All-Solid-State Lithium Secondary Batteries Using NiS-Carbon Fiber Composite Electrodes Coated with Li₂S–P₂S₅ Solid Electrolytes by Pulsed Laser Deposition

Abstract

Composite materials including NiS active materials, sulfide-based solid electrolytes (SE), and conductive additives (VGCF: vapor grown carbon fiber) were prepared by coating a highly conductive Li(2)S-P(2)S(5) solid electrolyte onto NiS-VGCF composite using pulsed laser deposition (PLD). From scanning electron microscopy, NiS nanoparticles were on VGCF surface after coating of solid electrolytes using PLD. All-solid-state cells using the SE-coated NiS-VGCF composite and the uncoated NiS-VGCF composite were fabricated, and then the coating effects on the electrochemical performance by forming the SE thin film onto the NiS-VGCF composite were investigated. At a high current density of 3.8 mA cm(-2) (corresponding to ca. 1 C), an all-solid-state cell fabricated using the SE-coated NiS-VGCF composite as a working electrode showed the initial discharge capacity of 300 mA h g(-1), and exhibited better cycle performance than the cell using the uncoated NiS-VGCF composite.