Research Of Technological Parameters On Anode Foil For Aluminum Electrolytic Capacitor

With the development of technology, electronic product trends toward miniaturization and integration. The surface corrosion of anode aluminum foil is the effective method to increase the capacity of electrolytic capacitors. This is the key point in the research.This thesis summarizes the current studies and prospects of surface corrosion of aluminum foil for aluminum electrolytic capacitor and describes direct current etching of high pure aluminum foil for area-enlarging in inorganic mixture acid. The effects of aluminum foil direct current corrosion process on the specific capacitance were investigated. The influences of inhibitor on the specific capacitance had also been researched to obtain the large surface area of etched foils. Layered double hydroxide was also combined with aluminum foils in the experiment. To some extent, aluminum foils were increased the specific capacitance while maintaining a good surface quality of aluminum foil.With the development of science and technology,the demands of electronic products trend toward miniaturization and integration. Modern electronics market demands for low volume and high specific capacity of aluminum electrolytic capacitor. The key to minimize the aluminum electrolytic capacitors is aluminum foil with high specific volume, which is the subject of this article.The corrosion process was divided into two steps, the first corrosion process and the second corrosion process. The optimal parameters of the process were investigated by single factor experiments. The optimal parameters of the first corrosion process were obtained: the etching solution is composed of 1 mol/L HCl and 1 mol/L H2SO4, etching temperature is 60 ?, current density is 350 mA/cm2, etching duration is 90 s. The optimal parameters of the second corrosion process were also concluded: the etching solution is 2 mol/L HCl, etching duration is 150 s, current density is 150 mA/cm2.On the basis of previous experiments, effect of corrosion inhibitor on the specific capacitance of high-voltage anode foil was investigated. With the addition of corrosion inhibitor in the second etching solutions, the etched foils were maintained the pit density and distribution of the pits tended to be uniform, furthermore, phenomenon of excessive corrosion of etched foil reduced and weight loss decreased. In the work, effects of Polyethylene glycol, ethylene glycol, diethanolamine, triethanolamine on the specific capacitance of high-voltage anode foil were investigated.Layered double hydroxide was electrodeposited on aluminum foils in the experiment. The results indicate that surface morphology of aluminum foil is not affected by electrodeposition, but aluminum foil specific capacitance was promoted.