Cruising in ceramics—discovering new structures for all-solid-state batteries—fundamentals, materials, and performances

Energy storage research has drawn much attention recently due to increasing demand for carbon neutral electrical energy from renewable energy sources such as solar, wind, and hydrothermal. Various electrochemical energy storage and conversion technologies are being considered for their integration into smart grid systems, of which batteries seem to play a vital role due to their wide range of energy densities. In this review, we provide the current status and recent advances in solid-state (ceramic) electrolytes based on inorganic compounds for all-solid-state batteries. This paper is specifically focused on the fundamentals, materials, and performances of solid electrolytes in batteries. A wide spectrum of inorganic solid-state electrolytes is presented in terms of their chemical composition, crystal structure, and ion conduction mechanism. Furthermore, the advantages and main issues associated with different types of inorganic solid electrolytes, including β-alumina, NASICON and LISICON-type, perovskites, and garnet-type for all-solid-state batteries are presented. Among these solid electrolytes, Zr and Ta-based Li-stuffed garnets exhibit high Li-ion conductivity, electrochemical stability window (up to 6 V/Li at room temperature), and chemical stability against reaction with molten elemental Li. However, their stability under humidity and carbon dioxide should be improved to decrease the fabrication and operational costs.</p

Solid-State electrolytes:Structural approach

The chapter systematically describes how the structural framework dictates the pathways for ion mobility (e.g., 1D, 2Dand 3D) in solid-state electrolytes. In lithium-stuffed garnets, for example, Li+-ion shows three-dimensional nature of ion transport; whereas, the motion of same Li+-ion occurs in one-and two-dimensions in β-eucryptite (LiAlSiO4) and Li3N, respectively. In addition to Li+-ion, Na+, H+ and O2-ion-conducting solid-state electrolytes are also introduced in the chapter recognizing their greater importance on developing novel materials for renewable energy applications.</p