Press Releases | May 13, 2022

Rapid Synthesis of Highly Ion Conductive Li₇P₃S₁₁ Solid Electrolyte

A research group in the doctoral program of Toyohashi University of Technology's Department of Electrical and Electronic Information Engineering that includes a doctoral student Hirotada Gamo and specially appointed assistant professor Jin Nishida, specially appointed associate professor Atsushi Nagai, assistant professor Kazuhiro Hikima, professor Atsunori Matsuda and others, developed a large-scale manufacturing technology of Li₇P₃S₁₁ solid electrolytes for all-solid-state lithium-ion secondary batteries. This method involves the addition of an excessive amount of sulfur (S) along with Li₂S and P₂S₅, the starting materials of Li₇P₃S₁₁, to a solvent containing a mixture of acetonitrile (ACN), tetrahydrofuran (THF) and a slight amount of ethanol (EtOH). This helped to shorten the reaction time from 24 hours or longer to only two minutes. The final product obtained using this method is highly pure Li₇P₃S₁₁ without an impurity phase that showed high ionic conductivity of 1.2 mS cm^-1 at 25 °C. These results enable us to produce a large quantity of sulfide solid electrolytes for all-solid-state batteries at low cost. The results of the research were published online by Advanced Energy and Sustainability Research on April 28, 2022.

Full text: Development for Novel Large-Scale Manufacturing Technology of Sulfide Solid Electrolytes
TUT website: Press release