Review of State of the Art Technologies used to Improve Performance of Thermoelectric Devices

Thermoelectric devices have gained importance in recent years as viable solutions for applications such as spot cooling of electronic components, remote power generation in space stations and satellites etc. These solid state devices have long been known for their reliability rather than their efficiency as they contain no moving parts. Research in recent years has been focused towards developing both thermoelectric structures and materials that have high efficiency characterized by the quantity known as the figure of merit ZT = SσT/κ where S is the Seebeck coefficient, σ the electrical conductivity and κ the thermal conductivity. In general thermoelectric research is twopronged with 1) experiments focused towards finding new materials and structures with enhanced thermoelectric performance and 2) analytical models that predict thermoelectric behavior to enable better design and optimization of materials and structures. In this paper we present a review of the theoretical models that were developed since thermoelectricity was first observed in 1821 by Seebeck and how these models have guided experimental materials search for improved thermoelectric devices. A new quantum model is also presented, which provides opportunities for optimization of nanostructured materials to enhance thermoelectric performance.