Versatile Molecular Engineering of In Situ Cross-Linked Multifunctional Electrolytes for Long-Lifetime and Safe Semisolid Lithium Metal Batteries

Versatile Molecular Engineering of In Situ Cross-Linked Multifunctional Electrolytes for Long-Lifetime and Safe Semisolid Lithium Metal Batteries

ACS Nano

10.1021/acsnano.5c00990

https://doi.org/10.1021/acsnano.5c00990

Kai Chen, Anjun Hu, Guo-Rui Zhu, Yuanjian Li, Jingyun Jiang, Borui Yang, Ting Li, Kun Li, Jingze Chen, Wang Xu, Zhen Wang, Ruize Xu, Wei Yang, Jian Wang, Gang Wu, Jianping Long, Zhi Wei Seh

07 April 2025

Chen, K., Hu, A., Zhu, G.-R., Li, Y., Jiang, J., Yang, B., Li, T., Li, K., Chen, J., Xu, W., Wang, Z., Xu, R., Yang, W., Wang, J., Wu, G., Long, J., & Seh, Z. W. (2025). Versatile Molecular Engineering of In Situ Cross-Linked Multifunctional Electrolytes for Long-Lifetime and Safe Semisolid Lithium Metal Batteries. ACS Nano, 19(14), 14284–14298. https://doi.org/10.1021/acsnano.5c00990

The practical application of semisolid lithium metal batteries is impeded by inadequate ionic conductivity, suboptimal oxidation/reduction stability, and safety concerns of the electrolyte. Herein, a versatile molecular engineering strategy is proposed to construct a robust polymer framework for semisolid electrolytes, which creates highly compatible cross-linked networks by the in situ gelation of concentrated succinonitrile-based plastic crystal electrolytes and multifunctional nitrogen- and fluorine-rich monomers. This strategy allows the electrolyte to promote rapid Li-ion transpsort through weak coordination with the polymer segments. Meanwhile, the strong interactions between the polymer matrix and succinonitrile enhance their mutual solubility, reduce the crystallinity of succinonitrile, and establish fast ion-conductive pathways. The resultant electrolyte induces the formation of LiF/Li3N-rich solid electrolyte interphases and achieves uniform lithium deposition behaviors. Moreover, it mitigates fire risks by cothermally decomposing to produce fire-extinguishing gases (CO2 and NH3) and leveraging the nonflammability of succinonitrile. Significant improvements in electrochemical performance have been observed in Li symmetric, Li||LiFePO4, and Li||LiNi0.8Co0.1Mn0.1O2 cells both at room temperature and high temperature (60 °C). As a demonstration model, this molecular engineering strategy has been successfully applied to enhance thermal stability and safety in Li||LiNi0.8Co0.1Mn0.1O2 pouch cells, offering a promising solution for semisolid lithium metal batteries under extreme conditions.

Publisher Copyright

This research / project is supported by the Singapore National Research Foundation - NRF Investigatorship
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
Grant Reference no. : M23L9b0052

This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Nano, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see 10.1021/acsnano.5c00990.

https://oar.a-star.edu.sg/communities-collections/articles/23498

1936-0851
1936-086X

Institute of Materials Research and Engineering