A “candy cane” polymer being developed could weave power for future functional fabrics and devices.
Researchers from the U.K.’s University of Cambridge report they’ve developed a new material by weaving two polymers together in a way that vastly increases charge storage capacity.
The material is intended for use in products such as self-drying apparel and implantable artificial organs that require flexible, long-lasting batteries.
“We had been developing polymer networks for a different application involving actuation and tactile sensing,” Tiesheng Wang, a graduate student in the lab of Dr. Stoyan Smoukov at Cambridge, said. “After the project, we realized that the stretchable, bendable material we’d made could potentially be used for energy storage.”
Lithium-ion batteries have been most apparent in the energy storage landscape, but the chemical reactions in the charging and discharging process are slow, which limits how much power they can deliver, Cambridge said. They also tend to degrade over time, requiring replacement.
In answer to that, Smoukov and Wang developed a more robust material by weaving together a conducting polymer with an ion-storage polymer. The two polymers were stitched together to form a candy cane-like geometry, with one polymer playing the role of the white stripe and the other one the red. One polymer conducts electricity and the other can store ions. The interwoven geometry is instrumental to the energy storage benefits, Wang said, as it allows the ions to access more of the material overall, approaching the “theoretical limit.”
When tested, the candy cane supercapacitor demonstrated improved flexibility and cycling stability. It also had nearly double the specific capacitance compared to conventional supercapacitors.
But the researchers said there’s room for improvement and they have plans to conduct more experiments to get there. The aim is to create lighter batteries with the same energy storage that can be charged faster, which is an important consideration in the development of novel wearables, robots and other devices, Smoukov noted.
Research into smart textiles is ongoing and the sector is one with a host of potential.
Teijin Limited, a technology-driven high-performance fiber manufacturer, and Kansai University recently created wearable braided cord sensors that could integrate into clothing to remedy issues associated with some conventional wearable sensors, including adaptability and usage.
The research was presented this week at a meeting of the American Chemical Society. The Cambridge study receives funding from the European Research Council, the China Scholarship Council and the U.K. Center for Doctoral Training in Sensor Technologies and Applications of the Engineering and Physical Sciences Research Council.