What's the Hybrid Electric Vehicle

A hybrid electric vehicle is a vehicle which combines a conventional propulsion system with an on-board rechargeable energy storage system (RESS) to achieve better fuel economy than a conventional vehicle without being hampered by range from a charging unit like a battery electric vehicle (BEV), which uses batteries charged by an external source. The different propulsion power systems may have common subsystems or components.

Regular HEVs most commonly use an internal combustion engine (ICE) in tandem with electric motors to power their propulsion system. Modern mass-produced HEVs prolong the charge on their batteries by capturing kinetic energy via regenerative braking, and some HEVs can use the combustion engine to generate electricity by spinning an electrical generator (often a motor-generator) to either recharge the battery or directly feed power to an electric motor that drives the vehicle. Many HEVs reduce idle emissions by shutting down the ICE at idle and restarting it when needed. An HEV's engine is smaller and may be run at various speeds, providing more efficiency.