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STORAGE BATTERY TECHNOLOGIES 57

Figure 3.7 The Baghdad
battery elements.

an ancient electric battery. It is stipulated that the Sumerians made use of the battery
for electroplating inexpensive metals such as copper with silver or gold.
Subsequent to the discovery of this first battery, several other batteries were unearthed
in Iraq, all of which dated from the Parthian occupation between 248 BCE and 226 CE.
In the 1970s, German Egyptologist Arne Eggebrecht built a replica of the Baghdad
battery and filled it with grape juice, which he deduced ancient Sumerians might
have used as an electrolyte. The replica generated 0.87 V of electric potential.
Current generated from the battery was then used to electroplate a silver statuette
with gold.
However, the invention of batteries is associated with the Italian scientist Luigi
Galvani, an anatomist who, in 1791, published works on animal electricity. In his
experiments, Galvani noticed that the leg of a dead frog began to twitch when it came
in contact with two different metals. From this phenomenon he concluded that there
is a connection between electricity and muscle activity. Alessandro Conte Volta, an
Italian physicist, in 1800, reported the invention of his electric battery or “pile.” The
battery was made by piling up layers of silver, paper or cloth soaked in salt, and zinc
(see Figure 3.8). Many triple layers were assembled into a tall pile, without paper or
cloth between the zinc and silver, until the desired voltage was reached. Even today
the French word for battery is pile, pronounced “peel” in English. Volta also developed
the concept of the electrochemical series, which ranks the potential produced when
various metals come in contact with an electrolyte.