Improving the performance of TEM embedded with paraffin-based phase change materials with different thermal conductivity

Abstract

In this work, the effect of thermal conductivity of phase change materials (PCMs) on the performance of thermoelectric module (TEM) was studied. Paraffin wax composites with different mass fractions (0%, 0.5%, and 1.5%) of carbon nanotubes (CNTs) were used for heat storage in the experiments. The experimental results show that PCM with high thermal conductivity have remarkable effects on improving the power generation of the TEM. Compared to the TEM without PCM, through increasing the thermal conductivity of PCM, the maximum electrical energy generated by TEM increased by 34.9%. Besides, through increasing the height and diameter of the embedded PCM, the effective length of the TEM was optimized and the heat storage of the PCM was increased. As a result, the output voltages of the TEM with PCM were increased 0.3–0.5 mV compared to those of the TEM without PCM. Specifically, the TEM (marked as “1.5%CNT-d30h8”) embedded with PCM with the highest thermal conductivity and the largest geometric dimension can generate a maximum of electrical energy and reach 372.1 mJ.