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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.

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In this paper, a full mandibular CT-scan in a specific patient is used to model BSSO surgery. The purpose is to compare the three most common fixation methods which are used in BSSO surgery by finite element method. Three different fixations are studied in order to obtain the minimum displacement of the lower jaw and optimum stress and strain on the specified fixation. The methods are two parallel plates with four screws, the operation of triangular screw configuration and one plate with four screws. The plates and the screw are modeled precisely by point clouds of Synthes Brand’s plate and screw. The mechanical properties of the full mandibular and, to obtain a practical model after the surgery, the mean jaw forces are extracted from literatures. It is resulted that the minimum displacement and stresses on the mandible and fixation tools happened in the Triangular screw configuration model and the two other methods have higher stress and lower displacement. Therefore, the mandibular in triangular method, experiences little deformation and the screws tolerates lower stress and strain which is better than the other two methods.

Mechanical abusive loadings, as an inevitable consequence of road accidents, can damage the embedded energy storage system in an electric vehicle and deform its constitutive parts e.g., the lithium-ion batteries. Therefore, to study the mechanical responses of these batteries and avoid expensive testing equipment and rigorous safety percussions, researchers are propelled toward utilizing numerical models. Computationally cost-efficient homogenized finite element models that represent the whole battery in form of a uniform medium, are the most feasible solution, especially in large-scale battery stacks simulations. Compared to the other form factors of the batteries, prismatic cells have been understudied even though they have higher packaging efficiency, by making optimal use of space. In this paper, a comprehensive homogenization and failure calibration method was developed for these prismatic cells. The homogenization was done through extensive uniaxial components tests of the jellyroll and the shell casing. In addition, biaxial tensile tests and simulations were used to calibrate strain-based failure criteria for the components. The calibrated homogenized model is validated in various punch loading scenarios and used in the characterization of the load-displacement responses and failure modes of the stacked cells configurations. In the stacked simulations, due to the cushion-like behavior of the other cells, the failure happens in higher values of displacement compared to a single cell. However, the normalized intrusion percentages for the battery stacks are lower compared to a single battery cell. This emphasizes the importance of the safety assessment of an electric vehicle based on the failure analysis of the battery stacks rather than a single cell. This goal would be feasible through simulations of only homogenized cell models in the stacked configurations which are elaborated in this paper for prismatic cells.

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