In-line Visualization of Particle Dispersion Configuration in Cathode Slurry Mixing by Electrical Equivalent Circuit-Electrical Impedance Tomography (EEC-EIT); 電気等価回路インピーダンストモグラフィ(EEC-EIT)による正極スラリー混合中のスラリー内部構造のインライン可視化

Particle dispersion configuration in LiCoO2-CB-NMP/PVDF cathode slurry of lithium-ion battery (LIB cathode slurry) has been cross-sectionally visualized by Electrical Equivalent Circuit- Electrical Impedance Tomography (EEC-EIT). EEC-EIT reconstructs two types of conductivity images regarding LiCoO2 particle interface ΔσPI and NMP-PVDF solution ΔσSO from the resistance elements RPI and RSO calculated by EEC model, which is modeled based on the configuration of LIB cathode slurry. We experimentally evaluated EEC-EIT under LIB cathode slurry mixing in a beaker with eight electrodes at mixing speed of ω = 200 rpm or 700 rpm. As the results, ΔσPI and ΔσSO were increased as the mixing time t elapses, which indicates that CB particles penetrated between LiCoO2 particles and that formation of CB-PVDF aggregates occurred, respectively. Moreover, the two types of images are quantitativity compared with scanning electron microscope (SEM) images. © 2024 Society of Powder Technology. All rights reserved.