A team of Stanford researchers is producing batteries and simple capacitors from ordinary textiles dipped in nanoparticle-infused ink. The conductive textiles – dubbed “eTextiles” – represent a new class of integrated energy storage device, born from the synthesis of prehistoric technology with cutting-edge materials science.

“We have been developing all kinds of materials, trying to revolutionize battery performance,” said Yi Cui, assistant professor of materials science and engineering at Stanford. “Recently, we started to think about how to make batteries in a very different way from before.”

How would you like it if your phone started charging whenever you dropped it into your pocket? That may eventually be possible, thanks to a carbon nanotube-based ink that can turn many common fabrics into conductors, or even components of a charge-storing supercapacitor. These won’t be showing up in a clothing store near you anytime soon, however, as ensuring that the fabrics only direct the charge to appropriate devices and not, say, to a sensitive body part will be a separate engineering challenge.