Design and single/multi-objective optimization of N-type Skutterudite/P-type half-Heusler-based thermoelectric modules based on an improved thermal resistance model

In order to solve the problem of poor output and stability of Skutterudite-based(SKD) thermoelectric(TE) modules caused by slow development of P-type SKD materials, an N-SKD/P-half-Heusler(HH) module scheme is proposed in this paper. An improved thermal resistance model is established to predict the performance of the module, and the model is proved to be reliable. The relationship between the performance of the module and the proposed two dimensionless structure parameters is studied. The results show that the N-SKD/P-HH scheme can effectively improve the output performance of TE modules. The maximum output power(P) of N-SKD/P-SKD, N-SKD/P-HH(ZrCoSb), and N-SKD/P-HH(NbFeSb) TE modules were obtained with single-objective optimization to be 1.31 W, 2.18 W, and 2.76 W, respectively, and the maximal conversion efficiency(η) of the three TE modules were 10.78%, 11.15%, and 12.01%, respectively. Multi-objective comprehensive performance optimization shows that relative to the conventional N-SKD/P-SKD, the N-SKD/P-HH(ZrCoSb) can improve P and η by 66.03% and 1.74%, and the N-SKD/P-HH(NbFeSb) can improve them by 110.91% and 6.24%. In addition, the TE module designed in this paper has high reliability and stability favorable for applications. Therefore, this study can effectively and feasibly guide the research of TE modules and provide useful insights for studying the properties of TE modules.