Mechanical Properties and Deformation Behavior of Lithium Metal

Lithium metal is the ideal candidate as anode material for reaching higher energy densities. However, comprehensive and reliable research on its complex mechanical deformation remains scarce, hindering an in-depth understanding of Li-based solid-state batteries. Lithium mechanical properties vary widely depending on length scale, orientation, strain rate and temperature. Besides, lithium is extremely reactive, creeps at room temperature and has a strong anisotropy, making experimental characterization a considerable challenge. This work aims to study the mechanical properties and deformation of lithium using a combination of experimental and modeling tools. On the theoretical side, techniques such as first-principles, molecular dynamics and effective medium theory are applied. Information not only from the elastic parameters, but also from the plastic regime is obtained. Simulations are carried out for different temperatures, specimen sizes and crystal orientations. On the experimental side, micro-indentation is performed and the hardness of lithium foils is evaluated. With this study, we expect to support investigations regarding the size and orientation dependency of Li mechanical properties. Additionally, we aim to contribute to bridging the gap between theory and experiments, as well as understanding plasticity on small scales, high strain rates and high homologous temperatures.