Vacuum-Drying of the LiNi1/3Co1/3Mn1/3O2 Cathode Material

Moisture greatly affects the performance of Li-ion batteries, so LiNi1/3Co1/3Mn1/3O2 (NCM111) powder is usually dried in vacuum before the slurry preparation. In this paper, vacuum-drying experiments of NCM111 powder were performed first and the effects of different conditions were investigated. Then, the experimental data were fitted to nine mathematical models, and the Weibull model was the best one to describe the drying kinetics. The relationship between model parameters and drying conditions was established and verified. Moreover, effective diffusivities were determined using the Fick's equation and the activation energy was calculated using the Arrhenius equation. The energy consumption was also discussed in the end. The result shows that increasing drying temperature can not only improve drying performance but also reduce energy consumption. However, reducing thickness of NCM111 powder is beneficial to elevate the drying rate but has little effect on saving energy.