阀控铅酸蓄电池板栅合金的电化学性能研究

Study on electrochemical performances of grid alloys in VRLA

系统地研究了不同板栅合金的耐腐蚀性、析气性能、表面腐蚀层阻抗等电化学性能。研究结果表明降低钙的含量,提高锡含量能使合金的耐蚀性能提高,但锡的加入会降低析氢过电位,过高的锡含量将加大电极的析氢电流,从而有可能增加电池的自放电。板栅合金的交流阻抗谱有阻抗半圆旋转现象,根据测试数据分析得出半导体等效电路比较符合具有半导体性氧化物层的板栅合金的实际情况。交流阻抗的测试结果表明锡的加入能改善钝化层的导电性。

Electrochemical performances of different grid alloys, including the performances of corrosion resistance, gassing evolution and the impedance of corrosion layer, were studied systematically. The results indicate that decreasing the content of Ca and increasing the content of Sn can improve the corrosion resistance of alloy. Sn can reduce hydrogen overvoltage and may enlarge the current of hydrogen evolution of electrode and the self-discharge of battery. The electrochemical impedance spectrum (EIS) shows that the deflexion of impedance semicircle. In accordance with experimental results, it can be concluded that the semiconductor equivalent circuit fits the real circumstances of grid alloy which has a semiconductor oxide layer. The data of EIS indicate that Sn can improve the conductivity of passive layer.