POWER PAPER

Another of the exciting new ideas that might very well never go anywhere or, on the other hand, might save the world.

Power Paper: Energy Storage By The Sheet; By surrounding carbon nanotubes with cellulose, researchers have devised a flexible, paper-thin power source
David Biello, August 14, 2007 (Scientific American)

WHO
Rensselaer Polytechnic Institute (R.P.I.), biological and chemical engineer Robert Linhardt,

WHAT
3 RPI labs have combined to formulate a material that is also a battery composed of cellulose, carbon nanotubes and an electrolytic liquid.

schematic representation (click to enlarge)

WHEN
Presently a prototype.

WHERE
RPI is in Troy, NY. Experiment results published in Proceedings of the National Academy of Sciences USA.

WHY
- The product of 3 labs: biopolymers, nanotubes and electronics.
- Cellulose soaked in an electrolytic ionic liquid and separating aligned carbon nanotubes (which are the electrodes in the “battery”) dries in thin sheets of “nanocomposite paper” which can be rolled, twisted, bent, cut, stacked and works at high temps.

- It serves as a battery or supercapacitor or both, depending on composition and processing. Test results so far, with 1-inch squares: 1.5 kilowatts/kg as supercapacitor for 100 cycles of charge/discharge (current commercial capacitors: 1 million cycles). With large scale rollouts off printing presses, much larger durations are anticipated.
- It can absorb ionic bodily fluids (sweat, blood) to function.

It's a battery...it's paper...a battery...paper...(click to enlarge)

QUOTES
- Linhardt: "We have a paper battery, supercapacitor and battery-supercapacitor hybrid device that could be used in a variety of energy storage applications…These devices are lightweight and flexible and are primarily composed of cellulose paper—an environmentally friendly and biocompatible material…The nanotubes on which the cellulose is cast contact the paper at the molecular level with an enormous surface area, allowing the device to efficiently store and release power…”
- Linhardt: “The use of these electrolytes based on bodily fluids suggests the possibility of the device being useful as a dry body implant…We are very interested in the possibility of disposable paper defibrillators as a potential medical application."
- Linhardt: "We are realistic enough to recognize that actual scale up of a process can be fraught with unanticipated difficulties…[but] we do not see any insurmountable challenges."