High-Performance Skutterudite/Half-Heusler Cascaded Thermoelectric Module Using the Transient Liquid Phase Sintering Joining Technique

Abstract

Thermoelectric (TE) materials have made rapid advancement in the past decade, paving the pathway toward the design of solid-state waste heat recovery systems. The next requirement in the design process is realization of full-scale multistage TE devices in the medium to high temperature range for enhanced power generation. Here, we report the design and manufacturing of full-scale skutterudite (SKD)/half-Heusler (hH) cascaded TE devices with 49-couple TE legs for each stage. The automated pick-and-place tool is employed for module fabrication providing overall high manufacturing process efficiency and repeatability. Optimized Ti/Ni/Au coating layers are developed for metallization as the diffusion barrier and electrode contact layers. The Cu−Sn transient liquid phase sintering technique is utilized for SKD and hH stages, which provides a high strength bonding and very low contact resistance. A remarkably high output power of 38.3 W with a device power density of 2.8 W•cm −2 at a temperature gradient of 513 °C is achieved. These results provide an avenue for widespread utilization of TE technology in waste heat recovery applications.

Multi-source energy harvesting technology using piezoelectric and thermoelectric materials

“…In past decades, different strategies to overcome the challenges of contact resistance in bulk TE devices have been developed [3,[13][14][15]17]. For instance, a direct bonding technique for hH TE devices was developed, which demonstrated negligible contact resistance and clear interface, thereby achieving good TE performance with thermal stability (Figure 4a) [14].…”

“…An optimized Ti/Ni/Au coating layers were developed for metallization as the diffusion barrier and electrode contact layers, and the Cu-Sn transient liquid phase sintering technique is utilized for SKD and hH stages, which provides a high strength bonding and very low contact resistance (Figure 4b). [13] Figure 4 Metallization techniques of TE devices. (a) Direct bonding technique [14].…”

“…TE power generation technologies may play a crucial role for harnessing the heat generated by high-speed aerial vehicles like jet engines, rockets, and hypersonic crafts. These technologies enhance fuel efficiency, reduce CO 2 emission, and supply vital power for critical flight systems such as control, navigation, and communications [6,[12][13][14][15][16][17][18][19]. Additionally, compact TE generators (TEGs) 2 can tap into flight-generated heat to offer on-the-spot power for sensors and electronics in remote locations, enabling wireless operations.…”

High-Entropy Engineering in Thermoelectric Materials: A Review

“…Thermoelectric generators (TEGs) represent a direct energy conversion between heat and electricity, which shows promise in harvesting green energy from waste heat and provides an alternative to conventional cooling technology [8,9,[13][14][15][16][17][18]. TE conversion efficiency (η) of a TEG primarily depends on the TE material's dimensionless average figure of merit (zT avg ) under a temperature gradient (∆T = T h − T C ; T h and T C are the hot-side and cold-side temperature of a TEG device, respectively) as [19][20][21] follows:…”

Development of Cu2Se/Ag2(S,Se)-Based Monolithic Thermoelectric Generators for Low-Grade Waste Heat Energy Harvesting

“…However, assembly of these devices requires a complicated and energy-intensive process. Aside from the significant amount of research being done to develop new high-performance TE materials to replace Bi 2 Te 3 -based materials, a significant amount of research is also being done to develop new device architectures to improve power generation and energy conversion efficiency − or to simplify and reduce the manufacturing cost for TEG modules …”