High-temperature-resistant capacitor

Abstract

Provided in the present application is a high-temperature-resistant capacitor, comprising: a core, which comprises a first positive electrode portion and a first negative electrode portion; and a sealing assembly, which comprises a ceramic body and a cover assembly, wherein the ceramic body is provided with an opening; the cover assembly covers the opening of the ceramic body, and a cavity is defined between the cover assembly and the ceramic body; the core is arranged in the cavity; a second positive electrode portion and a second negative electrode portion are provided on an inner side of the ceramic body, and a positive bonding pad and a negative bonding pad are provided on an outer surface of the ceramic body; a pin of the positive bonding pad penetrates the ceramic body and is electrically connected to the second positive electrode portion; a pin of the negative bonding pad penetrates the ceramic body and is electrically connected to the second negative electrode portion; the second positive electrode portion is electrically connected to the first positive electrode portion, and the second negative electrode portion is electrically connected to the first negative electrode portion; and the cavity as a whole is in an airtight state. Compared with a capacitor using a sealing assembly fully made of metal, the overall height of the high-temperature-resistant capacitor according to the present application can be further reduced.

Description

High temperature resistant capacitors

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on August 15, 2023, with application number 202311036887.5 and application name “High Temperature Resistant Capacitor”. The entire contents of the above application are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the technical field of capacitors, and more particularly to a high-temperature resistant capacitor. Background Art

[0003] With the rapid development of science and technology in recent years, electronic products are rapidly developing towards thinner, lighter, and surface-mount designs. With the development of high-density designs, the demand for capacitor capacity continues to increase, and the temperature of product boards continues to rise.

[0004] Traditional plastic-encapsulated chip-type multilayer aluminum electrolytic capacitors (SP-CAP) can meet high specific capacitance requirements. However, the external encapsulation material of traditional SP-CAP capacitors is epoxy resin, which has poor high temperature resistance and a non-airtight structure. Air can continuously 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 function and cause device failure. For this reason, plastic-encapsulated chip-type multilayer aluminum electrolytic capacitors are prohibited from use in high temperature scenarios.

[0005] Therefore, there is an urgent need to provide a high-temperature resistant capacitor that can meet the increasing miniaturization requirements of current electronic devices.

[0006] Summary of the Invention

[0007] 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.

[0008] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0009] A high temperature resistant capacitor according to an embodiment of the present application includes:

[0010] a core, the core comprising a first positive electrode portion and a first negative electrode portion;

[0011] A sealing assembly comprising a ceramic body and a cover assembly, wherein the ceramic body has an opening, the cover assembly covers the opening of the ceramic body and defines a cavity between the cover assembly and the ceramic body,

[0012] In which, the core is arranged in the cavity, and the inner side of the ceramic body is respectively provided with a second positive electrode part and a second negative electrode part, 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.

[0013] 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.

[0014] It should be noted that the phrase "the entire cavity is in an airtight state" means that the ceramic body and the cover assembly are airtightly packaged, and the positive and negative electrode pads, while passing through the ceramic body, are not airtightly packaged with the ceramic body. This allows the sealing assembly to provide airtight protection for the core disposed therein, preventing gas from entering the interior and causing cracking reactions in the cathode material of the core. In other words, the high-temperature resistant capacitor of the present application, by adopting a high-temperature resistant sealing assembly, not only achieves high temperature resistance, but also, because the entire cavity is in an airtight state, can withstand harsh operating environments such as high humidity.

[0015] According to some embodiments of the present application, the cover assembly is a ceramic part or a metal part.

[0016] In other words, the entire sealing assembly can be made entirely of ceramic, or a combination of a ceramic body and a metal cover, and the specific choice can be made based on the space requirements of the application scenario.

[0017] According to some embodiments of the present application, the core also includes a laminate, which includes a plurality of stacked single sheets, each of which includes a substrate, one end of the substrate is a positive electrode and the other end is 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.

[0018] In other words, the high-temperature resistant capacitor of the present application can be applied to a multilayer capacitor. In a multilayer capacitor, the core adopts a laminate structure, and each single piece in the laminate 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.

[0019] 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 one surface of the stack constitutes the first negative electrode portion.

[0020] That is, for the multilayer capacitor, the core does not need to be provided with a separate first negative electrode portion for electrical connection to the sealing assembly, and electrical connection can be achieved directly through the silver layer provided on the surface of the stacked body, thereby further achieving miniaturization.

[0021] 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.

[0022] That is to say, when the first negative electrode portion is composed of 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.

[0023] Furthermore, the first conductor is a metal boss, and the second conductor is a metal sheet.

[0024] 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.

[0025] According to 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.

[0026] In other words, in addition to directly placing the core within the ceramic body, the core can also be encapsulated and then placed within 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 overall volume of the core to meet the requirements of miniaturization, 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.

[0027] Furthermore, a first groove and a second groove are formed on a surface of the insulating layer corresponding to the first positive electrode portion and the first negative electrode portion, respectively, and the depths of the first groove and the second groove match the first positive electrode portion and the first negative electrode portion, respectively, 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.

[0028] That is to say, after the core is packaged, although the first positive electrode portion and the first negative electrode portion are attached to the surface of the insulating layer, the overall height of the core does not need to be increased by correspondingly providing the first groove and the second groove on the insulating layer.

[0029] 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.

[0030] Furthermore, the third conductor and the fourth conductor are metal sheets respectively. That is, 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 portion and second negative electrode portion.

[0031] 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. 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 during 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.

[0032] According to some embodiments of the present application, a valve ring is welded to the upper edge of the ceramic body, and the ceramic body is connected to the cover assembly through the valve ring.

[0033] By providing a valve ring and then connecting the cover assembly via the valve ring, an airtight connection can be achieved between the ceramic body and the cover assembly, and the process is relatively simple.

[0034] 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.

[0035] 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 them, alumina ceramics are preferred due to its advantages such as low raw material cost and low sintering temperature.

[0036] According to some embodiments of the present application, a hydrophobic layer is provided on the surface of the ceramic body, thereby further improving the high humidity resistance of the capacitor.

[0037] According to some embodiments of the present application, the overall height of the high-temperature resistant capacitor is less than 2.5 mm. The high-temperature resistant capacitor of the present application can be controlled to have an overall height of less than 2.5 mm, which is far superior to the multilayer capacitors currently on the market and can further meet the requirements of miniaturization and thinning of electronic products. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] FIG1 is a schematic structural diagram of a core of a high-temperature resistant capacitor according to an embodiment of the present invention;

[0039] FIG2 is a 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;

[0040] FIG3 a is a schematic diagram of a partial three-dimensional structure of a high-temperature resistant capacitor according to an embodiment of the present invention;

[0041] FIG3 b is a schematic side cross-sectional view of a high temperature resistant capacitor according to an embodiment of the present invention;

[0042] FIG4 is a schematic structural diagram 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;

[0043] FIG5 is a schematic structural diagram 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;

[0044] FIG6 is a schematic structural diagram of a high temperature resistant capacitor according to another embodiment of the present invention;

[0045] 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;

[0046] FIG8 is a schematic diagram of a core structure according to an embodiment;

[0047] FIG. 9 is a schematic structural diagram of a fully metal-packaged capacitor according to another embodiment. DETAILED DESCRIPTION

[0048] To make the purpose, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.

[0049] The high-temperature resistant capacitor (hereinafter referred to as the capacitor) of the present application includes a core and a sealing assembly. The sealing assembly includes a ceramic body and a cover assembly, wherein the cover assembly covers an opening of the ceramic body, thereby defining a cavity structure within the sealing assembly. The core is disposed within the cavity, and the electrodes of the core are electrically connected to the outside world via electrodes provided on the ceramic body. The cavity of the sealing assembly is in an airtight state as a whole.

[0050] Figure 8 shows a laminated aluminum capacitor. As shown in Figure 8, an epoxy resin insulation layer 16 is encapsulated on the outside of the core 1. This capacitor needs to be further improved in terms of high temperature resistance and further reduced in height / size.

[0051] Some implementations have proposed modifying epoxy resin materials to form the capacitor casing, and improving the bonding between the resin material and the positive and negative lead frames to enhance high-temperature resistance. However, even with this approach, the capacitor can only meet the 10-year lifespan requirement below 75°C, and cannot meet the 10-year lifespan requirement above 75°C.

[0052] Referring to Figure 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 packaging, which limits the reduction of its overall height. In addition, in order to avoid short circuits caused by direct contact between the core and the metal base plate, an insulating gasket 300 must be provided between the metal base plate and the core for all-metal packaging, which further limits the compression space of the capacitor in height.

[0053] The capacitor provided in accordance with the embodiments of the present application utilizes a ceramic body 2, utilizing its high temperature resistance, insulation, and inherent mechanical properties. This allows for improved high temperature resistance compared to epoxy resin capacitors, while also allowing for greater height compression compared to metal body capacitors. Furthermore, the hermetic sealing between the ceramic body and a cover assembly (e.g., a metal plate or ceramic plate) addresses the issue of increased ESR, which can be caused by decreased conductivity of the polymer material in the core in a hot oxygen environment.

[0054] Below, taking a multilayer capacitor as an example, a high-temperature resistant capacitor (hereinafter sometimes referred to as a capacitor) according to the present application is described in detail with reference to the accompanying drawings. Figures 1 to 3 show schematic diagrams of the structure of a high-temperature resistant capacitor of a first embodiment, including its core 1 and a ceramic body 2, one of the sealing components. Figures 4 to 6 show schematic diagrams of the structure of a high-temperature resistant capacitor of a second embodiment, including its core 1 and a ceramic body 2, one of the sealing components.

[0055] The high-temperature resistant capacitor according to the present application can be, for example, any one of a laminated aluminum electrolytic capacitor, a cylindrical aluminum electrolytic capacitor, and a tantalum capacitor. In other words, the high-temperature resistant capacitor according to the present application is not only applicable to laminated aluminum electrolytic capacitors, but can also be extended to cylindrical aluminum electrolytic capacitors and tantalum capacitors, thus having a wide range of applications.

[0056] The following first describes the substantially identical features of the two embodiments with reference to the accompanying drawings.

[0057] As shown in Figures 3 and 6, 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, defining a cavity between the cover assembly 3 and the ceramic body 2, and the core 1 is disposed in the cavity.

[0058] As shown in FIG. 1 and FIG. 4 , 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).

[0059] According to some embodiments of the present application, taking a laminated aluminum electrolytic capacitor as an example, as shown in Figures 1 and 4, the core 1 can be formed by growing a polymer material on one end (i.e., close to the negative electrode) of an aluminum foil (i.e., a substrate), and then impregnating carbon on the polymer and growing a silver material to form a silver layer 13. Thereafter, an insulating layer is provided at the end 15 of the silver material close to the positive electrode as a shielding layer 14 to isolate the positive and negative electrodes, thereby forming a single piece. Then, multiple single pieces are stacked to form a laminate. As the electrode of the core 1, for example, it can be a metal conductor such as a copper sheet drawn out from the laminate.

[0060] As shown in FIG2(b) and FIG5(b), 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 provided on the inner side of the ceramic body 2, respectively. A positive electrode pad 23 and a negative electrode pad 24 are provided on an outer surface of the ceramic body 2, respectively. 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 pole of the core 1 is electrically connected to the positive pole pad 23 located on the outside of the ceramic body 2 through the core positive pole part 11 and the ceramic body positive pole part 21, and the negative pole of the core 1 is electrically connected to the negative pole pad 24 located on the outside of the ceramic body 2 through the core negative pole part 12 and the ceramic body negative pole part 22.

[0061] In capacitor design, while through-holes are required in the ceramic body 2 to ensure electrical connection between the external solder pads and the internal positive and negative electrodes, the overall cavity must remain airtight. In other words, the ceramic body 2 with the solder pads must meet airtight requirements. When mated with the cap assembly, the ceramic body forms an airtight cavity.

[0062] According to some embodiments of the present application, through holes (not shown) are formed on the ceramic body 2 corresponding to the positive electrode pad 23 and the negative electrode pad 24, respectively. 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.

[0063] 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.

[0064] 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 to the sealing assembly made of all metal, since the ceramic body 2 itself is insulating, there is no need to set an insulating gasket between the ceramic body 2 and the core 1, thereby further reducing the overall height. In addition, the ceramic body 2 itself has a certain mechanical strength and rigidity. Compared to ductile metal, it can be made thinner, thereby further reducing the overall height. Moreover, compared to the sealing assembly made of all metal, the processing technology of the electrical connection between the ceramic body 2 and the core 1 becomes simpler and easier to operate.

[0065] As shown in Figures 3 and 6, the cover assembly 3 that cooperates 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 ceramic, or a combination of a ceramic body and a metal cover. The specific selection can be made according to the installation space conditions of the application scenario.

[0066] For example, multiple through holes may be provided for the positive electrode pad 23 and the negative electrode pad 24. 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.

[0067] In some embodiments, as shown in FIG2 , 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 .

[0068] Furthermore, as shown in FIG7 , 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. Furthermore, the tungsten-gold layer and the nickel layer can also be well bonded. Thus, with the tungsten-gold layer and the nickel layer acting as transition layers, the valve ring can be firmly bonded to the ceramic body.

[0069] The material of the ceramic body 2 can be, for example, alumina. Common ceramics such as alumina ceramics, zirconia ceramics, and silicon carbide ceramics can be used as the material of the ceramic body. Alumina ceramics are preferred due to their low raw material cost and low sintering temperature.

[0070] 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.

[0071] 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.

[0072] Hereinafter, the implementation details of the high temperature resistant capacitor of the first embodiment will be further described with reference to FIG. 1 to FIG. 3 .

[0073] As shown in Figures 1 to 3, in this embodiment, multiple single-piece positive electrodes are connected in parallel and electrically connected to the metal conductor extending from the stack to form the core positive electrode portion 11 of the core; the silver layer on the surface of the stack can be directly used to form the core negative electrode portion 12 of the core, without the need for a separate extending or other form of negative electrode.

[0074] Accordingly, as shown in FIG2 , in this embodiment, the ceramic body positive electrode portion 21 on the inner side of the ceramic body 2, which is used to electrically connect to the core positive electrode portion 11 of the core 1, is configured as a first conductor disposed on the inner side of the ceramic body 2. 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 can contact and electrically connect to the first conductor on the inner side of the ceramic body 2, as shown in FIG3 b. In addition, the ceramic body negative electrode portion 22 on the inner side of the ceramic body 2, which is used to electrically connect to the core negative electrode portion 12 of the core 1, is configured as a second conductor disposed on the inner side of the ceramic body 2. That is to say, when the core negative electrode part 12 is composed of a surface silver layer and the core positive electrode part 11 is directly extended from the positive electrode of the stack, the ceramic body positive electrode part 21 on the inner side of the ceramic body 2 corresponds to the core positive electrode part 11 in height. In other words, after the core positive electrode part 11 extends out of the stack, it can be directly electrically connected to the ceramic body positive electrode part 21 that matches it in height without any bending or other processing, thereby further compressing the overall height.

[0075] Among them, the positive electrode part 21 of the ceramic body and the negative electrode part 22 of the ceramic body are formed by conductive media such as metal, conductive composite materials, etc. 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.

[0076] In one example, the first conductive member can be a metal boss. This metal boss can be a metal block of a corresponding height, a hollow metal platform, or an I-shaped metal structure. As long as it has a height corresponding to the core positive electrode portion 11 and has a certain mechanical strength, this application does not impose any specific restrictions on its specific shape or structure. From the perspectives of ease of processing and structural stability, a metal block is preferred.

[0077] 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.

[0078] Figures 3a and 3b respectively illustrate a three-dimensional front view (within the cavity) and a cross-sectional view of the capacitor according to the first embodiment. As shown in Figure 3a, the core positive electrode portion 11 can be in the form of a sheet with a width corresponding to the cavity width. In other embodiments, it can be in the form of a strip or tooth, which is not limited in this application.

[0079] The second embodiment of the high temperature resistant capacitor is further described below with reference to Figures 4 to 6. In this embodiment, the core 1 is first encapsulated by the insulating layer 16, and then the encapsulated core 1 is placed in the ceramic body 2.

[0080] Specifically, as shown in FIG4 , in this embodiment, the core 1 further includes an insulating layer 16 encapsulated outside the laminate. The core positive electrode portion 11 and the core negative electrode portion 12 respectively pass through the insulating layer 16 from opposite ends of the laminate and are folded and attached to one surface of the insulating layer 16. In this embodiment, the core 1, except for its core positive electrode portion 11 and core negative electrode portion 12, is completely covered by the insulating layer 16 (e.g., an epoxy resin member). This can further reduce the risk of cracking reactions of the cathode material (conductive polymer) and the resulting increase in ESR.

[0081] Furthermore, as shown in FIG4 , 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 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, after the ends of the core positive electrode portion 11 and the core negative electrode portion 12 away from the laminate 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.

[0082] Correspondingly, as shown in FIG5 , the ceramic body positive electrode portion 21 and the ceramic body negative electrode portion 22 in the ceramic body 2 are respectively the third and fourth conductors attached to the inner side of the ceramic body 2. Specifically, the third and fourth conductors can be metal sheets, or other components in the shape of strips or teeth.

[0083] According to this embodiment, the core 1 is packaged, which can further reduce the risk of cracking of the cathode material and improve 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 to the positive electrode groove 161 and the negative electrode groove 162, no excessive sacrifice is made in height.

[0084] In other words, the first embodiment is more suitable for capacitors used in high-temperature, low-humidity, and more confined spaces, while the second embodiment is more suitable for capacitors used in less demanding installation spaces with high temperatures, high humidity, and high humidity. Those skilled in the art can make the appropriate choice based on the specific usage scenario.

[0085] The following is a brief introduction to the preparation process of the capacitor of this application.

[0086] 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.

[0087] 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 tape casting method, and then ceramic green bodies are further stacked around the thin sheet to form a cavity in the middle, thereby obtaining a ceramic green body.

[0088] Afterwards, multiple through holes are opened on the ceramic body 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 body and the cover assembly (which can better bond with the ceramic through sintering to form a transition layer).

[0089] After the holes are opened, the ceramic green body is sintered to obtain a porcelain body.

[0090] Next, apply solder to the pins of the positive pad and the negative pad, and then pass the pins through the through holes on the porcelain body so that the pins protrude inside the porcelain body.

[0091] 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 together, thereby obtaining the ceramic body 2 .

[0092] After the core 1 and the ceramic body 2 are prepared separately, they can be assembled as follows:

[0093] 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 bond with the solder as a second transition layer, thereby improving the overall bonding strength.

[0094] Thereafter, a valve ring (which may be an iron-cobalt-nickel alloy, for example) may be soldered onto the nickel layer by soldering.

[0095] The SEM image of the welding position of the ceramic body 2 prepared as described above is shown in Figure 7. 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.

[0096] 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.

[0097] 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 within 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.

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