摘要
提出了一种绿色的废旧电池LiFePO_4正极材料中温回收路线,并通过回收料中各种元素配比的控制和简单的热处理,实现了LiFePO_4正极的再生。从煅烧温度、煅烧时间及物料比三个方面优化了再生的工艺条件。通过X射线衍射谱(XRD)、扫描电镜(SEM)、透射电镜(TEM)和恒电流充放电进行了分析,结果表明高纯度球形LiFePO_4/C再生正极,在0.1 C率时的首次放电比容量为133.8 mAh/g,1 C下循环300次容量保持率达92.5%,性能接近商品化LiFePO_4材料。
We developed a green route to recycle LiFePO_4 from spent lithium-ion batteries at medium temperature,and regenerated LiFePO_4 cathode by controlling the elemental ratios in the recycled materials as well as subsequent simple heat treatment. The regeneration process was optimized by adjusting calcining temperature, calcining time and raw material ratios. The physical and chemical properties of regenerated cathode were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscope(TEM) and galvanostatic charge/discharge. The results show that highly pure spherical LiFePO_4/C delivers an initial discharge specific capacity of 133.8 mAh/g at 0.1 C, and retains 92.5% of its initial capacity at 1 C after 300 cycles. The electrochemical performance of regenerated spherical LiFePO_4/C is close to that of commercialized LiFePO_4 cathode materials.
引文
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