Process for recovering lithium and transition metals from waste cathode of spent lithium ion battery

A process for recovering lithium and transition metals, namely cobalt and nickel for spent NCM LIBs, from Black Mass powders physically separated from other parts and materials of used battery packs, comprising:

• I. partial reduction of Black Mass with added carbon in a reducing atmosphere facilitated by gas mixture of CO and CO2;
• II. separating residual carbon from other substances from partially reduced Black Mass using gravity separation;
• III. digestion of lithium carbonate and cobalt oxide in a cooled aqueous solution facilitated by CO2 injection and carbonate-bicarbonate ionic system;
• IV. filtering nickel oxide and manganese oxide from leachate solution containing soluble lithium and cobalt species
• V. complete reduction of nickel oxide with added carbon in a reducing atmosphere facilitated by gas mixture of CO and CO2
• VI. separating magnetic metallic nickel from non-magnetic tailing using wet magnetic separation;
• VII. precipitation of lithium carbonate and cobalt carbonate hydrate from the leachate solution via evaporative crystallization;
• VIII. calcination of precipitated crystal mixture to form cobalt oxide and lithium carbonate.