Research on the regulation of lithium-ion battery electrode coating stability

The electrode slot die coating for lithium-ion batteries is characterized by its large scale and high efficiency, with significant advancements in recent years. Coating stability, a critical factor of lithium-ion batteries quality, is significantly influenced by numerous factors. To address this, a computational model for slot die coating has been developed to ensure stable electrode coatings. The model examines the impact of slurry speed at the slot exit (Vslurry) and substrate movement speed (V) on both coating stability and coating thickness (h), aiming to create a prediction model. The electrode coating state is classified into three distinct categories: fluid weeping, stable coating, and bead breakup, based on the meniscus position of the coating. By effectively managing the process parameters, this prediction model can mitigate defects during the coating, facilitating efficient, and stable electrode coatings. Moreover, the model enables adjustments to coating thickness at different coating speeds. Specifically, when the Vslurry ranges from 0.250 and 0.750 m/s, the corresponding stable V spans 0.255–1.800 m/s, with h varying from 0.200 to 0.480 mm under these conditions. This study provides theoretical guidance for regulating the stability of slot die coating in lithium-ion battery electrodes and establishes a theoretical foundation for the selecting optimal process parameters in practical applications, which holds considerable significance.