Cell/dendrite transition and electrochemical corrosion of Pb–Sb alloys for lead-acid battery applications

✍ Scribed by Wislei R. Osório; Daniel M. Rosa; Leandro C. Peixoto; Amauri Garcia

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 763 KB
• Volume: 196
• Category: Article
• ISSN: 0378-7753
• DOI: 10.1016/j.jpowsour.2011.03.050

✦ Synopsis

The aim of this article is focused on a comparative experimental study of the electrochemical feature of as-cast Pb-2.2 wt.% Sb alloy with cellular/dendritic transition for applications in the manufacturing of lead-acid battery parts. A water-cooled unidirectional solidification system is used to obtain the alloy samples. Electrochemical impedance spectroscopy (EIS) plots, potentiodynamic polarization curves and equivalent circuit analysis are used to evaluate corrosion resistance in a 0.5 M H 2 SO 4 solution at 25 • C. The cellular Pb-2.2 wt.% Sb alloy is found to have a current density which is of about 3 times lower than that of the dendritic Pb-2.2 wt.% Sb alloy. The Pb-2.2 wt.% Sb alloy has lower current density than both the Pb-1 wt.% Sb and the Pb-6.6 wt.% Sb alloys evidencing its potential for application as positive grid material in lead-acid batteries. It is also verified that a conventional casting with low cooling rate of about 0.6 • C s -1 produces coarser cellular spacings which is more appropriate for the manufacturing of the Pb-2.2 wt.% Sb alloys grids due to its corresponding electrochemical behavior.