This study focuses on a countercurrent leaching process (CLP) for the dissolution of high-value metals from cathode active material of spent lithium-ion batteries (LIBs). Its main aim is to improve the effective utilization of acid during leaching and allow for the continuous operation of the entire CLP by adjusting the process parameters. The overall recovery of lithium (Li), cobalt (Co), nickel (Ni), and manganese (Mn) was 98%, 95%, 95%, and 92%, respectively; the acid utilization of the leaching process exceeded 95% under optimum conditions. The optimum conditions for first stage leaching were 70 g/L solid–liquid (S/L) ratio at 40°C for 30 minutes, and 2.0 M sulfuric acid, 100 g/L S/L ratio, 7 g/L starch, at 85°C for 120 minutes for second stage leaching. After five bouts of circulatory leaching, more than 98% Li, 95% Co, 95% Ni, and 92% Mn were leached under the same leaching conditions. Furthermore, we introduced the Avrami equation to describe metal leaching kinetics from spent LIBs, and determined that the second stage leaching process was controlled by the diffusion rate. In this way, Li, Ni, Co, and Mn can be recovered efficiently and the excess acid in the leachate can be reused in this hydrometallurgical process, potentially offering economic and environmental benefits.

这项研究集中在逆流浸出工艺（CLP）上，用于从废锂离子电池（LIB）的阴极活性材料中溶解高价值金属。它的主要目的是提高浸出过程中酸的有效利用，并通过调整工艺参数使整个CLP连续运行。锂（Li），钴（Co），镍（Ni）和锰（Mn）的总回收率分别为98％，95％，95％和92％。在最佳条件下，浸出过程的酸利用率超过95％。第一步浸出的最佳条件是在40°C下30分钟的固液比为70 g / L，在20℃下以100 g / LS / L的比例添加2.0 M硫酸，7 g / L的淀粉。 85℃120分钟进行第二阶段浸出。经过五次循环浸出后，锂含量超过98％，钴含量超过95％，镍含量超过95％，在相同的浸出条件下浸出了92％的Mn。此外，我们引入了Avrami方程来描述用过的LIB的金属浸出动力学，并确定第二阶段的浸出过程受扩散速率控制。以此方式，可以有效地回收Li，Ni，Co和Mn，并且沥出液中的过量酸可以在该湿法冶金过程中重复使用，从而可能带来经济和环境效益。