Decomposition of Trace Li₂CO₃ During Charging Leads to Cathode Interface Degradation with the Solid Electrolyte LLZO

A major challenge for lithium‐containing electrochemical systems is the formation of lithium carbonates. Solid‐state electrolytes circumvent the use of organic liquids that can generate these species, but they are still susceptible to Li 2 CO 3 formation from exposure to water vapor and carbon dioxide. It is reported here that trace quantities of Li 2 CO 3 , which are re‐formed following standard mitigation and handling procedures, can decompose...