Solvent-Based Sequential Separation Processes for Direct Recycling of Lithium-Ion Batteries

The recycling of end-of-life lithium-ion batteries and the direct reintegration of the reclaimed materials into the battery supply chain are increasingly recognized as pivotal steps toward fostering a sustainable battery ecosystem. In a typical recycling process, the spent cells are discharged and shredded, followed by electrolyte recovery and component separation to remove/reclaim components like plastics, pouch material, and steel casing. As a result, a feedstock of anode and cathode on their current collectors is generated. This feedstock contains the most valuable components in a lithium-ion cell, including black mass (e.g., active cathode materials and graphite), Cu foils, and Al foils. To reclaim active electrode materials with high purity for direct regeneration, separation of electrode materials from their current collector as well as of anodes from cathodes is necessary. Current techniques require a complex set of separation processes to produce clean streams of material, resulting in lower recovery rates and higher costs. In this talk, solvent-based separation processes will be discussed to sequentially separate both anode/cathode and electrode/current collectors to recover cathode films, Al foils, anode films, and Cu foils. By circumventing a complex set of separation processes, the sequential separation method alone could fulfill the goal of reclaiming higher-purity materials, making recycling more profitable. The designed solution does not damage the active cathode materials nor corrode the metal foils. In addition, this process enables low-temperature separation in a cost-effective solution, reducing energy consumption and processing costs. The discussion will shed light on how environmentally sustainable and cost-effective sequential separation processes pave the way for direct recycling.