Influence of synthesis parameters on crystallization behavior and ionic conductivity of the Li4PS4I solid electrolyte

Superionic solid electrolytes are key to the development of advanced solid-state Li batteries. In recent years, various materials have been discovered, with ionic conductivities approaching or even exceeding those of carbonate-based liquid electrolytes used in high-performance Li-ion batteries. Among the different classes of inorganic solid electrolytes under study, lithium thiophosphates are one of the most promising due to their high Li-ion conductivity at room temperature and mechanical softness. Here, we report about the effect of synthesis parameters on the crystallization behavior and charge-transport properties of Li4PS4I. We show that thermally induced crystallization of Li4PS4I (P4/nmm), starting from the glassy phase 1.5Li(2)S-0.5P(2)S(5)-LiI, adversely affects the material's conductivity. However, both conductivity and crystallization temperature can be significantly increased by applying pressure during the preparation.

Automated summary

Research has shown that applying pressure can significantly increase the conductivity and crystallization temperature of Li4PS4I, thereby affecting its charge-transport properties.