Dynamic Supramolecular Polymer Electrolyte to Boost Ion Transport Kinetics and Interfacial Stability for Solid‐State Batteries

Abstract

The key hurdle to the practical application of polymeric electrolytes in high‐energy‐density solid lithium‐metal batteries is the sluggish Li+ mobility and inferior electrode/electrolyte interfacial stability. Herein, a dynamic supramolecular polymer electrolyte (SH‐SPE) with loosely coordinating structure is synthesized based on poly(hexafluoroisopropyl methacrylate‐co‐N‐methylmethacrylamide) (PHFNMA) and single‐ion lithiated polyvinyl formal. The weak anti‐cooperative H‐bonds between the two polymers endow SH‐SPE with a self‐healing ability and improved toughness. Meanwhile, the good flexibility and widened energy gap of PHFNMA enable SH‐SPE with efficient ion transport and superior interfacial stability in high‐voltage battery systems. As a result, the as‐prepared SH‐SPE exhibits an ionic conductivity of 2.30 × 10−4 S cm−1, lithium‐ion transference number of 0.74, electrochemical stability window beyond 4.8 V, and tensile strength up to 11.9 MPa as well as excellent adaptability with volume change of the electrodes. In addition, no major electrolyte decomposition inside batteries made from SH‐SPE and LiNi0.8Mn0.1Co0.1O2 cathode can be observed in the in situ differential electrochemical mass spectrometry test. This study provides a new methodology for the macromolecular design of polymer electrolytes to address the interfacial issues in high‐voltage solid batteries.

Ionic Liquid Crystal–Polymer Composite Electromechanical Actuators: Design of Two-Dimensional Molecular Assemblies for Efficient Ion Transport and Effect of Electrodes on Actuator Performance

“…The pursuit of efficient ion transport pathways within organic and inorganic thin films has garnered significant attention as a strategic approach to improving energy efficiency in batteries, energy harvesting, actuators, water treatments, and more. − In the realm of energy device technologies, various nanostructured polymers have been recognized for their ability to provide high ionic conductivity and mechanical robustness. This category encompasses block ionomers, ionic covalent organic frameworks, supramolecular polymers, and ionic liquid crystalline (LC) polymers. − Among them, liquid crystals stand out as particularly promising due to their large-area orientation achievable through diverse external stimuli such as mechanical shear, light, and electric and magnetic fields. − Nanostructured LC polymers featuring continuous ion-conductive channel networks have been prepared by photopolymerization of thermotropic liquid crystals tethering oligo­(ethylene oxide) chains complexed with lithium salts and lyotropic liquid crystals incorporating liquid electrolytes such as ionic liquids and cyclic carbonates . However, the development of flexible and mechanically durable LC polymer membranes for soft actuator applications is still in its early stage.…”