【摘要】 采用双向脉冲电流充电方法取代传统的直流电充电方法,研究了金属锂电极在有机电解液1mol·L-1LiPF6/碳酸乙烯酯(EC)∶二甲基碳酸脂(DMC)(1∶1,V/V)中的充电过程.锂电极的表面变化通过原位显微镜观测和交流阻抗谱进行检测.原位显微镜观测结果显示,在直流充电时锂电极上明显地出现了枝晶,而在双向脉冲充电时,枝晶的产生和生长受到了抑制.交流阻抗谱结果显示在双向脉冲充电下,锂电极的表面积增长较直流充电时缓慢.这种抑制枝晶生长,稳定锂沉积的新充电方法有望用于锂阳极二次电池.更多还原

【Abstract】 A bipolar pulse current charge method was developed to charge lithium metal electrode in 1 mol·L-1 LiPF6 /ethylene carbonate (EC)∶dimethyl carbonate (DMC) (1∶1, V/V) electrolyte. The surface variations of lithium electrode during charge processes were investigated by in situ optical microscopic observation and impedance measurement. It was observed that lithium dendrites formed on lithium electrode during direct current (DC) charge process, but it was inhibited by bipolar pulse charge method. The results of the impedance measurement show that the surface area increases much slower in bipolar pulse current charge process than that in DC charge process. This technique may be useful for the rechargeable lithium battery.更多还原