Operando Infrared Thermography and Quantitative Insights into Lithium Plating Dynamics on Electrodes during Fast Charging

Abstract

Lithium-ion batteries (LIBs) are critical to enabling electric vehicles and grid storage due to their high energy density and longevity. However, the development of extreme fast-charging (XFC) protocols is challenged by non-uniform thermal behavior that promotes lithium plating—a key degradation mechanism compromising safety and cycle life. This work presents an integrated approach combining operando infrared (IR) thermography and validated physics-based modeling to quantify spatial temperature gradients and their influence on lithium plating in custom-designed graphite | Li half-cells during high-rate charging. Geometry-driven current localization causes thermal hotspots and localized Li plating via electro-thermal coupling. This study provides mechanistic insight into how geometry-driven current localization couples with temperature gradients to bias where plating nucleates and grows in an operando half-cell. While the absolute plating severity in commercial full cells can differ, the framework identifies electro-thermal localization mechanisms that are relevant for understanding and designing cell hardware and charge protocols to reduce plating risk. The combined experimental-modeling framework advances understanding of plating heterogeneity and provides a pathway for optimizing cell design and charging protocols to enable safe, high-power LIB operation.