Preparation and characterization of thin electrodes for lead–acid batteries

Thin-film electrodes were prepared by spraying aqueous suspensions of soaked leady oxide over both sides of lead sheets previously heated at 150 °C. Uniform coatings of controlled thickness were obtained under optimum deposition conditions. The coatings, which retained their homogeneity after the electrochemical formation, were found to consist of small grains of β-PbO2 that tended to coalesce into micron-size units. The best electrochemical response was obtained from coatings of reduced thickness (20–40 μm). Cells were found to retain a discharge capacity in excess of 100 Ah/kg after extensive cycling. Also, electrodes exhibited excellent electrochemical performance at different discharge rates. However, if the coating was too thick, the paste was easily sulfated and the cell capacity faded after the first few cycles.