Definition - What does Galvanic Cell mean?
A Galvanic Cell is an electrochemical device in which a spontaneous oxidation-reduction reaction is used to convert chemical energy into electrical energy. This chemical reaction produces an electric current through an outside circuit. Galvanic cell reactions supply energy and due to this reason, they are commonly used as batteries. In the real world, the word battery may also include a single galvanic cell, but a proper battery consists of multiple cells.
The cell consists of at least two half cells, a reduction cell and an oxidation cell. Chemical reactions in the two half cells provide the energy for the galvanic cell operations. Many galvanic cells are of commercial importance. These include dry cells, mercury cells, rechargeable Ni-Cd batteries, fuel cells and lead storage cells. A common galvanic cell is the Daniell cell.
Petropedia explains Galvanic Cell
Galvanic cells harness electrical energy available from the electron transfer in a redox reaction to create an electric current. Basically, a galvanic cell is used to convert the chemical energy stored in ions into electrical energy, in the form of current. For example, a battery is a package of one or more galvanic cells used for the production and storage of electric energy by chemical means. The key to gathering the electron flow is to separate the oxidation and reduction half-reactions and connect them by a wire so that the electrons can flow through that wire.
Galvanic cells are also important in corrosion protection. Any two metals can be used to make a galvanic cell. If two metals are in contact, one metal will be the anode and the other the cathode, and this may lead to galvanic corrosion. The metal which appears higher up on the list will, being the anode will corrode. The metal lower down on the list will be the cathode and thus will not corrode. This galvanic action will not take place under open-circuit conditions; there must be a connecting circuit.