The effect of chelating agent on synthesis and electrochemical properties of LiNi0.6Co0.2Mn0.2O2

Ni-rich cathode material is one of the most promising material for Li-ion batteries (LIBs) in portable power and electric vehicles. However, how to recycle waste LIBs cathode materials is very important for environmental protection and resource utilization. LiNi0.6Co0.2Mn0.2O2 cathode materials were prepared by sol-gel combustion method Using waste LIBs cathode materials as raw materials. The effect of different gels on the crystal structure and morphology of LiNi0.6Co0.2Mn0.2O2 were studied by X-ray diffraction and scanning electron macroscopy. The electrochemical properties were investigated by charge-discharge testing, cyclic voltammetry and electrochemical impedance spectroscopy. The results showed that the samples contained some residual C and primary crystals have been formed during combustion stage. When glucose was used as gel regent, the sample has the good electrochemical properties with the initial discharge capacity of 176.9 mAh g(-1), initial coulombic efficiency of 87.0% and discharge capacity retention rate of 95.8% after 50 cycles at 0.2 C rate. The results showed that the less the cation mixing, the more complete of hexagonal crystal structure, which induced the decrease of impedance resistance and good reversibility of redox reaction.