Alessandro Volta (1745-1827) was the inventor
of the electric battery
It all started when in the 1780's, Luigi Galvani (1737-1798), a professor at the University of Bologna was carrying out a set of experiments, applying electrical current to a frog's leg muscle and studying its contraction. While he was doing this, he made a startling discovery -- when a brass hook was stuck in the frog's spinal cord and another part of the frog touched with an iron rod, all that was needed to make the leg muscle contract was to touch the brass hook and iron rod together. After some more experimentation, Galvani found other pairs of metals that exhibited this unusual phenomenon. Galvani, understandably believed the source of energy came from the frog... after all, how could two peices of metal create energy? He published his conclusions in 1791, calling the energy 'animal electricity'.
Volta, of the University of Pavia was at first skeptical of Galvani, but repeating Galvani's experiments soon convinced him. However, Volta doubted Galvani's 'life force' explanation. He published his own conclusion that the force came from the contact of the two metals and effectively split the scientific community between himself and Galvani.
Volta realised that the frog's muscle was behaving like an electroscope, and could be used to measure electrical tension. Thus, to disprove the 'life force' hypothesis, he only had to replace the frog's leg with an electroscope. However, the most accurate electroscopes Volta had access to measured 40 V per degree. However, he was able to estimate the potential differences produced by dissimilar metals very accurately. Volta also created the electrochemical series, a list of metals in order of charge produced, which is still in use by modern scientists.
However, Volta had still to create his greatest invention. He created the voltaic cell. He stacked up a large group (a 'battery') of silver and zinc plates, separated by peices of salt-soaked cloths. This 'electric pile' produced a much greater potential difference. Indeed, he was able to actually produce sparks by bringing together pieces of metal connected to the ends of the pile. Volta created the first battery, a 'wet cell', as opposed to modern dry cells that don't need to be soaked in water. It is safe to say that Volta's discovery was one of the main factors in forstering the electrical revolution.