What is Electric Battery ?

The earliest known artifacts that may have been batteries are the so-called "Baghdad Batteries," apparently used in the period between 250 B.C.E. and 640 C.E.

he term "battery" in this context was first used by Benjamin Franklin to describe a set of linked Leyden jars, the first capacitor and an early means of storing charge before the invention of true electrochemical batteries.

The modern development of batteries started with the Voltaic pile, invented by Italian physicist Alessandro Volta, who announced it in 1800.[1]. This battery consisted of a pile of zinc and copper discs separated by brine soaked

A British chemist named John Frederic Daniell searched for a way to eliminate gas buildup in the Voltaic pile. His solution was to use a second electrolyte to consume the hydrogen produced by the first.

In 1836, he invented the Daniell cell, which consisted of a copper pot filled with a copper sulfate solution, in which was immersed an unglazed earthenware container filled with sulfuric acid, in which was immersed a zinc electrode.

Up to this point, all batteries were permanently drained when their chemical reactions were spent.
In 1859, Gaston Planté invented the lead/acid cell, the first battery that could be recharged by passing a reverse current through it.

A lead/acid cell consists of a lead anode and a lead oxide cathode immersed in sulfuric acid. Both electrodes react with the acid to produce lead sulfate, but the reaction at the lead anode releases electrons whilst the reaction at the lead oxide consumes them, thus producing a current.

These chemical reactions can be reversed by passing a reverse current through the battery, thereby recharging it.

Planté's first model consisted of a sheet of lead and a sheet of lead oxide separated by rubber strips and rolled into a spiral.[2] His batteries were first used to power the lights in train carriages while stopped at a station

In 1881, Camille Faure invented an improved version that consisted of a lead grid lattice into which a lead oxide paste was pressed, forming a plate. Multiple plates could be stacked for greater performance

This design was easier to mass-produce. Toward the end of the nineteenth century, Carl Gassner replaced the liquid electrolyte with a paste, making a much more practical battery for mass consumption.

The manganese dioxide cathode had a little carbon mixed into it as well, which improved electrolyte conductivity and absorption.[3]
In 1887, Carl Gassner patented a variant of the Leclanché cell which came to be known as the dry cell because it did not have an free liquid electrolyte.

nstead, the ammonium chloride was mixed with Plaster of Paris to create a paste, with a bit of zinc chloride added in to extend the shelf life. The manganese dioxide cathode was dipped in this paste, and both were sealed in a zinc shell which also acted as the anode.

Near the turn of the twentieth century, early gasoline-powered cars were unreliable and the electric car was more popular. However, their popularity was limited by the very heavy lead-acid batteries on which they ran

Hoping to produce a more commercially viable electric car, Thomas Edison and his associates began searching for a more lightweight and durable rechargeable battery

In 1903 their research produced a battery that consisted of iron and nickel electrodes with potassium hydroxide as the electrolyte (hence the "alkaline" descriptor, though this battery is more commonly referred to as the nickel-iron battery).

However, consumers found this early version to be prone to leakage and short life; it did not outperform the lead-acid battery by much either. Edison went back to the drawing board and seven years later put out a more reliable and powerful model.

By this time, however, the inexpensive and reliable Model T Ford had made gasoline engine cars the standard. Nevertheless, Edison's battery achieved great success in other applications.

A battery is a device in which chemical energy is directly converted to electrical energy. It consists of one or more voltaic cells, each of which is composed of two half cells connected in series by the conductive electrolyte

In the figure to the right, the battery consists of one or more voltaic cells in series. The conventional symbol does not necessarily represent the true number of voltaic cells

Each cell has a positive terminal, shown by a long horizontal line, and a negative terminal, shown by the shorter horizontal line.

These do not touch each other but are immersed in a solid or liquid electrolyte.
The electrolyte is a conductor that connects the half-cells together. It also contains ions that can react with chemicals of the electrodes.

Chemical energy is converted into electrical energy by chemical reactions that transfer charge between the electrode and the electrolyte at their interface.

Such reactions are called faradaic, and are responsible for current flow through the cell. Ordinary, non-charge-transferring (non-faradaic) reactions also occur at the electrode-electrolyte interfaces. Non-faradaic reactions are one reason that voltaic cells (particularly the lead-acid cell of ordinary car batteries) "run down" when sitting unused.

Around 1800, Alessandro Volta studied the effect of different electrodes on the net electromotive force (emf) of many different types of voltaic cells. (Emf is equivalent to what was called the internal voltage source in the previous section.)