During operation of lithium-ion batteries, cells experience volume change due to mechanical and electrochemical phenomena. This volume change can be described in two main modes: reversible and irreversible. Irreversible volume change permanently affects cell performance, often lowering the maximum capacity of cells over time making them less effective in storing energy. Irreversible volume change can come from a few different sources such as gasification of the electrolyte, dendritic growth or plating of lithium metal, and SEI growth on the active material. These phenomena reduce the effectiveness of battery cells by removing working ions from the electrolyte and blocking intercalation sites of the active material.Quantifying this behavior experimentally can be drawn-out, as cells must be properly cycled thousands of times as they would be in consumer applications. In order to speed up this process and test many different cell designs, simulations that can quantify the irreversible volume change and resultant capacitive losses should be developed. The 3D microstructure-based modeling method developed by Lopata offers a strong framework for development of these simulations. Through a combination of experimental cycling data and electrochemical simulations, volume change from irreversible sources can be accurately represented at a microscale level and extrapolated into cell level response.In this work, discrete element simulations (DEM) have been developed to quantify local irreversible volume change. These DEM simulations utilize data from electrochemical simulations with an equivalent microstructure, which have been informed from experimental measurements at a cell level. This can be coupled with reversible volume expansions in the DEM framework to give a full picture of volume change at the electrode/electrolyte microscale. The irreversible volume change predicted by the DEM simulations is used to estimate capacitive losses in the cell overtime.References T. R. Garrick, Y. Zeng, J. B. Siegel, and V. R. Subramanian, J. Electrochem. Soc., 170, 113502 (2023).U. Janakiraman, T. R. Garrick, and M. E. Fortier, J. Electrochem. Soc., 167, 160552 (2020).T. R. Garrick, J. Gao, X. Yang, and B. J. Koch, J. Electrochem. Soc., 168, 010530 (2021).T. R. Garrick et al., J. Electrochem. Soc., 170, 060548 (2023).A. Paul et al., J. Electrochem. Soc., 171, 023501 (2024).M. Song, Y. Hu, S.-Y. Choe, and T. R. Garrick, J. Electrochem. Soc., 167, 120503 (2020).S. T. Dix, J. S. Lowe, M. R. Avei, and T. R. Garrick, J. Electrochem. Soc., 170, 083503 (2023).T. F. Fuller, M. Doyle, and J. Newman, Journal of the electrochemical society, 141, 1 (1994).M. Doyle, T. F. Fuller, and J. Newman, Journal of the Electrochemical society, 140, 1526 (1993).J. S. Lopata et al., J. Electrochem. Soc., 170, 020530 (2023).S. Pannala, H. Movahedi, T. R. Garrick, A. G. Stefanopoulou, and J. B. Siegel, J. Electrochem. Soc., 171, 010532.T. R. Garrick, Y. Miao, E. Macciomei, M. Fernandez, and J. W. Weidner, J. Electrochem. Soc., 170, 100513 (2023)
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