废旧三元锂离子电池正极有价金属的回收工艺研究

随着电动汽车和大规模储能市场的快速发展,锂离子电池的销量快速增长,随之产生的废旧锂离子电池数量也日益增长。其中,三元正极锂离子电池含有锂、镍、钴、锰等有价金属,具有较高的回收价值。本文以废旧三元锂离子电池正极片为原料,采用高温热处理法去除正极中的粘结剂和导电碳,以提高有价金属在酸液浸出的回收率。重点考察了高温热处理的温度和时间对有价金属酸浸出率的影响。结果表明:当三元正极热处理温度为650℃、时间为120 min时,正极中粘结剂和导电碳分解完全;在酸浸实验中,在硫酸浓度为4 mol/L,H₂O₂体积含量为11.1%、固液比为55.5g/L、反应温度为80℃、反应时间为2 h条件下,锂、镍、钴、锰的浸出率分别达到99.5%、98.9%、98.7%、98.7%。

Study on Recovery Process of Valuable Metals of Ternary Cathode in Spent Lithium-Ion Battery

In recent years, with the rapid development of electric vehicles and large-scale energy storage market, the sales of lithium-ion batteries are also growing rapidly, and the number of spent lithium-ion batteries is also growing. Among them, the ternary cathode of lithium-ion battery contains valuable metals such as lithium, nickel, cobalt, manganese, which has high recovery value. In this paper, the binder and conductive carbon in spent ternary cathode were removed by high temperature heat treatment to improve the recovery of valuable metals in acid leaching. The effect of temperature and time of high temperature heat treatment on acid leaching rate of valuable metals was investigated. The experimental results showed that the binder and conductive carbon decomposed completely when the heat treatment temperature of the ternary cathode of lithium battery was 650^oC and the time was 120 min. Under the optimal leaching conditions of 4 mol/L H₂SO₄, 11.1vol.% H₂O₂, a solid-liquid ratio of 55.5g/L at 80^oC for 2 hours, the leaching rate of lithium, nickel, cobalt and manganese were 99.5%, 98.9%, 98.7% and 98.7%, respectively.