Researchers from North Carolina State University have discovered a solution to prevent electrical faults in yarns that have been designed to store electrical energy. The results, published in a recent study, may eventually aid in the creation of “smart textiles” that gather energy from the wearer’s movements and incorporate power sensors and wearable technology.
Yarn-shaped supercapacitors (YSCs) are becoming promising energy-supply units with decent mechanical flexibility to be integrated into e-textiles in various shapes and locations. However, a robust YSC configuration that can provide long-term and reliable power output, especially after rigorous weaving and knitting processes and all kinds of end uses, is yet to be established. Most YSCs today still suffer from short-circuiting upon length, primarily due to the structural failure of the gel electrolyte that works as the separator. The researchers have reported incorporating separator threads in a twisted YSC to withstand repetitive mechanical deformations.
Separator threads are wrapped outside of yarn electrodes as a scaffold to accommodate gel electrolytes while these threads’ chemistry and wrapping density are investigated. With processing parameters optimized, researchers present a YSC configuration that can bear mechanical deformations in almost all directions, leading to reliable power units in woven or knit fabrics.
In brief, to address this issue, the researchers investigated what would happen if the supercapacitor yarn electrodes were coated in insulating threads. The threads were supposed to operate as a physical barrier, preventing short-circuiting by prohibiting the opposing electrodes from touching each other. By attaching the electrodes to a power supply and recording the device’s latest response, they could assess its performance. They also put the yarns to the test to see how well they could hold a charge. After charging and discharging the yarns 10,000 times, researchers discovered that they retained 90% of their initial energy. This could benefit the world of smart textiles, where the short circuit could damage the wearer or surroundings.
