新型负极材料CrNbO4的电化学性能研究及球磨改性∗

摘要

采用高温固相法制备CrNbO4,并首次研究其作为锂离子电池负极材料的电化学性能.使用 X射线衍射分析(XRD)、扫描电子显微镜(SEM)、充放电测试、循环伏安(CV)测试和电化学交流阻抗测试(EIS)对材料的结构、形貌和电化学性能进行表征.样品 CrNbO4在0．001~3．0 V 电压区间,电流密度为16 mA/g 时,充放电50次后放电容量可以保持在63．5 mAh/g.通过球磨,CrNbO4的首次放/充电容量由212．9/100．9 mAh/g 提高到572．3/343．5 mAh/g,同时电流密度提高10倍,充放电50次后改性样品的放电容量仍可维持81．3 mAh/g,有效提高了电化学性能.%CrNbO4 was successively prepared by high solid-state method and first discussed its electrochemical properties as an anode material in lithium-ion batteries.The structure,morphology and electrochemical proper-ties were characterized using X-ray diffraction (XRD),scanning electron microscope (SEM),galvanostatic dis-charge-charge test,cyclic voltammetry (CV)and electrochemical impedance spectra (EIS).CrNbO4 can maintain a discharge capacity of 63.5 mAh/g after 50 cycles between 0.001-3.0 V at a current density of 16 mA/g.The initial dis-charge/charge capacity of sample improved from 212.9/100.9 mAh/g to 572.3/343.5 mAh/g through ball-milling meth-od,and discharge capacity kept 81.3 mAh/g after 50 cycles at a current density of 160 mA/g.