IN-SITU MEASUREMENT OF LEAD ELECTRODES COMBINING CYCLIC VOLTAMMETRY AND AMPLITUDE MODULATION ATOMIC FORCE MICROSCOPY: GROWTH OF LEAD SULFATE CRYSTALS

In-situ amplitude-modulated atomic force microscopy observation was performed to clarify the process of lead sulfate crystal growth on the negative electrode surface of lead-acid batteries. At the peak of the discharge current in response to the oxidation reaction in cyclic voltammetry measurement, it was confirmed that crystals of several hundred nm, which are regarded to be lead sulfate, were thriving on the surface. After this process, when extinct the discharge current the gradual growth of the lead sulfate crystals observed continuously. From these results, it was found that the oxidation reaction (discharge) causes crystal growth in a two-step process on the negative electrode surface of the lead-acid battery.