Flexible thermoelectric generator with liquid metal interconnects and low thermal conductivity silicone filler
Source abstract
Abstract
Abstract Harvesting body heat using thermoelectricity provides a promising path to realizing self-powered, wearable electronics that can achieve continuous, long-term, uninterrupted health monitoring. This paper reports a flexible thermoelectric generator (TEG) that provides efficient conversion of body heat to electrical energy. The device relies on a low thermal conductivity aerogel–silicone composite that secures and thermally isolates the individual semiconductor elements that are connected in series using stretchable eutectic gallium-indium (EGaIn) liquid metal interconnects. The composite consists of aerogel particulates mixed into polydimethylsiloxane (PDMS) providing as much as 50% reduction in the thermal conductivity of the silicone elastomer. Worn on the wrist, the flexible TEGs present output power density figures approaching 35 μWcm−2 at an air velocity of 1.2 ms−1, equivalent to walking speed. The results suggest that these flexible TEGs can serve as the main energy source for low-power wearable electronics.
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Research context
OpenAlex topics: Advanced Sensor and Energy Harvesting Materials · Advanced Thermoelectric Materials and Devices · Thermal Radiation and Cooling Technologies
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (60)
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1. Siddique, A. R. M., Mahmud, S. & Heyst, B. V. A review of the state of the science on wearable thermoelectric power generators (tegs) and their existing challenges. Renew. Sust. Energ. Rev. 73, 730–744 (2017).10.1016/j.rser.2017.01.177 ↗
2. Mateu, L. & Moll, F. Review of energy harvesting techniques and applications for microelectronics. https://doi.org/10.1117/12.613046, (2005).10.1117/12.613046, ↗
3. Dagdeviren, C., Li, Z. & Wang, Z. L. Energy harvesting from the animal/human body for self-powered electronics. Annu. Rev. Biomed. Eng. 19, 85–108 (2017).10.1146/annurev-bioeng-071516-044517 ↗
4. Jo, S., Kim, M., Kim, M. & Kim, Y. Flexible thermoelectric generator for human body heat energy harvesting. Electron. Lett. 48, 1015–1017 (2012).10.1049/el.2012.1566 ↗
5. Huu, T. N., Van, T. N. & Takahito, O. Flexible thermoelectric power generator with y-type structure using electrochemical deposition process. Appl. Energy 210, 467–476 (2018).10.1016/j.apenergy.2017.05.005 ↗
6. Morata, A. et al. Large-area and adaptable electrospun silicon-based thermoelectric nanomaterials with high energy conversion efficiencies. Nat. Commun. 9, 4759 (2018).10.1038/s41467-018-07208-8 ↗
7. Wang, Y., Shi, Y., Mei, D. & Chen, Z. Wearable thermoelectric generator to harvest body heat for powering a miniaturized accelerometer. Appl. Energy 215, 690–698 (2018).10.1016/j.apenergy.2018.02.062 ↗
8. Kim, C. S. et al. Structural design of a flexible thermoelectric power generator for wearable applications. Appl. Energy 214, 131–138 (2018).10.1016/j.apenergy.2018.01.074 ↗
9. Eom, Y., Wijethunge, D., Park, H., Park, S. H. & Kim, W. Flexible thermoelectric power generation system based on rigid inorganic bulk materials. Appl. Energy 206, 649–656 (2017).10.1016/j.apenergy.2017.08.231 ↗
10. Ito, M. et al. From materials to device design of a thermoelectric fabric for wearable energy harvesters. J. Mater. Chem. A 5, 12068–12072 (2017).10.1039/C7TA00304H ↗
11. Oh, J. Y. et al. Chemically exfoliated transition metal dichalcogenide nanosheet-based wearable thermoelectric generators. Energy Environ. Sci. 9, 1696–1705 (2016).10.1039/C5EE03813H ↗
12. Liu, H., Wang, Y., Mei, D., Shi, Y. & Chen, Z. Wearable Sensors and Robots, 55–66 (Springer, 2017).10.1007/978-981-10-2404-7_5 ↗
13. Toshima, N. Recent progress of organic and hybrid thermoelectric materials. Synth. Met. 225, 3–21 (2017).10.1016/j.synthmet.2016.12.017 ↗
14. Glatz, W., Muntwyler, S. & Hierold, C. Optimization and fabrication of thick flexible polymer based micro thermoelectric generator. Sens. Actuator A Phys. 132, 337–345 (2006).10.1016/j.sna.2006.04.024 ↗
15. Koukharenko, E. et al. Towards a nanostructured thermoelectric generator using ion-track lithography. J. Micromech. Microeng. 18, 104015 (2008).10.1088/0960-1317/18/10/104015 ↗
16. Cao, Z., Koukharenko, E., Tudor, M., Torah, R. & Beeby, S. Screen printed flexible bi2te3- sb2te3 based thermoelectric generator. J. Phys. 476, 012031 (2013).
17. Chen, G., Xu, W. & Zhu, D. Recent advances in organic polymer thermoelectric composites. J. Mater. Chem. C. 5, 4350–4360 (2017).10.1039/C6TC05488A ↗
18. Kim, S. J., We, J. H. & Cho, B. J. A wearable thermoelectric generator fabricated on a glass fabric. Energy Environ. Sci. 7, 1959–1965 (2014).10.1039/c4ee00242c ↗
19. Siddique, A. R. M., Rabari, R., Mahmud, S. & Van Heyst, B. Thermal energy harvesting from the human body using flexible thermoelectric generator (fteg) fabricated by a dispenser printing technique. Energy J. 115, 1081–1091 (2016).10.1016/j.energy.2016.09.087 ↗
20. Wang, L. et al. Solution-printable fullerene/tis 2 organic/inorganic hybrids for high- performance flexible n-type thermoelectrics. Energy Environ. Sci. 11, 1307–1317 (2018).10.1039/C7EE03617E ↗
21. Allison, L. K. & Andrew, T. L. A wearable all-fabric thermoelectric generator. Adv. Mater. Technol. 4, 1800615, https://doi.org/10.1002/admt.201800615 (2019).10.1002/admt.201800615 ↗
22. Itoigawa, K., Ueno, H., Shiozaki, M., Toriyama, T. & Sugiyama, S. Fabrication of flexible thermopile generator. J. Micromech. Microeng. 15, S233 (2005).10.1088/0960-1317/15/9/S10 ↗
23. Weber, J. et al. Coin-size coiled-up polymer foil thermoelectric power generator for wearable electronics. Sens. Actuator A Phys. 132, 325–330 (2006).10.1016/j.sna.2006.04.054 ↗
24. Suarez, F. et al. Flexible thermoelectric generator using bulk legs and liquid metal interconnects for wearable electronics. Appl. Energy 202, 736–745 (2017).10.1016/j.apenergy.2017.05.181 ↗
25. OzturkM. et al. Flexible thermoelectric generator and methods of manufacturing. US Patent 10,431,726. (2019)
26. Dickey, M. D. Emerging applications of liquid metals featuring surface oxides. ACS Appl. Mater. Interfaces 6, 18369–18379 (2014).10.1021/am5043017 ↗
27. Dickey, M. D. Stretchable and soft electronics using liquid metals. Adv. Mater. 29, 1606425 (2017).10.1002/adma.201606425 ↗
28. Ladd, C., So, J.-H., Muth, J. & Dickey, M. D. 3d printing of free-standing liquid metal microstructures. Adv. Mater. 25, 5081–5085 (2013).10.1002/adma.201301400 ↗
29. Zrnic, D. & Swatik, D. On the resistivity and surface tension of the eutectic alloy of gallium and indium. J. Less Common Met. 18, 67–68 (1969).10.1016/0022-5088(69)90121-0 ↗
30. Stephan, K. & Laesecke, A. The thermal conductivity of fluid air. J. Phys. Chem. Ref. Data. 14, 227 (1985).10.1063/1.555749 ↗
31. Ubong Eduok*, J. S., Omar Faye. Recent developments and applications of protective silicone coatings: a review of PDMS functional materials. Prog. Org. Coat. 111, 124–163, https://doi.org/10.1016/j.porgcoat.2017.05.012 (2017).10.1016/j.porgcoat.2017.05.012 ↗
32. Wei, G., Liu, Y., Zhang, X., Yu, F. & Du, X. Thermal conductivities study on silica aerogel and its composite insulation materials. Int. J. Heat. Mass Transf. 54, 2355–2366 (2011).10.1016/j.ijheatmasstransfer.2011.02.026 ↗
33. Notario, B. et al. Experimental validation of the Knudsen effect in nanocellular polymeric foams. Polym. J. 56, 57–67 (2015).10.1016/j.polymer.2014.10.006 ↗
34. Woignier, T. et al. Mechanical properties and brittle behavior of silica aerogels. Gels 1, 256–275 (2015).10.3390/gels1020256 ↗
35. Suarez, F., Nozariasbmarz, A., Vashaee, D. & Öztürk, M. C. Designing thermoelectric gener- ators for self-powered wearable electronics. Energy Environ. Sci. 9, 2099–2113 (2016).10.1039/C6EE00456C ↗
36. Yu, S. & Kaviany, M. Electrical, thermal, and species transport properties of liquid eutectic Ga-In and Ga-In-Sn from first principles. J. Chem. Phys. 140, 064303 (2014).10.1063/1.4865105 ↗
37. Liu, M., Sun, J., Sun, Y., Bock, C. & Chen, Q. Thickness-dependent mechanical properties of polydimethylsiloxane membranes. J. Micromech. Microeng. 19, 035028 (2009).10.1088/0960-1317/19/3/035028 ↗
38. Bartlett, M. D. et al. High thermal conductivity in soft elastomers with elongated liquid metal inclusions. Proc. Natl Acad. Sci. USA 114, 2143–2148, https://doi.org/10.1073/pnas.1616377114 (2017).10.1073/pnas.1616377114 ↗
39. Jeong, S. H. et al. Stretchable thermoelectric generators metallized with liquid alloy. ACS Appl. Mater. Interfaces 9, 15791–15797 (2017).10.1021/acsami.7b04752 ↗
40. Sargolzaeiaval, Y. et al. High thermal conductivity silicone elastomer doped with graphene nanoplatelets and eutectic gain liquid metal alloy. ECS J. Solid State Sci. Technol. 8, P357–P362 (2019).10.1149/2.0271906jss ↗
41. Gent, A. N. & Park, B. Failure processes in elastomers at or near a rigid spherical inclusion. J. Mater. Sci. 19, 1947–1956 (1984).10.1007/BF00550265 ↗
42. Sargolzaeiaval, Y. et al. Flexible thermoelectric generators for body heat harvesting–enhanced device performance using high thermal conductivity elastomer encapsulation on liquid metal interconnects. Appl. Energy 262, 114370 (2020).10.1016/j.apenergy.2019.114370 ↗
43. Suarez, F., Nozariasbmarz, A., Vashaee, D. & Öztürk, M. C. Designing thermoelectric generators for self-powered wearable electronics. Energy Environ. Sci. 9, 2099–2113 (2016).10.1039/C6EE00456C ↗
44. Kanitakis, J. Anatomy, histology and immunohistochemistry of normal human skin. Eur J. Dermatol. 12, 390–401 (2002).
45. Thielen, M., Kara, G., Unkovic, I., Majoe, D. & Hierold, C. Thermal harvesting potential of the human body. J. Electron Mater. 47, 3307–3313 (2018).10.1007/s11664-018-6095-y ↗
46. Sevilla, G. A. T., Inayat, S. B., Rojas, J. P., Hussain, A. M. & Hussain, M. M. Flexible and semi-transparent thermoelectric energy harvesters from low cost bulk silicon (100). Small 9, 3916–3921 (2013).10.1002/smll.201301025 ↗
47. Lee, J. A. et al. Woven-yarn thermoelectric textiles. Adv. Mater. 28, 5038–5044 (2016).10.1002/adma.201600709 ↗
48. Glatz, W., Schwyter, E., Durrer, L. & Hierold, C. Bi2Te3-based flexible micro thermoelectric generator with optimized design. J. Microelectromech. Syst. 18, 763–772 (2009).10.1109/JMEMS.2009.2021104 ↗
49. Kim, S. J. et al. High-performance flexible thermoelectric power generator using laser multi- scanning lift-off process. ACS Nano 10, 10851–10857 (2016).10.1021/acsnano.6b05004 ↗
50. Romano, M. R. et al. Safety of silicone oils as intraocular medical device: an in vitro cytotoxicity study. Exp. Eye Res. 194, 108018 (2020).10.1016/j.exer.2020.108018 ↗
51. Goudie, M. J., Pant, J. & Handa, H. Liquid-infused nitric oxide-releasing (LINORel) silicone for decreased fouling, thrombosis, and infection of medical devices. Sci. Rep. 7, 13623 (2017).10.1038/s41598-017-14012-9 ↗
52. Stieghorst, J., Majaura, D., Wevering, H. & Doll, T. Toward 3D printing of medical implants: reduced lateral droplet spreading of silicone rubber under intense IR curing. ACS Appl. Mater. Interfaces 8, 8239–8246 (2016).10.1021/acsami.5b12728 ↗
53. Meran, Z., Besinis, A., De Peralta, T. & Handy, R. D. Antifungal proper- ties and biocompatibility of silver nanoparticle coatings on silicone maxillofacial prostheses in vitro. J. Biomed. Mater. Res. Part B Appl. Biomater. 106, 1038–1051 (2018).10.1002/jbm.b.33917 ↗
54. Xiang, H. et al. UV-curable, 3D printable and biocompatible silicone elastomers. Prog. Org. Coat. 137, 105372 (2019).10.1016/j.porgcoat.2019.105372 ↗
55. Kim, J.-H., Kim, S., So, J.-H., Kim, K. & Koo, H.-J. Cytotoxicity of Gallium-Indium liquid metal in an aqueous environment. ACS Appl. Mater. Interfaces 10, 17448–17454 (2018).10.1021/acsami.8b02320 ↗
56. Lu, Y. et al. Transformable liquid-metal nanomedicine. Nat. Commun. 6, 10066 (2015).10.1038/ncomms10066 ↗
57. Yan, J., Lu, Y., Chen, G., Yang, M. & Gu, Z. Advances in liquid metals for biomedical applications. Chem. Soc. Rev. 47, 2518–2533 (2018).10.1039/C7CS00309A ↗
58. Guo, R. et al. Cu–EGaIn enabled stretchable e-skin for interactive electron- ics and CT assistant localization. Mater. Horiz. 7, 1845–1853 (2020).10.1039/C9MH02066G ↗
59. Guo, R. et al. Semi-liquid-metal-(Ni-EGaIn)-based ultraconformable electronic tattoo. Adv. Mater. Technol. 4, 1900183 (2019).10.1002/admt.201900183 ↗
60. Zadan, M., Malakooti, M. H. & Majidi, C. Soft and stretchable thermoelectric generators enabled by liquid metal elastomer composites. ACS Appl. Mater. Interfaces 12, 17921–17928 (2020).10.1021/acsami.9b19837 ↗