Towards ambient temperature operation of Li metal batteries using UV-Crosslinked single-ion electrospun electrolytes

Xuan Song; Bingfei Nan; Dongxia Li; Qiong Lin; Xiangfeng Sun; Yuxin Xue; Qingbin Cao; Xuefeng Gui; Kai Xu

doi:10.1016/j.jcis.2023.05.010

Towards ambient temperature operation of Li metal batteries using UV-Crosslinked single-ion electrospun electrolytes

J Colloid Interface Sci. 2023 Oct:647:134-141. doi: 10.1016/j.jcis.2023.05.010. Epub 2023 May 9.

Authors

Xuan Song¹, Bingfei Nan², Dongxia Li³, Qiong Lin³, Xiangfeng Sun³, Yuxin Xue³, Qingbin Cao⁴, Xuefeng Gui⁵, Kai Xu⁵

Affiliations

¹ Guangzhou Institute of Chemistry, Chinese Academy of Sciences, Guangzhou 510650, China; University of Chinese Academy of Sciences, Beijing 100049, China; The State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
² Department of Physics, Universitat de Barcelona, 08028 Barcelona, Spain.
³ Guangzhou Institute of Chemistry, Chinese Academy of Sciences, Guangzhou 510650, China; University of Chinese Academy of Sciences, Beijing 100049, China.
⁴ The State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
⁵ Guangzhou Institute of Chemistry, Chinese Academy of Sciences, Guangzhou 510650, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: guixf@gic.ac.cn.

PMID: 37247477
DOI: 10.1016/j.jcis.2023.05.010

Abstract

In spite of the fact that lithium metal batteries (LMBs) facilitate the diversification of energy storage technologies, their electrochemical reversibility and stability have long been constrained by side reactions and lithium dendrite problems. While single-ion conducting polymer electrolytes (SICPEs) possess unique advantages of suppressing Li dendrite growth, they deal with difficulties in practical applications due to their slow ion transport in general application scenarios at ∼25 °C. In this study, we develop novel bifunctional lithium salts with negative sulfonylimide (-SO₂N(^-)SO₂-) anions mounted between two styrene reactive groups, which is capable of constructing 3D cross-linked networks with multiscale reticulated ion nanochannels, resulting in the uniform and rapid distribution of Li⁺ ions in the crosslinked electrolyte. To verify the feasibility of our strategy, we designed PVDF-HFP-based SICPEs and the obtained electrolyte exhibits high thermal stability, outstanding Li⁺ transference number (0.95), pleasing ionic conductivity (0.722 mS cm^-1), and broad chemical window (greater than5.85 V) at ambient temperature. As a result of the electrolyte structural merits, the Li||LFP cells displayed excellent cycling stability (96.4% reversible capacities after 300 cycles at 0.2C) without additional auxiliary heating. This ingenious strategy is expected to providing a new perspective for advanced performance and high safety LMBs.

Keywords: Electrospun; Lithium metal batteries; Single-ion conducting polymer electrolytes; Thiol-ene click reaction.