CN102842434B - A kind of cathode preparation method of electrolytic capacitor - Google Patents
A kind of cathode preparation method of electrolytic capacitor Download PDFInfo
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- CN102842434B CN102842434B CN201210326942.XA CN201210326942A CN102842434B CN 102842434 B CN102842434 B CN 102842434B CN 201210326942 A CN201210326942 A CN 201210326942A CN 102842434 B CN102842434 B CN 102842434B
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- manganese nitrate
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- nitrate solution
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Abstract
The invention discloses a kind of cathode preparation method of electrolytic capacitor, using as anode metal derby containing in the manganese nitrate solution being immersed in different specific weight for several times, the proportion 1.10 ~ 1.90 of manganese nitrate solution, increase with number of times, proportion is ascending, during each impregnation, manganese nitrate all generates manganese dioxide at 200 DEG C ~ 270 DEG C, form the outer metal derby containing manganese dioxide, also comprise preparation manganese nitrate mixed solution step: be in the manganese nitrate solution of 1.10 ~ 1.30 at proportion, add the Powdered inserts of this manganese nitrate solution weight 30% ~ 70% and the graphite of this manganese nitrate solution weight 30% ~ 70%, the nanoscale carbon dust that inserts is 1:1 ~ 5 by weight ratio becomes with mixed with resin, impregnation decomposition step: by above-mentioned metal derby containing in the manganese nitrate mixed solution being immersed in preparation for several times, at 200 ~ 270 DEG C, manganese nitrate generates manganese dioxide, and Powdered inserts and graphite are blended in manganese dioxide, forms negative electrode.
Description
Technical field
The present invention relates to the preparation of electrolytic capacitor, particularly relate to a kind of cathode preparation method of electrolytic capacitor.
Background technology
Along with a large amount of of intelligent portable electronic equipment popularize, there is provided power supply to IC in such devices and as the capacitor requirement of power filter, there is less equivalent series resistance (Equivalent Series Resistance, ESR), therefore electric capacity must adapt to new requirement.The current approach improving product E SR mainly contains following several: 1, change product structure: multianode designs; 2, cathode material is changed: use the conducting polymer that conductivity is higher; 3, the associativity between product negative electrode extraction material and compatibility is improved.But no matter which kind of approach to improve ESR by, the 3rd kind of approach is all applicable, and is absolutely necessary.
For tantalum electrolytic capacitor, Fig. 1 is its negative electrode deriving structure schematic diagram, its ESR=R
be situated between+ R
separate+ R
gold, wherein R
be situated betweenrepresent the resistance of dielectric oxide film, R
goldrepresent that negative electrode draws the resistance of layer, R
separatecomprise the contact resistance of manganese dioxide self-resistance, manganese dioxide layer and graphite linings, graphite linings self-resistance, graphite linings and silver layer contact resistance, silver layer resistance, in this several resistance, contact resistance is more important relative to the resistance of each material self, its reduction can make the ESR of whole capacitor obviously reduce on the one hand, and it also affects the stability of properties of product to a great extent on the other hand.
Summary of the invention
Technical problem to be solved by this invention is: make up above-mentioned the deficiencies in the prior art, proposes a kind of cathode preparation method of electrolytic capacitor, effectively can reduce the ESR of electrolytic capacitor.
Technical problem of the present invention is solved by following technical scheme:
A kind of cathode preparation method of electrolytic capacitor, containing manganese dioxide solid in the negative electrode of described electrolytic capacitor, comprise the steps: using as anode metal derby containing in the manganese nitrate solution being immersed in different specific weight for several times, the proportion of described manganese nitrate solution is 1.10 ~ 1.90, and with the increase of impregnation number of times, the proportion of manganese nitrate solution is ascending, during each impregnation, manganese nitrate all decomposes generation manganese dioxide at 200 DEG C ~ 270 DEG C, to form the outer metal derby containing manganese dioxide, also comprise the steps:
Preparation manganese nitrate mixed solution step: be in the manganese nitrate solution of 1.10 ~ 1.30 at proportion, add the Powdered inserts of this manganese nitrate solution weight 30% ~ 70% and the graphite of this manganese nitrate solution weight 30% ~ 70%, described Powdered inserts is that the nanoscale carbon dust of 1:1 ~ 5 and mixed with resin form by weight ratio;
Impregnation decomposition step: the metal derby described skin being contained manganese dioxide containing in the manganese nitrate mixed solution being immersed in above-mentioned preparation for several times, at 200 ~ 270 DEG C, manganese nitrate decomposes generation manganese dioxide, make described Powdered inserts and graphite be blended in manganese dioxide, complete the manufacture of described negative electrode.
Preferably, the particle diameter of described Powdered inserts is 100 ~ 200nm, and thus, accordingly, the particle diameter of nanoscale carbon dust is 100 ~ 200nm, and the particle diameter of toner is also 100 ~ 200nm.
Preferably, the addition of described Powdered inserts is 60% ~ 70% of manganese nitrate solution weight.
Preferably, described resin is polyvinyl alcohol, and its molecular weight is 150 ~ 250D.
Preferably, described electrolytic capacitor is tantalum electrolytic capacitor or niobium electrolytic capacitor.
For mixing the inserts in electrolytic capacitor cathode, be that the nanoscale carbon dust of 1:1 ~ 5 and mixed with resin form by weight ratio.
Preferably, described resin is polyvinyl alcohol, and its molecular weight is 150 ~ 250D.
Preferably, the particle diameter of described nanoscale carbon dust is 100 ~ 200nm.
A negative electrode for electrolytic capacitor, is obtained by the preparation method described in above-mentioned any one.
A kind of electrolytic capacitor, comprises above-mentioned negative electrode.
The beneficial effect that the present invention is compared with the prior art is: in manganese nitrate solution, add the evenness that Powdered inserts can improve manganese dioxide cathodes layer, thus improves the contact of manganese dioxide layer and graphite linings, reduces ESR.
Accompanying drawing explanation
Fig. 1 is the negative electrode deriving structure schematic diagram of tantalum electrolytic capacitor in prior art.
Embodiment
Below in conjunction with preferred embodiment, the present invention is explained in detail.
The invention provides a kind of cathode preparation method of electrolytic capacitor, containing manganese dioxide solid in the negative electrode of described electrolytic capacitor, in one embodiment, comprise the steps: using as anode metal derby containing in the manganese nitrate solution being immersed in different specific weight for several times, the proportion of described manganese nitrate solution is 1.10 ~ 1.90, and with the increase of impregnation number of times, the proportion of manganese nitrate solution is ascending, during each impregnation, manganese nitrate all decomposes generation manganese dioxide at 200 DEG C ~ 270 DEG C, to form the outer metal derby containing manganese dioxide, also comprise the steps: preparation manganese nitrate mixed solution step: be in the manganese nitrate solution of 1.10 ~ 1.30 at proportion, add the Powdered inserts of this manganese nitrate solution weight 30% ~ 70% and the graphite of this manganese nitrate solution weight 30% ~ 70%, described Powdered inserts is that the nanoscale carbon dust of 1:1 ~ 5 and mixed with resin form by weight ratio, impregnation decomposition step: the metal derby described skin being contained manganese dioxide containing in the manganese nitrate mixed solution being immersed in above-mentioned preparation for several times, at 200 ~ 270 DEG C, manganese nitrate decomposes generation manganese dioxide, described Powdered inserts and graphite are blended in the manganese dioxide of impregnation decomposition step generation, complete the manufacture of described negative electrode.
When early stage manganese nitrate decompose generate manganese dioxide capacity enough after, along with later stage manganese nitrate proportion improves, the content of inner silica manganese can increase, also rough surface state can be formed during reaction, manganese nitrate solution improve gradually proportion decompose after (also namely as the metal derby of anode containing being immersed in manganese nitrate solution for several times, with the increase of number of times, manganese nitrate from thin to thick), form the outer metal derby containing manganese dioxide, now, the number of times of impregnation is good with the thickness of the cathode layer formed with 0.07-0.08mm, and then in the manganese nitrate solution of proportion less (proportion is 1.10 ~ 1.30), add a certain amount of Powdered inserts and graphite, and the metal derby skin formed before being contained manganese dioxide is containing being immersed in this solution for several times, the number of times of impregnation is good to increase the thickness of 0.04 ~ 0.05mm, also namely the thickness of the final cathode layer formed is no more than 0.12 ~ 0.13mm is good, experiment proves, impregnation is advisable for 2 ~ 3 times, during each impregnation, manganese nitrate resolves into manganese dioxide, Powdered inserts and graphite is made to be blended in manganese dioxide cathodes layer, inserts can fill concavo-convex place, it is made to form relatively fine and close and smooth surface state, improve the evenness of manganese dioxide cathodes layer, thus reduce the contact resistance of manganese dioxide, the area of the manganese dioxide of opposed flattened can increase thus improve the contact between manganese dioxide layer and graphite linings.
Experiment proves, after adding this inserts, the ESR of product can reduce by 10% ~ 30%.
In a preferred embodiment, the particle diameter of Powdered inserts is 100 ~ 200nm, and thus, accordingly, the particle diameter of nanoscale carbon dust is 100 ~ 200nm, and the particle diameter of toner is also 100 ~ 200nm.
In a preferred embodiment, the addition of Powdered inserts is 60% ~ 70% of manganese nitrate solution weight.
In a preferred embodiment, described resin is polyvinyl alcohol, and its molecular weight is 150 ~ 250D.
Preferably, described electrolytic capacitor is tantalum electrolytic capacitor or niobium electrolytic capacitor.
The present invention also provides a kind of inserts for mixing in electrolytic capacitor cathode, is that the nanoscale carbon dust of 1:1 ~ 5 and mixed with resin form, preferably by weight ratio, described resin is polyvinyl alcohol, its molecular weight is 150 ~ 250D, and preferably, the particle diameter of described nanoscale carbon dust is 100 ~ 200nm.
Below by way of embodiment more specifically, the present invention will be described in detail.
embodiment one
Using as anode tantalum block containing in the manganese nitrate solution being immersed in different specific weight for several times, the proportion of manganese nitrate solution is 1.10 ~ 1.90, and with the increase of impregnation number of times, the proportion of manganese nitrate solution is ascending, during each impregnation, manganese nitrate all decomposes generation manganese dioxide at 200 DEG C ~ 270 DEG C, to form the outer metal derby containing manganese dioxide, then carries out following steps:
Preparation manganese nitrate mixed solution step: be in the manganese nitrate solution of 1.10 at proportion, (addition of certain graphite can also be other values in 30% ~ 70% to add the graphite of the Powdered inserts of this manganese nitrate solution weight 30% and this manganese nitrate solution weight 30%, factor mainly Powdered inserts and the addition thereof of the ESR of product is affected) in the present invention, Powdered inserts is that the nanoscale carbon dust of 1:1 and polyvinyl alcohol mix and form by weight ratio, and the molecular weight of polyvinyl alcohol is 250D.
Impregnation decomposition step: the metal derby above-mentioned skin being contained manganese dioxide is containing in the manganese nitrate mixed solution being immersed in above-mentioned preparation 2 ~ 3 times, during each impregnation, all at 200 ~ 270 DEG C, manganese nitrate decomposes generation manganese dioxide, make Powdered inserts and graphite be blended in manganese dioxide, complete negative electrode manufacture thus.By the negative electrode obtained in the present embodiment further method routinely obtain tantalum electrolytic capacitor, recording its ESR is 1.0 Ω.
embodiment two
Be with the difference of embodiment one: prepare in manganese nitrate mixed solution step, the proportion of manganese nitrate solution is 1.30, the addition of Powdered inserts is 40% of this manganese nitrate solution weight, the addition of graphite is that the 40%(of this manganese nitrate solution weight is with embodiment one, the addition of graphite can also be other values in 30% ~ 70%, factor mainly Powdered inserts and the addition thereof of the ESR of product is affected) in the present invention, Powdered inserts is that the nanoscale carbon dust of 1:2 and polyvinyl alcohol mix and form by weight ratio, and the molecular weight of polyvinyl alcohol is 170D.By the negative electrode obtained in the present embodiment further method routinely obtain tantalum electrolytic capacitor, recording its ESR is 0.8 Ω.
embodiment three
Be with the difference of embodiment one: prepare in manganese nitrate mixed solution step, the proportion of manganese nitrate solution is 1.20, the addition of Powdered inserts is 50% of this manganese nitrate solution weight, the addition of graphite is that the 50%(of this manganese nitrate solution weight is with embodiment one, the addition of graphite can also be other values in 30% ~ 70%, factor mainly Powdered inserts and the addition thereof of the ESR of product is affected) in the present invention, Powdered inserts is that the nanoscale carbon dust of 1:3 and polyvinyl alcohol mix and form by weight ratio, and the molecular weight of polyvinyl alcohol is 150D.By the negative electrode obtained in the present embodiment further method routinely obtain tantalum electrolytic capacitor, recording its ESR is 0.7 Ω.
embodiment four
Be with the difference of embodiment one: prepare in manganese nitrate mixed solution step, the proportion of manganese nitrate solution is 1.20, the addition of Powdered inserts is 60% of this manganese nitrate solution weight, the addition of graphite is that the 60%(of this manganese nitrate solution weight is with embodiment one, the addition of graphite can also be other values in 30% ~ 70%, factor mainly Powdered inserts and the addition thereof of the ESR of product is affected) in the present invention, Powdered inserts is that the nanoscale carbon dust of 1:5 and polyvinyl alcohol mix and form by weight ratio, and the molecular weight of polyvinyl alcohol is 150D.By the negative electrode obtained in the present embodiment further method routinely obtain tantalum electrolytic capacitor, recording its ESR is 0.6 Ω.
embodiment five
Be with the difference of embodiment one: prepare in manganese nitrate mixed solution step, the proportion of manganese nitrate solution is 1.20, the addition of Powdered inserts is 70% of this manganese nitrate solution weight, the addition of graphite is that the 70%(of this manganese nitrate solution weight is with embodiment one, the addition of graphite can also be other values in 30% ~ 70%, factor mainly Powdered inserts and the addition thereof of the ESR of product is affected) in the present invention, Powdered inserts is that the nanoscale carbon dust of 1:5 and polyvinyl alcohol mix and form by weight ratio, and the molecular weight of polyvinyl alcohol is 150D.By the negative electrode obtained in the present embodiment further method routinely obtain tantalum electrolytic capacitor, recording its ESR is 0.4 ~ 0.5 Ω.
comparative example
Using as anode tantalum block containing in the manganese nitrate solution being immersed in different specific weight for several times, also graphite is added with in manganese nitrate solution, the proportion of manganese nitrate solution is 1.10 ~ 1.90, and with the increase of impregnation number of times, the proportion of manganese nitrate solution is ascending, and during each impregnation, manganese nitrate solution all decomposes generation manganese dioxide at 200 DEG C ~ 270 DEG C, manganese dioxide and graphite are mixed to form at the metal derby of anode outer, as negative electrode.By negative electrode obtained in this comparative example further method routinely obtain tantalum electrolytic capacitor, recording its ESR is 1.5 Ω.
The present invention also provides a kind of negative electrode of electrolytic capacitor, is obtained by the preparation method of above-mentioned any embodiment.
The present invention also provides a kind of electrolytic capacitor, comprises above-mentioned negative electrode.
Above content is in conjunction with concrete preferred implementation further description made for the present invention, can not assert that specific embodiment of the invention is confined to these explanations.For general technical staff of the technical field of the invention, without departing from the inventive concept of the premise, make some equivalent to substitute or obvious modification, and performance or purposes identical, all should be considered as belonging to protection scope of the present invention.
Claims (6)
1. the cathode preparation method of an electrolytic capacitor, containing manganese dioxide solid in the negative electrode of described electrolytic capacitor, comprise the steps: using as anode metal derby containing in the manganese nitrate solution being immersed in different specific weight for several times, the proportion of described manganese nitrate solution is 1.10 ~ 1.90, and with the increase of impregnation number of times, the proportion of manganese nitrate solution is ascending, during each impregnation, manganese nitrate all decomposes generation manganese dioxide at 200 DEG C ~ 270 DEG C, to form the outer metal derby containing manganese dioxide, it is characterized in that, also comprise the steps:
Preparation manganese nitrate mixed solution step: be in the manganese nitrate solution of 1.10 ~ 1.30 at proportion, add the Powdered inserts of this manganese nitrate solution weight 60% ~ 70% and the graphite of this manganese nitrate solution weight 30% ~ 70%, described Powdered inserts is that the nanoscale carbon dust of 1:1 ~ 5 and mixed with resin form by weight ratio;
Impregnation decomposition step: the metal derby described skin being contained manganese dioxide containing in the manganese nitrate mixed solution being immersed in above-mentioned preparation for several times, at 200 ~ 270 DEG C, manganese nitrate decomposes generation manganese dioxide, the number of times of impregnation is enough to the thickness of increase by 0.04 ~ 0.05mm, make described Powdered inserts and graphite be blended in manganese dioxide, complete the manufacture of described negative electrode.
2. the cathode preparation method of electrolytic capacitor as claimed in claim 1, is characterized in that: the particle diameter of described Powdered inserts is 100 ~ 200nm.
3. the cathode preparation method of electrolytic capacitor as claimed in claim 1, it is characterized in that: described resin is polyvinyl alcohol, its molecular weight is 150 ~ 250D.
4. the cathode preparation method of electrolytic capacitor as claimed in claim 1, is characterized in that: described electrolytic capacitor is tantalum electrolytic capacitor or niobium electrolytic capacitor.
5. a negative electrode for electrolytic capacitor, is characterized in that: obtained by the preparation method described in claim 1-4 any one.
6. an electrolytic capacitor, is characterized in that: comprise negative electrode according to claim 5.
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| CN109300695B (en) * | 2018-11-06 | 2020-10-16 | 中国振华(集团)新云电子元器件有限责任公司(国营第四三二六厂) | Cathode of low ESR tantalum electrolytic capacitor and preparation method thereof |
| CN114974901B (en) * | 2022-06-07 | 2023-05-23 | 中国振华(集团)新云电子元器件有限责任公司(国营第四三二六厂) | Coating method for improving capacitance extraction rate of tantalum capacitor |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4945452A (en) * | 1989-11-30 | 1990-07-31 | Avx Corporation | Tantalum capacitor and method of making same |
| EP0633583A1 (en) * | 1993-07-05 | 1995-01-11 | Nec Corporation | Low impedance solid electrolytic capacitor and method for fabricating the same |
| CN1776847A (en) * | 2005-11-18 | 2006-05-24 | 中国振华（集团）新云电子元器件有限责任公司 | Method for preparing solid electrolytic capacitor cathode |
| CN101404212A (en) * | 2008-11-13 | 2009-04-08 | 北京七一八友益电子有限责任公司 | Sheet type niobium oxide solid electrolyte capacitor and its manufacturing method |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11274009A (en) * | 1998-03-26 | 1999-10-08 | Hitachi Chem Co Ltd | Solid electrolytic capacitor and manufacture thereof |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4945452A (en) * | 1989-11-30 | 1990-07-31 | Avx Corporation | Tantalum capacitor and method of making same |
| EP0633583A1 (en) * | 1993-07-05 | 1995-01-11 | Nec Corporation | Low impedance solid electrolytic capacitor and method for fabricating the same |
| CN1776847A (en) * | 2005-11-18 | 2006-05-24 | 中国振华（集团）新云电子元器件有限责任公司 | Method for preparing solid electrolytic capacitor cathode |
| CN101404212A (en) * | 2008-11-13 | 2009-04-08 | 北京七一八友益电子有限责任公司 | Sheet type niobium oxide solid electrolyte capacitor and its manufacturing method |
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