Confinement-Regulated Lamellar Interphase with Enhanced Dielectric Environments for Lithium Metal Batteries

The natural solid electrolyte interphase (SEI) typically consists of complex ingredients and disordered structures, posing significant challenges in achieving rapid Li⁺ desolvation and uniform Li⁺ deposition, which leads to uncontrolled electrolyte decomposition and lithium dendrite growth. This study designs a lamellar sieving interphase with enhanced dielectric environments, achieved through confinement-regulated polymer chain conformation, effectively decoupling the Li⁺ desolvation and deposition processes. The lamellar interphase selectively sieves solvent molecules, promoting Li⁺ desolvation and enhancing the dissociation of lithium salts. The nanofluidic channel within the confined lamella promotes ion transfer, ensuring uniform ion distribution and improving mechanical stability. Lithium metal anodes with this lamellar interphase exhibit exceptional stability during stripping/plating cycling, maintaining stable performance for over 2000 h at 2 mA cm^-2. Furthermore, LiFePO₄||Li and NCM811||Li batteries assembled with the lamellar interphase demonstrate a stable reversible capacity and cycling performance. This study presents a lamellar interphase design, offering tunable confinement and regulation mechanisms to decouple the Li⁺ desolvation and deposition processes with stable cycling performance in lithium metal batteries.