A thermoelectric generator (TEG) embedded in a wearable wristband can transform body heat into enough electricity to power an LED. Since it can power smartwatches and other wearables, this technology may theoretically eliminate the need for conventional charging devices.
Qian Zhang from the Harbin Institute of Technology in China who has been studying this technology for over 15 years says that “Energy supply is always a big issue, and this could help alleviate the energy crisis.”
TEGs are used in a wide range of applications, however their energy output is normally quite low. This is a major issue that Zhang and his colleagues are attempting to overcome. They layered a magnesium and bismuth material – the TEG materials – between polyurethane and a flexible electrode to create a wristband that could wrap around a human arm.
As a result, the wristband measures 115mm long and is just under 30mm thick. It generates power thanks to the difference between the temperature of human skin and the temperature of the surrounding environment. The unit can produce 20.6 microwatts per square centimetre at its peak, which is more than enough to light an LED attached to the wristband.
If the technology becomes more relevant it may become a stepping stone for the future generations of wearables. As a result, we may experience a future, where all of out gadgetes will be completly wireless and without the need for any charging.
Sources:
https://interreviewed.com/wristband-that-turns-body-heat-into-electricity-can-power-an-led/