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arXiv · 1910.11132

General Efficiency Theory of Thermoelectric Conversion

Byungki Ryu·Jaywan Chung·SuDong Park
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Abstract

In this Letter, we show thermoelectric conversion efficiency is \emph{exactly} determined by \emph{three} independent material parameters $Z_{\rm gen}$, $τ$, and $β$. Each parameter is a figure of merit hence improving $τ$ or $β$ is an additional way to increase the efficiency. The $Z_{\rm gen}$ generalizes the traditional figure of merit \emph{zT}. Two degrees of freedom $τ$ and $β$ reflect the temperature gradients of the material properties and are crucial to evaluate the heat current altered by non-zero Thomson heat and asymmetric Joule heat escape. Physical insights on high $τ$ or $β$ materials explain why the single parameter approaches can be inaccurate for efficiency prediction.

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Byungki Ryu, Jaywan Chung, SuDong Park. 2019-10-23. General Efficiency Theory of Thermoelectric Conversion. https://arxiv.org/abs/1910.11132

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