Anode-free solid-state batteries can enable high energy densities and the ability to manufacture high-quality interfaces. However, during in situ anode formation, dynamic mechanical stresses influence the initial Li metal plating morphology. This work utilizes operando 3D video microscopy to characterize electrode morphology during in situ anode formation on garnet Li₇La₃Zr₂O₁₂ (LLZO) solid electrolytes. The coupled morphological evolution and electrochemical signatures are identified and are attributed to changes in stress at the interface. We demonstrate the influence of stress on both thermodynamic and kinetic behaviors at the interface. A mechanistic framework provides insight into the importance of tuning the interfacial toughness, current collector properties, stack pressure, and cell geometry to optimize performance and control plating uniformity. Informed by these insights, the areal Li coverage after 2 mAh/cm² of plating is increased from 50% to 95%. The understanding from this study informs future optimization of in situ anode formation in solid-state systems.

无阳极固态电池可以实现高能量密度和制造高质量界面的能力。然而，在原位阳极形成过程中，动态机械应力会影响初始的锂金属镀层形态。这项工作利用操作3D 视频显微镜来表征在石榴石 Li ₇ La ₃ Zr ₂ O _12上原位阳极形成过程中的电极形态(LLZO) 固体电解质。耦合的形态演化和电化学特征被识别并归因于界面处的应力变化。我们展示了应力对界面处热力学和动力学行为的影响。机械框架提供了对调整界面韧性、集流体特性、堆叠压力和电池几何形状以优化性能和控制电镀均匀性的重要性的洞察。根据这些见解，2 mAh/cm ²电镀后的面积锂覆盖率从 50% 增加到 95%。这项研究的理解为固态系统中原位阳极形成的未来优化提供了信息。