Aluminum electrolytic capacitor core package, aluminum electrolytic capacitor and preparation method of aluminum electrolytic capacitor core package

Abstract

The invention relates to the technical field of capacitor manufacturing, in particular to an aluminum electrolytic capacitor core package, an aluminum electrolytic capacitor and a preparation method of the aluminum electrolytic capacitor core package. The aluminum electrolytic capacitor core cladding comprises an anode foil, a cathode foil and electrolytic paper, and the electrolytic paper is located between the anode foil and the cathode foil; the anode foil comprises a laminated foil and an anode tab, the anode tab is connected with one edge of the laminated foil, and the laminated foil is provided with a coating formed by compounding three-dimensional porous spherical aluminum powder particles and porous alumina fibers; the cathode foil comprises a main body foil piece and a cathode tab, and the cathode tab is connected with one edge of the main body foil piece; the anode foil, the electrolytic paper and the cathode foil are wound to form the aluminum electrolytic capacitor core bag, and the anode tab and the cathode tab are respectively positioned at two ends of the aluminum electrolytic capacitor core bag. The aluminum electrolytic capacitor prepared by the aluminum electrolytic capacitor core cladding has the characteristics of shrinkage, high capacity, low internal resistance, large ripple current resistance and good consistency.

Description

Technical Field

[0001] The present invention relates to the technical field of capacitor manufacturing, and in particular to an aluminum electrolytic capacitor core package, an aluminum electrolytic capacitor and a preparation method thereof. Background Art

[0002] At present, the cylindrical aluminum electrolytic capacitors on the market usually use cold riveting lead bars to connect the positive and negative electrode terminals on the capacitor cover. Since the number of lead bars generally does not exceed 4 pairs, the internal resistance of the aluminum electrolytic capacitor is relatively high. During the instantaneous high current charging and discharging process, the lead bars may melt at high temperature, which does not meet the requirements of withstanding large ripple current.

[0003] In order to improve the specific capacitance of aluminum electrolytic capacitors, the traditional etching foil preparation process only increases the specific capacitance of the anode foil by expanding the anode foil confrontation area and increasing the expansion multiple without changing the dielectric constant of the oxide film on the surface of the anode foil, which limits the improvement range of the specific capacitance of the aluminum electrolytic capacitor. The laminated foil process based on the preparation of new sintered metal powder breaks through the limitation of increasing the specific capacitance of aluminum electrolytic capacitors by the traditional expansion method. The high-purity spherical aluminum powder coated on the surface of the high-purity core layer aluminum foil is fully combined with the core layer aluminum foil through a high-temperature sintering process, and finally a powder layer with a three-dimensional porous structure is obtained on the surface of the core layer aluminum foil. The specific capacitance of the laminated foil prepared by this high-temperature sintering process is determined by the particle size of the high-purity spherical aluminum powder and the thickness of the coating, which significantly improves the capacity of the aluminum electrolytic capacitor. However, when the coating thickness of the high-purity spherical aluminum powder reaches more than 200 μm, during the process of winding the anode foil into a core package, the high-purity spherical aluminum powder cracks and de-powders due to the excessive bending curvature of the anode foil at the beginning of winding, which ultimately leads to poor consistency of the aluminum electrolytic capacitor product. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art to at least a certain extent. To this end, the present invention provides an aluminum electrolytic capacitor core pack, an aluminum electrolytic capacitor and a preparation method thereof. The aluminum electrolytic capacitor prepared from the aluminum electrolytic capacitor core pack has the characteristics of being compact, having high capacity, having low internal resistance, being able to withstand large ripple current and having good consistency.

[0005] To this end, the first aspect of the present invention provides an aluminum electrolytic capacitor core pack, the aluminum electrolytic capacitor core pack includes an anode foil, a cathode foil and an electrolytic paper, the electrolytic paper is located between the anode foil and the cathode foil; wherein the anode foil includes a laminated foil and an anode tab, the anode tab is connected to one edge of the laminated foil, the laminated foil has a coating, and the coating is formed by a composite of three-dimensional porous spherical aluminum powder particles and porous alumina fibers; the cathode foil includes a main foil sheet and a cathode tab, the cathode tab is connected to one edge of the main foil sheet; the anode foil, the electrolytic paper and the cathode foil are wound to form the aluminum electrolytic capacitor core pack, and the anode tab and the cathode tab are respectively located at both ends of the aluminum electrolytic capacitor core pack.

[0006] In order to solve the deficiencies in the prior art, the present invention uses a laminated foil with a coating as the anode foil, wherein the coating contains porous alumina fibers, which act as a bridge inside the aluminum powder coating, just like "rebars in building materials", and the three-dimensional porous spherical aluminum powder is like "cement in building materials". The three-dimensional porous spherical aluminum powder particles and porous alumina fibers are composited to form a "reinforced concrete structure", so that the laminated foil with a thickness of more than 200 μm does not fall off during the winding process of the core package, solving the problem of powdering caused by the excessive winding curvature of the traditional laminated foil coating composed only of aluminum powder, and at the same time, it can also increase the capacity of the aluminum electrolytic capacitor. In addition, the aluminum electrolytic capacitor core package has a full-pole ear structure with opposite lead-out, which can also reduce the internal resistance of the prepared aluminum electrolytic capacitor and improve the product's ability to withstand large ripple currents.

[0007] According to an embodiment of the present invention, the widths of the anode foil and the cathode foil are the same.

[0008] According to an embodiment of the present invention, the build-up foil and the main body foil have the same width.

[0009] According to an embodiment of the present invention, the widths of the anode tab and the cathode tab are the same.

[0010] According to an embodiment of the present invention, the thickness of the laminate foil is 201-300 μm and the width is 35-110 mm; the thickness of the main foil is 10-30 μm and the width is 35-110 mm.

[0011] According to an embodiment of the present invention, the thickness of the anode tab is 20-60 μm and the width is 6-15 mm; the thickness of the cathode tab is 10-30 μm and the width is 6-15 mm.

[0012] According to an embodiment of the present invention, the base material of the laminated foil includes plain foil.

[0013] According to an embodiment of the present invention, the material of the anode tab and / or the cathode tab includes plain foil or etched foil.

[0014] According to an embodiment of the present invention, the material of the main foil includes plain foil or corroded foil.

[0015] The second aspect of the present invention provides an aluminum electrolytic capacitor, which includes the aluminum electrolytic capacitor core package described in the first aspect. Thus, the aluminum electrolytic capacitor has the characteristics of high capacity, low internal resistance, high ripple current resistance and good consistency.

[0016] According to an embodiment of the present invention, the aluminum electrolytic capacitor further includes a metal shell, a positive current collector, a negative current collector, a positive terminal cover, a negative terminal cover, a positive electrode column, and a negative electrode column; wherein the cathode tab, the negative current collector, the negative terminal cover, and the negative electrode column are connected in sequence; the anode tab, the positive current collector, the positive terminal cover, and the positive electrode column are connected in sequence; and the aluminum electrolytic capacitor core pack is located in the metal shell.

[0017] According to an embodiment of the present invention, the diameter of the aluminum electrolytic capacitor is 22-60 mm and the height is 45-138 mm.

[0018] The third aspect of the present invention provides a method for preparing the aluminum electrolytic capacitor described in the second aspect, comprising: winding an anode foil, a cathode foil and an electrolytic paper to form an aluminum electrolytic capacitor core package, wherein the anode tab and the cathode tab are respectively located at two ends of the aluminum electrolytic capacitor core package.

[0019] According to an embodiment of the present invention, the preparation method also includes: shaping the tabs of the aluminum electrolytic capacitor core package to obtain a shaped core package; placing the shaped core package in a metal shell, connecting the cathode tab, negative electrode collector, negative terminal cover, and negative electrode column of the shaped core package in sequence, and connecting the anode tab, positive electrode collector, positive terminal cover, and positive electrode column of the shaped core package in sequence.

[0020] According to an embodiment of the present invention, the preparation method further includes: connecting the cathode electrode tab to the negative electrode current collector, and connecting the anode electrode tab to the positive electrode current collector; the negative terminal cover is integrally formed with the negative electrode column and connected to the negative electrode current collector, and the negative terminal cover seals one port of the metal shell through an insulating gasket; the positive terminal cover is integrally formed with the positive electrode column and connected to the positive electrode current collector and another port of the metal shell in sequence.

[0021] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 The schematic diagram of the structure of the aluminum electrolytic capacitor core pack provided by the present invention is shown; Figure 2 The schematic diagram of the structure of the aluminum electrolytic capacitor provided by the present invention is shown.

[0023] Figure numerals: anode foil 1, cathode foil 2, electrolytic paper 3, tape 4, anode tab 5, cathode tab 6, laminated foil 7, main foil 8, aluminum electrolytic capacitor core package 9, metal shell 10, positive electrode collector 11, negative electrode collector 12, positive terminal cover 13, negative terminal cover 14, positive electrode column 15, negative electrode column 16, liquid injection port 17. DETAILED DESCRIPTION

[0024] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be understood as limiting the present invention.

[0025] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. Further, in the description of the present invention, unless otherwise specified, the meaning of "plurality" is two or more.

[0026] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0027] In order to make the present invention more easily understood, certain technical and scientific terms are specifically defined below. Unless otherwise clearly defined elsewhere in this document, all other technical and scientific terms used herein have the meanings commonly understood by those skilled in the art to which the present invention belongs.

[0028] In this document, the terms “include” or “comprising” are open expressions, that is, including the contents specified in the present invention but not excluding other contents.

[0029] In this document, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0030] According to an embodiment of the present invention, the first aspect of the present invention provides an aluminum electrolytic capacitor core pack, the specific structure of which is shown in FIG. Figure 1 The aluminum electrolytic capacitor core pack includes an anode foil 1, a cathode foil 2 and an electrolytic paper 3, wherein the electrolytic paper 3 is located between the anode foil 1 and the cathode foil 2; wherein the anode foil 1 includes a laminated foil 7 and an anode tab 5, wherein the anode tab 5 is connected to one edge of the laminated foil 7, and the laminated foil 7 has a coating, wherein the coating is composited by three-dimensional porous spherical aluminum powder particles and porous alumina fibers; the cathode foil 2 includes a main foil sheet 8 and a cathode tab 6, wherein the cathode tab 6 is connected to one edge of the main foil sheet 8; the anode foil 1, the electrolytic paper 3 and the cathode foil 2 are wound to form the aluminum electrolytic capacitor core pack, wherein the anode tab 5 and the cathode tab 6 are respectively located at two ends of the aluminum electrolytic capacitor core pack.

[0031] The present invention uses a laminated foil 7 with a "reinforced concrete structure" to prepare an aluminum electrolytic capacitor core package, wherein the laminated foil 7 coating contains porous alumina fibers, which act like "reinforcements in building materials" and play a bridging role inside the aluminum powder coating. The three-dimensional porous spherical aluminum powder is like "cement in building materials". The three-dimensional porous spherical aluminum powder particles and porous alumina fibers are composited to form a "reinforced concrete structure", so that the laminated foil 7 with a thickness of more than 200 μm does not fall off during winding into a core package, solving the problem of powdering caused by excessive winding curvature of the traditional laminated foil coating composed only of high-purity aluminum powder. Using it to prepare aluminum electrolytic capacitors can increase the capacity and electrical performance consistency of aluminum electrolytic capacitors and reduce the internal resistance of aluminum electrolytic capacitors.

[0032] According to a specific embodiment of the present invention, the ratio of the three-dimensional porous spherical aluminum powder particles and the porous aluminum oxide fibers in the coating is not particularly limited, and those skilled in the art can select the ratio according to actual conditions.

[0033] According to a specific embodiment of the present invention, the method for preparing the coating is not particularly limited.

[0034] According to a specific embodiment of the present invention, the widths of the anode foil 1 and the cathode foil 2 are the same. Since the anode foil 1 includes a laminated foil 7 and an anode tab 5, and the cathode foil 2 includes a main foil sheet 8 and a cathode tab 6, it can be understood here that the sum of the widths of the laminated foil 7 and the anode tab 5 is the same as the sum of the widths of the main foil sheet 8 and the cathode tab 6. The "width" herein should be understood as its dimension in the axial direction of the core package.

[0035] According to a specific embodiment of the present invention, the widths of the build-up foil 7 and the main foil 8 are the same.

[0036] According to a specific embodiment of the present invention, the thickness and width of the laminated foil 7 are not particularly limited, and those skilled in the art can select them according to the situation. As some specific examples, the thickness of the laminated foil 7 is 201-300 μm, and the width is 35-110 mm. Specifically, the thickness of the laminated foil 7 is 201 μm, 210 μm, 220 μm, 230 μm, 240 μm, 250 μm, 260 μm, 270 μm, 280 μm, 290 μm, 300 μm or any value within the above range. The width of the laminated foil 7 is 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm, 95 mm, 100 mm, 105 mm, 110 mm or any value within the above range.

[0037] According to a specific embodiment of the present invention, the base material of the laminated foil 7 is not particularly limited, and can be selected by a person skilled in the art according to the situation. As some specific examples, the base material of the laminated foil 7 includes plain foil, that is, aluminum foil that has not been processed in other ways. The material of the anode tab 5 connected to the laminated foil 7 includes plain foil or corroded foil, which is conducive to reducing the resistance of the connection between the tab and the current collector. The corroded foil should be understood as a metal aluminum foil obtained by chemical corrosion, electrochemical corrosion or mechanical treatment.

[0038] According to an embodiment of the present invention, the widths of the anode tab 5 and the cathode tab 6 are the same.

[0039] According to a specific embodiment of the present invention, the thickness and width of the anode pole ear 5 are not particularly limited, and those skilled in the art can select them according to the situation. As some specific examples, the thickness of the anode pole ear 5 is 20-60 μm and the width is 6-15 mm. Specifically, the thickness of the anode pole ear 5 is 20 μm, 30 μm, 40 μm, 50 μm, 60 μm or any value within the above range. The width of the anode pole ear 5 is 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm or any value within the above range.

[0040] According to a specific embodiment of the present invention, the thickness of the main body foil 8 is not particularly limited, and those skilled in the art can select it according to the situation. As some specific examples, the thickness of the main body foil 8 is 10-30 μm, and the width is 35-110 mm. Specifically, the thickness of the main body foil 8 is 10 μm, 15 μm, 20 μm, 25 μm, 30 μm or any value within the above range. The width of the main body foil 8 is 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm, 95 mm, 100 mm, 105 mm, 110 mm or any value within the above range.

[0041] According to a specific embodiment of the present invention, the material of the main foil 8 is not particularly limited, and those skilled in the art can select it according to the situation. As some specific examples, the material of the main foil 8 includes plain foil or corroded foil. The material of the cathode tab 6 connected to the main foil 8 includes plain foil or corroded foil, which is conducive to reducing the resistance of the connection between the tab and the current collector.

[0042] According to a specific embodiment of the present invention, the thickness of the cathode ear 6 is not particularly limited, and those skilled in the art can select it according to the situation. As some specific examples, the thickness of the cathode ear 6 is 10-30 μm and the width is 6-15 mm. Specifically, the thickness of the cathode ear 6 is 10 μm, 15 μm, 20 μm, 25 μm, 30 μm or any value within the above range. The width of the cathode ear 6 is 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm or any value within the above range.

[0043] According to a specific embodiment of the present invention, the aluminum electrolytic capacitor core package further includes a tape 4, wherein the tape 4 is located in the middle of the aluminum electrolytic capacitor core package and is wound around the aluminum electrolytic capacitor core package for 1-2.5 turns to prevent the wound aluminum electrolytic capacitor core package from unravelling.

[0044] According to a specific embodiment of the present invention, the thickness of the electrolytic paper is 20-35 μm and the width is 30-120 mm. Specifically, the thickness of the electrolytic paper is 20 μm, 25 μm, 30 μm, 35 μm or any value within the above range. The width of the electrolytic paper is 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm, 95 mm, 100 mm, 105 mm, 110 mm, 115 mm, 120 mm or any value within the above range.

[0045] According to an embodiment of the present invention, the second aspect of the present invention provides an aluminum electrolytic capacitor, which includes the aluminum electrolytic capacitor core package described in the first aspect. Thus, the aluminum electrolytic capacitor has the characteristics of high capacity, low internal resistance, high ripple current resistance and good consistency.

[0046] According to a specific embodiment of the present invention, the aluminum electrolytic capacitor may have Figure 2 The structure shown includes an aluminum electrolytic capacitor core pack 9, a metal shell 10, a positive current collector 11, a negative current collector 12, a positive terminal cover 13, a negative terminal cover 14, a positive column 15, and a negative column 16. The aluminum electrolytic capacitor core pack 9 is located in the metal shell 10, the cathode tab 6 is connected to the negative current collector 12, the negative terminal cover 14, and the negative column 16 in sequence, and the anode tab 5, the positive current collector 11, the positive terminal cover 13, and the positive column 15 are connected in sequence. The positive column 15 has a liquid injection port 17, which is located at the center of the positive column 15 and is used to inject electrolyte into the aluminum electrolytic capacitor core pack.

[0047] According to a specific embodiment of the present invention, the size of the aluminum electrolytic capacitor is not particularly limited, and those skilled in the art can select it according to the situation. As some specific examples, the diameter of the aluminum electrolytic capacitor is 22-60 mm and the height is 45-138 mm. Specifically, the diameter of the aluminum electrolytic capacitor is 22 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm or any value within the above range. The height of the aluminum electrolytic capacitor is 45 mm, 50 mm, 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm, 95 mm, 100 mm, 105 mm, 110 mm, 115 mm, 120 mm, 125 mm, 130 mm, 135 mm, 138 mm or any value within the above range.

[0048] According to an embodiment of the present invention, the third aspect of the present invention provides a method for preparing the aluminum electrolytic capacitor described in the second aspect, comprising: winding an anode foil 1, a cathode foil 2 and an electrolytic paper 3 to form an aluminum electrolytic capacitor core package 9, wherein the anode tab 5 and the cathode tab 6 are respectively located at both ends of the aluminum electrolytic capacitor core package 9.

[0049] According to a specific embodiment of the present invention, the preparation method further includes: shaping the tabs of the aluminum electrolytic capacitor core package 9 to obtain a shaped core package; placing the shaped core package in a metal shell 10, connecting the cathode tab 6, the negative electrode current collector 12, the negative terminal cover 14, and the negative electrode column 16 of the shaped core package in sequence, and connecting the anode tab 5, the positive electrode current collector 11, the positive terminal cover 13, and the positive electrode column 15 of the shaped core package in sequence.

[0050] Specifically, the cathode tab 6, the negative current collector 12, and the negative terminal cap 14 can be connected by laser welding, and the connection of the anode tab 5, the positive current collector 11, and the positive terminal cap 13 is the same. Among them, the negative pole 16 is located at the center of the negative terminal cap 14, and the negative terminal cap 14 can be pre-formed as a whole with the negative pole 16, and connected to the negative current collector 12 in sequence by laser welding, and the positive terminal cap 13 is the same. Among them, the negative terminal cap 14 can seal one port of the metal shell 10 through an insulating gasket to ensure that the fully welded aluminum electrolytic capacitor does not short-circuit.

[0051] The scheme of the present invention will be explained below in conjunction with the embodiments. It will be appreciated by those skilled in the art that the following embodiments are only used to illustrate the present invention and should not be considered as limiting the scope of the present invention. Where specific techniques or conditions are not indicated in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used are not indicated by the manufacturer and are all conventional products that can be obtained commercially.

[0052] Example 1 This embodiment provides a method for preparing an aluminum electrolytic capacitor, and the specific steps are as follows: (1) Use a winding machine to wind the anode foil (the laminated foil with a "reinforced concrete structure" at the bottom is 35 mm wide and 220 μm thick; the upper tab is 6 mm wide and 30 μm thick), the main foil and the cathode tab are both 20 μm thick. The cathode foil (main foil width is 35 mm, tab width is 6 mm) and the electrolytic paper (thickness is 30 μm, width is 41 mm) are wound together into a 22×45 mm (diameter is 22 mm, height is 45 mm) fully welded structure core package; (2) shaping the anode tabs and cathode tabs extending oppositely from both ends of the 22×45 mm Φ fully welded core package obtained in step (1) using a tab shaping machine and then flattening them to obtain a shaped core package; (3) using a laser welding machine to sequentially weld the cathode tab, negative electrode current collector, and negative terminal cover of the shaped core package obtained in step (2) together, with the negative electrode column located at the center of the negative terminal cover and the negative electrode column and the negative terminal cover being integrally formed, to obtain a pre-treated core package; (4) using an automatic shell-introducing machine to pack the pretreated core package obtained in step (3) into an aluminum shell, using a sealing machine to roll-slot-seal and secondary-mold-seal the negative terminal cover with the aluminum shell through an insulating gasket, and then using a laser welding machine to weld the anode tab and the positive electrode current collector together to obtain a 22×45 mm fully welded structure liquid aluminum electrolytic capacitor semi-finished product; (5) The cylindrical liquid aluminum electrolytic capacitor semi-finished product obtained in step (4) and the positive terminal cover are welded together using a laser welding machine. The positive electrode column is located at the center of the positive terminal cover and the positive electrode column and the positive terminal cover are integrally formed. After drying, liquid injection and liquid injection port sealing steps, a Ф22×45 mm fully welded structure liquid aluminum electrolytic capacitor is obtained.

[0053] Example 2 This embodiment provides a method for preparing an aluminum electrolytic capacitor, and the specific steps are as follows: (1) Use a winding machine to wind the anode foil (the laminated foil with a "reinforced concrete structure" at the bottom is 46 mm wide and 220 μm thick; the upper tab is 9 mm wide and 30 μm thick), the main foil and the cathode tab are both 20 μm thick. The cathode foil (main foil width is 46 mm, tab width is 9 mm) and the electrolytic paper (thickness is 30 μm, width is 52 mm) are wound together into a 35×63 mm Φ fully welded structure core package; (2) shaping the anode tabs and cathode tabs extending oppositely from both ends of the Φ35×63 mm fully welded core package obtained in step (1) using a tab shaping machine and then flattening them to obtain a shaped core package; (3) using a laser welding machine to sequentially weld the cathode tab, negative electrode current collector, and negative terminal cover of the shaped core package obtained in step (2) together, with the negative electrode column located at the center of the negative terminal cover and the negative electrode column and the negative terminal cover being integrally formed, to obtain a pre-treated core package; (4) using an automatic shell-introducing machine to pack the pretreated core package obtained in step (3) into an aluminum shell, using a sealing machine to perform roll groove sealing and secondary mold sealing on the negative terminal cover and the aluminum shell through an insulating gasket, and then using a laser welding machine to weld the anode tab and the positive electrode current collector together to obtain a Φ35×63 mm fully welded structure liquid aluminum electrolytic capacitor semi-finished product; (5) The cylindrical liquid aluminum electrolytic capacitor semi-finished product obtained in step (4) and the positive terminal cover are welded together using a laser welding machine. The positive electrode column is located at the center of the positive terminal cover and the positive electrode column and the positive terminal cover are integrally formed. After drying, liquid injection and liquid injection port sealing steps, a Ф35×63 mm fully welded structure liquid aluminum electrolytic capacitor is obtained.

[0054] Example 3 This embodiment provides a method for preparing an aluminum electrolytic capacitor, and the specific steps are as follows: (1) Use a winding machine to wind the anode foil (the laminated foil with a "reinforced concrete structure" at the bottom is 86 mm wide and 240 μm thick; the upper tab is 9 mm wide and 30 μm thick), the main foil and the cathode tab thickness of 20 μm (the main foil width is 86 mm, the tab width is 9 mm) and the electrolytic paper (thickness is 30 μm, width is 92 mm) together into a Ф35×103 mm fully welded structure core package; (2) shaping the anode tabs and cathode tabs extending oppositely from both ends of the Φ35×103 mm fully welded core package obtained in step (1) using a tab shaping machine and then flattening them to obtain a shaped core package; (3) using a laser welding machine to sequentially weld the cathode tab, negative electrode current collector, and negative terminal cover of the shaped core package obtained in step (2) together, with the negative electrode column located at the center of the negative terminal cover and the negative electrode column and the negative terminal cover being integrally formed, to obtain a pre-treated core package; (4) using an automatic shell-introducing machine to pack the pretreated core package obtained in step (3) into an aluminum shell, using a sealing machine to perform roller groove sealing and secondary mold sealing on the negative terminal cover and the aluminum shell through an insulating gasket, and then using a laser welding machine to weld the anode tab and the positive electrode current collector together to obtain a Φ35×103 mm fully welded structure liquid aluminum electrolytic capacitor semi-finished product; (5) The cylindrical liquid aluminum electrolytic capacitor semi-finished product obtained in step (4) and the positive terminal cover are welded together using a laser welding machine, wherein the positive electrode column is located at the center of the positive terminal cover and the positive electrode column and the positive terminal cover are integrally formed. After drying, liquid injection and liquid injection port sealing steps, a Ф35×103 mm fully welded structure liquid aluminum electrolytic capacitor is obtained.

[0055] Example 4 This embodiment provides a method for preparing an aluminum electrolytic capacitor, and the specific steps are as follows: (1) Use a winding machine to wind the anode foil (the laminated foil with a "reinforced concrete structure" at the bottom is 57 mm wide and 250 μm thick; the upper tab is 15 mm wide and 30 μm thick), the main foil and the cathode tab are both 20 μm thick. The cathode foil (main foil width is 57 mm, tab width is 15 mm) and the electrolytic paper (thickness is 30 μm, width is 65 mm) are wound together into a 60×85 mm Φ fully welded structure core package; (2) shaping the anode tabs and cathode tabs extending oppositely from both ends of the 60×85 mm Φ fully welded core package obtained in step (1) using a tab shaping machine and then flattening them to obtain a shaped core package; (3) using a laser welding machine to sequentially weld the cathode tab, negative electrode current collector, and negative terminal cover of the shaped core package obtained in step (2) together, with the negative electrode column located at the center of the negative terminal cover and the negative electrode column and the negative terminal cover being integrally formed, to obtain a pre-treated core package; (4) using an automatic shell-introducing machine to pack the pretreated core package obtained in step (3) into an aluminum shell, using a sealing machine to roll-slot-seal and secondary-mold-seal the negative terminal cover with the aluminum shell through an insulating gasket, and then using a laser welding machine to weld the anode tab and the positive electrode current collector together to obtain a 60×85 mm fully welded structure liquid aluminum electrolytic capacitor semi-finished product; (5) The cylindrical liquid aluminum electrolytic capacitor semi-finished product obtained in step (4) and the positive terminal cover are welded together using a laser welding machine, wherein the positive electrode column is located at the center of the positive terminal cover and the positive electrode column and the positive terminal cover are integrally formed. After drying, liquid injection and liquid injection port sealing steps, a Φ60×85 mm fully welded structure liquid aluminum electrolytic capacitor is obtained.

[0056] Example 5 This embodiment provides a method for preparing an aluminum electrolytic capacitor, and the specific steps are as follows: (1) Use a winding machine to wind the anode foil (the laminated foil with a "reinforced concrete structure" at the bottom is 110 mm wide and 260 μm thick; the upper tab is 15 mm wide and 30 μm thick), the cathode foil (the main foil is 110 mm wide and the tab is 15 mm wide) with the main foil and the cathode tab thickness of 20 μm, and the electrolytic paper (30 μm thick and 118 mm wide) together into a 60×138 mm fully welded core package; (2) shaping the anode tabs and cathode tabs extending oppositely from both ends of the Φ60×138 mm fully welded core package obtained in step (1) using a tab shaping machine and then flattening them to obtain a shaped core package; (3) using a laser welding machine to sequentially weld the cathode tab, negative electrode current collector, and negative terminal cover of the shaped core package obtained in step (2) together, with the negative electrode column located at the center of the negative terminal cover and the negative electrode column and the negative terminal cover being integrally formed, to obtain a pre-treated core package; (4) using an automatic shell-introducing machine to pack the pretreated core package obtained in step (3) into an aluminum shell, using a sealing machine to roll-slot-seal and secondary-mold-seal the negative terminal cover with the aluminum shell through an insulating gasket, and then using a laser welding machine to weld the anode tab and the positive electrode current collector together to obtain a 60×138 mm fully welded structure liquid aluminum electrolytic capacitor semi-finished product; (5) The cylindrical liquid aluminum electrolytic capacitor semi-finished product obtained in step (4) and the positive terminal cover are welded together using a laser welding machine, wherein the positive electrode column is located at the center of the positive terminal cover and the positive electrode column and the positive terminal cover are integrally formed. After drying, liquid injection and liquid injection port sealing steps, a Φ60×138 mm fully welded structure liquid aluminum electrolytic capacitor is obtained.

[0057] Comparative Example 1 This comparative example provides a method for preparing an aluminum electrolytic capacitor, and the specific steps are as follows: (1) Anode foil (obtained by sequentially corroding and anodizing aluminum foil) (width 35 mm, thickness 220 μm) and cathode foil (width 35 mm, thickness 20 μm) prepared by conventional chemical forming process were wound together with electrolytic paper (width 41 mm, thickness 30 μm) into a 22×45 mm welding pin structure core package using a winding machine. During the winding process, the anode foil and cathode foil were riveted with lead strips respectively. After winding, the top of the obtained core package contained a pair of lead strips with a length of 16 mm and a width of 5 mm. (2) The solder pin structure core package obtained in step (1) is vacuum dried and then riveted to a cover plate, and then subjected to liquid injection, sealing, and aging steps in sequence to obtain a 22×45 mm solder pin liquid aluminum electrolytic capacitor.

[0058] Comparative Example 2 This comparative example provides a method for preparing an aluminum electrolytic capacitor, which differs from Example 1 only in that a chemically formed foil is used instead of a laminated foil, wherein the chemically formed foil is prepared by a conventional chemically formed process.

[0059] Comparative Example 3 This comparative example provides a method for preparing an aluminum electrolytic capacitor, and the specific steps are as follows: (1) A winding machine was used to wind the anode foil (laminated foil with a "reinforced concrete structure", with a width of 35 mm and a thickness of 220 μm) and the cathode foil (with a width of 35 mm and a thickness of 20 μm) together with the electrolytic paper (with a thickness of 30 μm and a width of 41 mm) into a 22×45 mm welding pin structure core package. During the winding process, the anode foil and the cathode foil were riveted with lead strips respectively. After winding, the top of the core package contained a pair of lead strips with a length of 16 mm and a width of 5 mm. (2) The solder pin structure core package obtained in step (1) is vacuum dried and then riveted to a cover plate, and then subjected to liquid injection, sealing, and aging steps in sequence to obtain a 22×45 mm solder pin liquid aluminum electrolytic capacitor.

[0060] Test Case The electrical performance of the aluminum electrolytic capacitors prepared in the embodiments and comparative examples was tested, and the results are shown in Table 1.

[0061] Table 1

[0062] It can be seen from the test results in Table 1 that the fully welded cylindrical liquid aluminum electrolytic capacitor prepared according to the scheme of the present invention has high capacity, low internal resistance and low loss. Among them, the aluminum electrolytic capacitor prepared in Example 1 has a smaller size than the aluminum electrolytic capacitors prepared in Examples 2-5, so the capacity is lower, but compared with the aluminum electrolytic capacitors of the same specification prepared in Comparative Examples 1-2, the capacity is still advantageous. In addition, Comparative Example 1 uses anode foil prepared by traditional chemical formation process and assembles cylindrical liquid aluminum electrolytic capacitors according to traditional welding pin structure. Compared with the cylindrical liquid aluminum electrolytic capacitors of the present invention that use anode foil containing lower laminated foil and upper pole ear and are assembled according to a fully welded structure, the product capacity is more than 20% lower and the internal resistance is more than 120% higher. Comparative Example 2 uses anode foil prepared by traditional chemical formation process and assembles cylindrical liquid aluminum electrolytic capacitors according to a fully welded structure. Due to the low product capacity, the internal resistance is relatively large. Comparative Example 3 uses laminated foil with a "reinforced concrete structure" and assembles a cylindrical liquid aluminum electrolytic capacitor according to a traditional welding pin structure. Since there is only one pair of tabs, the product has a high internal resistance, resulting in large losses.

[0063] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0064] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. An aluminum electrolytic capacitor core pack, characterized in that: It includes an anode foil, a cathode foil and electrolytic paper, wherein the electrolytic paper is located between the anode foil and the cathode foil; The anode foil comprises a laminated foil and an anode tab, wherein the anode tab is connected to an edge of the laminated foil, and the laminated foil has a coating, wherein the coating is formed by a composite of three-dimensional porous spherical aluminum powder particles and porous aluminum oxide fibers; The cathode foil comprises a main foil sheet and a cathode tab, wherein the cathode tab is connected to an edge of the main foil sheet; The anode foil, electrolytic paper and cathode foil are wound to form the aluminum electrolytic capacitor core pack, and the anode tab and cathode tab are respectively located at two ends of the aluminum electrolytic capacitor core pack.

2. The aluminum electrolytic capacitor core pack according to claim 1, characterized in that: The widths of the anode foil and the cathode foil are the same.

3. The aluminum electrolytic capacitor core pack according to claim 2, characterized in that: The build-up foil and the main foil have the same width.

4. The aluminum electrolytic capacitor core pack according to claim 3, characterized in that: The laminated foil has a thickness of 201-300 μm and a width of 35-110 mm; The main foil has a thickness of 10-30 μm and a width of 35-110 mm.

5. The aluminum electrolytic capacitor core pack according to claim 3, characterized in that: The anode tab has a thickness of 20-60 μm and a width of 6-15 mm; The cathode tab has a thickness of 10-30 μm and a width of 6-15 mm.

6. The aluminum electrolytic capacitor core pack according to claim 1, characterized in that: The base material of the laminated foil includes plain foil.

7. The aluminum electrolytic capacitor core pack according to claim 1, characterized in that: The material of the anode tab and / or cathode tab includes plain foil or etched foil.

8. The aluminum electrolytic capacitor core pack according to claim 1, characterized in that: The material of the main foil includes plain foil or corroded foil.

9. An aluminum electrolytic capacitor, characterized in that: The invention comprises an aluminum electrolytic capacitor core pack as described in any one of claims 1 to 8.

10. The aluminum electrolytic capacitor according to claim 9, characterized in that: It also includes a metal shell, a positive current collector, a negative current collector, a positive terminal cover, a negative terminal cover, a positive pole column, and a negative pole column; Wherein, the cathode tab, the negative electrode current collector, the negative electrode terminal cover and the negative electrode column are connected in sequence; The anode tab, the positive current collector, the positive terminal cap and the positive electrode column are connected in sequence; The aluminum electrolytic capacitor core package is located in the metal shell.

11. The aluminum electrolytic capacitor according to claim 9, characterized in that The aluminum electrolytic capacitor has a diameter of 22-60 mm and a height of 45-138 mm.

12. A method for preparing an aluminum electrolytic capacitor according to any one of claims 9 to 11, characterized in that: include: The anode foil, cathode foil and electrolytic paper are wound to form an aluminum electrolytic capacitor core pack, and the anode tab and cathode tab are respectively located at two ends of the aluminum electrolytic capacitor core pack.

13. The preparation method according to claim 12, characterized in that: Also includes: Performing tab shaping on the aluminum electrolytic capacitor core package to obtain a shaped core package; The shaped core package is placed in a metal shell, and the cathode tab, negative current collector, negative terminal cover, and negative pole of the shaped core package are connected in sequence; and the anode tab, positive current collector, positive terminal cover, and positive pole of the shaped core package are connected in sequence.

14. The preparation method according to claim 13, characterized in that: Also includes: Connecting the cathode tab to the negative electrode current collector, and connecting the anode tab to the positive electrode current collector; The negative terminal cover is integrally formed with the negative electrode column and connected to the negative electrode current collector, and the negative terminal cover seals a port of the metal shell through an insulating gasket; The positive terminal cover is integrally formed with the positive electrode column and is connected to the positive electrode current collector and another port of the metal shell in sequence.

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