JP2024509119A - Dispersion for aluminum electrolytic capacitors and aluminum electrolytic capacitors - Google Patents

Abstract

The present invention relates to the field of solid electrolytic capacitor technology, and in particular to dispersions for aluminum electrolytic capacitors and aluminum electrolytic capacitors. The dispersion includes a dispersant, a conductive polymer and an additive dispersed in the dispersant, and the additive is selected from one or more of the compounds represented by the following structural formula: and JPEG2024509119000008.jpg23170 said compound has at least one hydroxyl group and at least one ether group, R1, R2 are independently selected from a sulfur-containing group, a carbon-containing group, hydrogen, and n is 1 It is an integer between ~10. The dispersion of the present invention uses additives with polyhydroxyether structures to improve capacitance extraction and reduce equivalent resistance of aluminum electrolytic capacitors. The additive having a polyhydroxy group structure can promote crosslinking between conductive polymers and at the same time improve the tightness of the bond between the electrolyte layer produced by the conductive polymer and the dielectric layer Al2O3 film, Thereby, the capacity extraction rate of the aluminum electrolytic capacitor is improved, and the loss value and equivalent resistance of the aluminum electrolytic capacitor are reduced.

Description

The present invention relates to the technical field of solid electrolytic capacitors, and particularly to a dispersion for aluminum electrolytic capacitors and an aluminum electrolytic capacitor.

Solid electrolytic capacitors adopt solid conductive materials with high conductivity and good thermal stability as electrolytes, and compared with ordinary electrolytic capacitors, they not only have all the characteristics of ordinary electrolytic capacitors, but also It has characteristics such as good reliability, long service life, high frequency low impedance, and special resistance to large ripple current, and is widely used in computer, communication, military, industrial control and other fields, as well as cameras, video recorders, flat televisions, It can be used in a new generation of high-end finished products for consumer electronic products such as game consoles, and is advantageous for the integration and miniaturization of electronic products, and eliminates the disadvantages of liquid electrolytic capacitors such as easy leakage and short life. can be overcome. With the rapid development of China's electronic information industry and the recent development trend of polymer solid electrolytic capacitors, solid electrolytic capacitors will gradually replace ordinary low-voltage electrolytic capacitors and become the pillar of the electronic information industry in the 21st century. This will be one of the products that will become popular.

With the improvement of people's requirements for the performance of solid electrolytic capacitors, it has become a common goal of researchers to further improve the conductivity of conductive polymer electrolytes and lower the equivalent resistance (ESR value) of capacitors. ing. However, the additives currently commonly used have problems such as poor compatibility with conductive polymers and poor dispersibility, which hinders charge transfer and improvement of conductivity. It is being What is particularly important is that during the charging and discharging process, the capacity extraction rate of solid electrolytic capacitors rapidly decreases, the ESR value rapidly increases, and as a result, the performance of solid electrolytic capacitors rapidly deteriorates, leading to failure. .

Adding suitable additives into the dispersion is an effective way to improve the electrical conductivity of polymers. In the prior art, polyethylene glycol and its derivative polyglycerin are used mainly to increase the dielectric breakdown voltage. For example, a Chinese invention patent with publication number CN103429796A discloses the use of polyglycerin to reduce the ESR of capacitors containing PEDOT/PSS as the solid electrolyte, but no improvement in capacity is evident.

The aim of the present invention is to overcome the problems of low capacitance extraction and high ESR of solid electrolytic capacitors in the prior art. In order to solve the above problems, the present invention provides a dispersion for an aluminum electrolytic capacitor, and an aluminum electrolytic capacitor manufactured using the dispersion.

The technical solutions adopted by the present invention to solve the above technical problems are as follows.
A dispersion for an aluminum electrolytic capacitor is provided. The dispersion comprises a dispersant, a conductive polymer and an additive dispersed in the dispersant, the additive being selected from one or more of the compounds represented by the following structural formula: is,
The compound has at least one hydroxyl group and at least one ether group, R1 and R2 are independently selected from a sulfur-containing group, a carbon-containing group, and hydrogen, and n is an integer from 1 to 10. be. When n is 1 to 10, the water solubility of the dispersant is relatively good. If n>10, the water solubility of the dispersant decreases, affecting the overall performance of the capacitor. Preferably, n is an integer from 1 to 5.

Further, R1 and R2 are independently selected from a sulfonic acid group, a sulfuric acid group, a carbonyl group, a hydroxyacetonyl group, a propanetriol group, a propanediol group, hydrogen, and an alkyl group.

Furthermore, at least one of R1 and R2 is selected from a hydroxyacetonyl group, a propanetriol group, and a propanediol group. R1 or R2 has a hydroxyl group, or both ends have a hydroxyl group. Since the compound represented by the structural formula has both an ether bond and a hydroxyl group, it is possible to improve the tightness of the bond between the conductive polymer and the dielectric oxide layer. This is very useful for improving the capacitance of the capacitor and reducing the ESR value.

Furthermore, the additive is selected from one or more of the following compounds 1-12.

Furthermore, the content of the additive is from 0.01% to 10%, more preferably from 0.1% to 5%, based on the total mass of the dispersion. If the content of additives is too high, the viscosity of the dispersion will increase, affecting the impregnation effect and negatively affecting the performance of the capacitor. On the other hand, if the additive content is too low, the performance cannot obviously be improved.

Further, the conductive polymer is selected from one or more of polythiophene, polypyrrole, polyaniline, and derivatives thereof. Polythiophene and its derivatives are preferred. More preferred is poly(3,4-ethylenedioxythiophene).

Furthermore, the dispersant is selected from organic solvents and/or water. Preferably, the dispersant is water. Dispersions can be prepared by known methods.

The invention further provides an aluminum electrolytic capacitor. This aluminum electrolytic capacitor includes an anode body having a dielectric layer on its surface, a cathode body, a diaphragm, and a solid electrolyte layer covering at least a portion of the dielectric layer, and the solid electrolyte layer includes the above-mentioned dispersion. Manufactured by the body.

The dispersion for aluminum electrolytic capacitors and the aluminum electrolytic capacitor provided by the present invention have the following beneficial effects.
(1) The dispersion for aluminum electrolytic capacitors of the present invention uses a compound having a polyhydroxyether structure as an additive to improve capacity extraction and reduce the ESR value of aluminum electrolytic capacitors. This is because the additive with a polyhydroxy group structure promotes crosslinking _between conductive polymers and at the same time improves the tightness of the bond between the electrolyte layer and the dielectric layer _Al2O3 film produced by the conductive polymer. This is because it can be improved. As a result, the capacity extraction rate of the aluminum electrolytic capacitor is improved, and the loss value and equivalent resistance of the aluminum electrolytic capacitor are reduced.

(2) Regarding the dispersion for aluminum electrolytic capacitors of the present invention, the compound represented by the structural formula of 1≦n≦10 can be better dissolved in the dispersion and does not destroy the dispersion system. Increase in body viscosity and gelation are prevented.

In the following, the technical solution of the present invention will be clearly and completely explained with reference to specific embodiments. It should be understood that the embodiments described herein are only some, but not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative work fall within the protection scope of the present invention.

In the present invention, the core pack employed in manufacturing the electrolytic capacitor is a wound type core pack having a specification of 16V1000 and a size of 10*13.
<Example 1>

This example is intended to explain the method for manufacturing an aluminum electrolytic capacitor dispersion disclosed in the present invention and an aluminum electrolytic capacitor manufactured using the dispersion.

Compound 1 was added to PEDOT/PSS as shown in Table 1. The mass fraction of Compound 1 was 5% of the total amount of the mixed solution, which was stirred for 6 hours at room temperature using a magnetic stirrer, and then homogenized with a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention. .

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Example 2>

As shown in Table 1, the only difference in this example compared to Example 1 is that the mass fraction of Compound 1 was 0.1% of the total amount of the mixed liquid, and other parameters and The method is the same as in Example 1. Details are as follows.

Compound 1 was added to PEDOT/PSS. The mass fraction of Compound 1 was 0.1% of the total amount of the mixed solution, which was stirred for 6 hours at room temperature using a magnetic stirrer, and then homogenized with a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention. Obtained.

The electrolytic capacitor core pack was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions and dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Example 3>

As shown in Table 1, compared to Example 1, the only difference in this example is that the mass fraction of compound 1 was 3% of the total amount of the mixture, and the other parameters and methods were Same as Example 1. Details are as follows.

Compound 1 was added to PEDOT/PSS. The mass fraction of Compound 1 was 3% of the total amount of the mixed solution, which was stirred at room temperature for 6 hours using a magnetic stirrer, and then homogenized with a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention. .

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Example 4>

As shown in Table 1, the only difference in this example compared to Example 1 is that the mass fraction of compound 1 was 0.01% of the total amount of the mixed liquid, and other parameters and The method is the same as in Example 1. Details are as follows.
Compound 1 was added to PEDOT/PSS. The mass fraction of Compound 1 was 0.01% of the total amount of the mixed solution, which was stirred for 6 hours at room temperature using a magnetic stirrer, and then homogenized with a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention. Obtained.

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Example 5>

As shown in Table 1, the only difference in this example compared to Example 1 is that the mass fraction of compound 1 was 10% of the total amount of the mixture, and the other parameters and methods were Same as Example 1. Details are as follows.

Compound 1 was added to PEDOT/PSS. The mass fraction of Compound 1 was 10% of the total amount of the mixed solution, which was stirred for 6 hours at room temperature using a magnetic stirrer, and then homogenized with a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention. .

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Comparative example 1>

As shown in Table 1, compared with Example 1, the only difference of this example is that Compound 1 was not added, and other parameters and methods are the same as Example 1. Details are as follows.

PEDOT/PSS was stirred at room temperature for 6 hours using a magnetic stirrer and homogenized using a homogenizer to obtain an aluminum electrolytic capacitor dispersion of the present invention.

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Comparative example 2>

As shown in Table 1, compared with Example 1, the only difference in this example is that Compound 1 was replaced with glycerin, and other parameters and methods are the same as Example 1. Details are as follows.

Glycerin was added to PEDOT/PSS as shown in Table 1. The mass fraction of glycerin was 5% of the total amount of the mixed liquid, and the mixture was stirred at room temperature for 6 hours using a magnetic stirrer and homogenized using a homogenizer to obtain an aluminum electrolytic capacitor dispersion of the present invention.

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Comparative example 3>

As shown in Table 1, compared with Example 1, the only difference in this example is that compound 1 was replaced with polyethylene glycol 400, and other parameters and methods are the same as Example 1. . Details are as follows.

As shown in Table 1, polyethylene glycol 400 was added to PEDOT/PSS. The mass fraction of polyethylene glycol 400 was 5% of the total amount of the mixed solution, which was stirred for 6 hours at room temperature using a magnetic stirrer and homogenized using a homogenizer to obtain an aluminum electrolytic capacitor dispersion of the present invention.

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Example 6>

As shown in Table 1, the only difference in this example compared to Example 1 is that Compound 1 was replaced with Compound 2, and the mass fraction of Compound 2 was 3% of the total amount of the mixed liquid. Other parameters and methods are the same as in Example 1. Details are as follows.

Compound 2 was added to PEDOT/PSS. The mass fraction of Compound 2 was 3% of the total amount of the mixed solution, which was stirred for 6 hours at room temperature using a magnetic stirrer, and then homogenized with a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention. .

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Example 7>

As shown in Table 1, the only difference in this example compared to Example 1 is that Compound 1 was replaced with Compound 3, and the mass fraction of Compound 3 was 2% of the total amount of the mixed liquid. Other parameters and methods are the same as in Example 1. Details are as follows.

Compound 3 was added to PEDOT/PSS. The mass fraction of Compound 3 was 2% of the total amount of the mixed solution, which was stirred for 6 hours at room temperature using a magnetic stirrer, and then homogenized with a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention. .

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Example 8>

As shown in Table 1, the only difference in this example compared to Example 1 is that Compound 1 was replaced with Compound 5, and the mass fraction of Compound 5 was 1% of the total amount of the mixed liquid. Other parameters and methods are the same as in Example 1. Details are as follows.

Compound 5 was added to PEDOT/PSS. The mass fraction of Compound 5 was 1% of the total amount of the mixed solution, which was stirred for 6 hours at room temperature using a magnetic stirrer, and then homogenized using a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention. .

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Example 9>

As shown in Table 1, the only difference in this example compared to Example 1 is that Compound 1 was replaced with Compound 8, and the mass fraction of Compound 8 was 1% of the total amount of the mixed liquid. Other parameters and methods are the same as in Example 1. Details are as follows.

Compound 8 was added to PEDOT/PSS. The mass fraction of Compound 8 was 1% of the total amount of the mixed solution, which was stirred for 6 hours at room temperature using a magnetic stirrer, and then homogenized with a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention. .

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Example 10>

As shown in Table 1, compared with Example 1, the only difference in this example is that Compound 1 was replaced with Compound 4, and other parameters and methods are the same as Example 1. Details are as follows.

Compound 4 was added to PEDOT/PSS. The mass fraction of Compound 4 was 5% of the total amount of the mixed solution, which was stirred at room temperature for 6 hours using a magnetic stirrer, and then homogenized with a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention. .

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Example 11>

As shown in Table 1, compared with Example 1, the only difference in this example is that Compound 1 was replaced with Compound 6, and other parameters and methods are the same as Example 1. Details are as follows.

Compound 6 was added to PEDOT/PSS. The mass fraction of Compound 6 was 5% of the total amount of the mixed solution, which was stirred at room temperature for 6 hours using a magnetic stirrer, and then homogenized with a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention. .

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Example 12>

As shown in Table 1, compared with Example 1, the only difference in this example is that Compound 1 was replaced with Compound 7, and other parameters and methods are the same as Example 1. Details are as follows.

Compound 7 was added to PEDOT/PSS. The mass fraction of Compound 7 was 5% of the total amount of the mixed solution, which was stirred for 6 hours at room temperature using a magnetic stirrer, and then homogenized with a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention. .

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Example 13>

As shown in Table 1, compared with Example 1, the only difference in this example is that Compound 1 was replaced with Compound 9, and other parameters and methods are the same as Example 1. Details are as follows.

Compound 9 was added to PEDOT/PSS. The mass fraction of Compound 9 was 5% of the total amount of the mixed solution, which was stirred for 6 hours at room temperature using a magnetic stirrer, and then homogenized with a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention. .

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Example 14>

As shown in Table 1, compared with Example 1, the only difference in this example is that Compound 1 was replaced with Compound 10, and other parameters and methods are the same as Example 1. Details are as follows.

Compound 10 was added to PEDOT/PSS. The mass fraction of Compound 10 was 5% of the total amount of the mixed solution, which was stirred at room temperature for 6 hours using a magnetic stirrer, and then homogenized with a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention. .

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Example 15>

As shown in Table 1, compared with Example 1, the only difference in this example is that Compound 1 was replaced with Compound 11, and other parameters and methods are the same as Example 1. Details are as follows.

Compound 11 was added to PEDOT/PSS. The mass fraction of Compound 11 was 5% of the total amount of the mixed solution, which was stirred at room temperature for 6 hours using a magnetic stirrer, and then homogenized with a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention. .

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.
<Example 16>

As shown in Table 1, compared with Example 1, the only difference in this example is that Compound 1 was replaced with Compound 12, and other parameters and methods are the same as Example 1. Details are as follows.

Compound 12 was added to PEDOT/PSS. The mass fraction of Compound 12 was 5% of the total amount of the mixed solution, which was stirred for 6 hours at room temperature using a magnetic stirrer, and then homogenized with a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention. .

The core pack of the electrolytic capacitor was immersed in the aluminum electrolytic capacitor dispersion prepared in this example for 30 minutes under negative pressure conditions, and then dried. The above steps were repeated three times, and after sealing, an aluminum electrolytic capacitor was assembled.

Performance tests were conducted on the electrolytic capacitors manufactured in Examples 1 to 16 and Comparative Examples 1 to 3. An automatic electronic component analyzer was used to test the capacitance, loss value, and equivalent resistance at a frequency of 120 Hz and 100 kHz.

The test results of the above examples and comparative examples are shown in Table 2 below.

As can be seen from the data in Table 2, the electrolytic capacitor manufactured using the dispersion for aluminum electrolytic capacitors of the present invention has a capacitance (Cap) ≧1021 μF, a capacitance loss value (DF) ≦3.01%, and an equivalent resistance ( ESR)≦7.02 mΩ, and the electrolytic capacitor of the present invention has higher capacitance, lower capacitive loss value and equivalent resistance.

From the test results of Examples 1 to 5 in Table 2, it can be seen that the content of Compound 1 in the dispersion is closely related to the improvement in the conductive performance of the electrolytic capacitor. When the content of Compound 1 is between 0.1% and 5%, the performance of the electrolytic capacitor produced by the dispersion is significantly improved. When the content of Compound 1 is lower, the adsorption effect of the dispersion on the aluminum oxide film is relatively weak, and the performance of the aluminum electrolytic capacitor cannot be clearly improved. Higher content of compound 1 increases the viscosity of the dispersion, which affects the impregnation effect and at the same time negatively affects the performance of the capacitor. From the test results of Comparative Examples 1 to 3 in Table 2, compared to the conventional technology, the additive of the present invention improves the capacity extraction rate of aluminum electrolytic capacitors, and reduces the loss value and equivalent resistance of aluminum electrolytic capacitors. It can be seen that the conductive performance and stability of aluminum electrolytic capacitors can be significantly improved.

The above description is only the preferred embodiment of the present invention, and the present invention is not limited thereto, and all modifications, equivalent substitutions, improvements, etc., which may be made within the spirit and principles of the present invention are contemplated. All should be included within the protection scope of the present invention.

Claims (8)

A dispersion for an aluminum electrolytic capacitor, comprising a dispersant, a conductive polymer dispersed in the dispersant, and an additive, the additive being one of the compounds represented by the following structural formula. selected from one or more;
The compound has at least one hydroxyl group and at least one ether group, R1 and R2 are independently selected from a sulfur-containing group, a carbon-containing group, and hydrogen, and n is an integer from 1 to 10. A dispersion body characterized by a certain thing. Claim 1, wherein R1 and R2 are independently selected from a sulfonic acid group, a sulfuric acid group, a carbonyl group, a hydroxyacetonyl group, a propanetriol group, a propanediol group, hydrogen, and an alkyl group. The dispersion described in. 3. The dispersion according to claim 2, wherein at least one of R1 and R2 is selected from a hydroxyacetonyl group, a propanetriol group, and a propanediol group. Dispersion according to claim 1, characterized in that the additive is selected from one or more of the following compounds 1 to 12:
. The dispersion according to any one of claims 1 to 4, characterized in that the content of the additive is 0.01% to 10% based on the total mass of the dispersion. Dispersion according to any one of claims 1 to 4, characterized in that the conductive polymer is selected from one or more of polythiophene, polypyrrole, polyaniline and derivatives thereof. Dispersion according to claim 1, characterized in that the dispersant is selected from organic solvents and/or water. An aluminum electrolytic capacitor comprising an anode body having a dielectric layer on its surface, a cathode body, a diaphragm, and a solid electrolyte layer covering at least a part of the dielectric layer, the solid electrolyte layer comprising: An aluminum electrolytic capacitor manufactured by the dispersion method according to any one of items 1 to 7.