Electrochemical properties of ZnO anode materials with MicNo® morphology

ZnO-based anodes are currently possessing drawbacks such as their low cyclic stability, high capacity fade, and relatively low electronic conductivity that prevent their widespread use in commercial batteries. A commercially available, patented MicNo morphology of ZnO is known to adopt the advantages of nanosize into bulk in the field of semiconductor and cosmetic technology. In this study, the electrochemical performance of ZnO having MicNo morphology and its potential use in Li-ion batteries were investigated. After 100 galvanostatic cycles at constant 100 mA/g current density, the retained capacity of MicNo is higher than nanosized ZnO-the starting powder for MicNo ZnO. On the contrary, at higher current densities of 500 or 1000 mA/g, the nano-ZnO showed better cyclability and lower capacity fade compared to MicNo ZnO. In cyclic voltammetry results, reduction in ZnO, LiZn, and Li₂Zn₃ formation was dominant during formation cycle of MicNo ZnO along with excellent reversibility. After lithiation, phase change from crystalline ZnO into metallic Zn and amorphous ZnO was observed from transmission electron microscopy analysis. Improved Li⁺ diffusion in SEI and pore channels, better charge-transfer characteristics, poor electronic contact, and high EDL capacitance are other features of MicNo ZnO according to electrochemical impedance spectroscopy.