Energy-generating fabric set to power battery-free wearables
Fri 6 Mar 2015
A team of researchers in Korea and Australia have developed a flexible fabric which generates power from human movement – a breakthrough which could replace batteries in future wearable devices.
The foldable technology incorporates triboelectric nanogenerators (TNGs), and two durable fabrics: a silver-coated textile and another coated in silicon rubber and silver, zinc oxide nanorods approximately 100 nanometres wide and one micron high. The effect of the nanogenerators mirrors static electricity when the two fabrics repeatedly brush against each other and one surface steals electrons from the other – this exchange creates energy from the wearer’s activity without the need for an external power source.
When the research team, led by Sang-Woo Kim, placed four pieces of the fabric on top of each other and pushed down with slight finger pressure, it immediately generated an average of 170 volts and 120 microamperes, and a maximum power of around 1.1 milliwatts.
The lightweight fabric has been found to be extremely durable with the technology still producing electricity after over 12,000 compression and release cycles.
According to the scientists, this ‘smart’ fabric could lead to a number of important uses including the ability to charge wearable devices, such as smartwatches, robotic skin and medical device applications.
“There are numerous ways to enhance the performance of the triboelectric nanogenerator from the materials point of view,” said Zhong Lin Wang, professor at Georgia Tech, in a report published by ACS Nano. “This gives an excellent opportunity for chemists and material scientists to do extensive study both in the basic science and in practical applications.”
During testing, the researchers demonstrated the nanogenerator powering a number of devices such as LEDs, a liquid crystal display, as well as a keyless car entry system embedded in a TNG “power suit”.
The nanotechnology is still in early stages of development and details are yet to been given about future availability.