Rheological Studies of LiNi0.6Mn0.2Co0.2O2-Based Slurry for the Development of Energy Dense Li-Ion Applications

Abstract

The manufacturing of lithium-ion batteries (LIBs) cathodes typically employs poly (vinylidene fluoride), PVDF, as a binder. This work aims to demonstrate the impact of mixing procedures on rheological properties of battery slurry and the electrochemical performance of the coated cathode. Key factors like solid content, mixing speed, and duration significantly impact the slurry preparation for LiNi0.6Mn0.2Co0.2O2 (NMC 622), which in turn affects coating quality. The initial assessment of rheological and electrochemical data suggests a correlation between mixing parameters like shear viscosity, storage modulus (G′), loss modulus (G″), and the electrochemical performance of the coating. This correlation is further fortified by analyzing the coating’s physical appearance and investigating surface morphology, potentially bolster the correlation between rheological findings and electrochemical performance. The ideal electrode is fabricated using 1.5 wt% binder, is achieved with a slurry prepared with relatively high solid content at low mixing speed and mixing time, resulting in approximately 80% capacity retention after 1000 cycles at 1 C in a full cell configuration. This study lays a foundation for enhanced comprehension and optimization, benefits both researchers and industry professionals.