The Baghdad battery (also referred to as the Parthian battery) is a set of three curious artifacts which was invented during the Parthian or Sassanid periods. The items were discovered in the village of Khuyut Rabbou’s in modern day Iraq. The Baghdad Batteries are actually terracotta pots which are approx. 115 mm to 140 mm tall. The most amazing thing about this discovery is that if it is in fact, a battery that would mean that batteries were invented roughly 2,000 years before modern history suggests electricity was discovered by humans. They found that by adding copper sulfate, acetic acid, or citric acid all of which were well known two thousand years ago the battery produced between one and a half and three volts of electricity. It is believed that the batteries were used in ancient times for electroplating gold onto silver objects.
People still do have a lucid idea about its discovery and still its sources are conflicting. It is said to have been discovered either among other artifacts at the National Museum of Iraq, by archaeologist Wilhelm Konig in 1938 or it was discovered in the Khujut Rabu ruins near Baghdad, in 1936. There are other several artifacts that resemble this battery found throughout ancient Mesopotamia, mostly used to store papyrus. Konig found that the vase was made up of yellow clay which was estimated to be roughly 2,000 years old. Inside of the pot was a copper cylinder that was soldered using 60-40 lead-tin alloy. The bottom was capped with copper and sealed with asphalt. An iron rod was placed in the cylinder and held in place with more asphalt. It is often assumed that an acidic agent, such as vinegar or wine was poured into the device because the iron rods show some signs of having been corroded by such a liquid.
It is believed that if they were indeed intended to be used as batteries, it is thought that they were most likely used or electroplating purpose as it produced very little voltage. According to the given descriptions of these batteries, these were sealed at the top with metal pieces so it would have been nearly impossible to connect them to anything even if they did produce electricity unless the design is altered. No wires or any conductors have been found or associated with this battery. It is possible to construct a Baghdad battery today also with minor modification.