Electro‐Chemo‐Mechanical Degradation in Solid‐State Batteries: A Review of Microscale and Multiphysics Modeling

Abstract Solid‐state batteries with lithium‐metal anodes have emerged as a promising alternative to traditional lithium‐ion batteries thanks to their enhanced energy density and safety. However, the integration of solid‐state electrolytes is still hindered by mechanical instabilities caused by the rigid nature of the system. Stress and strain can be transferred at the interface between electrodes and solid electrolyte, inducing material damage during cycling. To address this issue, a comprehensive understanding of the interplay between electrochemical reactions and mechanical effects is crucial. In this article, a critical review of various approaches to model the multiphysics behavior of Li‐metal solid‐state batteries is provided by analyzing their advancements and limitations. The focus lies on workflows which simulate the effect of microstructural and material property changes on the degradation processes. Continuum modeling of three key chemo‐mechanical challenges is explored: dendritic growth from Li‐metal anodes, structural instability in composite cathodes, and solid electrolyte degradation caused by the formation of unstable interphases. The conclusion highlights the existing challenges and upcoming trends in multiphysics and microscale modeling of batteries.