Insights into Anion‐Solvent Interactions to Boost Stable Operation of Ether‐Based Electrolytes in Pure‐SiOx||LiNi0.8Mn0.1Co0.1O2 Full Cells

• Published in: Angewandte Chemie International Edition Vol. 62; no. 33
• Main Authors: Tian, Yi‐Fan, Tan, Shuang‐Jie, Lu, Zhuo‐Ya, Xu, Di‐Xin, Chen, Han‐Xian, Zhang, Chao‐Hui, Zhang, Xu‐Sheng, Li, Ge, Zhao, Yu‐Ming, Chen, Wan‐Ping, Xu, Quan, Wen, Rui, Zhang, Juan, Guo, Yu‐Guo
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 14-08-2023
• Edition: International ed. in English
• Subjects: Anions; Anodes; Cathode Electrolyte Interphase; Cathodes; Cycles; Dielectric constant; Dipole moments; Electrochemistry; Electrolytes; Electrolytic cells; Lithium; Lithium-Ion Batteries; Oxidation resistance; Silicon-Based Anode; Solid Electrolyte Interphase; Solvents; Stability; Tetrahydrofuran
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202305988

Ether solvents with superior reductive stability promise excellent interphasial stability with high‐capacity anodes while the limited oxidative resistance hinders their high‐voltage operation. Extending the intrinsic electrochemical stability of ether‐based electrolytes to construct stable‐cycling high‐energy‐density lithium‐ion batteries is challenging but rewarding. Herein, the anion‐solvent interactions were concerned as the key point to optimize the anodic stability of the ether‐based electrolytes and an optimized interphase was realized on both pure‐SiOx anodes and LiNi0.8Mn0.1Co0.1O2 cathodes. Specifically, the small‐anion‐size LiNO3 and tetrahydrofuran with high dipole moment to dielectric constant ratio realized strengthened anion‐solvent interactions, which enhance the oxidative stability of the electrolyte. The designed ether‐based electrolyte enabled a stable cycling performance over 500 cycles in pure‐SiOx||LiNi0.8Mn0.1Co0.1O2 full cell, demonstrating its superior practical prospects. This work provides new insight into the design of new electrolytes for emerging high‐energy density lithium‐ion batteries through the regulation of interactions between species in electrolytes.
The anion‐solvent interactions in Li‐ion batteries were promoted in ether‐based electrolyte by applying the small‐anion‐size LiNO3 and tetrahydrofuran with a high ratio of dipole moment to dielectric constant. The designed ether‐based electrolyte showed optimized interphasial stability on the pure‐SiOx anode and NMC811 cathode, thus enabling stable cycling performance of the pure‐SiOx||NMC811 full cell over 500 cycles.