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Old 06-27-2010, 08:08 AM   #19 (permalink)
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Quote:
Originally Posted by jamesqf View Post
See here, just a dozen or so threads down in this section: http://ecomodder.com/forum/showthrea...ace-13310.html

The big advantage of flywheel storage, especially in a racing application, is that it's not really rate-limited. That is, with a battery you can only put energy in or take it out at a certain limited rate (which depends on battery chemistry etc), while a flywheel will basically take anything that doesn't melt the wires.
One of the essential components of a purely mechanical flywheel energy recovery system, is a Infinitely Variable Transmission to store and apply the energy.

IVTs are very new technology. CVTs date back to the mid 1950s in automotive applications. I believe it was the Van Doorne Belt system that was first used in a DAF car in Europe (Holland or Belgium).

The problem was with the belt itself, and it took several decades for the belt technology to improve.

Nissan has recently extended the warranty on their CVTs to 10 years and 120k miles to address customer concerns about reliability.

10 years ago the EPA's hydraulic hybrid research efforts concluded that the "missing link" was a highly efficient IVT hydraulic transmission was the place where development should be concentrated. Even without that development they built a 3800 pound test mule vehicle that average 80 MPG.

NASA flywheel batteries for energy storage in space flight is also an interesting subject. 6 months at something like 95% of the original energy storage level.

Vacuum chamber, magnetic bearings, mega bucks, and not really practical for automotive applications.

I hope KERs is not dead yet. When you think that the first couple of years of development was actually competitive, compare that to the amount of time we have been chasing a practical BEV battery.

It's not that I am an opponent of chemical batteries. Think of it more as being an advocate of higher efficiency regardless of the means by which it is achieved as long as the trade offs are not safety and environmental risks.

regards
Mech
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