Novel, high efficiency segmented thermoelectric unicouples for space and terrestrial applications

T. Caillat, J. Sakamoto, J. Snyder, J.-P. Fleurial

Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, MS 277/207 Pasadena, California , USA

New, high efficiency segmented unicouples are currently being developed at the Jet Propulsion Laboratory (JPL). These unicouples incorporate a combination of state-of-the-art thermoelectric materials based on Bi2Te3 and novel, high ZT p-type p-type CeFe4Sb12-based alloys and n-type CoSb3-based alloys initially developed at JPL. The maximum predicted thermal to electrical efficiency is about 15% for a hot-side temperature of 975K and a cold-side temperature of about 300K. The different challenges for the development of this unicouples are reviewed and described. Recent developments are also presented and discussed. In particular, some thermal and electrical testing results and preliminary degradation mechanism studies are reported. Future challenges to fully and further develop this technology as well potential space and terrestrial applications are discussed. The potential of thermoelectric systems based on this advanced technology is compared to state-of-the-art.