Italian scientist Alessandro Volta is credited as the inventor of the electrical battery, but a frog played a role. Volta’s invention, the voltaic pile, was made up of pairs of copper and zinc discs on top of each other. A layer of cloth or cardboard soaked in brine separated the discs, and acted as the electrolyte. This produced a stable and continuous current, and lost little charge over time when not in use – although the voltage wasn’t strong enough to produce sparks…