Constructing dynamic supramolecular electrolyte with high fluorine and self-healing via phase-locking strategy using in quasi-solid-state lithium-metal batteries

Abstract

Quasi-solid-state lithium metal batteries are considered as improved safety and high theoretical capacity storage devices, still suffer from unsatisfactory electrochemical performance due to incompatible electrolyte-electrodes interface, inhomogeneous and insufficient ionic conductivity of polymer electrolyte. Herein, we construct a stretchable, self-healing, high fluorine quasi‑solid‑state polymer electrolyte under recombination originating from multiple dynamic bonds and phase-locking strategy in the unique dynamic supramolecular structure. C-F bond and benzene ring locking in hard phase not only improves the thermal stability of electrolyte system, but also contributes to the formation of beneficial fluorine-containing interface layer. C=O bonds in the soft phase of supramolecular facilitates the coupling and migration of chain segments to Li⁺, increasing the transport efficiency of Li⁺. Lithium-ion transport networks are established via abundant -CH₂-O-CH₂- in the soft phase and ensures uniform transport of Li⁺ in the microregion. Multiple hydrogen bonds are constructed between hard phase and hard phase that endow the elastomers system with self-healing ability, high tensile strength and strongly stretchable. Fluorine-containing hydrogen bonds induce uniform distribution of charges and accelerating the ions migration at the electrolyte/electrode interface. Benefiting from the improvements in electrolytes, a high capacity and safety of quasi-solid-state lithium metal battery could be achieved.