Journal of Electronic Materials

, Volume 44, Issue 6, pp 1834–1845

Unileg Thermoelectric Generator Design for Oxide Thermoelectrics and Generalization of the Unileg Design Using an Idealized Metal

  • Waruna Wijesekara
  • Lasse Rosendahl
  • David R. Brown
  • G. Jeffrey Snyder
Article

DOI: 10.1007/s11664-014-3569-4

Cite this article as:
Wijesekara, W., Rosendahl, L., Brown, D.R. et al. Journal of Elec Materi (2015) 44: 1834. doi:10.1007/s11664-014-3569-4

Abstract

The unileg thermoelectric generator (U-TEG) is an increasingly popular concept in the design of thermoelectric generators (TEGs). In this study, an oxide U-TEG design for high-temperature applications is introduced. For the unicouple TEG design, Ca3Co4O9 and Al-doped ZnO are used as the p- and n-leg thermoelectric materials, respectively. For the U-TEG design, constantan and Ca3Co4O9 are employed as conductor and semiconductor, respectively. The reduced current approach (RCA) technique is used to design the unicouple TEG and U-TEG in order to obtain the optimal area ratio. When both the unicouple TEG and U-TEG were subjected to a heat flux of 20 W/cm2, the volumetric power density was 0.18 W/cm3 and 0.44 W/cm3, respectively. Thermal shorting between the hot and cold sides of the generator through the highly thermally conducting conductor, which is one of the major drawbacks of the U-TEG, is overcome by using the optimal area ratio for conductor and semiconductor given by the RCA. The results are further confirmed by finite-element analysis using COMSOL Multiphysics software. Furthermore, the U-TEG design is generalized by using an idealized metal with zero Seebeck coefficient. Even though the idealized metal has no impact on the power output of the U-TEG and all the power in the system is generated by the semiconductor, the U-TEG design succeeded in producing a higher volumetric power density than the unicouple TEG design.

Keywords

Unileg thermoelectric generator TEG thermoelectric volumetric power density thermal shorting 

Copyright information

© The Minerals, Metals & Materials Society 2014

Authors and Affiliations

  • Waruna Wijesekara
    • 1
  • Lasse Rosendahl
    • 1
  • David R. Brown
    • 2
  • G. Jeffrey Snyder
    • 2
  1. 1.Department of Energy TechnologyAalborg UniversityAalborgDenmark
  2. 2.Materials ScienceCalifornia Institute of TechnologyPasadenaUSA