Abstract
High-performance electrodes can be fabricated using environmentally friendly dry processes instead of wet processes. A key material in dry processing is polytetrafluoroethylene (PTFE), which fibrillates under shear stress and forms a robust fibrous network essential for electrode integrity. However, the precise control of PTFE fibrillation is challenging owing to the complex transfer of shear forces from macroscale equipment to microscale particle dynamics. To address this, we present a multiscale optimization framework integrating finite element method simulations, Gaussian process regression, and Bayesian optimization to engineer PTFE fibrillation. Our model identifies the optimal particle size and particle-loaded pressure. It demonstrates that a 10 + 5 µm bimodal system with 14 MPa of particle-loaded pressure yields the most effective fibrillation. Electrodes are inversely designed using 10 + 5 µm particles, and enhanced electrochemical properties are experimentally validated. The proposed optimized dry electrode fabrication bridges microscale particle dynamics with large-scale processing.
Similar content being viewed by others
Data availability
The data that support the findings of this study are available from the corresponding authors upon reasonable request.
Code availability
Codes used to generate the simulation result in this study are available in the Supplementary Code file.
References
Chen, X., Shen, W., Vo, T. T., Cao, Z. & Kapoor, A. An overview of lithium-ion batteries for electric vehicles. 2012 10th Int. Power Energy Conf. (IPEC) 230–235 https://doi.org/10.1109/asscc.2012.6523269. (IPEC, 2012).
Li, J. et al. Toward low-cost, high-energy density, and high-power density lithium-ion batteries. JOM 69, 1484–1496 (2017).
Chouchane, M., Yao, W., Cronk, A., Zhang, M. & Meng, Y. S. Improved rate capability for dry thick electrodes through finite elements method and machine learning coupling. ACS Energy Lett. 9, 1480–1486 (2024).
Jeon, D. H. Wettability in electrodes and its impact on the performance of lithium-ion batteries. Energy Storage Mater. 18, 139–147 (2019).
Kim, S. et al. Scalable dry process for fabricating a Na superionic conductor-type solid electrolyte sheet. ACS Appl. Mater. Interfaces 16, 10307–10315 (2024).
Wang, J. et al. High-area-capacity cathode by ultralong carbon nanotubes for secondary binder-assisted dry coating technology. ACS Appl. Mater. Interfaces 16, 26209–26216 (2024).
Lee, J. et al. Anode interface-stabilizing dry process employing a binary binder system for ultra-thick and durable battery electrode fabrication. Chem. Eng. J. 503, 158271 (2025).
Kim, J. et al. 10 mAh cm−2 cathode by roll‐to‐roll process for low cost and high energy density Li‐ion batteries. Adv. Energy Mater. 14, 2303455 (2024).
Han, S. et al. Mitigating PTFE decomposition in ultra-thick dry-processed anodes for high energy density lithium-ion batteries. J. Energy Storage 96, 112693 (2024).
Kim, N.-Y. et al. Material challenges facing scalable dry-processable battery electrodes. ACS Energy Lett. 9, 5688–5703 (2024).
Kim, H. et al. Ozone-treated carbon nanotube as a conductive agent for dry-processed lithium-ion battery cathode. ACS Energy Lett. 8, 3460–3466 (2023).
Horst, M. et al. Effect of active material morphology on PTFE-fibrillation, powder characteristics and electrode properties in dry electrode coating processes. Powder Technol. 451, 120451 (2025).
Zhang, A. et al. Fibrosis mechanism, crystallization behavior and mechanical properties of in-situ fibrillary PTFE reinforced PP composites. Mater. Des. 211, 110157 (2021).
Li, Y. et al. Progress in solvent-free dry-film technology for batteries and supercapacitors. Mater. Today 55, 92–109 (2022).
Lee, D. et al. Shear force effect of the dry process on cathode contact coverage in all-solid-state batteries. Nat. Commun. 15, 4763 (2024).
Oh, H. et al. Development of a feasible and scalable manufacturing method for PTFE-based solvent-free lithium-ion battery electrodes. Chem. Eng. J. 491, 151957 (2024).
Matthews, G. A. B., Wheeler, S., Ramírez-González, J. & Grant, P. S. Solvent-free NMC electrodes for Li-ion batteries: unravelling the microstructure and formation of the PTFE nano-fibril network. Front. Energy Res. 11, 1336344 (2024).
Yonaga, A. et al. Effects of dry powder mixing on electrochemical performance of lithium-ion battery electrode using solvent-free dry forming process. J. Power Sour. 581, 233466 (2023).
Tao, R. et al. Unraveling the impact of the degree of dry mixing on dry-processed lithium-ion battery electrodes. J. Power Sour. 580, 233379 (2023).
Patil, P. D., Feng, J. J. & Hatzikiriakos, S. G. Constitutive modeling and flow simulation of polytetrafluoroethylene (PTFE) paste extrusion. J. Non-Newton. Fluid Mech. 139, 44–53 (2006).
Kang, J. et al. Tough-interface-enabled stretchable electronics using non-stretchable polymer semiconductors and conductors. Nat. Nanotechnol. 17, 1265–1271 (2022).
Khan, A. & Zhang, H. Finite deformation of a polymer: experiments and modeling. Int. J. Plast. 17, 1167–1188 (2001).
Bergström, J. S. & Hilbert, L. B. A constitutive model for predicting the large deformation thermomechanical behavior of fluoropolymers. Mech. Mater. 37, 899–913 (2005).
Schulz, E., Speekenbrink, M. & Krause, A. A tutorial on Gaussian process regression: modelling, exploring, and exploiting functions. J. Math. Psychol. 85, 1–16 (2018).
Zhang, J. et al. Dual-objectives optimization of lithium metal battery electrolytes via machine learning. Mater. Today Energy 101909 https://doi.org/10.1016/j.mtener.2025.101909 (2025).
Frazier, P. I. A Tutorial on Bayesian Optimization. Preprint at https://doi.org/10.48550/arxiv.1807.02811 (2018).
Arruda, E. M. & Boyce, M. C. A three-dimensional constitutive model for the large stretch behavior of rubber elastic materials. J. Mech. Phys. Solids 41, 389–412 (1993).
Lan, T. et al. A physically-based constitutive model for amorphous glassy polymers in large deformations. Eur. J. Mech. - ASolids 104, 105015 (2024).
Hong, S. B., Kim, J., Gu, N. S. & Yu, W.-R. Constitutive modelling of carbon fiber-reinforced shape memory polymer composites. J. Phys. Conf. Ser. 1063, 012028 (2018).
Kanarik, K. J. et al. Human–machine collaboration for improving semiconductor process development. Nature 616, 707–711 (2023).
Luo, C., Pei, J., Zhuo, W., Niu, Y. & Li, G. Phase transition behavior and deformation mechanism of polytetrafluoroethylene under stretching. RSC Adv. 11, 39813–39820 (2021).
Zhang, Y., Jar, P.-Y. B., Xue, S. & Li, L. Quantification of strain-induced damage in semi-crystalline polymers: a review. J. Mater. Sci. 54, 62–82 (2019).
Fujitani, K., Utsumi, Y., Yamaguchi, A., Sumida, H. & Suzuki, S. Preferential side chain scission of polytetrafluoroethylene by bending stress. Appl. Surf. Sci. 637, 157891 (2023).
Park, S. K., Kim, K. D. & Kim, H. T. Preparation of silica nanoparticles: determination of the optimal synthesis conditions for small and uniform particles. Colloids Surf. A: Physicochem. Eng. Asp. 197, 7–17 (2002).
Haarmann, M., Grießl, D. & Kwade, A. Continuous processing of cathode slurry by extrusion for lithium‐ion batteries. Energy Technol. 9, 2100250 (2021).
Lavrov, A. Numerical modeling of steady-state flow of a non-Newtonian power-law fluid in a rough-walled fracture. Comput. Geotech. 50, 101–109 (2013).
Hwang, J. H., Yoo, H., Oh, S. & Kim, H. Relationship between particle shape and fast-charging capability of a dry-processed graphite electrode in lithium-ion batteries. Electrochem. Commun. 165, 107761 (2024).
Kim, Y. et al. Investigation of mass loading of cathode materials for high energy lithium-ion batteries. Electrochem. Commun. 147, 107437 (2023).
Shi, Y. et al. Tortuosity modulation toward high‐energy and high‐power lithium metal batteries. Adv. Energy Mater. 11, 2003663 (2021).
Kwon, K. et al. Low‐resistance LiFePO4 thick film electrode processed with dry electrode technology for high‐energy‐density lithium‐ion batteries. Small Sci. 4, 2300302 (2024).
Bi, Z. & Mueller, D. W. Friction predication on pin-to-plate interface of PTFE material and steel. Friction 7, 268–281 (2019).
Acknowledgements
This research was supported by the National R&D Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (No. RS-2024-00408156). This research was also supported by the National R&D Program through the NRF funded by the Ministry of Science and ICT (RS-2024-00407282).
Author information
Authors and Affiliations
Contributions
J.H.K. and W.J. contributed equally to this work. J.H.K.: Writing—original draft, Conceptualization, Methodology, Software, Investigation, Formal analysis, Visualization. W.J.: Writing—original draft, Methodology, Investigation, Validation, Formal analysis. M.S.K.: Software, Formal analysis. H.W.K.: Visualization. D.W.J.: Formal analysis, Visualization. H.U.L.: Visualization. J.H.H.: Visualization. S.H.: Investigation, Validation. M.K.: Investigation, Validation. S.Y.: Investigation, Validation. D.L.: Supervision. P.J.K.: Supervision. T.S.: Supervision. M.Y.: Supervision. L.S.: Supervision. J.C.: Writing—review & editing, Supervision, Funding acquisition, Project administration. S.B.C.: Writing—review & editing, Supervision, Funding acquisition, Project administration.
Corresponding authors
Ethics declarations
Competing interests
The authors declare no competing interests.
Peer review
Peer review information
Communications Materials thanks Qiang Zhang, Victor A. Beck and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. A peer review file is available.
Additional information
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
About this article
Cite this article
Kang, J.H., Jeong, W., Kang, M.S. et al. Multiscale insights enable rational design of solvent-free dry electrode processing for advanced battery electrode fabrication. Commun Mater (2025). https://doi.org/10.1038/s43246-025-01046-0
Received:
Accepted:
Published:
DOI: https://doi.org/10.1038/s43246-025-01046-0
