Powder Joining Technologies for Realizing Solid-State Batteries

Abstract

Solid electrolytes provide not only high reliability but also high energy density and power density to lithium-ion batteries, because they are nonflammable and only lithium ions are mobile species in solid electrolytes. Essential materials to realize solid-state batteries are solid electrolytes with high ionic conductivities. Vigorous studies have increased the ionic conductivities in various solid electrolyte systems to be comparable to that of organic-solvent electrolytes employed in current lithium-ion batteries. However, even such high ionic conductivities do not lead to high performance of solid-state batteries without interface between the battery materials showing fast ionic conduction. Powder joining technologies are very important to form the conductive interfaces, which will be established by collaboration between materials and process researchers.