Protophilic MOF Enables Ni-Rich Lithium Battery Stable Cycling in a High Water/Acid Content.

Trace protic impurities, such as water and hydrofluoric acid (HF), can severely degrade the stable and long cycling of lithium batteries. Therefore, the costly water removal process is inevitably needed throughout production of lithium batteries, leaving the paradox that energy-saving lithium battery technology consumes nonnegligible amounts of energy. Herein, we report a unique ionic metal-organic framework (MOF) enables highly destructive H 2 O/HF-tolerance lithium batteries. The isolated ionic fluorine sites in MOF exhibit unusual protophilicity and efficiently capture ppm-levels H 2 O/HF from the highly polar electrolyte solvents. The resulting MOF-based LiNi 0.6 Mn 0.2 Co 0.2 │Li battery achieves over 300 cycles in the presence of 800 ppm H 2 O or 1107 ppm acidic impurity. This 10-fold longer battery lifespan relative to those for batteries with conventional standard separators demonstrates its excellent electrochemical cycling performance. Our results reveal that the rational use of unique nanoporous features of MOFs could provide new possibilities for long-standing challenges in the lithium battery industry. This article is protected by copyright. All rights reserved.