Now print batteries on a paper with nanotube ink

Nanotechnology researchers at the University of California have made nanotube ink from the chemicals used in an ordinary battery, thereby making it possible to print batteries onto surfaces like paper.

Washington, November 18 : Nanotechnology researchers at the University of California have made "nanotube ink" from the chemicals used in an ordinary battery, thereby making it possible to print batteries onto surfaces like paper.

Lead researcher George Gruner has revealed that he used the same zinc-carbon chemistry in his batteries as are used in ordinary non-rechargeable batteries.

He believes that the technique to print flexible batteries onto different surfaces may prove helpful in powering disposable devices like long-range RFID tags or small displays.

The batteries, less than a millimetre thick, are made from two layers containing carbon nanotubes and a third layer of zinc foil.

For making the battery, a layer of nanotubes is first deposited in the form of "nanotube ink" onto a surface. The layer acts as the charge collector, which removes current from the battery.

Thereafter, a layer of nanotube ink mixed with manganese oxide powder and electrolytes, which carries charge within the cell, is applied on top, which acts as the cathode. Finally, a piece of zinc foil is applied, which acts as the anode.

"The batteries are similar to conventional batteries, with the electrically conducting nanoscale networks replacing conventional metals and electrodes," New Scientist quoted Gruner as saying.

He further said that the designs should make it possible to get more power than a conventional design would from the same materials, "an important factor for portable electronics applications."

The research team has also developed supercapacitors using the inking technique, and they now plan to combine them with batteries for applications requiring more power.

They have revealed that both printed batteries and supercapacitors can be made entirely at room temperature, which is why it should be possible to mass-produce them using established printing methods.

Nottingham University chemist George Chen agrees that nanotubes may provide ways to improve battery performance.

He, however, says that Gruner's batteries have been tested at low power only.

"The discharge currents are, so far, smaller than needed for practical use," he said.

Gruner, on his part, says that his team is working to increase power output and to demonstrate suitability of the designs for industrial production.

The new technique has been described in the journal Applied Physics Letters.

ANI