[edzo4]

i believe the volt is also a hybrid with extra batteries, you can charge it drive 40 miles using no gas then the hybrid kicks in to generate more power

[taildragger]

The Volt is a "Series Hybrid"

It is esentially an all electric drivetrain. The engine runs at a constant RPM when it is on to send the juice to the battery. If you charge it and run it less than 40 miles, the engine doesn't kick in. The braking has a regenerative mode, so you capture the loss energy of braking.

Same concept as a locomotive but with a battery added.