Silicon anode electrodes exhibit a large microstructure design space as several carbon additives are considered to improve its conductivity and thus electrochemical performance. Investigating each combination experimentally is time-consuming. In this work, microstructure scale modeling is used to discriminate between different carbon additives to accelerate electrode development [1]. Baseline spherical C45, single wall carbon nano tube (SWCNT, cf. Fig. 1), carbon nano rods (CNR), and mixed SWCNT-CNR are considered and their respective impact on connectivity, effective conductivity, specific surface area, pore size distributions, and effective diffusivity are calculated to provide design recommendations. To do so, microstructures are numerically generated using the NREL open-source Microstructure Analysis Toolbox (MATBOX) available to the battery community* [2].Additionally, the model is used to correlate material utilization and silicon particle size, in agreement with experimental data, to further guide the selection of silicon material.Lastly, the model is used to investigate the porosity specific surface area relationship in the low porosity range, for which the analytical expression 3ε/r (with ε the particle volume fraction and r the particle radius) is no longer valid due to the packing density limit, and revealed a non-monotonic correlation. Such result is very relevant for silicon anode development as one major hindrance to this chemistry is its limited calendar life due to SEI growth, for which the specific surface area is a key parameter. *Nanotube generation new feature will be released after article [1] publication. [1] F. L. E. Usseglio-Viretta, J. H. Kim, J. Preimesberger, N. Neale, P. Weddle, A. Verma, A. M. Colclasure, Guiding the Choice of Carbon Nanotubes Conductive Additives for Silicon Anode Electrode Through Microstructure Scale Analysis, in preparation[2] F. L. E. Usseglio-Viretta, P. Patel, E. Bernhardt, A. Mistry, P. P. Mukherjee, J. Allen, S. J. Cooper, J. Laurencin, K. Smith, MATBOX: An Open-source Microstructure Analysis Toolbox for microstructure generation, segmentation, characterization, visualization, correlation, and meshing, SoftwareX, 17 (2022) 100915. Figure 1
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