SULFIDE SOLID ELECTROLYTES, PREPARATION METHODS THEREOF, AND ALL-SOLID-STATE RECHARGEABLE BATTERIES

A sulfide solid electrolyte, including sulfide solid electrolyte particles, and a coating layer on a surface of the sulfide solid electrolyte particles, wherein the coating layer includes CO and PO, and a ratio of a maximum peak intensity of the CO to a peak intensity of the PO in infrared spectroscopy is about 0.5 to about 1.