Reduced Drying Time of Anodes for Lithium-Ion Batteries through Simultaneous Multilayer Coating

Abstract

The extended process chain starting from slurry mixing up to the operative lithium-ion battery requires a deep understanding of each individual process step and knowledge of the interaction of the different process steps with each other. In particular, the intertwining of slurry mixing and drying determines the microstructure of the electrode, which in turn affects the performance of the cell. Herein, a scalable multilayer approach is used to tailor electrodes with improved mechanical and electrochemical properties, which disclose their advantages especially at high drying rates. Cryogenic broad ion beam scanning electron microscopy (Cryo-BIB-SEM) micrographs are used to reveal the influences of different process parameters, like slurry formulation, mixing device, and properties of the active material on the intrinsic network between active particles and binders in graphite-based anode slurries. By a chosen combination of these slurries in a multilayer electrode, a tenfold acceleration of the drying time with favorable mechanical and electrochemical properties for full cells derived from these anodes is demonstrated.