Boffins in America have developed a "one-dimensional" nanomaterial liquid which can be painted onto walls or pieces of paper to create working batteries.
"If I want to paint my wall with a conducting energy storage device, I can use a brush," says Yi Cui, materials engineering prof at Stanford.
"These nanomaterials are special," he adds. "They're a one-dimensional structure with very small diameters."
Cui's electro-paint can be used as an electrode in other devices, or as a battery or supercapacitor in its own right. As a battery, its energy/weight ratio isn't very impressive - just 7.5 watt-hours/kg when "weight of all of the dead components is considered", or 30-47 Wh/kg on its own, still less than typical lead-acid jobs.
On the other hand, the paint can handle very rapid discharge rates, 200 kilowatts/kg, and CUI says it's very durable too; able to stake 40,000 charge/discharge cycles, maybe ten times as much as a normal li-ion job.
The rapid discharge in particular could be useful in applications like electric or hybrid vehicles, which often need to put out energy very fast for brief periods. This kind of capability could also be useful on the power grid, as it could let storage facilities cope with the often very rapid changes in output from wind or solar generating facilities.
"This technology has potential to be commercialized within a short time," says Peidong Yang, chemistry prof at Berkeley. "It's nanotechnology related to daily life, essentially."
Cui and his colleagues' research is published in the Proceedings of the National Academy of Sciences, here. ®