A battery is a collection of one or more electrochemical cells that can be charged electrically to provide a static potential for power or released electrical charge when needed. When an external load connects to a battery, electrons travel from the negative to the positive terminal, creating an electrical current.

This current may power a motor, a light bulb, a clock, a computer, a cell phone, and other electronic devices or equipment. Batteries are available in numerous sizes, which range from the miniature cells used in wrist watches to large batteries that can support grids.

Some of the commonly used batteries are Lead Acid Batteries, Lithium Ion Batteries, Nickel Cadmium Batteries, Nickel Metal Hydride Batteries, Zinc Air Batteries and Nickel Iron Batteries.