Supramolecular Oscillation-Assisted Ion Transport in Solid Electrolytes

Abstract

Solid-state electrolytes are crucial for electrochemical devices, yet the challenge of simultaneously enhancing both ionic conductivity and stability—rather than sacrificing one for the other—remains a critical issue. In this work, a high-performance solid polymer electrolyte (HP-SPE) membrane that successfully integrates exceptional stability with high ionic conductivity was developed. It is based on a polyvinyl butyral (PVB) matrix coupled with (3-glycidyloxypropyl)trimethoxysilane (KH560) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), and was fabricated through an ultra-low residual solvent content drying (ULD) process. The high comprehensive performance of HP-SPE was realized with the help of the binding state of trace residual solvents within LiTFSI and polymer matrix called “supramolecular oscillation-assisted ion transport” mechanism. The HP-SPE achieved an ionic conductivity of 10−5 S/cm at 30 oC (for over two months). The decomposition temperature reached 250 oC, achieving comprehensive improvement in both conductivity and stability. By applying the HP-SPE membrane to the emerging electrochromic devices, the electrochromic devices achieved rapid color switching (3.1 s for coloration and 6.1 s for bleaching), uniform color transition, and steady-state operation without overheating issues for up to 160 hours, the best result reported to date. This work establishes the HP-SPE as a versatile material platform, demonstrating immediate success in electrochromics and revealing significant potential for deployment in next-generation, high-safety solid-state batteries.