One nagging issue with electric vehicles is range. While today's lithium-ion (Li-ion) batteries are much better than yesterday's nickel-metal hydride (NiMH) batteries, they still don't offer enough energy storage to take an EV much further than 100 miles without a lengthy recharge. Even if the Li-ion batteries were up to the challenge, there is still the awkward problem of where to pack 1,000 pounds (or more) of bulky storage cells into a vehicle's chassis.IBM thinks it has a solution with a promising new lithium-air (Li-air) battery. According to the technology giant, a typical Li-air battery cell has a theoretical energy density more than 1,000 times greater than today's industry-standard Li-ion battery cell. Even better, Li-air batteries are one-fifth the size and they offer a lifespan at least five times as long.So, what has been holding IBM back? It appears that there was a problem with the the original Li-air automotive application, as frequent recharging cycles compromised battery life. However, the engineers have recently found alternative electrolyte compounds that look very promising. The team's goal is to have a full-scale prototype ready by 2013, with commercial batteries on sale by the end of the decade.