Architecting Host–Guest Synergistic Solid-State Electrolytes Enables Unobstructed Li-Ion Interphase Migration for Lithium Metal Batteries

Abstract

Composite solid-state electrolytes inherit the intrinsic merits of each polymer and the inorganic solid-state electrolyte. However, their combined products are still unsatisfactory due to the unmatched Li-ion transport properties and the absence of structural integrity. Herein, an architectural inorganic–organic solid-state electrolyte (AIOSE) was constructed with highly coordinated Li-ion transport mode, where the primary Li_6.4La₃Zr_1.4Ta_0.6O₁₂ particles were reconstructed as a continuous fast Li-ion transport skeleton, and the assisted organic components, including poly(ethylene glycol) diacrylate, ethylene carbonate, dimethyl carbonate, and lithium difluoro(oxalato) borate, were in situ polymerized into an elastic fast ion filler. The principles of “host–guest synergistic regulating Li-ion transport” and “Li-ion conductivity matched in order of magnitude” can provide continuous two-phase Li-ion transfer channels, achieving a high Li-ion conductivity of 0.58 mS cm^–1 and Li-ion transference number of 0.66 at 25 °C. The Li||AIOSE||Li symmetric cells can be cycled for 1200 h at 0.35 mA cm^–2 without an internal short circuit and hysteresis potential rise. The Li||AIOSE||LiNi_0.8Co_0.1Mn_0.1O₂ solid-state batteries can operate properly at −20 °C with 91.6% capacity retention and maintain 1000 cycles at 20 and 60 °C with 73% capacity retention. Our fabricated strategy validates the effectiveness of the design and showcases enormous potential in solid-state lithium batteries.