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Bottled energy

The LEYDEN jar is, without doubt, the first known apparatus for storing electricity.

Generally it consists of a glass jar, within which is enclosed a sheet of tin or silver foil linked to an external rod.

A second sheet of foil is attached to the outside of the jar.

There are also models which have a double brass flask, separated by either air or glass to serve as an insulator. An example of such a model is shown in the image opposite.

This apparatus, the original capacitor, was unable to provide current during a sustained period and was discharged almost instantaneously.

Removable leyden jar (circa 1900)

From VOLTA's time, many researchers became motivated to find a source of electricity which was readily available, easily transportable and capable of delivering a constant current over long periods of time.

The earliest generators capable of storing a substantial quantity of electrical energy were based on the electro-chemical exchanges between metals.

They fell into two categories:

- Batteries or (Primary)

- Rechargeable Batteries (Secondary)

Other types of battery exist, of course, such as thermo-electric or fuel cells which are recent concepts and out of scope of this site.

© 2000-2007 Pierre Dessapt