Development of an Induction Supported Roll to Roll Process for the Accelerated Drying of Water-Based Anodes and N-Methyl-2-Pyrrolidone-Based Cathodes for Lithium-Ion Batteries

Abstract

The electrode drying process in lithium-ion-battery production is energy-intensive and contributes significantly to production costs due to its large machine footprint. This study explores the use of induction heating technology to enhance drying rates and overall process efficiency compared to traditional convective drying methods. A novel monitoring method utilizing spot temperature measurements with infrared pyrometers is developed to assess drying dynamics effectively in a pilot-scale roll-to-roll dryer. Results show a mean drying rate increase of 23.0% for water-based anodes and 13.4% for N-methyl-2-pyrrolidone-based cathodes, with an inductive heating efficiency of up to 60%. Additionally, electrodes treated at moderate induction intensities maintained mechanical properties and electrochemical performance comparable to conventionally dried electrodes. To address overheating risks in uncoated foil areas, effective shielding solutions are implemented, reducing oxidation and thermal degradation from inductive heating. The success of induction heating in this pilot-scale environment raises its technology readiness level (TRL) to TRL5 as it closely resembles realistic production environments, indicating its relevance for realistic production scenarios. This research offers important insights into the application of induction heating for lithium-ion-battery electrode production and highlights potential areas for further optimization and scalability.