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Compliant and stretchable thermoelectric coils for energy harvesting in miniature flexible devices

Nan, Kewang and Kang, Stephen Dongmin and Li, Kan and Yu, Ki Jun and Zhu, Feng and Wang, Juntong and Dunn, Alison C. and Zhou, Chaoqun and Xie, Zhaoqian and Agne, Matthias T. and Wang, Heling and Luan, Haiwen and Zhang, Yihui and Huang, Yonggang and Snyder, G. Jeffrey and Rogers, John A. (2018) Compliant and stretchable thermoelectric coils for energy harvesting in miniature flexible devices. Science Advances, 4 (11). Art. No. eaau5849. ISSN 2375-2548. PMCID PMC6214638.

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With accelerating trends in miniaturization of semiconductor devices, techniques for energy harvesting become increasingly important, especially in wearable technologies and sensors for the internet of things. Although thermoelectric systems have many attractive attributes in this context, maintaining large temperature differences across the device terminals and achieving low–thermal impedance interfaces to the surrounding environment become increasingly difficult to achieve as the characteristic dimensions decrease. Here, we propose and demonstrate an architectural solution to this problem, where thin-film active materials integrate into compliant, open three-dimensional (3D) forms. This approach not only enables efficient thermal impedance matching but also multiplies the heat flow through the harvester, thereby increasing the efficiencies for power conversion. Interconnected arrays of 3D thermoelectric coils built using microscale ribbons of monocrystalline silicon as the active material demonstrate these concepts. Quantitative measurements and simulations establish the basic operating principles and the key design features. The results suggest a scalable strategy for deploying hard thermoelectric thin-film materials in harvesters that can integrate effectively with soft materials systems, including those of the human body.

Item Type:Article
Related URLs:
URLURL TypeDescription Materials CentralArticle
Nan, Kewang0000-0002-2745-0656
Kang, Stephen Dongmin0000-0002-7491-7933
Li, Kan0000-0003-4864-3446
Dunn, Alison C.0000-0002-4841-1293
Zhou, Chaoqun0000-0002-2744-7916
Agne, Matthias T.0000-0001-8270-5730
Wang, Heling0000-0001-7859-5153
Luan, Haiwen0000-0003-0722-1108
Zhang, Yihui0000-0003-0885-2067
Huang, Yonggang0000-0002-0483-8359
Snyder, G. Jeffrey0000-0003-1414-8682
Rogers, John A.0000-0002-3830-5980
Additional Information:© 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution Noncommercial License 4.0 (CC BY-NC). Submitted 26 June 2018; Accepted 2 October 2018; Published 2 November 2018. We thank X. Shan for the help in taking and processing images. Funding: We acknowledge the support from the U.S. Department of Energy, Office of Science, Basic Energy Sciences through the following programs: J.A.R. acknowledges DE-FG02-07ER46471; G.J.S. acknowledges S3TEC, an Energy Frontier Research Center (DE-SC0001299). Y.H. acknowledges the support from the NSF (1400169, 1534120, and 1635443). Z.X. acknowledges the support from the National Natural Science Foundation of China (11402134). K.J.Y. acknowledges the support from the National Research Foundation of Korea (NRF-2017M1A2A2048880 and NRF-2018M3A7B4071109) and the Yonsei University Future-leading Research Initiative (RMS2 2018-22-0028). The experimental work was carried out, in part, in the Frederick Seitz Materials Research Laboratory, Central Research Facilities, University of Illinois. Author contributions: K.N. developed the fabrication process and produced the device. S.D.K. oversaw the thermal and thermoelectric analyses, measured the thermoelectric properties, and modeled the thermal and power characteristics. K.L. designed the 3D coil structure, optimized the geometric parameters based on coupled thermal and mechanical FEA, and drew the masks. A.C.D. did the mechanical characterization. K.J.Y., J.W., and C.Z. assisted the fabrication process. F.Z., Z.X., and H.W. assisted the FEA and optimization. M.T.A. assisted thermoelectric characterization. H.L. helped to design the mask. S.D.K., K.N., and K.L. wrote the manuscript. Y.Z., Y.H., G.J.S., and J.A.R. supervised the project. All authors reviewed or edited the manuscript. The authors declare that they have no competing interests. Data and materials availability: All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. Additional data related to this paper may be requested from the authors.
Funding AgencyGrant Number
Department of Energy (DOE)DE-FG02-07ER46471
Department of Energy (DOE)DE-SC0001299
National Natural Science Foundation of China11402134
National Research Foundation of Korea2017M1A2A2048880
National Research Foundation of Korea2018M3A7B4071109
Yonsei UniversityRMS2 2018-22-0028
Issue or Number:11
PubMed Central ID:PMC6214638
Record Number:CaltechAUTHORS:20181106-125510643
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:90673
Deposited By: Tony Diaz
Deposited On:06 Nov 2018 21:55
Last Modified:03 Oct 2019 20:27

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