Efficient lithium metal stripping and plating operation capable of maintaining electronic and ionic conductivity is crucial to develop safe lithium metal batteries. However, monitoring lithium metal microstructure evolution during cell cycling is challenging. Here, we report the development of an operando synchrotron X-ray tomographic microscopy method capable of probing in real-time the formation, growth, and dissolution of Li microstructures during the cycling of a Li||Cu cell containing a standard non-aqueous liquid electrolyte solution. The analyses of the operando X-ray tomographic microscopy measurements enable tracking the evolution of deposited Li metal as a function of time and applied current density and distinguishing the formation of electrochemically inactive Li from the active bulk of Li microstructures. Furthermore, in-depth analyses of the Li microstructures shed some light on the structural connectivity of deposited Li at different current densities as well as the formation mechanism of fast-growing fractal Li microstructures, which are ultimately responsible for cell failure.

能够保持电子和离子电导率的高效锂金属剥离和电镀操作对于开发安全的锂金属电池至关重要。然而，监测电池循环过程中锂金属微观结构的演变具有挑战性。在这里，我们报告了原位同步加速器 X 射线层析显微方法的发展，该方法能够在包含标准非水液体的 Li||Cu 电池循环过程中实时探测 Li 微结构的形成、生长和溶解电解质溶液。对原位 X 射线断层扫描显微镜测量的分析能够跟踪沉积锂金属随时间和施加电流密度的变化，并区分电化学非活性锂的形成与活性锂微结构。此外，