Flexible, Stretchable CNT Supercapacitor Could Be Key to Lean, Green Wearables and IoT Networks
Holding the bulk of its capacitance even after 5,000 bending cycles, this flexible supercapacitor is cheaper, greener, and quicker to make.
Researchers at the University of Surrey's Advanced Technology Institute (ATI) and the Federal University of Pelotas (UFPel) have come up with environmentally-friendly flexible supercapacitors that, they say, could prove perfect for boosting the efficiency of everything from wearables to remote sensor networks in the Internet of Things (IoT).
"Supercapacitors are key to ensuring that 5G and 6G technologies reach their full potential," claims Ravi Silva, professor and director of the ATI of the new supercapacitor. "While supercapacitors can certainly boost the lifespan of wearable consumer technologies, they have the potential to be revolutionary when you think about their role in autonomous vehicles and AI-assisted smart sensors that could help us all conserve energy. This is why it's important that we create a low cost and environmentally friendly way to produce this incredibly promising energy storage technology."
That is precisely what the researchers claim to have developed: a wafer-thin supercapacitor that retains most of its capacitance even after repeated bending and stretching cycles, and which can be produced more quickly, for less money, and with a lower environmental impact than its rivals.
The compact capacitor is constructed from aligned carbon nanotube (CNT) arrays, which are constructed on a silicon wafer then transferred to a matrix of polydimethylsiloxane (PDMS). This is in turn coated in polyaniline (PANI), a "pseudocapacitor," resulting in a low-cost supercapacitor that can flex and stretch without failing.
In testing the prototype supercapacitors were show to offer an energy density of 20μWh/cm⁻² at a power density of 100μW/cm⁻², and to retain 76 per cent of its maximum capacitance and 80 per cent of its electrochemical properties after 5,000 bending cycles.
The team's work has been published in the journal Nanoscale under closed-access terms; no discussion has been made public regarding commercialization.
Main article image courtesy of the University of Surrey.