Improving the properties of the interface between lithium/sodium anode and solid electrolyte

The development of solid-state lithium and sodium metal batteries necessitates improved the interfacial stability between the solid electrolytes (SEs) and the metallic anodes to enhance their efficiency, safety, and cycle life. This study introduces a simple and cost-effective approach using a porous polyethylene micro-layer (PEML) preloaded with a liquid electrolyte containing metal oxide nanoparticles (MONPs) to enhance the interfacial contact in all-solid-state batteries. LLZO-Ta and Na-β''-alumina were employed as SEs for the lithium and sodium metal cells, respectively. The results indicated that most MONPs reduced the interfacial resistance between the SE and metallic anode, as well as the apparent SEI thickness, leading to improved interfacial properties. Additionally, MONP additives improved the coulombic efficiency (CE) in both cell types; 2 % SnO 2 yielded the highest CE (96.3 %) in the LLZO-Ta cells and 1 % Al 2 O 3 enhanced the CE from 82.1 % to 91.9 % in the Na-β''-alumina cells. These findings highlight the potential of MONP-modified PEMLs for mitigating the interfacial challenges in all-solid-state batteries, thus offering a promising pathway for next-generation energy storage solutions. • A simple approach to improve SE–metal anode interface. • Metal oxide nanoparticles reduced SE-metal anode interfacial resistance. • Metal oxide nanoparticles improved CE% of sodium/lithium metal cells.