Battery (electricity)
Various batteries (clockwise from bottom
left): two 9-volt PP3, two AA, one D, one
handheld ham radio battery, one cordless
phone battery, one camcorder battery, one C,
two AAA.
In electronics, a battery or voltaic cell is a
combination of one or more electrochemical
Galvanic cells which store chemical energy.
These cells create a voltage difference
between the terminals of the battery. When
an external electrical circuit is connected to
the battery, then the battery drives an elec-
tric current through the circuit and electrical
work is done. Since the invention of the first
Voltaic pile in 1800 by Alessandro Volta, the
battery has become a common power source
for many household and industrial applica-
tions, and is now a multi-billion dollar
industry.
The name "battery" was coined by Ben-
jamin Franklin for an arrangement of mul-
tiple Leyden jars (an early type of capacitor)
after a battery of cannon.[1] Common usage
includes a single electrical cell in the defini-
tion.[2][3]
History
An early form of electrochemical battery
called the Baghdad Battery may have been
used in antiquity.[4] However, the modern de-
velopment of batteries started with the Volta-
ic pile, invented by the Italian physicist Aless-
andro Volta in 1800.[5]
In 1780
the
Italian anatomist
and
physiologist
Luigi Galvani
noticed
that
dissected frog’s legs would twitch when
struck by a spark from a Leyden jar, an ex-
ternal source of electricity.[6] In 1786 he no-
ticed that twitching would occur during light-
ning storms.[7] After many years Galvani
learned how to produce twitching without us-
ing any external source of electricity. In 1791
he published a report on "animal electri-
city."[8] He created an electric circuit consist-
ing of two different metals, with one touching
a frog’s leg and the other touching both the
leg and the first metal, thus closing the cir-
cuit. In modern terms, the frog’s leg served
as both the electrolyte and the sensor, and
the metals served as electrodes. He noticed
that even though the fr