Galvanic cells consist of two half-cells, each containing an electrode (anode and cathode) and an electrolyte solution. When two different metals/electrodes are connected through an external wire and placed in separate containers of the electrolyte solutions, a chemical reaction occurs, and electrons are transferred from one electrode to the other. The movement of electrons creates an electrical current, and the cell generates an electrical potential or voltage.
The chemical reactions taking place in the half-cells involve oxidation (loss of electrons) at the anode and reduction (gain of electrons) at the cathode. The overall chemical reaction leads to the release of electrical energy, which can be harnessed for various applications like powering devices or charging batteries.
Examples of galvanic cells include batteries like the lead-acid battery used in cars or the lithium-ion batteries in electronic devices. In these batteries, chemical reactions between the electrodes, such as lead and lead oxide or lithium and metal oxides, produce an electrical current and generate the necessary voltage to operate the devices.
