Slurry preparation is the process of creating the viscous that will be coated onto current collectors to form battery electrodes. For a typical lithium-ion battery cathode slurry, this involves mixing the powdered active material (e.g., NMC), conductive carbon additives, binder (like PVDF), and a solvent (like NMP) into a homogeneous paste. For anodes, it could be graphite, binder, etc. The quality of this slurry is critical: it needs to have the right rheology (flow properties) so it can be coated evenly, and the ingredients must be well dispersed to avoid agglomerates or uneven distribution (which ties to mixing homogeneity). Slurry prep often involves high-shear mixers, planetary mixers, ball mills, or ultrasonic dispersion, depending on the material. Order of addition matters too; typically, binder is dissolved in solvent first, then powders are added gradually. The slurry may be deaerated (vacuum degassed) to remove bubbles before coating.
NOVONIX, in its pilot line operations, pays a lot of attention to slurry preparation. They experiment with mixing speeds, durations, and sequences to optimize the slurry for new materials. For instance, if a material has a hydrophilic surface and they’re using aqueous binders, they’ll adjust accordingly, or if it’s a new binder, they may find it needs a different solvent amount to get the right viscosity. NOVONIX might measure slurry viscosity and tweak solid content to reach the ideal balance between coatability and desired electrode loading. They also consider slurry stability—some slurries might settle if not coated quickly, so they evaluate how long a slurry can sit. In a research context, if a client’s material isn’t performing as expected, NOVONIX could identify slurry issues (like poor dispersion of conductive carbon leading to bad performance) and fix them. By mastering slurry preparation, NOVONIX ensures that when they test a new electrode material, the results reflect the material’s true potential and not a processing flaw. Moreover, they generate know-how that informs scaling: a slurry recipe that works in the pilot line is a good starting point for a larger factory process, making NOVONIX’s role pivotal in moving from powder to electrode successfully.
