Gong Rui, Li Chenchen, Meng Qi, Dong Peng, Zhang Yingjie, Zhang Bao, Yan Jin, Li Yong
Faculty of Metallurgy and Energy Engineering, National and Local Joint Engineering Laboratory for Lithium-ion Batteries and Materials Preparation Technology, Key Laboratory of Advanced Battery Materials of Yunnan Province, Kunming University of Science and Technology, Kunming, 650093, China.
Faculty of Metallurgy and Energy Engineering, National and Local Joint Engineering Laboratory for Lithium-ion Batteries and Materials Preparation Technology, Key Laboratory of Advanced Battery Materials of Yunnan Province, Kunming University of Science and Technology, Kunming, 650093, China.
J Environ Manage. 2022 Oct 1;319:115740. doi: 10.1016/j.jenvman.2022.115740. Epub 2022 Jul 19.
A sustainable closed-loop method for recovering waste lithium iron phosphate batteries is developed in this paper. Li was selectively leached from cathode materials in a system of NaHSO and HO. Under the optimal conditions of leaching temperature of 65 °C, 1.1 times molar quantity NaHSO, 2 vol% HO, solid-liquid ratio of 100 g/L and leaching time of 15 min, the leaching efficiency of Li can reach 99.84%, while Fe is only 0.048%. Meanwhile, XRD, FTIR, XPS and TEM analysis were carried out to explore the conversion mechanism in the oxidation leaching process of the original raw and leaching products. Li in the filtrate was precipitated with NaCO and converted into LiCO. The precipitated salty wastewater can be converted into leaching agent for recycling by adding a certain amount of sulfuric acid. The recycled products are used to synthesize LiFePO materials, and regenerated LiFePO materials show good electrochemical properties. The discharge capacity displays 141.3 mAhg at 1C, with the capacity retention rate of 99.4% after 200 cycles. This study provides a sustainable closed-loop process for recycling and reuse of waste LiFePO batteries, which promotes resource conservation and environmental protection.
本文开发了一种用于回收废旧磷酸铁锂电池的可持续闭环方法。在NaHSO和H₂O体系中，从正极材料中选择性浸出锂。在浸出温度65℃、NaHSO摩尔量为1.1倍、H₂O₂体积分数为2%、固液比为100g/L、浸出时间为15min的最佳条件下，锂的浸出效率可达99.84%，而铁仅为0.048%。同时，进行了XRD、FTIR、XPS和TEM分析，以探究原原料和浸出产物氧化浸出过程中的转化机理。滤液中的锂用Na₂CO₃沉淀并转化为Li₂CO₃。通过加入一定量的硫酸，沉淀出的含盐废水可转化为浸出剂进行循环利用。回收产物用于合成LiFePO₄材料，再生的LiFePO₄材料表现出良好的电化学性能。在1C下放电容量为141.3mAh/g，200次循环后容量保持率为99.4%。本研究为废旧LiFePO₄电池的回收再利用提供了一种可持续的闭环工艺，促进了资源节约和环境保护。
