Lithium-ion batteries (LIBs) are extensively used for power storage in most gadgets, electric vehicles (EV), and energy storage devices. Spent LIBs are an excellent source of metals, which can be recycled and reused in new batteries to reduce environmental impacts. Our current study reports bioleaching-mediated metal recovery from spent nickel-, manganese-, cobalt (NMC)-based LIBs at a high solid content, using an autotrophic bacterium Acidithiobacillus ferrooxidans. Inductively coupled plasma–optical emission spectrometry (ICP-OES) analysis showed recoveries of 90% Ni, 92% Mn, 82% Co, and 89% Li from spent LIBs in 72 h at a solid content of 100 g/L. The X-ray diffraction (XRD) and scanning electron microscopy–energy dispersive X-ray spectroscopy (SEM–EDX) analyses of the LIB powder before and after bioleaching confirmed that most of the metals leached out from the batteries. A high leaching efficiency was achieved by elevated concentrations of H₂SO₄ and ferric ion in the A. ferrooxidans culture as well as replenished bacterial culture for three cycles during the bioleaching. The bioleaching process reported here can be used to efficiently extract metals from spent EV batteries in an eco-friendly manner.

中文翻译：

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生物浸出作为一种环保的方法，可以以高纸浆密度从用过的基于NMC的锂离子电池中回收金属

锂离子电池（LIB）广泛用于大多数小工具，电动汽车（EV）和能量存储设备中的电能存储。废旧锂电池是极好的金属来源，可以将其回收再用在新电池中，以减少对环境的影响。我们当前的研究报道了使用自养细菌酸性铁氧体氧化亚铁从高镍含量的镍，锰，钴（NMC）废旧生物中生物浸出介导的金属回收。电感耦合等离子体发射光谱法（ICP-OES）分析显示，在72 h内，固含量为100 g / L的废旧LIB回收了90％的Ni，92％的Mn，82％的Co和89％的Li。生物浸出前后的LIB粉末的X射线衍射（XRD）和扫描电子显微镜–能量色散X射线光谱（SEM-EDX）分析证实，大多数金属从电池中浸出。在生物浸出过程中，通过在三氧化二铁农杆菌培养物中增加H ₂ SO ₄和三价铁离子的浓度以及在三个循环中补充细菌培养物，可以实现较高的浸出效率。此处报道的生物浸出工艺可用于以环保的方式从废旧EV电池中高效提取金属。