Recycling And Reuse Of Nickel Cobalt Metal In Waste Li-ion Batteries

With the rapid development of lithium-ion batteries,related products are becoming more and more common in people's lives,and their market share has repeatedly increased.However,due to the limited service life of lithium-ion batteries,the number of discarded lithium-ion batteries continues to increase.If it is not even disposed of,the arbitrary disposal of lithium ion batteries will seriously pollute the surrounding environment and waste its resources.In this paper,nickel cobalt and other metals are recovered by acid leaching,and the recovered nickel cobalt metals are used in the preparation of Ni/Co-MOF.In addition,the MOF material was oxidized or sulfurized to obtain the corresponding NiO/CoO spheres and NiS₂/CoS hollow spherical shells.When applied to the electrode materials of supercapacitors,it shows excellent electrochemical performance.In this paper,first,the solvothermal method and hydrothermal method are used to prepare MOF spherical structure,and the MOF hollow spherical shell structure is obtained by sintering and vulcanization.X-ray diffraction?XRD?,scanning electron microscopy?SEM?and Energy Dispersive Spectroscopy?EDX?were used to characterize the crystal structure,ingredient and surface morphology of the material.The electrochemical performance of the material's supercapacitor was tested and analyzed by Electrochemical Impedance Spectroscopy?EIS?,constant current charge discharge?GCD?,and cyclic voltammetry?CV?.Through the adjustment of preparation conditions,Ni/Co-MOF material can present a spherical structure with regular shape,stable size and uniform distribution;NiO/CoO materials appear as regular spherical particles on the surface;NiS₂/CoS materials are hollow spherical shells composed of fine particles.The supercapacitor electrochemical performance test results show that the first discharge capacity of Ni/Co-MOF material reaches 579F/g,and after 3000 cycles,the specific capacitance retention rate is 41%;the first discharge capacity of NiO/CoO material is 786.75F/g,and after 3000 cycles,its specific capacitance retention rate is 53%;the first discharge capacity of NiS₂/CoS material is as high as 1509.08F/g,and after 3000 cycles,the specific capacitance retention rate is 65%,which has good electrochemical performance of the supercapacitor.