Amide Induced Fast‐Ion Transport in Bulk Phases and Interfaces for Polymer‐In‐Ceramic Electrolytes

Abstract Polymer in ceramic (PIC) electrolytes have garnered significant attention due to their advantages over individual inorganic and organic polymer electrolytes. However, the slow movement of Li + on polymer chain segments and the “hard contact” among ceramic particles with irregular surface severely impede the smooth transport of lithium ions. The bipolar character of N‐methyl‐2,2,2‐trifluoroacetamide (MFA) makes it significantly enriched on ceramic surface, accordingly converting the “hard contact” between ceramic particles into a “soft contact” mode, and opening up the ion transport among multiple phases. The structure of fluorine substitution further disperses the negative charge density on carbonyl group from MFA and accelerates the ligand removal of Li + . Accordingly, MFA interconnected PIC electrolyte (MPIC) exhibits an ionic conductivity of 1.13 mS cm −1 and ion transfer number of 0.81 at 30 °C, also delivering remarkable critical current density of 2.6 mA cm −2 . The corresponding full cell can achieve stable cycling at a high current density of 1.2 mA cm −2 and even at −20 °C, it still retains 94% of its capacity after 100 cycles, overcoming the significant temperature limitations. This work paves the way for designing PIC electrolytes with commercial viability by interphase regulation.