Integrating material engineering with module design optimization: A new design concept for thermoelectric generator

A new thermoelectric (TE) module design concept and a related TE composite are presented in this work to minimize or even to eliminate heat loss between the hot and the cold junctions, to lower the effective thermal conductivity of the composite, and thus, to enhance the module performance. An analytical thermoelectric model is formulated based on the TE energy transport equation, the heat balance equation at the junctions, and Ohm's law to determine TE module performance and the difference in performance between the new and the traditional module designs. Different TE composites and parameters that affect the performance of the TE module were examined using the TE model. Comparing to the traditional module design, the new TE module design can enhance the power generation by 8-30% and the efficiency by 40-60%. When the transport properties of the TE composite is optimized to have higher electrical conductivity than its thermal conductivity, the effective figure of merit (Z) of the composite becomes higher than the Z of the hosting TE materials of the composite such that the module performance can surpass the upper bound set forth by the figure of merit of the hosting TE materials in the traditional module design.