Electric battery common fuels such as gasoline. In automobiles, this is somewhat offset by the higher efficiency of electric motors in converting chemical energy to mechanical work, compared to combustion engines. The usage of "battery" to describe a group of electrical devices dates to Benjamin Franklin, who in 1748 described multiple Leyden jars by analogy to a battery of cannon (Benjamin Franklin borrowed the term "battery" from the military, which refers to weapons functioning together). Italian physicist Alessandro Volta built and described the first electrochemical battery, the voltaic pile, in 1800. This was a stack of copper and zinc plates, separated by
Battery electric vehicle from 56,000 units in 1998 to over 21 million in 2008, and reaching an estimated 120 million e-bikes on the road in early 2010. China is the world's leading manufacturer of e-bikes, with 22.2 million units produced in 2009. Some of the biggest manufacturers of E-bikes in the world are BYD, Geoby. An increasing variety of personal transporters are being manufactured, including the one-wheeled self-balancing unicycles, self-balancing scooters, electric kick scooters, and electric skateboards. Several battery electric ships operate throughout the world, some for business. Electric ferries are being operated and constructed. The motor controller receives a signal from potentiometers