Method for producing secondary battery material from black mass

A method for producing a secondary battery material from black mass, comprising:

• roasting black mass to produce roasted black mass;
• leaching the roasted black mass with water to separate a first lithium (Li) solution and a cake;
• producing lithium carbonate (Li2CO3) crystals by evaporating and concentrating the first lithium (Li) solution;
• leaching the cake separated from the first lithium (Li) solution;
• removing copper and aluminum from a leaching solution produced by the leaching of the cake, which includes removing of the copper by adding sodium hydrogen sulfide (NaHS) to the leaching solution and removing the aluminum by adding sodium hydroxide (NaOH) to the leaching solution;
• neutralizing the leaching solution and separating the leaching solution into a second lithium (Li) solution and a cake containing Ni, Co, and Mn (“NCM cake”);
• and
• feeding the lithium carbonate (Li2CO3) crystals and the second lithium (Li) solution produced by the separating of the leaching solution to a lithium hydroxide (LiOH) production process, which includes:
• producing a lithium phosphate (Li3PO4) cake by adding phosphoric acid (H3PO4) and sodium hydroxide (NaOH) to the second lithium (Li) solution produced by the separating of the leaching solution,
• preparing a lithium sulfate (Li2SO4) solution by co-leaching the lithium carbonate (Li2CO3) crystals and the lithium phosphate (Li3PO4) cake together with sulfuric acid,
• precipitating lithium carbonate (Li2CO3) by adding sodium carbonate (Na2CO3) to the lithium sulfate (Li2SO4) solution,
• preparing a lithium hydroxide (LiOH) solution by adding calcium oxide (CaO) and water to the lithium carbonate (Li2CO3), and
• evaporating and concentrating the lithium hydroxide (LiOH) solution.