Investigating the electrochemical stability of LiLaZrO solid electrolytes using field stress experiments.

Cubic LiLaZrO (LLZO) garnets are among the most promising solid electrolytes for solid-state batteries with the potential to exceed conventional battery concepts in terms of energy density and safety. The electrochemical stability of LLZO is crucial for its application, however, controversial reports in the literature show that it is still an unsettled matter. Here, we investigate the electrochemical stability of LLZO single crystals by applying electric field stress macro- and microscopic ionically blocking Au electrodes in ambient air.