The search for a better battery is endless. The underlying physics present limitations that are hard to surpass, but there’s seemingly no end to human ingenuity when it comes to finding new ways of storing electrical energy. Try this one: Scientists at Stanford University (California, USA) have created an ink compounded with nanotechnology materials, dipped a piece of ordinary paper in it, and voila! (or Presto! If you prefer) it can store an electrical charge.

To give the research more due to it, the issue here is less competition with standard batteries and more like building a more efficient capacitor, in fact, a super-capacitor. Capacitors are components used in almost every electrical device to briefly store, modulate, or filter a flow of electricity.

Stanford scientists are harnessing nanotechnology to quickly produce ultra-lightweight, bendable batteries and supercapacitors in the form of everyday paper. Simply coating a sheet of paper with ink made of carbon nanotubes and silver nanowires makes a highly conductive storage device, said Yi Cui, assistant professor of materials science and engineering. “Society really needs a low-cost, high-performance energy storage device, such as batteries and simple supercapacitors,” he said.

Like batteries, capacitors hold an electric charge, but for a shorter period of time. However, capacitors can store and discharge electricity much more rapidly than a battery. Cui’s work is reported in the paper “Highly Conductive Paper for Energy Storage Devices,” published online this week in the Proceedings of the National Academy of Sciences.

“These nanomaterials are special,” Cui said. “They’re a one-dimensional structure with very small diameters.” The small diameter helps the nanomaterial ink stick strongly to the fibrous paper, making the battery and supercapacitor very durable. The paper supercapacitor may last through 40,000 charge-discharge cycles – at least an order of magnitude more than lithium batteries. The nanomaterials also make ideal conductors because they move electricity along much more efficiently than ordinary conductors, Cui said.

[Source: Stanford University]