CN1106475A - Etching technique of anode Al foil of electrolysis capacitor - Google Patents
Etching technique of anode Al foil of electrolysis capacitor Download PDFInfo
- Publication number
- CN1106475A CN1106475A CN 94118454 CN94118454A CN1106475A CN 1106475 A CN1106475 A CN 1106475A CN 94118454 CN94118454 CN 94118454 CN 94118454 A CN94118454 A CN 94118454A CN 1106475 A CN1106475 A CN 1106475A
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- CN
- China
- Prior art keywords
- aluminium foil
- corrosion
- concentration
- sulfuric acid
- temperature
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Classifications
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25F—PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR
- C25F3/00—Electrolytic etching or polishing
- C25F3/02—Etching
- C25F3/04—Etching of light metals
Abstract
The corrosive technology for anode aluminium foil of electrolytic capacitor includes immersing aluminium foil in 1-2% aqueous solution of sulfuric acid, DC electrolytic corrosion in mixture of hydrochloric acid (2-15%), sulfuric acid (2-10%), bichromate (1-20%) and F ions (0.01-1%) and then in 2-15% aqueous solution of hydrochloric acid and immersing in 10-50% aqueous solution of nitric acid, and features increasement of surface expansion rate and the specific volume of foil, and no damage to mechanical strength.
Description
The present invention relates to a kind of etching process, particularly a kind of etching process of anode aluminum foil of electrolytic capacitor.
Aluminum foil for electrolytic capacitor anode increases the electrostatic capacity (specific volume) of unit surface in order to enlarge its effective surface area, generally carries out the corrosion treatment of electrolysis or chemistry.Therefore, the relevant research that improves the area expanding rate aspect had had many reports.But the electrolytic corrosion technology in past generally is a corrosion hole when increasing, and aluminium foil surface dissolves simultaneously, causes physical strength to descend, and therefore, to improve area expanding rate significantly difficult because the restriction of physical strength makes.
At present domestic generally adopt three step factures produce the mesohigh electrolytic capacitor anode aluminum foil, promptly with the prime dc electrolysis corrosion of the mixing solutions of 20～30wt% sulfuric acid, 0.1～1.0wt% hydrochloric acid, with level dc electrolysis corrosion behind 0.05～0.1wt% phosphoric acid, the 5～10wt% hydrochloric acid mixed solution, carry out aftertreatment with 5～10wt% salpeter solution at last.
Three step factures are because the surface before lacking aluminium foil corrosion
The science and engineering skill, if there is residual oil film in aluminium foil surface, surperficial natural oxidation film thickness surpasses 60
, and the oxide film solubility property is poor, corrosion hole skewness when then causing corrosion, so this technology is tighter to the aluminium foil surface requirement, promptly this technology is not suitable for homemade aluminium foil, only is fit to use the import aluminium foil.
The prime corrosive fluid of three step factures is that sulfuric acid adds small amount of hydrochloric acid, and during corrosion, it is low that aluminium foil surface is sent out porosity, and therefore corrosion back aluminium foil specific volume is lower.
The objective of the invention is to overcome the shortcoming of above-mentioned prior art, propose a kind of area expanding rate that both improved, increased substantially specific volume, the manufacture method of not losing the electrolytic capacitor anode corrosive aluminum foil of physical strength simultaneously.
The present invention is with 70～95 ℃ of pre-treatments of soaking 1～6 minute of 1～20wt% aqueous sulfuric acid temperature, 2～15wt% hydrochloric acid, 2～10wt% sulfuric acid, 1～20wt% dichromate (as ammonium dichromate, sodium dichromate 99, potassium bichromate, chromic anhydride etc.), 0.01～1wt% fluorion (as Sodium Fluoride, hydrofluoric acid, Neutral ammonium fluoride, ammonium bifluoride etc.) mixing solutions, 50～95 ℃ of temperature, current density 5～30A/dm
2, electric weight 500～3000C/dm
2The corrosion of preceding utmost point dc electrolysis, 50～95 ℃ of 2～15wt% hydrochloric acid soln temperature, current density 0.5～10A/dm
2, electric weight 1000～5000C/dm
2The corrosion of back level dc electrolysis, 10～60 ℃ of temperature of 10～50wt% salpeter solution, soak 1～6 minute aftertreatment, four step factures are made high specific volume mesohigh electrolytic capacitor anode aluminum foil.
Details are as follows for various processes:
[pre-treatment]
Pre-treatment is mainly used in the processing of giving of aluminium foil surface, promptly remove greasy dirt, the impurity of aluminium foil surface, and natural oxide film, make aluminium foil surface even, activation, help the prime corrosion and the time form equally distributed initial pit, its method be with aluminium foil at 70～95 ℃, soaked in the aqueous sulfuric acid of concentration 1～20wt% 1～6 minute.When sulfuric acid concentration is lower than 1wt%, DeGrain, the aluminium base of aluminium foil surface dissolved by solution when surpassing 20wt%, causes aluminum foil thickness decline, optimum range at 4～9wt%.
The pre-treatment temperature is lower than 70 ℃, does not reach effect, surpasses 95 ℃ of aluminium foil surfaces and dissolves comprehensively, and aluminum foil thickness descends, and optimum temperature range is at 80～90 ℃.
The pre-treatment time is lower than 1 minute, does not reach treatment effect, but surpasses 6 minutes, and aluminium foil surface dissolves comprehensively, so the optimum handling time was at 2～4 minutes.
[prime corrosion]
Prime corrosion is the committed step of whole etching process, and in the prime corrosion step, aluminium foil surface forms the initial pit with certain depth and aperture, and initial pit requires that not only position distribution is even, and requires the pore size and the degree of depth also to be evenly distributed.
The prime corroding method is at 2～15wt% hydrochloric acid with the aluminium foil after the pre-treatment, 2～10wt% sulfuric acid, 1～20wt% dichromate (as ammonium dichromate, sodium dichromate 99, potassium bichromate, chromic anhydride etc.) carries out the dc electrolysis corrosion in 0.01～1wt% fluorion (Sodium Fluoride, hydrofluoric acid, Neutral ammonium fluoride, ammonium bifluoride etc.) mixing solutions.The corrosive fluid temperature is that 50～95 ℃, current density are 5～30A/dm
2, electric weight is 500～3000C/dm
2
In the prime corrosion process, concentration of hydrochloric acid is lower than 2wt%, and then corrosive effect is not obvious, if surpass 15wt% then aluminium foil surface dissolve comprehensively, so optimum range is at 5～9wt%.
Sulfuric acid concentration is lower than 2wt%, and the concentration of dichromate is lower than 1wt%, and then corrosive effect is not obvious, if sulfuric acid concentration surpasses 10wt%.Dichromate concentration surpass 20wt% then aluminium foil surface dissolve comprehensively, aluminum foil thickness swash reduce sharply little.Therefore sulfuric acid concentration is preferably in 5～8wt% dichromate concentration and is preferably in 6～9wt%.
When fluorinion concentration was lower than 0.01wt%, corrosive effect was not obvious, surpassed 1wt%, and then dissolving comprehensively takes place aluminium foil surface.So the fluorion optimum concn is at 0.05～0.2wt%.
Prime corrosive corrosive fluid temperature is if be lower than 50 ℃, and then corrosion speed is too slow, corrosive effect is not obvious.Then corrosion speed is too fast if surpass 95 ℃, reacts restive, and aluminium foil surface dissolves comprehensively, so temperature preferably is controlled at 80～90 ℃.
Current density is lower than 5A/dm
2, then the density of initial pit is too little, if surpass 30A/dm
2, too close by the density of initial pit, during the level reaming of back, pit merges and causes the aluminium foil surface dissolving, so current density the best should be at 10～20A/dm
2
The corrosion electric weight is if be lower than 500C/dm
2, then corrosive effect is not obvious.If surpass 3000C/dm
2, then dissolving comprehensively takes place in aluminium foil surface, so electric weight preferably is controlled at 1000～1500C/dm
2
[back level corrosion]
Back level corrosion mainly is that the initial pit that forms when prime is corroded further enlarges and deepens, and makes the aperture of final pit satisfy the high pressure requirement of energizing.
Back level corroding method is that prime corrosive aluminium foil is carried out the dc electrolysis corrosion in 2～15wt% aqueous hydrochloric acid.50～95 ℃ of corrosive fluid temperature, current density 0.5～10A/dm
2, electric weight 1000～5000C/dm
2
Concentration of hydrochloric acid is undesirable if be lower than then reaming effect of 2wt% in the level corrosive fluid of back, if surpass 15wt%, the aluminium foil surface dissolving then takes place, so optimum concn is at 5～8wt%.
Temperature is if be lower than 50 ℃ of then reaming DeGrains, if surpass 95 ℃ then aluminium foil surface comprehensive solution takes place, optimum temps should be at 75～85 ℃.
Electric weight is if be lower than 0.5A/dm
2, reaming DeGrain then is if surpass 10A/dm
2, the aluminium foil surface dissolving then takes place, so optimum current density should be at 2～4A/dm
2
Electric weight is if be lower than 1000C/dm
2, reaming DeGrain then is if surpass 5000C/dm
2, the aluminium foil surface dissolving then takes place, best charge value should be at 1500～2500C/dm
2
[aftertreatment]
Aftertreatment mainly is in order to eliminate the chlorion in aluminium foil surface metal remained impurity and the pit, eliminates the aluminium hydroxide that deposits in pit etc.
The method of aftertreatment is that the aluminium foil after the back level is corroded is in the salpeter solution of 10～50wt% in concentration, and 10～60 ℃ of liquid temperature, immersion got final product in 1～6 minute.
Concentration of nitric acid is if be lower than 10wt%, and DeGrain then is if surpass 50wt%; Comprehensive dissolving of aluminium foil then takes place, and optimum range should be at 30～40wt%.
The aluminium foil surface dissolving if surpass 60 ℃, then takes place if be lower than 10 ℃ of then DeGrains in temperature, and optimum range should be at 25～35 ℃.
Treatment time, then the paper tinsel surface dissolution then took place if surpass 6 minutes in DeGrain if be lower than 1 minute, and optimum range should be at 2～4 minutes.
Embodiment:
The homemade Dandong annealing aluminium foil of high-purity by using (99.99wt%AL) high cubic texture ((100) face occupation rate is greater than 50%) and the annealing aluminium foil of Japanese Japan aluminium (strain) are verified the technology of this invention, pre-treatment, the prime corrosion, back level corrosion, specific volume after forming in aftertreatment and the 375V boric acid solution and intensity are respectively shown in table 1～table 5:
Table 1 pre-treatment condition
Sample number light paper tinsel concentration (%) temperature (℃) time (min)
Comparative example 11 Dandong paper tinsels
Comparative example 22 Japanese paper tinsels
Embodiment 13 Dandong paper tinsels 5 90 2
Embodiment 24 Japanese paper tinsels 5 90 2
Embodiment 35 Dandong paper tinsels 5 90 2
Embodiment 46 Japanese paper tinsels 5 90 2
Table 2 prime etching condition
The sample number composition temperature current density time
(wt%) (℃) (A/dm
2) (min)
1 5%HCL 80 DC10 1.5
2 5%HCL 80 DC10 1.5
3 7%HCL+5%H
2SO
4
7%Na
2Cr
2O
7+0.1%HF 80 DC20 1
4 7%HCL+5%H
2SO
4
7%Na
2Cr
2O
7+0.1%HF 80 DC20 1
5 7%HCL+5%H
2SO
4
7%(NH
4)
2Cr
2O
7+0.1%HF 80 DC20 1
6 7%HCL+5%H
2SO
4
7%(NH
4)
2Cr
2O
7+0.1%HF 80 DC20 1
Road, table 3 back etching condition
Sample number light paper tinsel concentration (%) temperature (℃) the current density time (min)
(A/dm
2)
Comparative example 11 Dandong paper tinsels 5 85 DC4 9
Comparative example 22 Japanese paper tinsel 5 85 DC4 9
Embodiment 13 Dandong paper tinsels 6 85 DC3 9
Embodiment 24 Japanese paper tinsel 6 85 DC3 9
Embodiment 35 Dandong paper tinsels 6 85 DC3 9
Embodiment 46 Japanese paper tinsel 6 85 DC3 9
Table 4 post-treatment condition
Sample number light paper tinsel concentration (%) temperature (℃) time (min)
Comparative example 11 Dandong paper tinsels 5 30 2
Comparative example 22 Japanese paper tinsels 5 30 2
Embodiment 13 Dandong paper tinsels 35 30 2
Embodiment 24 Japanese paper tinsels 35 30 2
Embodiment 35 Dandong paper tinsels 35 30 2
Embodiment 46 Japanese paper tinsels 35 30 2
Table 5 specific volume and tensile strength
Electrostatic capacity tensile strength
Sample number (uF/CM
2) (Kg/cm)
Comparative example 11 0.45 1.5
Comparative example 22 0.55 1.6
Embodiment 13 0.92 2.13
Embodiment 24 1.05 2.08
Embodiment 35 0.93 2.11
Embodiment 46 1.07 2.10
The bulking value that the data of table 5 demonstrate embodiment 1～4 has fully had significant raising than the bulking value of comparative example 1,2, and tensile strength obviously improves.
Claims (6)
1, the etching process of anode aluminum foil of electrolytic capacitor, comprise pre-treatment, the prime corrosion, back level corrosion, four steps of aftertreatment, feature of the present invention is, aluminium foil is placed on 70～95 ℃, soaked in the aqueous sulfuric acid of concentration 1～20wt% 1～6 minute, secondly the aluminium foil after the pre-treatment being placed on concentration is 2～15wt% hydrochloric acid, 2～10wt% sulfuric acid, carry out the dc electrolysis corrosion in the mixing solutions of the fluorion of 1～20wt% dichromate and 0.01～1wt%, then the aluminium foil after the prime corrosion being placed on concentration is to carry out dc electrolysis in 2～15wt% aqueous hydrochloric acid to corrode, and at last the aluminium foil after the level corrosion of back being placed on concentration is that 10～50wt% liquid temperature is that 10～60 ℃ of immersions got final product in 1～6 minute.
2, etching process according to claim 1 is characterized in that, aluminium foil soak time in aqueous sulfuric acid is 2～4 minutes.
According to claim 1,2 described etching processs, it is characterized in that 3, the concentration of aqueous sulfuric acid is 4～9wt%, temperature is 80～90 ℃.
4, etching process according to claim 1, it is characterized in that, aluminium foil after the pre-treatment is placed on 5～9wt% hydrochloric acid, 5～8wt% sulfuric acid, 6～9wt% dichromate, in the mixing solutions of 0.05～0.2wt% fluorion, 80～90 ℃ of temperature, carry out the dc electrolysis corrosion, its current density is 10～20A/dm
2, electric weight is 1000～1500C/dm
2
5, etching process according to claim 1 is characterized in that, it is that 5～8wt% temperature is in 75～85 ℃ of hydrochloric acid solns that the aluminium foil after the prime corrosion is placed on concentration, carries out the dc electrolysis corrosion, and its current density is 2～4A/dm
2, electric weight is 1500～2500C/dm
2
6, etching process according to claim 1 is characterized in that, it is that 30～40wt% temperature is to soak 2～4 minutes in 25～35 ℃ the aqueous nitric acid that the aluminium foil after the back level corrosion is placed on concentration.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN94118454A CN1034820C (en) | 1994-12-01 | 1994-12-01 | Etching Technique of anode Al foil of electrolysis capacitor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN94118454A CN1034820C (en) | 1994-12-01 | 1994-12-01 | Etching Technique of anode Al foil of electrolysis capacitor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1106475A true CN1106475A (en) | 1995-08-09 |
| CN1034820C CN1034820C (en) | 1997-05-07 |
Family
ID=5038846
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN94118454A Expired - Fee Related CN1034820C (en) | 1994-12-01 | 1994-12-01 | Etching Technique of anode Al foil of electrolysis capacitor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1034820C (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7571626B2 (en) | 2005-09-01 | 2009-08-11 | Samsung Electronics Co., Ltd. | Drum washing machine |
| CN101174509B (en) * | 2007-10-25 | 2010-04-07 | 宁波富达电器有限公司 | Surface treating method of collecting electrode used in super capacitor |
| CN101483102B (en) * | 2009-01-08 | 2011-03-02 | 横店集团东磁有限公司 | Anode aluminum corrosion method for media and high voltage aluminum electrolysis capacitor |
| CN102094231A (en) * | 2011-01-11 | 2011-06-15 | 江苏立富电极箔有限公司 | Process for corroding anode foil for intermediate and high voltage aluminum electrolytic capacitor |
| CN103840168A (en) * | 2014-03-31 | 2014-06-04 | 福建师范大学 | Method for modifying positive aluminum-foil current collector by two-section method and by using phosphoric acid-fluorine-dichromate |
| CN105624757A (en) * | 2016-03-18 | 2016-06-01 | 西安交通大学 | Industrial-frequency alternating-current anodic oxidation method of anode aluminum foil for aluminum electrolytic capacitor |
| CN106098380A (en) * | 2016-05-26 | 2016-11-09 | 乳源县立东电子科技有限公司 | The hole shape control method of high-voltage anode foil secondary chambering |
| CN108091883A (en) * | 2017-12-19 | 2018-05-29 | 桑德集团有限公司 | A kind of collector and preparation method and lithium battery for lithium ion battery |
| CN109537040A (en) * | 2018-12-31 | 2019-03-29 | 陈建君 | The process of mesohigh Fabrication of High Specific Capacitance aluminium foil corrosion |
| WO2023184879A1 (en) * | 2022-03-29 | 2023-10-05 | 佛山市中技烯米新材料有限公司 | Current collector etched foil and preparation method therefor, electrode, and lithium battery |
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| CN1990914B (en) * | 2005-12-30 | 2010-11-17 | 新疆众和股份有限公司 | Forming technique for reducing voltage rising time of aluminum electrolytic capacitor anode foil |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5272342A (en) * | 1975-12-15 | 1977-06-16 | Hitachi Ltd | Surface treating agent for copper |
| JPS5684479A (en) * | 1979-12-13 | 1981-07-09 | Seikosha Co Ltd | Protection of copper surface |
| JPS5698479A (en) * | 1980-01-09 | 1981-08-07 | Shikoku Chem Corp | Method of coloring metal surface |
| US4432846A (en) * | 1982-12-10 | 1984-02-21 | National Steel Corporation | Cleaning and treatment of etched cathode aluminum capacitor foil |
| JPS60163423A (en) * | 1984-02-03 | 1985-08-26 | 昭和アルミニウム株式会社 | Method of etching aluminum foil for electrolytic condenser electrode |
| JPS61264183A (en) * | 1985-05-20 | 1986-11-22 | Sakamoto:Kk | Copper surface coloring agent |
| JPS6225247A (en) * | 1985-07-25 | 1987-02-03 | Nippon Denso Co Ltd | Clouding removing device for window for vehicle |
-
1994
- 1994-12-01 CN CN94118454A patent/CN1034820C/en not_active Expired - Fee Related
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| US7571626B2 (en) | 2005-09-01 | 2009-08-11 | Samsung Electronics Co., Ltd. | Drum washing machine |
| CN101174509B (en) * | 2007-10-25 | 2010-04-07 | 宁波富达电器有限公司 | Surface treating method of collecting electrode used in super capacitor |
| CN101483102B (en) * | 2009-01-08 | 2011-03-02 | 横店集团东磁有限公司 | Anode aluminum corrosion method for media and high voltage aluminum electrolysis capacitor |
| CN102094231A (en) * | 2011-01-11 | 2011-06-15 | 江苏立富电极箔有限公司 | Process for corroding anode foil for intermediate and high voltage aluminum electrolytic capacitor |
| CN103840168A (en) * | 2014-03-31 | 2014-06-04 | 福建师范大学 | Method for modifying positive aluminum-foil current collector by two-section method and by using phosphoric acid-fluorine-dichromate |
| CN103840168B (en) * | 2014-03-31 | 2016-04-13 | 福建师范大学 | By the method for two-stage method and phosphoric acid-fluorine-bichromate modification positive pole aluminium foil collector |
| CN105624757A (en) * | 2016-03-18 | 2016-06-01 | 西安交通大学 | Industrial-frequency alternating-current anodic oxidation method of anode aluminum foil for aluminum electrolytic capacitor |
| CN105624757B (en) * | 2016-03-18 | 2018-01-05 | 西安交通大学 | A kind of industrial frequency AC anodizing of aluminium electrolutic capacitor anode aluminium foil |
| CN106098380A (en) * | 2016-05-26 | 2016-11-09 | 乳源县立东电子科技有限公司 | The hole shape control method of high-voltage anode foil secondary chambering |
| CN106098380B (en) * | 2016-05-26 | 2019-02-22 | 乳源县立东电子科技有限公司 | The hole shape control method of high-voltage anode foil secondary chambering |
| CN108091883A (en) * | 2017-12-19 | 2018-05-29 | 桑德集团有限公司 | A kind of collector and preparation method and lithium battery for lithium ion battery |
| CN109537040A (en) * | 2018-12-31 | 2019-03-29 | 陈建君 | The process of mesohigh Fabrication of High Specific Capacitance aluminium foil corrosion |
| WO2023184879A1 (en) * | 2022-03-29 | 2023-10-05 | 佛山市中技烯米新材料有限公司 | Current collector etched foil and preparation method therefor, electrode, and lithium battery |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1034820C (en) | 1997-05-07 |
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Granted publication date: 19970507 Termination date: 20101201 |