Regeneration of Cathode Mixture Active Materials Obtained from Recycled Lithium Ion Batteries 2020-01-0864
The recycling of rechargeable Lithium-ion batteries (LIBs) has attracted more attention in the past few years due to its tremendous advantages to the economy and environment. However, none of the currently developed recycling processes are completely economical for all types of LIBs. If the electrode active materials of spent LIBs can be effectively separated and directly regenerated to build new LIBs, the LIBs’ recycling process may become economical. Since all types of LIBs are usually recycled at the same time without sorting them considering the types of electrodes and manufacturers, the separation of electrodes materials in the filter cake, as the product of the recycling facilities becomes crucial. In this paper, we show that the anode and cathode mixture materials in the filter cake can be easily and effectively separated, and the resulted cathode mixture materials can be directly regenerated to be used to build new LIBs with multiple intercalating cathode materials. The proposed process starts with separating the cathode mixture and anode materials by adopting Stokes’ law for mineral separation; then, the separated cathode mixture is regenerated through a process involving heat treatment and lithiation. The experimental results confirm that (a) the complete and rapid separation of the anode and cathode mixture materials from each other are possible, (b) the cathode mixture can be regenerated, and (c) the capacity of the half-cells built from both regenerated cathode mixture and fresh cathode mixture materials are relatively close to each other. This research is continuing to evaluate the cycling and calendar life of the regenerated cathode mixture as well as the performance of the blended and fresh cathode mixture materials.