Garnet Type Solid State Electrolytes: Materials, Interfaces, and Batteries.
Solid state batteries with desirable advantages, including high energy density, wide temperature tolerance, and fewer safety concerns, have been considered as a promising energy storage technology to replace organic liquid electrolyte dominated Li ion batteries. Solid state electrolytes (SSEs) as the most critical component in solid state batteries largely lead the future battery development. Among different types of solid state electrolytes, garnet type Li7La3Zr2O12 (LLZO) solid state electrolytes have particularly high ionic conductivity (10 3 to 10 4 S/cm) and good chemical stability against Li metal, offering a great opportunity for solid state Li metal batteries. Since the discovery of garnet type LLZO in 2007, there has been an increasing interest in the development of garnet type solid state electrolytes and all solid state batteries. Garnet type electrolyte has been considered one of the most promising and important solid state electrolytes for batteries with potential benefits in energy density, electrochemical stability, high temperature stability, and safety. In this Review, we will survey recent development of garnet type LLZO electrolytes with discussions of experimental studies and theoretical results in parallel, LLZO electrolyte synthesis strategies and modifications, stability of garnet solid electrolytes/electrodes, emerging nanostructure designs, degradation mechanisms and mitigations, and battery architectures and integrations. We will also provide a target oriented research overview of garnet type LLZO electrolyte and its application in various types of solid state battery concepts (e.g. Li ion, Li S, and Li air) and we will show opportunities and perspectives as guides for future development of solid electrolytes and solid state batteries.
Chemical reviews