(Invited) Circular Manufacturing of Next-Generation Lithium-ion Battery Cathode Materials with R2R Molten Salt Electrodeposition

Abstract

For the past few years, Xerion has been developing a roll-to-roll (R2R) molten salt electrodeposition technology (DirectPlateTM) for circular manufacturing of lithium-ion battery cathodes. Cathode materials such as LiCoO2, Li(NixMyCoz)O2, and LixMnyOz are demonstrated with good electrochemical properties. DirectPlateTM cathodes are distinctly different from conventional slurry-cast electrodes combining several notable properties: they are very dense with less than 10% porosity, free of additives (carbon and polymer binder), and their crystal orientation can be accurately controlled, enabling high-rate operation at or beyond state-of-the-art areal capacity loading (3-4 mAh/cm2). As Li+ diffusion primarily occurs through the single crystalline domains aligned vertically to the current collector, DirectPlateTM LiCoO2 cathodes delivers good electrochemical properties in a solid-state cell without the need to infiltrate electrolyte into the cathode. We further demonstrate that end-of-life DirectPlateTM cathodes can be efficiently re-lithiated and repaired with a short molten salt treatment; or they can be upcycled into another cathode material with a completely different composition. Finally, we demonstrate that the DirectPlateTM cathode can be employed as a redox membrane for direct lithium extraction from various lithium-containing solutions. Integrating the collective mineral refinement, electrode fabrication and recycling capabilities into the R2R DirectPlateTM platform enables next-generation circular battery manufacturing with much lower energy and environmental cost.