LI-ION BATTERY RECYCLING AT PILOT SCALE: DEMONSTRATING THE RESYNTHESIS ROUTE ALSO FOR NMC-LFP MIXED BLACK MASS

The hydrometallurgical recycling of end-of-life Li-ion batteries constitutes a sustainable path for the integral recovery of battery components. However, the heterogeneity of electrode materials constitutes a limitation for process optimization that must provide robust and flexible strategies. In this work, the preliminary results obtained as part of the demonstration activities of the LIFE DRONE project are reported with particular attention to the possibility of integrating the recycling process based on the resynthesis of NMC (Nickel Manganese Cobalt) cathodes with the treatment of mixed black mass also containing LFP (Lithium Ferrous Phosphate) electrodic powders. The experimental results obtained highlight the possibility of leaching NMC black mass in the absence of hydrogen peroxide when NMC-LFP mixtures are used with almost quantitative extraction yields of metals. In particular, working without H2O2 at 60°C for 3 h the following yields of extraction were obtained: 89% for Ni, 69% for Mn, 89% for Co, 91% for Li, 90% for Fe, 100% for P, 56% for Al and 32% for Cu. Furthermore, the experimental data showed that by varying the pH of the leach liquor, it is possible to separate selectively iron phosphate by quantitative precipitation (100% for Fe, 100% for P and 60% for Al) before proceeding with NMC resynthesis.