In the coming decades, hybrids, and maybe even all-electric vehicles, may cruise without batteries. Instead, the energy in these vehicles of the future will be stored in a supercapacitor which could be recharged in minutes, possibly seconds. We've heard of the potential of supercaps (and ultracapacitors) before, but researchers have just announced they've overcome an obstacle to this device development. In the lab, they have developed supercaps with an energy density equivalent to that found in the nickel metal hydride (NiMH) batteries used in hybrids today. Using more technical language, they claim a nano graphene-based, ionic liquid-enabled supercapacitor has achieved a specific energy density of 85.6 Wh/kg at room temperature. I'm sure I speak for all of us here at ABG when I say, "Wowsa!"
The team, consisting of members from Nanotek Instruments, Angstron Materials and the Dalian University of Technology in China, originally discovered that graphene sheets could be used as a supercapacitor electrode back in 2006. However, the one-atom thick material had a tendency to "restack" itself, which interfered with the necessary ionic fluids (of course!). The researchers have now learned that by using curved graphene sheets instead of the original flat sheets, that problem is avoided and capacitance is greatly improved.
*UPDATE: We reached out to Bohr Jang of Nanotek Instruments for further information. He speculates commercialization could happen within three years. They also hope to improve the energy density to 100-150 Wh/kg.
[Source: Physics World]