Modeling of Micro-deformations Due to Global Loads of a Cylindrical Lithium-ion Cell

This study presents a framework for modeling and predicting micro-deformation and mechanical deformation mechanisms in cylindrical lithium-ion batteries. The proposed method delivers the first full-cell model that explicitly represents all layers of the spiral jellyroll and all end-cap components, enabling detailed analysis of micro-deformations and interactions among cell components. The minimum required experiments, material calibrations, and validation procedures are systematically defined for each component. The model is validated against five mechanical abuse scenarios relevant to battery safety: radial compression, axial compression, three-point bending, hemispherical punch indentation, and rod indentation. Quantitative comparisons with experiments demonstrate strong agreement, with coefficients of determination (R² ≥ 0.93) in all loading scenarios and peak force deviations up to 8.8%. Beyond reproducing global load–displacement responses, the model captures internal deformation mechanisms and identifies key phenomena governing each loading condition. Under radial compression, deformation is dominated by collapse of the central cavity and buckling of endcap components such as the CID and top cover. Axial loading is governed by closure of the crimped endcap region followed by casing buckling, along with compression of internal components including the gasket, CID, and insulator. Local indentation responses are primarily controlled by compression of electrode coatings, while three-point bending highlights the role of interlayer adhesion and sliding. This step-by-step framework provides a high-fidelity tool for cell engineering, component design, and mechanical response evaluation, while enabling design optimization and safety assessment through explicit links between material properties, geometry, and global cell behavior.