Aluminum wire type polymer capacitor and method for manufacturing the same

Abstract

The application discloses an aluminum wire type polymer capacitor, which comprises a shell and a capacitor body; the capacitor body comprises a stacked aluminum wire structure and a conductive plate, the conductive plate comprises an anode conductive plate and a cathode conductive plate, the stacked aluminum wire structure is provided with an anode area and a cathode area, the anode area of the stacked aluminum wire structure is fixedly connected with the anode conductive plate, and the cathode area of the stacked aluminum wire structure is fixedly connected with the cathode conductive plate; the stacked aluminum wire structure is composed of one or more stacked aluminum wire units; and the stacked aluminum wire unit is composed of a plurality of parallel aluminum wires. By arranging the stacked aluminum wire structure, the aluminum foil structure of a traditional laminated capacitor is replaced, the capacity and the ripple current resistance of the capacitor are greatly improved under the premise of ensuring that the capacitor has a small volume and an equivalent series resistance.

Description

Technical Field

[0001] This invention relates to the field of aluminum electrolytic capacitor technology, and more specifically, to an aluminum wire polymer capacitor and its preparation method. Background Technology

[0002] Conductive polymer multilayer aluminum capacitors, as a novel type of aluminum capacitor, use conductive polymer electrolytes and employ a surface-mount structure design with multi-layer cores connected in parallel and encapsulated and cured in epoxy resin. Compared to traditional aluminum electrolytic capacitors, conductive polymer multilayer aluminum capacitors offer superior performance characteristics such as small size, low leakage current, long lifespan, and good storage stability. However, with the increasingly demanding performance requirements of electronic products, existing conductive polymer aluminum capacitors have gradually revealed their inadequacies in terms of capacitance and equivalent series resistance. Especially in high-frequency, high-current operating environments, higher capacitance is required while simultaneously reducing equivalent series resistance to improve power supply efficiency and ensure system stability.

[0003] Chinese invention patent 201711151480.1 discloses a multilayer capacitor, comprising multiple stacked cells and positive and negative terminals electrically connected to the cells. Each cell includes a positive terminal, a negative terminal, and a shielding wire located between the positive and negative terminals. The negative terminals of each cell are connected together and connected to the negative terminal. The positive terminals of each cell are connected together and connected to the positive terminal. The negative terminal of each cell includes a dielectric film, a solid electrolyte layer, a carbon paste layer, and a silver paste layer sequentially coated on the surface of the positive electrode foil. The outer surface of the multiple cells is encapsulated with an insulating resin layer. The multilayer capacitor also includes an anti-sulfurization protective frame near the negative terminal to prevent sulfur and sulfides in the air from contacting the silver paste layer. Although the above invention patent has good anti-sulfurization effect, the capacitance of this polymer capacitor structure is relatively small and the equivalent series resistance is relatively large, which cannot meet the requirements of high-current operating environments.

[0004] Therefore, there is an urgent need to find a technical solution to further increase the capacity of polymer capacitors while reducing the equivalent series resistance of the capacitors. Summary of the Invention

[0005] Therefore, it is necessary to provide aluminum wire polymer capacitors that are structurally stable, impact-resistant, and have a large capacity to address the aforementioned technical problems.

[0006] To address the aforementioned technical problems, this invention provides an aluminum wire polymer capacitor and its preparation method, employing the following technical solution:

[0007] The first aspect of this invention provides an aluminum wire polymer capacitor, which includes a housing and a capacitor body;

[0008] The capacitor body includes a stacked aluminum wire structure and a conductive plate. The conductive plate includes an anode conductive plate and a cathode conductive plate. The stacked aluminum wire structure is provided with an anode region and a cathode region. The anode region of the stacked aluminum wire structure is fixedly connected to the anode conductive plate, and the cathode region of the stacked aluminum wire structure is fixedly connected to the cathode conductive plate.

[0009] The stacked aluminum wire structure consists of one or more stacked aluminum wire units; each stacked aluminum wire unit consists of several parallel aluminum wires.

[0010] Furthermore, the stacked aluminum wire structure is composed of several stacked aluminum wire units, which are disposed on the front and back sides of the conductive plate, and the number of stacked aluminum wire units on the front and back sides of the conductive plate is the same.

[0011] Furthermore, the stacked aluminum wire structure is composed of a first stacked aluminum wire unit and a second stacked aluminum wire unit, which are disposed on the front and back sides of the conductive plate, forming a sandwich structure with the conductive plate.

[0012] Furthermore, the stacked aluminum wire unit consists of one or more layers of parallel aluminum wires, with each layer of aluminum wires arranged laterally.

[0013] Furthermore, each of the stacked aluminum wire units has the same number of aluminum wire layers and the same arrangement.

[0014] Furthermore, when each layer of aluminum wires is arranged horizontally, a heat dissipation gap is reserved between the aluminum wires, and the heat dissipation gap is 0.2mm to 0.4mm.

[0015] Furthermore, the aluminum wire has an aluminum purity of ≥99.7% and a diameter of 1mm to 3mm.

[0016] Furthermore, the conductive plate includes vertically arranged anode conductive plates and cathode conductive plates, and the stacked aluminum wire unit is provided with an anode area and a cathode area. The anode area of ​​the stacked aluminum wire unit is welded to the anode conductive plate, and the cathode area of ​​the stacked aluminum wire unit is bonded and fixed to the cathode conductive plate.

[0017] Furthermore, the cathode region of the aluminum wire is provided with a conductive polymer layer, a graphite layer, and a silver paste layer from the inside out.

[0018] A second aspect of this invention provides a method for preparing an aluminum wire polymer capacitor, comprising the following steps:

[0019] S1. Prepare aluminum wires and apply insulating glue at the same height on each aluminum wire to form an insulating glue layer. Distinguish the long end of the aluminum wire as the cathode area and the short end as the anode area.

[0020] S2. A conductive polymer layer, a graphite layer, and a silver paste layer are sequentially formed in the cathode region of the aluminum wire.

[0021] S3. Align the anode and cathode areas of several aluminum wires and arrange them horizontally side by side to form a single layer of aluminum wire. Then, stack multiple layers of aluminum wires on the front and back sides of the conductive plate to form a stacked aluminum wire unit. The cathode areas of each layer of aluminum wire and the cathode area of ​​the aluminum wire and the common cathode area are bonded to each other through a layer of silver paste. The anode areas of each layer of aluminum wire and the anode area of ​​the aluminum wire and the common anode area are welded to each other.

[0022] S4. Wrap the insulating tape around the outside of the stacked aluminum wire units on both sides of the common anode region, and fill the gap between the insulating tape and the anode region of the stacked aluminum wire units with an insulating coating to form the capacitor body.

[0023] S5. Encapsulate the capacitor body.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The aluminum wire polymer capacitor provided by this invention significantly improves the capacitance and ripple current withstand capability of the capacitor by setting a stacked aluminum wire structure instead of the aluminum foil structure of traditional multilayer capacitors, while ensuring a smaller capacitor size and equivalent series resistance. By using insulating tape to assist in fixing the anode area of ​​the stacked aluminum wire structure and using the fixing foot structure of the cathode conductive plate to assist in fixing the cathode area of ​​the stacked aluminum wire structure, the vibration resistance of the overall capacitor structure is improved, and the risk of capacitor failure during packaging and use is reduced. Attached Figure Description

[0026] To more clearly illustrate the solutions in this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the aluminum wire polymer capacitor of the present invention;

[0028] Figure 2 This is a schematic diagram of the structure of the capacitor body of the aluminum wire polymer capacitor of the present invention;

[0029] Figure 3 This is a schematic diagram of the structure of the anode conductive plate of the aluminum wire polymer capacitor of the present invention;

[0030] Figure 4 This is a schematic diagram of the structure of the cathode conductive plate of the aluminum wire polymer capacitor of the present invention;

[0031] Figure 5 This is a schematic diagram of the stacked aluminum wire unit of the aluminum wire polymer capacitor of the present invention;

[0032] Figure 6 This is a schematic diagram of the aluminum wire structure of the aluminum wire polymer capacitor of the present invention;

[0033] Figure 7 This is a schematic diagram of the aluminum wire polymer capacitor structure proposed in Embodiment 6 of the present invention;

[0034] Figure 8 This is an exploded view of the aluminum wire polymer capacitor structure proposed in Embodiment 6 of the present invention.

[0035] Explanation of reference numerals in the attached figures:

[0036] Housing 1, upper encapsulation housing 11, lower encapsulation housing 12;

[0037] Cathode conductive plate 2, common cathode area 21, first fixing foot 22, second fixing foot 23, cathode pin 24;

[0038] Stacked aluminum wire structure 3, first stacked aluminum wire unit 31, second stacked aluminum wire unit 32, third stacked aluminum wire unit 33, fourth stacked aluminum wire unit 34, fifth stacked aluminum wire unit 35, sixth stacked aluminum wire unit 36;

[0039] Aluminum wire 301, insulating coating 3011, insulating adhesive layer 3012, conductive polymer layer 3013, graphite layer 3014, silver paste layer 3015, silver paste layer 3016.

[0040] Anode conductive plate 4, common anode region 41, anode pin 42;

[0041] 5. Insulating tape. Detailed Implementation

[0042] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0043] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0044] Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0045] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0046] Example 1

[0047] Please refer to Figures 1 to 6 This embodiment provides an aluminum wire polymer capacitor, which includes a housing 1 and a capacitor body. The housing 1 includes an upper encapsulation shell 11 and a lower encapsulation shell 12. The capacitor body is placed inside the cavity formed by the upper encapsulation shell 1 and the lower encapsulation shell 2, and the capacitor body has a lead structure leading out to the outside of the lower encapsulation shell 2. The lead structure is soldered to an external circuit board to form an electrical connection.

[0048] Furthermore, the capacitor body includes a stacked aluminum wire structure 3 and a conductive plate, such as... Figures 3-4 As shown, the conductive plate includes a vertically arranged anode conductive plate 4 and a cathode conductive plate 2. The stacked aluminum wire structure 3 is provided with an anode area and a cathode area. The anode area of ​​the stacked aluminum wire structure 3 is welded to the anode conductive plate 4, and the cathode area of ​​the stacked aluminum wire structure 3 is bonded to the cathode conductive plate 2.

[0049] The stacked aluminum wire structure 3 consists of one or more stacked aluminum wire units, each of which has an anode region and a cathode region at the same location.

[0050] Specifically, in this embodiment, the stacked aluminum wire structure 3 is composed of a first stacked aluminum wire unit 31 and a second stacked aluminum wire unit 32. The first stacked aluminum wire unit 31 and the second stacked aluminum wire unit 32 are respectively placed on the front and back sides of the conductive plate, forming a sandwich structure with the conductive plate.

[0051] Furthermore, the anode regions of the first stacked aluminum wire unit 31 and the second stacked aluminum wire unit 32 are respectively welded to the front and back surfaces of the anode conductive plate 4, and the cathode regions of the first stacked aluminum wire unit 31 and the second stacked aluminum wire unit 32 are respectively bonded and fixed to the front and back surfaces of the cathode conductive plate 2.

[0052] Furthermore, the pin structure includes an anode pin 42 and a cathode pin 24, with the anode pin 42 extending from the anode conductive plate 4 and the cathode pin 24 extending from the cathode conductive plate 2.

[0053] Specifically, the anode conductive plate 4 includes a sheet-like common anode region 41 and an anode pin 42 extending downward from the middle of the upper end of the common anode region 41 into the encapsulation shell 2. The anode regions of the first stacked aluminum wire unit 31 and the second stacked aluminum wire unit 32 are respectively welded to the front and back surfaces of the common anode region 41.

[0054] Furthermore, the anode pin 42 extends through the lower package 2 and bends into the inside of the capacitor, where it is soldered to the external circuit board.

[0055] Specifically, the cathode conductive plate 2 includes a sheet-like common cathode region 21 and cathode pins 24 extending downward from the middle of the lower end of the common cathode region 21 into the encapsulation shell 2. The cathode regions of the first stacked aluminum wire unit 31 and the second stacked aluminum wire unit 32 are respectively bonded to the front and back surfaces of the common cathode region 21. The cathode pins 24 extend through the encapsulation shell 2 and bend into the inside of the capacitor, where they are soldered to the external circuit board.

[0056] Furthermore, the cathode conductive plate 2 also includes a fixing foot structure, which is used to assist in preventing the stacked aluminum wire structure 3 from becoming loose. The fixing foot structure includes a first fixing foot 22 and a second fixing foot 23 located on the front and back sides of the common cathode region 21, and the first fixing foot 22 and the second fixing foot 23 are side L-shaped fixing feet.

[0057] Specifically, the first fixing foot 22 extends from one side of the common cathode region 21 towards the front of the common cathode region 21 and then bends towards the other side of the extending side to fix the first stacked aluminum wire unit 31 on the front side of the common cathode region 324; the second fixing foot 23 extends from the side corresponding to the extending side of the first fixing foot 22 towards the opposite side of the common cathode region 21 and then bends towards the extending side of the first fixing foot 22 to fix the second stacked aluminum wire unit 32 on the opposite side of the common cathode region 324. Thus, the first fixing foot 22 and the second fixing foot 23 simultaneously fix the first stacked aluminum wire unit 31 and the second stacked aluminum wire unit 32 on both sides of the common cathode region 21, effectively improving the vibration resistance of the overall structure.

[0058] Furthermore, in this embodiment, the first stacked aluminum wire unit 31 and the second stacked aluminum wire unit 32 have the same structure, both including a plurality of parallel aluminum wires 301. The aluminum wires 301 are divided into several layers and stacked in parallel in sequence, with an equal number of aluminum wires 301 arranged horizontally in each layer. The first stacked aluminum wire unit 31 and the second stacked aluminum wire unit 32 each have two layers of aluminum wires 301, with 13 aluminum wires 301 arranged horizontally in each layer.

[0059] Furthermore, each aluminum wire 301 has an anode region and a cathode region at the same position. The anode regions of each layer of aluminum wire 301 are welded together and the anode region of aluminum wire 301 is bonded together with the common anode region 41.

[0060] Furthermore, such as Figures 5-6 As shown, the aluminum wire 301 is provided with an insulating adhesive layer 3012, which distinguishes the anode and cathode areas of the aluminum wire 301. Specifically, after the upper and middle sections of the aluminum wire 301 are coated with the insulating adhesive layer 3012, the shorter end of the aluminum wire 301 is the anode area, and the longer end is the cathode area. The anode and cathode areas of each aluminum wire 301 are of the same size. Furthermore, except for the portion welded to the common anode area 41, the surface of the anode area of ​​the aluminum wire 301 is coated with an insulating coating 3011. Further, the cathode area of ​​the aluminum wire 301 is provided with a conductive polymer layer 3013, a graphite layer 3014, and a silver paste layer 3015 sequentially from the inside out. Finally, the cathode area of ​​the aluminum wire 301 is adhered to the common cathode area 21 by a silver paste layer 3016.

[0061] Furthermore, the anode area of ​​the stacked aluminum wire structure 3 is also covered with insulating tape 5 to help fix the stacked aluminum wire structure 3 and prevent the anode welding parts from loosening during use.

[0062] This embodiment provides an aluminum wire polymer capacitor, the preparation method of which includes the following steps:

[0063] S1. Preparation of aluminum wire 301: Aluminum ingots with a purity ≥99.7% are heated to a molten state, transforming into liquid aluminum. The liquid aluminum is then injected into a pre-designed mold using a die-casting method. After cooling and solidification, a cylindrical aluminum billet is obtained. The billet is reheated to a suitable temperature and gradually thinned through a stretching process to form a wire-like aluminum wire with a diameter of 1mm to 3mm. The wire-like aluminum wire is cut into aluminum wires 301 with a length of 6.0 to 7.0mm. The prepared aluminum wires 301 are cleaned and chemically etched to create a porous surface. A further chemical treatment is then performed to form a thin aluminum oxide film, increasing the effective area of ​​the aluminum wire and its charge storage capacity, thus resulting in a larger capacity.

[0064] S2. Apply a layer of insulating adhesive evenly at a height of 5.0mm to 5.2mm at one end of the high-purity aluminum wire 301 to form an insulating adhesive layer 3012, distinguishing the long end of the high-purity aluminum wire 301 as the cathode area and the short end as the anode area.

[0065] S3. The cathode region of the high-purity aluminum wire 301 is placed in a conductive polymer material to form a uniform conductive polymer layer 3013 in the cathode region of the aluminum wire 301. The cathode region of the aluminum wire 301 covered with the conductive polymer layer 3013 is then placed in graphite and silver paste in sequence to form a graphite layer 3014 and a silver paste layer 3015 in sequence on the surface of the cathode region.

[0066] S4. Align the anode and cathode areas of the three aluminum wires and arrange them horizontally side by side to form a single layer of aluminum wire 301. Stack two layers of aluminum wire 301 on the front and back sides of the common anode area 41 and the common cathode area 21 in sequence. The cathode areas of each layer of aluminum wire 301 and the common cathode area 21 are bonded to each other with silver paste layer 3016. The anode areas of each layer of aluminum wire 301 and the anode area of ​​aluminum wire 301 and the common anode area 41 are welded and fixed to each other.

[0067] S5. The insulating tape 5 is wound around the outside of the stacked aluminum wire structure 3 on both sides of the common anode region 41 to further fix the stacked aluminum wire structure 3, and the insulating coating 3011 is filled in the gap between the insulating tape 5 and the anode region of the stacked aluminum wire structure 3 to form the capacitor body.

[0068] S6. Finally, the capacitor body is encapsulated in the upper encapsulation shell 1 and the lower encapsulation shell 2 using encapsulation technology. The anode lead 42 and the cathode lead 24 are respectively led out from the lower encapsulation shell 2 from the upper end of the anode conductive plate 4 and the lower end of the cathode conductive plate 2.

[0069] Example 2

[0070] This embodiment proposes an aluminum wire polymer capacitor, which differs from Embodiment 1 only in that when the aluminum wires 301 of each layer of the first stacked aluminum wire unit 31 and the second stacked aluminum wire unit 32 are arranged laterally, a heat dissipation gap is reserved between the aluminum wires 301, and the heat dissipation gap is 0.2mm to 0.4mm.

[0071] To achieve the above structure, the difference between the preparation method of the aluminum wire polymer capacitor in this embodiment and S4-S5 in the preparation method of embodiment 1 is as follows: one aluminum wire 301 from each of the upper and lower layers is taken to form a group. The cathode areas of the aluminum wires 301 in each group are bonded to each other with a silver paste layer 3016, and the anode areas of the aluminum wires 301 in each group are welded and fixed. Each group of aluminum wires 301 is separated by the heat dissipation spacing. The cathode area and the common cathode area 21 of each group of aluminum wires 301 are bonded to each other with a silver paste layer 3016. Insulating tape 5 is used to separate and wind each group of aluminum wires 301 on both sides with uniform tension, starting from the interface area between the insulating tape layer 3012 and the anode area. During winding, a welding area is reserved. Then, the anode area and the common anode area 41 of each group of aluminum wires 301 are welded and fixed to each other. The gap between the insulating tape 5 and the anode area of ​​the aluminum wires 301 is filled with an insulating coating 3011.

[0072] In this step, because reserving a heat dissipation gap may increase the difficulty of welding, a pressing and welding method is used to increase the stability of welding. This ensures that the parallel connection mainly depends on the connection of aluminum wires in the anode and cathode areas. As long as the distance is not too large and the aluminum wires are well fixed, it will not directly affect the parallel connection between the aluminum wires.

[0073] Example 3

[0074] This embodiment proposes an aluminum wire polymer capacitor, which differs from Embodiment 1 only in that the first stacked aluminum wire unit 31 and the second stacked aluminum wire unit 32 on the front and back sides of the common cathode region 21 and the common anode region 41 are each provided with 4 layers of aluminum wire 301, and 2 aluminum wires 301 are arranged side by side in each layer.

[0075] Example 4

[0076] This embodiment proposes an aluminum wire polymer capacitor, which differs from Embodiment 1 only in that the first stacked aluminum wire unit 31 and the second stacked aluminum wire unit 32 on the front and back sides of the common cathode region 21 and the common anode region 41 are each provided with one layer of aluminum wire 301, and four aluminum wires 301 are arranged side by side in each layer.

[0077] Example 5

[0078] This embodiment proposes an aluminum wire polymer capacitor, which differs from Embodiment 1 in that the first stacked aluminum wire unit 31 is only provided on the front side of the common cathode region 21 and the common anode region 41. The first stacked aluminum wire unit 31 has two layers of aluminum wires 301, with 13 aluminum wires 301 arranged side by side in each layer. The fixing foot structure in this embodiment only provides the first fixing foot 22 on the front side of the common cathode region 21, which is used to wrap and fix the first stacked aluminum wire unit 31.

[0079] Example 6

[0080] This embodiment proposes an aluminum wire polymer capacitor, such as Figures 7-8 As shown, the difference from Embodiment 1 is that a first stacked aluminum wire unit 31, a third stacked aluminum wire unit 33 and a fifth stacked aluminum wire unit 35 are provided on the front side of the common cathode region 21 and the common anode region 41, and a second stacked aluminum wire unit 32, a fourth stacked aluminum wire unit 34 and a sixth stacked aluminum wire unit 36 ​​are provided on the back side of the common cathode region 21 and the common anode region 41. Each stacked aluminum wire unit is provided with 2 layers of aluminum wire 301, and 13 aluminum wires 301 are arranged horizontally side by side in each layer.

[0081] The first fixing foot 22 extends from one side of the common cathode region 21 toward the front of the common cathode region 21 and then bends toward the other side of the leading side to wrap and fix the first stacked aluminum wire unit 31, the third stacked aluminum wire unit 33 and the fifth stacked aluminum wire unit 35 that fix the front of the common cathode region 324; the second fixing foot 23 extends from the side corresponding to the leading side of the first fixing foot 22 toward the back of the common cathode region 21 and then bends toward the leading side of the first fixing foot 22 to wrap and fix the second stacked aluminum wire unit 32, the fourth stacked aluminum wire unit 34 and the sixth stacked aluminum wire unit 36 ​​that are on the back of the common cathode region 324.

[0082] With the same material, the capacitance increases primarily with the increase of the total electrode area, i.e., the total area of ​​the aluminum wires. As the size of the stacked aluminum wire units increases, more current paths can be provided, thereby reducing the current density on each path and decreasing resistance. Therefore, the more stacked aluminum wire units there are, the larger the capacitance and the lower the ESR of the capacitor. Compared to a structure where aluminum wires of the same number of layers are arranged as a single stacked aluminum wire unit, the structure in this embodiment, consisting of multiple stacked aluminum wire units, is more stable, and the connection point between the aluminum wires and the common anode region is less likely to break under impact.

[0083] Table 1: Stacked Aluminum Wire Unit Configuration in Examples 1-6

[0084]

[0085] Comparative Example 1

[0086] This comparative example presents an aluminum foil polymer multilayer capacitor, which differs from the aluminum wire polymer capacitor of Example 1 in that conventional aluminum foil is used instead of the single-layer parallel aluminum wire 301 in Example 1.

[0087] The method for preparing the aluminum foil polymer multilayer capacitor provided in this comparative example includes the following steps: integrating four aluminum foils into one unit by connecting the anode and cathode in parallel, setting the length and width of each aluminum foil to be the same as the length and width of the three aluminum wires arranged side by side in each layer in Example 1, and leading conductive leads from the common anode and cathode ends respectively. After assembly, the entire stacked capacitor semi-finished product is transformed into a rectangular capacitor using encapsulation technology.

[0088] Comparative Example 2

[0089] This comparative example proposes an aluminum wire polymer capacitor, which differs from Example 2 only in that when the aluminum wires 301 of each layer of the first stacked aluminum wire unit 31 and the second stacked aluminum wire unit 32 are arranged laterally, a heat dissipation gap of 0.5 mm is reserved between the aluminum wires 301.

[0090] One hundred capacitors from Examples 1-6 and Comparative Examples 1-2 were tested, and the performance test results are shown in Table 2 below:

[0091] Table 2: Performance test results of capacitors prepared by the methods described in Examples 1-6 and Comparative Examples 1-2

[0092] plan Capacity (μF) Initial ESR (mΩ) ESR (mΩ) after reflow soldering Leakage current pass rate (%) Example 1 581.0 3.4 3.9 70％ Example 2 573.6 3.8 4.5 75％ Example 3 614.3 3.5 4.0 68％ Example 4 528.8 4.0 4.2 74％ Example 5 593.3 3.5 3.9 78％ Example 6 866.4 3.2 3.6 70％ Comparative Example 1 420.1 4.7 5.4 65％ Comparative Example 2 568.5 4.6 5.2 69％

[0093] As can be seen from the test data in Table 2, the aluminum wire polymer capacitors prepared by the methods of Examples 1 to 6 have significantly improved capacitance and significantly reduced ESR compared to the multilayer capacitors prepared by the existing method in Comparative Example 1. In Example 2, due to the addition of a heat dissipation gap, the leakage current qualification rate is significantly improved compared to Example 1. In Comparative Example 2, the heat dissipation gap is further increased to 0.5 mm compared to Example 2. Although this can enhance the heat dissipation of the capacitor, the ESR also increases accordingly, and the shock resistance of the entire structure is also reduced.

[0094] Obviously, the embodiments described above are only some embodiments of this application, not all embodiments. The accompanying drawings show preferred embodiments of this application, but do not limit the patent scope of this application. This application can be implemented in many different forms; rather, the purpose of providing these embodiments is to provide a more thorough and comprehensive understanding of the disclosure of this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing specific embodiments, or make equivalent substitutions for some of the technical features. Any equivalent structures made using the content of this application's specification and drawings, directly or indirectly applied to other related technical fields, are similarly within the scope of patent protection of this application.

Claims

1. An aluminum wire polymer capacitor, characterized in that, It includes a housing (1) and a capacitor body; The capacitor body includes a stacked aluminum wire structure (3) and a conductive plate. The conductive plate includes an anode conductive plate (4) and a cathode conductive plate (2). The stacked aluminum wire structure (3) is provided with an anode area and a cathode area. The anode area of ​​the stacked aluminum wire structure (3) is fixedly connected to the anode conductive plate (4), and the cathode area of ​​the stacked aluminum wire structure (3) is fixedly connected to the cathode conductive plate (2). The stacked aluminum wire structure (3) is composed of one or more stacked aluminum wire units; the stacked aluminum wire unit is composed of several parallel aluminum wires (301); The stacked aluminum wire structure (3) is composed of several stacked aluminum wire units, which are located on the front and back sides of the conductive plate and the number of stacked aluminum wire units on the front and back sides of the conductive plate is the same. The stacked aluminum wire unit is composed of one or more layers of parallel aluminum wires (301), with each layer of aluminum wires (301) arranged horizontally; Each of the stacked aluminum wire units has the same number of aluminum wire (301) layers and arrangement.

2. The aluminum wire polymer capacitor according to claim 1, characterized in that, The stacked aluminum wire structure (3) is composed of a first stacked aluminum wire unit (31) and a second stacked aluminum wire unit (32). The first stacked aluminum wire unit (31) and the second stacked aluminum wire unit (32) are located on the front and back sides of the conductive plate, forming a sandwich structure with the conductive plate.

3. The aluminum wire polymer capacitor according to claim 1, characterized in that, When each layer of aluminum wire (301) is arranged horizontally, a heat dissipation gap is reserved between the aluminum wires (301), and the heat dissipation gap is 0.2mm~0.4mm.

4. The aluminum wire polymer capacitor according to claim 1, characterized in that, The aluminum wire (301) has an aluminum purity of ≥99.7% and a diameter of 1mm to 3mm.

5. The aluminum wire polymer capacitor according to claim 1, characterized in that, The conductive plate includes a vertically arranged anode conductive plate (4) and a cathode conductive plate (2). The stacked aluminum wire unit is provided with an anode area and a cathode area. The anode area of ​​the stacked aluminum wire unit is welded to the anode conductive plate (4), and the cathode area of ​​the stacked aluminum wire unit is bonded and fixed to the cathode conductive plate (2).

6. The aluminum wire polymer capacitor according to claim 1, characterized in that, The cathode region of the aluminum wire (301) is provided with a conductive polymer layer (3013), a graphite layer (3014), and a silver paste layer (3015) from the inside to the outside.

7. A method for preparing an aluminum wire polymer capacitor, characterized in that, Includes the following steps: S1. Prepare aluminum wire (301) and apply insulating glue at the same height of each aluminum wire (301) to form an insulating glue layer (3012). Distinguish the long end of the aluminum wire (301) as the cathode area and the short end as the anode area. S2. A conductive polymer layer (3013), a graphite layer (3014), and a silver paste layer (3015) are sequentially formed in the cathode region of the aluminum wire (301). S3. Align the anode and cathode areas of several aluminum wires (301) and arrange them horizontally side by side to form a single layer of aluminum wire (301). Then, stack multiple layers of aluminum wires (301) on the front and back sides of the conductive plate to form a stacked aluminum wire unit. The cathode areas of each layer of aluminum wire (301) and the cathode area and common cathode area (21) of the aluminum wire (301) are bonded to each other through a silver paste layer (3016). The anode areas of each layer of aluminum wire (301) and the anode area and common anode area (41) of the aluminum wire (301) are welded and fixed to each other. S4. Wrap the insulating tape (5) around the outside of the stacked aluminum wire unit on both sides of the common anode region (41), and fill the gap between the insulating tape (5) and the anode region of the stacked aluminum wire unit with an insulating coating (3011) to form the capacitor body. S5. Encapsulate the capacitor body.

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