Electric vehicles use energy storage systems like batteries to power electric motors instead of internal combustion engines. There are three main types of electric vehicles: fully battery electric vehicles which are powered solely by batteries; hybrid electric vehicles which have both a battery and combustion engine; and other electric vehicles like trains and ships. Batteries, supercapacitors, and fuel cells are common energy storage devices used in electric vehicles. Hybrid storage systems combine different device types. A battery management system monitors and controls the energy storage system to keep it safe and maximize its lifespan.