Recovering the Ionic Conductivity of Oxygen‐Doped Li3.25InCl5.75O0.25 Electrolyte through Heat Treatment: Reconstructing the Structure Damaged by Moisture

• DOI: 10.1002/cssc.202500495
• Publication Date: 2025-05-02T15:01:14Z
• Authors: Miao Deng; Shiyu Liu; Siwu Li; Wenwen Hu; Ziyu Lu; Ziling Jiang; Lin Li; Kunpeng Tang; Lei Shi; Qiyue Luo; Haitao Li; Jie Yang; Chen Liu; Chuang Yu
• Keywords: Electrochemical window; Fast ion conductor

Metal halide solid‐state electrolytes (MHSEs), especially oxyhalides, possess a broad electrochemical stability window, optimized interfacial compatibility and suitability for high‐voltage cathode materials, making them promising candidates next‐generation all‐solid‐state lithium metal batteries (ASSBs). However, their commercialization is still hindered by several critical technical challenges, the significant moisture sensitivity. In this study, damage to structure performance of Li3.25InCl5.75O0.25 electrolyte caused humid air exposure evaluated, heat treatment proposed proven effective in recovering damage. A series spectroscopic experiments reveal that triggers hydrolysis hydration reactions Li3.25InCl5.75O0.25, leading lattice contraction, significantly hindering lithium‐ion transport. After thermal processing at 400 °C, reconstructed, ionic conductivity reaches an 83.5% recovery (7.6×10‐4 S·cm‐1 vs. pristine 9.1×10‐4 S·cm‐1). ASSBs based on repaired demonstrate excellent cycling rate performance, retaining 76.1% capacity after 1000 cycles 2C. The also retains substantial output under extreme temperatures (60 °C/ ‐20 °C), further verifying comprehensive enhancement strategy its engineering application potential.