Last year, the battery startup A123 Systems spun out another company, called 24M, to develop a new kind of battery meant to make electric vehicles go farther and cost less. Now a research paper published in Advanced Energy Materials reveals the first details about how that battery would work. It also addresses the challenges in bringing the battery to market.

A big problem with the lithium-ion batteries used in electric vehicles and plug-in hybrids is that only about 25 percent of the battery's volume is taken up by materials that store energy. The rest is made up of inactive materials, such as packaging, conductive foils, and glues, which make the batteries bulky and account for a significant part of the cost.