A Study on Selective Crushing and Physical Separation of Roasted Spent Lithium Ion Batteries

This study explored the crushing and physical separation technique as the pre-treatment of hydrometallurgical process for recovering valuable metals such as Co, Li, Ni and Cu from spent lithium-ion batteries (LIBs). Two types of LIBs, cylindrical one for personal computer and rectangular one for mobile phone, were roasted in the temperature range 673-873 K under a vacuum and were crushed by using single-axis cutter mill, hammer crusher, two-axis shear force crusher and high speed hammer mill. Then the crushed products were classified with screens and size distributions of the valuable metals were obtained. Selective crushing effects, that is, the degree of the difference in size distribution between several metallic elements, were evaluated in the fine and coarse particle size regions separately. Magnetic separation was carried out for the crushed product of the PC type LIB obtained under the most preferable conditions of the selective crushing. As the results, it was found that the combination of shear force crusher and high speed hammer mill was suitable for enhancing the selective crushing effect in both fine and coarse particle size regions, and this led to higher purity of the Co, Cu and Fe powders recovered after sieving and magnetic separation.