Toward the Practical and Scalable Fabrication of Sulfide‐Based All‐Solid‐State Batteries: Exploration of Slurry Process and Performance Enhancement Via the Addition of LiClO₄

Abstract Sulfide‐based all‐solid‐state batteries (ASSBs) have a wide application prospect because of the advantages of higher energy density and better intrinsic safety over conventional lithium‐ion batteries (LIBs). The compatibility of sulfide‐based electrolytes with various organic solvents and the possibilities of the slurry coating process with these systems remain veiled that limits the large‐scale fabrication of sulfide‐based ASSBs. In this study, polyvinylidene fluoride (PVDF) binder and isobutyl isobutyrate (IBB) are selected as the combination of binder and solvent to achieve scalable slurry process after examining the chemical and electrochemical compatibility of Li₆PS₅Cl (LPSC) solid electrolyte, PVDF, and IBB. A comparative investigation of sheet‐type LiNi_0.83Co_0.11Mn_0.06O₂ (NCM811) electrodes and pellet‐type NCM811 electrodes shows that PVDF hinders the transport of Li⁺ and electron, but it benignantly works as a buffer layer, which alleviates the side reaction in the composite cathode electrode. Further, PVDF is modified by LiClO₄ to facilitate interfacial Li⁺ transport, which improves the capacity retention of the cell at 0.5 C to 97.05% after 100 cycles. Finally, NCM811/graphite full‐cell is successfully fabricated by the slurry coating process, which demonstrates the feasibility of practical and scalable fabrication of sulfide‐based ASSBs with slurry process and its performance enhancement effect via LiClO₄ modification.