Closed-loop hydrometallurgical treatment of end-of-life lithium ion batteries: Towards zero-waste process and metal recycling in advanced batteries

This work presents an enhanced hydrometallurgical process for recycling lithium ion batteries. First, end-of-life batteries were processed in a physical pre-treatment plant to obtain a representative electrode material. The resulting leachate was purified forth by iron-precipitation, liquid-liquid extractions, and an innovative Li-Na separation, in order to obtain valuable products. These products include high-grade graphite, cobalt oxide (Co3O4, purity 83%), cobalt oxalate (CoC2O4, purity 96%), nickel oxide (NiO, purity 89%), and lithium carbonate (Li2CO3, purity 99.8%). The recovery rate was quantitative for graphite, between 80% and 85% for cobalt depending on the nature of the recovery method, 90% for nickel, and 72% for lithium. Secondary streams were also valorized to obtain sodium sulfate (Na2SO4, purity 96%), and MnCoFe2O4 magnetic nano-sorbents according to the zero-waste concept. In order to close the loop, recycled Co3O4 and NiO were used as conversion-type anode materials for advanced lithium ion batteries showing promising performances. (C) 2019 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.