A kind of manufacturing method of electrode foil of non-phosphorus expanded aluminum electrolytic capacitor

Abstract

The invention provides a method for manufacturing an electrode foil of a phosphorus-free expanded hole aluminum electrolytic capacitor. In this method, a certain amount of oxalic acid or oxalate is added to the mixed aqueous solution containing aluminum nitrate and polyethanol ion active agent, so that the corrosion inhibition effect of phosphoric acid and phosphate can be replaced. The manufacturing method of the aluminum electrolytic capacitor electrode foil of the present invention uses oxalic acid and oxalate to replace the corrosion inhibition effect of phosphoric acid and phosphate, which can save all phosphoric acid costs and reduce environmental pollution. conditions, improve the uniformity of the holes in the hole expansion stage, reduce the strong self-corrosion reaction of the aluminum foil in the case of non-phosphorus hole expansion, and obtain a medium-high pressure corrosion foil with uniform corrosion on the aluminum surface and high consistency. The specific volume of the electrode foil is high, The bending strength is good, and the specific surface area is increased by 8-13%. After the light foil with a thickness of 123um is corroded, the specific capacitance value of 520V reaches 0.78-0.81μF / cm 2 , The bending strength reaches 55-65 times / N.

Description

technical field [0001] The invention relates to the technical field of corroded foil electrodes, in particular to a method for manufacturing an electrode foil of a phosphorus-free expanded hole aluminum electrolytic capacitor. Background technique [0002] For capacitors, the electrode foil is the most important component, and the electrode foil is required to have characteristics such as high strength, low loss, long life, and low leakage current. The corrosion process of the electrode foil is based on the electronic light foil as the raw material, and the electrode light foil is etched by an electrochemical method to form holes on the surface, thereby increasing the specific surface area of ​​the light foil and improving the corrosion capacity. In the existing domestic medium and high pressure corrosion foil manufacturing methods, the hole expansion process is generally an electrochemical pore expansion electrolyte of a mixture of nitric acid and phosphoric acid or an elec...

AI Technical Summary

Problems solved by technology

Prior art CN108183033A discloses an anode foil corrosion process for aluminum electrolytic capacitors. In this process, it is disclosed that complexing agents such as oxalic acid are added to the pore corrosion solution to improve the mass transfer rate of free aluminum ions in the tunnel holes and prevent aluminum Ions are enriched and hydrolyzed in the tunnel pores, but phosphoric acid is still required in the disclosed pore expansion industry, and phosphorus-free pore expansion cannot be achieved