Therein lies the crux of IBM’s Battery 500 project: Current battery tech simply cannot come close to gasoline, which is why we’re surrounded by electric cars that are lumbered down by massive batteries that can only go 100 miles — and why gas still rules supreme. Eventually (in another 10 years or so), li-ion batteries could be replaced with li-air batteries that are a tenth of the size and weight, and yet last just as long — or, of course, li-air could replace gasoline.