Direct Ink Writing of Li_1.3 Al_0.3 Ti_1.7 (PO₄ )₃ -Based Solid-State Electrolytes with Customized Shapes and Remarkable...

All-solid-state lithium batteries have received extensive attention due to their high safety and promising energy density and are considered as the next-generation electrochemical energy storage system. However, exploring solid-state electrolytes in customized geometries without sacrificing the ionic transport is significant yet challenging. Herein, various 3D printable Li_1.3 Al_0.3 Ti_1.7 (PO₄ )₃ (LATP)-based inks are developed to construct ceramic and hybrid solid-state electrolytes with arbitrary shapes as well as high conductivities. The obtained inks show suitable rheological behaviors and can be successfully extruded into solid-state electrolytes using the direct ink writing (DIW) method. As-printed free-standing LATP ceramic solid-state electrolytes deliver high ionic conductivity up to 4.24 × 10^-4  S cm^-1 and different shapes such as "L", "T," and "+" can be easily realized without sacrificing high ionic transport properties. Moreover, using this printing method, LATP-based hybrid solid-state electrolytes can be directly printed on LiFePO₄ cathodes for solid-state lithium batteries, where a high discharge capacity of 150 mAh g^-1 at 0.5 C is obtained. The DIW strategy for solid-state electrolytes demonstrates a new way toward advanced solid-state energy storage with the high ionic transport and customized manufacturing ability.