The necessity of a feasible process for the recycling of lithium-ion batteries is nowadays evident due to the significant demand for raw materials for battery production, but also due to legislative requirements to achieve certain recycling efficiency with sufficient quality of the products. Special conditions to achieve high lithium recovery and its use in new batteries represent a challenge for a commercial hydrometallurgical approach. In this work, an early selective recovery of lithium using oxalic acid as a leaching agent is investigated. The different solubility of transition metals oxalates in comparison to lithium oxalate was the main driving force to achieve selective separation in the leaching step. Nickel, cobalt, and manganese oxalates are insoluble and remained in the solid residue, while lithium oxalate was dissolved in the solution. Using a design of experiments to optimize the operation, optimal parameters were identified as 60 °C, 60 min, 0.6 M oxalic acid, resulting in 98.8% leaching yield for lithium, while less than 0.5 % of cobalt and nickel, and 1.5% of manganese were leached. This can significantly improve the lithium recovery in the current recycling processes. Moreover, aluminum was completely dissolved, which is a phenomenon not reported previously. It would constitute an advantage to the subsequent recycling operations.

由于对电池生产原材料的巨大需求，以及在产品质量足够的情况下实现一定的回收效率的立法要求，当今锂离子电池回收可行工艺的必要性显而易见。实现高锂回收率的特殊条件及其在新电池中的应用对商业湿法冶金方法提出了挑战。在这项工作中，研究了使用草酸作为浸出剂的锂的早期选择性回收。与草酸锂相比，过渡金属草酸盐的不同溶解度是在浸出步骤中实现选择性分离的主要驱动力。镍、钴和锰的草酸盐不溶并保留在固体残留物中，而草酸锂溶解在溶液中。使用实验设计来优化操作，确定最佳参数为 60 °C、60 分钟、0.6 M 草酸，锂的浸出率为 98.8%，而钴和镍的浸出率低于 0.5%，而钴和镍的浸出率为 1.5%锰被浸出。这可以显着提高当前回收过程中的锂回收率。此外，铝完全溶解，这是以前没有报道过的现象。这将对后续的回收操作构成优势。此外，铝完全溶解，这是以前没有报道过的现象。这将对后续的回收操作构成优势。此外，铝完全溶解，这是以前没有报道过的现象。这将对后续的回收操作构成优势。