Phone-charging jacket, power-storing fitness sleeves, or medical sensors free from bulky batteries are all becoming realities thanks to a new class of flexible, fibre-shaped supercapacitors made from carbon nanotubes.
Among the cutting-edge insights presented in the book Electrochemical Energy Storage Materials, a standout chapter explores how carbon nanotube (CNT) fibres are being spun into the future of wearable energy. The technology may sound technical — and it is — but its potential is easy to grasp: make energy storage stretchable, breathable, and light enough to wear.
From Charcoal to Carbon Nanotubes: A Big Leap in Tiny Fibres
Traditional energy storage, like lithium-ion batteries, is compact but rigid. Supercapacitors — which store energy by building up charge layers instead of through chemical reactions — offer faster charging, better durability, and greater safety. But their drawback has been lower energy density.
Enter carbon nanotubes, tiny cylinders of carbon atoms with phenomenal strength, flexibility, and conductivity. When these are spun into thin fibres (like yarn), they become:
- Highly conductive
- Stretchable
- Lightweight
- Mechanically strong
And crucially, they can be woven directly into fabrics.
Power That Moves With You
A major breakthrough described in the book involves coaxial spinning — a clever technique where a CNT core is wrapped in a protective outer layer during spinning. Researchers found that this structure helps the fibres store more energy without short-circuiting, while also improving ion transport (essential for recharging).
When these CNT fibres are combined with pseudocapacitive materials like MnO₂ or conducting polymers, they perform even better. One test fibre produced a capacitance of 177 millifarads per square centimetre — a record-breaking level for such a small device. Even after 10,000 charge–discharge cycles, the fibres retained their power.
That’s the kind of durability needed for real-world use: imagine gym gear that powers your headphones, or a smartwatch strap that charges from your body heat and motion.
Built to Flex, Not Fail
One major advantage of these fibre-based supercapacitors is their resilience:
- They can bend, twist, and stretch without losing performance
- They remain safe — no liquid electrolytes to leak or ignite
- They’re scalable, meaning they can be made long enough for weaving and knitting
Tests with added materials like platinum nanoparticles and polyaniline polymers enhanced their conductivity and power output, paving the way for high-performance, low-cost energy textiles.
Important Implications for the North
These are regions where cold weather and long winters put stress on energy systems — and personal electronics. Portable, body-warmed power storage could reduce dependence on bulky external batteries. What’s more, breathable and lightweight power fabrics would suit outdoor work, emergency services, healthcare, and even winter sports.
And as countries shift toward circular, wearable tech and off-grid resilience, this research offers a promising path: energy devices that fit into our clothing and our lives — not the other way around.
Still Experimental — But Not for Long
Right now, carbon nanotube fibre supercapacitors are mostly in the lab. But production methods are advancing fast, including wet spinning, dry spinning, and twisting, allowing researchers to control fibre shape, strength, and performance.
The next steps involve:
- Lowering production costs
- Scaling up fibre lengths
- Improving energy density to rival small batteries
- Integrating with real garments and consumer tech
Overcoming these hurdles clears the way to your coat being smarter, warmer, and more powerful.
Source
Carbon Nanotube Fiber-Based Wearable Supercapacitors—A Review on Recent Advances, Energies, 2025-03-05
Boˆreal 