中文摘要：

利用恒电流沉积-溶解、交流阻抗、XRD和SEM方法研究了在室温下EC（碳酸乙烯酯）添加剂对BMImBF4离子液体作为镁沉积电解液的改善情况．在Mg（CF3S03）2浓度为0．3mol·L^-1的BMImBF4电解液中加入ω=5％（质量分数）的EC后，沉积-溶解循环过程更加稳定，并且循环次数明显增加，可以达到265次以上；交流阻抗结果显示，膜电阻和电荷转移电阻有所减少；从SEM图可以观察到，在沉积初期原本枝晶态的镁在加入EC后以颗粒状沉积．可能是EC添加剂在反应中形成的低聚物覆盖在镁的表面，抑制了枝晶的形成。

英文摘要：

The effect of ethylene carbonate （EC） additive to BMImBF4 ionic liquid as the electrolyte of magnesium deposition-dissolution was studied by constant current deposition-dissolution, AC impedance, X-ray diffraction and scanning electron microscope （SEM） measurements. After adding ω=5% EC in the ionic liquid of BMImBF4 with 0.3 mol·L^-1 Mg（CF3SO3）2, deposition-dissolution results exhibited that the process became more stable and the cyclic number was effectively improved, and impedance measurements showed that the surface film resistance and charge-transfer resistance became lower, and SEM results presented that the dendritic deposits evolved to particulate morphology and a thinner surface film was formed. The EC derived surface film, which may consist of polymeric species, suppressed the formation of dendritic magnesium.