New dynamic approach for electrochemical characterization of corrosion products in lead alloys: analysis of the formation and consolidation regions of the corrosion layer and practical application to Pb and Pb1,5%Sn alloys

ABSTRACT

The growing global electrification drives the improvement of lead-acid batteries, expanding their role in both vehicular mobility and energy storage infrastructure. This study proposes a new dynamic approach for the electrochemical characterization of corrosion products in lead alloys, dividing the analysis into two phases: (i) formation of the corrosion layer and (ii) consolidation of this layer. Cyclic voltammetry and electrochemical impedance spectroscopy were performed on samples of pure lead (Pb) and Pb1.5Sn alloy in 5M H₂SO₄ solution at 25°C, with a scan range of +1.3V to +2.2V. The tests revealed differences in the corrosion kinetics and stability of the PbO₂ layer formed. The dynamic approach showed that conclusions can vary depending on the cycle analyzed, highlighting the importance of considering the temporal evolution of reactions. The results indicate that the Pb1.5Sn alloy exhibited higher corrosion resistance throughout the cycles, as evidenced by the increase in electrochemical impedance and the stability of the PbO₂ layer. The proposed methodology enhances the interpretation of electrochemical phenomena, proving useful for optimizing material selection in lead-acid batteries.

Keywords:
Lead-acid batteries; Positive plates; Lead alloys; Corrosion