Capacitor jelly roll, and dual-substrate laminated solid aluminum electrolytic capacitor and manufacturing method therefor

Abstract

The present invention relates to the technical field of solid aluminum electrolytic capacitors, and in particular to a capacitor jelly roll, and a dual-substrate laminated solid aluminum electrolytic capacitor and a manufacturing method therefor. The capacitor jelly roll comprises N cores, N+1 concentric-square-shaped thin plates, and two substrates. The N+1 concentric-square-shaped thin plates and the N cores are sequentially and alternately laminated to form a jelly roll semi-finished product. Moreover, anode parts of every two adjacent cores are electrically connected, and cathode parts of every two adjacent cores are electrically connected. When the concentric-square-shaped thin plates and the cores are laminated, the space of the concentric-square-shaped thin plates that is not in contact with the cores is filled with an insulating glue. The concentric-square-shaped thin plates and the cores are alternately laminated to form the jelly roll; the peripheral size of each concentric-square-shaped thin plate is set to be larger than that of each core; after the concentric-square-shaped thin plates and the cores are laminated, the space of the concentric-square-shaped thin plates not occupied by the cores is bonded and sealed by the insulating glue, so that the cores are supported and protected and delamination is prevented, and electrical performance degradation caused by penetration of resin from layers of the cores during resin packaging of the jelly roll can be prevented.

Description

Capacitor core package, double-substrate laminated solid aluminum electrolytic capacitor and preparation method thereof Technical Field

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

[0002] The rapid development of the electronics and information technology industry has driven a booming semiconductor industry. Solid-state aluminum electrolytic capacitors, as key passive electronic components, have broad application prospects. Multilayer solid-state aluminum electrolytic capacitors, with their conductive polymer as the solid electrolyte and a multi-layer, parallel-stacked structure and surface-mount design, offer advantages such as small size, long life, and high environmental and safety characteristics. These capacitors are well-suited to the electronics and information technology industry's growing demand for smaller, thinner, and more efficient devices.

[0003] The mature industrial preparation process of laminated solid-state aluminum electrolytic capacitors is as follows: the cut chemical foil is divided into the anode area and the cathode area with 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 the planar lead frame of the peripheral device to form a capacitor core package, and the anode and cathode are led out. The capacitor core package is resin encapsulated, aged and the pins are bent to form a laminated solid-state aluminum electrolytic capacitor.

[0004] However, the core package prepared by the above process has the following problems:

[0005] In the prior art, after the core is laid on the top and bottom surfaces of a planar leadframe, a gap exists between the leadframe's anode and cathode tongues. During the packaging process, resin encapsulation easily squeezes in through this gap, causing compression deformation of the core, increasing leakage current and ESR. In severe cases, it can cause delamination, resulting in insufficient capacity and capacitor failure. The cathode regions of the core are bonded only with conductive silver glue, allowing resin encapsulation to easily intrude between the layers of the core cathode region, causing increased leakage current and ESR. Based on this, the present invention designs a capacitor core package, a dual-substrate laminated solid-state aluminum electrolytic capacitor, and a method for preparing the same to address the aforementioned issues.

[0006] Summary of the Invention

[0007] The object of the present invention is to provide a capacitor core package, a double-substrate laminated solid aluminum electrolytic capacitor and a preparation method thereof, so as to solve the problem that a gap exists between the anode tongue and the cathode tongue of the existing capacitor core package, and the cathode areas of the core are only bonded by conductive silver glue. During the packaging process, the resin packaging material easily invades the above-mentioned weak points, causing leakage current, increased ESR, and even capacitor failure.

[0008] To achieve the above object, the present invention provides a first technical solution:

[0009] A capacitor core package comprises N cores, N+1 U-shaped thin plates, and two base plates, wherein the cross-sectional area of ​​the U-shaped thin plates is larger than the cross-sectional area of ​​the cores, wherein the N+1 U-shaped thin plates and the N cores are alternately stacked in sequence to form a core package semi-finished product, wherein the anode portions of two adjacent cores are electrically connected, and the cathode portions of two adjacent cores are electrically connected, and when the U-shaped thin plates and the cores are stacked, the space between the U-shaped thin plates and the cores that is not in contact is filled with insulating glue;

[0010] Two lead-out parts are symmetrically provided at opposite ends of the substrate. The two substrates are respectively adhered to opposite sides of the core package semi-finished product, and the lead-out parts at both ends of the substrate are respectively electrically connected to the anode and cathode parts of the core.

[0011] Preferably, the opposite ends of the U-shaped thin plate are respectively an anode plate and a cathode plate, and the anode plate and the cathode plate are connected by two side plates. The anode plate and the anode portion of the core are both penetrated by a through hole. When the U-shaped thin plate and the core are stacked, the through holes are aligned with each other and connected, and the through holes are filled with conductive silver paste.

[0012] A U-shaped copper foil is inserted on the outside of the cathode plate, and the opening of the U-shaped copper foil is set away from the anode plate. When the U-shaped thin plate and the core are stacked, the upper and lower sides of the U-shaped copper foil are respectively in contact with the cathode part of the adjacent core and are electrically connected.

[0013] Preferably, one end of the anode plate close to the cathode plate is flush with one end of the core barrier glue close to the cathode part, the length of the anode plate is 100%-120% of the sum of the lengths of the anode part of the core and the barrier glue, and the width of the anode plate is 120%-150% of the width of the core;

[0014] The length of the cathode portion of each core sandwiched between the cathode plates of the two adjacent U-shaped thin plates is 20%-50% of the length of the cathode portion; the width of the cathode plates is 60%-80% of the width of the core;

[0015] The sum of the length of the hollowed-out portion in the middle of the U-shaped thin plate and the length of the cathode plate is 110%-120% of the length of the cathode portion of the core, and the width of the U-shaped thin plate is 120%-150% of the width of the core.

[0016] Preferably, the lead-out portion includes a tongue, a connecting portion and a pin, the tongue and the pin are arranged in parallel on two opposite surfaces of the substrate, and the tongue is electrically connected to the core package semi-finished product, the connecting portion is passed through the inside of the substrate, and the opposite ends of the connecting portion are respectively vertically connected to the tongue and the pin and are electrically conductive.

[0017] Preferably, a rectangular protrusion is provided on a side of the substrate away from the core package semi-finished product, the length and width of the rectangular protrusion are 80%-90% of the length and width of the substrate respectively, and the height of the rectangular protrusion is 0.3mm-0.5mm. The tongue is provided on a side of the substrate where no rectangular protrusion is provided, and one end of the tongue is flush with one end of the substrate, and the pin is horizontally provided on the surface of the rectangular protrusion, and one end of the pin is flush with one end of the rectangular protrusion.

[0018] Preferably, the distance between the edges of the two tongues on the same substrate is 40%-70% of the length of the substrate, and the distance between the edges of the two pins on the same substrate is 40%-60% of the length of the rectangular protrusion of the substrate.

[0019] A double-substrate laminated solid aluminum electrolytic capacitor includes a resin shell, a waterproof coating, and a capacitor core package. The waterproof coating is applied to the four side surfaces of the capacitor core package. The resin shell wraps around the waterproof coating and the portion of the substrate in the capacitor core package excluding the rectangular raised portion. The four sides of the rectangular raised portion of the substrate are wrapped inside the resin shell, and the surface of the rectangular raised portion of the substrate with pins is exposed from the resin shell.

[0020] A method for preparing a double-substrate laminated solid aluminum electrolytic capacitor, the method comprising the following steps:

[0021] S1: Alternately stacking N+1 U-shaped sheets and N cores from bottom to top according to the designed number of layers, and electrically connecting the U-shaped copper foil on the U-shaped sheets to the cathodes of the two adjacent cores to form the first core package semi-finished product;

[0022] S2: Drilling a through hole at one end of the first core package semi-finished product near the core anode portion continuously penetrating the anode plates of N+1 U-shaped thin plates and the anode portions of N cores, and filling the through hole with conductive silver paste to ensure electrical conduction between the anode portions of the N cores, thereby obtaining a core package semi-finished product;

[0023] S3: Bonding the upper and lower surfaces of the semi-finished core package to an external substrate to obtain a capacitor core package;

[0024] S4: Coating waterproof material on the four sides of the capacitor core package to form a waterproof coating;

[0025] S5: The sides of the capacitor core package and the edges of the substrate are encapsulated with epoxy resin to form a resin shell, thereby obtaining a double-substrate laminated solid aluminum electrolytic capacitor.

[0026] Preferably, the stacking method of the core and the U-shaped thin plate in step S1 is specifically as follows:

[0027] S11, coating insulating glue on one side of the anode plate of the first U-shaped thin plate, and coating conductive silver glue on the U-shaped copper foil of the cathode plate on the same side;

[0028] S12. Adhere the lower surface of the first core to the first U-shaped sheet, so that the anode portion of the core and the barrier adhesive are bonded to the anode plate of the first U-shaped sheet, and the end of the anode plate close to the cathode plate is flush with the end of the barrier adhesive close to the cathode portion. At the same time, adhere the cathode portion of the core to the U-shaped copper foil on the cathode plate of the first U-shaped sheet and electrically conduct thereto. Then, apply insulating adhesive to the areas of the two side plates of the first U-shaped sheet that are not covered by the first core.

[0029] S13. Apply insulating glue and conductive silver glue respectively on one side of the second U-shaped thin plate according to the method of S11. Then, adhere the glue-coated side of the second U-shaped thin plate to the upper surface of the first core according to the method of S12. The width of the area where the two ends of the cathode portion of the first core are sandwiched by the two side plates of the upper and lower adjacent U-shaped thin plates are equal. The stacking of the first core is completed.

[0030] S14. Following the method of S11, apply insulating glue and conductive silver glue to the other side of the second U-shaped sheet. Following the method of S12, bond the lower surface of the second core to the second U-shaped sheet. Apply insulating glue to the areas of the two side panels of the second U-shaped sheet that are not covered by the second core.

[0031] S15, coating insulating glue and conductive silver glue on one side of the third U-shaped thin plate according to the method of S11, and then bonding the coated side of the third U-shaped thin plate to the upper surface of the second core according to the method of S12 to complete the stacking of the second core;

[0032] S16. Repeat S14-S15 to continue stacking the third to Nth cores to obtain a first core package semi-finished product.

[0033] Preferably, the step S3 is specifically as follows: the two substrates are arranged with the tongues facing each other, the core package semi-finished product is sandwiched in the middle, and the anode plates and copper foils of the U-shaped thin plates on both sides of the core package semi-finished product are respectively bonded to the tongues through conductive silver glue.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] 1. The present invention uses U-shaped thin plates and cores to alternately stack to form a core package. At the same time, the outer dimensions of the U-shaped thin plates are set to be larger than the core size. After the U-shaped thin plates and the core are superimposed, the space not occupied by the core is sealed with insulating adhesive to provide support and protection for the core and prevent delamination. At the same time, it can also prevent resin from invading between the core layers during resin encapsulation of the core package, causing deterioration of the electrical performance of the capacitor.

[0036] 2. The present invention uses two substrates with pre-installed lead-out components on the two sides of the core package to sandwich them together, thereby realizing two-level lead-out of the core package and also being able to encapsulate and protect the upper and lower surfaces of the core package. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] 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.

[0038] FIG1 is a schematic structural diagram of a capacitor core pack according to the present invention;

[0039] FIG2 is a schematic structural diagram of a U-shaped thin plate in the present invention;

[0040] FIG3 is a schematic cross-sectional view of the U-shaped thin plate of the present invention;

[0041] FIG4 is a schematic structural diagram of a substrate in the present invention;

[0042] FIG5 is a schematic cross-sectional view of the substrate of the present invention;

[0043] FIG6 is a schematic structural diagram of a solid aluminum electrolytic capacitor according to the present invention;

[0044] FIG7 is a schematic cross-sectional view of a solid aluminum electrolytic capacitor according to the present invention;

[0045] FIG8 is a schematic flow chart of a method for preparing a solid aluminum electrolytic capacitor according to the present invention.

[0046] In the accompanying drawings, the components represented by each reference numeral are listed as follows: 1. Core; 2. U-shaped thin plate; 21. Anode plate; 22. Cathode plate; 23. Through hole; 24. U-shaped copper foil; 3. Base plate; 31. Rectangular protrusion; 4. Lead-out portion; 41. Tongue; 42. Connecting portion; 43. Pin; 5. Resin shell; 6. Waterproof coating. DETAILED DESCRIPTION

[0047] 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.

[0048] Referring to Figures 1-5, the first technical solution provided by the present invention is:

[0049] A capacitor core package includes N cores 1, N+1 U-shaped thin plates 2, and two base plates 3. The cross-sectional area of ​​the U-shaped thin plates 2 is larger than that of the cores 1. The N+1 U-shaped thin plates 2 and the N cores 1 are alternately stacked in sequence to form a core package semi-finished product. The anode portions of two adjacent cores 1 are electrically connected, and the cathode portions of two adjacent cores 1 are electrically connected. When the U-shaped thin plates 2 and the cores 1 are stacked, the space between the U-shaped thin plates 2 and the cores 1 that is not in contact is filled with insulating glue.

[0050] Two lead-out portions 4 are symmetrically provided at opposite ends of the substrate 3 . The two substrates 3 are respectively adhered to opposite sides of the core package semi-finished product, and the lead-out portions 4 at both ends of the substrate 3 are respectively electrically connected to the anode and cathode of the core 1 .

[0051] Specifically, the opposite ends of the U-shaped thin plate 2 are respectively an anode plate 21 and a cathode plate 22, and the anode plate 21 and the cathode plate 22 are connected by two side plates. The anode plate 21 and the anode portion of the core 1 are both penetrated by a through hole 23. When the U-shaped thin plate 2 and the core 1 are stacked, the through holes 23 are aligned and connected to each other, and the through holes 23 are filled with conductive silver paste.

[0052] A U-shaped copper foil 24 is inserted on the outside of the cathode plate 22, and the opening of the U-shaped copper foil 24 is set away from the anode plate 21. When the U-shaped thin plate 2 and the core 1 are stacked, the upper and lower sides of the U-shaped copper foil 24 are respectively in contact with the cathode part of the adjacent core 1 and electrically connected.

[0053] From the above description, it can be seen that the cathode part of each core is electrically conductive in parallel through the U-shaped copper foil pre-installed on the cathode plate surface of the adjacent upper and lower U-shaped thin plates, and the area of ​​the two adjacent U-shaped thin plates not covered by the cathode part of the core is sealed by insulating glue to prevent the resin packaging material from invading from the interlayer of the cathode part of the core, thereby avoiding leakage current and increased ESR.

[0054] Specifically, one end of the anode plate 21 close to the cathode plate 22 is flush with the end of the barrier glue of the core 1 close to the cathode part, the length of the anode plate 21 is 100%-120% of the total length of the anode part of the core 1 and the barrier glue, and the width of the anode plate 21 is 120%-150% of the width of the core 1;

[0055] The length of the cathode portion of each core 1 sandwiched between the cathode plates 22 of the two adjacent U-shaped thin plates 2 is 20%-50% of the length of the cathode portion; the width of the cathode plate 22 is 60%-80% of the width of the core 1;

[0056] The sum of the length of the hollowed-out portion of the U-shaped thin plate 2 and the length of the cathode plate 22 is 110%-120% of the length of the cathode portion of the core 1 , and the width of the U-shaped thin plate 2 is 120%-150% of the width of the core 1 .

[0057] From the above description, it can be seen that: the length and width of the anode plate are set within this range, so that after the core and the U-shaped thin plate are stacked, there is still enough space between the anode plate and the anode part of the core to fill with insulating glue, thereby ensuring the effect of sealing the anode part of the core; and the length and width of the cathode plate and the hollow part are set within this range, which can not only ensure the contact area between the cathode plate and the cathode part of the core, but also ensure that there is still enough space between the U-shaped thin plate and the cathode part of the core after stacking to fill with insulating glue, thereby ensuring the effect of sealing the cathode part of the core.

[0058] Specifically, the lead-out portion 4 includes a tongue 41, a connecting portion 42 and a pin 43. The tongue 41 and the pin 43 are arranged in parallel on two opposite surfaces of the substrate 3, and the tongue 41 is electrically connected to the core package semi-finished product. The connecting portion 42 is passed through the inside of the substrate 3, and the opposite ends of the connecting portion 42 are respectively vertically connected to the tongue 41 and the pin 43 and are electrically conductive.

[0059] Specifically, a rectangular protrusion 31 is provided on the side of the substrate 3 away from the core package semi-finished product, the length and width of the rectangular protrusion 31 are 80%-90% of the length and width of the substrate 3 respectively, and the height of the rectangular protrusion 31 is 0.3mm-0.5mm. The tongue 41 is provided on the side of the substrate 3 where the rectangular protrusion 31 is not provided, and one end of the tongue 41 is flush with one end of the substrate 3. The pin 43 is horizontally provided on the surface of the rectangular protrusion 31, and one end of the pin 43 is flush with one end of the rectangular protrusion 31.

[0060] From the above description, it can be seen that a rectangular protrusion is provided on one side surface of the substrate so that the outer surface of the substrate can form a step structure for the packaging resin to wrap, which not only improves the bonding strength between the resin and the core package semi-finished product and the substrate, but also extends the external water vapor intrusion channel, which is beneficial to improving the moisture resistance of the capacitor.

[0061] Specifically, the distance between the edges of the two tongues 41 located on the same substrate 3 is 40%-70% of the length of the substrate 3, and the distance between the edges of the two pins 43 located on the same substrate 3 is 40%-60% of the length of the rectangular protrusion 31 of the substrate 3.

[0062] From the above description, it can be seen that the spacing between the tongues within this range can prevent the core package semi-finished product from causing the positive and negative poles to be conductive during the bonding process with the substrate, thereby causing the capacitor to short-circuit; the distance between the pins is set within this range to prevent the capacitor finished product from causing the positive and negative poles to be conductive during the welding on the client board, thereby causing the capacitor to short-circuit.

[0063] As shown in Figures 6-7, the second technical solution provided by the present invention is:

[0064] A double-substrate laminated solid-state aluminum electrolytic capacitor includes a resin shell 5, a waterproof coating 6 and a capacitor core package. The waterproof coating 6 is coated on the four side surfaces of the capacitor core package. The resin shell 5 wraps around the waterproof coating 6 and the portion of the substrate 3 in the capacitor core package except for the rectangular raised portion 31. The four sides of the rectangular raised portion 31 of the substrate 3 are wrapped inside the resin shell 5, and the surface of the rectangular raised portion 31 of the substrate 3 where the pin 43 is provided is exposed from the resin shell 5.

[0065] From the above description, it can be seen that: when packaging the capacitor, a waterproof coating is pre-prepared on the surface of the core package and then the packaging protection is performed. This can not only improve the moisture resistance of the core package but also avoid damage caused by direct contact between the resin and the core in the traditional structure. In addition, the lead-out components are pre-placed in the U-shaped thin plate and the substrate, so that the pin bending and forming process can be eliminated during the preparation of the capacitor, preventing the increase in leakage current caused by the forming process, which is beneficial to improving the industrial yield. At the same time, the dual-substrate packaging lead-out design is adopted, so that the front and back sides of the pin structure are symmetrical, and there is no need to distinguish between the front and back sides when soldering on the client board.

[0066] Please refer to FIG8 , the third technical solution provided by the present invention is:

[0067] A method for preparing a double-substrate laminated solid aluminum electrolytic capacitor, the method comprising the following steps:

[0068] S1: Alternately stacking N+1 U-shaped sheets 2 and N cores 1 from bottom to top according to the designed number of layers, and electrically connecting the U-shaped copper foil 24 on the U-shaped sheets 2 to the cathode portions of two adjacent cores 1 to form a first core package semi-finished product;

[0069] S2: Drilling a through hole 23 at one end of the first core package semi-finished product near the anode portion of the core 1, which continuously penetrates the anode plate 21 of the N+1 U-shaped thin plates 2 and the anode portions of the N cores 1, and filling the through hole 23 with conductive silver paste to ensure electrical conduction between the anode portions of the N cores 1, thereby obtaining a core package semi-finished product;

[0070] S3: Bonding the upper and lower surfaces of the semi-finished core package to an external substrate 3 to obtain a capacitor core package;

[0071] S4: Coating the four sides of the capacitor core with a waterproof material to form a waterproof coating 6;

[0072] S5: The side surfaces of the capacitor core package and the edges of the substrate 3 are encapsulated with epoxy resin to form a resin shell 5, thereby obtaining a double-substrate laminated solid aluminum electrolytic capacitor.

[0073] Specifically, the method for stacking the core 1 and the U-shaped thin plate 2 in step S1 is as follows:

[0074] S11, coating insulating glue on one side of the anode plate 21 of the first U-shaped thin plate 2, and coating conductive silver glue on the U-shaped copper foil 24 of the cathode plate 22 on the same side;

[0075] S12. Bond the lower surface of the first core 1 to the first U-shaped sheet 2, so that the anode portion of the core 1 and the barrier adhesive are bonded to the anode plate 21 of the first U-shaped sheet 2, and the end of the anode plate 21 close to the cathode plate 22 is flush with the end of the barrier adhesive close to the cathode portion. At the same time, the cathode portion of the core 1 is bonded to and electrically connected to the U-shaped copper foil 24 on the cathode plate 22 of the first U-shaped sheet 2, and then apply insulating adhesive to the areas of the two side plates of the first U-shaped sheet 2 not covered by the first core 1;

[0076] S13. Apply insulating glue and conductive silver glue respectively on one side of the second U-shaped thin plate 2 according to the method of S11. Then, adhere the glue-coated side of the second U-shaped thin plate 2 to the upper surface of the first core 1 according to the method of S12. The width of the area where the two ends of the cathode portion of the first core 1 are sandwiched by the two side plates of the upper and lower adjacent U-shaped thin plates 2 are equal. The stacking of the first core is completed.

[0077] S14. Following the method of S11, apply insulating glue and conductive silver glue to the other surface of the second U-shaped sheet 2, respectively. Following the method of S12, bond the lower surface of the second core 1 to the second U-shaped sheet 2. Apply insulating glue to the areas of the two side panels of the second U-shaped sheet 2 not covered by the second core 1.

[0078] S15. Apply insulating glue and conductive silver glue to one side of the third U-shaped thin plate 2 according to S11, and then adhere the glue-coated side of the third U-shaped thin plate 2 to the upper surface of the second core 1 according to S12 to complete the stacking of the second core 1.

[0079] S16. Repeat S14-S15 to continue stacking the third to Nth cores 1 to obtain a first core package semi-finished product.

[0080] Specifically, step S3 is as follows: the two substrates 3 are arranged with the tongue 41 facing each other, the core package semi-finished product is sandwiched in the middle, and the anode plate 21 and the U-shaped copper foil 24 of the U-shaped thin plate 2 on both sides of the core package semi-finished product are respectively bonded to the tongue 41 through conductive silver glue.

[0081] The first embodiment of the present invention is (as shown in Figures 1-5):

[0082] A capacitor core pack includes two cores 1, three U-shaped thin plates 2, and two base plates 3. The cross-sectional area of ​​the U-shaped thin plates 2 is larger than that of the cores 1. The opposite ends of the U-shaped thin plates 2 are respectively an anode plate 21 and a cathode plate 22, and the anode plate 21 and the cathode plate 22 are connected by two side plates. The length of the anode plate 21 is 110% of the total length of the anode portion of the core 1 and the barrier adhesive, and the width of the anode plate 21 is 135% of the width of the core 1. The length of the cathode plate 22 is 35% of the length of the cathode portion of the core 1, and the width of the cathode plate 22 is 85% of the width of the core 1. The sum of the length of the hollow portion in the middle of the U-shaped thin plates 2 and the length of the cathode plate 22 is 115% of the length of the cathode portion of the core 1, and the width of the U-shaped thin plates 2 is 135% of the width of the core 1.

[0083] Three U-shaped sheets 2 and two cores 1 are stacked alternately in sequence to form a core package semi-finished product, and the anode portions of two adjacent cores 1 are electrically connected. The electrical connection structure between the anodes is as follows: the anode plate 21 and the anode portion of the core 1 are both penetrated by a through hole 23. When the U-shaped sheets 2 and the core 1 are stacked, the through holes 23 are aligned and connected to each other, and the through holes 23 are filled with conductive silver paste. The end of the anode plate 21 close to the cathode plate 22 is flush with the end of the core 1 barrier glue close to the cathode portion.

[0084] When the U-shaped sheet 2 and the core 1 are stacked, the cathode portions of two adjacent cores 1 are electrically connected. The electrical connection structure between the cathodes is as follows: a U-shaped copper foil 24 is inserted on the outside of the cathode plate 22, and the opening of the U-shaped copper foil 24 is set away from the anode plate 21. When the U-shaped sheet 2 and the core 1 are stacked, the upper and lower sides of the U-shaped copper foil 24 are in contact with the cathode portions of adjacent cores 1 and are electrically connected.

[0085] When the U-shaped thin plates 2 and the core 1 are stacked, the length of the cathode portion of each core 1 sandwiched between the cathode plates 22 of the two adjacent U-shaped thin plates 2 above and below is 35% of the length of the cathode portion; the width of the cathode plate 22 is 70% of the width of the core 1, and the width of the area sandwiched between the two side plates of the two adjacent U-shaped thin plates 2 above and below is equal.

[0086] When the U-shaped sheet 2 and the core 1 are stacked, the space between the U-shaped sheet 2 and the core 1 that is not in contact is filled with insulating glue;

[0087] Two lead-out portions 4 are symmetrically provided at opposite ends of the substrate 3. The two substrates 3 are respectively adhered to opposite sides of the core package semi-finished product, and the lead-out portions 4 at both ends of the substrate 3 are respectively electrically connected to the conductive silver paste of the anode portion and the U-shaped copper foil 24 of the cathode portion of the core 1. The lead-out portions 4 include a tongue 41, a connecting portion 42, and a pin 43. The tongue 41 and the pin 43 are arranged parallel to two opposite surfaces of the substrate 3, and the tongue 41 is electrically connected to the core package semi-finished product. The connecting portion 42 is provided inside the substrate 3, and the opposite ends of the connecting portion 42 are respectively perpendicularly connected to the tongue 41 and the pin 43 and electrically conductive.

[0088] In this embodiment, a rectangular raised portion 31 is provided on the side of the substrate 3 away from the core package semi-finished product. The length and width of the rectangular raised portion 31 are 85% of the length and width of the substrate 3 respectively, and the height of the rectangular raised portion 31 is 0.4 mm. The tongue portion 41 is provided on the side of the substrate 3 where the rectangular raised portion 31 is not provided, and one end of the tongue portion 41 is flush with one end of the substrate 3. The pin 43 is horizontally provided on the surface of the rectangular raised portion 31, and one end of the pin 43 is flush with one end of the rectangular raised portion 31.

[0089] The distance between the edges of the two tongues 41 located on the same substrate 3 and adjacent to each other is 55% of the length of the substrate 3 ; the distance between the edges of the two pins 43 located on the same substrate 3 and adjacent to each other is 50% of the length of the rectangular raised portion 31 of the substrate 3 ; the width of the tongue 41 is 90% of the width of the substrate 3 ; and the width of the pin 43 is 95% of the width of the rectangular raised portion 31 ;

[0090] In this embodiment, the material of the U-shaped thin plate 2 is a polymer insulating material, preferably a polyimide (PI) film;

[0091] In this embodiment, the substrate 3 is made of an insulating material, preferably an epoxy laminated glass cloth board (FR-4);

[0092] In this embodiment, the lead portion 4 is made of copper or copper alloy;

[0093] In this embodiment, a tin layer is provided on the surface of the pin 43 away from the rectangular protrusion 31 .

[0094] The second embodiment of the present invention is (shown in Figures 1-7):

[0095] A double-substrate laminated solid-state aluminum electrolytic capacitor includes a resin housing 5, a waterproof coating 6, and a capacitor core package according to a first embodiment. The waterproof coating 6 is applied to four sides of the capacitor core package. The resin housing 5 encloses the waterproof coating 6 and the portion of the substrate 3 in the capacitor core package excluding the rectangular raised portion 31. The four sides of the rectangular raised portion 31 of the substrate 3 are enclosed within the resin housing 5, and the surface of the rectangular raised portion 31 of the substrate 3 where the pins 43 are located is exposed from the resin housing 5.

[0096] In this embodiment, the waterproof material constituting the waterproof coating 6 can be one of polyvinyl alcohol, polyurethane, polyacrylate, polyvinyl acetate, and silicone rubber, preferably silicone rubber.

[0097] The third embodiment of the present invention is (shown in Figures 1-8):

[0098] This embodiment is used to prepare the double-substrate laminated solid aluminum electrolytic capacitor in Example 2. The specific method is as follows:

[0099] S1: According to the designed number of layers, three U-shaped sheets 2 and two cores 1 are alternately stacked from bottom to top, and the U-shaped copper foil 24 on the U-shaped sheet 2 is electrically connected to the cathode parts of the two adjacent cores 1 to form a first core package semi-finished product. The stacking method is specifically as follows:

[0100] S11, coating insulating glue on one side of the anode plate 21 of the first U-shaped thin plate 2, and coating conductive silver glue on the U-shaped copper foil 24 of the cathode plate 22 on the same side;

[0101] S12. Bond the lower surface of the first core 1 to the first U-shaped sheet 2, so that the anode portion of the core 1 and the barrier adhesive are bonded to the anode plate 21 of the first U-shaped sheet 2, and the end of the anode plate 21 close to the cathode plate 22 is flush with the end of the barrier adhesive close to the cathode portion. At the same time, the cathode portion of the core 1 is bonded to and electrically connected to the U-shaped copper foil 24 on the cathode plate 22 of the first U-shaped sheet 2, and then apply insulating adhesive to the areas of the two side plates of the first U-shaped sheet 2 not covered by the first core 1;

[0102] S13. Apply insulating glue and conductive silver glue respectively on one side of the second U-shaped thin plate 2 according to the method of S11. Then, adhere the glue-coated side of the second U-shaped thin plate 2 to the upper surface of the first core 1 according to the method of S12. The width of the area where the two ends of the cathode portion of the first core 1 are sandwiched by the two side plates of the upper and lower adjacent U-shaped thin plates 2 are equal. The stacking of the first core is completed.

[0103] S14. Following the method of S11, apply insulating glue and conductive silver glue to the other surface of the second U-shaped sheet 2, respectively. Following the method of S12, bond the lower surface of the second core 1 to the second U-shaped sheet 2. Apply insulating glue to the areas of the two side panels of the second U-shaped sheet 2 not covered by the second core 1.

[0104] S15, coating one side of the third U-shaped sheet 2 with insulating glue and conductive silver glue respectively according to the method of S11, and then bonding the coated side of the third U-shaped sheet 2 to the upper surface of the second core 1 according to the method of S12, completing the stacking of the second core 1, and obtaining a first core package semi-finished product;

[0105] S2: Drill a through hole 23 at one end of the first core package semi-finished product near the anode portion of the core 1, which continuously penetrates the anode plate 21 of the three U-shaped thin plates 2 and the anode portions of the two cores 1. Fill the through hole 23 with conductive silver paste to ensure electrical conduction between the anode portions of the two cores 1, thereby obtaining a core package semi-finished product.

[0106] S3: The upper and lower surfaces of the core package semi-finished product are respectively bonded to an external substrate 3 to obtain a capacitor core package. The specific bonding method is as follows: the two substrates 3 are arranged with the sides provided with the tongue portion 41 facing each other, the core package semi-finished product is sandwiched in the middle, and the anode plate 21 and the U-shaped copper foil 24 of the U-shaped thin plate 2 on both sides of the core package semi-finished product are respectively bonded to the tongue portion 41 using conductive silver glue;

[0107] S4: Coating a silicone rubber waterproof material on four sides of the capacitor core package to form a waterproof coating 6;

[0108] S5: Use epoxy resin to encapsulate the side surfaces of the capacitor core package and the edges of the substrate 3 to form a resin shell 5, and produce a double-substrate laminated solid aluminum electrolytic capacitor. Specifically, the resin shell 5 covers the capacitor core package, the waterproof coating 6, and the portion of the substrate 3 in the capacitor core package except for the rectangular protrusion 31; the four sides of the rectangular protrusion 31 are wrapped in the resin shell 5; and the surface of the rectangular protrusion 31 with the pin 43 is exposed from the resin shell 5.

[0109] In this embodiment, the preparation method of the core 1 is: punching the chemical foil into long strips, coating the barrier glue to divide the anode area (anode part) and the cathode area, and sequentially preparing a conductive polymer layer, a conductive carbon paste layer and a conductive silver paste layer on the surface of the cathode area to form the cathode part to obtain the core.

[0110] The present invention differs from the conventional lead-out method of a planar metal lead frame. It utilizes a core package structure in which U-shaped thin plates and cores are alternately stacked. Parallel electrical conduction is achieved between the cathode portions of each core via U-shaped copper foil pre-placed on one end surface of the upper and lower U-shaped thin plates adjacent to each core. The cathode lead-out is then achieved by connecting the U-shaped copper foils of the two outermost U-shaped thin plates of the core package to an external substrate pre-placed with a lead-out component. The outer dimensions of the U-shaped thin plates are larger than the core dimensions. After being superimposed on the core, the space not occupied by the core is sealed with insulating adhesive to provide support and protection for the core, preventing delamination and preventing resin from invading between core layers and causing electrical performance degradation.

[0111] The present invention sandwiches two substrates with pre-installed lead-out components to form a core package, achieving lead-out of the positive and negative poles of the core package while encapsulating and protecting the upper and lower surfaces of the core package. After a waterproof coating is pre-prepared around the core package, the surrounding sides of the core package are encapsulated and protected with a resin encapsulation material. This structure not only improves the moisture resistance of the core package, but also avoids damage caused by direct contact of the resin with the core in traditional structures. A stepped structure is provided around the substrate for encapsulation resin wrapping, which not only improves the bonding strength of the resin with the core package and the substrate, but also extends the channel for external water vapor intrusion, which is conducive to improving the moisture resistance of the capacitor.

[0112] The traditional process of using a flat metal lead frame to lead out a structure involves bending and forming the leads exposed outside the resin housing to form external terminals, which causes mechanical impact on the core package. The present invention pre-installs the lead components in the U-shaped thin plate and substrate, eliminating the pin bending and forming process, preventing the increase in leakage current caused by the forming process, and is conducive to improving the industrial yield rate.

[0113] The advantages of the structure of the present invention are that it adopts double-sided substrate packaging and lead-out, and the pin structure is symmetrical on the front and back sides, so there is no need to distinguish between the front and back sides when welding on the upper board (the traditional structure has only single-sided pins).

[0114] 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 capacitor core package, characterized in that: The invention comprises N cores (1), N+1 U-shaped thin plates (2) and two substrates (3), wherein the cross-sectional area of ​​the U-shaped thin plates (2) is greater than the cross-sectional area of ​​the cores (1), the N+1 U-shaped thin plates (2) and the N cores (1) are stacked alternately in sequence to form a core package semi-finished product, and the anode parts of two adjacent cores (1) are electrically connected, and the cathode parts of two adjacent cores (1) are electrically connected, and when the U-shaped thin plates (2) and the cores (1) are stacked, the space where the U-shaped thin plates (2) are not in contact with the cores (1) is filled with insulating glue; Two lead-out portions (4) are symmetrically provided at opposite ends of the substrate (3); the two substrates (3) are respectively adhered to opposite side surfaces of the core package semi-finished product; and the lead-out portions (4) at both ends of the substrate (3) are respectively electrically connected to the anode portion and cathode portion of the core (1).

2. A capacitor core pack according to claim 1, characterized in that: The two opposite ends of the U-shaped thin plate (2) are respectively an anode plate (21) and a cathode plate (22), and the anode plate (21) and the cathode plate (22) are connected via two side plates, and the anode plate (21) and the anode portion of the core (1) are both penetrated by a through hole (23), and when the U-shaped thin plate (2) and the core (1) are stacked, the through holes (23) are aligned with each other and connected, and the inside of the through hole (23) is filled with conductive silver paste; A U-shaped copper foil (24) is inserted on the outside of the cathode plate (22), and the opening of the U-shaped copper foil (24) is arranged away from the anode plate (21). When the U-shaped thin plate (2) and the core (1) are stacked, the upper and lower side surfaces of the U-shaped copper foil (24) are respectively in contact with the cathode part of the adjacent core (1) and are electrically connected.

3. A capacitor core pack according to claim 2, characterized in that: One end of the anode plate (21) close to the cathode plate (22) is flush with one end of the barrier glue of the core (1) close to the cathode portion, the length of the anode plate (21) is 100%-120% of the sum of the lengths of the anode portion of the core (1) and the barrier glue, and the width of the anode plate (21) is 120%-150% of the width of the core (1); The length of the cathode portion of each core (1) sandwiched between the cathode plates (22) of the two adjacent upper and lower U-shaped thin plates (2) is 20%-50% of the length of the cathode portion; the width of the cathode plate (22) is 60%-80% of the width of the core (1); The sum of the length of the hollowed-out portion in the middle of the U-shaped thin plate (2) and the length of the cathode plate (22) is 110%-120% of the length of the cathode portion of the core (1), and the width of the U-shaped thin plate (2) is 120%-150% of the width of the core (1).

4. A capacitor core pack according to claim 1, characterized in that: The lead-out portion (4) comprises a tongue portion (41), a connecting portion (42) and a pin (43); the tongue portion (41) and the pin (43) are arranged in parallel on two opposite surfaces of the substrate (3), and the tongue portion (41) is electrically connected to the core package semi-finished product; the connecting portion (42) is arranged inside the substrate (3), and the opposite ends of the connecting portion (42) are respectively vertically connected to the tongue portion (41) and the pin (43) and are electrically conductive.

5. A capacitor core pack according to claim 4, characterized in that: A rectangular protrusion (31) is provided on a side of the substrate (3) away from the core package semi-finished product, the length and width of the rectangular protrusion (31) are respectively 80%-90% of the length and width of the substrate (3), the height of the rectangular protrusion (31) is 0.3 mm-0.5 mm, the tongue (41) is provided on a side of the substrate (3) where the rectangular protrusion (31) is not provided, and one end of the tongue (41) is flush with one end of the substrate (3), and the pin (43) is horizontally provided on the surface of the rectangular protrusion (31), and one end of the pin (43) is flush with one end of the rectangular protrusion (31).

6. A capacitor core pack according to claim 5, characterized in that: The distance between the mutually adjacent edges of the two tongues (41) located on the same substrate (3) is 40%-70% of the length of the substrate (3), and the distance between the mutually adjacent edges of the two pins (43) located on the same substrate (3) is 40%-60% of the length of the rectangular protrusion (31) of the substrate (3).

7. A double-substrate laminated solid aluminum electrolytic capacitor, characterized in that: It comprises a resin shell (5), a waterproof coating (6) and a capacitor core package according to any one of claims 1 to 6, wherein the waterproof coating (6) is coated on four side surfaces of the capacitor core package, the resin shell (5) wraps the waterproof coating (6) and a portion of a substrate (3) in the capacitor core package excluding a rectangular raised portion (31), the four sides of the rectangular raised portion (31) of the substrate (3) are wrapped inside the resin shell (5), and the surface of the rectangular raised portion (31) of the substrate (3) provided with a pin (43) is exposed from the resin shell (5).

8. A method for preparing a double-substrate laminated solid aluminum electrolytic capacitor, characterized in that: The preparation method comprises the following steps: S1: According to the designed number of layers, N+1 U-shaped thin plates (2) and N cores (1) are alternately stacked from bottom to top, and the U-shaped copper foil (24) on the U-shaped thin plates (2) is electrically connected to the cathode parts of two adjacent cores (1), so as to form a first core package semi-finished product; S2: drilling a through hole (23) that continuously penetrates the anode plate (21) of N+1 U-shaped thin plates (2) and the anode parts of N cores (1) at one end of the first core package semi-finished product close to the anode part of the core (1), and filling the through hole (23) with conductive silver paste so that the anode parts of the N cores (1) are electrically connected to each other, thereby obtaining a core package semi-finished product; S3: bonding the upper and lower surfaces of the semi-finished core package to an external substrate (3) respectively to obtain a capacitor core package; S4: coating the four sides of the capacitor core package with a waterproof material to form a waterproof coating (6); S5: The side surfaces of the capacitor core package and the edges of the substrate (3) are encapsulated with epoxy resin to form a resin shell (5), thereby obtaining a double-substrate laminated solid aluminum electrolytic capacitor.

9. The method for preparing a double-substrate laminated solid aluminum electrolytic capacitor according to claim 8, characterized in that: The stacking method of the core (1) and the U-shaped thin plate (2) in step S1 is specifically as follows: S11, coating insulating glue on one side of the anode plate (21) of the first U-shaped thin plate (2), and coating conductive silver glue on the U-shaped copper foil (24) of the cathode plate (22) on the same side; S12, bonding the lower surface of the first core (1) to the first U-shaped thin plate (2), so that the anode part of the core (1) and the barrier glue are bonded to the anode plate (21) of the first U-shaped thin plate (2), and the end of the anode plate (21) close to the cathode plate (22) is flush with the end of the barrier glue close to the cathode part, and at the same time, the cathode part of the core (1) is bonded to the U-shaped copper foil (24) on the cathode plate (22) of the first U-shaped thin plate (2) and electrically connected thereto, and then insulating glue is applied to the areas of the two side plates of the first U-shaped thin plate (2) that are not covered by the first core (1); S13, coating one side of the second U-shaped sheet (2) in the manner of S11 Insulating glue and conductive silver glue are applied, and then the glue-coated side of the second U-shaped thin plate (2) is bonded to the upper surface of the first core (1) in accordance with the method of S12, and the width of the area where the two ends of the cathode portion of the first core (1) are sandwiched by the two side plates of the upper and lower U-shaped thin plates (2) adjacent to it are equal, so as to complete the stacking of the first core; S14, according to the method of S11, respectively apply insulating glue and conductive silver glue on the other side of the second U-shaped thin plate (2); according to the method of S12, adhere the lower surface of the second core (1) to the second U-shaped thin plate (2); and apply insulating glue on the areas of the two side plates of the second U-shaped thin plate (2) that are not covered by the second core (1); S15, according to the method of S11, respectively coating insulating glue and conductive silver glue on one side of the third U-shaped thin plate (2), and then according to the method of S12, bonding the glue-coated side of the third U-shaped thin plate (2) to the upper surface of the second core (1), thereby completing the stacking of the second core (1); S16, repeat S14-S15, continue to complete the stacking of the third to Nth cores (1), and obtain the first core package semi-finished product.

10. The method for preparing a double-substrate laminated solid aluminum electrolytic capacitor according to claim 8, characterized in that: The step S3 specifically comprises: making the two substrates (3) face each other with the tongue (41), sandwiching the core package semi-finished product in the middle, and bonding the anode plate (21) and the U-shaped copper foil (24) of the U-shaped thin plate (2) on both sides of the core package semi-finished product to the tongue (41) respectively by means of conductive silver glue.

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