Development of a high efficient thermoelectric stack for a waste exhaust heat recovery of vehicles

The development of a high efficiency thermoelectric (TE) stack, which is a united system of thermoelectric modules and a heat exchanger, has been made to advance the applications of electrical power generation to vehicles. The thermoelectric materials under investigation are mostly heavily doped CoSb₃ and filled skutterudites RM₄Sb₁₂ (R= Ce, Yb,; M=Co, Fe, Ni, Pt, Pd). In order to maximize the conversion efficiency of the devices operating in the 350-750°C temperature range, the p-, n-legs segmented with the skutterudites and state-of-the-art Bi₂Te₃ have been used to build the devices. We could obtain valuable data showing a validity of installing the thermoelectric stack in vehicles, but a few of problems to be solved in a practical level still remain.