阅读说明：本技术 一种基于pedot：snc的固态铝电解电容器及其制备方法 (A PEDOT-based: SNC solid aluminum electrolytic capacitor and preparation method thereof ) 是由 胡少强 刘一民 刘晓明 潘振炎 于 2021-06-11 设计创作，主要内容包括：一种基于PEDOT：SNC的固态铝电解电容器,包括阳极箔和阴极箔卷绕成的芯包,阳极箔和阴极箔之间形成有高分子导电聚合物薄膜,高分子导电聚合物薄膜包括PEDOT：SNC薄膜；所述PEDOT：SNC的重量比为1:2-2:1。在本发明中,通过硫酸化纳米纤维素(SNC)作为分散剂,通过原位聚合制备了PEDOT：SNC分散体,烘干后得到高分子导电聚合物。硫酸化纳米纤维素上的硫酸根基团具有出色的电负性和纳米纤维素的胶体稳定性,因此获得的PEDOT：SNC分散体显示出了高稳定性,并具有良好的再分散性。(A PEDOT-based: the SNC solid aluminum electrolytic capacitor comprises a core package formed by winding an anode foil and a cathode foil, wherein a high-molecular conductive polymer film is formed between the anode foil and the cathode foil, and comprises PEDOT: a SNC thin film; the PEDOT: the weight ratio of SNC is 1:2-2: 1. In the present invention, PEDOT is prepared by in situ polymerization by Sulfated Nanocellulose (SNC) as a dispersant: and (4) drying the SNC dispersion to obtain the high-molecular conductive polymer. The sulfate groups on the sulfated nanocellulose have excellent electronegativity and colloidal stability of nanocellulose, thus obtaining PEDOT: SNC dispersions show high stability and have good redispersibility.)

1. A PEDOT-based: SNC's solid-state aluminum electrolytic capacitor, including the core package of anode foil and negative pole foil coiling, be formed with the polymer film that conducts between anode foil and the negative pole foil, its characterized in that: the high-molecular conductive polymer film comprises PEDOT: a SNC thin film; the PEDOT: the weight ratio of SNC is 1:2-2: 1.

2. The PEDOT-based according to claim 1: the SNC solid aluminum electrolytic capacitor is characterized in that: the PEDOT: the SNC film is doped with carbon nanotubes, and the doping weight of the carbon nanotubes is 10-40% of the weight of the SNC.

3. A PEDOT-based polymer according to claim 1 or claim 2: the preparation method of the SNC solid aluminum electrolytic capacitor is characterized by comprising the following steps: comprises the following steps of (a) carrying out,

1) preparing sulfated nanocellulose;

2) adding an EDOT monomer into the sulfated nanocellulose aqueous dispersion prepared in the step 1), and uniformly dispersing;

3) core wrap impregnation of the dispersion obtained in the step 2);

4) impregnating the core wrap in the step 3) with a mixed solution of an oxidant and ammonium persulfate;

5) polymerization was carried out to form PEDOT: a high molecular conductive polymer film of SNC.

4. The PEDOT-based according to claim 3: the preparation method of the SNC solid aluminum electrolytic capacitor is characterized by comprising the following steps: preparation of the sulfated nanocellulose; adding sulfamic acid into DMF, mixing uniformly, adding cellulose, and then carrying out heating reaction;

filtering and dialyzing to remove impurities, and adding filter residues into the dispersion liquid;

thirdly, centrifugally dispersing uniformly by using a disperser to obtain the sulfated nanocellulose aqueous dispersion.

5. The PEDOT-based: the preparation method of the SNC solid aluminum electrolytic capacitor is characterized by comprising the following steps: the cellulose in the step I is pine pulp, the heating reaction temperature is 80-120 ℃, and the time is 2-4 hours.

6. The PEDOT-based according to claim 3: the preparation method of the SNC solid aluminum electrolytic capacitor is characterized by comprising the following steps: the impregnation in the step 3) is multiple impregnation, and the multiple impregnation comprises first impregnation and second impregnation; the first impregnation time is 2 minutes, and the temperature is normal temperature; directly drying at the temperature of 100-150 ℃ for 20-40 minutes after the first impregnation is finished; the second impregnation is performed in the same way as the first impregnation.

7. A PEDOT-based polymer according to claim 1 or claim 2: the preparation method of the SNC solid aluminum electrolytic capacitor is characterized by comprising the following steps: comprises the following steps of (a) carrying out,

1) preparing sulfated nanocellulose;

2) adding an EDOT monomer into the sulfated nanocellulose aqueous dispersion prepared in the step 1), and uniformly dispersing;

3) adding an oxidant and ammonium persulfate into the dispersion liquid in the step 2) to carry out polymerization reaction;

4) after the polymerization reaction in the step 3) is finished, removing impurities to obtain PEDOT: a dispersion of SNC;

5) core wrap impregnation of the dispersion obtained in the step 4); after drying, PEDOT was formed on the core package: a high molecular conductive polymer film of SNC.

8. The PEDOT-based according to claim 6: the preparation method of the SNC solid aluminum electrolytic capacitor is characterized by comprising the following steps: the oxidant is FeCl₃Mass ratio of ammonium persulfate to EDOT and FeCl₃The mass ratio to EDOT was 2 and 0.06, respectively.

Technical Field

The invention relates to a solid-state aluminum electrolytic capacitor, in particular to a solid-state aluminum electrolytic capacitor based on PEDOT: SNC solid aluminum electrolytic capacitor and preparation method thereof.

Background

The anode of the aluminum electrolytic capacitor is made of aluminum metal, a plurality of corrosion pits are formed on the surface of the anode foil, and a dielectric oxide film, namely an aluminum oxide film, is formed on the surface of the anode foil. The conductive electrolyte in contact with the oxide film plays a role of a true cathode in the electrolytic capacitor. As the true cathode of the capacitor, the quality of the electrolyte greatly affects the electrical performance of the aluminum electrolytic capacitor.

In order to achieve a large capacity of the aluminum electrolytic capacitor, an electrolytic paper is sandwiched between an anode foil and a cathode foil and wound together to form a core package; the solid aluminum electrolytic capacitor has conductive polymer adsorbed onto electrolytic paper.

There are two forms of forming the high molecular conductive polymer on the core cladding in the solid aluminum electrolytic capacitor. Firstly, the core wrap is impregnated with a high-molecular conductive polymer monomer and then polymerized under the action of an oxidant; this way impurities are introduced making the removal of impurities very cumbersome. Secondly, the core wrap is not easily impregnated into the core wrap due to the high viscosity of the general high molecular conductive polymer dispersion liquid, which requires to reduce the concentration of the high molecular conductive polymer dispersion liquid, so that the amount of the high molecular conductive polymer impregnated into the core wrap is reduced, and the holes of the high molecular conductive polymer in the core wrap are too many, thereby affecting the cycle performance of the solid aluminum electrolytic capacitor.

Patent 202011435148X, discloses a novel solid-state aluminum electrolytic capacitor and a method for making the same; PSS, namely PEDOT, is adopted as a solid electrolyte, the viscosity of the high-molecular conductive polymer is reduced through modification of polyallyl glycidyl ether, however, the existence of p-toluenesulfonic acid still influences the conductivity of the high-molecular conductive polymer, and the p-toluenesulfonic acid does not help the dispersion stability of the PEDOT, so that the PEDOT-containing solid electrolyte cannot meet the requirements in products with high electric capacity and high electrical performance.

Disclosure of Invention

The technical problem to be solved by the invention is to overcome the defects of the prior art, and provide a high-capacity and good-electrical-performance PEDOT-based: SNC solid aluminum electrolytic capacitor and preparation method thereof.

In order to solve the technical problems, the technical scheme provided by the invention is as follows: a PEDOT-based: the SNC solid aluminum electrolytic capacitor comprises a core package formed by winding an anode foil and a cathode foil, wherein a high-molecular conductive polymer film is formed between the anode foil and the cathode foil, and the high-molecular conductive polymer film comprises PEDOT: a SNC thin film; the PEDOT: the weight ratio of SNC is 1:2-2: 1.

The aforementioned PEDOT-based: SNC, preferably, the PEDOT: the SNC film is doped with carbon nanotubes, and the doping weight of the carbon nanotubes is 10-40% of the weight of the SNC.

A PEDOT-based: the preparation method of the SNC solid aluminum electrolytic capacitor comprises the following steps,

1) preparing sulfated nanocellulose;

2) adding an EDOT monomer into the sulfated nanocellulose aqueous dispersion prepared in the step 1), and uniformly dispersing;

3) core wrap impregnation of the dispersion obtained in the step 2);

4) impregnating the core wrap in the step 3) with a mixed solution of an oxidant and ammonium persulfate;

5) polymerization was carried out to form PEDOT: a high molecular conductive polymer film of SNC.

The aforementioned PEDOT-based: a method for producing a solid aluminum electrolytic capacitor of SNC, preferably, production of said sulfated nanocellulose; adding sulfamic acid into DMF, mixing uniformly, adding cellulose, and then carrying out heating reaction;

filtering and dialyzing to remove impurities, and adding filter residues into the dispersion liquid;

thirdly, centrifugally dispersing uniformly by using a disperser to obtain the sulfated nanocellulose aqueous dispersion.

The aforementioned PEDOT-based: the preparation method of the SNC solid aluminum electrolytic capacitor is preferable, the cellulose in the step (i) is pine pulp, the heating reaction temperature is 80-120 ℃, and the time is 2-4 hours.

The aforementioned PEDOT-based: in the preparation method of the SNC solid aluminum electrolytic capacitor, preferably, the impregnation in the step 3) is multiple impregnation, and the multiple impregnation includes first impregnation and second impregnation; the first impregnation time is 2 minutes, and the temperature is normal temperature; directly drying at the temperature of 100-150 ℃ for 20-40 minutes after the first impregnation is finished; the second impregnation is performed in the same way as the first impregnation.

The invention also provides a method according to claim 1 or claim 2 based on PEDOT: the preparation method of the SNC solid aluminum electrolytic capacitor comprises the following steps,

1) preparing sulfated nanocellulose;

2) adding an EDOT monomer into the sulfated nanocellulose aqueous dispersion prepared in the step 1), and uniformly dispersing;

3) adding an oxidant and ammonium persulfate into the dispersion liquid in the step 2) to carry out polymerization reaction;

4) after the polymerization reaction in the step 3) is finished, removing impurities to obtain PEDOT: a dispersion of SNC;

5) core wrap impregnation of the dispersion obtained in the step 4); after drying, PEDOT was formed on the core package: a high molecular conductive polymer film of SNC.

The aforementioned PEDOT-based: preferably, the oxidant is FeCl₃Mass ratio of ammonium persulfate to EDOT and FeCl₃The mass ratio to EDOT was 2 and 0.06, respectively.

Compared with the prior art, the invention has the advantages that: in the present invention, PEDOT is prepared by in situ polymerization by Sulfated Nanocellulose (SNC) as a dispersant: and (4) drying the SNC dispersion to obtain the high-molecular conductive polymer. The sulfate groups on the sulfated nanocellulose have excellent electronegativity and colloidal stability of nanocellulose, thus obtaining PEDOT: SNC dispersions show controlled conductivity, high stability, have excellent stability, and have good redispersibility.

Core pack impregnation to PEDOT: SNC dispersion, due to PEDOT: the SNC has good dispersibility, so that a high-molecular conductive polymer is easily formed in the deep part of the core bag, and the electrostatic capacity of the capacitor is increased; meanwhile, because PEDOT: the stability of SNC enables the capacitor to obtain good electrical performance.

Detailed Description

In order to facilitate an understanding of the present invention, the present invention will be described more fully and in detail with reference to the preferred embodiments, but the scope of the present invention is not limited to the specific embodiments described below.

It should be particularly noted that when an element is referred to as being "fixed to, connected to or communicated with" another element, it can be directly fixed to, connected to or communicated with the other element or indirectly fixed to, connected to or communicated with the other element through other intermediate connecting components.

Unless otherwise defined, all terms of art used hereinafter have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention.

Example 1

The present embodiment provides a method for manufacturing a chip based on PEDOT: the SNC solid aluminum electrolytic capacitor comprises a core package formed by winding an anode foil, electrolytic paper and a cathode foil, wherein a high-molecular conductive polymer film is formed between the anode foil and the cathode foil, and comprises PEDOT: a SNC thin film; PEDOT: the weight ratio of SNC is 1: 1.

In this example, the preparation of sulfated nanocellulose; adding sulfamic acid into DMF, mixing uniformly, adding cellulose, and then carrying out heating reaction; the cellulose is pine pulp, and the heating reaction temperature is 80-120 deg.C and the reaction time is 2-4 hr.

Filtering and dialyzing to remove impurities, and adding filter residues into the dispersion liquid;

thirdly, centrifugally dispersing uniformly by using a disperser to obtain the sulfated nanocellulose aqueous dispersion; the rotation speed of the disperser in this example was set at 10,000rpm and the centrifugation time was 30 minutes.

In this embodiment, the method of forming the high molecular conductive polymer on the core package is to prepare a dispersion of the high molecular conductive polymer and then impregnate the core package with the dispersion, which is advantageous in that the core package does not need to be subjected to impurity removal treatment.

In this embodiment, the method for forming the high molecular conductive polymer on the core package includes the following steps: 1) adding an EDOT monomer into the sulfated nanocellulose aqueous dispersion, and uniformly dispersing; the aqueous dispersion of sulfated nanocellulose was an aqueous solution with a SNC concentration of 0.5% by weight. In this embodiment, the solvent used as the dispersion may be an alcohol or an ether solvent.

2) Adding an oxidant and ammonium persulfate into the dispersion liquid obtained in the step 1) to carry out polymerization reaction; the oxidant being FeCl₃Mass ratio of ammonium persulfate to EDOT and FeCl₃The mass ratio to EDOT was 2 and 0.06, respectively.

3) After the polymerization reaction in the step 2) is finished, removing impurities to obtain PEDOT: a dispersion of SNC;

4) core wrap impregnation of the dispersion obtained in the step 3); after drying, PEDOT was formed on the core package: a high molecular conductive polymer film of SNC. The impregnation is multiple impregnation, and the multiple impregnation comprises first impregnation and second impregnation; the first impregnation time is 2 minutes, and the temperature is normal temperature; directly drying at the temperature of 100-150 ℃ for 20-40 minutes after the first impregnation is finished; the second impregnation is performed in the same way as the first impregnation.

In this example, a large number of active hydroxyl groups are present in the cellulose prepared from pine pulp, so that the desired groups can be introduced into the cellulose chains, in this example, sulfate groups are introduced into the cellulose chains, and the sulfate groups are negatively charged, and the negatively charged sulfate groups repel each other on the cellulose chains, thus providing good colloidal stability to the cellulose.

In this example, the EDOT monomer was first dispersed in the nanofibers. After the oxidant was added to the system, EDOT monomer was polymerized. Due to the strong electrostatic attraction between positively charged PEDOT and negatively charged SNC, they bind tightly to form PEDOT: a SNC complex. In FeCl₃And EDOT monomer starts to polymerize under the action of ammonium persulfate, PEDOT chains formed by polymerization are positively charged, negatively charged groups on SNC act on the PEDOT chains through electrostatic attraction, and the PEDOT chains grow along the nanofiber template with sulfate groupsLong. Wrapping the high aspect ratio nanofiber on PEDOT to form PEDOT: SNC nanoparticles, the excess negatively charged nanofibers PEDOT: the stability of the SNC dispersion provides a guarantee.

In this example, PEDOT: SNC nanoparticles enable PEDOT: the SNC nano-particles are uniformly and stably dispersed in the dispersion liquid. At the time of core impregnation due to PEDOT: the SNC nano particles are uniformly dispersed, so that impregnation is smoother, the impregnation amount is more, and the electrostatic capacity of the solid aluminum electrolytic capacitor is improved. The form of the polymer conductive material impregnated into the core package is more uniform, so that the electrical performance of the solid aluminum electrolytic capacitor is improved.

In this example, PEDOT: the conductivity of the high molecular conductive polymer film formed by SNC is far higher than that of the traditional PEDOT: PSS formed conductive polymer film; this is mainly due to the fact that in PEDOT: PSS introduces an insulating PSS, and PSS surrounds PEDOT, leading to a loss of conductivity of the final polymeric conductive film. And PEDOT: SNC avoids this situation.

Comparative example 1

In the comparative example, the core was impregnated with PEDOT: the PSS dispersion was otherwise the same as in example 1. The capacity test, the internal resistance test and the capacity extraction test were performed on example 1 and comparative example 1, and the results are shown in the following table, from which it can be seen that the capacitor of example 1 has good electrical properties compared to the capacitor of comparative example 1.

Example 2

This example differs from example 1 in that in example 1 the core pack is impregnated with PEDOT: SNC dispersion, whereas in this example, the core pack was impregnated first with the aqueous dispersion of sulfated nanocellulose to which EDOT monomer was added, and then with the mixed solution of oxidant and ammonium persulfate; the core bag is subjected to polymerization reaction, the anodic oxide film is damaged to a certain extent due to the polymerization reaction on the core bag, but the core bag can be impregnated with more polymerized monomers, that is, the core bag can be impregnated with more EDOT, and meanwhile, the condition is more favorable for controlling the cost of manufacturers of the solid-state aluminum electrolytic capacitors, because the PEDOT: the cost price of SNC is relatively high. The preparation method of the solid-state aluminum electrolytic capacitor of the embodiment comprises the following steps:

1) preparing sulfated nanocellulose;

2) adding an EDOT monomer into the sulfated nanocellulose aqueous dispersion prepared in the step 1), and uniformly dispersing;

3) core wrap impregnation of the dispersion obtained in the step 2);

4) impregnating the core wrap in the step 3) with a mixed solution of an oxidant and ammonium persulfate;

5) polymerization was carried out to form PEDOT: a high molecular conductive polymer film of SNC.