Enabling a Durable Electrochemical Interface via an Artificial Amorphous Cathode Electrolyte Interphase for Hybrid Solid/Liquid Lithium‐Metal Batteries

• Published in: Angewandte Chemie International Edition Vol. 59; no. 16; pp. 6585 - 6589
• Main Authors: Liang, Jia‐Yan, Zhang, Xu‐Dong, Zeng, Xian‐Xiang, Yan, Min, Yin, Ya‐Xia, Xin, Sen, Wang, Wen‐Peng, Wu, Xiong‐Wei, Shi, Ji‐Lei, Wan, Li‐Jun, Guo, Yu‐Guo
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 16.04.2020
• Edition: International ed. in English
• Subjects: amorphous phases; cathode electrolyte interphase; Cathodes; Chemical compatibility; Density; Electrochemistry; Electrolytes; Energy storage; hybrid solid/liquid batteries; Interface stability; interfacial electrochemistry; interfacial stability; Interphase; Liquid lithium; Lithium; Surface structure; interfacial stability; amorphous phases; interfacial electrochemistry; cathode electrolyte interphase; hybrid solid/liquid batteries
• ISSN: 1433-7851; 1521-3773; 1521-3773
• DOI: 10.1002/anie.201916301

A hybrid solid/liquid electrolyte with superior security facilitates the implementation of high‐energy‐density storage devices, but it suffers from inferior chemical compatibility with cathodes. Herein, an optimal lithium difluoro(oxalato)borate salt was introduced to build in situ an amorphous cathode electrolyte interphase (CEI) between Ni‐rich cathodes and hybrid electrolyte. The CEI preserves the surface structure with high compatibility, leading to enhanced interfacial stability. Meanwhile, the space‐charge layer can be prominently mitigated at the solid/solid interface via harmonized chemical potentials, acquiring promoted interfacial dynamics as revealed by COMSOL simulation. Consequently, the amorphous CEI integrates the bifunctionality to provide an excellent cycling stability, high Coulombic efficiency, and favorable rate capability in high‐voltage Li‐metal batteries, innovating the design philosophy of functional CEI strategy for future high‐energy‐density batteries. The CEI's advantage: An amorphous cathode electrolyte interphase (CEI) with superior chemical compatibility and plasticity was formed via in situ LiDFOB conversion. It endows high‐voltage hybrid solid/liquid batteries with significantly enhanced interfacial stability, durability, and dynamics.