Engineering of Covalently Bonded Electrode/Electrolyte for Inorganic‐Based Solid‐State Lithium Batteries

Abstract Solid‐state electrolytes have garnered significant attention due to their inherent advantages in safety and electrochemical stability. Despite these benefits, the interfacial issues between the electrode and the solid‐state electrolyte continue to hinder the widespread application of solid‐state lithium batteries. The lack of effective interfacial contact, particularly in inorganic solid electrolytes (ISEs), remains a critical barrier to achieving optimal battery performance. This study proposes a strategy to address this challenge by constructing a covalent electrode/ISE interface. Strengthening the interactions between the cathode and ISE reduces interfacial resistance and enhances electrochemical stability, leading to significant improvements in battery performance. The resulting solid‐state lithium battery, featuring a stable covalent coupling at the electrode/ISE interface, demonstrates outstanding cycling stability, retaining 85% of its initial capacity after 700 cycles at 1 C. This work not only provides new insights into overcoming interfacial resistance in ISEs but also offers a promising approach for the development of high‐performance solid‐state lithium batteries.