Batteries are devices that have been helping mankind for a long time. But nobody knows exactly when they were invented.
An account of the earliest battery came in 1938 from Baghdad. The story goes that while constructing a railway line in the city, workers uncovered a pre-historic battery. Experts said that the battery belonged to the Parthian Empire, and was at least 2000 years old!
Luigi Galvani, in 1786, was conducting an experiment when he accidentally touched a dead frog’s legs with two different metals. Suddenly the muscles of its legs contracted. He thought it was because of ‘animal electricity’. But his friend and fellow scientist Alessandro Volta didn’t agree. He guessed that the same effect would be produced if cardboard was soaked in salt water, instead of a frog’s leg. So, he stacked copper and zinc discs, separated by a cloth, and soaked them in salt water. He connected wires to either end of the stack.
To his surprise, it produced stable current. Thus in 1800, Volta invented the ‘voltaic pile’, the first true battery that produced continuous and stable current. This is believed to have laid the foundation for the modern battery.
