Batch Fabrication and Interface Stabilization Accelerate Application of Skutterudite Thermoelectric Module for Power Generation

Abstract

To achieve the commercial application of high‐performance skutterudite (SKD) thermoelectric (TE) devices, breakthroughs in the batch fabrication of TE material and the realization of its stable bonding to the barrier layer are necessary. In this work, the large‐scale SKD bulks with excellent TE performance and decent homogeneity are prepared by melt‐spinning (MS) combined with a hot pressing process. Then, a modified two‐step sintering method is employed to effectively suppress the degree of initial interfacial reaction, resulting in a barrier layer/SKD joint that exhibits low contact resistivity (≈2µΩ·cm2) and high bonding strength (≈30 MPa) with no significant change after aging at 773 K for 30 days. Encouragingly, the joints welded with Mo50Cu50 electrodes also show high stability under the same aging conditions. Finally, the as‐fabricated 8‐pair module shows a highly competitive conversion efficiency of 9% under a temperature difference of 580 K. In addition, during a 360 h aging test with hot‐side temperature of 773 K, the module shows excellent stability. Overall, this work paves the way for batch fabrication of high‐performance SKD using MS and lays a solid foundation for the stable operation of SKD‐based modules.