Korean researchers have developed a high-performance flexible thermoelectric device that operates on body heat alone, without the need for a battery. This device can be used to power wireless wearable electronic devices.

On the 20th, the Korea Research Foundation announced that Professor Yong-Taek Hong's research team (Seoul National University) Dr. Seung-Joon Jung's research team (KIST) have jointly developed a thermoelectric device that can self-generate power using body heat alone, enabling the operation of wireless wearable electronic devices without a battery.

A thermoelectric device is a component that converts thermal energy into electrical energy through the Seebeck effect. The Seebeck effect refers to the phenomenon where a potential difference is generated across a closed circuit, leading to a current flow when heat is applied to one junction after joining the ends of different metals. Flexible thermoelectric devices, which can be attached to human skin, received attention as a new power supply component for implementing battery-free, self-powered wearable devices that operate using body heat.

However, existing flexible thermoelectric devices have limited practicality due to their high internal resistance, which leads to little power being generated. To achieve a high-performance flexible thermoelectric device capable of operating external devices, it is necessary to address the main factors that increase the internal resistance of flexible thermoelectric devices, which consist of interfacial resistance between the flexible electrode and thermoelectric material and the electrical resistance of the flexible electrode.

By targeting the two factors, the newly developed flexible thermoelectric device has an internal resistance that is more than six times smaller compared to previous designs. Moreover, it was able to operate a wireless self-powered wearable system that enables Bluetooth communication by itself, thereby allowing the device to power a system that sends rescue requests during emergency situations.

Professor Yong-Taek Hong stated, "This research is significant because it addressed the low power generation issue, which was considered a technical limitation of existing flexible thermoelectric devices, and improved the practicality of flexible thermoelectric devices by enabling the operation of wireless wearable devices with minimal thermal energy, such as body heat." He further mentioned, "The research is expected to greatly contribute to the commercialization of battery-free self-powered wearable devices."

The results of this study were published as a cover paper of ACS Energy Letters on the 9th of last month.

Reference:
ACS Energy Letters, DOI : https://doi.org/10.1021/acsenergylett.3c00243

Source: https://ee.snu.ac.kr/community/news?bm=v&bbsidx=53719

Translated by: Do-Hyung Kim, English Editor of the Department of Electrical and Computer Engineering, kimdohyung@snu.ac.kr