Extracting Thermoelectric Properties from Hierarchically Designed Thinner Peltier Sheets

Peltier devices have attracted much attention for their capability of directly coolling down human bodies due to the recent deadly heatwaves. To enlarge the cooling area and lower the weight, we have developed thinner Peltier sheets [ref. 1-3] using sticky thermoelectric (TE) materials [ref. 4,5] based on a hierarchical multi-component strategy; turning element composition of TE particles for high Seebeck coefficient, S, at atomic scale [ref. 6], controlling the surface of TE particles for small electric resistivity, ρ, at nano scale [ref. 6], minimizing thermal conductivity, κ, and absorbing mechanical bending stress by hybridizing organic solvent with the TE particles [ref. 5] and adopting ultra-thin high performance foam sheets at micro-scale [ref. 2], and finally patterning the sticky TE materials and electrodes at macro-scale [ref. 3]. As a design to mass produce thinner Peltier sheets via a roll-to-roll process without using electrically conductive adhesives, the sticky TE materials are deformable to be encapsulated within electrodes and foam sheets. Because of this, however, we could not directly characterize the sticky TE materials based on the analytic tradition in TEs to obtain the figure of merit, ZT = α²T/ρκ, where T is temperature [ref. 6]. Inspired by the previous work to analyze a complex system [ref. 7] based on a methodology adapting from coordination chemistry dealing with metal complexes known by Nobel prize in Chemistry 1913 [ref. 8], we extracted these TE properties from a series of thinner Peltier sheets changing one parameter. In this presentation, we explain the working hypothesis to extract these TE parameters, compare the extracted results with the TE parameters of original TE particles, and discuss the further possibility of the hierarchically designed materials.



[ref. 1] Satoh et al. MRS Adv 2023;8:446-450.
[ref. 2] Satoh et al. MRS Adv 2023;8:781-786.
[ref. 3] Satoh et al. MRS Adv 2024;https://doi.org/10.1557/s43580-024-00937-7
[ref. 4] Satoh et al. Sci Technol Adv Mater 2018;19:517-25.
[ref. 5] Satoh et al. MRS Adv 2020;5:481-487.
[ref. 6] Satoh et al. Soft Sci 2022;2:15.
[ref. 7] Satoh et al. Phys Chem Chem Phys 2012;14:16014-16022.
[ref. 8] Satoh et al. Nat Nanotechnol 2008;3:106-111.