Garnet Electrolyte Surface Degradation and Recovery

• DOI: 10.1021/acsaem.8b01723
• Publication Date: 2018-11-30T21:38:21Z
• Authors: Lei Cheng; Miao Liu; Apurva Mehta; Huolin Xin; Feng Lin; Kristin Persson; Guoying Chen; Ethan J. Crumlin; Marca Doeff
• Keywords: Inert gas; Inert; Degradation

Ceramic materials based on the garnet structure Li7La3Zr2O12 (LLZO) show great promise as lithium-ion conducting electrolytes for solid-state lithium batteries. However, these exhibit surface degradation when exposed to air and moisture, which adversely impacts their functioning in operating devices. In this work, we use several depth-profiling situ techniques probe nature of reactions that occur aluminum (Al)-substituted LLZO is air. These experiments a proton exchange reaction occurs near leads change its chemistry structure, concomitant with formation Li2CO3. But can be readily reversed by heating samples at 250 °C under an inert atmosphere recover structure. Symmetrical cells containing treated way exhibited much lower area specific impedances than those air-exposed without treatment, confirming reversal process. Our results process rejuvenate surface, opens possibility integrating material