Turning A Plain White T-Shirt Into A Not-So-Plain Battery

A new process that lets cotton hold a charge could be the beginning of a world of flexible batteries.

Flexible electronics–from rollup cell phones to bendable laptops–lie just around the corner. But there is one major obstacle in the way of fully bendy gadgets: While we can build screens that bend without breaking, our batteries remain fairly rigid.


That could soon change. The journal Advanced Materials has reported a new way to create cheap, flexible fabrics that store significant amounts of energy. The experiment, led by the University of South Carolina’s Xiaodong Li, showed how a plain cotton T-shirt may also transmit and store energy.

“We wear fabric every day,” says Li, a professor of mechanical engineering at USC, in a university release. “One day our cotton T-shirts could have more functions; for example, a flexible energy storage device that could charge your cell phone or your iPad.”

Li devised a process that “converts insulating cotton T-shirt textiles into highly conductive and flexible activated carbon textiles.” In other words, it changes the fibers that make up the fabric into wires and (energy-storing) capacitors. Li bought a T-shirt at a local discount store, soaked it in a fluoride solution, and heated it in an oxygen-free environment to change the cotton fibers’ cellulose into activated carbon. While this alone was enough to create a conductive material, Li’s team coated the activated carbon fibers with nano-layers of manganese oxide, which boosted the T-shirts performance.

While these new “hybrid fabrics” may not resemble anyone’s former white T-shirts (the process turns it black, for one), the material retains enough flexibility and charge to prove useful as a pliable battery. “By stacking these supercapacitors up, we should be able to charge portable electronic devices such as cell phones,” Li says.

About the author

Michael is a science journalist and co-founder of Publet: a platform to build digital publications that work on every device with analytics that drive the bottom line. He writes for FastCompany, The Economist, Foreign Policy and others on science, economics, and the environment.