Fast-charging batteries are all nice and good, but the lifespan matters, too -- why should you have to replace power packs (or entire devices) every couple of years ? You may not have to give up performance or longevity if researchers at Nanyang Technology University have their way. They've developed new lithium ion batteries that can reach a 70 percent charge in two minutes, but should also last for over 20 years -- several times longer than the cells in your current laptop or smartphone. The trick is using titanium dioxide nanotubes for the anode (the negative pole) instead of graphite; they both speed up the battery's chemical reactions while offering 10,000 charging cycles instead of the usual 500.