2, Mechanical and Aerospace Engineering, University of Central Florida, Orlando, Florida, United States
Lithium metal is known as the “Holy Grail” of anode materials, as it has the highest theoretical capacity, lowest density, and most negative electrochemical potential of known anode materials for rechargeable batteries. Unfortunately, dendrites of lithium form during repeated cycling, posing a safety hazard and deterring commercialization of lithium metal batteries. Previous studies, each with different methods of sample preparation and testing methods, show that Lithium’s yield strength may vary by more than 2 orders of magnitude (from ~1 MPa to 100-300 MPa). However, comprehensive knowledge of the mechanical behavior of Li remains a key obstacle to understanding how to engineer anode-separator interfaces that can mitigate or suppress dendrites. Through a combination of in-glovebox tensile testing and nanoindentation in as-received lithium ribbon, we probe the mechanical properties of Li metal at different length scales.