Method for improving specific volume of low voltage aluminum anode foil

A technology of anode aluminum foil and aluminum foil, which is applied in the direction of capacitors, electrolytic capacitors, electrical components, etc., can solve the problems of increasing leakage current density, less consideration of residual chloride ion removal, and degradation of oxide film performance, so as to reduce leakage current density and promote priority The effect of growing and increasing the specific volume of aluminum foil

Active Publication Date: 2012-07-04
XI AN JIAOTONG UNIV
View PDF7 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] However, as the specific capacity of the anode aluminum foil is required to be higher and higher, the thickness of the aluminum foil used is getting thicker and the degree of corrosion is getting higher and higher. The corrosion holes are getting deeper and more complex in shape. It also becomes smaller and smaller, making it difficult to clean the etchant chloride ions in the corrosion holes thoroughly, and a large amount of chloride ions remain inside, which increases the difficulty o

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0014] 1) Electrochemical pretreatment: place the corroded aluminum foil in ammonium adipate solution with a mass concentration of 20% at 50°C, load 2V, 10mA / cm 2 The voltage and current are used for anodic oxidation, the loading time is 80S, and the exchange flow rate of the ammonium adipate solution is increased by 2 times;

[0015] 2) Formation of anode aluminum foil: place the electrochemically pretreated aluminum foil in ammonium adipate solution with a mass concentration of 5% at 90°C, load 10V, 1000mA / cm 2 The voltage and current are continuously anodized until the anode aluminum foil is formed;

[0016] 3) Heat treatment: heat-treat the formed anode aluminum foil at 550°C for 3.5 minutes;

[0017] 4) Supplementary formation: anodizing the heat-treated aluminum foil again under the conditions of step 2) to obtain a final high specific volume anode aluminum foil.

Embodiment 2

[0019] 1) Electrochemical pretreatment: place the corroded aluminum foil in ammonium adipate solution with a mass concentration of 15% at 40°C, load 5V, 50mA / cm 2 The voltage and current are used for anodic oxidation, the loading time is 40S, and the exchange flow rate of ammonium adipate solution is increased by 3 times;

[0020] 2) Formation of anode aluminum foil: place the electrochemically pretreated aluminum foil in an ammonium adipate solution with a mass concentration of 10% at 80°C, load 50V, 600mA / cm 2 The voltage and current are continuously anodized until the anode aluminum foil is formed;

[0021] 3) Heat treatment: heat-treat the formed anode aluminum foil at 600°C for 3.5, 2, 4, 3, 5 minutes;

[0022] 4) Supplementary formation: anodizing the heat-treated aluminum foil again under the conditions of step 2) to obtain a final high specific volume anode aluminum foil.

Embodiment 3

[0024] 1) Electrochemical pretreatment: place the corroded aluminum foil in ammonium adipate solution with a mass concentration of 18% at 60°C, load 3V, 200mA / cm 2 The voltage and current are used for anodic oxidation, the loading time is 60S, and the exchange flow rate of the ammonium adipate solution is increased by 1 times;

[0025] 2) Formation of anode aluminum foil: place the electrochemically pretreated aluminum foil in an ammonium adipate solution with a mass concentration of 85% at 85°C, load 30V, 300mA / cm 2 The voltage and current are continuously anodized until the anode aluminum foil is formed;

[0026] 3) Heat treatment: heat-treat the formed anode aluminum foil at 520°C for 4 minutes;

[0027] 4) Supplementary formation: anodizing the heat-treated aluminum foil again under the conditions of step 2) to obtain a final high specific volume anode aluminum foil.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides a method for improving specific volume of a low voltage aluminum anode foil, being capable of reducing chloride ion content, reducing leakage current density and improving the specific volume of the aluminum anode foil. The method provided by the invention is mainly characterized in that: chloride ion in the aluminum anode foil is separated out more rapidly by utilizing electrochemical treatment in the initial period of formation and uniform and dense aluminum oxide crystal nucleuses are formed in an aluminum foil; concentration, temperature and exchange traffic of forming liquid as well as size of on load voltage and magnitude of current are adjusted, and corrosion reaction between residual chloride ion in the aluminum foil and the aluminum foil is reduced, thus the residual chloride ion is diffused into the forming liquid; meanwhile, plenty of aluminum oxide crystal nucleuses are formed in the aluminum foil, the crystal nucleuses grow continuously in a subsequent anode oxidation process, and content of crystal alumina in a dielectric layer is improved, thus the specific volume of the aluminum anode foil is improved. Compared with untreated aluminum anode foil, the specific volume of the aluminum foil can be improved by 3-20%, and leakage current density is reduced by 40-60%. The method provided by the invention can be directly applied to the current industrial large-scale production.

Description

technical field [0001] The invention belongs to the technical field of electronic materials, and in particular relates to a method for increasing the specific capacity of an anode aluminum foil used in a low-voltage aluminum electrolytic capacitor. Background technique [0002] Alumina is the working medium of aluminum electrolytic capacitors and the core of aluminum electrolytic capacitors. The quality of its film layer determines many properties of aluminum electrolytic capacitors, such as leakage current, loss, life, capacitance, etc. Therefore, researchers have been continuously studying the formation process of alumina from theory and practice, so that the quality of alumina film has been continuously improved. Ions make it difficult to guarantee the performance of the aluminum oxide film formed by anodic oxidation, while the crystalline aluminum oxide film is beneficial to improve the performance of aluminum electrolytic capacitors. [0003] In recent years, with the ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): H01G9/055
Inventor 徐友龙杜显锋王杰毛胜春
Owner XI AN JIAOTONG UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products