Researchers cut and assembled tiny solar cells on thin, flexible circuit boards before sealing them in a protective polymer to create a fiber-like strand that was woven with nylon into a small textile. (Credit: Johns Hopkins APL/Ed Whitman)

Researchers from the Johns Hopkins Applied Physics Laboratory, in Laurel, have established scalable methods of developing battery- and solar-powered fibers, making it theoretically possible for electrical energy to be harvested from, and stored in, clothing.

These fibers could power high-performance wearable electronics that breathe, stretch and wash like conventional textiles. Now, in a study published May 22 in Advanced Materials Technologies, APL scientists have demonstrated a novel method to scale up fiber battery fabrication.

Rather than using textile equipment, the APL team customized battery equipment to achieve the thinness required for fiber batteries. This strategy, including the creation of customized roll-to-roll setups, made the process portable and suitable for large-scale production. All the equipment needed to create the fiber batteries could fit in a small room.

This development in fiber power sources — submillimeter-thin battery and photovoltaic strands that could be woven directly into fabrics — opens up a new world of wearable electronics and smart textiles. Instead of carrying a heart monitor with bulky batteries, a patient could wear a shirt that has battery- and solar-powered fibers knit into it; fiber-powered clothing could be heated to keep a person warm in cold environments or laced with battery- and solar-powered fibers to provide soldiers with hands-free audio and video recording in the field.

“As demands for electronic textiles change, there is a need for smaller power sources that are reusable, durable and stretchable,” said Konstantinos Gerasopoulos, assistant program manager for physics, electronic materials and devices at APL and lead investigator of this project. “Our vision is to develop solar harvesting fibers that can convert sunlight to electricity and battery fibers that can store the generated electricity in the textile.”