By weaving photoanodes and triboelectric nanogenerators into cloth, researchers have created a "hybrid power textile."
Someday, your clothing could power your smart watch, your fitness tracker, or other small wearable devices if the results of some new research at Georgia Institute of Technology are any indication.
The more gadgets we have, the more need we have for portable power sources, and yet for the most part, it seems as if the tech industry is more focused on building better batteries than in integrating energy harvesting components into mobile devices. While there's no doubt that advancements in battery technology will continue to have an impact on just a number of facets of modern life, from electric mobility options to medical devices to personal electronics, having a way to recharge those batteries while on the go is another way to approach the issue of portable power. Mounting small thin solar cells onto items such as backpacks or clothing has been tried with some success, but in the end, those items still look like they've had solar added to them, which is not desirable.
But what if we could build that capability into something we're surrounded by every day, such as textiles, and do so in such a way as to not appear that different from any other piece of clothing? That day may be coming, at least for smaller gadgets with low power demands, thanks to the work of a team of researchers at the Georgia Tech School of Materials Science and Engineering.
The team, led by Zhong Lin Wang, a professor at Georgia Tech, has successfully woven a new type of fabric, which they refer to as a "micro-cable power textile," that integrates photoanodes (solar cells made from lightweight polymer fibers) and triboelectric nanogenerators (which are able to generate small amounts of electricity from motion), in essence creating a fabric capable of producing electricity. The new textile, which was woven together with wool strands, is 320 micrometers thick and is said to be "highly flexible, breathable, light weight and adaptable to a range of uses."
"This hybrid power textile presents a novel solution to charging devices in the field from something as simple as the wind blowing on a sunny day." - Zhong Lin Wang, Georgia Tech School of Materials Science and Engineering
According to Georgia Tech, the team used a piece of fabric about the size of a standard sheet of paper, and then attached it to a rod, similar to how a flag is mounted. The textile 'flag' was then allowed to blow in the wind while being driven in a car with the windows down, which generated "significant power," even on a cloudy day. The output of a 4 cm x 5 cm piece of the power textile was said to be capable of charging a 2 microfarad capacitor to 2 V in one minute from motion and sunlight, essentially showing "a decent capability of working even in a harsh environment."
"The backbone of the textile is made of commonly-used polymer materials that are inexpensive to make and environmentally friendly. The electrodes are also made through a low cost process, which makes it possible to use large-scale manufacturing." - Wang
Although these results point to the potential for viable power generation from future textiles, the team is still working on improving its durability over the long term, as well as optimizing it for industrial purposes, including developing ways to protect the electrical components in it from moisture. The team published their findings in the journal Nature Energy under the title "Micro-cable structured textile for simultaneously harvesting solar and mechanical energy."