Design of Cascaded Oxide Thermoelectric Generator

抄録

This paper describes the design of two- and three-stage cascaded oxide thermoelectric generators (TEGs) for high-temperature heat recovery using reported data to optimize energy conversion efficiency. We used the general intermetallic compounds Bi₂(Se,Te)₃ and (Bi,Sb)₂Te₃ for the low-temperature stages and oxides of TiO_1.1, La-doped SrTiO₃, Na_xCo₂O₄, and Al-doped ZnO for the higher-temperature stages. A two-stage TEG with TiO_1.1 as the p-type material and La-doped SrTiO₃ as the n-type material was found to have the highest efficiency at heat-source temperatures below 852 K, while the three-stage TEG was slightly more efficient than the two-stage TEG for heat-source temperatures above 852 K. For the three-stage TEG, the optimal boundary temperature of the second and third stages was calculated to be 698 K; at this temperature, the maximum energy conversion efficiency, 13.5%, was obtained at a heat-source temperature of 1223 K. The results showed that the designed two- and three-stage cascaded oxide TEGs have high potential for heat recovery from high-temperature waste.