LAUSR

Abstract High thermoelectric figure of merits have been achieved in lead telluride (PbTe) alloys recently, which are beneficial for future thermoelectric applications. In this study, a PbTe-based thermoelectric module is constructed by eight pairs of p-type PbTe–8%SrTe and n-type PbTe0.998I0.002–3%Sb legs with initial sizes of 3 × 3 × 3 mm3. The relationship between multiple geometric parameters and performance of module has been studied by finite-element simulation. The maximum output power (Pmax) of 7.6 W and efficiency (ηmax) of 15.3% have been achieved at ΔT = 500 K for ideal contacted PbTe-based thermoelectric module. Contact resistance must exist in experimental thermoelectric module, so it has been considered in simulation about geometry optimization. The cross-sectional area ratio (Ap/An) and height (H) show strong dependent relationship to optimize module performance. The larger Ap/An and relatively lower H are propitious to enhance the output power. Moreover, the efficiency is improved at an optimum Ap/An and relatively higher H. In this PbTe-based module, the Pmax = 4 W is achieved at Ap/An = 1.78 and H = 0.65 mm, while ηmax = 14% is achieved at Ap/An = 1.64 and H = 13 mm under ΔT = 500 K. The Pmax and ηmax are 20% and 65% larger than those of initial design sizes. Thus, geometric structure modification is a good way to improve the performance of thermoelectric applications.