Facile interfacial adhesion enabled LATP-based solid-state lithium metal battery

As a low-cost fast lithium ionic conductor with high shear modulus and ionic conductivity, Li1.3Al0.3Ti1.7(PO4)3 (LATP) is supposed to be one of the most promising ceramic electrolytes for high-energy solid-state batteries. However, the chemical reaction with lithium metal and the high interfacial impedance with solid electrodes make the ceramic electrolyte difficult to straightly apply to lithium metal batteries. Herein, a facile interfacial adhesion strategy is proposed to solve the addressed issues. The sticky polyethylene oxide (PEO) thin layer is served as interfacial adhesive to link the compact LATP ceramic electrolyte and the solid electrodes in consideration of its acceptable Li+ conducting capability and perfect compatibility with the tailored materials. Meantime, the PEO adhesive instead of PVDF binder is employed to glue the cathode components, enhancing the affinity to the PEO interlayer. As a result, the solid/solid interfacial resistance is decreased by two orders of magnitude. The solid-state Li/LATP/LiFePO4(LFP) cell with PEO adhesion is successfully activated, and exhibits steady cycling performance with high reversible capacity at the current no more than 0.5 C. As proposed interfacial adhesion strategy is simple but efficient to enable solid-state lithium metal batteries.