I've avoided commenting on specific battery technology because there are a number of promising technologies in development but nothing that appeared ready for prime time, until now. I've been watching DBM and their Kolibri battery for a few months and they seem to have something that may qualify as a breakthrough. They have been working on a variant of lithium polymer batteries and seem to have come up with viable solutions to some of the problems inherent in Li po cells. Li po cells have the ability to put out a lot of power from a small package, but they have typically had limited cycle life and a tendency to explode if not handled properly. DBM claims to have solved both problems as well as increased their energy density and achieved unheard of economics in cell construction. They did a well publicized test in Germany with the backing of the German government and Lekker Energie
If the cells are around 250 wh/kg or better and can be economically manufactured they would indeed be a game changer compared to what is currently in use.
Here is a video of independent abuse testing where the cells were vibrated, smashed, and heated with no catastrophic effects. Click on the "CC" icon on the right to get subtitles.
Another video www.ftd.de/unternehmen/:wirtschaft-auf-dem-weg-zum-elektroauto/60038567.html
Longer article http://gm-volt.com/2011/04/12/cost-effective-ev-battery-reportedly-passes-tests-recharges-in-minutes/
There is still not enough concrete information to know if this is a realistic breakthrough but as time goes on and evidence piles up it seems as if this may be an actual product with real world potential. It's worth keeping an eye on.