltaic cells.

Principle of Galvanic Cells

The Gibbs energy of the spontaneous redox reaction in the voltaic cell is primarily responsible for the electric work done by a galvanic cell. It is typically made up of two half-cells and a salt bridge. Each half-cell also has a metallic electrode immersed in an electrolyte. These two half-cells are externally linked to a voltmeter and a switch via metallic cables. When both electrodes are immersed in the same electrolyte, a salt bridge is not always necessary.

Parts of Galvanic Cells

The following are some parts of the Galvanic cells-

1. Anode: This electrode undergoes oxidation.
2. Cathode: This electrode undergoes reduction.
3. External Circuit: Allows electrons to pass between electrodes.
4. Half Cells: compartments for reduction and oxidation processes.
5. Load: A component of the circuit that uses electron flow to fulfill its job.
6. Salt bridge:  A salt bridge contains electrolytes that are needed to complete the circuit in a galvanic cell.

Working of Galvanic Cells

The following is the working of Galvanic Cells-

1. A galvanic cell makes use of the ability to split the flow of electrons during the oxidation and reduction processes by creating a half-reaction and connecting each with a wire so that a conduit for the flow of electrons through such a wire may be constructed. 
2. This movement of electrons is referred to as a current.
3. A current of this type may be produced to flow via a wire in order to complete a circuit and acquire its output in any device, such as a television or a watch.
4. Volta was the inventor of the voltaic pile, the first electrical battery. In common usage, the word "battery" has come to include a single galvanic cell, but a battery properly consists of multiple cells.
5. A galvanic cell may be constructed from any two metals. 
6. If these two metals come into contact with each other, they can create the anode and cathode. This combination allows for galvanic corrosion of the more anodic metal. 
7. To allow this corrosion to occur, a connecting circuit will be necessary.

Uses of Galvanic Cells

The following are some of the uses of Galvanic Cells-

Galvanic cells are employed in the commercial manufacturing of batteries because they transfer chemical energy to electrical energy.

This may be used to power remote controls, clocks, torches, and even electric vehicles. Galvanic cells are classified into two types-

1. Primary (disposable) Batteries: Primary batteries are single-use, non-rechargeable batteries with irreversible electrode reactions.
2. Secondary (rechargeable) Batteries: Secondary batteries are rechargeable and include an insoluble element that adheres to the electrodes. They function as ordinary galvanic cells when in use and as electrolytic cells when charging.