Drying of lithium-ion battery negative electrode coating: Estimation of transport parameters

Drying of the coated slurry using N-Methyl-2-Pyrrolidone as the solvent during the fabrication process of the negative electrode of a lithium-ion battery was studied in this work. Three different drying temperatures, i.e., 70˚C, 80˚C and 90˚C were considered. The drying experiments were carried out in a laboratory tray dryer at atmospheric pressure. Mass transfer coefficient and effective capillary diffusivity of the solvent during drying were estimated. A semi-empirical model was developed to estimate the parameters. In addition, different thin-layer empirical models were fitted to the experimental data, and the parameters were estimated using the best-fitted model. During the drying process, shrinking of the coating was considered while estimating the parameters.