Fluorinated Deep Eutectic Polymer Electrolytes with Hydrogen Bonds‐Rich Networks: Realizing Targeted Management of Primary Solvation Sheath Migration

Abstract The exploration of Li ⁺ transport mechanism in the bulk and the interface holds the key to achieving rapid Li ⁺ transport and desolvation kinetics. However, little is still known about that in gel polymer electrolytes enriched with hydrogen bond networks. Here, fluorinated gel‐deep eutectic solvated (FG‐DES) polymer electrolytes are fabricated for exploring the aforementioned mechanism by spectroscopy and molecular dynamics (MD) simulation. The observation provides an insight into the formation of [Li ⁺ ···solvent] primary solvation sheath and the migration of the sheath along the polymer backbone in a fast and oriented manner through dissociation and complexation of the hydrogen bonds between solvents and polymer skeletons. Furthermore, the polymer backbone exerts a targeted management by pulling and anchoring effect on protonic solvent molecules, accelerating the desolvation process and reducing side reactions. Based on this, the capacity retention of the assembled LFP||Li is 94.7% after 600 cycles at 1 C, and the retention of NCM622||Li is 87.1% after 200 cycles, which demonstrats its excellent compatibility in lithium metal cells. This work offers a design basis for achieving rapid Li ⁺ mobility and deposition in a hydrogen bonds‐rich environment.