Stanford Researchers Turn Fabrics into Batteries

Carbon nanotubes on fabric fibers

Stanford University nanomaterials science and engineering professor Yi Cui and a team of researchers have demonstrated a technique for using a special “ink” made of carbon nanotubes that can successful convert ordinary cotton and polyester fabric into flexible batteries that function when when their folded and twisted. The research, published in Nano Letters, uses an “ink” made of single-walled carbon nanotubes; fabrics are dipped in the ink, and the nanotubes align along the fabrics existing fiber. Once dried, the material retains its flexibility and stretchability while still remaining highly conductive—further, the researchers demonstrated loading the fabric with psuedocapacitor materials that increased the fabric’s areal capacitance by 24 times. The research offers new directions for wearable electronics, and even fabrics that can act as batteries to power high-tech gizmos.

“The ideal wearable power would incorporate textile as a component,” the researchers wrote. “The fabrication process is simple and scalable, similar to those widely used for dyeing fibers and fabrics in the textile industry.”

The nanotube-inked fabrics even maintains its conductive properties when washed in water and wrung out, meaning the technology may be practicable for everyday use.

The next steps in the research are to incorporate materials that enable fabrics to store more energy, in order to serve as more-useful batteries—by combining the nanotubes with other materials, the researchers speculate that garments that function as wearable solar cells might even be possible.

[Image credit: Stanford University/Nano Letters]