Leveraging Molecular Dynamics to Improve Porous Electrode Theory Modeling Predictions of Lithium-Ion Battery Cells

Abstract

Lithium-ion battery cell modeling using physics-based approaches such as porous electrode theory is a powerful tool for battery design and analysis. Cell metrics such as resistance and thermal performance can be quickly calculated in a pseudo-two-dimensional (P2D) framework. For engineering of electric vehicle batteries, speed and fidelity of electrochemical models is paramount in a competitive landscape. Physics-based models allow for high fidelity but require detailed knowledge of the cell component material properties. Acquiring these material characteristics typically requires time-consuming and expensive experiments limiting the ability to quickly screen through cell designs. One approach to circumvent costly experiments is to use molecular dynamics to calculate electrolyte transport properties. We demonstrate how cell modeling using simulated transport properties enables predictions of cell level metrics, allowing for experiment-free component screening. We also show how the variation in transport property predictions from molecular dynamics affects the final cell level performance predictions.

Application of the Multi-Species, Multi-Reaction Model to Coal-Derived Graphite for Lithium-Ion Batteries

“…Relevant equations governing Ohm's law in the solid phase, Ohm's law in the solution phase, charge conservation, and material Journal of The Electrochemical Society, 2024 171 023501 balances for the solid and solution phases are detailed in works by Lopata and colleagues, 60 Garrick and colleagues 61 and Dix and colleagues. 62 It should be noted that the system described in this work is a single porous electrode model, while those referenced above are dual and three porous electrode models respectively.…”

Reduced Order Electrochemical-Thermal Modeling of Cylindrical Cells Containing Graphite-Silicon Anodes Considering Thermal Gradients and Hysteresis

“…Full order model.-The fundamental governing equations, boundary conditions, and construction of the electrochemical model used in this study have been described in previous work. 42,43 In this continuum model approach, the mass transfer and the solid phase potential in the anode particles and the cathode particles are described by Fickian diffusion and Ohm's law, respectively. Mass transfer in the electrolyte phase is described by concentrated solution theory.…”

From Atoms to Wheels: The Role of Multi-Scale Modeling in the Future of Transportation Electrification

“…Researchers 25 have reported the benefit of classical MD to screen initial design matrices, allowing for the experimental characterization of only the most promising results. MD is also utilized to provide initial electrolyte properties and probe variation 26 in the inputs that are critical to robust VE, as reported from engineers at General Motors. While traditionally confined to academia, increases in computational power have reduced the simulation time from weeks to days, enabling wider impact through industry adoption.…”