High-temperature-resistant capacitor

Abstract

The invention provides a high-temperature-resistant capacitor, and the capacitor comprises a core which comprises a first positive electrode part and a first negative electrode part; the sealing assembly comprises a ceramic body and a cover assembly, the ceramic body is provided with an opening, the cover assembly covers the opening of the ceramic body, a cavity is defined between the cover assembly and the ceramic body, and the core is arranged in the cavity; a second positive electrode part and a second negative electrode part are arranged on the inner side of the ceramic body, a positive electrode bonding pad and a negative electrode bonding pad are arranged on one outer surface of the ceramic body, a pin of the positive electrode bonding pad penetrates through the ceramic body to be electrically connected with the second positive electrode part, and a pin of the negative electrode bonding pad penetrates through the ceramic body to be electrically connected with the second negative electrode part; the second positive electrode part is electrically connected with the first positive electrode part, the second negative electrode part is electrically connected with the first negative electrode part, and the whole cavity is in an airtight state. According to the high-temperature-resistant capacitor, compared with a sealing assembly made of all metal, the overall height of the high-temperature-resistant capacitor can be further reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of capacitors, and more particularly to a high temperature resistant capacitor. Background Art

[0002] With the rapid development of science and technology in recent years, electronic products are rapidly developing towards thin, light, small, and surface mounted. With the development of high-density design, the demand for capacitor capacity continues to increase, and the temperature of product boards also continues to rise.

[0003] Traditional plastic-encapsulated laminated aluminum electrolytic capacitors (SP-CAP) can meet high specific capacitance requirements. However, the external encapsulation material of traditional SP-CAP capacitors is epoxy resin, and epoxy resin has poor high temperature resistance and a non-airtight structure. Air can continue to enter the package, causing the cathode material (conductive polymer) to crack. Therefore, when used at an average temperature above 60°C, its equivalent series resistance (ESR) will increase significantly. Long-term operation under high temperature conditions can easily lead to a decrease in protection functions and cause device failure. For this reason, plastic-encapsulated laminated aluminum electrolytic capacitors are prohibited from use in high temperature scenarios.

[0004] Therefore, it is urgent to provide a high temperature resistant capacitor that can meet the increasing miniaturization requirements of current electronic devices. Summary of the invention

[0005] In view of this, an object of the present invention is to provide a high temperature resistant capacitor that is both high temperature resistant and miniaturized.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] According to an embodiment of the present application, a high temperature resistant capacitor includes:

[0008] a core, the core comprising a first positive electrode portion and a first negative electrode portion;

[0009] A sealing assembly, the sealing assembly comprising a ceramic body and a cover assembly, the ceramic body having an opening, the cover assembly covering the opening of the ceramic body and defining a cavity between the cover assembly and the ceramic body,

[0010] In which, the core is arranged in the cavity, and the second positive electrode part and the second negative electrode part are respectively provided on the inner side of the ceramic body, and a positive electrode pad and a negative electrode pad are respectively provided on an outer surface of the ceramic body, the pin of the positive electrode pad passes through the ceramic body and is electrically connected to the second positive electrode part, the pin of the negative electrode pad passes through the ceramic body and is electrically connected to the second negative electrode part, the second positive electrode part is electrically connected to the first positive electrode part and the second negative electrode part is electrically connected to the first negative electrode part, and the cavity as a whole is in an airtight state.

[0011] That is to say, according to the high-temperature resistant capacitor of the present application, a ceramic body and a cover assembly are used as a sealing component. Compared with a sealing component made of all metal, since the ceramic body itself has insulating properties, there is no need to set an insulating gasket between the ceramic body and the core, thereby further compressing the overall height; in addition, the ceramic body itself has certain mechanical strength and rigidity, and compared with ductile metal, it can be made thinner, thereby further reducing the overall height; and, compared with the all-metal sealing component, the processing technology of the electrical connection between the ceramic body and the core becomes simpler and easier to operate.

[0012] Here, it should be noted that the so-called "the cavity is in an airtight state as a whole" means that the packaging method of the ceramic body and the cover assembly is airtight, and the positive electrode pad and the negative electrode pad are not airtightly packaged with the ceramic body while passing through the ceramic body, so that the sealing assembly can achieve airtight protection for the core arranged inside it, and prevent gas from entering the interior and causing cracking reaction of the cathode material of the core. In other words, the high temperature resistant capacitor of the present application not only achieves high temperature resistance by adopting a high temperature resistant sealing assembly, but also can withstand harsh use environments such as high humidity because the cavity is in an airtight state as a whole.

[0013] According to some embodiments of the present application, the cover assembly is a ceramic part or a metal part.

[0014] That is to say, the entire sealing component can be made of all ceramics, or a combination of a ceramic body and a metal cover, and the specific selection can be made according to the space conditions of the application scenario.

[0015] According to some embodiments of the present application, the core also includes a stacked body, which includes a plurality of stacked single sheets, each of which includes a substrate, one end of the substrate being a positive electrode and the other end being a negative electrode, a silver layer is provided on the upper and lower surfaces of the negative electrode of the single sheet, and a shielding layer is provided on the upper and lower surfaces of the positive electrode of the single sheet and adjacent to the silver layer.

[0016] That is, the high temperature resistant capacitor of the present application can be applied to a stacked capacitor. In a stacked capacitor, the core adopts a stacked structure, and each single piece in the stack includes a substrate, which is an aluminum substrate in the case of an aluminum electrolytic capacitor and a tantalum substrate in the case of a tantalum capacitor.

[0017] According to some embodiments of the present application, a plurality of the single-piece positive electrodes are connected in parallel and electrically connected to the first positive electrode portion, the first positive electrode portion extends from the stack, and the silver layer on a surface of the stack constitutes the first negative electrode portion.

[0018] That is, for the multilayer capacitor, the core thereof does not need to be separately provided with a first negative electrode portion for electrical connection with the sealing assembly, and electrical connection can be directly achieved by the silver layer provided on the surface of the multilayer body, thereby achieving further miniaturization.

[0019] Furthermore, the second positive electrode portion is a first conductor disposed inside the ceramic body, the height and position of the first conductor correspond to the first positive electrode portion, and the second negative electrode portion is a second conductor disposed inside the ceramic body.

[0020] That is to say, in a case where the first negative electrode portion is formed by a surface silver layer and the first positive electrode portion of the core is directly extended from the positive electrode of the laminate, the second positive electrode portion on the inner side of the ceramic body corresponds to the first positive electrode portion in height. In other words, after the first positive electrode portion extends out of the laminate, it can be directly electrically connected to the second positive electrode portion that matches it in height without any bending or other processing, thereby further compressing the overall height.

[0021] Furthermore, the first conductor is a metal boss, and the second conductor is a metal sheet.

[0022] The metal boss is used as the second positive electrode part, and the metal sheet is used as the second negative electrode part. The entire capacitor is simple to process and assemble, and has a stable structure and a long service life.

[0023] According to some other embodiments of the present application, the core further includes an insulating layer encapsulated outside the stack, and the first positive electrode portion and the first negative electrode portion respectively pass through the insulating layer from both ends of the stack and are folded and attached to a surface of the insulating layer.

[0024] That is to say, in addition to directly placing the core in the ceramic body, the core can also be packaged first and then placed in the ceramic body. In this case, the first positive electrode portion and the first negative electrode portion need to pass through the insulating layer from the laminate. In order to control the volume of the core as a whole to meet the miniaturization requirements, the first positive electrode portion and the first negative electrode portion can be folded and attached to the surface of the insulating layer after passing through the insulating layer.

[0025] Furthermore, a first groove and a second groove are respectively formed on a surface of the insulating layer corresponding to the first positive electrode portion and the first negative electrode portion, the depths of the first groove and the second groove respectively match the first positive electrode portion and the first negative electrode portion, and the ends of the first positive electrode portion and the first negative electrode portion away from the stack are respectively arranged in the first groove and the second groove.

[0026] That is to say, although the first positive electrode portion and the first negative electrode portion of the packaged core are attached to the surface of the insulating layer, the overall height of the core does not need to be increased by correspondingly arranging the first groove and the second groove on the insulating layer.

[0027] Furthermore, the second positive electrode portion and the second negative electrode portion are respectively a third conductor and a fourth conductor attached to the inner surface of the ceramic body.

[0028] Furthermore, the third conductor and the fourth conductor are metal sheets respectively. That is to say, in this case, it is only necessary to arrange metal sheets on the inner surface of the ceramic body as the corresponding second positive electrode part and second negative electrode part.

[0029] According to some embodiments of the present application, through holes are formed on the ceramic body corresponding to the positive electrode pad and the negative electrode pad, respectively, and the pin of the positive electrode pad is connected to the second positive electrode part through the through hole, and the pin of the negative electrode pad is connected to the second negative electrode part through the through hole, and the through hole and the pin are sealed by solder. That is to say, when preparing the ceramic body, holes can be punched in the blank forming stage, and then a ceramic body with through holes can be formed by sintering. Of course, holes can also be punched after sintering, but the processing difficulty and cost are relatively higher. On the other hand, when the positive electrode pad and the negative electrode pad pass through the through hole to connect the second positive electrode part and the second negative electrode part inside the ceramic body, in order to achieve airtightness, the through hole can be filled with solder. Compared with materials such as rubber, solder can withstand higher temperatures.

[0030] According to some embodiments of the present application, a valveable ring is welded to the upper edge of the ceramic body, and the ceramic body is connected to the cover assembly via the valveable ring.

[0031] By providing a valve ring and then connecting the cover assembly through the valve ring, an airtight connection between the ceramic body and the cover assembly can be achieved, and the process is relatively simple.

[0032] Furthermore, a tungsten-gold layer and a nickel layer are sequentially stacked between the upper edge of the ceramic body and the valve ring from the ceramic body upwards. By providing the tungsten-gold layer and the nickel layer as transition layers, the connection between the ceramic body and the cover assembly can be made stronger.

[0033] According to some embodiments of the present application, the material of the ceramic body is alumina. As the material of the ceramic body, common ceramics such as alumina ceramics, zirconia ceramics, and silicon carbide ceramics can be used, among which alumina ceramics are preferred due to their advantages such as low raw material cost and low sintering temperature.

[0034] According to some embodiments of the present application, a hydrophobic layer is disposed on the surface of the ceramic body, thereby further improving the high humidity resistance of the capacitor.

[0035] According to some embodiments of the present application, the overall height of the high temperature resistant capacitor is less than 2.5 mm. According to the high temperature resistant capacitor of the present application, the overall height can be controlled to be less than 2.5 mm, which is far superior to the stacked capacitors currently on the market and can further meet the requirements of miniaturization and thinness of electronic products. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A schematic structural diagram of a core of a high temperature resistant capacitor according to an embodiment of the present invention;

[0037] Figure 2 Schematic diagram of the structure of a ceramic body in a high temperature resistant capacitor according to an embodiment of the present invention, wherein (a) is a side view, (b) is a top view, and (c) is a side cross-sectional view;

[0038] Figure 3a A schematic diagram of a partial three-dimensional structure of a high temperature resistant capacitor according to an embodiment of the present invention;

[0039] Figure 3b is a schematic side cross-sectional view of a high temperature resistant capacitor according to an embodiment of the present invention;

[0040] Figure 4 Schematic diagram of the structure of a core of a high temperature resistant capacitor according to another embodiment of the present invention, wherein (a) is a side sectional view and (b) is a top view;

[0041] Figure 5 Schematic diagram of the structure of a body in a high temperature resistant capacitor according to another embodiment of the present invention, wherein (a) is a top view and (b) is a side cross-sectional view;

[0042] Figure 6 is a schematic structural diagram of a high temperature resistant capacitor according to another embodiment of the present invention;

[0043] Figure 7 is a SEM image of a welding position between a ceramic body and a valve ring in a high temperature resistant capacitor according to an embodiment of the present invention;

[0044] Figure 8 is a schematic diagram of a core structure according to an embodiment;

[0045] Fig. 9 FIG. 4 is a schematic structural diagram of a fully metal packaged capacitor according to another embodiment. DETAILED DESCRIPTION

[0046] To make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention.

[0047] The high temperature resistant capacitor (hereinafter referred to as capacitor) of the present application comprises: a core and a sealing assembly. The sealing assembly comprises a ceramic body and a cover assembly, and the cover assembly covers the opening of the ceramic body, thereby defining a cavity structure inside the sealing assembly. The core is arranged in the cavity, and the electrodes of the core are electrically connected to the outside world through the electrodes arranged on the ceramic body. The cavity of the sealing assembly is in an airtight state as a whole.

[0048] Figure 8 A laminated aluminum capacitor is shown. Figure 8 As shown, an insulating layer 16 of epoxy resin is encapsulated on the outer side of the core 1. The high temperature resistance of the capacitor needs to be further improved, and the height / size needs to be further reduced.

[0049] In some implementations, it is proposed to modify the epoxy resin material as the shell of the capacitor, and improve the ability of the resin material to combine with the positive and negative lead frames to enhance the high temperature resistance. However, even so, the capacitor can only meet the 10-year use requirement below 75°C, and cannot meet the 10-year lifespan above 75°C.

[0050] refer to Fig. 9 Based on a similar overall structure, a high-humidity resistant laminated aluminum electrolytic capacitor is proposed in other embodiments, which uses all-metal materials instead of epoxy resin for packaging design, thereby improving the moisture and heat resistance of the capacitor to meet the requirements of specifications such as 85°C / 85%RH-1000h. However, due to the influence of its processing technology and material properties, the metal shell 200 itself should have a certain plate thickness for all-metal material packaging, which limits the decrease in its overall height. In addition, in order to avoid a short circuit caused by direct contact of the core with the metal seat plate, an insulating gasket 300 must be provided between the metal seat plate and the core for all-metal material packaging, which further limits the compression space of the capacitor in height.

[0051] The capacitor provided according to the embodiment of the present application adopts a ceramic body 2, and by utilizing its high temperature resistance, insulation and the mechanical properties of the material itself, it can have better high temperature resistance than a capacitor made of epoxy resin material, and can be further compressed in height compared to a capacitor made of a metal body. In addition, by performing airtight packaging between the ceramic body and the cover assembly (such as a metal plate or a ceramic plate), the problem of increased ESR caused by decreased conductivity of the polymer material in the core in a hot oxygen environment can be solved.

[0052] Next, taking a multilayer capacitor as an example, a high temperature resistant capacitor (hereinafter sometimes referred to as a capacitor) according to the present application will be described in detail in conjunction with the accompanying drawings. Figure 1 FIG. 3 shows a schematic structural diagram of a high temperature resistant capacitor and a core 1 and a ceramic body 2 of one of the sealing components therein in a first embodiment. Figures 4 to 6 A schematic structural diagram of a high temperature resistant capacitor of a second embodiment and a core 1 and a ceramic body 2 of one of the sealing components therein is shown.

[0053] According to the high temperature resistant capacitor of the present application, for example, it can be any one of a laminated aluminum electrolytic capacitor, a cylindrical aluminum electrolytic capacitor, and a tantalum capacitor. That is to say, the high temperature resistant capacitor of the present application can be applied not only to laminated aluminum electrolytic capacitors, but also to cylindrical aluminum electrolytic capacitors and tantalum capacitors, and has a wide range of applications.

[0054] The following first describes the basically identical features of the two embodiments in conjunction with the accompanying drawings.

[0055] As shown in Figure 3 and Figure 6 As shown, the capacitor according to the present application includes a core 1 and a sealing assembly, wherein the sealing assembly includes a ceramic body 2 and a cover assembly. The ceramic body 2 has an opening, and the cover assembly 3 covers the opening of the ceramic body 2 to define a cavity between the cover assembly 3 and the ceramic body 2, and the core 1 is arranged in the cavity.

[0056] like Figure 1 and Figure 4 As shown, the core 1 includes a core positive electrode portion 11 (as an example of a first positive electrode portion) and a core negative electrode portion 12 (as an example of a first negative electrode portion).

[0057] According to some embodiments of the present application, taking a laminated aluminum electrolytic capacitor as an example, Figure 1 and Figure 4 As shown, the core 1 can be formed by growing a polymer material on one end (i.e., the end close to the negative electrode) of an aluminum foil (i.e., a substrate), then impregnating carbon on the polymer, and growing a silver material to form a silver layer 13, and then providing an insulating layer as a shielding layer 14 at the end 15 of the silver material close to the positive electrode to isolate the positive and negative electrodes, thereby forming a single sheet. Then, multiple single sheets are stacked to form a laminate. The electrode of the core 1 can be, for example, a metal conductor such as a copper sheet drawn out from the laminate.

[0058] like Figure 2 Figure (b) and Figure 5As shown in the middle (b) figure, a ceramic body positive electrode portion 21 (as an example of a second positive electrode portion) and a ceramic body negative electrode portion 22 (as an example of a second negative electrode portion) are respectively provided on the inner side of the ceramic body 2. A positive electrode pad 23 and a negative electrode pad 24 are respectively provided on an outer surface of the ceramic body 2. The pin of the positive electrode pad 23 passes through the ceramic body 2 and is electrically connected to the second ceramic body positive electrode portion 21. The pin of the negative electrode pad 24 passes through the ceramic body 2 and is electrically connected to the second ceramic body negative electrode portion 22. At the same time, the ceramic body positive electrode portion 21 on the inner side of the ceramic body 2 is electrically connected to the core positive electrode portion 11 of the core 1, and the ceramic body negative electrode portion 22 is electrically connected to the core negative electrode portion 12 of the core 1. In other words, the positive electrode of the core 1 is electrically connected to the positive electrode pad 23 located on the outside of the ceramic body 2 through the core positive electrode part 11 via the ceramic body positive electrode part 21, and the negative electrode of the core 1 is electrically connected to the negative electrode pad 24 located on the outside of the ceramic body 2 through the core negative electrode part 12 via the ceramic body negative electrode part 22.

[0059] In the design of the capacitor, although through holes need to be set on the ceramic body 2 of the capacitor to ensure the electrical connection between the external pads and the internal positive and negative electrodes, the cavity needs to be in an airtight state as a whole. In other words, the ceramic body 2 with the pads needs to meet the airtight requirements. After the ceramic body is matched with the cover assembly, an airtight cavity is formed.

[0060] According to some embodiments of the present application, through holes (not shown) are respectively formed on the ceramic body 2 corresponding to the positive electrode pad 23 and the negative electrode pad 24, and the pin of the positive electrode pad 23 is connected to the positive electrode part 21 of the second ceramic body through the through hole, and the pin of the negative electrode pad 24 is connected to the negative electrode part 22 of the second ceramic body through the through hole, and the through hole and the pin are sealed by solder.

[0061] The airtightness of the through-holes used to electrically connect the positive and negative electrode pads and the positive and negative electrodes of the internal ceramic body is ensured by means of high-temperature welding to fill the through-holes with solder.

[0062] It can be seen that according to the high temperature resistant capacitor of the present application, the ceramic body 2 and the cover assembly 3 are used as the sealing assembly. Compared with the sealing assembly made of all metal, since the ceramic body 2 itself has insulation, there is no need to set an insulating gasket between the ceramic body 2 and the core 1, thereby further compressing the overall height. In addition, the ceramic body 2 itself has a certain mechanical strength and rigidity. Compared with the ductile metal, it can be made thinner, thereby further reducing the overall height; and, compared with the all-metal sealing assembly, the processing technology of the electrical connection between the ceramic body 2 and the core 1 becomes simpler and easier to operate.

[0063] As shown in Figure 3 and Figure 6As shown, the cover assembly 3 matched with the ceramic body 2 can be, for example, a ceramic part or a metal part. In other words, the ceramic body 2 and the ceramic cover assembly 3 can be sealed to form a sealing assembly, or the ceramic body 2 and the metal cover assembly 3 can form a sealing assembly. In other words, the entire sealing assembly can be made of all ceramics, or a ceramic body and a metal cover can be combined. The specific selection can be made according to the setting space conditions of the application scenario.

[0064] For example, a plurality of through holes corresponding to the positive electrode pad 23 and the negative electrode pad 24 can be respectively provided. A porous connection channel is designed at the bottom of the ceramic body to ensure low impedance requirements and meet the strength requirements of the ceramic cavity without collapse or cracking.

[0065] In some embodiments, Figure 2 As shown, a valve ring 4 is welded to the upper edge of the ceramic body 2 , and the ceramic body 2 is connected to the cover assembly 3 through the valve ring 3 .

[0066] Furthermore, if Figure 7 As shown, a tungsten-gold layer and a nickel layer are stacked in sequence from the ceramic body 2 upward between the upper edge of the ceramic body 2 and the valve ring 4. The tungsten-gold layer has good bonding with the ceramic body, while the nickel layer has good bonding with the valve ring. At the same time, the tungsten-gold layer and the nickel layer can be well bonded. Therefore, the valve ring can be firmly bonded to the ceramic body by using the tungsten-gold layer and the nickel layer as transition layers.

[0067] The material of the ceramic body 2 may be, for example, alumina. Common ceramics such as alumina ceramics, zirconia ceramics, and silicon carbide ceramics may be used as the material of the ceramic body. Alumina ceramics are preferred because of their low raw material cost and low sintering temperature.

[0068] The surface of the ceramic body 2 may be provided with a hydrophobic layer, for example, thereby further improving the high humidity resistance of the capacitor.

[0069] According to the capacitor of the present application, the overall height can be controlled below 2.5 mm, which can further meet the requirements of thinness and miniaturization.

[0070] The following, combined Figure 1 FIG3 further describes the implementation details of the high temperature resistant capacitor of the first embodiment.

[0071] like Figure 1 As shown in FIG3 , in this embodiment, a plurality of single-piece positive electrodes are connected in parallel and electrically connected to a metal conductor extending from the laminate to form a core positive electrode portion 11 of the core; the silver layer on the surface of the laminate can be directly used to form a core negative electrode portion 12 of the core without the need for a separately extending or other form of negative electrode.

[0072] Accordingly, if Figure 2 As shown, in this embodiment, the ceramic body positive electrode portion 21 on the inner side of the ceramic body 2, which is used to be electrically connected to the core positive electrode portion 11 of the core 1, is configured as a first conductor arranged on the inner side of the ceramic body 2, and the height and position of the first conductor correspond to the core positive electrode portion 11 of the core 1, that is, when the core is assembled in the ceramic body 1, the core positive electrode portion 11 of the core and the first conductor on the inner side of the ceramic body 2 can be in contact and electrically connected, as shown in FIG. Figure 3b As shown. In addition, the ceramic body negative electrode portion 22 on the inner side of the ceramic body 2, which is used to be electrically connected to the core negative electrode portion 12 of the core 1, is configured as a second conductor arranged on the inner side of the ceramic body 2. That is to say, in the case where the core negative electrode portion 12 is constituted by the surface silver layer, and the core positive electrode portion 11 is directly extended from the positive electrode of the laminate, the ceramic body positive electrode portion 21 on the inner side of the ceramic body 2 corresponds to the core positive electrode portion 11 in height. In other words, after the core positive electrode portion 11 extends out of the laminate, it can be directly electrically connected to the ceramic body positive electrode portion 21 that matches it in height without any processing such as bending, thereby further compressing the overall height.

[0073] The positive electrode part 21 and the negative electrode part 22 of the ceramic body are formed of conductive media such as metal and conductive composite materials. This application does not impose any restrictions as long as the electrical connection between the core 1 and the ceramic body 2 can be achieved.

[0074] In one example, the first conductor may be, for example, a metal boss, which may be a metal block with a corresponding height, a hollow metal platform, or an I-shaped metal structure, etc. As long as it has a height corresponding to the core positive electrode portion 11 and has a certain mechanical strength, the present application does not specifically limit its specific shape and structure. Among them, from the perspective of easy processing and structural stability, a metal block is preferred.

[0075] Accordingly, as the second conductor, since the first core negative electrode portion 12 of the corresponding core 1 is a silver layer formed on the surface, the second conductor only needs to be a sheet-shaped conductor attached to the inner side of the ceramic body 2, such as a metal sheet.

[0076] Figure 3a and Figure 3b 1 and 2 show a three-dimensional front view (inside the cavity) and a cross-sectional view of the capacitor according to the first embodiment. Figure 3a As shown, the core positive electrode portion 11 may be in the form of a sheet having a width corresponding to the width of the cavity. In other embodiments, it may be in the form of a strip or a tooth, which is not limited in the present application.

[0077] Next, combine Figures 4 to 6The high temperature resistant capacitor of the second embodiment is further described. In this embodiment, the core 1 is firstly packaged by the insulating layer 16 , and then the packaged core 1 is arranged in the ceramic body 2 .

[0078] Specifically, if Figure 4 As shown, in this embodiment, the core 1 further includes an insulating layer 16 encapsulated outside the laminate, and the core positive electrode portion 11 and the core negative electrode portion 12 respectively pass through the insulating layer 16 from both ends of the laminate and are folded and attached to one surface of the insulating layer 16. In this embodiment, the core 1 is completely covered by the insulating layer 16 (for example, it can be an epoxy resin part, etc.), except for its core positive electrode portion 11 and core negative electrode portion 12, which can further reduce the risk of cracking reaction of the cathode material (conductive polymer) causing the problem of increased ESR.

[0079] Furthermore, if Figure 4 As shown, a positive electrode groove 161 (i.e., corresponding to the first groove) and a negative electrode groove 162 (i.e., corresponding to the second groove) can also be formed on one surface of the insulating layer 16 corresponding to the core positive electrode portion 11 and the core negative electrode portion 12, respectively. The depths of the positive electrode groove 161 and the negative electrode groove 162 match the core positive electrode portion 11 and the core negative electrode portion 12, respectively. That is to say, after the ends of the core positive electrode portion 11 and the core negative electrode portion 12 away from the stack are folded and attached to the positive electrode groove 161 and the negative electrode groove 162, the overall surface of the core 1 is flat. As a result, the installation height can be further reduced when the core 1 is assembled inside the ceramic body 2.

[0080] Correspondingly, if Figure 5 As shown, the ceramic body positive electrode portion 21 and the ceramic body negative electrode portion 22 in the ceramic body 2 are respectively the third conductor and the fourth conductor attached to the inner side of the ceramic body 2. Specifically, the third conductor and the fourth conductor can be metal sheets, or other strip-shaped or tooth-shaped components.

[0081] According to this embodiment, the core 1 is packaged, which can further reduce the risk of cracking of the cathode material and increase the service life. At the same time, by folding the chip positive electrode part 11 and the chip negative electrode part 12 and attaching them in the positive electrode groove 161 and the negative electrode groove 162, no excessive sacrifice is made in height.

[0082] In other words, the first embodiment is more suitable for capacitors used in high temperature, low humidity and narrow spaces, while the second embodiment is more suitable for capacitors used in high temperature, high humidity and less demanding installation spaces. Those skilled in the art can make appropriate choices based on specific usage scenarios.

[0083] The following is a brief introduction to the preparation process of the capacitor of the present application.

[0084] The core 1 in the capacitor of the present application can be prepared by a method for preparing a core 1 for a multilayer capacitor known to those skilled in the art, which will not be described in detail here.

[0085] When preparing the ceramic body 2, firstly, ceramic slurry is prepared, and then the ceramic slurry is formed into a thin sheet by, for example, a casting method, and then a ceramic green body is further stacked around the thin sheet to form a cavity in the middle, thereby obtaining a ceramic green body.

[0086] After that, multiple through holes are respectively opened on the ceramic blank at positions corresponding to the positive electrode pad and the negative electrode pad. In addition, in order to improve the bonding strength between the ceramic body 2 and the cover assembly 1, for example, a tungsten gold layer can be provided at the connection between the ceramic blank and the cover assembly (through sintering, it can better bond with the ceramic to form a transition layer).

[0087] After the holes are opened, the ceramic green body is sintered to obtain a ceramic body.

[0088] Next, solder is applied to the pins of the positive pad and the negative pad, and then the pins are passed through the through holes on the ceramic body so that the pins protrude inside the ceramic body.

[0089] Next, the second positive electrode portion and the second negative electrode portion are connected to the leads of the positive electrode pad and the negative electrode pad, respectively, and welded, thereby obtaining the ceramic body 2 .

[0090] After the core 1 and the ceramic body 2 are prepared separately, they can be assembled as follows:

[0091] First, a nickel layer (for example, it can be set by electroplating) is set at the corresponding position of the connection cover assembly of the ceramic body 2 (for example, the upper edge of the frame of the ceramic body). The nickel layer can better combine with the solder as a second transition layer, thereby improving the overall bonding strength.

[0092] Thereafter, a valve ring (which may be an iron-cobalt-nickel alloy, for example) may be soldered onto the nickel layer by soldering.

[0093] The SEM image of the welding position of the ceramic body 2 prepared as above is as follows: Figure 7 As shown, after atomic detection, a represents alumina ceramic, b shows the tungsten gold layer, c shows the nickel layer, d shows the Ag / Cu solder used, and e is the iron-cobalt-nickel alloy layer of the valve ring.

[0094] Thereafter, the core 1 is disposed within the ceramic body 2, and the cap assembly 3 is further welded to the valve ring, thereby forming a hermetically sealed capacitor.

[0095] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A high temperature resistant capacitor, characterized in that: include: a core including a first positive electrode portion and a first negative electrode portion; and A sealing assembly, the sealing assembly comprising a ceramic body and a cover assembly, the ceramic body having an opening, the cover assembly covering the opening of the ceramic body and defining a cavity between the cover assembly and the ceramic body, Wherein, the core is arranged in the cavity, A second positive electrode part and a second negative electrode part are respectively provided on the inner side of the ceramic body, and a positive electrode pad and a negative electrode pad are respectively provided on an outer surface of the ceramic body, a pin of the positive electrode pad passes through the ceramic body and is electrically connected to the second positive electrode part, a pin of the negative electrode pad passes through the ceramic body and is electrically connected to the second negative electrode part, the second positive electrode part is electrically connected to the first positive electrode part and the second negative electrode part is electrically connected to the first negative electrode part, and the cavity as a whole is in an airtight state.

2. The high temperature resistant capacitor according to claim 1, characterized in that: The cover component is a ceramic part or a metal part.

3. The high temperature resistant capacitor according to claim 1, characterized in that: The core also includes a laminate, which includes a plurality of laminated sheets, each of which includes a substrate, one end of which is a positive electrode and the other end of which is a negative electrode, a silver layer is provided on the upper and lower surfaces of the negative electrode of the sheet, and a shielding layer is provided on the upper and lower surfaces of the positive electrode of the sheet and adjacent to the silver layer.

4. The high temperature resistant capacitor according to claim 3, characterized in that: The plurality of single-piece positive electrodes are connected in parallel and electrically connected to the first positive electrode portion, the first positive electrode portion extends from the stacked body, and the silver layer on one surface of the stacked body constitutes the first negative electrode portion.

5. The high temperature resistant capacitor according to claim 4, characterized in that: The second positive electrode portion is a first conductor disposed inside the ceramic body, and the height and position of the first conductor correspond to the first positive electrode portion. The second negative electrode portion is a second conductor disposed inside the ceramic body.

6. The high temperature resistant capacitor according to claim 5, characterized in that: The first conductor is a metal boss, and the second conductor is a metal sheet.

7. The high temperature resistant capacitor according to claim 3, characterized in that: The core further includes an insulating layer encapsulated outside the stack, and the first positive electrode portion and the first negative electrode portion respectively pass through the insulating layer from both ends of the stack and are folded and attached to one surface of the insulating layer.

8. The high temperature resistant capacitor according to claim 7, characterized in that: A first groove and a second groove are formed on a surface of the insulating layer corresponding to the first positive electrode part and the first negative electrode part, respectively. The depths of the first groove and the second groove match the first positive electrode part and the first negative electrode part, respectively. The ends of the first positive electrode part and the first negative electrode part away from the stack are respectively arranged in the first groove and the second groove.

9. The high temperature resistant capacitor according to claim 7, characterized in that: The second positive electrode portion and the second negative electrode portion are respectively a third conductor and a fourth conductor attached to the inner surface of the ceramic body.

10. The high temperature resistant capacitor according to claim 9, characterized in that: The third conductor and the fourth conductor are metal sheets respectively.

11. The high temperature resistant capacitor according to claim 1, characterized in that: Through holes are formed on the ceramic body corresponding to the positive electrode pad and the negative electrode pad, respectively. The pin of the positive electrode pad is connected to the second positive electrode part through the through hole, and the pin of the negative electrode pad is connected to the second negative electrode part through the through hole, and the through hole and the pin are sealed by solder.

12. The high temperature resistant capacitor according to claim 1, characterized in that: A valveable ring is welded to the upper edge of the ceramic body, and the ceramic body is connected to the cover assembly via the valveable ring.

13. The high temperature resistant capacitor according to claim 12, characterized in that: A tungsten gold layer and a nickel layer are sequentially stacked between the upper edge of the ceramic body and the valve ring from the ceramic body upward.

14. The high temperature resistant capacitor according to claim 1, characterized in that: The material of the ceramic body is alumina.

15. The high temperature resistant capacitor according to claim 1, characterized in that: A hydrophobic layer is arranged on the surface of the ceramic body.

16. The high temperature resistant capacitor according to claim 1, characterized in that: The overall height of the high temperature resistant capacitor is less than 2.5 mm.

17. The high temperature resistant capacitor according to claim 1, characterized in that: The high temperature resistant capacitor is any one of a laminated aluminum electrolytic capacitor, a cylindrical aluminum electrolytic capacitor, and a tantalum capacitor.

Images