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Numerical simulations of heterogeneous structures like battery modules of electric vehicles are challenging due to the various length scales involved in it. Even with the latest computing technology, it is impossible to simulate the crash scene of the full vehicle resolving all length scales. Such hurdles have prevented manufacturers to understand the mechanical response of battery packs in vehicle crash scenarios. In this work, the problem of multiple length scales was solved using the RVE technique based on homogenization theory. An appropriate representative volume element was identified, and a 3D FE model was developed. Classical first-order boundary conditions were used in this research work. The RVE was subjected to several macroscopic deformations, and its response was obtained. The homogenized material properties were computed from the obtained responses, and a material model available in LS-Dyna's material library was selected and calibrated to describe the nonlinear multiaxial behavior of the homogenized battery module at the macroscale. For validation, the USABC Crush and Drop Tests were simulated for the detailed and homogenized battery modules. The main output of this research is a robust and computationally efficient tool enabling satisfactory integration of a battery pack model to the vehicle for crash simulations, eliminating the need to simulate micro details at macro length scales. This approach significantly reduced the computational cost. For example, for a Drop Test simulation, the homogenized model reduced the simulation time from 40 hours (detailed model) to about 3 minutes, while maintaining a high precision ( R 2 = 0.9871) in predicting the load-displacement response. The system level modeling will enable the stakeholders to perform efficient optimization and safety evaluation for full-scale crashworthiness of electric vehicles. [ABSTRACT FROM AUTHOR]

Li‐ion batteries are widely used in electric vehicles (EVs) propulsion. Therefore, ensuring their safety under mechanical abuse and accidental loads is a major challenge for the industry. To get a better understanding of the battery behavior in such cases, material calibration and computational modeling of the battery cells are essential. This paper aims to develop a universal homogenized model for an 18,650 cell that can predict cell behavior under both axial and lateral loading cases as well as three‐point bending. Previous homogenized models presented in the literature have covered one or two of these cases, but none have been validated in all these three major loading scenarios. To achieve this, precise shell casing and jellyroll material calibrations were performed. The features included in this universal model are (I) uncoupled calibration of axial and lateral properties for the cylindrical jellyroll from experiments performed in these two loading directions and employment of an anisotropic crushable foam model to simulate these features, (II) using Hill's anisotropic yield criteria and modified Mohr–Coulomb fracture criteria for the shell casing. The universal model developed here was able to predict the response of the cell in all lateral, axial, and bending loading scenarios. A comparison of this model with the previously developed isotropic models shows the special advantage of the new model in cases of axial loading and bending. However, for lateral compression cases, even the isotropic model provides a very close prediction. The experiments used for this study were all performed on fresh discharged cells under quasi‐static loading. [ABSTRACT FROM AUTHOR]