High-Power-Density Wearable Thermoelectric Generators for Human Body Heat Harvesting

Abstract

Wearable thermoelectrics has attracted significant interest in recent years. Among them, rigid-structure thermoelectric generators (TEGs) were seldomly employed for wearable applications, although those exhibit significant advantages of high device output performance and impact resistance. Here, we report a type of rigid wearable TEGs (w-TEGs) without ceramic substrates made using a simple cutting-and-bonding method. Owing to the small contact area, the w-TEGs comprising 48-n/p-pairs can be well attached to the human body. The lack of ceramic substrates leaves more space in the height direction, which benefits the wearability in practical applications and high power density. We demonstrated that increasing the height of w-TEGs from 1.38 to 3.14 mm significantly improves the power density by a factor of 10. As a result, the maximum power densities of 7.9 μW cm −2 and 43.6 μW cm −2 for the w-TEGs were realized under the breezeless condition and a wind speed for normal walking, respectively. This work provides a feasible design solution for rigid-structure free-substrate w-TEGs with very high power density, which will speed up the research of wearable thermoelectrics.

High‐Performance Stretchable Thermoelectric Generator for Self‐Powered Wearable Electronics

“…In brief, high‐performance Bi 2 Te 3 ‐based TE materials were repeatedly cut and bonded to obtain a 3D n‐p array. [ 33 , 41 ] The Au layers were subsequently deposited by a radio frequency (RF) magnetron sputter to join the p‐ and n‐pairs in a series circuit. Finally, the TE unit was achieved after the electrochemical deposition of Ni on the Au layers to reduce the resistance of the electrodes.…”

“…Bulk Bi 2 Te 3 ‐based alloys, the only commercialized TE materials, [ 22 , 23 , 24 ] have generally been employed as TE legs in wearable TEGs, [ 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 ] which however are naturally brittle near room temperature. To realize the wearability of electronic devices, the brittle Bi 2 Te 3 ‐based TE legs are generally encapsulated in flexible substrates, [ 25 , 26 , 27 , 28 , 29 ] such as polydimethylsiloxane (PDMS) and Ecoflex.…”

Recent Advances, Opportunities, and Challenges in Developing Nucleic Acid Integrated Wearable Biosensors for Expanding the Capabilities of Wearable Technologies in Health Monitoring

“…To improve the biosensor’s sustainability over an extended period of time, there is a need to design self-powering biosensors and implement energy harvesting mechanisms into their wearable biosensing devices [ 55 ]. There have been efforts to develop triboelectric or thermo-electric power generators that utilize bodily functions to generate power for wearable devices [ 56 , 57 ]. However, output signals with higher noise, as well as low power output, might inhibit the usage of some transduction and readout mechanisms, such as electrochemical or electrical devices.…”

High-Performance Wearable Bi2Te3-Based Thermoelectric Generator

“…Furthermore, wearable thermoelectric generators (w-TEGs) have been studied by many scholars [18][19][20][21][22]. Fan et al [23] used a simple cutting and gluing method to fabricate a w-TEG containing 48 pairs of P/N thermoelectric cells while without a ceramic substrate. The w-TEG can be well attached to the human body, and the maximum power density of w-TEG was 7.9 μWcm −2 and 43.6 μWcm −2 under windless and normal walking conditions, respectively.…”