A dispersion for aluminum electrolytic capacitor and aluminum electrolytic capacitor

Abstract

The present invention relates to the technical field of solid electrolytic capacitors, and in particular to a dispersion for aluminum electrolytic capacitors and aluminum electrolytic capacitors. The dispersion includes a dispersant, and a conductive polymer and an additive dispersed in the dispersant, wherein the additive is selected from one or more of the compounds shown in the following structural formula, wherein the compound has at least one hydroxyl group and at least one ether group, wherein R1 and R2 are independently selected from sulfur-containing groups, carbon-containing groups, and hydrogen, and n is an integer of 1-10. The dispersion of the present invention uses an additive with a polyhydroxy ether structure to increase the capacity extraction of aluminum electrolytic capacitors and reduce the equivalent resistance. The additive with a polyhydroxy structure can promote the cross-linking effect between conductive polymers, and at the same time can improve the electrolytic layer generated by the conductive polymer and the dielectric layer Al 2 O 3 The bonding tightness of the film increases the capacity extraction rate of the aluminum electrolytic capacitor and reduces the loss value and equivalent resistance of the aluminum electrolytic capacitor.

Description

Technical Field

[0001] The present invention relates to the technical field of solid electrolytic capacitors, and in particular to a dispersion for aluminum electrolytic capacitors and an aluminum electrolytic capacitor. Background Art

[0002] Solid electrolytic capacitors use solid conductive materials with high conductivity and good thermal stability as electrolytes. Compared with ordinary electrolytic capacitors, they not only have all the characteristics of ordinary electrolytic capacitors, but also have good reliability, long service life, high frequency and low impedance, and resistance to extremely large ripple current. They can be used in the fields of computers, communications, military, industrial control, and in the new generation of high-end complete products of consumer electronic products such as cameras, video recorders, flat-screen TVs, and game consoles. They are conducive to the integration and miniaturization of electronic products, and can overcome the disadvantages of liquid electrolytic capacitors that they are prone to leakage and have a short life.

[0003] With the rapid development of the domestic electronic information industry, judging from the development trend of polymer solid electrolytic capacitors in recent years, solid electrolytic capacitors will gradually replace ordinary low-voltage electrolytic capacitors and will become one of the pillar products of the electronic information industry in the 21st century.

[0004] As people's requirements for the performance of solid electrolytic capacitors increase, further improving the conductivity of conductive polymer electrolytes and reducing the equivalent resistance (ESR value) of capacitors have become the common goals pursued by researchers.

[0005] However, currently commonly used additives have problems such as poor compatibility and poor dispersibility with conductive polymers, which hinder the transfer of charges and the improvement of conductivity.

[0006] What is particularly important is that during the charge and discharge process, the capacity extraction rate of the solid electrolytic capacitor will drop rapidly and the ESR value will increase rapidly, causing the solid electrolytic capacitor to rapidly deteriorate in performance and fail.

[0007] Adding appropriate additives to the dispersion is an effective way to improve the conductivity of polymers.

[0008] Polyethylene glycol and its derivatives, and polyglycerol are used in the prior art, and their main function is to increase the breakdown voltage.

[0009] For example, the Chinese invention patent with publication number CN103429796A discloses using polyglycerol to reduce the ESR of a capacitor containing PEDOT / PSS as a solid electrolyte, but the improvement in capacity is not obvious. Summary of the invention

[0010] The purpose of the present invention is to overcome the problems of low capacitance and large ESR of solid electrolytic capacitors in the prior art.

[0011] In order to solve the above problems, the present invention provides a dispersion for aluminum electrolytic capacitors and an aluminum electrolytic capacitor prepared by using the dispersion.

[0012] The technical solution adopted by the present invention to solve the above technical problems is as follows:

[0013] Provided is a dispersion for aluminum electrolytic capacitors, comprising a dispersant, and a conductive polymer and an additive dispersed in the dispersant, wherein the additive is selected from one or more compounds represented by the following structural formula:

[0014] ;

[0015] The compound has at least one hydroxyl group and at least one ether group, wherein R1 and R2 are independently selected from sulfur-containing groups, carbon-containing groups, and hydrogen, and n is an integer of 1-10.

[0016] When n is 1-10, the water solubility of the dispersant is better. If n>10, the water solubility of the dispersant will deteriorate, affecting the overall performance of the capacitor.

[0017] Preferably, n is an integer of 1-5.

[0018] Furthermore, R1 and R2 are independently selected from sulfonate, sulfate, carbonyl, hydroxyacetone, glycerol, propylene glycol, hydrogen, and alkyl.

[0019] Furthermore, at least one of R1 and R2 is selected from hydroxyacetone, glycerol and propylene glycol.

[0020] R1 or R2 carries a hydroxyl group or both ends carry a hydroxyl group. The compound shown in structural formula I has both an ether bond and a hydroxyl group, which can greatly improve the bonding tightness between the conductive polymer and the dielectric oxide layer, which is extremely beneficial for increasing the capacity of the capacitor and reducing the ESR value.

[0021] Furthermore, the additive is selected from one or more of the following compounds 1 to 12:

[0022] .

[0023] Furthermore, relative to the total mass of the dispersion, the content of the additive is 0.01%-10%, and more preferably the content of the additive is 0.1%-5%.

[0024] When the content of the additive is too high, the viscosity of the dispersion will increase, affecting the impregnation effect and adversely affecting the performance of the capacitor; and when the content of the compound shown in structural formula I is too low, it will not play a significant role in improving the performance.

[0025] Furthermore, the conductive polymer is selected from one or more of polythiophene, polypyrrole, polyaniline, and derivatives thereof.

[0026] Polythiophene and its derivatives are preferred, and poly(3,4-ethylenedioxythiophene) is more preferred.

[0027] Furthermore, the dispersant is selected from an organic solvent and / or water, and the dispersant is preferably water.

[0028] The dispersion can be prepared by a conventionally known method.

[0029] The present invention also provides an aluminum electrolytic capacitor, which comprises: 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, wherein the solid electrolyte layer is prepared from the above dispersion.

[0030] The present invention provides a dispersion for aluminum electrolytic capacitors and an aluminum electrolytic capacitor, which have the following beneficial effects:

[0031] (1) The dispersion for aluminum electrolytic capacitors of the present invention uses the compound represented by structural formula I having a polyhydroxy ether structure as an additive to increase the capacitance of the aluminum electrolytic capacitor and reduce the ESR value. This is mainly because the polyhydroxy structure can promote the cross-linking between the conductive polymers and improve the electrolytic layer and dielectric layer Al generated by the conductive polymer. 2 O 3 The bonding tightness of the film increases the capacity extraction rate of the aluminum electrolytic capacitor and reduces the loss value and equivalent resistance of the aluminum electrolytic capacitor.

[0032] (2) In the dispersion for aluminum electrolytic capacitors of the present invention, the compound represented by the structural formula with 1≤n≤10 can be better dissolved in the dispersion without destroying the dispersion system, so that the dispersion will not increase in viscosity or gel. DETAILED DESCRIPTION

[0033] The technical solution of the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0034] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the protection scope of the present invention.

[0035] The core package used in the preparation of the electrolytic capacitor of the present invention is a winding core package with a specification of 16V1000 and a size of 10*13.

[0036] Example 1

[0037] This example is used to illustrate the preparation method of the aluminum electrolytic capacitor dispersion disclosed in the present invention, and the aluminum electrolytic capacitor prepared by using the dispersion.

[0038] 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, and a magnetic stirrer was used to stir at room temperature for 6 h, and then homogenized by a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0039] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0040] Example 2

[0041] As shown in Table 1, compared with Example 1, the only difference of this example is that the mass fraction of compound 1 is 0.1% of the total amount of the mixed solution, and other parameters and methods are the same as those of Example 1.

[0042] The details are as follows:

[0043] Compound 1 was added to PEDOT / PSS, with the mass fraction of compound 1 being 0.1% of the total amount of the mixed solution. A magnetic stirrer was used to stir the mixture at room temperature for 6 h, and then the mixture was homogenized by a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0044] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0045] Example 3

[0046] As shown in Table 1, compared with Example 1, the only difference of this example is that the mass fraction of compound 1 is 3% of the total amount of the mixed solution, and other parameters and methods are the same as those of Example 1.

[0047] The details are as follows:

[0048] Compound 1 was added to PEDOT / PSS, with the mass fraction of compound 1 being 3% of the total amount of the mixed solution. A magnetic stirrer was used to stir the mixture at room temperature for 6 h, and then the mixture was homogenized by a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0049] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0050] Example 4

[0051] As shown in Table 1, compared with Example 1, the only difference of this example is that the mass fraction of compound 1 is 0.01% of the total amount of the mixed solution, and other parameters and methods are the same as those of Example 1.

[0052] The details are as follows:

[0053] Compound 1 was added to PEDOT / PSS, with the mass fraction of compound 1 being 0.01% of the total amount of the mixed solution. A magnetic stirrer was used to stir the mixture at room temperature for 6 h, and then the mixture was homogenized by a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0054] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0055] Example 5

[0056] As shown in Table 1, compared with Example 1, the only difference of this example is that the mass fraction of compound 1 is 10% of the total amount of the mixed solution, and other parameters and methods are the same as those of Example 1.

[0057] The details are as follows:

[0058] Compound 1 was added to PEDOT / PSS, with the mass fraction of compound 1 being 10% of the total amount of the mixed solution. A magnetic stirrer was used to stir the mixture at room temperature for 6 h, and then the mixture was homogenized by a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0059] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0060] Comparative Example 1

[0061] As shown in Table 1, compared with Example 1, the only difference of this Example is that Compound 1 is not added, and other parameters and methods are the same as those of Example 1.

[0062] The details are as follows:

[0063] The PEDOT / PSS was stirred at room temperature for 6 h using a magnetic stirrer, and then homogenized using a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0064] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0065] Comparative Example 2

[0066] As shown in Table 1, compared with Example 1, the only difference of this example is that Compound 1 is replaced by glycerol, and other parameters and methods are the same as those of Example 1.

[0067] The details are as follows:

[0068] Glycerol was added to PEDOT / PSS, as shown in Table 1, the mass fraction of glycerol was 5% of the total amount of the mixed solution, a magnetic stirrer was used to stir at room temperature for 6 h, and then homogenized by a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0069] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0070] Comparative Example 3

[0071] As shown in Table 1, compared with Example 1, the only difference of this example is that Compound 1 is replaced by polyethylene glycol 400, and other parameters and methods are the same as those of Example 1.

[0072] The details are as follows:

[0073] Polyethylene glycol 400 was added to PEDOT / PSS, as shown in Table 1, the mass fraction of polyethylene glycol 400 was 5% of the total amount of the mixed solution, a magnetic stirrer was used to stir at room temperature for 6 h, and then homogenized by a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0074] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0075] Example 6

[0076] As shown in Table 1, compared with Example 1, the only difference of this example is that Compound 1 is replaced by Compound 2, and the mass fraction of Compound 2 is 3% of the total amount of the mixed solution. Other parameters and methods are the same as those of Example 1.

[0077] The details are as follows:

[0078] Compound 2 was added to PEDOT / PSS, with the mass fraction of compound 2 being 3% of the total amount of the mixed solution. A magnetic stirrer was used to stir the mixture at room temperature for 6 h, and then the mixture was homogenized by a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0079] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0080] Example 7

[0081] As shown in Table 1, compared with Example 1, the only difference of this example is that Compound 1 is replaced by Compound 3, the mass fraction of Compound 3 is 2% of the total amount of the mixed solution, and other parameters and methods are the same as those of Example 1.

[0082] The details are as follows:

[0083] Compound 3 was added to PEDOT / PSS, with the mass fraction of compound 3 being 2% of the total amount of the mixed solution. A magnetic stirrer was used to stir the mixture at room temperature for 6 h, and then the mixture was homogenized by a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0084] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0085] Example 8

[0086] As shown in Table 1, compared with Example 1, the only difference of this example is that Compound 1 is replaced by Compound 5, the mass fraction of Compound 5 is 1% of the total amount of the mixed solution, and other parameters and methods are the same as those of Example 1.

[0087] The details are as follows:

[0088] Compound 5 was added to PEDOT / PSS, with the mass fraction of compound 5 being 1% of the total amount of the mixed solution. A magnetic stirrer was used to stir the mixture at room temperature for 6 h, and then the mixture was homogenized by a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0089] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0090] Example 9

[0091] As shown in Table 1, compared with Example 1, the only difference of this example is that Compound 1 is replaced by Compound 8, and the mass fraction of Compound 8 is 1% of the total amount of the mixed solution. Other parameters and methods are the same as those of Example 1.

[0092] The details are as follows:

[0093] Compound 8 was added to PEDOT / PSS, with the mass fraction of compound 8 being 1% of the total amount of the mixed solution. A magnetic stirrer was used to stir the mixture at room temperature for 6 h, and then the mixture was homogenized by a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0094] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0095] Example 10

[0096] As shown in Table 1, compared with Example 1, the only difference of this Example is that Compound 1 is replaced by Compound 4, and other parameters and methods are the same as Example 1.

[0097] The details are as follows:

[0098] Compound 4 was added to PEDOT / PSS, with the mass fraction of compound 4 being 5% of the total amount of the mixed solution. A magnetic stirrer was used to stir the mixture at room temperature for 6 h, and then the mixture was homogenized by a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0099] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0100] Embodiment 11

[0101] As shown in Table 1, compared with Example 1, the only difference of this example is that Compound 1 is replaced by Compound 6, and other parameters and methods are the same as those of Example 1.

[0102] The details are as follows:

[0103] Compound 6 was added to PEDOT / PSS, with the mass fraction of compound 6 being 5% of the total amount of the mixed solution. A magnetic stirrer was used to stir the mixture at room temperature for 6 h, and then the mixture was homogenized by a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0104] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0105] Example 12

[0106] As shown in Table 1, compared with Example 1, the only difference of this example is that Compound 1 is replaced by Compound 7, and other parameters and methods are the same as those of Example 1.

[0107] The details are as follows:

[0108] Compound 7 was added to PEDOT / PSS, with the mass fraction of compound 7 being 5% of the total amount of the mixed solution. A magnetic stirrer was used to stir the mixture at room temperature for 6 h, and then the mixture was homogenized by a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0109] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0110] Example 13

[0111] As shown in Table 1, compared with Example 1, the only difference of this example is that Compound 1 is replaced by Compound 9, and other parameters and methods are the same as those of Example 1.

[0112] The details are as follows:

[0113] Compound 9 was added to PEDOT / PSS, with the mass fraction of compound 9 being 5% of the total amount of the mixed solution. A magnetic stirrer was used to stir at room temperature for 6 h, and then the mixture was homogenized by a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0114] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0115] Embodiment 14

[0116] As shown in Table 1, compared with Example 1, the only difference of this example is that Compound 1 is replaced by Compound 10, and other parameters and methods are the same as those of Example 1.

[0117] The details are as follows:

[0118] Compound 10 was added to PEDOT / PSS, with the mass fraction of compound 10 being 5% of the total amount of the mixed solution. A magnetic stirrer was used to stir at room temperature for 6 h, and then the mixture was homogenized by a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0119] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0120] Embodiment 15

[0121] As shown in Table 1, compared with Example 1, the only difference of this example is that Compound 1 is replaced by Compound 11, and other parameters and methods are the same as those of Example 1.

[0122] The details are as follows:

[0123] Compound 11 was added to PEDOT / PSS, with the mass fraction of compound 11 being 5% of the total amount of the mixed solution. The mixture was stirred at room temperature for 6 h using a magnetic stirrer, and then homogenized using a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0124] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0125] Example 16

[0126] As shown in Table 1, compared with Example 1, the only difference of this example is that Compound 1 is replaced by Compound 12, and other parameters and methods are the same as those of Example 1.

[0127] The details are as follows:

[0128] Compound 12 was added to PEDOT / PSS, with the mass fraction of compound 12 being 5% of the total amount of the mixed solution. A magnetic stirrer was used to stir at room temperature for 6 h, and then the mixture was homogenized by a homogenizer to obtain the aluminum electrolytic capacitor dispersion of the present invention.

[0129] The electrolytic capacitor core package was immersed in the aluminum electrolytic capacitor dispersion prepared in this example under negative pressure for 30 min and dried, and the above steps were repeated 3 times, and then the aluminum electrolytic capacitor was assembled after sealing.

[0130] The electrolytic capacitors prepared in Examples 1-16 and Comparative Examples 1-3 were subjected to performance tests: the electrostatic capacitance and loss value of the capacitors at a frequency of 120 Hz and the equivalent resistance at a frequency of 100 kHz were tested using an automatic electronic component analyzer.

[0131] Table 1 Types and contents of compounds in the dispersions of Examples 1-16 and Comparative Examples 1-3

[0132] Example / Comparative Example additive Quality score Example 1 Compound 1 5% Example 2 Compound 1 0.1% Example 3 Compound 1 3% Example 4 Compound 1 0.01% Example 5 Compound 1 10% Comparative Example 1 - - Comparative Example 2 glycerin 5% Comparative Example 3 Polyethylene glycol 400 5% Example 6 Compound 2 3% Example 7 Compound 3 2% Example 8 Compound 5 1% Example 9 Compound 8 1% Example 10 Compound 4 5% Embodiment 11 Compound 6 5% Example 12 Compound 7 5% Example 13 Compound 9 5% Embodiment 14 Compound 10 5% Embodiment 15 Compound 11 5% Example 16 Compound 12 5% ;

[0133] The test results of the above embodiments and comparative examples are shown in Table 2 below:

[0134] Table 2 Performance test of electrolytic capacitors prepared in Examples 1-16 and Comparative Examples 1-3

[0135] Example Cap (µF) DF (%) ESR (mΩ) Example 1 1051 2.18 6.11 Example 2 1040 2.53 6.78 Example 3 1048 2.21 6.24 Example 4 1021 2.98 6.97 Example 5 1039 3.01 7.02 Comparative Example 1 962 5.89 10.18 Comparative Example 2 1001 3.56 8.59 Comparative Example 3 1010 3.48. 8.34 Example 6 1046 2.37 6.56 Example 7 1053 2.23 6.45 Example 8 1039 2.45 6.78 Example 9 1035 2.47 6.91 Example 10 1049 2.23 6.37 Embodiment 11 1050 2.31 6.47 Example 12 1052 2.19 6.32 Example 13 1056 2.21 6.18 Embodiment 14 1049 2.31 6.45 Embodiment 15 1039 2.45 6.67 Example 16 1042 2.49 6.31 ;

[0136] It can be seen from the data in Table 2 that the electrolytic capacitor prepared by the dispersion for aluminum electrolytic capacitors of the present invention has an electrostatic capacitance (Cap) ≥ 1021µF, a capacitance loss value (DF) ≤ 3.01%, and an equivalent resistance (ESR) ≤ 7.02mΩ. The electrolytic capacitor of the present invention has a higher electrostatic capacitance, lower capacitance loss value and equivalent resistance.

[0137] It can be seen from the test results of Examples 1-5 in Table 2 that the content of Compound 1 in the dispersion is closely related to the improvement of the conductive properties of the electrolytic capacitor.

[0138] When the content of compound 1 is between 0.1% and 5%, the performance of the electrolytic capacitor prepared by its dispersion is significantly improved; when the content of compound 1 is low, the dispersion has a weak adsorption effect on the aluminum oxide film and cannot significantly improve the performance of the aluminum electrolytic capacitor; when the content of compound 1 is high, it will cause the viscosity of the dispersion to increase, affecting the impregnation effect and affecting the performance of the capacitor.

[0139] It can be seen from the test results of Comparative Examples 1-3 in Table 2 that, compared with the prior art, the additive of the present invention can improve the capacity extraction rate of the aluminum electrolytic capacitor, and reduce the loss value and equivalent resistance of the aluminum electrolytic capacitor, thereby greatly improving the conductive performance and stability of the aluminum electrolytic capacitor.

[0140] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A dispersion for aluminum electrolytic capacitors, It is characterized in that It comprises a dispersant, and a conductive polymer and an additive dispersed in the dispersant, wherein the additive is selected from one or more compounds represented by the following structural formula: The compound has at least one hydroxyl group and at least one ether group, wherein R1 and R2 are independently selected from sulfur-containing groups, carbon-containing groups, and hydrogen, and n is an integer of 1-10; R1 and R2 are independently selected from sulfonate, sulfate, carbonyl, hydroxyacetone, glycerol, propylene glycol, hydrogen, and alkyl; At least one of R1 and R2 is selected from hydroxyacetone, glycerol, and propylene glycol; The content of the additive is 0.01%-10% relative to the total mass of the dispersion.

2. The dispersion according to claim 1, It is characterized in that The additive is selected from one or more of the following compounds 1 to 12:

3. The dispersion according to any one of claims 1 to 2, It is characterized in that The conductive polymer is selected from one or more of polythiophene, polypyrrole, polyaniline, and derivatives thereof.

4. The dispersion according to claim 1, It is characterized in that The dispersant is selected from organic solvents and / or water.

5. An aluminum electrolytic capacitor, include: An anode body, a cathode body, a separator and a solid electrolyte layer covering at least a portion of the dielectric layer having a dielectric layer on the surface, characterized in that the solid electrolyte layer is prepared from the dispersion according to any one of claims 1 to 4.

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