SOLID-STATE ELECTROLYTE MATERIAL COMPRISING A CHALCOGENIDE-BASED IONIC-CONDUCTIVE STRUCTURE, PARTICULARLY A SULFIDE-BASED IONIC-CONDUCTIVE STRUCTURE

A solid-state electrolyte material, comprising: a chalcogenide-based ionic-conductive structure comprising: one or more of lithium, sodium, aluminum, magnesium, iron, and potassium; one or more of sulfur, oxygen, selenium, and tellurium; one or more of boron, gallium, antimony, silicon, germanium, tin, phosphorus, and arsenic; and at least one of excess chalcogen and excess chalcogenide incorporated into the chalcogenide-based ionic-conductive structure.