Effects of material doping on the performance of thermoelectric generator with/without equal segments

Abstract

Thermoelectricity is a clean energy source that has garnered attention worldwide. Improving the performance of thermoelectric devices to convert waste heat into electricity efficiently is currently a priority for many researchers. One way to do this is by improving the thermoelectric performance of the materials used in thermoelectric generators (TEGs). In recent years, doping different materials into thermoelectric materials to enhance TEG's performance has attracted attention. This study analyzes the improvement of TEGs by performing 3D numerical simulations of thermoelectric devices using a series of SnTe with different doping levels. The results show that the undoped SnTe-AgSbSe2 composite has the highest output power compared with the doped case. In terms of conversion efficiency, the composite AgSbSe2 doped with 3% SnTe achieves the highest conversion efficiency. Furthermore, the performance comparison with conventional TEG shows that the equal segmented thermoelectric generator (STEG) has higher output power and conversion efficiency at all doping ratios. In addition, the SnTe-AgSbSe2 composite with 3% doping concentration has the best thermoelectric performance with an output power of 64.49 mW and an efficiency of 14.17% at a temperature difference of 500 K (a hot side temperature of 800 K and a cold side temperature of 300 K). Accordingly, it is summarized that the combination of doped SnTe thermoelectric material and equal-STEG design can efficiently enhance the thermoelectric module's (TEM) performance.