Indeed they may simply help to extend the lifespan of the internal combustion engine longer than it would otherwise survive.
Rechargeable electric cells offer a clue, but remain ludicrously inefficient in power to weight ratios when compared to the internal combustion engine.
lighter-than-air vehicle with internal combustion engine and air propeller was the obvious route.
For anyone who thinks you need an internal combustion engine to get serious driving performance, the Tesla Roadster is happy to prove you wrong.
The parallel hybrid has the electric motor, the batteries and the combustion engine all connected to the transmission.