红土镍矿矿渣制备磷酸铁锂及其锂离子电池正极性能研究

Preparation of lithium iron phosphate from laterite nickel ore slag and study on the positive electrode performance of lithium-ion batteries

红土镍矿中具有丰富的金属资源,经过矿石冶炼提取镍金属后会产生大量的矿渣,不仅造成严重的环境污染,还浪费了大量的铁资源。针对以上问题,本工作探索了一条新的综合利用思路,用红土镍矿矿渣制备磷酸铁锂,实现金属资源高价值的回收利用。本工作表明,目前由红土镍矿矿渣制备的磷酸铁锂为纳米球状颗粒,X射线衍射及其精修结果也证明了该磷酸铁锂良好的结构组成。电化学结果表明该磷酸铁锂与商用磷酸铁锂的性能几乎一致,在1C下能释放148.5mAh·g^(-1)的比容量,循环500圈容量保持率高达98.5%。此外,利用弛豫时间分布解析红土镍矿矿渣制备的磷酸铁锂的电化学交流阻抗谱,表明该材料具有较好的动力学行为。综上所述,本工作提出了一条极具经济价值和应用价值的红土镍矿矿渣回收思路,为含铁资源更好的综合利用提供新的实验支持。

Laterite nickel ore contains abundant metal resources.After smelting and extracting nickel metal from the ore,a large amount of slag is generated,which not only causes serious environmental pollution but also wastes a large amount of iron resources.In response to the above issues,this work explores a new comprehensive utilization approach to prepare lithium iron phosphate from laterite nickel ore slag,achieving high-value recycling of metal resources.This work indicates that the lithium iron phosphate currently prepared from laterite nickel ore slag is a nanospherical particle,and X-ray diffraction and refinement results also prove that the lithium iron phosphate has a good structural composition.The electrochemical results show that the performance of this lithium iron phosphate is almost identical to that of commercial lithium iron phosphate,with a specific capacity of 148.5 mAh·g^(-1)released at 1C and a capacity retention rate of up to 98.5%after 500 cycles.In addition,the electrochemical impedance spectroscopy of lithium iron phosphate prepared from laterite nickel ore slag was analyzed using relaxation time distribution,indicating that the material has good kinetic behavior.In summary,this work proposes a highly economically and practically valuable approach for the recovery of laterite nickel ore slag,providing new experimental support for better comprehensive utilization of iron containing resources.