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Abstract The dynamic behavior of the interface between the lithium metal electrode and a solid-state electrolyte plays a critical role in all-solid-state battery performance. The evolution of this interface throughout cycling involves multiscale mechanical and chemical heterogeneity at the micro- and nano-scale. These features are dependent on operating conditions such as current density and stack pressure. Here we report the coupling of operando acoustic transmission measurements with nuclear magnetic resonance spectroscopy and magnetic resonance imaging to correlate changes in interfacial mechanics (such as contact loss and crack formation) with the growth of lithium microstructures during cell cycling. Together, the techniques reveal the chemo-mechanical behavior that governs lithium metal and Li 7 La 3 Zr 2 O 12 interfacial dynamics at various stack pressure regimes and with voltage polarization.
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Electro-Chemo-Mechanical Properties of 2D Materials for Energy Storage: Computational Frontiers
Abstract Two-dimensional materials (2DM) and their heterostructures (2D + nD, where n = 0, 1, 2, 3) hold significant promise for electrochemical energy storage systems (EESS), such as batteries. 2DM can act as van der Waals (vdW) slick interfaces between conventional active materials (e.g., silicon) and current collectors, enhancing interfacial adhesion and mitigating stress-induced fractures. They can also serve as alternatives to traditional polymer binders (e.g., MXenes), highlighting the importance of interfacial mechanics between 2DM and active materials. During charge/discharge cycles, intercalation and deintercalation processes substantially affect the mechanical behavior of 2DM used as binders, collectors, or electrodes. For example, porous graphene networks have demonstrated capacities up to five times greater than traditional graphite anodes. However, modeling 2DM in EESS remains challenging due to the complex coupling between electrochemistry and mechanics. Defective graphene, for instance, promotes strong adatom adsorption (e.g., Li⁺), which can hinder desorption during discharge, thereby influencing mechanical properties. Despite the promise of 2DM, most current studies fall short in capturing these critical chemo-mechanical interactions. This perspective provides a comprehensive overview of recent advances in understanding the mechanical behavior of 2DM in EESS. It identifies key modeling challenges and outlines future research directions. Multiscale modeling approaches—including atomistic and molecular simulations, continuum mechanics, machine learning, and generative artificial intelligence—are discussed. This work aims to inspire deeper exploration of the chemo-mechanics of 2DM and offer valuable guidance for experimental design and optimization of 2DM-based EESS for practical applications.
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- Award ID(s):
- 2237990
- PAR ID:
- 10629959
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Journal of the Indian Institute of Science
- ISSN:
- 0970-4140
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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