Aqueous tape casting phosphate ceramic electrolyte membrane for high performance all solid-state lithium metal battery

Li1.3Al0.3Ti1.7(PO4)3 (LATP) solid electrolyte has caused great attention because of its low cost, high ionic conductivity, and superior air stability. In this work, high quality LATP ceramic electrolyte membranes are fabricated by an aqueous tape casting technique in the air, in contrast to traditional fabrication methods that are usually inefficient and noncontinuous, this technique provides an environment-friendly, scalable, continuous fabrication route for mass production of ceramic electrolyte membranes. The as-prepared LATP ceramic membrane with a relative density of 95.6 % shows a total Li ionic conductivity of 3.8 × 10−4 S cm−1. Simply coated with a flexible polymer electrolyte film on the surface of the LATP ceramic membrane, the solid-solid interfacial polarization between the LATP ceramic membrane and the electrodes can be well controlled under a reasonable level, leading to excellent battery performance. Discharge capacities of 160.6, 157.6, 151.2, 138.9 and 123.9 mAh g−1 at 0.05, 0.1, 0.2, 0.5 and 1 C rates are achieved, respectively. This study demonstrates a promising strategy for commercializing all-solid-state batteries with a cost-effective and scalable manufacturing technique.