Novel structural design of wearable thermoelectric generator with vertically oriented thermoelements

Abstract

Energy harvesting technology has become important for wearable electronics, where a continuous power supply is essential. Although a wearable thermoelectric generator (TEG) is a promising option in this context, maintaining a substantial temperature gradient (ΔT) between the hot and cold sides of the TEG and a low thermal contact resistance between the TEG and the human body is challenging due to its structural configuration. Herein, a novel structural solution to these problems has been presented with vertically aligned p-type poly (3,4-ethylene-dioxythiophene):poly (styrene sulfonate) (PEDOT:PSS) thin film and n-type aluminum wire-based thermoelements integrated wearable TEG. The developed wearable TEG with five pairs of thermoelements reported an open-circuit voltage (Voc) of up to 1.46 mV when applied to the wrist. Subsequently, the generator was tested at a higher temperature, and the characterization results revealed that the TEG produced a maximum Voc of 5.15 mV at a ΔT of 80 °C. Inclusively, the TEG provided a maximum output power and an output power density of ∼2.4 nW and 1.5 nWcm−2, respectively, at a ΔT of 80 °C. The proposed TEG design concept demonstrates elevated performance with great flexibility and has the potential to act as a viable alternative for next-generation energy harvesting devices.