卷绕铅酸电池泡沫铅负极电化学行为的研究

以泡沫铅作为负极集流体制备了卷绕VRLA电池.采用计时电流法、循环伏安曲线、电化学阻抗谱和充放电实验研究了泡沫铅负极的电化学行为,结果表明泡沫铅负极的真实表面积比铅箔负极的大,因此泡沫铅负极具有较低的过电势,并且不论是在怎样的放电状态下,泡沫铅负极的电化学反应电阻较小;与铅箔负极相比,在10、5和2小时率放电状态下,泡沫铅负极的质量比容量分别增加25.9%,30.0%和48.2%.此外,SEM观察显示,泡沫铅负极表面活性物质为更加细小的晶体颗粒和具有更高的孔率.

Electrochemical Behavior of Lead Foam Negative Electrode in Spiral VRLA Batteries

Spirally valve-regulated lead acid (VRLA) batteries were prepared by using lead foam as the negative current collectors material. The electrochemical behaviors of a lead foam negative electrode in sulfuric acid were studied by means of chronoamperometry,cyclic voltammetry (CV), electrochemical impedance spectrometry (EIS) and charge-discharge tests. The results show that the real surface area of a lead foam negative electrode is larger than that of a lead foil negative electrode, while the overpotential of the lead foam negative electrode is lower. The electrochemical reaction resistance of a lead foam negative electrode is always smaller than that of a lead foil negative electrode under whatever depth of discharge. Compared with those of a lead foil negative electrode, the mass specific capacities of a lead foam negative electrode are 25.9%, 30.0% and 48.2% higher at 10h, 5h and 2h discharge rates, respectively. Besides, the observation of SEM shows that the active material on the lead foam negative electrode has smaller crystals and higher porosity.