Battery Basics

Chemistry is the driving force behind any battery. A battery, by definition, is a package of one or more galvanic cells used for the production and storage of electrical energy by chemical means. The galvanic cell consists of at least two half-cells, a reduction cell and oxidation cell. The chemical reactions in the half-cells provide the energy for the galvanic cell operation. Each half-cell consists of an electrode and an electrolyte solution. Typically, the solution contains ions created from the electrode in an oxidation-reduction reaction. To explain the electrochemistry in the galvanic cell, the diagram below can be used:

In this example, when zinc is placed into a salt solution (in the half-cell), the zinc tends to lose electrons. This loss of electrons is called oxidation and takes place at the anode. Conversely, for the half-cell containing copper in the salt solution, the copper tends to gain electrons. This is referred to as reduction and happens at the cathode. When the two cells are connected via the salt bridge or electric conductor to form a closed circuit, the arrangement becomes a galvanic cell or battery. The voltage generated for this battery is 1.1Volts.