The effect of surfactants on the efficiency of lead acid batteries

The aim of this study is to show the effect of two phosphonate surfactants (PS) on the electrochemical behavior of the negative plate of lead-acid battery in the sulfuric acid medium. The characterization of the electrode interface was investigated at room temperature by a set of electrochemical techniques as linear sweep voltammetry (LSV), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and chronoamperometry (CA). Scanning electron microscopy (SEM) was employed to determine the film layer's morphology deposited on the surface of working electrodes, in the presence and in the absence of the PS. When the PS was added in the acidic solution, hydrogen evolution became higher, the over-potential of hydrogen was shifted to negatives values and the growth of the anodic β-PbO2 was inhibited. SEM imaging with the presence of PS showed reduction in the growth of the anodic β-PbO2 and PbSO4 layers. EIS results indicate the decrease of the conductivity of β-PbO2 film on the lead surface electrode. The result of the CV, show a decrease in the peak related to transition of PbO to Pb demonstrates that lower PbO has been formed underneath the lead sulfate membrane in the presence of low concentration of SP indeed a decrease in the amount of formed PbSO4 on the electrode surfac

The Influence of the Second Fusion on the Microstructure and Electrochemical Behaviour of Algerian Zinc

International audienceZinc from the Algerian metallurgy industry (zinc A) was compared with specimens of the same zinc following fusion treatment at 500°C for 60 minutes and cooling according to three different kinetics. The treated materials are designated by B, C, and D. The fusion/cooling treatment modified the microstructural state of the metal. The different microstructural states were revealed by X-ray diffraction. Electrochemical studies of the treated zinc specimens were performed using voltammetry, potentiometry and electrochemical impedance spectroscopy (EIS). Only a significant variation in EIS results was found. The EIS diagrams of the materials varied with immersion times. The variations in low frequency resistance were directly correlated with the microstructural states of the specimens. The results of the study indicate that fusion treatment at 500°C for 60 minutes and cooling by nitrogen to 10 l min-1 is the most suitable for use as a sacrificial anode

A comparative study of the electrochemical behaviour of Algerian zinc and a zinc from a commercial sacrificial anode

International audienceZinc is used in the oil industry as a sacrificial anode for protecting steel storage tanks from corrosion. The behaviour of a sample of zinc from the Algerian metallurgy industry (zinc A) and a commercially available zinc (zinc B) was compared in an electrolyte from storage tank drainage water. The corrosion potential measurements for zinc A confirmed that this material could be used as a sacrificial anode. The polarization curves of the two materials (zinc A and zinc B) were different, zinc A being the least polarized. Thus, the same corrosion protection could be obtained with a lower surface ratio (S Zn/S Fe) for Zinc A. Cyclic voltammetry curves provided evidence of a surface layer formed by dissolution products. To provide protection over extended periods of time, the zinc anode must be oversized. The two types of zinc tested were comparable. The results of the impedance spectroscopy study confirmed the previous results. The corrosion layer formed on zinc A was not prejudicial to dissolution. Hence, the properties of this zinc were found to be satisfactory for its use as a sacrificial anode