Numerous end-of-life LiFePO₄ batteries will emerge soon due to their limited lifespan. High reagent cost and environmental pollution of hydrometallurgy are the main factors that prevent the economic recycling of spent LiFePO₄. In this paper, an environment-friendly physical method, that is, high-intensity magnetic separation (HIMS), was introduced for the first time to demonstrate its feasibility in preconcentrating the LiFePO₄ from spent LiFePO₄ batteries. Numerical simulation combined with laboratory experiments of two typical HIMS separators, namely high gradient magnetic separator (HGMS) and induced roll magnetic separator (IRMS), were conducted. Simulation analysis indicated that the separation performance was related to the magnetic field strength. In the HGMS experiments using − 0.21 mm electrode powder (after grinding) as feed, the concentrate grade and recovery of LiFePO₄ were 74.54% and 96.60%, respectively. By contrast, in the IRMS experiments using electrode pieces (after shredding) as feed, the concentrate grade and recovery of LiFePO₄ cathode pieces were 93.30% and 98.69%, respectively. Surface morphological analysis of electrode powder implied that superfine LiFePO₄ particles produced by grinding adhered to or were embedded in coarse graphite particles, which seriously deteriorated the separation performance. By contrast, electrode pieces were considerably larger size, and the generation of superfine LiFePO₄ particles can thus be avoided.

由于使用寿命有限，许多报废的 LiFePO _{4电池将很快出现。}湿法冶金的高试剂成本和环境污染是阻碍废LiFePO ₄经济回收利用的主要因素。本文首次介绍了一种环境友好的物理方法，即高强度磁选（HIMS），证明了其从废LiFePO _{4中预浓缩LiFePO 4的可行性。}电池。对高梯度磁选机（HGMS）和感应辊式磁选机（IRMS）两种典型的HIMS分离器进行了数值模拟和室内实验。仿真分析表明，分离性能与磁场强度有关。在使用-0.21 mm电极粉末（研磨后）作为原料的HGMS实验中，LiFePO ₄的精矿品位和回收率分别为74.54%和96.60%。相比之下，在使用电极片（切碎后）作为原料的IRMS实验中，LiFePO ₄正极片的精矿品位和回收率分别为93.30%和98.69%。电极粉末的表面形貌分析表明超细LiFePO ₄研磨产生的颗粒粘附或嵌入粗大的石墨颗粒中，严重降低了分离性能。相比之下，电极片的尺寸相当大，因此可以避免超细LiFePO _{4颗粒的产生。}