Oxygen Evolution Barrier and Lithium-Ion Transport Promotion Effects of MOF-LATP Composite Solid Electrolyte for High-Energy-Density Lithium Batteries

, a lithium-ion transference number of 0.72, and a wide electrochemical window of 5.4 V. When applied in NCM811||C pouch cells, the composite separator significantly suppresses gas evolution during overcharge (1C, 3 h) and maintains 90.8% capacity retention after 100 cycles at 1C. Furthermore, NCM811||Li cells achieve 79.4% retention after 500 cycles at 1C. Interfacial analysis confirms that the MOF layer effectively captures cathode-released oxygen, while synergistically cooperating with the PVDF-HFP layer to construct a stable, LiF-rich solid electrolyte interphase (SEI), thereby significantly boosting the electrochemical performance and safety of high-voltage lithium-ion batteries.