Liberation of Cathode Active Materials by Grinding Process for Direct Recycling of Waste Materials from Lithium Ion Battery Manufacturing Process

In this study, promotion of liberation and recovering of cathode active materials by the grinding process were investigated for a scrap sample simulating cathode slurry in lithium ion battery manufacturing process. In the grinding process, we tried to minimize the percentage of cracked cathode active materials and to maximize the weight ratio under 32 μm. During the grinding by a jaw crusher with a gap size 0.5 mm, it was confirmed that the cathode materials were volumetrically ground without as cracking cathode active materials as possible. The sample was then ground by the attritor with different size of grinding media (φ3 and φ10), and we found that the ground material was superficially ground without as cracking cathode active materials as possible in the case of using single grinding media size (φ10). Our results show that the combination of volumetric grinding and surface grinding can effectively promote the liberation state of cathode active materials without cracking.