Someone should try to hook up some ultra capacitors to the Prius. There was a thread in Priusonline.com that showed an article that had a BMW X5 hybrid with ultracapacitors turning out 1,350 lbs of torque and a 40% increase in speed. If the Prius had a 40% increase in speed... thats 5.8 seconds from 0-60. IF that were the case when ultra capacitors were added.
In this application, the only differences between a supercap/ultracap and the existing battery is the rate of charge and rate of discharge in operation, and the rate of leakage when not in operation. The limiting factor in the Prius is still the amount of current through MG1 and MG2 - controlled by the system. Even if you had ultracaps offering 10x the existing supply, and some way to "tell" the management system it's available, you would have no way to use it unless you redesigned the entire system. In the Toyota "race car" at http://tinyurl.com/2ojpr, the designers were willing to make the "minor" change of a new engine, but were not willing to rework the electrical management system.
Not just reconfigure the CPU, you'd have to replace the MGs with bigger ones, which might require a heftier PSD. The real advantages you'd get from adding electric storage capacity (whether more batteries, or ultra-capacitors) would be a big increase in electric range, and a small improvement in efficiency due to the increased load-balancing capacity.
Actually because MG2 comes after the PSD - the only thing that may need strengthening would be the final drive chain, counter cears or differential. Or if you were really adding torque, perhaps the drive axles as well But, given that MG2 would get biiger, I'd imagine you'd want to feed it appropriately, so MG1 would need to be beefier as well, which would require a larger PSD. Here's my thought - I wonder if one could mate the Prius engine (or a variant) to the Highlander/RX400h PSD/MG1/MG2/driveline?
MG1 is the generator and starter. MG2 is the traction motor and regenerative braking generator PSD is the power split device. Feel free to consult the Knowledge Base here on Prius chat for a full comprehensive list of other "acronyms" related to Prius. It will make your Prius Chat experience much more pleasant. The URL for that is here: http://priuschat.com/forums/kb.php?mode=article&k=3 Ironically, it doesn't include the 3 above definitions - we need to fix that!
