一维棒状ZnO的制备及电化学嵌锂性能研究

目前,商业化锂离子电池一般采用石墨作为负极材料,因其电位与金属锂电极的电位很接近,所以当电池反复循环和过充时,石墨表面易析出金属锂,会因形成枝晶而短路。在温度过高时还容易引起热失控。同时,锂离子电池的容量在很大程度上取决于负极的锂嵌入量,而且石墨材料容量相对较低

Synthesis and Electrochemical Lithium Insertion of the Rod-like ZnO

In this work, we report the synthesis of ZnO ultrafine-rods with aspect ratio of about 10 via hydrothermal method. The as-prepared rod-like ZnO are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and selected area electron diffraction (SAED). And the electrochemical performance of the ZnO material for Li-ion insertion and extraction is also investigated. It is found that the initial discharge capacity of 1 277 mAh·g^-1 and the high reversible capacity of 766 mAh·g^-1 with low Li-ion insertion potential are obtained although the cyclic stability is relatively poor. The ZnO electrode after charging is characterized by X-ray diffraction, and only metallic Zn peaks with rod-like morphology are detected. The CV measurements prove the serial formation of Li-Zn alloys during discharging and charging process.