imkazaam said:
The REX has two power sources that can both be used to power the car, and that is, by definition, a hybrid powered vehicle. The REX is a serial hybrid, where the one power source feeds into the second, and the second provides the final propulsion, and the first is optional.
The Toyota/Ford and a few others are parallel/serial hybrids where the propulsion can be entirely electric, or gas plus electric, but not gas alone (although the batteries are not strictly needed once the engine is running, the electric motors propulsion is mandatory and are used to mix the electric and gas power).
The original Honda Insight was a purely parallel hybrid system where the gas engine and the electric motor were always turning together, and either one alone could be powered, or both could contribute, however, when the engine was off, it did add drag to the system, unlike the serial/parallel system that could effective bypass the engine with virtually no drag.
It is wrong to say the REX is not a hybrid propulsion system. It would be just as wrong to say any plug-in hybrid such as the plug-in Prius is not a hybrid, just because they are capable of extended pure electric propulsion, while the gas engine sits non-rotating. The REX is simply less (WAY LESS!) dependent on the second energy source than most other hybrids.
Less clarity of hybrid/non-hybrid can be found with a fuel-cell-electric vehicle, especially if plug-in capable.
