The research, which was led by Professor Nikhil Koratkar and initially published in the journal Nano Letters, demonstrated how a “nanoscoop” electrode was able to achieve its faster charge in 100 continuous charge/discharge cycles.
“Charging my laptop or cell phone in a few minutes, rather than an hour, sounds pretty good to me,” said Koratkar in a RPI press release. “By using our nanoscoops as the anode architecture for Li-ion rechargeable batteries, this is a very real prospect. Moreover, this technology could potentially be ramped up to suit the demanding needs of batteries for electric automobiles.”
While this technology could increase the charge/discharge rates of li-ion batteries, I didn’t see any discussion within the coverage of the research whether it will improve the watt-hours of energy per kilogram (Wh/kg), which I noted last month to much criticism Secretary Steven Chu had suggested should reach a level of 1000Wh/kg in electric vehicles to compete with fossil fuels.
At any rate, Koratkar also intriguingly suggests in the piece that the nanoscoop material could enable the bringing together of supercapacitors—used for power-intensive functions such as starting the car—and traditional batteries—that provide high energy density for normal driving—into one single battery unit.
The trick to the nanoscoops capabilities lies in its composition, structure and size. In composition and structure it sounds like a good ice cream cone. They are “made from a carbon (C) nanorod base topped with a thin layer of nanoscale aluminum (Al) and a “scoop” of nanoscale silicon (Si)”.
It is this structure that accounts for the material’s ability to accept and discharge Li ion batteries at extremely fast rates and without causing damage. The layered structure of the nanoscoop transfers strain from the carbon layer to the aluminum layer and then finally to the silicon.
The next steps for the researchers will be to overcome the lack of overall mass of the electrode. They are investigating growing longer scoops or perhaps stacking numerous scoops on top of each other.
Dexter Johnson is a contributing editor at IEEE Spectrum, with a focus on nanotechnology.