Seeking high energy conversion efficiency in a fully temperature-dependent thermoelectric medium

The material parameters associated with a thermoelectric medium show strong temperature dependence when the medium is subjected to a wide range of temperatures. This motivates the need to investigate the thermal-electric conversion efficiency of a temperature-dependent medium. In this paper, we develop the temperature field and electric potential associated with a one-dimensional thermoelectric medium with particular attention paid to the influence of various material parameters on the thermal-electric conversion efficiency. We use both theoretical and numerical methods and illustrate our results using several detailed numerical examples. Our numerical results show that the Thomson heat induced by a variable Seebeck coefficient is responsible for more than 20% of total energy leading to a 13% effect on the thermal-electric conversion efficiency. This remarkable result indicates that the thermalelectric conversion efficiency can be effectively optimized by controlling the heat exchange between the thermoelectric medium and its surroundings. In addition, our results indicate that when dealing with a large temperature range, the maximum thermal-electric conversion efficiency should not be taken as a function solely of an average thermoelectric figure of merit since it can vary considerably with different material parameters. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

This paper investigates the temperature field and electric potential of a thermoelectric medium and analyzes the impact of different material parameters on the thermal-electric conversion efficiency. Numerical results show that optimizing the heat exchange can effectively enhance the thermal-electric conversion efficiency.