Unveiling heterogeneous deformation in lithium batteries through operando Von Mises stress analysis and in situ Digital Volume Correlation
par Quentin MOGLIA, Christophe CARRAL,Nicolas LENOIR, Olga STAMATI, Pierre-Xavier THIVEL
Journal of Energy Storage , https://doi.org/10.1016/j.est.2026.123888
Lithium-ion batteries (LIBs) are widely used in modern energy storage application. However, their mechanical degradation remains a major challenge for reliability and safety. This study introduces a new experimental methodology combining operando measurements using strain gauge rectangular rosettes and stepwise in situ X-ray micro-computed tomography (X-ray CT) coupled with Digital Volume Correlation (DVC) to quantify the spatially resolved mechanical response of 18650 cylindrical cells during charging. Strategically positioned strain gauges around the cell casing are correlated with three-dimensional kinematic fields obtained from DVC, revealing highly heterogeneous strain distributions and significant Von Mises stress concentrations (50–125 MPa) associated with the winding jelly-roll architecture and electrode lithiation. Moreover, the results highlight the so-called ‘Potato Effect’, a strongly heterogeneous deformation mode characterized by alternating regions of expansion and contraction. This behavior arises from the coupled effects of electrode swelling and retracting, current collector tab positioning, and the mechanical constraint imposed by the casing. By linking surface local strain measurements with global 3D deformation fields, this work provides new insights into electro-chemo-mechanical coupling in LIBs and establishes a robust framework for identifying critical mechanical heterogeneities that may drive fatigue and long-term degradation.
Lithium-ion batteries (LIBs) are widely used in modern energy storage application. However, their mechanical degradation remains a major challenge for reliability and safety. This study introduces a new experimental methodology combining operando measurements using strain gauge rectangular rosettes and stepwise in situ X-ray micro-computed tomography (X-ray CT) coupled with Digital Volume Correlation (DVC) to quantify the spatially resolved mechanical response of 18650 cylindrical cells during charging. Strategically positioned strain gauges around the cell casing are correlated with three-dimensional kinematic fields obtained from DVC, revealing highly heterogeneous strain distributions and significant Von Mises stress concentrations (50–125 MPa) associated with the winding jelly-roll architecture and electrode lithiation. Moreover, the results highlight the so-called ‘Potato Effect’, a strongly heterogeneous deformation mode characterized by alternating regions of expansion and contraction. This behavior arises from the coupled effects of electrode swelling and retracting, current collector tab positioning, and the mechanical constraint imposed by the casing. By linking surface local strain measurements with global 3D deformation fields, this work provides new insights into electro-chemo-mechanical coupling in LIBs and establishes a robust framework for identifying critical mechanical heterogeneities that may drive fatigue and long-term degradation.