Quantitative Relationship between Structural Parameters and Output Power Density in Lattice Thermoelectric Legs

doi:10.15541/jim20260037

Abstract

Abstract: Unlike traditional bulk thermoelectric legs, recent studies show lattice-structured ones are a cost-effective strategy for boosting output power density. However, the intrinsic relationship between their structural parameters and thermoelectric performance lacks systematic analysis. This work investigated the relationship between two key structural parameters (strut diameter and lattice period) of lattice thermoelectric legs and the maximum output power density under different boundary conditions via an approximate calculation method for the heat transfer and electrical conduction of the extensively distributed diagonal struts in lattice structures. Then, the relationship between strut elements and the integral structure, as well as the influence of nodes, was taken into account during the transition from individual strut elements to the overall lattice structure. Finally, the correlation between structural parameters and output power density was derived by integrating the one-dimensional energy balance theory. Results show that under convective heat transfer boundary, lattice-structured thermoelectric legs have significant advantages in temperature difference and output power density over bulk structures due to their high thermal resistance. When the heat transfer coefficient is 200 W·m^-2·K^-1 (a common value in practical applications), adjusting the structural parameters makes the temperature difference ratio 2.4 times that of the bulk structure and the output power density 3.8 times. Our work provides theoretical guidance for the development of cost-effective thermoelectric devices.

Key words: thermoelectric generator, lattice thermoelectric leg, theoretical model, output power density

CLC Number:

TQ174

ZHOU Jie, CHEN Gang, LI Guodong. Quantitative Relationship between Structural Parameters and Output Power Density in Lattice Thermoelectric Legs[J]. Journal of Inorganic Materials, DOI: 10.15541/jim20260037.

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