High efficient personal thermoregulatory device: Metallized interface layer between flexible polyimide substrate and foam copper heat sink enables thermal resistance reduction

Abstract

Customizable flexible thermoelectric devices (f-TED) designed for personal thermal management (PTM) have the potential to substantially diminish energy consumption while enhancing comfort. Currently, studies focus on optimizing thermoelectric device performance and reducing radiator thermal resistance, neglecting the crucial interface between them. In this innovative work, the interface layer between the flexible polyimide substrate of f-TED and the foam copper heat sink was metallized, thereby significantly mitigating the thermal resistance at the interface. In contrast to the conventional thermal conductive adhesive, the metallized welding thermoelectric system (4 × 4 cm² in the plane) demonstrates a 37.0 % augmentation in cooling temperature difference (5.4 ℃ → 7.4 ℃) at 0.3 A. When bending 1000 times (r: ∞ → 20 mm → ∞ → …), the change rate of internal resistance is less than 1.5 %. At a temperature difference of 20 K, it reaches a maximum output power as high as 4.45 mW. Furthermore, an intelligent personal thermal management system was developed. Users can monitor and adjust the working status of the f-TED in real-time via a mobile terminal, achieving personalized thermoregulation. In actual human wear tests, the highest cooling temperature difference reached 13.7 °C, which is one of the highest reported values. This work holds significant implications for advancing f-TED technology innovation, personalized thermoregulation, energy conservation, and environmental protection.