This means that it is equipped with the "Smart Alternator". It charges the battery depending on the driving condition or if enough capacity is available in the batteries it supports the engine with horsepower e. g. at full load in mountain rides. In this case also the leisure batteries are discharged and there may be a loss of capacity in the batteries.
This was copied from further up the thread and describes what i was told and was exactly what I experienced with the smell of rubber. Some vehicles use regenerative braking to supply electrical power but not as far as I know Iveco. I just don't see a serpentine belt as a sensible means to add propulsion power to a vehicle.