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In 1802, Dr. William Cruickshank designed the first electric
battery capable of mass production. Cruickshank had arranged
square sheets of copper, which he soldered at their ends,
together with sheets of zinc of equal size. These sheets were
placed into a long rectangular wooden box that was sealed
with cement. Grooves in the box held the metal plates in position.
The box was then filled with an electrolyte of brine, or watered
down acid.
Figure 4: Cruickshank and the first
flooded battery.
William Cruickshank, an English
chemist, built a battery of electric cells by joining zinc
and copper plates in a wooden box filled with electrolyte.
This flooded design had the advantage of not drying out with
use and provided more energy than Volta’s disc arrangement.
© Cadex Electronics Inc.
The third method of generating electricity was discovered
relatively late — electricity through magnetism. In 1820,
André-Marie Ampčre (1775-1836) had noticed that wires carrying
an electric current were at times attracted to one another,
while at other times they were repelled.
In 1831, Michael Faraday (1791-1867) demonstrated how a copper
disc was able to provide a constant flow of electricity when
revolved in a strong magnetic field. Faraday, assisting Davy
and his research team, succeeded in generating an endless
electrical force as long as the movement between a coil and
magnet continued. The electric generator was invented. This
process was then reversed and the electric motor was discovered.
Shortly thereafter, transformers were developed that could
convert electricity to a desired voltage. In 1833, Faraday
established the foundation of electrochemistry with Faraday's
Law, which describes the amount of reduction that occurs in
an electrolytic cell.
In 1836, John F. Daniell, an English chemist, continued with
the research of the electro-chemical battery and developed
an improved cell that produced a steadier current than Volta's
device. Until then, all batteries had been composed of primary
cells, meaning that they could not be recharged. In 1859,
the French physician Gaston Platé invented the first rechargeable
battery. This secondary battery was based on lead acid chemistry,
a system that is still used today.
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