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
Electric vehicle battery battery). In 2012, McKinsey Quarterly linked battery prices to gasoline prices on a basis of 5-year total cost of ownership for a car, estimating that $3.50/gallon equate to $250/kWh. In 2017 McKinsey estimated that electric cars are competitive at a battery pack cost of $100/kWh (around 2030), and expects pack costs to be $190/kWh by 2020. In October 2015, car maker GM revealed at their annual Global Business Conference that they expected a price of $145 per kilowatt hour for Li-ion cells entering 2016. Driving range parity means that the electric vehicle has the same range than an average all-combustion