CN113488337A

CN113488337A - Novel laminated polymer aluminum electrolytic capacitor and manufacturing method thereof

Info

Publication number: CN113488337A
Application number: CN202110767339.4A
Authority: CN
Inventors: 张彩欣
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-07-07
Filing date: 2021-07-07
Publication date: 2021-10-08

Abstract

The invention discloses a novel laminated polymer aluminum electrolytic capacitor and a manufacturing method thereof, wherein the manufacturing method comprises the following steps: the capacitor is internally provided with a laminated structure of single-layer or multi-layer cores, each layer of capacitor core is provided with an aluminum foil and is divided by a barrier material to form an anode and a cathode; the aluminum foil of the anode comprises an aluminum core or an aluminum core covered with an aluminum oxide film; the cathode is sequentially provided with an aluminum core covered with an aluminum oxide film, a conductive polymer layer, a non-metal conductive layer and a metal conductive layer; the metal conducting layer is connected with the cathode lead-out terminal through a conducting material, and all structures of the inner core of the capacitor except the anode aluminum foil cut part and the cathode lead-out terminal cut part are covered by an insulating material to form an insulating protective shell; the surfaces of the anode aluminum foil notch and the cathode lead-out terminal notch are covered with metal layers, and the metal layers extend along the side surface of the insulating protective shell to cover partial upper and lower surfaces or partial lower surface of the insulating protective shell so as to form an electrode terminal which can be welded on the upper plate and the lower surface or both the upper and lower surfaces.

Description

Novel laminated polymer aluminum electrolytic capacitor and manufacturing method thereof

Technical Field

The invention belongs to the technical field of aluminum electrolytic capacitors, and particularly relates to a novel laminated polymer aluminum electrolytic capacitor and a manufacturing method thereof.

Background

The capacitor is an element capable of storing electric charges, and the capacitor, the resistor and the inductor are three basic elements in a circuit, are essential basic elements in an electronic circuit, and account for about 45% of the using amount of all electronic components. The aluminum electrolytic capacitor occupies more than 30% of the market share of the capacitor due to the excellent performance and low price. In short term, the aluminum electrolytic capacitor does not have the possibility of being completely replaced, and will continue to play an important role in the fields of automobile electronics, communication, internet of things, artificial intelligence, security monitoring, consumer electronics, new energy, national defense war industry and the like in the future.

In recent years, with the rapid development of 5G smart phones, internet of things, new communication technologies and new energy automobiles, active chips have been rapidly developed, and aluminum electrolytic capacitors as passive elements are correspondingly developed in the directions of thinning, miniaturization, large capacity, low Equivalent Series Resistance (ESR), low leakage current, high reliability and the like. The conventional liquid aluminum electrolytic capacitor cannot satisfy the requirements of thinning and miniaturization in particular, and therefore, the laminated polymer aluminum electrolytic capacitor has been rapidly developed in recent years as a solution for thinning and miniaturization.

The traditional laminated polymer aluminum electrolytic capacitor adopts a lead frame as leading-out terminals of an anode and a cathode and pins welded by a patch, and the capacitor cannot be thinned further. Therefore, how to design a laminated polymer aluminum electrolytic capacitor with a novel structure, namely, the capacitor is further thinned, the using amount of lead frame materials is reduced, the capacitor core inside the insulating protective shell can be ensured to keep good electric contact with an electrode terminal, the good sealing property of the insulating protective shell is ensured, the equivalent series resistance of the capacitor is reduced, the product performances such as reliability and the like are improved, and the laminated polymer aluminum electrolytic capacitor becomes a technical problem which is urgently solved.

Disclosure of Invention

It is an object of the present invention to provide a novel laminated polymer aluminum electrolytic capacitor to solve the above-mentioned problems in the background art.

A novel laminated polymer aluminum electrolytic capacitor comprising: the capacitor is internally provided with a laminated structure of single-layer or multi-layer cores, each layer of capacitor core 1 is provided with an aluminum foil and is divided by a barrier material 12 to form an anode 11 and a cathode 13; the aluminum foil 11 of the anode is an aluminum core containing an aluminum core or an aluminum core covered with an aluminum oxide film; the cathode 13 is formed by sequentially covering a conductive polymer layer 132, a non-metal conductive layer 133 and a metal conductive layer 134 on the surface of an aluminum core 131 with an aluminum oxide film on the surface; the metal conducting layer 134 is connected with the cathode lead-out terminal 3 through the conducting material 2, and all structures inside the capacitor except the cut of the anode aluminum foil 11 and the cut of the cathode lead-out terminal 3 are covered by the insulating material to form an insulating protective shell 4; the surface of the cut of the anode aluminum foil 11 and the cut of the cathode lead-out terminal 3 are covered with a metal layer 5, and the metal layer 5 extends along the side surface of the insulating protective shell to cover partial upper and lower surfaces or partial lower surface of the insulating protective shell so as to form an electrode terminal which can be welded on the upper plate and the lower surface or both the upper plate and the lower surface.

The cathode lead-out terminal is at least one of a sheet shape, a foil shape, a block shape, a net shape and a foam shape; the cathode lead-out terminal is at least one selected from copper, silver-coated copper, gold, tin, aluminum, nickel, zinc, platinum, graphite, graphene and carbon, and is preferably copper; the cathode lead terminal is optionally a copper sheet, copper foil, copper mesh, nickel foam, graphite sheet, or the like, more preferably a copper foil. The conductive material is at least one selected from copper, silver-coated copper, gold, tin, aluminum, nickel, zinc, platinum, graphite, graphene, silver-coated copper, carbon and niobium monoxide, preferably silver, and more preferably silver paste.

The conductive polymer layer is selected from at least one of polypyrrole and derivatives thereof, polythiophene and derivatives thereof, polyaniline and derivatives thereof, preferably at least one of polypyrrole, poly (3, 4-ethylenedioxythiophene) and polyaniline, and the thickness of the conductive polymer layer is preferably 0.01 mm-0.2 mm. The non-metal conducting layer is selected from at least one of graphite, graphene, carbon and niobium monoxide, and preferably at least contains graphite; preferably, the thickness is 0.01 mm-0.1 mm. The metal conducting layer is selected from at least one of copper, silver-coated copper, gold, tin, aluminum, nickel, zinc and platinum, and preferably at least contains silver; preferably, the thickness is 0.01 mm-0.2 mm. The metal layer is selected from at least one of copper, silver-coated copper, gold, tin, aluminum, nickel, zinc and platinum; preferably, the metal layer comprises at least two different metal layers, preferably a copper layer and a tin layer on the surface of the copper layer in sequence; more preferably a copper layer, a nickel layer on the surface of the copper layer and a tin layer on the surface of the nickel layer in this order.

The invention also aims to provide a manufacturing method of the novel laminated polymer aluminum electrolytic capacitor, which comprises the following steps:

step S1: dividing the aluminum foil into an anode and a cathode by using a barrier material, and sequentially preparing a conductive polymer layer, a non-metallic conductive layer and a metal conductive layer on the surface of the cathode aluminum foil to form a single-layer capacitor core with an anode and cathode structure;

step S2: the anode of the capacitor core corresponds to the anode, the cathode of the capacitor core corresponds to the cathode and the cathode leading-out terminal for lamination, and the metal conducting layer is connected with the cathode leading-out terminal and the metal conducting layer by conducting materials to prepare a laminated structure of a single-layer or multi-layer core; the number of the cathode leading-out terminals is 1 or more;

step S3: covering the capacitor core with an insulating material to form an insulating protective shell; all the structures in the capacitor except a part of the anode and a part of the cathode lead-out terminals are covered by insulating materials;

step S4: removing part of the anode, part of the cathode leading-out terminal and part of the insulating protective shell;

step S5: and covering metal layers on the surfaces of the anode aluminum foil notch and the cathode leading-out terminal notch, wherein the metal layers cover partial upper and lower surfaces or partial lower surfaces of the insulating protective shell, and preparing the capacitor.

The external dimension of the product refers to the external dimension of the capacitor, for example, the external length of a V-shell capacitor is generally 7.3mm, the external width is 4.3mm, and the external height is 1.8 mm. In the step S1, the anode is exposed from the insulating protective housing at the anode end and electrically connected to the metal layer at the anode end, the length of the anode is 5% to 100% of the external length of the product, and optionally the length of the anode is 5%, 10%, 15%, 20%, 30%, 40%, 50%, 60%, 70%, 80% of the external length of the product. The area of the cathode is in direct proportion to the capacity of the capacitor, and the length of the cathode is required to be as large as possible in order to improve the specific capacity of the capacitor; the cathode length is 40% to 98% of the product form length, optionally 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 98% of the product form length, preferably 70% to 95% of the product form length.

The conductive polymer layer is selected from at least one of polypyrrole and derivatives thereof, polythiophene and derivatives thereof, polyaniline and derivatives thereof, preferably at least one of polypyrrole, poly (3, 4-ethylenedioxythiophene) and polyaniline, and the thickness of the conductive polymer layer is preferably 0.01 mm-0.2 mm.

The non-metal conducting layer is selected from at least one of graphite, graphene, carbon and niobium monoxide, and preferably at least comprises graphite; optionally, the material is prepared by solidifying graphite slurry and graphene/graphene composite slurry. Preferably, the thickness of the cured non-metal conducting layer is 0.01 mm-0.1 mm.

The metal conductive layer is selected from at least one of silver, silver-coated copper, gold, tin, aluminum, nickel, zinc and platinum, and preferably at least comprises silver; and optionally adopting silver paste and silver-clad copper paste for curing.

Preferably, the thickness of the cured metal conductive layer is 0.01 mm-0.1 mm.

In step S2, the length of the cathode lead-out terminal is 3% to 200% of the external length of the product, and optionally the length of the cathode lead-out terminal is 3%, 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, 120%, 140%, 160%, 180%, 200% of the external length of the product. The length of the overlapped part of the cathode lead-out terminal and the metal conductive layer is 1% -100% of the length of the cathode, optionally the length of the overlapped part of the cathode lead-out terminal and the metal conductive layer is 1%, 3%, 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100% of the length of the cathode, and preferably the length of the overlapped part of the cathode lead-out terminal and the metal conductive layer is 3% -60% of the length of the cathode. In order to ensure that the electrical contact between the notch of the cathode terminal and the metal layer is good and the thickness of the capacitor is not influenced remarkably, the width of the cathode lead-out terminal is 5% -95% of the external width of the product; the thickness of the cathode lead-out terminal is 0.001mm to 0.1mm, optionally 0.001mm, 0.003mm, 0.005mm, 0.008mm, 0.01mm, 0.02mm, 0.03mm, 0.04mm, 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm, 0.1mm, preferably 0.005mm to 0.05 mm. Preferably, the length of the anode is 0% -100% of the requirement of the external length dimension of the product.

In step S2, the conductive material is at least one selected from copper, silver-coated copper, gold, tin, aluminum, nickel, zinc, platinum, graphite, graphene, carbon, and niobium monoxide, preferably silver, and more preferably a silver paste. The cathode lead-out terminal is at least one of a sheet shape, a foil shape, a block shape, a net shape and a foam shape; the cathode lead terminal is at least one selected from copper, silver-coated copper, gold, tin, aluminum, nickel, zinc, platinum, graphite, graphene, carbon and niobium monoxide, preferably copper; the cathode lead terminal is optionally a copper sheet, copper foil, copper mesh, nickel foam, graphite sheet, or the like, more preferably a copper foil. Preferably, the curing is carried out after lamination, wherein the curing comprises airing, drying or combination of the airing and the drying, and the drying is carried out at the temperature of 40-300 ℃ for 0.01-2 h.

Step S3 is further configured to: the insulating material of the insulating protective shell is at least one selected from epoxy resin, polyurethane resin, phenolic resin, alkyd resin, polyester resin, amino resin, acrylic resin, organic silicon resin, hydrocarbon resin, chlorinated rubber, fluorine-based polymer, vinyl-based resin, polyimide resin, ceramic or inorganic/high-molecular composite material. In the step S3, part of the anode aluminum foil is exposed out of the insulating protective housing, and part of the cathode lead-out terminal is exposed out of the insulating protective housing;

in the step S4, at least one of laser cutting, cutter cutting, grinding, shot blasting and sand blasting is adopted to remove part of the anode, part of the cathode leading-out terminal and part of the insulating protective shell, and the length of the anode and the cathode leading-out terminal outside the insulating protective shell after removal is 0-0.1 mm. The first purpose is to expose the anode cut and the cut of the cathode lead-out terminal outside the insulating protective case so as to be electrically connected with the metal layers of the anode terminal and the cathode terminal; another object is to make the overall external size of the capacitor not exceed the external size.

Step S5 is further configured to: the metal layer is selected from at least one of copper, silver-coated copper, gold, tin, aluminum, nickel, zinc and platinum; the metal layer is covered by chemical plating, electroplating, physical sputtering, physical deposition, chemical deposition, spraying, coating, spraying, printing and other methods. Preferably, the metal layer comprises at least two different metal layers, preferably a copper layer and a tin layer on the surface of the copper layer in sequence; more preferably a copper layer, a nickel layer on the surface of the copper layer and a tin layer on the surface of the nickel layer in this order. More specifically, physical sputtering or physical deposition is adopted to prepare a copper layer on the anode notch and the notch of the cathode lead-out terminal and the nearby position, and then a nickel layer and a tin layer are prepared on the surface of the copper layer through electroplating or chemical plating to be used as electrode terminals capable of being pasted and welded on the upper plate. In order to maintain good conductivity and solderability, the metal layer preferably has a thickness of 0.3 μm to 60 μm, optionally 0.3 μm, 1.0 μm, 3.0 μm, 5.0 μm, 8.0 μm, 10.0 μm, 15.0 μm, 20.0 μm, 25.0 μm, 30.0 μm, 35.0 μm, 40.0 μm, 45.0 μm, 50.0 μm, 55.0 μm, 60.0 μm, preferably 3.0 μm to 20 μm.

In order to prepare the capacitor with the surface capable of being pasted with the chip, the metal layer at least covers the anode notch, the side surface connected with the anode notch and part of the lower surface, the cathode lead-out terminal notch, the side surface connected with the cathode lead-out terminal notch and part of the lower surface; in order to manufacture the capacitor with the upper surface and the lower surface both capable of being pasted with the chip, the metal layer at least covers the anode notch, the side surface connected with the anode notch, part of the upper surface and the lower surface, the cathode lead-out terminal notch, the side surface connected with the cathode lead-out terminal notch and part of the upper surface and the lower surface. The length of the lower surface or part of the upper and lower surfaces of the insulating protection shell part covered by the metal layer is 5% -45% of the external length of the product, optionally 5%, 8%, 10%, 12%, 16%, 20%, 25%, 30%, 35%, 40%, 45% of the external length of the product, and preferably 10% -25% of the external length of the product; the width of the lower surface or part of the upper and lower surfaces of the insulating protective housing part covered by the metal layer is 5% -100% of the width of the product exterior, optionally 5%, 15%, 25%, 35%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 100% of the width of the product exterior, and preferably 50% -90% of the width of the product exterior. According to the invention, the novel structure is adopted to remove the traditional lead frame material, so that the use of the traditional lead frame material is greatly reduced, the waste of resources is reduced, the integral thickness of the product is reduced, the effective area of the cathode of the internal capacitor is increased, and the product capacity is increased. In addition, the invention can prepare products with traditional large size and products with extremely micro size which can not be related by the traditional method, and the products have the advantages of low leakage current, low equivalent series resistance, better high temperature and high humidity resistance, better ripple current resistance and the like.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is an overall schematic view of a capacitor core of each layer according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of the cathode and anode division of each layer of capacitor core according to the embodiment of the present invention.

FIG. 3 is a schematic view of the cathode composition of each layer of the capacitor core according to the embodiment of the present invention.

Fig. 4 is a schematic view of an overall structure of a thirty-two product according to the first embodiment, the fourth embodiment, the fifth embodiment and the seventh embodiment of the present invention.

Fig. 5 is a schematic view of the overall structure of a second product according to an embodiment of the present invention.

Fig. 6 is a schematic view of the overall structure of a third product according to an embodiment of the present invention.

Fig. 7 is a schematic diagram of the overall structure of a sixth product according to an embodiment of the present invention.

FIG. 8 is an overall schematic view of the capacitor core of each layer of this comparative example.

FIG. 9 is a schematic diagram showing the division of the cathode and anode of each capacitor element of comparative example.

FIG. 10 is a schematic view showing the composition of the cathode of each layer of the capacitor core of comparative example

FIG. 11 is a schematic diagram of the overall structure of comparative example I, comparative example V, and comparative example seven-comparative example thirty-two products.

Fig. 12 is a schematic view of the overall structure of the comparative example product.

Fig. 13 is a schematic diagram of the overall structure of the third comparative example and the sixth comparative example.

Reference numerals indicate the same.

1 single layer capacitor core.

2 conductive material.

And 3, a cathode lead-out terminal.

4 insulating protective shell.

5 a metal layer.

11 an anode.

12 barrier material.

13 cathode.

131 are covered with an aluminium core of aluminium oxide film.

132 a conductive polymer layer.

133 non-metallic conductive layer

134 metal conductive layer.

100 single layer capacitor core

200 anodic bonding

300 of electrically conductive material.

400 cathode lead-out terminal.

500 insulating protective housing.

600 anode lead-out terminal.

110 anode.

120 barrier material.

130 cathode.

1310 an aluminum core covered with an aluminum oxide film.

1320 a conductive polymer layer.

1330 a non-metallic conductive layer.

1340 a metal conducting layer.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail with reference to the accompanying drawings and embodiments, it being understood that the specific embodiments described herein are only for the purpose of explaining the present invention and are not intended to limit the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that unless otherwise explicitly stated or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; the two elements may be directly connected or indirectly connected through an intermediate medium, or may be communicated with each other inside the two elements, or may be wirelessly connected or wired connected. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Furthermore, the technical features mentioned in the different embodiments of the present invention described above may be combined with each other as long as they do not conflict with each other.

Example one

Step S1: the aluminum foil is divided into an anode 11 and a cathode 13 by using a barrier material 12, a poly 3, 4-ethylenedioxythiophene layer is sequentially prepared on the surface of the aluminum foil 131 of the cathode 13 to serve as a conductive polymer layer 132, a graphite layer is prepared on the surface of the conductive polymer layer 132 by using graphite slurry to serve as a non-metal conductive layer 133, a silver layer is prepared on the surface of the non-metal conductive layer 133 by using silver slurry to serve as a metal conductive layer 134, and the single-layer capacitor core 1 is prepared. Wherein, the external length of the capacitor is 7.3mm, the external width of the capacitor is 4.3mm, the length of the anode is 5.1mm (70% of the external length of the product), and the length of the cathode is 6.57mm (90% of the external length of the product); the aluminum foil is an aluminum core with the surface containing an aluminum oxide film, the average thickness of the poly 3, 4-ethylenedioxythiophene layer is 0.05mm, the average thickness of the graphite layer is 0.02mm, and the average thickness of the silver layer is 0.08 mm.

Step S2: and (3) corresponding the anode 11 and the anode 11 of the 2-layer capacitor core prepared in the step (S1), sequentially and correspondingly laminating the cathode 13, the 1 cathode lead-out terminal and the cathode 13, bonding the cathode 13 by using silver paste, and drying the laminate at 100 ℃ for 1h for curing to prepare the capacitor core with the laminated structure. The cathode lead-out terminal 3 is a copper foil, the average thickness of the copper foil is 0.005mm, the length of the copper foil is 10.2mm (140% of the external length of the product), the width of the copper foil is 3.87mm (90% of the external width of the product), and the length of the copper foil overlapped with the cathode layer is 80% of the length of the cathode layer.

Step S3: except for a part of the anode 11 and a part of the cathode leading-out terminal 3, the inside of the capacitor is covered by insulating material epoxy resin to form an insulating protective shell 4; the length of the anode aluminum foil 11 exposed out of the insulating protective housing 4 after covering is 4.9mm (namely 67.1% of the external length dimension of the product), and the length of the cathode lead-out terminal 3 exposed out of the insulating protective housing 4 is 4.8mm (namely 65.7% of the external length dimension of the product).

Step S4: the excess anode 11, cathode lead-out terminal 3 and insulating protective case 4 were removed by laser cutting, and after removal, the average length of the anode 11 and cathode lead-out terminal 3 outside the insulating protective case was 0.05 mm.

Step S5: in the cut of the anode 11 exposed out of the insulating protective case and the cut of the cathode lead-out terminal 3 exposed out of the insulating protective case and the periphery thereof, a copper layer having an average thickness of 0.5 μm is prepared by a sputtering method, and then a tin layer having an average thickness of 4.5 μm is coated on the surface of the copper layer by an electroplating method to prepare a metal layer 5. The metal layer 5 covers most of the side surface of the insulating protective case 4, and covers part of the upper surface and the lower surface of the insulating protective case 4, the length of the upper surface and the lower surface of the covering protective case is 1.46mm (20% of the external length of the product), and the width of the covering protective case is 4.08mm (95% of the external width of the product), so as to form electrode terminals, the upper surface and the lower surface of which can be welded by upper plate patches. The novel laminated polymer aluminum electrolytic capacitor shown in figure 4 is prepared, and the external dimension of the capacitor is 7.3mm in length, 4.3mm in width and 1.1mm in height.

Example two

As shown in fig. 5, the number of stacked layers is one, the cathode lead-out terminal 3 is gold foil, the conductive material 2 is gold paste, the non-metal conductive layer 133 is a graphene-based paste layer, the insulating material of the insulating protective housing 4 is polyurethane resin, and the metal layer 5 covers the side surface of the insulating protective housing 4 and covers the lower surface of the insulating protective housing 4 by 1.4mm (19.2% of the overall length of the product) to form an electrode terminal that can be subjected to upper plate patch welding on the lower surface.

EXAMPLE III

A novel laminated polymer aluminum electrolytic capacitor and a method for manufacturing the same are disclosed, as shown in FIG. 6,

the number of laminated layers is three, the cathode lead-out terminal 3 is silver foil, the conductive material 2 is copper paste, the non-metal conductive layer 133 is a carbon fiber layer, the insulating material of the insulating protective shell 4 is polyimide resin, the metal layer 5 is a three-layer structure, a copper layer with the thickness of 0.5 μm is covered by a sputtering method, a nickel layer with the thickness of 1 μm is covered by an electroplating method, and a tin layer with the thickness of 5 μm is covered by an electroplating method.

Example four

Step S1: the aluminum foil is divided into an anode 11 with the length of 0.1mm (namely 5% of the requirement of the external length dimension of a product) and a cathode 13 with the length of 0.08mm (namely 40% of the external length of the product) by using a barrier material 12, a polypyrrole layer is prepared on the surface of the aluminum foil 131 of the cathode 13 to serve as a conductive polymer layer 132, a non-metal conductive layer 133 is prepared on the surface of the conductive polymer layer 132 by adopting graphite slurry, a metal conductive layer 134 is prepared on the surface of the non-metal conductive layer 133 by adopting silver-coated copper slurry, and the single-layer capacitor core 1 is prepared. The polypyrrole layer 132 has an average thickness of 0.01mm, the non-metal conductive layer 133 has an average thickness of 0.01mm, and the metal conductive layer 134 has an average thickness of 0.01 mm.

Step S2: correspondingly laminating an anode 11 and an anode 11 of 2 layers of capacitor cores, and a cathode 13, and bonding the cathodes 13 of two capacitor cores 1 and a cathode lead-out terminal 3 by using solder paste to form the capacitor core with a laminated structure; the cathode lead-out terminal 3 is a copper foil, the average thickness is 0.001mm, the length is 0.06mm (3% of the external length of the product), the width is 0.063 mm (5% of the external width of the product), and the length of the cathode layer overlapped with the cathode layer is 30% of the length of the cathode layer.

Step S3: all the structures inside the capacitor except for part of the anode 11 and part of the cathode lead-out terminal 3 are covered with an insulating material to form an insulating protective case 4; after covering, the length of the anode aluminum foil 11 exposed out of the insulating protective housing 4 is 0mm (i.e. 0% of the product exterior length), and the length of the cathode lead-out terminal 3 exposed out of the insulating protective housing 4 is 0mm (i.e. 0% of the product exterior length).

Step S4: the excess anode 11, cathode lead-out terminal 3 and insulating protective case 4 were removed, and the average length of the anode 11 and cathode lead-out terminal 3 exposed to the insulating protective case after removal was 0 mm.

Step S5: in the part of the anode 11 and the cathode lead-out terminal 3 exposed out of the insulating protective shell and the periphery thereof, a copper layer with the average thickness of 0.1 μm is prepared by vapor deposition, and then a tin layer with the thickness of 0.2 μm is covered on the surface of the copper layer by an electroplating method to prepare the metal layer 5. The metal layer 5 covers most of the side surface of the insulation protection housing 4, covers part of the upper surface and the lower surface of the insulation protection housing 4, covers the upper surface and the lower surface, has a length of 0.1mm (5% of the overall length of the product) and a width of 0.0625mm (5% of the overall width of the product), and forms electrode terminals with upper and lower surfaces capable of being subjected to board patch welding.

Through the above steps, a novel laminated polymer aluminum electrolytic capacitor as shown in fig. 4 is obtained, wherein the external dimension of the capacitor is 2mm in length, 1.25mm in width and 0.8mm in height.

EXAMPLE five

Step S1: the aluminum foil is divided into an anode 11 with the length of 7.3mm (namely 100% of the requirement of the external length dimension of a product) and a cathode 13 with the length of 6.935mm (namely 95% of the requirement of the external length dimension of the product) by using a barrier material 12, a polyaniline layer is prepared on the surface of the aluminum foil 131 of the cathode 13 to serve as a conductive polymer layer 132, a non-metal conductive layer 133 is prepared on the surface of the conductive polymer layer 132 by using graphite slurry, a metal conductive layer 134 is prepared on the surface of the non-metal conductive layer 133 by using silver slurry, and the single-layer capacitor core 1 is prepared. The average thickness of the polyaniline layer is 0.2mm, the average thickness of the non-metal conductive layer 133 is 0.1mm, and the average thickness of the metal conductive layer 134 is 0.2 mm.

Step S2: correspondingly laminating an anode 11 and an anode 11 of 2 layers of capacitor cores, and a cathode 13, and bonding the cathodes 13 of two capacitor cores 1 and a cathode lead-out terminal 3 by using silver paste to form the capacitor core with a laminated structure; the cathode lead-out terminal 3 is made of foam nickel, the average thickness is 0.05mm, the length is 14.6mm (200% of the external length and size of the product), the width is 5.795mm (95% of the external width and size of the product), and the length of the cathode layer overlapped with the cathode layer is 100% of the length of the cathode layer.

Step S3: except for a part of the anode 11 and a part of the cathode leading-out terminal 3, all the internal structures are covered by an insulating material inorganic/polymer composite material to form an insulating protective shell 4; the length of the anode aluminum foil 11 exposed out of the insulating protective housing 4 after covering is 7.3mm (i.e. 100% of the product exterior length dimension requirement), and the length of the cathode lead-out terminal 3 exposed out of the insulating protective housing 4 is 12.41mm (i.e. 170% of the product exterior length dimension requirement).

Step S4: the extra anode 11, cathode lead-out terminal 3 and insulating protective case 4 were removed, and after removal, the length of anode 11 and cathode lead-out terminal 3 outside the insulating protective case was 0.1 mm.

Step S5: in the anode notch, the cathode lead-out terminal notch and the periphery thereof, a copper layer with an average thickness of 5 μm is prepared by a sputtering method, and then a tin layer with a thickness of 55 μm is coated on the surface of the copper layer by a coating method to prepare a metal layer 5. The metal layer 5 covers most of the side surface of the insulating protective case 4, and covers part of the upper surface and the lower surface of the insulating protective case 4, the length of the upper surface and the lower surface is 3.285mm (45% of the requirement of the product exterior length dimension), the width is 6.1mm (100% of the requirement of the product exterior width dimension), and electrode terminals with upper and lower surfaces capable of being welded by upper plate patches are formed.

Through the above steps, a novel laminated polymer aluminum electrolytic capacitor as shown in fig. 4 is obtained, and the external dimensions of the capacitor are 7.3mm in length, 6.1mm in width and 3.5mm in height.

EXAMPLE six

A novel laminated polymer aluminum electrolytic capacitor and a method for manufacturing the same are disclosed, as shown in FIG. 7,

the same as example three except that the number of the cathode lead-out terminals 3 was 2.

Examples seven to ten

A novel laminated polymer aluminum electrolytic capacitor and a manufacturing method thereof are the same as the first embodiment except that the thicknesses of cathode leading-out terminals are respectively adjusted to be 0.001mm, 0.01mm, 0.05mm and 0.1 mm.

Examples eleven to sixteen

A novel laminated polymer aluminum electrolytic capacitor and a manufacturing method thereof are the same as the first embodiment except that the overlapping length of a cathode lead-out terminal and a cathode layer is respectively adjusted to be 1%, 3%, 20%, 40%, 60% and 100% of the length of the cathode layer.

Examples seventeen to twenty

A novel laminated polymer aluminum electrolytic capacitor and a manufacturing method thereof are the same as the first embodiment except that the lengths of cathodes are respectively adjusted to be 40%, 70%, 80% and 95% of the external length of the capacitor.

Examples twenty-one to twenty-five

A novel laminated polymer aluminum electrolytic capacitor and a manufacturing method thereof are provided, which is the same as the first embodiment except that the average thickness of the copper layer in the metal layer is 1 μm, 2 μm, 3 μm, 4 μm, 5 μm in step S5.

Examples twenty-six to thirty-two

A new laminated polymer aluminum electrolytic capacitor and its manufacturing method are disclosed, except that the average thickness of the nickel layer in the metal layer of step S5 is 2 μm, 10 μm, 15 μm, 20 μm, 30 μm, 40 μm, 50 μm, respectively, the rest are the same as the first embodiment.

Testing of capacitors

And testing the capacity, ESR, leakage current, ripple current resistance, durability assessment and steady-state wet and heat performance of the capacitor according to national standards GB/T6346.25-2018 and GB/T6346.2501-2018. The capacitance is tested by a digital bridge LCR at the frequency of 120Hz, and the ESR is tested at the frequency of 1 kHz; and testing the leakage current by using a leakage current tester. The durability is that the capacitor is checked in a 105 ℃ temperature environment by applying rated voltage; the steady-state damp heat is used for examining the capacitor under the environment with the temperature of 60 ℃ and the humidity of 90RH percent.

Comparative examples one to six are conventional laminated polymer aluminum electrolytic capacitors, wherein the single-layer capacitor core is prepared in the same process as the present invention, the lamination process uses conventional lead frame materials as the cathode lead-out terminal 400 and the anode lead-out terminal 600, the lead frame is covered with a metal layer (the metal layer is the same as the present invention), the anode lead-out terminal 600 is connected with the anode aluminum foil 110 by welding, the insulating material is covered after lamination to form an insulating protective shell, and no excess material is removed after the insulating material is covered; except comparative example four, which could not be prepared by conventional methods, the nominal product height was greater than the corresponding examples, and the product form length and form width were equal to the corresponding examples. The performance comparison ratios of the laminated polymer aluminum electrolytic capacitors prepared in examples one to thirty-two and comparative examples one to thirty-two are shown in table 1.

TABLE 1 comparison of Performance of laminated Polymer aluminum electrolytic capacitors

As shown in table 1, compared with the first to thirty-two comparative examples, the novel laminated polymer aluminum electrolytic capacitors prepared by the first to thirty-two methods in the embodiments of the present invention have significantly better performance than the first to thirty-two comparative examples, specifically, smaller size, higher capacity and ripple current resistance, lower ESR and leakage current, and better durability and steady-state wet and heat performance.

In conclusion, the invention has the following beneficial effects: by adopting the novel structure and the preparation method to remove the traditional lead frame material, the use of the traditional lead frame material is greatly reduced, so that the waste of resources is reduced, the integral thickness of a product is reduced, the effective area of the cathode of the internal capacitor is increased, and the product capacity is increased. In addition, the invention can prepare products with traditional large size and products with extremely micro size which can not be related by the traditional method, and the products have the advantages of low leakage current, low equivalent series resistance, better high temperature and high humidity resistance, better ripple current resistance and the like.

It is apparent that the above-described embodiments are only examples for more clearly describing and not limiting the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. All embodiments need not be exemplified, nor can they be exemplified. Obvious changes or modifications can be made without departing from the scope of the invention.

Claims

1. A novel laminated polymer aluminum electrolytic capacitor is characterized in that the inside of the capacitor is provided with a laminated structure of a single-layer core or a plurality of layers of cores;

each layer of capacitor core is provided with an aluminum foil which is divided by a barrier material to form an anode and a cathode;

the aluminum foil of the anode comprises an aluminum core or an aluminum core covered with an aluminum oxide film;

the cathode is sequentially provided with an aluminum core covered with an aluminum oxide film, a conductive polymer layer, a non-metal conductive layer and a metal conductive layer;

the metal conducting layer is connected with the cathode leading-out terminal through a conducting material, and all structures of the core in the capacitor except the anode aluminum foil cut part and the cathode leading-out terminal cut part are covered by an insulating material to form an insulating protective shell;

the anode aluminum foil notch and the cathode leading-out terminal notch are covered with metal layers, and the metal layers extend along the side face of the insulating protection shell to cover partial upper and lower surfaces or partial lower surface of the insulating protection shell.

2. The novel laminated polymer aluminum electrolytic capacitor as claimed in claim 1, wherein the cathode lead-out terminal is at least one of a sheet, a foil, a block, a net and a foam;

the cathode lead-out terminal is selected from at least one of copper, silver-coated copper, gold, tin, aluminum, nickel, zinc, platinum graphite, graphene and carbon, and is preferably copper;

the conductive material is at least one selected from copper, silver-clad copper, gold, tin, aluminum, nickel, zinc, platinum, graphite, graphene, carbon and niobium monoxide, and preferably at least silver.

3. The novel laminated polymer aluminum electrolytic capacitor as claimed in claim 1, wherein the conductive polymer is selected from at least one of polypyrrole and its derivatives, polythiophene and its derivatives, polyaniline and its derivatives;

the non-metal conducting layer is selected from at least one of graphite, graphene, carbon and niobium monoxide, and preferably at least contains graphite;

the metal conductive layer is selected from at least one of copper, silver-coated copper, gold, tin, aluminum, nickel, zinc and platinum, and preferably at least contains silver.

4. The novel laminated polymer aluminum electrolytic capacitor as claimed in claim 1, wherein the metal layer is selected from at least one of copper, silver-coated copper, gold, tin, aluminum, nickel, zinc, and platinum;

preferably, the metal layer comprises at least two different metal layers, preferably a copper layer and a tin layer on the surface of the copper layer in sequence; more preferably a copper layer, a nickel layer on the surface of the copper layer and a tin layer on the surface of the nickel layer in this order.

5. A preparation method of a novel laminated polymer aluminum electrolytic capacitor is characterized by comprising the following steps:

step S5: and covering metal layers on the surfaces of the anode aluminum foil notch and the cathode leading-out terminal notch, wherein the metal layers extend along the side surface of the insulating protective shell to cover partial upper and lower surfaces or partial lower surface of the insulating protective shell, and preparing the capacitor.

6. The method for preparing a novel laminated polymer aluminum electrolytic capacitor as claimed in claim 5, wherein the length of the anode in step S1 is 5% to 100% of the external length of the product, the length of the cathode is 40% to 98% of the external length of the product, and preferably the length of the cathode is 70% to 95% of the external length of the product.

7. The method for manufacturing a novel laminated polymer aluminum electrolytic capacitor as claimed in claim 5, wherein the length of the cathode lead-out terminal in the step S2 is 3% -200% of the external length of the product;

the length of the overlapped part of the cathode leading-out terminal and the metal conducting layer is 1% -100% of the length of the cathode, and preferably the length of the overlapped part of the cathode leading-out terminal and the metal conducting layer is 3% -60% of the length of the cathode;

the width of the cathode leading-out terminal is 5% -98% of the external width of the product;

the thickness of the cathode lead-out terminal is 0.001 mm-0.1 mm, and preferably the thickness of the cathode lead-out terminal is 0.005 mm-0.05 mm.

8. The method for manufacturing a novel laminated polymer aluminum electrolytic capacitor as claimed in claim 5, wherein the insulating material of the insulating protective housing in step S3 is at least one selected from epoxy resin, polyurethane resin, phenolic resin, alkyd resin, polyester resin, amino resin, acrylic resin, silicone resin, hydrocarbon resin, chlorinated rubber, fluorine-based polymer, vinyl resin, polyimide resin, ceramic, and inorganic/polymeric composite material.

9. The method for manufacturing a laminated polymer aluminum electrolytic capacitor as claimed in claim 5, wherein the step S4 is performed by at least one of laser cutting, knife cutting, grinding, shot blasting and sand blasting;

after the removal, the length of the anode outside the insulating protective shell is 0-0.1 mm;

after the removal, the length of the cathode leading-out terminal outside the insulating protection shell is 0-0.1 mm.

10. The method for manufacturing a novel laminated polymer aluminum electrolytic capacitor as claimed in claim 5, wherein the metal layer in step S5 is manufactured by at least one of chemical plating, electroplating, physical sputtering, physical deposition, chemical deposition, spraying, coating, spraying, and printing;

the total thickness of the metal layers is 0.3-60 mu m;

the length of the partial lower surface and/or upper surface insulation protection shell covering the insulation protection shell is 5% -45% of the external length of the product, and preferably 10% -25%;

the width of the part of the lower surface and/or the upper surface of the metal layer covering the insulating protective shell is 5% -100% of the external width of the product, and preferably 50% -90%.