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Abstract Lithium (Li) dendrite formation in Li-metal batteries (LMBs) remains a key obstacle preventing LMBs from their widespread application. This study focuses on the role of the stress field in the Li electrodeposits formation and growth. Coupled electrochemical and mechanical phase-field model (PFM) is used to investigate electrodeposited Li evolution under different conditions. The PFM results, using both the anisotropic elastic properties of Li and the random delivery of Li-ions through the solid electrolyte interface, show a significant local stress development indicating a direct correlation between the stress field and the origin of the undesired Li filaments initiation.
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A phase field model to simulate crack initiation from pitting site in isotropic and anisotropic elastoplastic material
Abstract A multiphysics phase field framework for coupled electrochemical and elastoplastic behaviors is presented, where the evolution of complex solid-electrolyte is described by the variation of the phase field variable with time. The solid-electrolyte interface kinetics nonlinearly depends on the thermodynamic driving force and can be accelerated by mechanical straining according to the film rupture-dissolution mechanism. A number of examples in two- and three- dimensions are demonstrated based on the finite element-based MOOSE framework. The model successfully captures the pit-to-crack transition under simultaneous electrochemical and mechanical effects. The crack initiation and growth has been demonstrated to depend on a variety of materials properties. The coupled corrosion and crystal plasticity framework also predict the crack initiation away from the perpendicular to the loading direction.
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- PAR ID:
- 10412595
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Modelling and Simulation in Materials Science and Engineering
- Volume:
- 31
- Issue:
- 5
- ISSN:
- 0965-0393
- Page Range / eLocation ID:
- Article No. 055002
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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