4. Conclusion

In the present chapter, it has been done an experimental demonstration of the influence of the device legs geometry as well as parasitic electrical contact resistance on ZT. Results prove that asymmetrical thermoelectric module shows to have almost twofold the thermoelectric figure of merit as compared to conventional one with a constant square cross-section. Thermal analysis of the device via analytical, as well as numerical modeling unveils an increment in the temperature gradient and Seebeck voltage across the device with asymmetrical thermoelectric legs. Such result confirms that the thermoelectric enhancement is due to the harnessing of Thompson effect which is normally neglected in rectangular legs devices. Additionally, the impact of parasitic electrical contact and wiring resistances on the thermoelectric module performance is shown. In this sense, a significant decrement on ZT due to parasitic effects is observed. Thereby, the general results of the present chapter experimentally prove that geometrical configuration of the device legs can improve significantly the thermoelectric performance of the device opening a new route to the development of enhanced performance thermoelectric modules via device engineering.
