Abstract
Mechanical suppression, e.g., by applying stack pressures and using functionalized coatings, has been considered a promising approach to inhibit the formation of lithium (Li) dendrites and improve the cycling stability of the Li metal electrode. However, a lack of understanding of the mechanical behavior of electroplated mossy Li, consisting of loosely packed Li dendrites that are covered by solid electrolyte interphase, hinders the development of mechanical suppression strategies and limits the understanding of the electromechanical behavior of mossy Li. In this study, we investigated, using flat punch indentation in an argon-filled glovebox, the room temperature mechanical behavior and its relationship with the microstructure of mossy Li electroplated using different current densities (between 0.25 and 10 mA/cm2) in several electrolytes. The dendrite size decreases and the porosity of mossy Li increases with increasing current density. Mossy Li has lower Young's modulus (E) but significantly higher creep resistance than bulk Li. A scaling relationship between E and porosity is established for mossy Li. The creep behavior of mossy Li exhibits a strong size effect, i.e., the steady-state impression velocity decreases with decreasing dendrite size. These findings provide a comprehensive understanding of the relationship between the microstructure and mechanical behavior of mossy Li.
Original language | English |
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Pages (from-to) | 276-282 |
Number of pages | 7 |
Journal | Energy Storage Materials |
Volume | 26 |
DOIs | |
State | Published - Apr 2020 |
Bibliographical note
Publisher Copyright:© 2020 Elsevier B.V.
Keywords
- Creep
- Lithium metal electrode
- Mechanical behavior
- Porosity
- Size effect
ASJC Scopus subject areas
- Renewable Energy, Sustainability and the Environment
- General Materials Science
- Energy Engineering and Power Technology