Method for Optical Analysis of Surface Structures of Lead-Acid Battery Electrodes Using a Confocal Laser Scanning Microscope

A method for analyzing electrode surfaces of lead-acid batteries has been developed. It provides a clear view on crystal structures. The technique employs confocal laser scanning microscopy (CLSM). The developed method allows examination of large areas (1 mm2 or larger) and can be applied to entire battery plates. Specimen preparation is less laborious and costly compared to scanning electron microscopy (SEM) and still gives useful results. In addition, it turned out that electrode structures vary significantly on a scale of tenth of μm. This lowers the significance of a focused image e.g. from SEM. Suitable and reproducible conditions (washing duration, drying duration and drying temperature) for the examination and preparation of electrode surfaces are investigated. The proposed method has been applied to electrodes taken from automotive flooded lead-acid batteries; scans over areas have been acquired. Electrode structures after different operating conditions are presented