Fluoride finally has a use: it makes awesome flexible batteries!

(NaturalNews) Researchers at a lab at Rice University are inching closer to flexible, portable and wearable electronics after creating a thin film for energy storage.

A team led by Rice chemist James Tour has developed a flexible material with nanoporous nickel-fluoride electrodes that are layered around a solid electrolyte to provide battery-like supercapacitor performance that marries the best qualities of a high-energy battery with a high-powered supercapacitor minus the lithium found today in commercial batteries, Science Daily reported, citing the team's research.

The work was detailed recently by the team in the Journal of the American Chemical Society.

'This is not easy to do'

As reported by Science Daily:

Their electrochemical capacitor is about a hundredth of an inch thick but can be scaled up for devices either by increasing the size or adding layers, said Rice postdoctoral researcher Yang Yang, co-lead author of the paper with graduate student Gedeng Ruan. They expect that standard manufacturing techniques may allow the battery to be even thinner.

In testing, students found that their one-square-inch device was capable of holding 76 percent of its capacity over 10,000 charge-discharge cycles and 1,000 bending cycles.

Tour said the team sought to find a material with the flexible qualities of graphene, carbon nanotubes and conducting polymers while still possessing much higher electrical storage capacity that is typically found in inorganic metal compounds. Until recently, Tour said, inorganic compounds lacked the required flexibility.

"This is not easy to do, because materials with such high capacity are usually brittle," he said. "And we've had really good, flexible carbon storage systems in the past, but carbon as a material has never hit the theoretical value that can be found in inorganic systems, and nickel fluoride in particular."

Added Yang: "Compared with a lithium-ion device, the structure is quite simple and safe. It behaves like a battery but the structure is that of a supercapacitor. If we use it as a supercapacitor, we can charge quickly at a high current rate and discharge it in a very short time. But for other applications, we find we can set it up to charge more slowly and to discharge slowly like a battery."

As noted by Science Daily:

To create the battery/supercapacitor, the team deposited a nickel layer on a backing. They etched it to create 5-nanometer pores within the 900-nanometer-thick nickel fluoride layer, giving it high surface area for storage. Once they removed the backing, they sandwiched the electrodes around an electrolyte of potassium hydroxide in polyvinyl alcohol. Testing found no degradation of the pore structure even after 10,000 charge/recharge cycles. The researchers also found no significant degradation to the electrode-electrolyte interface.

'Already talking with companies about commercialization'

"The numbers are exceedingly high in the power that it can deliver, and it's a very simple method to make high-powered systems," Tour said, adding that the technique shows promise for the manufacture of other 3D nanoporous materials. "We're already talking with companies interested in commercializing this."

A Rice undergraduate student, Changsheng Xiang, along with post-doctoral researcher Gunuk Wang, are co-authors of the paper.

Rice University said that the Peter M. and Ruth L. Nicholas Postdoctoral Fellowship of the Smalley Institute for Nanoscale Science and Technology and the Air Force Office of Scientific Research's Multidisciplinary University Research Initiative supported the research.

Sources:

http://www.sciencedaily.com

http://news.rice.edu

http://gigaom.com