Modeling and Optimization of Small Thermoelectric Generators for Low-Power Electronics

Compact thermoelectric generators operating with small temperature differences can be used to power autonomous circuitry and low-power electronics. This work presents an analysis of potential design optimizations for such devices, also called μTEGs. The analysis considers the effects of external thermal resistances, fill factor, ZT values, and the choice of insulating filler material on the thermoelectric performance. Many of the trends are strongly related to the ratio of internal to external thermal resistance, which determines the proportion of the total temperature drop realized across the active region of the thermoelectric. The results of this analysis provide a framework for thermal optimization of thermoelectric devices designed for small-scale heat to electricity conversion. Further, external thermal resistances are shown to be a dominant factor in performance for compact devices.