Multifunctional Polyfluoride Ionogel‐Encapsulated Lithium Anodes for Durable and Safe Pouch Cells under Harsh Conditions

Multifunctional Polyfluoride Ionogel‐Encapsulated Lithium Anodes for Durable and Safe Pouch Cells under Harsh Conditions

Advanced Functional Materials

10.1002/adfm.202507310

https://doi.org/10.1002/adfm.202507310

Ting Li, Anjun Hu, Yuanjian Li, Borui Yang, Kun Li, Kai Chen, Jingyun Jiang, Fei Li, Zhi Wei Seh, Jian Wang, Jianping Long

23 May 2025

Li, T., Hu, A., Li, Y., Yang, B., Li, K., Chen, K., Jiang, J., Li, F., Seh, Z. W., Wang, J., Long, J. (2025). Multifunctional Polyfluoride Ionogel‐Encapsulated Lithium Anodes for Durable and Safe Pouch Cells under Harsh Conditions. Advanced Functional Materials, 35(45). Portico. https://doi.org/10.1002/adfm.202507310

Lithium metal is environmentally sensitive and highly reactive, especially when coupled with flammable organic electrolytes, which pose critical safety challenges for lithium metal batteries under harsh operational conditions. This study tackles this challenge by constructing an integrated strategy for encapsulating lithium metal with a multifunctional polyfluoride ionogel (PFIGE) through in situ thermal polymerization. Based on the cross-linking network design of hexafluorobutyl methacrylate monomer and 1-butyl-3-lithium bis(trifluoromethylsulfonyl)imide ionic liquid plasticizer, C−F group and TFSI− anion cooperate to confer excellent water/oxygen barrier properties of the PFIGE. Meanwhile, the fluorinated skeleton optimizes the Li+ flux by regulating anion migration, thereby promoting the formation of stable inorganic-rich interphases and achieving homogeneous lithium deposition. Additionally, the C−F group forms ion−dipole interactions with imidazole cations to achieve dynamic self-healing capabilities, while the condensed-phase physical barrier and gas-phase radical scavenging effect of the pyrolyzed PFIGE synergistically contribute to the battery safety. As a proof-of-concept, PFIGE-integrated Li||LiNi0.5Co0.2Mn0.3O2 cells demonstrate extended cycling stability at high voltage (4.6 V) and high temperature (80 °C), and a 0.4 Ah-level pouch cell exhibits exceptional resistance to thermal runaway under mechanical/electrical/thermal abuse conditions. This design philosophy presents a paradigm-shifting electrolyte system that significantly enhances the cycle life and safety of lithium metal batteries.

Publisher Copyright

This research / project is supported by the Singapore National Research Foundation - NRF Investigatorship NRF-NRFI09-0002
Grant Reference no. : NRF-NRFI09-0002

This research / project is supported by the the Agency for Science, Technology and Research - Manufacturing, Trade, and Connectivity Programmatic Fund M23L9b0052
Grant Reference no. : M23L9b0052

This is the peer reviewed version of the following article: Li, T., Hu, A., Li, Y., Yang, B., Li, K., Chen, K., Jiang, J., Li, F., Seh, Z. W., Wang, J., & Long, J. (2025). Multifunctional Polyfluoride Ionogel‐Encapsulated Lithium Anodes for Durable and Safe Pouch Cells under Harsh Conditions. Advanced Functional Materials, 35(45). Portico. https://doi.org/10.1002/adfm.202507310 , which has been published in final form at https://doi.org/10.1002/adfm.202507310. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited.

https://oar.a-star.edu.sg/communities-collections/articles/23496

1616-301X
1616-3028

Institute of Materials Research and Engineering