Ceramic-based solid electrolytes ar

Ceramic-based solid electrolytes are a promising class of materials that enable safer Li metal batteries because they are nonflammable and have a large range of electrochemical stability.[4,8] Furthermore, ceramic electrolytes have Li transference numbers of unity and high elastic moduli compared to polymeric electrolytes, which may be crucial to suppress dendrite growth.[5] Among various ceramic solid electrolytes,[4,8–14]sodium super ionic conductor (NASICON)-type oxide electrolytes have been highlighted as promising candidates because they exhibit ionic conductivities near 10−4 S cm−1 at room temperature and good chemical stability against water and air.[4,8,11–14] Nevertheless, sintering of these oxide electrolytes requires high temperature, above 800 °C, to achieve high densities and high ionic conductivities.[9,12,14–17] Such a sintering process has obvious limitations, including Li loss, impurity phase formation, incompatibility with organic materials, difficulties in integrating all-solid-state batteries with composite cathodes, and high processing cost.