Fast Lithium-Ion Conducting Glass-Ceramics in the System Li2 S ­ SiS2 ­ P 2 S 5

Abstract

Novel glass-ceramics solid electrolytes were prepared from mechanically milled glassy powders in the ternary system Li 2 S ­ SiS 2 ­ P 2 S 5 . With an increase in the heat-treatment temperature, an ambient temperature conductivity of the obtained glass-ceramics reached 1.2 × 10 − 3 S cm − 1 , which is higher than the maximum conductivity of the solid solutions in the system Li 4 SiS 4 ­ Li 3 PS 4 . The enhancement on conductivity by heat-treatment over the crystallization temperature is due to the formation of the highly conductive crystalline phase with the same superlattice structure as the thio-LISICON phase of Li 4 − x Ge 1 − x P x S 4 ( 0.6 < x < 0.8 ) showing high conductivities over 10 − 3 S cm − 1 at room temperature. © 2003 The Electrochemical Society. All rights reserved.