(167d) MOFs-Derived Filler-Reinforced Composite Polymer Electrolyte for Solid-State Lithium-Sulfur Batteries at Room Temperature

Solid-state composite polymer electrolytes with great thermal and mechanical stabilities for batteries have attracted tremendous attention to overcome the challenges that are associated with liquid electrolytes. Typically, polymers matrices suffer from low ionic conductivity at room temperature and interfacial resistance between the electrodes and the electrolyte. Herein, we investigated a poly (ethylene oxide) (PEO)-based electrolyte that is reinforced by metal−organic frameworks (MOFs) fillers to enhance the ionic conductivity and lower the PEO crystallinity. The composite solid electrolyte contains a PEO (MW 600,000) matrix, MOF fillers based on TiCl₄, VCl₃, NiCl_2, and RuCl₃, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), and ionic 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl imide) (BMIMTFSI) as Ionic liquid (IL). The composite solid electrolytes were characterized by SEM, XRD, and XPS. The composite solid electrolytes possess a high ionic conductivity of 10^-4 S cm^-1 at room temperature. The assembled Li/PEO-MOF-IL/CoS coin cells showed promising specific capacities and cycling stability. Overall, the results demonstrated that the MOFs, together with IL, are effective components for synthesizing solid-state electrolytes for Li-S batteries.