High-Power-Density Skutterudite-Based Thermoelectric Modules with Ultralow Contact Resistivity Using Fe–Ni Metallization Layers

Abstract

Most reported thermoelectric modules suffer from considerable power loss due to high electrical and thermal resistivity arising at the interface between thermoelectric legs and metallic contacts. Despite increasing complaints on this critical problem, it has been scarcely tackled. Here we report the metallization layer of Fe−Ni alloy seamlessly securing skutterudite materials and metallic electrodes, allowing for a minimal loss of energy transferred from the former. It is applied to an 8couple thermoelectric module that consists of n-type (Mm,Sm) y Co 4 Sb 12 (ZT max = 0.9) and p-type DD y Fe 3 CoSb 12 (ZT max = 0.7) skutterudite materials. It performs as a diffusion barrier suppressing chemical reactions to produce a secondary phase at the interface. Consequent high thermal stability of the module results in the lowest reported electrical contact resistivity of 2.2−2.5 μΩ cm 2 and one of the highest thermoelectric power density of 2.1 W cm −2 for a temperature difference of 570 K. Employing a scanning transmission electron microscope equipped with an energy-dispersive X-ray spectroscope detector, we confirmed that it is negligible for atomic diffusion across the interface and resulting formation of a detrimental secondary phase to energy transfer and thermal stability of the thermoelectric module.

Artificial Neural Network and Adaptive Neuro-Fuzzy Interface System Modelling to Predict Thermal Performances of Thermoelectric Generator for Waste Heat Recovery

“…Therefore, considering the computational time and the computational cost, the grid element number of 11,431,310 is selected as the final mesh configuration for the thermoelectric generator system for waste heat recovery to predict its current, power and thermal efficiency numerically. In numerical analysis, the density, specific heat, thermal conductivity and dynamic viscosity of the hot gas are set as 1.19 kg/m 3 [22]. The continuity, momentum and energy equations are expressed with Equations (2) to (5) [23].…”

Fabrication of Skutterudite-Based Tubular Thermoelectric Generator

“…To show the usefulness of the MRW process for the fabrication of tubular TEG, we compared the power density and zT avg of other skutterudite-based modules to this work, as shown in Figure 5 [33,[38][39][40]. Previous research methods employed high-performance TE material to the module, resulting in high zT avg , especially in the case of p-type.…”

Determination of the thermoelectric properties of a skutterudite-based device at practical operating temperatures by impedance spectroscopy

“…Commercial SKD powders (composition DDyFe3CoSb12 for p-type SKD and (Mm,Sm)yCo4Sb12 for n-type SKD, where DD and Mm stand for didymium and mischmetal, respectively) were provided by Treibacher Industrie AG [24,41]. The as-received SKD powders (3 g) were sandwiched between two Ti foils (50 μm thickness, Alfa Aesar, 99.6%) and then coldpressed using a graphite die with a diameter of 12 mm.…”

“…Owing to the increasing demand for waste heat harvesting technologies, significant advances have been made over the past few decades toward the development of highly efficient bismuth telluride [1][2][3], germanium telluride [4,5], lead telluride [6,7], skutterudite (SKD) [8][9][10][11][12], half-Heusler [9,[13][14][15], and oxide [9,14] based materials as well as bismuth telluride [16,17], lead telluride [18,19], SKD [20][21][22][23][24][25], half-Heusler [26][27][28] based thermoelectric devices.…”