Ranjan Dash

Problem: Ultracapacitors, which last longer than conventional batteries and can deliver stronger bursts of power, hold great promise as energy-storage devices for applications such as hybrid electric vehicles. But ultra­capacitors typically can't store as much energy as batteries, so they need to be recharged frequently. That drawback has limited their use.

Solution: As a graduate student in materials science at Drexel University, Ranjan Dash used a novel chemical recipe to engineer nanoscopic pores into the carbon materials used in ultracapacitors. The tiny pores, whose size can be tuned with subnanometer precision, provide more surface area for charged particles to stick to, doubling the amount of energy the ultracapacitors can hold. Dash cofounded Y-Carbon, a startup based in King of Prussia, PA, to commercialize the technique, and he now serves as its chief technology officer. He says that his company has already developed a prototype ultracapacitor. The plan is to partner with other companies to develop this and other applications for the porous material, which Y-Carbon will manufacture. The first ultracapacitor products could be on sale in about two and a half years, Dash says. --Neil Savage