The battery was patented in 1800 by Alessandro Volta (now you know where “volt” comes from). Twenty years earlier, Volta witnessed his friend Luigi Galvani dissect a frog. Luigi hung the frog from a brass hook; and every time he stuck the blade of his scalpel into the frog’s leg, the frog started kicking. The baffled Luigi attributed it to “animal electricity”, but Volta later discovered that two different types of metal connected by a moist medium will generate electricity. The battery patented by Volta in 1800 consisted of various zinc and copper discs that were submerged in brine. You can thank Volta for every headlamp, portable radio and smartphone, and countless other inventions that rely on a battery.