Flywheels As Bridges
On the other hand, batteries are slow to charge and discharge but are good for sustained cruising. Using supercaps and batteries together could provide for a wide range of power needs. Except thus far it doesn’t seem there’s any way to charge batteries quickly and maintain their service lifespans.
Possibly then a mechanical flywheel could be used as a bridge between the two in the sense that an on-board supercapacitor could be quickly charged and enable a vehicle to get back on the road. The supercap quickly charges the flywheel, and then the flywheel slowly charges the batteries.
At this point flywheel capability in a vehicle application is relatively unknown but it’s a potentially useful technology path. And with Formula 1 featuring KERS (Kinetic Energy Recovery Systems) next year, this is a great opportunity for technology transfer from racing to the street.