Formation of interfacial contact with ductile Li3BO3-based electrolytes for improving cyclability in all-solid-state batteries

Highly safe all-solid-state batteries are constructed using oxide electrolytes because of their high chemical and electrochemical stabilities. Previously, we have developed various Li3BO3-based glass-ceramic electrolytes with high ductility and conductivity. In this study, we focus on the importance of electrode/electrolyte interfacial contacts in all-solid-state batteries. All-oxide solid-state cells (Li-In/LiNi1/3Mn1/3Co1/3O2) with Li3BO3-based glass-ceramic electrolytes, are fabricated simply by pressing at room temperature. Furthermore, the effects of the ductility and ionic conductivity of glass-ceramic electrolytes on the charge-discharge properties of all-solid-state batteries are investigated. The 33Li(3)BO(3)center dot 33Li(2)SO(4)center dot 33Li(2)CO(3) (mol%) glass-ceramic electrolyte shows lower ionic conductivity and better ductility than the 90Li(3)BO(3)center dot 10Li(2)SO(4) electrolyte. The all-solid-state cells using these electrolytes operate as secondary batteries at 100 degrees C. However, better cycle performance is obtained with cells using the former electrolyte. Formation of well-contacted electrode/electrolyte interfaces when using highly ductile electrolytes leads to enhanced electrochemical performance of bulk-type all-solid-state batteries.