Ultra-thin silver electrodes for high power density pulse batteries

Ultra-thin silver electrodes for high power density pulse batteries are prepared by anodic oxidation and cathodic reduction of thin silver foils in 0.1 mol/l HCl aqueous solution. The active layer thus formed has a porosity about 65%. The thickness of the active layer can be controlled by the charge passed in oxidation. Typically, silver foils 50 μm thick are used as the raw material and finished in 80 μm electrodes with nominal capacity 14 C/cm2 on each side. These electrodes can be charged and discharged at very high rates (typically 10C charge and 102C discharge) with about 90% utilization of the active material. Potential valleys, most possibly due to the resistive Ag2O, are observed on both steady-state and pulse discharges. To prevent the potential valleys, which are most annoying to pulse applications, charging is suggested to be confined within the low potential plateau region.