A High-Performance Lithium Oxygen Battery can be Achieved by Facilitating Ion Transport Modulation Using a LiI Solid-State Electrolyte

In this work, we suggest a new design for a composite solid-state electrolyte by adding lithium iodide (LiI) to improve its performance. This method improves how ions move and reduces resistance at the surface by making lithium aluminum titanium phosphate (LATP) inorganic fillers work better with poly (PVDF-HFP) polymer matrices. Electrolyte (HSE-2) containing 10wt% LiI exhibits excellent overall performance, with an ionic conductivity of 0.535 mS·cm⁻¹, an enhanced lithium ion transference number of 0.589, and a stabilized overpotential of the Li/HSE-2/Li symmetric cell at 0.62 mV after cycling for 700 h at a current density of 0.1 mA·cm⁻². The lithium-oxygen battery, which has been assembled on the basis of the HSE-2 lithium-oxygen battery, has achieved 190 stable cycles at 100 mA·g⁻¹ with a discharge capacity of up to 7100 mAh·g⁻¹. The present work elucidates the mechanism by which inorganic materials enhance ion movement in composite solid-state electrolytes and explains how the combination of inorganic materials and polymers improves ion movement in composite solid-state electrolytes by adjusting the interface and filling pores with LiI. The study focuses on designing electrolytes for high-security and long-life solid-state lithium-oxygen batteries.