Golf carts are a very poor example of any aspect of EV or HEV technology.
But much of the restart energy for a real start-stop drive system could come from a large capacitor, since with a warmed up fuel injected engine extended cranking would never be needed. One cylinder and one compression stroke and it should be running. A new battery technology may be quite worthwhile, but really, a capacitor should be able to deliver enough power for normal restarting. Of course the entire concept could easily be ruined by the wrong control algorithm, which I anticipate the first generation will be a miserable failure because the control algorithm will be totally wrong. The other requirements for maximum saving will be to allow driver control plus free-wheeling coasting. The downside is that it will require the vehicle to have non-powered steering, since the loss of power assist will render most drivers unable to steer the vehicle. But power steering for a small, light vehicle is really a waste of energy and an excess mechanical feature that only adds weight and complexity.
If one is to solve the energy demand problems in this country, no one solution will work. The Pacific NW has plenty of hydro electric potential, but is a rotten place for solar. The southwest is exactly the opposite. Tidal energy in Kansas is just plain silly.
A blended approach is necessary, multiple solutions. Might using two different types of batteries make a better solution for vehicles? This custom lithium chemistry for start-stop, and more conventional for regular operation?
The chemistry is beyond me but it sounds good. Why did the battery consortiom fork over millions of dollars for this technology. They could have gotten it much cheaper by going out and playing a round of golf in a golf cart. Golf carts have been stopping and starting for years.
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