A moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor and its preparation method

Abstract

The present invention discloses a moisture-resistant and heat-resistant laminated solid-state aluminum electrolytic capacitor and a preparation method thereof, comprising a substrate, a plurality of cores, a ceramic base and a resin shell; the plurality of cores are stacked on the upper surface of the substrate and encapsulated with epoxy resin molding compound, and the semi-finished product after resin encapsulation is aged and screened, and then embedded with the ceramic base with a square open structure; the present invention stacks the plurality of cores on the substrate to achieve a first lead-out, and embeds and bonds the semi-finished product after resin encapsulation with the ceramic base to achieve a second lead-out; wherein, the first-level packaging structure of the resin and the substrate for lead-out retains a certain water vapor channel for the moisture absorption requirement of the capacitor aging process, thereby ensuring the aging effect, and the semi-finished product after resin encapsulation is embedded with the ceramic base to achieve the second lead-out while blocking the original water vapor channel, thereby improving the moisture resistance of the capacitor; in addition, the present invention can also improve the reflow resistance of the capacitor by using a dual substrate structure of a ceramic base and a substrate.

Description

Technical Field

[0001] The present invention relates to the technical field of solid aluminum electrolytic capacitors, in particular to a moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor and a preparation method thereof. Background Art

[0002] Solid-state aluminum electrolytic capacitors include wound-type solid-state aluminum electrolytic capacitors and stacked-type solid-state aluminum electrolytic capacitors. Both use conductive polymers as solid electrolytes. However, stacked-type solid-state aluminum electrolytic capacitors adopt a multi-layer core parallel stacking structure and surface mount design. Compared with wound-type solid-state aluminum electrolytic capacitors, they are more in line with the development needs of the electronic information industry for miniaturization and lightweight whole-machine manufacturing.

[0003] The mature industrial preparation process of stacked solid aluminum electrolytic capacitors is as follows: the cut chemical foil is divided into the anode area and the cathode area with a barrier glue, and a conductive polymer solid electrolyte layer, a conductive carbon paste layer and a conductive silver paste layer are formed in sequence on the surface of the cathode area of ​​the foil to form a capacitor core; multiple capacitor cores are stacked in sequence on an external lead frame to form a capacitor core package, and the anode and cathode are led out. The capacitor core package is resin encapsulated, aged and pinned to obtain a stacked solid aluminum electrolytic capacitor.

[0004] The above-mentioned laminated solid aluminum electrolytic capacitor and its preparation process have the following deficiencies:

[0005] In the traditional lead frame-to-core package lead structure, the gap between the lead frame and the resin encapsulation material forms a short water vapor channel. Water vapor in the environment can easily penetrate the core package, causing the capacitor to absorb moisture and increase losses. When powered on, it generates heat, resulting in increased capacitor leakage current, increased ESR, decreased performance, and shortened lifespan. This limits the application of capacitors in certain harsh environments with high temperature and humidity.

[0006] Organic resin encapsulation shells have poor heat resistance and, due to the limitations of the injection molding process, are prone to developing tiny pores and cracks that are difficult to detect with the naked eye. (Although increasing the injection molding pressure can help reduce the likelihood of pores and cracks in the resin shell, excessive injection pressure can damage the core structure and deform the core, resulting in increased leakage current, decreased capacitance, and even capacitor failure.) During the reflow soldering process for mounting the capacitor on a board, the high welding temperature can exacerbate cracking in the resin shell, subjecting the conductive polymer to high-temperature shock, causing dedoping and decreased conductivity. This can manifest as an increase in the ESR (equivalent series resistance) of the finished capacitor, a decrease in performance, and in severe cases, even capacitor failure. Based on this, the present invention designs a moisture-resistant and heat-resistant laminated solid-state aluminum electrolytic capacitor and a preparation method thereof to address the above-mentioned problems. Summary of the Invention

[0007] The purpose of the present invention is to provide a moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor and a preparation method thereof, so as to solve the problem that the laminated solid aluminum electrolytic capacitor prepared by the prior art has poor high temperature and humidity resistance and welding heat resistance.

[0008] To achieve the above-mentioned object, the present invention provides the following technical solutions: a moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor, comprising a substrate, a plurality of cores, a ceramic base and a resin shell;

[0009] The cross-section of the substrate is rectangular, and a first anode lead-out portion and a first cathode lead-out portion are respectively provided at opposite ends of the substrate. A plurality of cores are stacked in sequence on the upper surface of the substrate, and the anode portion of the core is electrically connected to the first anode lead-out portion, and the cathode portion of the core is electrically connected to the first cathode lead-out portion.

[0010] The ceramic base has a square open structure, and a second anode lead-out portion and a second cathode lead-out portion are provided at both ends of the open bottom of the ceramic base, which cooperate with the first anode lead-out portion and the first cathode lead-out portion, and the second anode lead-out portion and the second cathode lead-out portion extend out of the ceramic base. The substrate is mounted on the open bottom of the ceramic base, and the first anode lead-out portion is electrically conductive with the second anode lead-out portion, and the first cathode lead-out portion is electrically conductive with the second cathode lead-out portion.

[0011] The resin shell is tightly embedded in the square opening of the ceramic base, and covers the upper surface, surrounding sides and a plurality of chip cores of the substrate.

[0012] Preferably, the length of the substrate is 100% to 120% of the length of the core, and the width of the substrate is 100% to 120% of the width of the core.

[0013] Preferably, the height of the ceramic base is 50%-100% of the total height of the capacitor, the length of the open interior of the ceramic base is not less than 110% of the length of the substrate, and the width of the open interior of the ceramic base is not less than 110% of the width of the substrate.

[0014] Preferably, the first anode lead-out portion includes a first anode horizontal portion, a first anode connecting portion, and a first anode pin. The cross-sectional shapes of the first anode horizontal portion and the first anode pin are both rectangular, and the first anode horizontal portion and the first anode pin are respectively arranged parallel to the upper and lower surfaces of the substrate. The first anode horizontal portion and the first anode pin are connected and electrically conductive via the first anode connecting portion, and the first anode connecting portion is arranged inside the substrate.

[0015] The structure and shape of the first cathode lead-out portion are consistent with those of the first anode lead-out portion.

[0016] Preferably, the distance between the edges of the first anode pin and the first cathode pin, where the edges are close to each other, is 50% to 70% of the length of the substrate.

[0017] Preferably, the second anode lead-out portion includes a second anode horizontal portion, a second anode connecting portion, and a second anode pin, the second anode pin includes a second anode pin horizontal portion and a second anode pin vertical portion vertically connected to each other, and the cross-sectional shape of the second anode horizontal portion, the second anode pin horizontal portion, and the second anode pin vertical portion is rectangular, the second anode horizontal portion and the second anode pin horizontal portion are respectively arranged parallel to the groove bottom surface and the bottom surface of the ceramic base, the second anode horizontal portion and the second anode pin horizontal portion are connected and electrically conductive via the second anode connecting portion, and the second anode connecting portion passes through the interior of the ceramic base, the second anode pin vertical portion is arranged on the outer surface of the end of the ceramic base, and the first anode pin is electrically conductive to the second anode horizontal portion;

[0018] The structure and shape of the second cathode lead-out portion are consistent with those of the second anode lead-out portion, and the first cathode lead is electrically connected to the second cathode horizontal portion.

[0019] Preferably, the distance between the edges of the second anode horizontal portion and the second cathode horizontal portion close to each other is 50% to 70% of the length of the ceramic base, and the distance between the edges of the second anode pin horizontal portion and the second cathode pin horizontal portion close to each other is 50% to 70% of the length of the capacitor.

[0020] Preferably, outer surfaces of the second anode pin horizontal portion, the second anode pin vertical portion, the second cathode pin horizontal portion and the second cathode pin vertical portion away from the ceramic base are all provided with a tin layer.

[0021] A method for preparing a moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor, the method comprising the following steps:

[0022] S1. Stacking a plurality of cores in sequence on a substrate of an external device, with the anode portion and cathode portion of the core respectively attached to the first anode horizontal portion and the first cathode horizontal portion and electrically connected to form a core package;

[0023] S2. Encapsulating the core package with epoxy resin molding compound, forming a resin shell on the outside of the core package to obtain a semi-finished capacitor, wherein the lower surface of the substrate, the first anode pin, and the first cathode pin are exposed outside the resin shell;

[0024] S3. Performing moisture absorption, aging and electrical performance testing on the prepared capacitor semi-finished products to screen out capacitor semi-finished products with qualified electrical performance;

[0025] S4. Connecting the screened semi-finished capacitors with qualified electrical properties to an external ceramic base to produce moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitors.

[0026] Preferably, the step S4 is specifically as follows:

[0027] S41. On the inner surface of the square open structure of the ceramic base, except for the second anode horizontal portion and the second cathode horizontal portion, the surfaces of the remaining areas are coated with an insulating adhesive.

[0028] S42. Embed the semi-finished capacitor with qualified electrical performance into the ceramic base, so that the first anode pin and the second anode horizontal portion and the first cathode pin and the second cathode horizontal portion are bonded.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The present invention stacks several capacitor cores on a substrate to achieve the first lead-out, and engages and bonds the resin-encapsulated semi-finished product with a ceramic base to achieve the second lead-out; wherein, the first-level packaging structure of the resin and the substrate lead-out retains a certain water vapor channel for the moisture absorption requirement of the capacitor aging process, thereby ensuring the aging effect. After aging and electrical performance screening, the capacitor is wrapped with a ceramic base on the bottom and sides. On the basis of forming a client application welding terminal, the excellent temperature resistance of the ceramic material can be utilized, and a double substrate can be formed in combination with an FR-4 substrate with a small thermal conductivity coefficient and good thermal insulation performance, thereby effectively reducing the damage of the core caused by high-temperature impact and improving the welding heat resistance of the capacitor during the upper board welding process; after the capacitor semi-finished product is connected to the ceramic base, the original water vapor channel is sealed by insulating glue, thereby improving the moisture resistance of the finished capacitor during client application after leaving the factory. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0032] Figure 1 Schematic diagram of the structure of the solid aluminum electrolytic capacitor of the present invention;

[0033] Figure 2 Schematic diagram of the front cross-section structure of the solid aluminum electrolytic capacitor of the present invention;

[0034] Figure 3 Schematic diagram of the structure of the substrate in the solid aluminum electrolytic capacitor of the present invention;

[0035] Figure 4Schematic diagram of the bottom structure of the substrate in the solid aluminum electrolytic capacitor of the present invention;

[0036] Figure 5 Schematic diagram of the structure of the ceramic base in the solid aluminum electrolytic capacitor of the present invention;

[0037] Figure 6 Schematic diagram of the top view of the ceramic base in the solid aluminum electrolytic capacitor of the present invention;

[0038] Figure 7 Schematic diagram of the bottom view of the ceramic base in the solid aluminum electrolytic capacitor of the present invention;

[0039] Figure 8 Schematic diagram of the structure of the first anode lead-out portion of the solid-state aluminum electrolytic capacitor of the present invention;

[0040] Figure 9 Schematic diagram of the structure of the second anode lead-out portion of the solid aluminum electrolytic capacitor of the present invention;

[0041] Figure 10 The figure is a schematic flow chart of the preparation method of the solid aluminum electrolytic capacitor of the present invention.

[0042] In the accompanying drawings, the components represented by the reference numerals are as follows:

[0043] Substrate; 2. Core; 3. Ceramic base; 4. Resin shell; 5. First anode lead-out portion; 51. First anode horizontal portion; 52. First anode connecting portion; 53. First anode pin; 6. First cathode lead-out portion; 7. Second anode lead-out portion; 71. Second anode horizontal portion; 72. Second anode connecting portion; 73. Second anode pin horizontal portion; 74. Second anode pin vertical portion; 8. Second cathode lead-out portion. Implementation Method

[0044] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0045] See also Figure 1-9 As shown, a technical solution provided by the present invention is:

[0046] A moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor, comprising a substrate 1, a plurality of cores 2, a ceramic base 3 and a resin shell 4;

[0047] The cross-section of the substrate 1 is rectangular. A first anode lead-out portion 5 and a first cathode lead-out portion 6 are provided at opposite ends of the substrate 1. A plurality of cores 2 are stacked in sequence on the upper surface of the substrate 1. The anode portion of the core 2 is electrically connected to the first anode lead-out portion 5, and the cathode portion of the core 2 is electrically connected to the first cathode lead-out portion 6.

[0048] The ceramic base 3 has a square open structure. A second anode lead-out portion 7 and a second cathode lead-out portion 8 are provided at both ends of the open bottom of the ceramic base 3, which cooperate with the first anode lead-out portion 5 and the first cathode lead-out portion 6. The second anode lead-out portion 7 and the second cathode lead-out portion 8 extend out of the ceramic base 3. The substrate 1 is mounted on the open bottom of the ceramic base 3. The first anode lead-out portion 5 is electrically conductive with the second anode lead-out portion 7, and the first cathode lead-out portion 6 is electrically conductive with the second cathode lead-out portion 8.

[0049] The resin shell 4 is tightly fitted in the square opening of the ceramic base 3 , and covers the upper surface, surrounding sides and a plurality of chip cores 2 of the substrate 1 .

[0050] Specifically, the length of the substrate 1 is 100% to 120% of the length of the core 2 , and the width of the substrate 1 is 100% to 120% of the width of the core 2 .

[0051] It can be seen from the above description that the limitation on the length and width of the substrate is to achieve the supporting function of the substrate for the core.

[0052] Specifically, the height of the ceramic base 3 is 50%-100% of the total height of the capacitor, the length of the open interior of the ceramic base 3 is not less than 110% of the length of the substrate 1, and the width of the open interior of the ceramic base 3 is not less than 110% of the width of the substrate 1.

[0053] As can be seen from the above description, the limitation on the length, width and height of the ceramic base is to reserve space for the thickness of the resin shell so as to achieve a tight fit between the ceramic base and the resin shell.

[0054] Specifically, the first anode lead-out portion 5 includes a first anode horizontal portion 51, a first anode connecting portion 52, and a first anode pin 53. The cross-sectional shapes of the first anode horizontal portion 51 and the first anode pin 53 are both rectangular, and the first anode horizontal portion 51 and the first anode pin 53 are respectively arranged parallel to the upper and lower surfaces of the substrate 1. The first anode horizontal portion 51 and the first anode pin 53 are connected and electrically conductive via the first anode connecting portion 52, and the first anode connecting portion 52 is arranged inside the substrate 1.

[0055] The structure and shape of the first cathode lead-out portion 6 are consistent with those of the first anode lead-out portion 5 .

[0056] Specifically, the distance between the edges of the first anode pin 53 and the first cathode pin, which are close to each other, is 50% to 70% of the length of the substrate 1 (e.g. Figure 4 L1 in the figure).

[0057] Specifically, the second anode lead-out portion 7 includes a second anode horizontal portion 71, a second anode connecting portion 72, and a second anode pin. The second anode pin includes a second anode pin horizontal portion 73 and a second anode pin vertical portion 74 that are perpendicularly connected to each other. The cross-sectional shape of the second anode horizontal portion 71, the second anode pin horizontal portion 73, and the second anode pin vertical portion 74 is rectangular. The second anode horizontal portion 71 and the second anode pin horizontal portion 73 are respectively arranged parallel to the groove bottom surface and the bottom surface of the ceramic base 3. The second anode horizontal portion 71 and the second anode pin horizontal portion 73 are connected and electrically conductive through the second anode connecting portion 72. The second anode connecting portion 72 is arranged inside the ceramic base 3. The second anode pin vertical portion 74 is arranged on the outer surface of the end of the ceramic base 3. The first anode pin 53 is electrically conductive to the second anode horizontal portion 71.

[0058] The structure and shape of the second cathode lead-out portion 8 are consistent with those of the second anode lead-out portion 7 , and the first cathode lead is electrically connected to the second cathode horizontal portion.

[0059] Specifically, the distance between the edges of the second anode horizontal portion 71 and the second cathode horizontal portion close to each other is 50% to 70% of the length of the ceramic base 3 (e.g. Figure 6 As shown in L2 in FIG), the distance between the edges of the second anode pin horizontal portion 73 and the second cathode pin horizontal portion close to each other is 50% to 70% of the capacitor length (as shown in FIG). Figure 7 L3 in Figure 1).

[0060] From the above description, it can be seen that the limitation on the edge spacing between the first anode pin and the first cathode pin, and the edge spacing between the second anode horizontal portion and the second cathode horizontal portion is to avoid electrical conduction between the anode and cathode due to diffusion contact of the conductive adhesive during the bonding process of the ceramic base and the resin shell, resulting in a short circuit in the finished capacitor; the limitation on the edge spacing between the second anode horizontal portion and the second cathode horizontal portion is to avoid electrical conduction between the anode and cathode of the capacitor due to diffusion contact of the solder paste during the client's upper board welding, resulting in abnormality in the client's product.

[0061] Specifically, outer surfaces of the second anode pin horizontal portion 73 , the second anode pin vertical portion 74 , the second cathode pin horizontal portion, and the second cathode pin vertical portion away from the ceramic base 3 are all provided with a tin layer.

[0062] See also Figure 10 As shown, another technical solution provided by the present invention is:

[0063] A method for preparing a moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor, the method comprising the following steps:

[0064] S1. Stacking a plurality of cores 2 sequentially on an external substrate 1, with the anode portion and cathode portion of the core 2 respectively attached to the first anode horizontal portion 51 and the first cathode horizontal portion and electrically connected to form a core package;

[0065] S2. Encapsulating the core package with epoxy resin molding compound, forming a resin shell 4 on the outside of the core package, and manufacturing a semi-finished capacitor, wherein the lower surface of the substrate 1, the first anode pin 53, and the first cathode pin are exposed outside the resin shell 4;

[0066] S3. Performing moisture absorption, aging and electrical performance testing on the prepared capacitor semi-finished products to screen out capacitor semi-finished products with qualified electrical performance;

[0067] S4. Connect the screened semi-finished capacitors with qualified electrical properties to the external ceramic base 3 to produce moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitors.

[0068] Specifically, step S4 is as follows:

[0069] S41, coating the inner surface of the square open structure of the ceramic base 3 with an insulating adhesive except for the second anode horizontal portion 71 and the second cathode horizontal portion;

[0070] S42 , embedding a semi-finished capacitor with qualified electrical performance into the ceramic base 3 , so that the first anode pin 53 and the second anode horizontal portion 71 and the first cathode pin and the second cathode horizontal portion are bonded together.

[0071] Embodiment 1 of the present invention is ( Figure 1-7 shown):

[0072] A moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor, comprising a substrate 1 (made of FR-4 epoxy glass cloth laminate), a plurality of cores 2, a ceramic base 3 (made of alumina ceramic) and a resin shell 4;

[0073] The cross-section of the substrate 1 is rectangular. A first anode lead-out portion 5 and a first cathode lead-out portion 6 are provided at opposite ends of the substrate 1. A plurality of cores 2 are stacked in sequence on the upper surface of the substrate 1. The anode portion of the core 2 is electrically connected to the first anode lead-out portion 5, and the cathode portion of the core 2 is electrically connected to the first cathode lead-out portion 6.

[0074] In this embodiment, the length of the substrate 1 is 100% to 120% (preferably 110%) of the length of the core 2 , and the width of the substrate 1 is 100% to 120% (preferably 110%) of the width of the core 2 ;

[0075] In this embodiment, the first anode lead-out portion 5 includes a first anode horizontal portion 51, a first anode connecting portion 52, and a first anode pin 53. The cross-sectional shapes of the first anode horizontal portion 51 and the first anode pin 53 are both rectangular, and the first anode horizontal portion 51 and the first anode pin 53 are respectively arranged parallel to the upper and lower surfaces of the substrate 1. The first anode horizontal portion 51 and the first anode pin 53 are connected and electrically conductive via the first anode connecting portion 52, and the first anode connecting portion 52 is arranged inside the substrate 1.

[0076] The structure and shape of the first cathode lead-out portion 6 are consistent with those of the first anode lead-out portion 5 , and the distance between the edges of the first anode pin 53 and the first cathode pin where they are close to each other is 50% to 70% (preferably 60%) of the length of the substrate 1 ;

[0077] In this embodiment, the first anode lead-out portion 5 and the first cathode lead-out portion 6 are made of copper and copper alloy;

[0078] The ceramic base 3 has a square open structure. A second anode lead-out portion 7 and a second cathode lead-out portion 8 are provided at both ends of the open bottom of the ceramic base 3, which cooperate with the first anode lead-out portion 5 and the first cathode lead-out portion 6. The second anode lead-out portion 7 and the second cathode lead-out portion 8 extend out of the ceramic base 3. The substrate 1 is mounted on the open bottom of the ceramic base 3. The first anode lead-out portion 5 is electrically conductive with the second anode lead-out portion 7, and the first cathode lead-out portion 6 is electrically conductive with the second cathode lead-out portion 8.

[0079] In this embodiment, the height of the ceramic base 3 is 50%-100% (preferably 75%) of the total height of the capacitor, the length of the open interior of the ceramic base 3 is not less than 110% (preferably 120%) of the length of the substrate 1, and the width of the open interior of the ceramic base 3 is not less than 110% (preferably 120%) of the width of the substrate 1.

[0080] In this embodiment, the second anode lead-out portion 7 includes a second anode horizontal portion 71, a second anode connecting portion 72, and a second anode pin. The second anode pin includes a second anode pin horizontal portion 73 and a second anode pin vertical portion 74 that are perpendicularly connected to each other. The cross-sectional shape of the second anode horizontal portion 71, the second anode pin horizontal portion 73, and the second anode pin vertical portion 74 is rectangular. The second anode horizontal portion 71 and the second anode pin horizontal portion 73 are respectively arranged parallel to the groove bottom surface and the bottom surface of the ceramic base 3. The second anode horizontal portion 71 and the second anode pin horizontal portion 73 are connected and electrically conductive via the second anode connecting portion 72. The second anode connecting portion 72 is arranged inside the ceramic base 3. The second anode pin vertical portion 74 is arranged on the outer surface of the end of the ceramic base 3. The first anode pin 53 is electrically conductive to the second anode horizontal portion 71.

[0081] The structure and shape of the second cathode lead-out portion 8 are consistent with those of the second anode lead-out portion 7, and there is electrical conduction between the first cathode pin and the second cathode horizontal portion, and the outer surfaces of the second anode pin horizontal portion 73, the second anode pin vertical portion 74, the second cathode pin horizontal portion, and the second cathode pin vertical portion away from the ceramic base 3 are all provided with a tin layer;

[0082] In this embodiment, the distance between the edges of the second anode horizontal portion 71 and the second cathode horizontal portion is 50% to 70% (preferably 60%) of the length of the ceramic base 3, and the distance between the edges of the second anode pin horizontal portion 73 and the second cathode pin horizontal portion is 50% to 70% (preferably 60%) of the capacitor length.

[0083] In this embodiment, the second anode lead-out portion 7 and the second cathode lead-out portion 8 are made of copper and copper alloy;

[0084] The resin shell 4 is tightly fitted in the square opening of the ceramic base 3 , and covers the upper surface, surrounding sides and a plurality of chip cores 2 of the substrate 1 .

[0085] The specific preparation method of the above-mentioned moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor is as follows:

[0086] S1. Stacking a plurality of cores 2 sequentially on an external substrate 1, with the anode portion and cathode portion of the core 2 respectively attached to the first anode horizontal portion 51 and the first cathode horizontal portion and electrically connected to form a core package;

[0087] In this embodiment, the preparation method of the core 2 is as follows: cutting the formed aluminum foil into rectangles to form a first aluminum foil; coating the first aluminum foil with a barrier adhesive to prepare an insulating barrier tape, dividing the anode region and the cathode region to obtain a second aluminum foil; performing a re-formation repair treatment on the dielectric layer on the cathode region side of the second aluminum foil to obtain a third aluminum foil; forming a conductive polymer layer on the cathode region surface of the third aluminum foil to obtain a fourth aluminum foil; impregnating the cathode region of the fourth aluminum foil with a conductive graphite emulsion and then drying it to form a conductive carbon paste layer to obtain a fifth aluminum foil; impregnating the cathode region of the fifth aluminum foil with a conductive silver paste and then drying it to form a conductive silver paste layer to obtain the core 2;

[0088] In this embodiment, the specific stacking method between each core 2 is as follows: the anode portion of the first core 2 and the first anode horizontal portion 51, as well as the anode portions of several cores 2, are connected and electrically conductive by welding; the cathode portion of the first core 2 and the first cathode horizontal portion, as well as the cathode portions of several cores 2, are bonded and electrically conductive by conductive silver glue;

[0089] S2. Encapsulating the core package with epoxy resin molding compound, forming a resin shell 4 on the outside of the core package, and manufacturing a semi-finished capacitor, wherein the lower surface of the substrate 1, the first anode pin 53, and the first cathode pin are exposed outside the resin shell 4 (i.e., the lower surface of the substrate 1, the first anode pin 53, and the first cathode pin are not covered);

[0090] S3. Performing moisture absorption, aging and electrical performance testing on the prepared capacitor semi-finished products to screen out capacitor semi-finished products with qualified electrical performance;

[0091] S4, connecting the screened semi-finished capacitor with qualified electrical performance to the external ceramic base 3 to produce a moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor;

[0092] In this embodiment, the specific connection method between the semi-finished capacitor and the ceramic base 3 is:

[0093] S41, coating the inner surface of the square open structure of the ceramic base 3 with an insulating adhesive except for the second anode horizontal portion 71 and the second cathode horizontal portion;

[0094] S42. Embed the semi-finished capacitor with qualified electrical performance into the ceramic base 3, and bond the first anode pin 53 to the second anode horizontal portion 71 and the first cathode pin to the second cathode horizontal portion to obtain a moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor.

[0095] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes may be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor, characterized by: It comprises a substrate (1), a plurality of chip cores (2), a ceramic base (3) and a resin shell (4); The cross-sectional shape of the substrate (1) is rectangular, and a first anode lead-out portion (5) and a first cathode lead-out portion (6) are respectively provided at opposite ends of the substrate (1), and a plurality of cores (2) are stacked in sequence on the upper surface of the substrate (1), and the anode portion of the core (2) is electrically connected to the first anode lead-out portion (5), and the cathode portion of the core (2) is electrically connected to the first cathode lead-out portion (6); The ceramic base (3) is a square open structure, and the two ends of the open bottom of the ceramic base (3) are provided with a second anode lead-out portion (7) and a second cathode lead-out portion (8) that cooperate with the first anode lead-out portion (5) and the first cathode lead-out portion (6), and the second anode lead-out portion (7) and the second cathode lead-out portion (8) pass through the outside of the ceramic base (3), and the substrate (1) is mounted on the open bottom of the ceramic base (3), and the first anode lead-out portion (5) and the second anode lead-out portion (7) are electrically conductive, and the first cathode lead-out portion (6) and the second cathode lead-out portion (8) are electrically conductive; The resin shell (4) is tightly fitted into the square opening of the ceramic base (3), and the resin shell (4) covers the upper surface, surrounding sides and a plurality of cores (2) of the substrate (1).

2. The moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor according to claim 1, characterized in that: The length of the substrate (1) is 100% to 120% of the length of the core (2), and the width of the substrate (1) is 100% to 120% of the width of the core (2).

3. The moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor according to claim 1, characterized in that: The height of the ceramic base (3) is 50%-100% of the total height of the capacitor, the length of the open interior of the ceramic base (3) is not less than 110% of the length of the substrate (1), and the width of the open interior of the ceramic base (3) is not less than 110% of the width of the substrate (1).

4. The moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor according to claim 1, characterized in that: The first anode lead-out portion (5) comprises a first anode horizontal portion (51), a first anode connecting portion (52) and a first anode pin (53); the cross-sectional shapes of the first anode horizontal portion (51) and the first anode pin (53) are both rectangular, and the first anode horizontal portion (51) and the first anode pin (53) are respectively arranged in parallel on the upper and lower surfaces of the substrate (1); the first anode horizontal portion (51) and the first anode pin (53) are connected and electrically conductive via the first anode connecting portion (52), and the first anode connecting portion (52) is arranged inside the substrate (1); The structure and shape of the first cathode lead-out portion (6) are consistent with those of the first anode lead-out portion (5).

5. The moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor according to claim 4, characterized in that: The distance between the edges of the first anode pin (53) and the first cathode pin, where the edges are close to each other, is 50% to 70% of the length of the substrate (1).

6. The moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor according to claim 4, characterized in that: The second anode lead-out portion (7) includes a second anode horizontal portion (71), a second anode connecting portion (72) and a second anode pin, the second anode pin includes a second anode pin horizontal portion (73) and a second anode pin vertical portion (74) vertically connected to each other, and the cross-sectional shape of the second anode horizontal portion (71), the second anode pin horizontal portion (73) and the second anode pin vertical portion (74) is rectangular, the second anode horizontal portion (71) and the second anode pin horizontal portion (73) are respectively arranged in parallel on the groove bottom surface and the bottom surface of the ceramic base (3), the second anode horizontal portion (71) and the second anode pin horizontal portion (73) are connected and electrically conductive through the second anode connecting portion (72), and the second anode connecting portion (72) is passed through the inside of the ceramic base (3), the second anode pin vertical portion (74) is arranged on the outer surface of the end of the ceramic base (3), and the first anode pin (53) is electrically conductive with the second anode horizontal portion (71); The structure and shape of the second cathode lead-out portion (8) are consistent with those of the second anode lead-out portion (7), and the first cathode lead and the second cathode horizontal portion are electrically conductive.

7. The moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor according to claim 6, characterized in that: The distance between the edges of the second anode horizontal portion (71) and the second cathode horizontal portion, which are close to each other, is 50% to 70% of the length of the ceramic base (3); and the distance between the edges of the second anode pin horizontal portion (73) and the second cathode pin horizontal portion, which are close to each other, is 50% to 70% of the length of the capacitor.

8. The moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor according to claim 7, characterized in that: The outer surfaces of the second anode pin horizontal portion (73), the second anode pin vertical portion (74), the second cathode pin horizontal portion, and the second cathode pin vertical portion away from the ceramic base (3) are all provided with a tin layer.

9. A method for preparing the moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor according to any one of claims 1 to 8, characterized in that: The preparation method comprises the following steps: S1, stacking a plurality of cores (2) in sequence on an external substrate (1), and placing the anode portion and cathode portion of the core (2) in contact with the first anode horizontal portion (51) and the first cathode horizontal portion, respectively, and electrically conducting the contact, to obtain a core package; S2, encapsulating the core package with epoxy resin molding compound, forming a resin shell (4) outside the core package, and obtaining a capacitor semi-finished product, wherein the lower surface of the substrate (1), the first anode pin (53), and the first cathode pin are exposed outside the resin shell (4); S3. Performing moisture absorption, aging and electrical performance testing on the prepared capacitor semi-finished products to screen out capacitor semi-finished products with qualified electrical performance; S4. Connecting the screened capacitor semi-finished product with qualified electrical performance to an external ceramic base (3) to obtain a moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor.

10. The method for preparing a moisture-resistant and heat-resistant laminated solid aluminum electrolytic capacitor according to claim 9, characterized in that: The step S4 is specifically as follows: S41, coating the inner surface of the square open structure of the ceramic base (3) with an insulating adhesive except for the second anode horizontal portion (71) and the second cathode horizontal portion; S42, embedding a semi-finished capacitor with qualified electrical performance into a ceramic base (3), so that the first anode pin (53) and the second anode horizontal portion (71) are bonded together, and the first cathode pin and the second cathode horizontal portion are bonded together.

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