Investigation on the structural design and performance optimization of micro Y-type thermoelectric devices utilizing flexible electrical connections of liquid metal

Abstract

Microscale thermoelectric generators (TEGs) have garnered significant attention due to their potential applications in the Internet of Things (IoT) devices, particularly in wearable and medical monitoring equipment. The cross-plane Y-shaped structure demonstrates superior performance compared to the π-shaped structure, yet its application is limited by the complexities in manufacturing processes and structural research. Traditional copper ingots were replaced with the liquid metal EGaIn (Eutectic Gallium-Indium) as an electrical connecting element, effectively addressing contact issues during flexible bending and optimizing circuit transmission. Finite element modeling was utilized to conduct an optimization analysis of the Y-shaped structure, revealing its complex thermal conduction characteristics and predicting device performance. Under a temperature difference of 20 K, the power density of the Y-shaped thermoelectric generator is approximately 4 μW/cm², with the optimized structure exhibiting a 231 % increase in output power density compared to the original structure.