Yes, absolutely. There are hundreds of LiFePO4 sportbike, ATV, and race car batteries on the market already (for example, http://www.batterystuff.com/powersport

Yes, absolutely. There are hundreds of LiFePO4 sportbike, ATV, and race car batteries on the market already (for example, http://www.batterystuff.com/powersports-batteries/LFX14L2-BS12.html http://www.batterystuff.com/powersports-batteries/LFX14L2-BS... ). I've also used one to run my Elise (2ZZ 1.8L 4-cylinder) for a few years now without issue. The three major issues I've heard about are are longevity, price, and reserve capacity. Cold weather is a bit of an issue, but strangely it's actually made better by more load as the battery's internal resistance eventually heats it up to the point that it works fine. I really don't get this product yet. Unless the supercapacitor provides an incredible enhancement in longevity (maybe it does, but my understanding and experience is that temperature and poor manufacturing are the main enemies to these batteries, not instantaneous load), I'm not sold on buying one instead of one of the inexpensive existing alternatives.