[en] Thermoelectric modules are energy conversion devices. They are attracting attention as a devices capable of producing electricity by utilizing waste heat. Thermoelectric modules require a high zT, and mechanical stability for reliable operation. In this research, we introduce the groove-type electrode to improve mechanical stability. Each electrode is attached to the thermoelectric element using a silver paste. The tensile and the shear strength of the thermoelectric materials’ electrodes are measured using a universal testing machine. Results show that the groove-type electrode has higher bonding strength than the flat-type electrode. We also confirmed the difference in the performance of the element modeled using flat- and groove-type electrodes for thermo-electric numerical analysis

[en] We introduced a technology for reducing infrared radiation through the active cooling of hot surfaces by using a thermoelectric refrigerator. Certain surfaces were heated by aerodynamic heating, and the heat generation processes are proposed here. We calculated the temperatures and radiations from surfaces, while using thermoelectric refrigerators to cool the surfaces. The results showed that the contrast between the radiations of certain surfaces and the ambient environments can be removed using thermoelectric refrigerators.

[en] To have a very good energy conversion efficiency, thermoelectric (TE) material should exhibit higher figure-of-merit (ZT) for broad range of temperatures. In that direction, n-type PbTe_0.5Se_0.5 material with enhanced and temperature insensitive figure-of-merit was developed through nanostructured approach. A temperature insensitive ZT of 0.7 was observed from 400 K to 600 K. The enhanced and stable ZT over a wide temperature range was ascribed to the presence of various types of nanostructures that facilitated scattering of mid and long wavelength phonons, keeping the thermal conductivity low in addition to scattering low energy charge carriers elevating the Seebeck coefficient (−380 μVK⁻¹ at 600 K). Most thermoelectric n-type materials such as PbQ (Q = Te, Se) materials exhibits very low ZT at room temperature which hampers the overall conversation efficiency. However, the developed material exhibits highest ZT at room temperature among PbQ (Q = Te,Se) materials that enables this material to be used in wearable thermoelectric applications. In this study, newly introduced technique was adopted to calculate TE conversion efficiency, which addresses overestimations of conventional efficiency calculations. The developed material showed power generation efficiency higher than many state-of-the-art TE n-type materials in 300 K–600 K range making it a competitive material for waste heat recovery applications.