High-rate lithium cycling in a scalable trilayer Li-garnet-electrolyte architecture

Solid-state lithium batteries promise to exceed the capabilities of traditional Li-ion batteries in safety and performance. However, a number of obstacles have stood in the path of solid-state battery development, primarily high resistance and low capacity. In this work, these barriers are overcome through the fabrication of a uniquely microstructured solid electrolyte architecture based on a doped Li7La3Zr2O12 (LLZ) ceramic Li-conductor. Specifically, a porous-dense-porous trilayer structure was fabricated by tape casting, a scalable roll-to-roll manufacturing technique. The dense (>99%) center layer can be fabricated as thin as similar to 10 mu m and blocks dendrites over hundreds of cycles. The microstructured porous layers serve as electrode supports and increase the mechanical strength by similar to 9x, making the cells strong enough to handle with ease. Additionally, the porous layers multiply the electrode-electrolyte interfacial surface area by >40x compared to a typical planar interface. Lithium symmetric cells based on the trilayer architecture were cycled at room temperature and achieved area-specific resistances (similar to 7 Omega-cm(2)) dramatically lower, and current densities dramatically higher (10 mA/cm(2)), than previously reported literature results. Moreover, to demonstrate scalability a large-format cell was fabricated with lithium metal in one porous layer and a sulfur electrode with conductive carbon and an ionic liquid interface in the other, achieving 1244 mAh/g S utilization and 195 Wh/kg based on total cell mass, showing a promising path to commercially viable, intrinsically safe lithium batteries with high specific energy and high energy density.