Effect of micro and nano PbO2 particles on Zn-PbO2 primary battery performances

In this work, the influence of various H2SO4/H2O/PbO ratios on the material structure and the electrochemical characteristics of PbO2 positive electrode for primary Zn-PbO2 battery are considered. The electrochemical and structural characteristics of these electrodes are investigated by ac impedance, discharge curves scanning electron microscopy (SEM) and X-ray diffraction methods. Two compositions are studied to assess the influence of H2SO4/H2O/PbO ratios. The XRD peaks of 3BS (3PbO.PbSO4H2O) of paste prepared with more acid ratio, has more intensities than others. With increasing the acid content of pastes the particles size of PbO2 after electrochemical formation, is decreased from micro to nano meter dimension and the crystals of PbO2 convert from a to b crystal type. The discharge experiments of primary Zn-PbO2 batteries exhibit an increasing in battery capacity and decreasing in battery resistance on nano PbO2 electrode. The ac impedance revealed that, the high-frequency loop in the past with nano sized PbO2 shows lower porosity and higher charge transfer resistance.

کلیدواژه ها:

Primary battery ، Positive active material ، PbO2 ، Particle size ، Performance