Balancing Anodic Stability and Cathodic Kinetics in Practical Lithium-Sulfur Batteries With Non-fluorinated Weakly Solvating Solvents

Zhicheng Wang; Shixiao Weng; Haiyang Zhang; Liping Wang; Xu Yao; Haifeng Tu; Dan Huang; Suwan Lu; Lingwang Liu; Jiangyan Xue; Fengrui Zhang; Guan Wu; Jieyun Zheng; Qing Wang; Liquan Chen; Jingjing Xu; Hong Li; Xiaodong Wu

doi:10.1002/advs.202417305

Balancing Anodic Stability and Cathodic Kinetics in Practical Lithium-Sulfur Batteries With Non-fluorinated Weakly Solvating Solvents

Adv Sci (Weinh). 2025 Jul 2:e17305. doi: 10.1002/advs.202417305. Online ahead of print.

Authors

Zhicheng Wang^{1

2}, Shixiao Weng³, Haiyang Zhang^{3

4}, Liping Wang^{2

5}, Xu Yao², Haifeng Tu³, Dan Huang³, Suwan Lu³, Lingwang Liu³, Jiangyan Xue³, Fengrui Zhang^{1

2}, Guan Wu⁴, Jieyun Zheng^{1

2}, Qing Wang⁶, Liquan Chen^{1

2}, Jingjing Xu^{3

7}, Hong Li^{1

2}, Xiaodong Wu^{3

2}

Affiliations

¹ Beijing Advanced Innovation Center for Materials Genome Engineering Key Laboratory for Renewable Energy, Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
² Tianmu Lake Institute of Advanced Energy Storage Technologies Co., Ltd., Liyang, 213300, China.
³ i-lab Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences, Suzhou, 215123, China.
⁴ National Engineering Lab for Textile Fiber Materials & Processing Technology, Zhejiang Sci-Tech University, Hangzhou, 310018, China.
⁵ School of Materials and Energy, University of Electronic Science and Technology of China, Chengdu, 611731, China.
⁶ Department of Materials Science and Engineering, National University of Singapore, Singapore, 117576, Singapore.
⁷ College of Material Science and Engineering, Hohai University, Changzhou, 213000, China.

PMID: 40605416
DOI: 10.1002/advs.202417305

Abstract

The performance of lithium-sulfur (Li-S) batteries is crucially affected by the anodic stability of Li-metal and cathodic conversion kinetics of sulfur-carbon (S/C) composites. Herein, a weakly solvating electrolyte (WSE) with moderate lithium polysulfides (LiPSs) solubility, consisting of 1 M lithium bis(trifluoromethane sulfonyl) imide (LiTFSI) in non-fluorinated solvent of cyclopentyl methyl ether (CPME) and 1,3-dioxolane (DOL) additive, is employed in Li-S batteries to simultaneously achieve high anodic stability and appropriate cathodic kinetics. This WSE exhibits a good capability of suppressing LiPSs shuttling by forming an anions-dominated Li⁺ solvation structure, effectively inducing a stable solid electrolyte interphase (SEI) to guarantee anodic stability of the Li-metal anode. Additionally, the DOL additive in the WSE aids in forming a thin organic-inorganic hybrid cathode electrolyte interphase (CEI) on the surface of S/Li₂S particles, which maintains good conversion kinetics and suppresses dead S/Li₂S growth in the S/C cathode. Consequently, Li-S batteries with the WSE deliver a high initial capacity (≈1208 mAh g^-1), a high average Coulombic efficiency (≈98.6%), and a high capacity retention rate (≈82.4%) over 200 cycles. Stable cycling performance over 100 cycles is also observed in the Li-S pouch cell with the WSE even under harsh conditions.

Keywords: lithium sulfur batteries; long cycle life; shuttle effect; solvation structures; weakly solvating electrolytes.

Abstract

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