They're putting Li-Ion batteries in cars! Are they nuts?!
At first I thought it was just the random person ... Now it seems there are lots of folks trying to soup up Hybrid electric cars with Lithium-Ion batteries! Are they nuts?! Li-Ion can be very very unstable and dangerous. Deform or puncture one and you'll have a very quick flash of fire and explosion.
You probably aren't going to throw around and mutilate your laptop so it's okay in there, but putting it in a car is just asking for trouble. Car's mean potential for accidents, which means potential for battery getting deformed, which means a big kabooom. And you can only wonder about adding gasoline to that situation. There is a reason no sane car manufacturer puts Li-Ion batteries in cars. Hybrid cars use NiMH batteries for a reason. So is the case with the more than a century old Lead Acid battery still used in normal cars.
Putting your own life in danger is one thing but driving around with what amounts to essentially a bomb and putting others' life in danger is totally irresponsible and should be against the law. Please do us all a favour and put a big sign saying "Li-Ion powered car" so I can stay far away from such things. Since most of these are being done on existing hybrid cars, I'm going to be wary of driving around one from now on. Especially Toyota Priuses.
Edit: There are safe versions of Li-Ion batteries in development but it doesn't look like its being used in some of these souped up hybrids being reported.