Fuente: Molecules - Revista científica (MDPI) Molecules, Vol. 31, Pages 863: Water-Scavenging Suspended Mediator in Electrolytes for Silicon-Based Lithium-Ion Batteries with High-Nickel Cathode
Molecules doi: 10.3390/molecules31050863
Authors:
Siyuan Peng
Xianzheng Zhang
Weifeng Zhang
Ruiting Su
Wenwu Zou
Chenhui Pan
Limin Zhu
Li Du

Trace amounts of H2O are inevitably introduced during lithium battery manufacturing processes, which induces the hydrolysis of LiPF6, leading to HF formation, which triggers a cascade of deleterious reactions that degrade the solid electrolyte interphase (SEI) and corrode electrode materials. In this work, a water-scavenging electrolyte was constructed by employing a boroxine-linked covalent organic framework (COF) as the suspended phase. The ring-opening reaction of the boroxine ring units in COFs can effectively capture H2O, thereby suppressing the hydrolysis of PF6− and mitigating electrode corrosion caused by HF. Consequently, a Li-metal battery with a high-nickel cathode retained 73% of its initial capacity after 500 cycles at 1 C, and a silicon-based lithium-ion battery with a high-nickel cathode sustained stable cycling over 500 cycles at a high rate of 10 C. This suspension strategy, leveraging a boroxine-linked COF with dual H2O-scavenging capability, offers a scalable and versatile platform for electrolyte engineering toward practical next-generation lithium batteries.