Operando X-Ray Imaging of Solid-State Battery Materials and Interfaces

Solid-state batteries (SSBs) offer higher energy density and enhanced safety compared to conventional lithium-ion batteries. However, their interfacial evolution and degradation mechanisms differ significantly from those in liquid-electrolyte systems, requiring advanced techniques to monitor material and interface behavior during operation. 1 X-ray computed tomography (XCT) enables non-destructive, three-dimensional imaging of buried interfaces, providing a comprehensive view of the SSB cell stack and linking structural changes to interfacial behavior. In this presentation, I will discuss how operando X-ray tomography can reveal structural and morphological changes at various SSB interfaces. 2 First, I will demonstrate how operando tomography distinguishes between uniform and dendritic lithium deposition in anode-free SSB cells, showing how interphase growth affects electrochemical performance and mechanical stability. 3,4 Next, I will present results from silicon-based alloy anodes, showing the dynamic formation of cracks in silicon anodes, including interfacial cracks that can significantly degrade cell performance. 5 Finally, I will discuss microstructural evolution and volume changes in conversion-type cathode composites. By combining operando imaging with pressure evolution studies, this work provides insights into interfacial reaction pathways and degradation mechanisms in high-capacity cathode materials. Overall, these findings underscore the importance of real-time understanding microscale material evolution to enhance the electrochemical performance of SSBs. References: 1 E. P. Alsaç, D. L. Nelson, S. G. Yoon, K. A. Cavallaro, C. Wang, S. E. Sandoval, U. D. Eze, W. J. Jeong and M. T. McDowell, Chem. Rev. , 2025, 125 , 2009–2119. 2 J. A. Lewis, F. J. Q. Cortes, Y. Liu, J. C. Miers, A. Verma, B. S. Vishnugopi, J. Tippens, D. Prakash, T. S. Marchese, S. Y. Han, C. Lee, P. P. Shetty, H.-W. Lee, P. Shevchenko, F. De Carlo, C. Saldana, P. P. Mukherjee and M. T. McDowell, Nat. Mater. , 2021, 20 , 503–510. 3 S. E. Sandoval, J. A. Lewis, B. S. Vishnugopi, D. L. Nelson, M. M. Schneider, F. J. Q. Cortes, C. M. Matthews, J. Watt, M. Tian, P. Shevchenko, P. P. Mukherjee and M. T. McDowell, Joule , 2023, 7 , 2054–2073. 4 S. Sandoval, D. Nelson, H. Sridhara, T. Thomas, J. Lewis, K. Cavallaro, P. Shevchenko, N. Dasgupta, F. Usseglio-Viretta, D. Finegan and M. McDowell, ChemRxiv , 2025, preprint, DOI: 10.26434/chemrxiv-2025-1hflr. 5 D. L. Nelson, S. E. Sandoval, J. Pyo, D. Bistri, T. A. Thomas, K. A. Cavallaro, J. A. Lewis, A. S. Iyer, P. Shevchenko, C. V. Di Leo and M. T. McDowell, ACS Energy Lett. , 2024, 9 , 6085–6095.