Universal F4-modified Strategy on Metal Organic Framework to Chemical Stabilize Pvdf-Hfp as Quasi-Solid-State Electrolyte.

Solid-state electrolytes (SSEs) based on metal organic framework (MOF) and polymer mixed matrix membranes (MMMs) have shown great promotions in both lithium-ion conduction and interfacial resistance in lithium metal batteries (LMBs). However, the unwanted structural evolution and the and the obscure electrochemical reaction mechanism among two phases limit their further optimization and commercial application. Herein, fluorine-modified zirconium MOF with diverse F-quantities were synthesized, denoted as Zr-BDC-F x (x = 0, 2, 4), to assemble high performance quais-solid-state electrolytes (QSSEs) with PVDF-HFP. The chemical complexation of F-sites in Zr-BDC-F 4 stabilized PVDF-HFP chains in β-phase and disordered oscillation with enhanced charge transfer and Li transmit property. Besides, the porous confinement and electronegativity of F-groups enhanced the capture and dissociation of TFSI - anions and the homogeneous deposition of LiF solid electrolyte interphase (SEI), promoting the high-efficient transport of Li + ions and inhibiting the growth of Li dendrites. As a result, Zr-BDC-F 4 /PVDF-HFP QSSEs delivered high Li + conductivity of 5.27 × 10 -4 S cm -1 and superb maintained specific capacities of 145.3 mAh g -1 at 1 C in Li||LFP coin cells after 300 cycles. Even in the pouch cell, the high specific capacity of 121.9 mAh g -1 at 2 C was achieved with the high stability beyond 300 cycles. Moreover, high-voltage NCM-811//Li and high-loading LFP//Li (high LFP mass loading of 6.82 mg cm -2 ) quasi-solid electrolyte deliver outstanding stable electrochemical performances. More importantly, the universality of F 4 -modified strategy the was confirmed by assembling Zn-BDC-F x , Ce-BDC-F x and Fe-BDC-F x (x = 0, 4) QSSEs, which also displayed greatly enhanced 125, 119 and 120 mAh g -1 at 0.5 C in Li||LFP coin cells with high stabilities, respectively. This article is protected by copyright. All rights reserved.