Slashdot Mirror
A Non-Toxic, Paper Battery / Supercapacitor
jcr writes "Researchers at Rensselaer Polytechnic Institute have developed a combination battery/capacitor by infusing carbon nanotubes and electrolytes into a paper substrate. The material can be folded, rolled up, or molded to any convenient shape with no effect on power capacity. Operating temperature range is -100 to 300 degrees F. One of the co-authors is quoted: 'We're not putting pieces together — it's a single, integrated device. The components are molecularly attached to each other: the carbon nanotube print is embedded in the paper, and the electrolyte is soaked into the paper. The end result is a device that looks, feels, and weighs the same as paper.'" The researchers haven't yet developed a high-volume way to manufacture the devices. They envision ultimately printing sheets between rollers like newsprint.
This is a pointless announcement. Anybody can make a capacitor with two conducting surfaces separated by an insulator. A good, useful, and economical capacitor is something else. Questions like capacitance, capacitance per unit area, capacitance per unit volume, voltage rating, Q, stability, cost per unit, testability, long-term stability and reliability, manufacturability, testability, structural strength, vibration effects, electromigration, overvoltage resistance, pinhole noise, dielectric drift, leakage current, leakage drift, stray inductance, longevity, temperature range, polarization, memory effect, moisture resistance, solvent resistance, altitude effects, and more are significant parameters. A useful new capacitor design would have to have some significant advantages over current designs.
Power capacity. Keith Dawson, it's anything BUT that. Power capacity would be the ability to discharge. The poster is probably thinking of energy density. PLEASE READ THE SUBMISSIONS (and maybe try to understand them if you can) BEFORE YOU POST THEM ON THE FRONT PAGE.
Where are the numbers? As in how many microFarads per cubic centimeter does this material hold? As in how many milliAmp/hours? Without any numbers this is just science fiction, or a slow day at journalism school.