Mechanical behavior of electroplated mossy lithium at room temperature studied by flat punch indentation

We report the Young's modulus and deformation behavior of electroplated mossy lithium at room temperature investigated by flat punch indentation inside an argon-filled glovebox. The Young's modulus of the mossy lithium with a porosity of about 62.3% is measured to be about 2GPa, which is smaller than that (similar to 7.8GPa) of bulk lithium. Both the mossy and bulk lithium show clearly an indentation creep behavior. Despite its highly porous microstructure, the impression creep velocity of the mossy lithium is less than one-thirtieth of that of bulk lithium under the same stress. We proposed possible mechanisms for the significantly higher deformation and creep resistance of the mossy lithium over bulk lithium. These findings are key to developing mechanical suppression approaches to improve the cycling stability of lithium metal electrodes.