Flexible Device Harvests Body Heat to Power Wearable Electronics

There have been no shortage of materials that harvest power from the human body. From generators that produce electricity from the friction or bending of our movements to devices that use the body to form a battery, scientists have been exploring how our everyday existence can lend power to the electronics we rely upon.

Researchers at North Carolina State University have created a device that has the potential to be the best of its kind. The flexible thermoelectric generator not only is capable of producing electricity from body heat, but it is also able to self heal.

The flexibility of the device allows it to be fitted to many more applications, especially when conforming to the human body, but as of yet, flexible thermoelectric devices haven't been able to perform as well as rigid ones.

“We wanted to design a flexible thermoelectric harvester that does not compromise on the material quality of rigid devices yet provides similar or better efficiency,” said Mehmet Ozturk, a professor of electrical and computer engineering at NC State and corresponding author of a paper describing the work. “Using rigid devices is not the best option when you consider a number of different factors.”

They started out by using the same thermoelectric materials that are used in rigid devices so that manufacturing would be simplified. The use of liquid metal to connect the thermoelectric elements, which have a low resistance, increased the power output while also making the device self-healing since the liquid metal can reconnect if a connection is broken.

The researchers plan on continuing to improve the efficiency of the energy harvester, but a future where it could be used to power wearable medical devices and environmental sensors like air quality monitors and more could be right around the corner.