Spatiotemporal mapping of microscopic strains and defects to reveal Li-dendrite-induced failure in all-solid-state batteries

Solid-state electrolytes (SSEs) are key to the success and reliability of all-solid-state lithium batteries, potentially enabling improvements in terms of safety and energy density over state-of-the-art lithium-ion batteries. However, there are several critical challenges to their implementation, including the interfacial instability stemming from the dynamic interaction of as-formed dendritic lithium during cycling. For this work, we emphasize the importance of studying the spatial distribution and temporal evolution of strains and defects in crystalline solid-state electrolytes at the micro-scale, and how this affects dendrite growth. A proof-of-principle study is demonstrated using the synchrotron radiation based micro Laue X-ray diffraction method, and a custom-developed in-situ cycling device. Defects and residual strains are mapped, and the evolution of intragranular misorientation is observed. The feasibility of using this technique is discussed, and recommendations for micro-strain engineering to address the Li/SSEs interfacial issues are given. Also, work directions are pointed out with the consideration of combining multi-techniques for poly-therapy.

Automated summary

Solid-state electrolytes (SSEs) are essential for successful and reliable all-solid-state lithium batteries, with potential improvements in safety and energy density compared to current lithium-ion batteries. However, implementing SSEs faces several challenges, including interfacial instability caused by the interaction of dendritic lithium during cycling. This study emphasizes the importance of studying the spatial distribution and temporal evolution of strains and defects in crystalline SSEs at the micro-scale, and how they affect dendrite growth.