Beltrán-Pitarch Braulio, García-Cañadas Jorge
Department of Industrial Systems Engineering and Design, Universitat Jaume I, Campus del Riu Sec, Castelló de la Plana 12006, Spain.
ACS Appl Electron Mater. 2021 Nov 23;3(11):4803-4808. doi: 10.1021/acsaelm.1c00670. Epub 2021 Nov 12.
In recent years, thermoelectric (TE) devices have been used in several refrigeration applications and have gained attention for energy generation. To continue the development of devices with higher efficiency, it is necessary not only to characterize their materials but also to optimize device parameters (e.g., thermal contacts). One attempt to increase the efficiency at the device level consists of the replacement of the typical ceramic layers in TE modules by metallic plates, which have higher thermal conductivity. However, this alternative device design requires the use of a very thin electrical insulating layer between the metallic strips that connect the TE legs and the outer external layers, which introduces an additional thermal resistance. Impedance spectroscopy has been proved to be useful to achieve a detailed characterization of TE modules, being even capable to determine the internal thermal contact resistances of the device. For this reason, we use here the impedance method to analyze the device physics of these TE modules with outer metallic plates. We show for the first time that the impedance technique is able to quantify the thermal contact resistances between the metallic strips and the outer layers, which is very challenging for other techniques. Finally, we discuss from our analysis the prospects of using TE modules with external metallic plates.
近年来，热电（TE）器件已被应用于多种制冷应用中，并在能量产生方面受到关注。为了持续开发更高效率的器件，不仅有必要对其材料进行表征，还需要优化器件参数（例如热接触）。在器件层面提高效率的一种尝试是用具有更高热导率的金属板取代TE模块中的典型陶瓷层。然而，这种替代的器件设计要求在连接TE腿和外层的金属条之间使用非常薄的电绝缘层，这会引入额外的热阻。阻抗谱已被证明有助于实现对TE模块的详细表征，甚至能够确定器件的内部热接触电阻。因此，我们在此使用阻抗方法来分析这些带有外部金属板的TE模块的器件物理。我们首次表明，阻抗技术能够量化金属条与外层之间的热接触电阻，而这对其他技术来说极具挑战性。最后，我们从分析中讨论了使用带有外部金属板的TE模块的前景。
