CN117690728A

CN117690728A - Preparation method of anode foil based on aqueous binder and aluminum electrolytic capacitor

Info

Publication number: CN117690728A
Application number: CN202311760437.0A
Authority: CN
Inventors: 陈志斌; 张哲健; 田宁; 李明哲; 王立强; 王海丽
Original assignee: Xian Rare Metal Materials Research Institute Co Ltd
Current assignee: Xian Rare Metal Materials Research Institute Co Ltd
Priority date: 2023-12-20
Filing date: 2023-12-20
Publication date: 2024-03-12

Abstract

The disclosure relates to a preparation method of an anode foil based on an aqueous binder and an aluminum electrolytic capacitor, and relates to the technical field of aluminum electrolytic capacitors. The preparation method comprises the following steps: s1, obtaining a binder solution, wherein the mass ratio of deionized water to an aqueous binder is 1: (4-8%); obtaining dry aluminum powder with the particle size of 1-5 mu m; obtaining an aluminum foil matrix; s2, paving an aluminum powder layer with the thickness of 40-60 mu m on the upper surface of the aluminum foil substrate; spraying a binder solution on the aluminum powder layer, and drying; s3, turning over the aluminum foil matrix for 180 degrees, and repeating the step S2 to obtain the aluminum foil matrix with the double aluminum powder layers; s4, sintering the aluminum foil substrate with the double aluminum powder layers to obtain a sintered aluminum foil; and S5, carrying out water boiling treatment and formation treatment on the sintered aluminum foil to obtain the anode foil. The method provided by the disclosure avoids the use of organic solvents, is safe and environment-friendly, and reduces the solvent cost.

Description

Preparation method of anode foil based on aqueous binder and aluminum electrolytic capacitor

Technical Field

The disclosure relates to the technical field of aluminum electrolytic capacitors, in particular to a preparation method of an anode foil based on an aqueous binder and an aluminum electrolytic capacitor.

Background

The aluminum electrolytic capacitor is widely applied to the fields of automobile electronics, household appliances, industrial control and the like due to the advantages of small size, low cost, high specific capacitance and the like. With the rapid development of the electronic industry, the requirements of large capacity and small volume of the aluminum electrolytic capacitor are urgent, and the capacity of the aluminum electrolytic capacitor is mainly determined by the anode foil, so that the requirement of higher specific capacity is provided for the anode foil. At present, the anode foil of the aluminum electrolytic capacitor mainly adopts corrosion foil, but waste acid generated in the corrosion process has larger environmental protection pressure. In addition, a method of sintering a porous layer on the surface of an aluminum foil substrate instead of etching the etched foil has been developed in recent years. For example, chinese patents CN104919552B, CN102714098B, CN102804302A, CN110993347B, CN103688327A, CN110993348A, CN104409215a and CN111146005B disclose sintering a porous aluminum powder layer on an aluminum foil substrate to increase the specific surface area of the aluminum foil, thereby increasing the specific capacity of the aluminum foil. However, most of the solvents used in these patents are organic solvents such as terpineol, ethanol, xylene and methanol, which have great potential safety hazards to the environment and operators, and have high requirements on the safety of production equipment, waste treatment and solvent recovery, and the cost of solvent recovery and reuse is high.

It should be noted that the information disclosed in the above background section is only for enhancing understanding of the background of the present disclosure and thus may include information that does not constitute prior art known to those of ordinary skill in the art.

Disclosure of Invention

The purpose of the present disclosure is to overcome the shortcomings of the prior art, and provide a preparation method of an anode foil based on an aqueous binder and an aluminum electrolytic capacitor, so as to solve the problems of environmental pollution, difficult waste recovery and treatment and high cost caused by an organic solvent.

According to one aspect of the present disclosure, a method for preparing an aqueous binder-based anode foil comprises the steps of:

s1, obtaining a binder solution, wherein the mass ratio of deionized water to an aqueous binder in the binder solution is 1: (4-8%);

obtaining dry aluminum powder, wherein the particle size of the aluminum powder is 1-5 mu m;

obtaining an aluminum foil matrix;

s2, uniformly paving the aluminum powder on the upper surface of the aluminum foil matrix to form an aluminum powder layer; the laying thickness of the aluminum powder layer is 40-60 mu m;

spraying the binder solution on the aluminum powder layer, and drying;

s3, turning over the aluminum foil substrate for 180 degrees, and repeating the step S2 to obtain an aluminum foil substrate with double aluminum powder layers;

S4, sintering the aluminum foil substrate with the double aluminum powder layers to obtain a sintered aluminum foil;

and S5, sequentially carrying out water boiling treatment and formation treatment on the sintered aluminum foil to obtain the anode foil.

In one exemplary embodiment of the present disclosure, in step S1, the aqueous binder is one or more of polyvinyl alcohol, hydroxyethyl cellulose, polyvinylpyrrolidone, hydroxypropyl methylcellulose, and hydroxyethyl methylcellulose.

In an exemplary embodiment of the present disclosure, in step S1, the mass purity of the aluminum powder is greater than or equal to 99.95%.

In one exemplary embodiment of the present disclosure, in step S1, the aluminum particles in the aluminum powder are spherical in shape.

In an exemplary embodiment of the present disclosure, in step S2, the spraying of the aqueous binder onto the aluminum powder layer is spraying using a spray head; the distance between the end part of the spray head and the aluminum powder layer is 5-15 cm, and the moving speed of the spray head is 20-30 cm/min.

In one exemplary embodiment of the present disclosure, in step S4, the sintering is performed in a nitrogen, argon or vacuum atmosphere at a sintering temperature of: heating from room temperature to 300-380 ℃ at a heating rate of 1-10 ℃/min, and preserving heat for 1-5 h; heating to 420-460 ℃ at a heating rate of 1-10 ℃/min, and preserving heat for 1-6 h; heating to 620-650 ℃ at a heating rate of 1-10 ℃/min, and preserving heat for 0.5-10 h.

In an exemplary embodiment of the present disclosure, the water boiling process uses deionized water and is boiled at 95-100 ℃ for 10-15 min in step S5.

In one exemplary embodiment of the present disclosure, the aluminum foil substrate has a thickness of 20 to 60 μm in step S1.

In one exemplary embodiment of the present disclosure, a method of preparing an aqueous binder-based anode foil includes the steps of:

in step S1, dried aluminum powder is obtained: drying spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.95% in vacuum at 100 ℃ for 2h;

obtaining a binder solution: adding 4%M polyvinyl alcohol, 3%M hydroxyethyl cellulose and 1%M hydroxyethyl methylcellulose into M deionized water serving as a solvent, stirring at 75 ℃ for 1h, and cooling to 25 ℃;

obtaining an aluminum foil substrate with the thickness of 50 mu m;

in the step S2, aluminum powder is uniformly paved on the upper surface of an aluminum foil matrix to form an aluminum powder layer with the thickness of 60 mu m; spraying a binder solution on the aluminum powder layer, and drying at 100 ℃; the method comprises the steps of spraying binder solution by using a piezoelectric spray head, wherein the distance between the end part of the spray head and an aluminum powder layer is 10cm, and the moving speed of the spray head is 20cm/min;

In the step S3, turning over the aluminum foil substrate for 180 degrees, and repeating the step S2 to obtain an aluminum foil substrate with a double aluminum powder layer;

in step S4, sintering the aluminum foil substrate with the double aluminum powder layer; the sintering temperature of the sintering is as follows: heating from room temperature to 300 ℃ at a heating rate of 5 ℃/min, and preserving heat for 5 hours; heating to 420 ℃ at a heating rate of 5 ℃/min, and preserving heat for 6 hours; finally, heating to 640 ℃ at a heating rate of 5 ℃/min, preserving heat for 6 hours, and cooling along with a furnace after the heat preservation is finished to obtain a sintered aluminum foil; the sintering is performed in an argon atmosphere;

in the step S5, the sintered aluminum foil is boiled in deionized water at 100 ℃ for 15min, and is subjected to formation treatment under 520V formation voltage by adopting 100g/L boric acid solution; and cleaning with deionized water, and drying at 100 ℃ to obtain the anode foil.

According to another aspect of the present disclosure, there is provided an aluminum electrolytic capacitor including an anode foil prepared by the above-described method for preparing an anode foil based on an aqueous binder.

Preparing a binder solution by taking deionized water as a solvent, paving aluminum powder, spraying the binder solution, solidifying the aluminum powder on the upper surface and the lower surface of an aluminum foil substrate, and forming a porous layer on the surface of a sintered aluminum foil after sintering; after the sintered aluminum foil is subjected to water boiling treatment and formation treatment, the anode foil for the aluminum electrolytic capacitor meeting the use requirements of medium-high pressure environment is obtained. The method avoids the use of organic solvents, is safe and environment-friendly, and reduces the solvent cost. The deionized water and the aqueous binder are used for preparing the binder solution, the binder solution has low drying temperature, is easy to dry, does not discharge organic gas polluting the environment in the sintering process, has simple tail gas treatment, and has no residue after sintering. Meanwhile, the preparation method of the anode foil provided by the embodiment of the disclosure does not need to use various acid liquids used in the preparation process of the corrosion foil, does not generate waste acid, and is more environment-friendly.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the disclosure and together with the description, serve to explain the principles of the disclosure. It will be apparent to those of ordinary skill in the art that the drawings in the following description are merely examples of the disclosure and that other drawings may be derived from them without undue effort.

Fig. 1 is an SEM image of an anode foil prepared in example 1 in one embodiment of the present disclosure.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be embodied in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art.

Although relative terms such as "upper" and "lower" are used in this specification to describe the relative relationship of one component of an icon to another component, these terms are used in this specification for convenience only. It will be appreciated that if the device is turned upside down, the components recited as "up" will become "down".

The terms "a," "an," "the," and "multiple" are used to indicate the presence of one or more elements/components/etc.; the terms "comprising" and "having" are intended to be inclusive and mean that there may be additional elements/components/etc. in addition to the listed elements/components/etc.

The embodiment of the disclosure provides a preparation method of an anode foil based on an aqueous binder, which comprises the following steps: s1, obtaining a binder solution: in the binder solution, the mass ratio of deionized water to the aqueous binder is 1: (4-8%).

In one embodiment of the present disclosure, the aqueous binder may be one or more of polyvinyl alcohol, hydroxyethyl cellulose, polyvinylpyrrolidone, hydroxypropyl methylcellulose, and hydroxyethyl methylcellulose. That is, using deionized water of mass M as the solvent, an aqueous binder of 4%M, or 5% M, or 5.5% M, or 6%M, or 7%M, or 7.8% M, or 8%M may be added. It is understood that when the above-described plurality of aqueous binders are selected to be used in combination, the total mass of the various aqueous binders used in combination is 4 to 8% of the mass of deionized water as a solvent.

In one example, the mass ratio of deionized water to aqueous binder is 1: (4-8%), the aqueous binder can be added into deionized water with the temperature of 70-80 ℃ to be stirred for 0.5-1.5 h and then cooled to normal temperature. For example, the aqueous binder may be added to deionized water at 80 ℃ and stirred for 1h, or the aqueous binder may be added to deionized water at 75 ℃ and stirred for 1h, or the aqueous binder may be added to deionized water at 70 ℃ and stirred for 0.5h, or the aqueous binder may be added to deionized water at 70 ℃ and stirred for 1.5h. The normal temperature in this disclosure refers to 25 ℃. In this embodiment, the content of the aqueous binder in the aqueous binder solution is controlled so that the binder solution has a proper viscosity at normal temperature, is easily dried, and has no residue after sintering.

Obtaining dried aluminum powder: the particle size of the aluminum powder is 1-5 mu m, and the aluminum powder can be formed by mixing aluminum powder with various particle sizes in the range of 1-5 mu m. In one embodiment of the present disclosure, the mass purity of the aluminum powder is greater than or equal to 99.95%. Further, the aluminum particles in the aluminum powder are spherical in shape. The drying mode of the aluminum powder can be as follows: vacuum drying at 100deg.C. Thus, in the above-described embodiment, the introduction of impurities can be prevented by controlling the mass purity of the spherical aluminum powder. The aluminum powder can be well fluidity and is easier to pave by drying the aluminum powder and controlling the particle size range of the aluminum powder.

Obtaining an aluminum foil substrate: the thickness of the aluminum foil matrix may be, for example, 20 μm to 60 μm, and the final anode foil may be provided with suitable mechanical strength by selecting a suitable thickness of the aluminum foil matrix. For example, an aluminum foil substrate having a thickness of 20 μm, 30 μm, 40 μm, 50 μm or 60 μm may be used.

S2, uniformly paving the aluminum powder on the upper surface of the aluminum foil matrix to form an aluminum powder layer; the laying thickness of the aluminum powder layer is 40-60 mu m. According to the embodiment of the disclosure, the thickness of the aluminum powder layer is limited, so that the upper surface and the lower surface of the aluminum foil substrate after sintering are provided with porous layers, and the anode foil after formation treatment is ensured to have high specific capacity. The thickness of the porous layer is too small, and the specific capacity of the aluminum foil is low after the water boiling treatment and the formation treatment; the thickness of the porous layer is too large, and the aluminum foil has high hardness and is easy to break after the water boiling treatment and the formation treatment. The aluminum powder layer paving thickness provided by the embodiment can enable the prepared anode foil to have high specific capacity and proper hardness. For example, the aluminum powder layer may be laid to a thickness of 40 μm, 45 μm, 48 μm, 50 μm, 55 μm or 60 μm.

Spraying the binder solution onto the aluminum powder layer and drying at 100 ℃. In one embodiment of the disclosure, a piezoelectric spray nozzle can be used for spraying, the distance between the end part of the spray nozzle and the aluminum powder layer is 5-15 cm, and the moving speed of the spray nozzle is 20-30 cm/min, so that the content of the water-based adhesive in the aluminum powder is moderate, and the aluminum powder on the dried aluminum foil does not fall off. According to the embodiment of the disclosure, the aluminum powder layer is paved firstly, and then the binder solution is sprayed, so that slurry does not need to be prepared, the preparation process is simplified, and the forming speed is higher.

S3, turning the aluminum foil substrate by 180 degrees, and repeating the operation of the step S2, so that after the aluminum foil substrate is turned over, the original upper surface is changed into the lower surface, and the original lower surface is changed into the upper surface, thereby forming aluminum powder layers on both surfaces of the aluminum foil substrate, and obtaining the aluminum foil substrate with double aluminum powder layers.

And S4, sintering the aluminum foil substrate with the double aluminum powder layers to obtain the sintered aluminum foil. In one embodiment of the present disclosure, the sintering is performed in a nitrogen, argon or vacuum environment. In one example, the sintering temperature is the first stage: heating from room temperature to 300-380 ℃ at a heating rate of 1-10 ℃/min, and preserving heat for 1-5 h; and a second stage: heating to 420-460 ℃ at a heating rate of 1-10 ℃/min, and preserving heat for 1-6 h; and a third stage: heating to 620-650 ℃ at a heating rate of 1-10 ℃/min, and preserving heat for 0.5-10 h. Thus, the aqueous binder in the aluminum powder layer can be removed by the sintering in the first stage and the second stage, and the aqueous binder has no residue; and in the third stage, sintering the aluminum powder layer on the surface of the aluminum foil substrate into a porous layer to form the sintered aluminum foil.

In one embodiment of the present disclosure, the water boiling treatment is deionized water and water boiling is performed at 95-100 ℃ for 10-15 min. The deionized water is adopted for water boiling treatment, so that the introduction of impurities can be prevented, and hydrated alumina with proper thickness is formed on the surface of the aluminum foil by controlling the water boiling temperature and water boiling time, thereby being beneficial to subsequent formation treatment. For example, the cooking may be done at 95 ℃ (either 98 ℃ or 100 ℃) for 10min, 12min, 14min or 15min.

In one embodiment of the present disclosure, the formation treatment may employ a boric acid solution of 90 to 110g/L, and the sintered aluminum foil is treated at a formation voltage of 500 to 590V to form an aluminum oxide film. After the formation treatment, deionized water is adopted for cleaning, so that the introduction of impurities is avoided.

Preparing a binder solution by taking deionized water as a solvent, paving aluminum powder, spraying the binder solution and drying, solidifying the aluminum powder on the upper surface and the lower surface of an aluminum foil substrate, and forming a porous layer on the surface of a sintered aluminum foil after sintering; after the sintered aluminum foil is subjected to water boiling treatment and formation treatment, the anode foil for the aluminum electrolytic capacitor meeting the use requirements of medium-high pressure environment is obtained. The method provided by the disclosure avoids the use of organic solvents, is safe and environment-friendly, and reduces the solvent cost; the deionized water and the aqueous binder are used for preparing the binder solution, the binder solution has low drying temperature, is easy to dry, does not discharge organic gas polluting the environment in the sintering process, has simple tail gas treatment, and has no residue after sintering. Meanwhile, the preparation method of the anode foil provided by the embodiment of the disclosure does not need to use various acid liquids used in the preparation process of the corrosion foil, does not generate waste acid, and is more environment-friendly.

The method of preparing an anode foil based on an aqueous binder is further described below in connection with specific examples.

Comparative examples

1. Spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.99 percent, organic solvent terpineol, binder ethylcellulose and dispersant polyethylene glycol are mixed and stirred uniformly according to the mass ratio of 60:35:4:1, so as to obtain slurry.

2. And (3) coating the slurry obtained in the step (1) on the upper surface and the lower surface of the aluminum foil substrate in a double-sided symmetrical manner by adopting a scraper coating mode, and then drying in vacuum. Wherein the thickness of the aluminum foil substrate is 20 μm, the drying temperature is 100 ℃, and the thickness of the aluminum foil dried after the slurry is coated is 120 μm.

3. And (3) sintering the aluminum foil dried in the step (2) in a sintering furnace to obtain the sintered aluminum foil. The sintering process comprises the following steps: (1) Heating from room temperature to 300 ℃ at a heating rate of 10 ℃/min, and preserving heat for 5 hours; (2) Heating to 420 ℃ at a heating rate of 10 ℃/min, and preserving heat for 6 hours; (3) Heating to 620 ℃ at a heating rate of 10 ℃/min, preserving heat for 10h, and cooling with a furnace after the heat preservation is finished. And argon atmosphere is arranged in the sintering furnace in the sintering process.

4. And (3) carrying out water boiling treatment and formation treatment on the sintered aluminum foil obtained in the step (3), and cleaning and drying to obtain the anode foil for the aluminum electrolytic capacitor. The water boiling treatment adopts deionized water at 100 ℃ for 10min. The formation treatment adopts 100g/L boric acid solution, and the formation voltage is 520V. Deionized water is adopted in the cleaning process, and the drying temperature is 100 ℃.

The static specific capacity of the anode foil for aluminum electrolytic capacitor prepared in the comparative example was 0.89. Mu.F/cm ² 。

Example 1

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.99% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: deionized water with mass M is taken as a solvent, polyvinyl alcohol of 4%M is added, and the mixture is stirred for 1h at 75 ℃ and then cooled to 25 ℃. An aluminum foil substrate having a thickness of 20 μm was obtained.

2. Uniformly paving aluminum powder on the upper surface of an aluminum foil matrix to form an aluminum powder layer with the thickness of 50 mu m; spraying binder solution on the aluminum powder layer, and drying at 100 ℃. The spray adhesive solution adopts a piezoelectric spray head, the distance between the end part of the spray head and the aluminum powder layer is 5cm, and the moving speed of the spray head is 25cm/min.

3. Turning over the aluminum foil substrate for 180 degrees, and repeating the operation of the step 2 to obtain an aluminum foil substrate with double aluminum powder layers;

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a sintering furnace in argon atmosphere, and the sintering temperature is as follows: heating from room temperature to 300 ℃ at a heating rate of 10 ℃/min, and preserving heat for 5 hours; heating to 420 ℃ at a heating rate of 10 ℃/min, and preserving heat for 6 hours; and finally heating to 620 ℃ at a heating rate of 10 ℃/min, preserving heat for 10 hours, and cooling along with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

5. Boiling the sintered aluminum foil in deionized water at 100 ℃ for 10min, and adopting a boric acid solution of 100g/L to perform formation treatment under a formation voltage of 520V; and cleaning with deionized water, and drying at 100 ℃ to obtain the anode foil for the aluminum electrolytic capacitor.

Referring to fig. 1, which is a Scanning Electron Microscope (SEM) image of the anode foil prepared in this example, it can be seen that uniform porous layers were formed on the upper and lower surfaces of the aluminum foil substrate. The anode foil prepared in this example had a static specific capacity of 0.96. Mu.F/cm ² . Compared with the comparative example, the static specific capacity of the porous layer of the anode foil prepared by adopting the water-based binder is higher than that of the porous layer formed on the surface of the aluminum foil substrate by adopting the organic solvent to prepare the slurry on the premise of the same sintering, water boiling and formation treatment processes. The method for preparing the anode foil based on the aqueous binder is simple in preparation process and environment-friendly, and the static specific capacity of the obtained anode foil is higher or equal to that of the anode foil prepared by the existing method.

Example 2

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.95% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: deionized water with mass M is taken as a solvent, polyvinyl alcohol of 6%M is added, and the mixture is stirred for 1h at 75 ℃ and then cooled to 25 ℃. An aluminum foil substrate having a thickness of 30 μm was obtained.

2. Uniformly paving aluminum powder on the upper surface of an aluminum foil matrix to form an aluminum powder layer with the thickness of 60 mu m; spraying binder solution on the aluminum powder layer, and drying at 100 ℃. The spray adhesive solution adopts a piezoelectric spray head, the distance between the end part of the spray head and the aluminum powder layer is 10cm, and the moving speed of the spray head is 20cm/min.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a vacuum sintering furnace, and the sintering temperature is as follows: heating from room temperature to 340 ℃ at a heating rate of 1 ℃/min, and preserving heat for 3 hours; heating to 460 ℃ at a heating rate of 1 ℃/min, and preserving heat for 1h; finally heating to 640 ℃ at a heating rate of 1 ℃/min, preserving heat for 6 hours, and cooling along with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

5. Boiling the sintered aluminum foil in deionized water at 100 ℃ for 12min, and adopting a boric acid solution of 100g/L to perform formation treatment under a formation voltage of 520V; and cleaning with deionized water, and drying at 100 ℃ to obtain the anode foil for the aluminum electrolytic capacitor.

The static specific capacity of the anode foil for aluminum electrolytic capacitor prepared in this example was 1.16. Mu.F/cm ² The method comprises the steps of carrying out a first treatment on the surface of the SEM images of the anode foil prepared in this example were similar in structure to SEM images of the anode foil prepared in example 1.

Example 3

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.95% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: deionized water with mass M is taken as a solvent, polyvinyl alcohol of 8%M is added, and the mixture is stirred for 1h at 75 ℃ and then cooled to 25 ℃. An aluminum foil substrate having a thickness of 40 μm was obtained.

2. Uniformly paving aluminum powder on the upper surface of an aluminum foil matrix to form an aluminum powder layer with the thickness of 40 mu m; spraying binder solution on the aluminum powder layer, and drying at 100 ℃. The spray adhesive solution adopts a piezoelectric spray head, the distance between the end part of the spray head and the aluminum powder layer is 15cm, and the moving speed of the spray head is 30cm/min.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a sintering furnace in argon atmosphere, and the sintering temperature is as follows: heating from room temperature to 380 ℃ at a heating rate of 5 ℃/min, and preserving heat for 3 hours; heating to 440 ℃ at a heating rate of 5 ℃/min, and preserving heat for 4 hours; and finally, heating to 650 ℃ at a heating rate of 5 ℃/min, preserving heat for 5 hours, and cooling with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

5. Boiling the sintered aluminum foil in deionized water at 95 ℃ for 10min, and adopting a boric acid solution of 100g/L to perform formation treatment under a formation voltage of 520V; and cleaning with deionized water, and drying at 100 ℃ to obtain the anode foil for the aluminum electrolytic capacitor.

The static specific capacity of the anode foil for aluminum electrolytic capacitor prepared in this example was found to be 0.85. Mu.F/cm ² The method comprises the steps of carrying out a first treatment on the surface of the SEM images of the anode foil prepared in this example were similar in structure to SEM images of the anode foil prepared in example 1.

The aqueous binder in examples 1 to 3 may also be replaced with any one of hydroxyethyl cellulose, polyvinylpyrrolidone, hydroxypropyl methylcellulose and hydroxyethyl methylcellulose.

Example 4

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.95% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: deionized water of mass M is used as a solvent, polyvinyl alcohol of 2%M and hydroxyethyl cellulose of 2%M are added, and the mixture is stirred for 1h at 75 ℃ and then cooled to 25 ℃. An aluminum foil substrate having a thickness of 50 μm was obtained.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a vacuum sintering furnace, and the sintering temperature is as follows: heating from room temperature to 340 ℃ at a heating rate of 5 ℃/min, and preserving heat for 3 hours; heating to 420 ℃ at a heating rate of 5 ℃/min, and preserving heat for 4 hours; and finally, heating to 650 ℃ at a heating rate of 5 ℃/min, preserving heat for 2 hours, and cooling along with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

The static specific capacity of the anode foil for aluminum electrolytic capacitor prepared in this example was found to be 0.94. Mu.F/cm ² The method comprises the steps of carrying out a first treatment on the surface of the SEM images of the anode foil prepared in this example were similar in structure to SEM images of the anode foil prepared in example 1.

Example 5

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.95% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: deionized water of mass M is used as a solvent, polyvinyl alcohol of 2%M and hydroxyethyl cellulose of 4%M are added, and the mixture is stirred for 1h at 75 ℃ and then cooled to 25 ℃. An aluminum foil substrate having a thickness of 60 μm was obtained.

2. Uniformly paving aluminum powder on the upper surface of an aluminum foil matrix to form an aluminum powder layer with the thickness of 50 mu m; spraying binder solution on the aluminum powder layer, and drying at 100 ℃. The spray adhesive solution adopts a piezoelectric spray head, the distance between the end part of the spray head and the aluminum powder layer is 10cm, and the moving speed of the spray head is 25cm/min.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a sintering furnace in nitrogen atmosphere, and the sintering temperature is as follows: heating from room temperature to 300 ℃ at a heating rate of 5 ℃/min, and preserving heat for 5 hours; heating to 460 ℃ at a heating rate of 5 ℃/min, and preserving heat for 2 hours; finally heating to 640 ℃ at a heating rate of 5 ℃/min, preserving heat for 8 hours, and cooling along with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

5. Boiling the sintered aluminum foil in deionized water at 95 ℃ for 12min, and adopting a boric acid solution of 100g/L to perform formation treatment under a formation voltage of 520V; and cleaning with deionized water, and drying at 100 ℃ to obtain the anode foil for the aluminum electrolytic capacitor.

The static specific capacity of the anode foil for aluminum electrolytic capacitor prepared in this example was found to be 0.97. Mu.F/cm ² The method comprises the steps of carrying out a first treatment on the surface of the SEM images of the anode foil prepared in this example were similar in structure to SEM images of the anode foil prepared in example 1.

Example 6

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.99% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: deionized water of mass M is used as a solvent, polyvinyl alcohol of 2%M and hydroxyethyl cellulose of 6%M are added, and the mixture is stirred for 1h at 75 ℃ and then cooled to 25 ℃. An aluminum foil substrate having a thickness of 20 μm was obtained.

2. Uniformly paving aluminum powder on the upper surface of an aluminum foil matrix to form an aluminum powder layer with the thickness of 60 mu m; spraying binder solution on the aluminum powder layer, and drying at 100 ℃. The spray adhesive solution adopts a piezoelectric spray head, the distance between the end part of the spray head and the aluminum powder layer is 15cm, and the moving speed of the spray head is 20cm/min.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a vacuum sintering furnace, and the sintering temperature is as follows: heating from room temperature to 340 ℃ at a heating rate of 10 ℃/min, and preserving heat for 2 hours; heating to 420 ℃ at a heating rate of 10 ℃/min, and preserving heat for 4 hours; finally heating to 640 ℃ at a heating rate of 10 ℃/min, preserving heat for 4 hours, and cooling along with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

5. Boiling the sintered aluminum foil in deionized water at 95 ℃ for 15min, and adopting 90g/L boric acid solution to perform formation treatment under 550V formation voltage; and cleaning with deionized water, and drying at 100 ℃ to obtain the anode foil for the aluminum electrolytic capacitor.

The static specific capacity of the anode foil for aluminum electrolytic capacitor prepared in this example was 1.09. Mu.F/cm ² The method comprises the steps of carrying out a first treatment on the surface of the SEM images of the anode foil prepared in this example were similar in structure to SEM images of the anode foil prepared in example 1.

Example 7

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.99% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: deionized water of mass M is used as a solvent, polyvinyl alcohol of 4%M and hydroxyethyl cellulose of 2%M are added, and the mixture is stirred for 1h at 75 ℃ and then cooled to 25 ℃. An aluminum foil substrate having a thickness of 20 μm was obtained.

2. Uniformly paving aluminum powder on the upper surface of an aluminum foil matrix to form an aluminum powder layer with the thickness of 40 mu m; spraying binder solution on the aluminum powder layer, and drying at 100 ℃. The spray adhesive solution adopts a piezoelectric spray head, the distance between the end part of the spray head and the aluminum powder layer is 5cm, and the moving speed of the spray head is 30cm/min.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a sintering furnace in argon atmosphere, and the sintering temperature is as follows: heating from room temperature to 380 ℃ at a heating rate of 5 ℃/min, and preserving heat for 5 hours; heating to 440 ℃ at a heating rate of 5 ℃/min, and preserving heat for 6 hours; and finally, heating to 620 ℃ at a heating rate of 5 ℃/min, preserving heat for 6 hours, and cooling with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

The static specific capacity of the anode foil for aluminum electrolytic capacitor prepared in this example was found to be 0.83. Mu.F/cm ² The method comprises the steps of carrying out a first treatment on the surface of the SEM images of the anode foil prepared in this example were similar in structure to SEM images of the anode foil prepared in example 1.

Example 8

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.95% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: deionized water of mass M is used as a solvent, polyvinyl alcohol of 4%M and hydroxyethyl cellulose of 4%M are added, and the mixture is stirred for 1h at 75 ℃ and then cooled to 25 ℃. An aluminum foil substrate having a thickness of 30 μm was obtained.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a vacuum sintering furnace, and the sintering temperature is as follows: heating from room temperature to 340 ℃ at a heating rate of 5 ℃/min, and preserving heat for 2 hours; heating to 420 ℃ at a heating rate of 5 ℃/min, and preserving heat for 4 hours; and finally, heating to 650 ℃ at a heating rate of 5 ℃/min, preserving heat for 0.5h, and cooling with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

5. Boiling the sintered aluminum foil in deionized water at 95 ℃ for 15min, and adopting 100g/L boric acid solution to perform formation treatment under the formation voltage of 500V; and cleaning with deionized water, and drying at 100 ℃ to obtain the anode foil for the aluminum electrolytic capacitor.

The static specific capacity of the anode foil for aluminum electrolytic capacitor prepared in this example was 1.07. Mu.F/cm ² The method comprises the steps of carrying out a first treatment on the surface of the SEM images of the anode foil prepared in this example were similar in structure to SEM images of the anode foil prepared in example 1.

Example 9

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.95% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: deionized water of mass M is used as a solvent, polyvinyl alcohol of 6%M and hydroxyethyl cellulose of 2%M are added, and the mixture is stirred for 1h at 75 ℃ and then cooled to 25 ℃. An aluminum foil substrate having a thickness of 30 μm was obtained.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a sintering furnace in nitrogen atmosphere, and the sintering temperature is as follows: heating from room temperature to 340 ℃ at a heating rate of 1 ℃/min, and preserving heat for 2 hours; heating to 420 ℃ at a heating rate of 1 ℃/min, and preserving heat for 4 hours; and finally, heating to 650 ℃ at a heating rate of 1 ℃/min, preserving heat for 2 hours, and cooling along with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

5. Boiling the sintered aluminum foil in deionized water at 100 ℃ for 15min, and adopting a boric acid solution of 100g/L to perform formation treatment under a formation voltage of 520V; and cleaning with deionized water, and drying at 100 ℃ to obtain the anode foil for the aluminum electrolytic capacitor.

The static specific capacity of the anode foil for aluminum electrolytic capacitor prepared in this example was 1.18. Mu.F/cm ² The method comprises the steps of carrying out a first treatment on the surface of the SEM images of the anode foil prepared in this example were similar in structure to SEM images of the anode foil prepared in example 1.

The aqueous binder in examples 4 to 9 may also be any one of a polyvinyl alcohol and polyvinylpyrrolidone combination, a polyvinyl alcohol and hydroxypropyl methylcellulose combination, a polyvinyl alcohol and hydroxyethyl methylcellulose combination, a hydroxyethyl cellulose and polyvinylpyrrolidone combination, a hydroxyethyl cellulose and hydroxypropyl methylcellulose combination, a hydroxyethyl cellulose and hydroxyethyl methylcellulose combination, a polyvinyl pyrrolidone and hydroxypropyl methylcellulose combination, a polyvinyl pyrrolidone and hydroxyethyl methylcellulose combination, a hydroxypropyl methylcellulose and hydroxyethyl methylcellulose combination, and the like.

Example 10

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.99% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: adding 1%M polyvinyl alcohol, 1%M hydroxyethyl cellulose and 2%M polyvinylpyrrolidone into deionized water with mass M as a solvent, stirring at 75 ℃ for 1h, and cooling to 25 ℃. An aluminum foil substrate having a thickness of 60 μm was obtained.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a sintering furnace in argon atmosphere, and the sintering temperature is as follows: heating from room temperature to 380 ℃ at a heating rate of 10 ℃/min, and preserving heat for 1h; heating to 460 ℃ at a heating rate of 10 ℃/min, and preserving heat for 1h; and finally heating to 630 ℃ at a heating rate of 10 ℃/min, preserving heat for 2 hours, and cooling along with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

5. Boiling the sintered aluminum foil in deionized water at 98 ℃ for 10min, and adopting 110g/L boric acid solution to perform formation treatment under 590V formation voltage; and cleaning with deionized water, and drying at 100 ℃ to obtain the anode foil for the aluminum electrolytic capacitor.

The static specific capacity of the anode foil for the aluminum electrolytic capacitor prepared in the present example was 1.06. Mu.F/cm ² The method comprises the steps of carrying out a first treatment on the surface of the SEM images of the anode foil prepared in this example were similar in structure to SEM images of the anode foil prepared in example 1.

Example 11

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.99% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: the deionized water of mass M is used as a solvent, and the polyvinyl alcohol of 1%M, the 2%M hydroxyethyl cellulose and the hydroxypropyl methyl cellulose of 3%M are added, stirred for 1h at 75 ℃ and then cooled to 25 ℃. An aluminum foil substrate having a thickness of 30 μm was obtained.

2. Uniformly paving aluminum powder on the upper surface of an aluminum foil matrix to form an aluminum powder layer with the thickness of 60 mu m; spraying binder solution on the aluminum powder layer, and drying at 100 ℃. The spray adhesive solution adopts a piezoelectric spray head, the distance between the end part of the spray head and the aluminum powder layer is 5cm, and the moving speed of the spray head is 20cm/min.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a sintering furnace in argon atmosphere, and the sintering temperature is as follows: heating from room temperature to 340 ℃ at a heating rate of 1 ℃/min, and preserving heat for 4 hours; heating to 460 ℃ at a heating rate of 5 ℃/min, and preserving heat for 1h; and finally, heating to 620 ℃ at a heating rate of 5 ℃/min, preserving heat for 8 hours, and cooling with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

The static specific capacity of the anode foil for aluminum electrolytic capacitor prepared in this example was 1.17. Mu.F/cm ² The method comprises the steps of carrying out a first treatment on the surface of the SEM images of the anode foil prepared in this example were similar in structure to SEM images of the anode foil prepared in example 1.

Example 12

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.95% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: the deionized water of mass M is used as a solvent, and the polyvinyl alcohol of 1%M, the 4%M hydroxyethyl cellulose and the hydroxyethyl methylcellulose of 3%M are added, stirred for 1h at 75 ℃ and then cooled to 25 ℃. An aluminum foil substrate having a thickness of 30 μm was obtained.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a vacuum sintering furnace, and the sintering temperature is as follows: heating from room temperature to 340 ℃ at a heating rate of 1 ℃/min, and preserving heat for 4 hours; heating to 440 ℃ at a heating rate of 10 ℃/min, and preserving heat for 2 hours; finally heating to 640 ℃ at a heating rate of 10 ℃/min, preserving heat for 2 hours, and cooling along with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

5. Boiling the sintered aluminum foil in deionized water at 98 ℃ for 12min, and adopting 100g/L boric acid solution to perform formation treatment under 520V formation voltage; and cleaning with deionized water, and drying at 100 ℃ to obtain the anode foil for the aluminum electrolytic capacitor.

The static specific capacity of the anode foil for aluminum electrolytic capacitor prepared in this example was found to be 0.86. Mu.F/cm ² The method comprises the steps of carrying out a first treatment on the surface of the SEM images of the anode foil prepared in this example were similar in structure to SEM images of the anode foil prepared in example 1.

Example 13

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.95% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: adding 2%M polyvinyl alcohol, 1%M hydroxyethyl cellulose and 4%M polyvinylpyrrolidone into deionized water with mass M as a solvent, stirring at 75 ℃ for 1h, and cooling to 25 ℃. An aluminum foil substrate having a thickness of 40 μm was obtained.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a sintering furnace in argon atmosphere, and the sintering temperature is as follows: heating from room temperature to 300 ℃ at a heating rate of 1 ℃/min, and preserving heat for 4 hours; heating to 420 ℃ at a heating rate of 5 ℃/min, and preserving heat for 2 hours; and finally heating to 620 ℃ at a heating rate of 10 ℃/min, preserving heat for 10 hours, and cooling along with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

Example 14

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.99% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: the deionized water of mass M is used as a solvent, and the polyvinyl alcohol of 2%M, the 2%M hydroxyethyl cellulose and the hydroxypropyl methyl cellulose of 2%M are added, stirred for 1h at 75 ℃ and then cooled to 25 ℃. An aluminum foil substrate having a thickness of 40 μm was obtained.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a vacuum sintering furnace, and the sintering temperature is as follows: heating from room temperature to 380 ℃ at a heating rate of 5 ℃/min, and preserving heat for 1h; heating to 440 ℃ at a heating rate of 1 ℃/min, and preserving heat for 2 hours; and finally, heating to 630 ℃ at a heating rate of 5 ℃/min, preserving heat for 6 hours, and cooling along with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

The static specific capacity of the anode foil for aluminum electrolytic capacitor prepared in this example was 1.22. Mu.F/cm ² The method comprises the steps of carrying out a first treatment on the surface of the SEM images of the anode foil prepared in this example were similar in structure to SEM images of the anode foil prepared in example 1.

Example 15

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.99% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: the deionized water of mass M is used as a solvent, and the polyvinyl alcohol of 2%M, the 3%M hydroxyethyl cellulose and the hydroxyethyl methylcellulose of 3%M are added, stirred for 1h at 75 ℃ and then cooled to 25 ℃. An aluminum foil substrate having a thickness of 20 μm was obtained.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a sintering furnace in argon atmosphere, and the sintering temperature is as follows: heating from room temperature to 380 ℃ at a heating rate of 5 ℃/min, and preserving heat for 3 hours; heating to 420 ℃ at a heating rate of 1 ℃/min, and preserving heat for 6 hours; and finally, heating to 630 ℃ at a heating rate of 1 ℃/min, preserving heat for 4 hours, and cooling along with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

5. Boiling the sintered aluminum foil in deionized water at 98 ℃ for 10min, and adopting 100g/L boric acid solution to perform formation treatment under 520V formation voltage; and cleaning with deionized water, and drying at 100 ℃ to obtain the anode foil for the aluminum electrolytic capacitor.

Example 16

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.95% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: adding 3%M polyvinyl alcohol, 2%M hydroxyethyl cellulose and 2%M polyvinylpyrrolidone into deionized water with mass M as a solvent, stirring at 75 ℃ for 1h, and cooling to 25 ℃. An aluminum foil substrate having a thickness of 20 μm was obtained.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a sintering furnace in nitrogen atmosphere, and the sintering temperature is as follows: heating from room temperature to 380 ℃ at a heating rate of 5 ℃/min, and preserving heat for 1h; heating to 460 ℃ at a heating rate of 1 ℃/min, and preserving heat for 6 hours; finally heating to 640 ℃ at a heating rate of 10 ℃/min, preserving heat for 2 hours, and cooling along with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

Example 17

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.95% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: the deionized water of mass M is used as a solvent, and the polyvinyl alcohol of 3%M, the 1%M hydroxyethyl cellulose and the hydroxypropyl methyl cellulose of 4%M are added, stirred for 1h at 75 ℃ and then cooled to 25 ℃. An aluminum foil substrate having a thickness of 30 μm was obtained.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a vacuum sintering furnace, and the sintering temperature is as follows: heating from room temperature to 340 ℃ at a heating rate of 10 ℃/min, and preserving heat for 2 hours; heating to 420 ℃ at a heating rate of 1 ℃/min, and preserving heat for 6 hours; and finally, heating to 620 ℃ at a heating rate of 5 ℃/min, preserving heat for 6 hours, and cooling with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

The static specific capacity of the anode foil for aluminum electrolytic capacitor prepared in this example was found to be 0.96. Mu.F/cm ² The method comprises the steps of carrying out a first treatment on the surface of the This practice isSEM images of the anode foil obtained by example preparation were similar in structure to SEM images of the anode foil obtained by example 1 preparation.

Example 18

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.99% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: the deionized water of mass M is used as a solvent, and the polyvinyl alcohol of 3%M, the 4%M hydroxyethyl cellulose and the hydroxyethyl methylcellulose of 1%M are added, stirred for 1h at 75 ℃ and then cooled to 25 ℃. An aluminum foil substrate having a thickness of 60 μm was obtained.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a sintering furnace in argon atmosphere, and the sintering temperature is as follows: heating from room temperature to 340 ℃ at a heating rate of 10 ℃/min, and preserving heat for 3 hours; heating to 460 ℃ at a heating rate of 5 ℃/min, and preserving heat for 2 hours; and finally, heating to 650 ℃ at a heating rate of 1 ℃/min, preserving heat for 6 hours, and cooling along with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

5. Boiling the sintered aluminum foil in deionized water at 98 ℃ for 15min, and adopting 100g/L boric acid solution to perform formation treatment under 520V formation voltage; and cleaning with deionized water, and drying at 100 ℃ to obtain the anode foil for the aluminum electrolytic capacitor.

Example 19

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.99% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: adding 4%M polyvinyl alcohol, 1%M hydroxyethyl cellulose and 1%M polyvinylpyrrolidone into deionized water with mass M as a solvent, stirring at 75 ℃ for 1h, and cooling to 25 ℃. An aluminum foil substrate having a thickness of 30 μm was obtained.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a sintering furnace in nitrogen atmosphere, and the sintering temperature is as follows: heating from room temperature to 340 ℃ at a heating rate of 10 ℃/min, and preserving heat for 2 hours; heating to 440 ℃ at a heating rate of 5 ℃/min, and preserving heat for 2 hours; and finally, heating to 650 ℃ at a heating rate of 5 ℃/min, preserving heat for 2 hours, and cooling along with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

The static specific capacity of the anode foil for aluminum electrolytic capacitor prepared in this example was found to be 0.99. Mu.F/cm ² The method comprises the steps of carrying out a first treatment on the surface of the SEM images of the anode foil prepared in this example were similar in structure to SEM images of the anode foil prepared in example 1.

Example 20

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.95% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: the deionized water of mass M is used as a solvent, and the polyvinyl alcohol of 4%M, the 2%M hydroxyethyl cellulose and the hydroxypropyl methyl cellulose of 2%M are added, stirred for 1h at 75 ℃ and then cooled to 25 ℃. An aluminum foil substrate having a thickness of 50 μm was obtained.

4. and sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a vacuum sintering furnace, and the sintering temperature is as follows: heating from room temperature to 300 ℃ at a heating rate of 10 ℃/min, and preserving heat for 4 hours; heating to 460 ℃ at a heating rate of 10 ℃/min, and preserving heat for 4 hours; and finally heating to 620 ℃ at a heating rate of 10 ℃/min, preserving heat for 8 hours, and cooling along with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

The static specific capacity of the anode foil for aluminum electrolytic capacitor prepared in this example was found to be 0.84. Mu.F/cm ² The method comprises the steps of carrying out a first treatment on the surface of the SEM images of the anode foil prepared in this example were similar in structure to SEM images of the anode foil prepared in example 1.

Example 21

1. Obtaining dried aluminum powder: spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.95% is dried for 2 hours in vacuum at the temperature of 100 ℃. Obtaining a binder solution: the deionized water of mass M is used as a solvent, and the polyvinyl alcohol of 4%M, the 3%M hydroxyethyl cellulose and the hydroxyethyl methylcellulose of 1%M are added, stirred for 1h at 75 ℃ and then cooled to 25 ℃. An aluminum foil substrate having a thickness of 50 μm was obtained.

3. And (3) turning over the aluminum foil substrate for 180 degrees, and repeating the operation of the step (2) to obtain the aluminum foil substrate with the double aluminum powder layers.

4. And sintering the aluminum foil matrix with the double aluminum powder layers. The sintering process is carried out in a sintering furnace in argon atmosphere, and the sintering temperature is as follows: heating from room temperature to 300 ℃ at a heating rate of 5 ℃/min, and preserving heat for 5 hours; heating to 420 ℃ at a heating rate of 5 ℃/min, and preserving heat for 6 hours; finally heating to 640 ℃ at a heating rate of 5 ℃/min, preserving heat for 6 hours, and cooling along with a furnace after the heat preservation is finished to obtain the sintered aluminum foil.

The static specific capacity of the anode foil for aluminum electrolytic capacitor prepared in this example was 1.23. Mu.F/cm ² The method comprises the steps of carrying out a first treatment on the surface of the SEM images of the anode foil prepared in this example were similar in structure to SEM images of the anode foil prepared in example 1.

Example 10-the aqueous binder in example 21 may be any one of a polyvinyl alcohol, a hydroxyethyl cellulose, and a hydroxypropyl methylcellulose combination, a polyvinyl alcohol, a hydroxyethyl cellulose, and a polyvinyl pyrrolidone combination, a polyvinyl alcohol, a hydroxyethyl cellulose, and a hydroxyethyl methylcellulose combination, a polyvinyl alcohol, a polyvinyl pyrrolidone, and a hydroxypropyl methylcellulose combination, a polyvinyl alcohol, a polyvinyl pyrrolidone, and a hydroxyethyl methylcellulose combination, a polyvinyl alcohol, a hydroxypropyl methylcellulose, and a hydroxyethyl methylcellulose combination, a hydroxyethyl cellulose, a polyvinyl pyrrolidone, and a hydroxypropyl methylcellulose combination, a hydroxyethyl cellulose, a polyvinyl pyrrolidone, and a hydroxyethyl methylcellulose combination, a hydroxyethyl cellulose, a hydroxyethyl methylcellulose, a polyvinyl pyrrolidone, a hydroxypropyl methylcellulose, and a hydroxyethyl methylcellulose combination, and the like.

The embodiment of the disclosure also provides an aluminum electrolytic capacitor, which comprises the anode foil prepared by the preparation method provided by any one of the examples.

It should be noted that although the various steps of the method of preparing an aqueous binder-based anode foil in the present disclosure are described in a particular order in the specification, this does not require or imply that the steps must be performed in that particular order or that all of the illustrated steps must be performed in order to achieve the desired results. Additionally or alternatively, certain steps may be omitted, multiple steps combined into one step to perform, and/or one step decomposed into multiple steps to perform, etc.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any adaptations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

Claims

1. A method for preparing an anode foil based on an aqueous binder, comprising the steps of:

obtaining an aluminum foil matrix;

spraying the binder solution on the aluminum powder layer, and drying;

2. The method of preparing an anode foil based on an aqueous binder according to claim 1, wherein in step S1, the aqueous binder is one or more of polyvinyl alcohol, hydroxyethyl cellulose, polyvinylpyrrolidone, hydroxypropyl methylcellulose, and hydroxyethyl methylcellulose.

3. The method for producing an anode foil based on an aqueous binder according to claim 1, wherein in step S1, the mass purity of the aluminum powder is 99.95% or more.

4. The method for producing an anode foil based on an aqueous binder according to claim 1, wherein in step S1, the aluminum particles in the aluminum powder are spherical in shape.

5. The method of producing an aqueous binder-based anode foil according to claim 1, wherein in step S2, the spraying of the binder solution onto the aluminum powder layer is spraying with a shower head; the distance between the end part of the spray head and the aluminum powder layer is 5-15 cm, and the moving speed of the spray head is 20-30 cm/min.

6. The method of preparing an anode foil based on an aqueous binder according to any one of claims 1-5, wherein in step S4, the sintering is performed in a nitrogen, argon or vacuum atmosphere at a sintering temperature of: heating from room temperature to 300-380 ℃ at a heating rate of 1-10 ℃/min, and preserving heat for 1-5 h; heating to 420-460 ℃ at a heating rate of 1-10 ℃/min, and preserving heat for 1-6 h; heating to 620-650 ℃ at a heating rate of 1-10 ℃/min, and preserving heat for 0.5-10 h.

7. The method of preparing an anode foil based on an aqueous binder according to claim 6, wherein in step S5, the water-boiling treatment is performed with deionized water, and the water-boiling treatment is performed at 95 to 100 ℃ for 10 to 15 minutes.

8. The method of producing an aqueous binder-based anode foil according to claim 7, wherein in step S1, the thickness of the aluminum foil substrate is 20 to 60 μm.

9. The method for preparing an anode foil based on an aqueous binder according to claim 1, comprising the steps of:

in step S1, the obtaining dry aluminum powder is: drying spherical aluminum powder with the particle size of 1-5 mu m and the mass purity of 99.95% in vacuum at 100 ℃ for 2h;

the binder solution is obtained by: adding 4%M polyvinyl alcohol, 3%M hydroxyethyl cellulose and 1%M hydroxyethyl methylcellulose into M deionized water serving as a solvent, stirring at 75 ℃ for 1h, and cooling to 25 ℃;

obtaining an aluminum foil substrate with the thickness of 50 mu m;

10. An aluminum electrolytic capacitor comprising the anode foil produced by the method for producing an anode foil based on an aqueous binder according to any one of claims 1 to 9.