In 1936, four 5-inch-tall ceramic jars were found about 20 miles southeast of modern-day Baghdad, and these mysterious ... is filled with a weak acid, the “battery” makes about 1 volt of ...

The Baghdad Battery is believed to be about 2000 years old (from the Parthian period, roughly 250 BCE to CE 250). The jar was found in Khujut Rabu just outside Baghdad and is composed of a clay jar ...