Electrode material and method for producing the same

Abstract

This invention provides a method for preparing an electrode material, the method comprising: S1 coating: mixing a solvent and a crosslinking agent, and performing a coating process to obtain a glue solution; S2 molding: dispersing aluminum powder in the glue solution, and pressing to form a molding process to obtain the material to be processed; wherein the molding process is performed twice or more, and the particle size D of the aluminum powder used in adjacent molding processes is... 50 Different; S3 sintering: The material to be processed is sintered to obtain the electrode material. The electrode material obtained by the preparation method provided by this invention has a large specific surface area, and the capacitors made from it have high electrostatic capacitance, thereby achieving small volume and high capacitance under specific voltage resistance conditions.

Description

Technical Field

[0001] This invention relates to the field of electrode materials, and more specifically to an electrode material and its preparation method. Background Technology

[0002] Sintered foil electrolytic capacitors are a new type of high-performance electrolytic capacitor developed in the 21st century. Their advantages lie in improved specific capacitance and production efficiency. However, most existing aluminum electrolytic capacitors are wound, formed by winding electrolytic paper, positive foil, and negative foil together. This method results in a larger size for wound aluminum electrolytic capacitors, and the winding process requires high resistance to bending of the anode foil, making the foil edges prone to micro-cracks. Furthermore, the rapid trend towards thinner, lighter, and smaller electronic devices means that the relatively large size of aluminum electrolytic capacitors, which still plays an irreplaceable role in circuits, has become a limiting factor. Summary of the Invention

[0003] To address the problems existing in the prior art, the present invention provides a method for preparing electrode materials. The electrode materials obtained by the preparation method provided by the present invention have a large specific surface area, and the capacitors made from them have high electrostatic capacitance, thereby achieving small size and high capacity under specific voltage resistance conditions.

[0004] On one hand, the present invention provides a method for preparing an electrode material, the method comprising:

[0005] S1 adhesive application: The solvent and crosslinking agent are mixed and applied to obtain an adhesive solution;

[0006] S2 Plastic Film: Aluminum powder is dispersed in an adhesive solution and pressed into shape to obtain the material to be treated; wherein, the plastic film is processed two or more times, and the particle size D of the aluminum powder used in adjacent plastic film processes is... 50 different;

[0007] S3 Sintering: The material to be processed is sintered to obtain the electrode material.

[0008] The electrode material prepared by the method provided by this invention has a large specific surface area and high bending resistance. The capacitor made from it has high electrostatic capacitance, realizing small volume and high capacitance under specific voltage resistance conditions. Therefore, the method of this invention can effectively solve the problem that the electrode foil, such as the anode foil, has high bending resistance requirements during the winding process when preparing capacitors, and that micro-cracks are easy to appear on the edge of the foil.

[0009] In this invention, at least one of the following technical features may be further included:

[0010] According to embodiments of the present invention, the type of solvent is not particularly limited, and the solvent may be selected from at least one of ethanol, water, toluene, acetone, and ethylene glycol ethyl ether, but is not limited to the above choices.

[0011] According to embodiments of the present invention, the type of crosslinking agent is not particularly limited. The crosslinking agent may be selected from at least one of epoxy resin, vinyl alcohol resin, fluoroethylene resin, epoxy resin, paraffin wax, and ethyl cellulose, but is not limited to the above selections.

[0012] According to an embodiment of the present invention, the mass ratio of solvent to crosslinking agent can be (5-100):1.

[0013] According to an embodiment of the present invention, the mass ratio of solvent to crosslinking agent is preferably (5-50):1.

[0014] According to an embodiment of the present invention, the preferred mass ratio of solvent to crosslinking agent is (5-20):1.

[0015] According to an embodiment of the present invention, the mass ratio of solvent to crosslinking agent is preferably (5-10):1.

[0016] According to an embodiment of the present invention, the mass ratio of solvent to crosslinking agent is preferably (5-7.5):1.

[0017] According to an embodiment of the present invention, the preferred mass ratio of solvent to crosslinking agent is (7.5-10):1.

[0018] Optionally, the mass ratio of solvent to crosslinking agent is any value within the range of (5-100):1. Specifically, the mass ratios of solvent to crosslinking agent are 5:1, 7.5:1, 10:1, 12.5:1, 15:1, 17.5:1, 20:1, 22.5:1, 25:1, 27.5:1, 30:1, 32.5:1, 35:1, 37.5:1, 40:1, 42.5:1, 45:1, 47.5:1, 50:1, 52.5:1, 55:1, etc. 1. 57.5:1, 60:1, 62.5:1, 65:1, 67.5:1, 70:1, 72.5:1, 75:1, 77.5:1, 80:1, 82.5:1, 85:1, 87.5:1, 90:1, 92.5:1, 95:1, 97.5:1, 100:1, or any range formed by any two of the above endpoints, or any value within the range.

[0019] According to an embodiment of the present invention, the aluminum powder used in the S2 plastic film is independently selected from either small-particle aluminum powder or large-particle aluminum powder.

[0020] Unless otherwise stated, the terms "small particle aluminum powder" and "large particle aluminum powder" in this invention refer to two types of aluminum powder with different particle sizes (e.g., average particle size), with the small particle aluminum powder having a smaller particle size than the large particle aluminum powder.

[0021] According to an embodiment of the present invention, the particle size D of aluminum powder used in two adjacent plastic films is... 50 different.

[0022] According to an embodiment of the present invention, small particle aluminum powder D 50 The range is 0.1-3.5 μm.

[0023] According to an embodiment of the present invention, small particle aluminum powder D 50 The preferred size is 0.5-3.0 μm.

[0024] According to an embodiment of the present invention, small particle aluminum powder D 50 The preferred size is 1.0-3.0 μm.

[0025] According to an embodiment of the present invention, small particle aluminum powder D 50 The preferred size is 1.5-3.0 μm.

[0026] According to an embodiment of the present invention, small particle aluminum powder D 50 The preferred size is 1.5-2.5 μm.

[0027] Optionally, small-particle aluminum powder D 50 It can be any value within the range of 0.1-3.5μm. Specifically, for small-particle aluminum powder, D... 50 The value is 0.1μm, 0.5μm, 1.0μm, 1.5μm, 2.0μm, 2.5μm, 3.0μm, 3.5μm, or any range formed by any two of the above endpoints, or any value within the range.

[0028] According to an embodiment of the present invention, large particle aluminum powder D 50 The range is 3.5-20μm.

[0029] According to an embodiment of the present invention, large particle aluminum powder D 50 The preferred size is 3.5-15μm.

[0030] According to an embodiment of the present invention, large particle aluminum powder D 50 The preferred size is 3.5-10 μm.

[0031] According to an embodiment of the present invention, large particle aluminum powder D 50 The preferred size is 3.5-5.5 μm.

[0032] According to an embodiment of the present invention, large particle aluminum powder D 50 The preferred size is 3.5-4.5 μm.

[0033] Optional, large-particle aluminum powder D 50 It can be any value within the range of 3.5-20μm. Large particle aluminum powder D 50 The value is 3.5μm, 4.0μm, 4.5μm, 5.0μm, 5.5μm, 6.0μm, 7.0μm, 8.0μm, 9.0μm, 10.0μm, 11.0μm, 12.0μm, 13.0μm, 14.0μm, 15.0μm, 16.0μm, 17.0μm, 8.0μm, 19.0μm, 20.0μm, or any value within the range formed by any two of the above endpoints.

[0034] When the aluminum powder particle size is less than 0.1 μm, the pore size after sintering is too small, making it difficult for the electrolyte to penetrate; while when the aluminum powder particle size is greater than 20 μm, the specific surface area after sintering is too low, resulting in a reduction in capacity.

[0035] Low particle size exhibits high specific surface area and small pore size. When the aluminum powder particle size is small, the pores in the powder layer are also small. After formation, the pores are further reduced and spheroidized, and a dense and brittle alumina film is formed on the pore surface. When the formation voltage is high, large-area powder adhesion occurs, clogging the pores and making it difficult for the electrolyte to penetrate. High particle size exhibits low specific surface area and large pore size. When the aluminum powder particle size is large, the pores in the powder layer are larger, and the electrolyte can penetrate more easily. After formation, the pores are reduced and spheroidized, but a certain size is still maintained to allow the electrolyte to penetrate. Furthermore, large-particle-size aluminum powder, after sintering, has a larger sintering neck (the overlapping portion between aluminum powder particles), and the bonding between aluminum powder particles in the powder layer is stronger. Therefore, this invention uses a layered stacking method of aluminum powder with different particle sizes to make a sintered body, ensuring that when the formation voltage is high, there will be no large-area powder adhesion, which will block the gaps and make it difficult for the electrolyte to penetrate, and making it easier for the electrolyte to penetrate. The capacitor made by the sintered body made by the method described in this invention has a higher capacitance than the capacitor made by the sintered body obtained by stacking aluminum powder with a single particle size.

[0036] According to an embodiment of the present invention, in the S2 molding process, the lead wire is placed in the mold and molding is performed.

[0037] According to an embodiment of the present invention, the lead wire is preferably aluminum foil.

[0038] According to an embodiment of the present invention, the mold can be selected from any shape, preferably cylindrical, cubic or cuboid.

[0039] According to an embodiment of the present invention, the S2 plastic film includes S2.1 primary plastic film and S2.2 secondary plastic film; optionally, it also includes S2.3 tertiary plastic film.

[0040] According to an embodiment of the present invention, the mold volume used for the secondary plastic film in S2.2 is larger than the mold volume used for the primary plastic film in S2.1, and the mold volume used for the tertiary plastic film in S2.3 is larger than the mold volume used for the secondary plastic film in S2.2.

[0041] According to an embodiment of the present invention, in S3, a pre-sintering treatment is performed before sintering. Optionally, the temperature of the pre-sintering treatment is 300-450°C; optionally, the time of the pre-sintering treatment is 0.1-100h, preferably 0.1-20h, and more preferably 0.1-10h.

[0042] Specifically, the pre-sintering temperature is any value within the range of 300-450℃. The pre-sintering temperature can be 300℃, 350℃, 400℃, 450℃, or any range consisting of any two of the above endpoints, or any value within that range.

[0043] Specifically, the pre-sintering treatment time is any value within the range of 0.1-100h. The pre-sintering treatment time is 0.1h, 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, 12h, 13h, 14h, 15h, 16h, 17h, 18h, 19h, 20h, 30h, 40h, 50h, 60h, 70h, 80h, 90h, 100h, or any value within the range formed by any two of the above endpoints.

[0044] According to an embodiment of the present invention, optionally, in S3, the sintering temperature is 500-650°C.

[0045] According to an embodiment of the present invention, optionally, in S3, the sintering time is 0.1-100h, preferably 1-50h, preferably 1-20h, and more preferably 1-10h.

[0046] Specifically, the sintering temperature is any value within the range of 500-650℃. The sintering temperature can be 500℃, 550℃, 600℃, 640℃, or any range consisting of any two of the above endpoints, or any value within that range.

[0047] Specifically, the sintering time is any value within the range of 0.1-100h. The sintering time can be 0.1h, 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, 12h, 13h, 14h, 15h, 16h, 17h, 18h, 19h, 20h, 30h, 40h, 50h, 60h, 70h, 80h, 90h, 100h, or any value within the range defined by any two of the above endpoints.

[0048] According to an embodiment of the present invention, in the S2 plastic film, the mass ratio of aluminum powder to adhesive liquid is independently (0.1-10):1.

[0049] According to an embodiment of the present invention, in the S2 plastic film, the mass ratio of aluminum powder to adhesive liquid is independently (0.1-8):1.

[0050] According to an embodiment of the present invention, in the S2 plastic film, the mass ratio of aluminum powder to adhesive liquid is independently (0.1-5):1.

[0051] According to an embodiment of the present invention, in the S2 plastic film, the mass ratio of aluminum powder to adhesive liquid is independently (0.1-1):1.

[0052] Optionally, in the S2 plastic film, the mass ratio of aluminum powder to adhesive is any value within the range of (0.1-10):1. Specifically, in the S2 plastic film, the mass ratio of aluminum powder to adhesive is independently 0.1:1, 0.2:1, 0.3:1, 0.4:1, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, or any value within the range formed by any two of the above endpoints.

[0053] According to an embodiment of the present invention, the sintering in S3 is carried out under a vacuum, an inert or a reducing atmosphere; the inert atmosphere is selected from, but not limited to, at least one of helium, neon, argon and nitrogen; the reducing atmosphere is selected from, but not limited to, at least one of hydrogen, alkanes and alkenes.

[0054] According to an embodiment of the present invention, the pressure applied during the pressurization process is independently 2-10 MPa.

[0055] According to an embodiment of the present invention, the pressure applied during the pressurization process is independently 2-5 MPa.

[0056] Optionally, the pressure applied during the compression molding process is any value within the range of 2-10 MPa. The pressure applied during the compression molding process is individually 2 MPa, 2.5 MPa, 3.0 MPa, 3.5 MPa, 4.0 MPa, 4.5 MPa, 5.0 MPa, 5.5 MPa, 6.0 MPa, 6.5 MPa, 7.0 MPa, 7.5 MPa, 8.0 MPa, 8.5 MPa, 9.0 MPa, 9.5 MPa, 10 MPa, or any value within the range formed by any two of the above endpoints.

[0057] In a second aspect, the present invention provides an electrode material prepared by the method described in the first aspect.

[0058] Thirdly, the present invention provides a capacitor, wherein the electrode material used in the capacitor is prepared by the preparation method described in the first aspect;

[0059] Or it may be the electrode material described in the second aspect.

[0060] Compared with the prior art, the present invention has the following technical effects:

[0061] 1. The preparation method described in this invention can effectively solve the problem that during the winding process of capacitor preparation, the anode foil has high requirements for bending resistance and micro-cracks easily appear on the edge of the foil.

[0062] 2. The electrode material prepared by the method provided by this invention has a large specific surface area, resulting in capacitors with high capacitance, thus achieving both small size and high capacitance under specific voltage withstand conditions; and

[0063] 3. The preparation method described in this invention does not require etching, resulting in relatively low pollution. Detailed Implementation

[0064] Embodiments of the present invention are described in detail below. Unless otherwise stated, all technical terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. All patents and publications related to this invention are incorporated herein by reference in their entirety. The terms "comprising" or "including" are open-ended expressions, meaning they include the contents specified in this invention but do not exclude other aspects.

[0065] According to the embodiments provided by the present invention, the present invention particularly provides

[0066] A method for preparing an electrode material, the method comprising:

[0067] S1 adhesive application: The solvent and crosslinking agent are mixed and applied to obtain an adhesive solution;

[0068] The solvent is selected from at least one of ethanol, water, toluene, acetone and ethylene glycol ethyl ether.

[0069] The crosslinking agent is selected from at least one of epoxy resin, vinyl alcohol resin, fluoroethylene resin, epoxy resin, paraffin wax, and ethyl cellulose.

[0070] Optionally, the mass ratio of the solvent to the crosslinking agent is (5-100):1; preferably (5-50):1; preferably (5-20):1; preferably (5-10):1; preferably (5-7.5):1; preferably (7.5-10):1; preferably 5:1, 7.5:1, or 10:1.

[0071] S2 Plastic Film: Aluminum powder is dispersed in an adhesive solution and pressed into shape to obtain the material to be treated; wherein, the plastic film is processed two or more times, and the particle size D of the aluminum powder used in adjacent plastic film processes is... 50 different.

[0072] The mass ratio of aluminum powder to adhesive is (0.1-10):1; preferably (0.1-8):1; preferably (0.1-5):1; preferably (0.1-1):1.

[0073] The aluminum powder used in S2 plastic film is selected independently from either small-particle aluminum powder or large-particle aluminum powder.

[0074] The particle size D of small aluminum powder 50 The micrometer size is 0.1-3.5 μm; preferably 0.5-3.0 μm; preferably 1.0-3.0 μm; preferably 1.5-3.0 μm; preferably 1.5-2.5 μm; preferably 1.5 μm, 2 μm, or 2.5 μm.

[0075] Particle size D of large aluminum powder 50 The micrometer is 3.5-20 μm; preferably 3.5-15 μm; preferably 3.5-10 μm; preferably 3.5-5.5 μm; preferably 3.5-4.5 μm; preferably 3.5 μm, 4.0 μm, or 4.5 μm.

[0076] The pressure applied during the molding process is 2-10 MPa; preferably 2-5 MPa; and more preferably 2 MPa, 2.5 MPa, 3 MPa, 3.5 MPa, 4.0 MPa, 4.5 MPa, or 5 MPa.

[0077] S3 Sintering: Under vacuum, inert or reducing atmosphere, the material to be treated is pre-sintered at 300-450℃ for 0.1-20h, and then sintered at 500-650℃ for 0.1-20h to obtain the electrode material.

[0078] The embodiments of the present invention will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are for illustrative purposes only and should not be considered as limiting the scope of the invention. Where specific conditions are not specified in the examples, they are performed according to the conditions described in the instruction manual, conventional conditions, or conditions recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0079] Example 1

[0080] S1 Glue application: Mix ethylene glycol ethyl ether and ethyl cellulose (mass ratio of ethylene glycol ethyl ether to ethyl cellulose is 7.5:1), and perform glue application to obtain glue solution ①;

[0081] S2 plastic film

[0082] S2.1 One-time film coating: 30g D 504.0μm aluminum powder is added to 170g of adhesive liquid ① and dispersed in the adhesive liquid to obtain the first solid coating liquid ①; the lead wire is placed in the center of the mold 1, the first solid coating liquid ① is injected into the mold 1, and the first pressure treatment is performed (pressure is 2.5MPa). After molding, the mold is demolded to obtain the first plastic film material ①.

[0083] S2.2 Secondary molding: 30g D 50 2.0μm aluminum powder is added to another 170g of adhesive liquid ① to disperse it in the adhesive liquid, thus obtaining a second solid coating liquid ①; the primary plastic film material ① is placed in the center of the mold 2, the second solid coating liquid ① is injected, and a second pressure treatment is performed (pressure is 2.5MPa). After molding, the material is demolded to obtain the material to be treated ①.

[0084] S3 Sintering: The material to be treated ① is placed in a nitrogen atmosphere, pre-sintered at 350℃ for 1 hour, and then heated to 600℃ for 5 hours to obtain electrode material ①.

[0085] Example 2

[0086] S1 Glue application: Mix ethylene glycol ethyl ether and ethyl cellulose (mass ratio of ethylene glycol ethyl ether to ethyl cellulose is 7.5:1), and perform glue application to obtain glue solution ②;

[0087] S2 plastic film

[0088] S2.1 One-time film coating: 30g D 50 2.0μm aluminum powder is added to 170g of adhesive liquid ② and dispersed in the adhesive liquid to obtain the first solid coating liquid ②; the lead wire is placed in the center of the mold 1, the first solid coating liquid ② is injected into the mold 1, and the first pressure treatment is performed (pressure is 2.5MPa). After molding, the mold is demolded to obtain the first plastic film material ②.

[0089] S2.2 Secondary molding: 30g D 50 4.0μm aluminum powder is added to another 170g of adhesive solution ② to disperse it in the adhesive solution, thus obtaining a second solid coating solution ②; the primary plastic film material ② is placed in the center of the mold 2, the second solid coating solution ② is injected, and a second pressure treatment is performed (pressure is 2.5MPa). After molding, the material is demolded to obtain the material to be treated ②.

[0090] S3 Sintering: The material to be treated ② is placed in a nitrogen atmosphere, pre-sintered at 350℃ for 1 hour, and then heated to 600℃ for 5 hours to obtain electrode material ②.

[0091] Example 3

[0092] S1 Glue application: Mix ethylene glycol ethyl ether and ethyl cellulose (mass ratio of ethylene glycol ethyl ether to ethyl cellulose is 7.5:1), and perform glue application to obtain glue solution ③;

[0093] S2 plastic film

[0094] S2.1 One-time film coating: 30g D 50 2.0μm aluminum powder is added to 170g of adhesive liquid ③ and dispersed in the adhesive liquid to obtain the first solid coating liquid ③; the lead wire is placed in the center of the mold 1, the first solid coating liquid ③ is injected into the mold 1, and the first pressure treatment is performed (pressure is 2.5MPa). After molding, the mold is demolded to obtain the first plastic film material ③.

[0095] S2.2 Secondary molding: 30g D 50 4.0μm aluminum powder is added to another 170g of adhesive liquid ③ to disperse it in the adhesive liquid, thus obtaining the second solid coating liquid ③; the primary plastic film material ③ is placed in the center of the mold 2, the second solid coating liquid ③ is injected, and a second pressure treatment is performed (pressure is 2.5MPa). After molding, the mold is demolded to obtain the secondary plastic film material ③.

[0096] S2.3 Three-stage plastic film coating: 30g D 50 2.0μm aluminum powder is added to another 170g of adhesive solution ③ to disperse it in the adhesive solution, thus obtaining the third solid coating solution ③; the secondary plastic film material ③ is placed in the center of the mold 3, the third solid coating solution ③ is injected, and the third pressure treatment is carried out (pressure is 2.5MPa). After molding, the material is demolded to obtain the material to be treated ③.

[0097] S3 Sintering: The material to be treated ③ is placed in a nitrogen atmosphere, pre-sintered at 350℃ for 1 hour, and then heated to 600℃ for 5 hours to obtain electrode material ③.

[0098] Comparative Example 1

[0099] S1 Glue application: Mix ethylene glycol ethyl ether and ethyl cellulose (mass ratio of ethylene glycol ethyl ether to ethyl cellulose is 7.5:1), and perform glue application to obtain glue solution ④.

[0100] S2 plastic film

[0101] S2.1 One-time film coating: 30g D 50 2.0μm aluminum powder is added to 170g of adhesive liquid ④ and dispersed in the adhesive liquid to obtain the first solid coating liquid ④; the lead wire is placed in the center of the mold 1, the first solid coating liquid ④ is injected into the mold 1, and the first pressure treatment is performed (pressure is 2.5MPa). After molding, the mold is demolded to obtain the first plastic film material ④.

[0102] S2.2 Secondary plastic film: 30g D50 2.0μm aluminum powder is added to another 170g of adhesive liquid ④ to disperse it in the adhesive liquid, thus obtaining the second solid coating liquid ④; the primary plastic film material ④ is placed in the center of the mold 2, the second solid coating liquid ④ is injected, and the second pressure treatment is carried out (pressure is 2.5MPa). After molding, the mold is demolded to obtain the material to be treated ④.

[0103] S3 Sintering: The material to be treated ④ is placed in a nitrogen atmosphere, pre-sintered at 350℃ for 1 hour, and then heated to 600℃ for 5 hours to obtain electrode material ④.

[0104] Comparative Example 2

[0105] S1 Glue application: Mix ethylene glycol ethyl ether and ethyl cellulose (mass ratio of ethylene glycol ethyl ether to ethyl cellulose is 7.5:1), and perform glue application to obtain glue solution ⑤.

[0106] S2 plastic film

[0107] S2.1 One-time film coating: 30g D 50 4.0μm aluminum powder is added to 170g of adhesive liquid ⑤ and dispersed in the adhesive liquid to obtain the first solid coating liquid ⑤; the lead wire is placed in the center of the mold 1, the solid coating liquid ⑤ is injected into the mold 1, and the first pressure treatment is performed (pressure is 2.5MPa). After molding, the mold is demolded to obtain the first plastic film material ⑤.

[0108] S2.2 Secondary plastic film: 30g D 50 4.0μm aluminum powder is added to another 170g of adhesive solution ④ to disperse it in the adhesive solution, thus obtaining a second solid coating solution ⑤; the primary plastic film material ⑤ is placed in the center of the mold 2, the second solid coating solution ⑤ is injected, and a second pressure treatment is performed (pressure is 2.5MPa). After molding, the material is demolded to obtain the material to be treated ⑤.

[0109] S3 Sintering: The material to be treated ⑤ is placed in a nitrogen atmosphere, pre-sintered at 350℃ for 1 hour, and then heated to 600℃ for 5 hours to obtain electrode material ⑤.

[0110] Comparative Example 3

[0111] First, a 50 μm layer of the first solid coating liquid ④ prepared in Comparative Example 1 was coated on one side of the aluminum foil, followed by a 50 μm layer of the first solid coating liquid ⑤ prepared in Comparative Example 2. After drying and shaping, the first solid coating liquid ④ prepared in Comparative Example 1 was coated on the reverse side, followed by a 50 μm layer of the first solid coating liquid ⑤ prepared in Comparative Example 2. After drying and shaping, the material to be treated ⑥ was obtained. The material to be treated ⑥ was placed in a nitrogen atmosphere and pre-sintered at 350℃ for 1 h, and then sintered at 600℃ for 5 h to obtain the electrode material ⑥.

[0112] Because the foil is thick and easily broken, it is difficult to achieve subsequent formation and winding, making it impossible to measure the electrostatic capacitance of the foil.

[0113] Performance testing:

[0114] The electrostatic capacitances of the prepared electrode materials ①-⑤ were measured respectively.

[0115] Test method: Electrode materials ①-⑤ were subjected to 510V formation treatment in boric acid aqueous solution (50g / L), and then measured by ammonium borate aqueous solution (3g / L).

[0116] Table 1

[0117] Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 <![CDATA[Effective volume (cm 3 )]]> 6.28 6.25 6.26 6.28 6.25 <![CDATA[Capacitance (μF / cm 3 )]]> 87.25 86.89 89.41 85.33 85.36

[0118] As shown in Table 1, the electrode material prepared by the method of the present invention has a higher electrostatic capacity compared with Comparative Example 1 and Comparative Example 2.

[0119] As can be seen from Comparative Example 3, the preparation method described in this invention can effectively solve the problem that the anode foil has high requirements for bending resistance during the winding process in capacitor preparation, and micro-cracks easily appear on the edge of the foil.

[0120] In the description of this specification, the references to terms such as "some embodiments," "other embodiments," "examples," and "examples" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0121] Although embodiments and examples of the present invention have been shown and described above, it is understood that the above embodiments and examples are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments and examples within the scope of the present invention.

Claims

1. A method for preparing an electrode material, characterized in that, The preparation method includes: S1 adhesive application: The solvent and crosslinking agent are mixed and applied to obtain an adhesive solution; S2 plastic film: Aluminum powder is dispersed in an adhesive solution and then pressed to form the material to be treated; S3 Sintering: The material to be processed is sintered to obtain the electrode material; In S2 plastic film, the lead wire is placed in the mold, plastic film is formed, and demolded after pressure molding. S2 plastic film includes S2.1 primary plastic film and S2.2 secondary plastic film; wherein, the mold volume used for S2.2 secondary plastic film is larger than the mold volume used for S2.1 primary plastic film. Alternatively, S2 plastic film includes S2.1 primary plastic film, S2.2 secondary plastic film, and S2.3 tertiary plastic film, wherein the mold volume used for S2.2 secondary plastic film is larger than the mold volume used for S2.1 primary plastic film, and the mold volume used for S2.3 tertiary plastic film is larger than the mold volume used for S2.2 secondary plastic film. The aluminum powder used in S2.1 primary plastic film, S2.2 secondary plastic film, and S2.3 tertiary plastic film are each independently selected from either small-particle aluminum powder or large-particle aluminum powder. The particle size D of aluminum powder used in two adjacent plastic films 50 different; The particle size D of small aluminum powder 50 The particle size D of large aluminum powder is 1.5-2.5 μm. 50 The thickness is 3.5-4.5 μm; In the S2 plastic film, the pressure applied during molding is 2-10 MPa for each individual.

2. The method for preparing the electrode material according to claim 1, characterized in that, The solvent is selected from at least one of ethanol, water, toluene, acetone, and ethylene glycol ethyl ether; The crosslinking agent is selected from at least one of epoxy resin, vinyl alcohol resin, fluoroethylene resin, epoxy resin, paraffin wax, and ethyl cellulose.

3. The method for preparing the electrode material according to claim 1, characterized in that, The mass ratio of the solvent to the crosslinking agent is (5-100):

1.

4. The method for preparing the electrode material according to claim 1, characterized in that, The mass ratio of the solvent to the crosslinking agent is (5-50):

1.

5. The method for preparing the electrode material according to claim 1, characterized in that, The mass ratio of the solvent to the crosslinking agent is (5-20):

1.

6. The method for preparing the electrode material according to claim 1, characterized in that, The mass ratio of the solvent to the crosslinking agent is (5-10):

1.

7. The method for preparing the electrode material according to claim 1, characterized in that, The mass ratio of the solvent to the crosslinking agent is (5-7.5):

1.

8. The method for preparing the electrode material according to claim 1, characterized in that, The mass ratio of the solvent to the crosslinking agent is (7.5-10):

1.

9. The method for preparing the electrode material according to claim 1, characterized in that, The mass ratio of the solvent to the crosslinking agent is 5:1, 7.5:1, or 10:

1.

10. The method for preparing the electrode material according to claim 1, characterized in that, The particle size D of small aluminum powder 50 are 1.5 μm, 2 μm, and 2.5 μm.

11. The method for preparing the electrode material according to claim 1, characterized in that, Particle size D of large aluminum powder 50 are 3.5 μm, 4.0 μm, and 4.5 μm.

12. The method for preparing the electrode material according to claim 1, characterized in that, In S3, the sintering temperature is 500-650℃.

13. The method for preparing the electrode material according to claim 1, characterized in that, In S3, the sintering time is 1-20 h.

14. The method for preparing the electrode material according to claim 1, characterized in that, In S3, the sintering time is 1-10 h.

15. The method for preparing the electrode material according to claim 1, characterized in that, In S3, a pre-sintering treatment is performed before sintering, wherein the temperature of the pre-sintering treatment is 300-450℃.

16. The method for preparing the electrode material according to claim 15, characterized in that, The pre-sintering treatment time is 0.1-20 h.

17. The method for preparing the electrode material according to claim 15, characterized in that, The pre-sintering treatment time is 0.1-10 h.

18. The method for preparing the electrode material according to claim 1, characterized in that, In S2 plastic film, the mass ratio of aluminum powder to adhesive liquid is (0.1-10):

1.

19. The method for preparing the electrode material according to claim 1, characterized in that, In S2 plastic film, the mass ratio of aluminum powder to adhesive liquid is (0.1-8):

1.

20. The method for preparing the electrode material according to claim 1, characterized in that, In S2 plastic film, the mass ratio of aluminum powder to adhesive liquid is (0.1-5):

1.

21. The method for preparing the electrode material according to claim 1, characterized in that, In S2 plastic film, the mass ratio of aluminum powder to adhesive liquid is (0.1-1):

1.

22. The method for preparing the electrode material according to claim 1, characterized in that, In the S2 plastic film, the pressure applied during molding is 2-5 MPa for each individual.

23. The method for preparing the electrode material according to claim 1, characterized in that, In the S2 plastic film, the pressure for each pressure molding is 2 MPa, 2.5 MPa, 3 MPa, 3.5 MPa, 4.0 MPa, 4.5 MPa, and 5 MPa.

24. The method for preparing the electrode material according to claim 1, characterized in that, S3 sintering is carried out under vacuum, inert, or reducing atmosphere.

25. The method for preparing the electrode material according to claim 24, characterized in that, The inert atmosphere is selected from at least one of helium, neon, argon and nitrogen.

26. The method for preparing the electrode material according to claim 24, characterized in that, The reducing atmosphere is selected from at least one of hydrogen, alkanes, and alkenes.

27. An electrode material, characterized in that, Prepared by the method described in any one of claims 1-26.

28. A capacitor, characterized in that, The electrode material used in the capacitor is prepared by the preparation method according to any one of claims 1-26; Or it may be the electrode material described in claim 27.