High-capacity aluminum electrolytic capacitor with high reliability

Abstract

The utility model discloses a high-reliability high-capacity aluminum electrolytic capacitor, and particularly relates to the technical field of aluminum electrolytic capacitors, which comprises an aluminum electrolytic capacitor main body, the aluminum electrolytic capacitor main body comprises an aluminum shell, and a core bag is arranged in the aluminum shell. The core cladding sequentially comprises a first electrolyte, a cathode foil, a second electrolyte and an anode foil from outside to inside, and the thickness of the cathode foil is 50 microns. According to the utility model, the cathode foil with the thickness of 50 microns and voltage resistance is adopted, and after working, the cathode foil has higher specific volume compared with the traditional cathode foil with the thickness of 20 microns, so that the capacity attenuation amplitude is obviously reduced in the working process, the stability and the reliability of the capacitor in long-time operation are ensured, meanwhile, the heating condition of the capacitor is effectively improved, and the service life of the capacitor is prolonged. And secondly, from the aspect of resistance performance, the RC resistance of the 50 [mu] m cathode foil is smaller, the heat generated when the current passes through is further reduced, and a good heat dissipation cycle is formed.

Description

TECHNICAL FIELD

[0001] The utility model relates to aluminum electrolytic capacitor technical field, concretely relates to a high reliability's large capacity aluminum electrolytic capacitor. BACKGROUND

[0002] Aluminum electrolytic capacitor mainly comprises anode aluminum foil, cathode aluminum foil, electrolytic paper, electrolyte and shell, the surface of anode aluminum foil forms an extremely thin alumina dielectric film through electrochemical method, the film is the key factor to determine the voltage resistance performance of the capacitor, the cathode aluminum foil is usually light foil or etched foil, which together with the electrolyte forms the cathode, the electrolytic paper is located between the anode foil and the cathode foil, and plays the role of isolation and adsorption of electrolyte, to ensure that electrons can conduct through the electrolyte between the two poles, thereby realizing the energy storage function of the capacitor;

[0003] At present, the cathode foil with a thickness of 20 microns is commonly used in aluminum electrolytic capacitors, and the contact area with the shell or heat dissipation component is relatively limited, the heat conduction path is relatively narrow, which makes it difficult to quickly and effectively dissipate heat, easily leading to an increase in the internal temperature of the capacitor, and further affecting the performance stability of the capacitor, accelerating the aging process of the capacitor, and shortening its service life, and the thin 20 microns cathode foil usually has a large equivalent series resistance, which will generate more heat when current passes through, not only aggravating the heat dissipation problem, but also causing a series of chain reactions such as accelerated evaporation of electrolyte and accelerated corrosion of electrode material due to the additional heat generated, secondly, in the application number 202322177131.4, an aluminum electrolytic capacitor is disclosed, which comprises an aluminum shell, a sealing rubber cover, a plastic sleeve film, a tab, a support ring, a positioning rod, a positioning ring, an insulating ring, a substrate, a connecting column and a protective cover, the aluminum shell is provided with a sealing rubber cover at one end, and the aluminum shell and the sealing rubber cover are provided with a plastic sleeve film outside, the above only relies on the sealing rubber cover as the only sealing layer, and the single sealing rubber cover is difficult to maintain the sealing performance for a long time, once the rubber cover is aged, damaged or not tightly sealed, the electrolyte will leak out from the joint of the sealing rubber cover and the aluminum shell, resulting in a decrease in the capacitance of the capacitor, and the moisture, dust and impurities in the external environment are easy to enter the internal part of the aluminum shell, thereby affecting the performance and service life of the capacitor, and even possibly causing short circuit, failure and other faults of the capacitor. SUMMARY

[0004] The utility model aims at providing a high reliability's large capacity aluminum electrolytic capacitor to solve the above-mentioned shortcomings in the prior art.

[0005] In order to achieve the above object, the utility model provides the following technical scheme: A high reliability's large capacity aluminum electrolytic capacitor, including aluminum electrolytic capacitor main part, the aluminum electrolytic capacitor main part includes aluminum shell, the inside of aluminum shell is equipped with core package, the core package includes first electrolyte, cathode foil, second electrolyte and anode foil gradually from outside to inside, the thickness of cathode foil is 50um, and the upper end of core package is equipped with aluminum pad lead-out piece, one end of aluminum pad lead-out piece is connected with lead, the upper end surface opening of aluminum shell is equipped with cover plate, the lower end surface of cover plate is fixedly connected with rubber plug.

[0006] Through the above technical scheme:

[0007] Adopt the thickness of 50um the cathode foil, and the cathode foil has voltage resistance, first, from the performance stability angle, the specific capacity is higher, in the capacitor working process, its capacity attenuation degree is smaller, guarantees that the capacitor maintains the stable capacitance performance under long time operation, avoids the adverse effect of the large fluctuation of capacitance value to the circuit, second, in the heat generation characteristic, the equivalent series resistance is smaller, according to Joule's law, the heat generated when the current passes through is proportional to resistance, can effectively reduce the heat generated when the capacitor works, thereby avoiding the capacitor performance degradation or even damage caused by overheating, prolongs the service life of the capacitor, enhances its reliability and durability in various complex circuit environments.

[0008] Preferably, the outer portion of the cover plate is sleeved with a sealing sleeve, the outer portion of the sealing sleeve and the inner surface wall of the aluminum shell are connected with a sealing ring, the outer surface wall of the sealing sleeve is fixedly connected with a first tooth ring block, and the inner surface wall of the sealing ring is provided with a first embedding groove matched with the first tooth ring block.

[0009] Preferably, the outer surface wall of the rubber plug is fixedly connected with a second tooth ring block, and the inner surface wall of the aluminum shell is provided with a second embedding groove matched with the second tooth ring block.

[0010] Specifically, through the cooperation of the second tooth ring block and the second embedding groove, the sealing tightness between the rubber plug and the aluminum shell is enhanced, the key components such as electrolyte and electrode inside the capacitor can be better protected, and the stability of the internal environment of the capacitor is maintained, and secondly, when the capacitor is affected by external factors such as vibration, impact or temperature change, the rubber plug will not easily displace or loosen, ensuring the integrity and reliability of the sealing structure.

[0011] Through the above technical scheme:

[0012] In use, the sealing sleeve outside the cover plate is embedded in the inside of the sealing ring, the first tooth ring block of the outer surface wall of the sealing sleeve is embedded in the first embedding groove of the inner surface wall of the sealing ring, which can provide additional sealing effect for the aluminum electrolytic capacitor, combined with the sealing of the rubber plug, forming double insurance, ensuring the stability of the capacitor, avoiding the disadvantages of single rubber plug sealing, which may cause loosening or displacement and affect the sealing effect, the additional sealing can share the external force to a certain extent, ensuring the stability of the overall sealing, ensuring that the internal environment of the capacitor is not disturbed by external factors, maintaining the stability of the capacitor performance.

[0013] Preferably, the aluminum electrolytic capacitor body is provided with a pressure balance structure, the pressure balance structure is arranged on the upper end face of the cover plate, a through groove is arranged at the lower end of the placement groove and above the upper end face of the rubber plug, and a fixing ring is arranged in the placement groove.

[0014] Preferably, the pressure balance membrane comprises a protective layer, a gas selective permeation layer and a base layer, the gas selective permeation layer is arranged between the protective layer and the base layer, the protective layer is made of polyamide material, has good wear resistance and chemical resistance, can protect the internal gas selective permeation layer from damage by external environment, the gas selective permeation layer is a microporous membrane made of polytetrafluoroethylene, has excellent chemical stability and hydrophobicity, can effectively filter out liquid components and only allow gas molecules to enter and exit, and the base layer is made of polyethylene terephthalate material, has high tensile strength and good dimensional stability, provides basic physical strength for the entire pressure balance membrane, and prevents the membrane from being easily broken during use.

[0015] Preferably, the outer surface wall of the fixing ring is fixedly connected with a sealing ring, the sealing ring is fixedly connected to the inner surface wall of the placement groove, the upper end face of the placement groove is fixedly connected with an upper ring block, the lower end face of the upper ring block is fixedly connected with a top pressing block, the lower end face of the top pressing block is in contact with the upper end face of the sealing ring, the sealing ring can effectively fill the possible small gap between the placement groove and the fixing ring, prevent external liquid, gas and other impurities from entering the inside of the aluminum electrolytic capacitor body, and ensure the stability of the internal environment of the aluminum electrolytic capacitor, and the upper ring block and the top pressing block fix and compact the sealing ring, so that the sealing ring will not be displaced or deformed due to factors such as vibration and temperature change during long-term use, thereby maintaining good sealing effect.

[0016] Specifically, when there is a difference between the internal pressure and the external pressure of the aluminum electrolytic capacitor body, gas molecules will enter the placing groove through the through groove according to the pressure difference, flow through the pressure balance film, if the internal pressure is high, the gas will flow from the inside to the outside through the pressure balance film, if the internal pressure is low, the gas will flow from the outside to the inside through the pressure balance film, so as to balance the internal and external pressures, prevent the sealing failure or the shell deformation caused by the too large pressure difference, ensure the relatively stable internal pressure of the capacitor, keep the relative stability of the electrode spacing and the electrolyte distribution, reduce the electrical performance changes caused by the pressure fluctuation, make the capacitor work reliably in the circuit, and effectively reduce the probability of the capacitor performance failure caused by the pressure imbalance.

[0017] In the above technical solution, the technical effects and advantages provided by the utility model are as follows:

[0018] 1、The aluminum electrolytic capacitor adopts a 50 mu m thick and pressure-resistant cathode foil, after working, compared with the traditional 20 mu m negative pole foil, has higher specific capacity, so that the capacity attenuation amplitude in the working process is significantly reduced, thereby ensuring the stability and reliability of the capacitor under long-time operation, at the same time, the heat generation is also effectively improved, avoiding the risk of thermal influence on surrounding electronic elements caused by overheating, secondly, from the resistance performance, the RC resistance of the 50 mu m negative pole foil is smaller, further reducing the heat generated when the current passes, forming a good heat dissipation circulation, finally, the 50 mu m negative pole foil has a larger contact area with the bottom aluminum shell due to the larger thickness, more effectively conducting the temperature in the core package center to the external environment, fast heat dissipation and strong impact resistance.

[0019] 2、By setting the sealing sleeve, the sealing ring, the first tooth ring block and the first embedding groove, additional sealing effect can be provided for the aluminum electrolytic capacitor, double insurance is formed in combination with the rubber plug sealing, effectively preventing the moisture, dust and impurities in the external environment from entering the capacitor, and when the capacitor is subjected to external vibration, impact or temperature change, etc., the disadvantages of loose or displacement caused by single rubber plug sealing are avoided, the stability of the overall sealing is ensured, the internal environment of the capacitor is ensured not to be disturbed by external factors, the stability of the capacitor performance is maintained, in addition, through the pressure balance structure, when there is a difference between the internal pressure and the external pressure of the capacitor, gas molecules can flow according to the pressure difference, so that the internal pressure can be balanced with the external pressure in time, the risk of damage of the above structure is effectively avoided, the integrity of the physical structure of the capacitor is ensured, and the internal pressure can also be maintained within a reasonable range, reducing the possibility of electrolyte leakage. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments described in the present application, and other drawings can also be obtained by those skilled in the art according to these drawings.

[0021] Figure 1 It is a schematic diagram of the overall structure of the present application.

[0022] Figure 2 It is a schematic diagram of the plane section of the present application.

[0023] Figure 3 It is a schematic diagram of the core package structure of the present application.

[0024] Figure 4 It is a schematic diagram of the shell section of the present application.

[0025] Figure 5 It is an enlarged schematic diagram of the connection between the top cover and the shell of the present application.

[0026] Figure 6 It is a schematic diagram of the top cover section of the present application.

[0027] Figure 7 It is an enlarged schematic diagram of the pressure balance structure of the present application.

[0028] Figure 8 It is a schematic diagram of the pressure balance membrane structure of the present application.

[0029] Explanation of reference signs:

[0030] 1, aluminum electrolytic capacitor body; 11, aluminum shell; 12, core package; 121, first electrolyte; 122, cathode foil; 123, second electrolyte; 124, anode foil; 13, aluminum pad lead-out sheet; 14, lead wire; 15, cover plate; 16, rubber plug; 2, sealing sleeve; 3, sealing ring; 4, first tooth ring block; 5, first embedding groove; 6, second tooth ring block; 7, second embedding groove; 8, pressure balance structure; 81, placing groove; 82, through groove; 83, fixing ring; 84, pressure balance membrane; 841, protective layer; 842, gas-selective permeation layer; 843, base layer; 85, sealing ring; 86, top pressing block; 87, upper ring block. DETAILED DESCRIPTION

[0031] In order to make those skilled in the art better understand the technical solutions of the present application, the present application will be further described in detail with reference to the drawings.

[0032] The present application provides a high-reliability large-capacity aluminum electrolytic capacitor as shown in Figures 1-4 the drawings.

[0033] The aluminum electrolytic capacitor body 1 comprises an aluminum shell 11, the inside of the aluminum shell 11 is provided with a core package 12, the core package 12 comprises a first electrolyte 121, a cathode foil 122, a second electrolyte 123 and an anode foil 124 from outside to inside, the thickness of the cathode foil 122 is 50 mu m, and the upper end of the core package 12 is provided with an aluminum pad lead-out sheet 13, one end of the aluminum pad lead-out sheet 13 is connected with a lead wire 14, and the upper end surface opening of the aluminum shell 11 is provided with a cover plate 15, and the lower end surface of the cover plate 15 is fixedly connected with a rubber plug 16.

[0034] Through the above technical scheme:

[0035] The cathode foil 122 with a thickness of 50 mu m has voltage resistance. Firstly, from the perspective of performance stability, the specific capacity is higher, and the capacity attenuation degree is smaller during the operation of the capacitor, so that the capacitor can maintain stable capacitance performance for a long time, and the adverse effects of large fluctuations of the capacitance value on the circuit are avoided. Secondly, in terms of heat generation characteristics, the equivalent series resistance is small. According to Joule's law, the heat generated when current passes through is proportional to the resistance, so that the heat generated during the operation of the capacitor can be effectively reduced, thereby avoiding the performance degradation or even damage of the capacitor due to overheating, prolonging the service life of the capacitor and enhancing the reliability and durability of the capacitor in various complex circuit environments.

[0036] The utility model provides a kind of high reliability's large capacity aluminum electrolytic capacitor as Figures 3-6 As shown in the figure, the outer part of cover plate 15 is provided with sealing sleeve 2, the outer part of sealing sleeve 2 and the inner surface wall of aluminum shell 11 are connected with sealing ring 3, the outer surface wall of sealing sleeve 2 is fixedly connected with first tooth ring block 4, and the inner surface wall of sealing ring 3 is provided with first embedding groove 5 matched with first tooth ring block 4.

[0037] Further, as shown in Figure 5 The outer surface wall of rubber plug 16 is fixedly connected with second tooth ring block 6, and the inner surface wall of aluminum shell 11 is provided with second embedding groove 7 matched with second tooth ring block 6.

[0038] Specifically, through the cooperation of second tooth ring block 6 and second embedding groove 7, the sealing tightness between rubber plug 16 and aluminum shell 11 is enhanced, which can better protect the key components such as electrolyte and electrode inside the capacitor and maintain the stability of the internal environment of the capacitor. Secondly, when the capacitor is affected by external factors such as vibration, impact or temperature change, the rubber plug 16 will not easily displace or loosen, ensuring the integrity and reliability of the sealing structure.

[0039] Through the above technical scheme:

[0040] In use, the sealing sleeve 2 outside the cover plate 15 is embedded in the inside of the sealing ring 3, the first tooth ring block 4 of the outer wall of the sealing sleeve 2 is embedded in the first embedding groove 5 opened in the inner wall of the sealing ring 3, which can provide additional sealing effect for the aluminum electrolytic capacitor, combined with the sealing of the rubber plug 16, forming double insurance, ensuring the stability of the capacitor, avoiding the disadvantages of single rubber plug 16 sealing, which causes loose or displacement and affects the sealing effect, the additional sealing can share the external force to a certain extent, ensure the stability of the overall sealing, ensure that the internal environment of the capacitor is not disturbed by external factors, and maintain the stability of the capacitor performance.

[0041] Further, referring to Figures 6-8 As shown in the figure, the aluminum electrolytic capacitor body 1 is provided with a pressure balance structure 8, the pressure balance structure 8 is opened in the placing groove 81 of the upper end face of the cover plate 15, the lower end of the placing groove 81 and the upper end face of the rubber plug 16 are throughly opened into a through groove 82, and the inside of the placing groove 81 is provided with a fixing ring 83, and the inner surface of the fixing ring 83 is fixedly connected with a pressure balance film 84.

[0042] The pressure balance film 84 comprises a protective layer 841, a gas selective permeation layer 842 and a base layer 843, the gas selective permeation layer 842 is arranged between the protective layer 841 and the base layer 843, the protective layer 841 is made of polyamide material, has good wear resistance and chemical resistance, and can protect the internal gas selective permeation layer 842 from damage by the external environment, the gas selective permeation layer 842 is a microporous membrane made of polytetrafluoroethylene, has excellent chemical stability and hydrophobicity, can effectively filter out liquid components, and only allows gas molecules to enter and exit, the base layer 843 is made of polyethylene terephthalate material, has high tensile strength and good dimensional stability, and provides basic physical strength for the whole pressure balance film 84, preventing the film from being easily broken during use.

[0043] The outer surface of the fixing ring 83 is fixedly connected with a sealing ring 85, the sealing ring 85 is fixedly connected to the inner surface of the placing groove 81, the upper end face of the placing groove 81 is fixedly connected with an upper ring block 87, the lower end face of the upper ring block 87 is fixedly connected with a top pressing block 86, the lower end face of the top pressing block 86 is in contact with the upper end face of the sealing ring 85, the sealing ring 85 can effectively fill the possible small gap between the placing groove 81 and the fixing ring 83, prevent the outside liquid, gas and other impurities from entering the inside of the aluminum electrolytic capacitor body 1, and ensure the stability of the internal environment of the aluminum electrolytic capacitor, while the upper ring block 87 and the top pressing block 86 play a fixing and compacting role on the sealing ring 85, so that the sealing ring 85 will not be displaced or deformed due to factors such as vibration and temperature change during long-term use, thereby always maintaining good sealing effect.

[0044] Specifically, when there is a difference between the internal pressure and the external pressure of the aluminum electrolytic capacitor body 1, gas molecules will enter the placement groove 81 through the through groove 82 according to the pressure difference, flow through the pressure balance film 84, if the internal pressure is high, the gas will flow from the inside to the outside through the pressure balance film 84, if the internal pressure is low, the gas will flow from the outside to the inside through the pressure balance film 84, thereby achieving the balance of the internal and external pressures, preventing the sealing failure or the shell deformation caused by the too large pressure difference, ensuring the relatively stable internal pressure of the capacitor, keeping the relative stability of the electrode spacing and the electrolyte distribution, reducing the electrical performance changes caused by the pressure fluctuation, enabling the capacitor to work reliably in the circuit, and effectively reducing the probability of the capacitor performance failure caused by the pressure imbalance.

[0045] The above only describes some exemplary embodiments of the present application by way of illustration, without doubt, for those skilled in the art, without departing from the spirit and scope of the present application, the described embodiments can be modified in various ways. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of protection of the present application.

Claims

1. A high reliability, high capacitance aluminum electrolytic capacitor, characterized by, The application relates to an aluminum electrolytic capacitor body (1) which comprises an aluminum shell (11) with a core package (12) arranged in the interior of the aluminum shell (11), the core package (12) comprising, from outside to inside, a first electrolyte (121), a cathode foil (122), a second electrolyte (123) and an anode foil (124), the thickness of the cathode foil (122) being 50 mu m, and the upper end of the core package (12) being provided with an aluminum pad lead-out sheet (13) with a lead wire (14) connected to one end of the aluminum pad lead-out sheet (13). The upper end surface of the aluminum shell (11) is provided with a cover plate (15), the lower end surface of the cover plate (15) is fixedly connected with a rubber plug (16), and the outer portion of the cover plate (15) is sleeved with a sealing sleeve (2), and the outer portion of the sealing sleeve (2) and the inner surface wall of the aluminum shell (11) are connected with a sealing ring (3). The outer surface wall of the sealing sleeve (2) is fixedly connected with a first tooth ring block (4), and the inner surface wall of the sealing ring (3) is provided with a first embedding groove (5) matched with the first tooth ring block (4).

2. A high reliability, high capacitance aluminum electrolytic capacitor as defined in claim 1, wherein: The outer surface wall of the rubber plug (16) is fixedly connected with a second tooth ring block (6), and the inner surface wall of the aluminum shell (11) is provided with a second embedding groove (7) matched with the second tooth ring block (6).

3. A high reliability, high capacitance aluminum electrolytic capacitor as defined in claim 1, wherein: The aluminum electrolytic capacitor body (1) is provided with a pressure balance structure (8), the pressure balance structure (8) is arranged in a placing groove (81) on the upper end surface of the cover plate (15), a through groove (82) is arranged in the lower end of the placing groove (81) and the upper end surface of the rubber plug (16), and the interior of the placing groove (81) is provided with a fixing ring (83), and the inner surface wall of the fixing ring (83) is fixedly connected with a pressure balance film (84).

4. A high reliability, high capacitance aluminum electrolytic capacitor as defined in claim 1, wherein: The pressure balance film (84) comprises a protective layer (841), a gas-selective permeation layer (842) and a base layer (843), and the gas-selective permeation layer (842) is arranged between the protective layer (841) and the base layer (843).

5. A high reliability, high capacitance aluminum electrolytic capacitor as defined in claim 4, wherein: The outer surface wall of the fixing ring (83) is fixedly connected with a sealing ring (85), the sealing ring (85) is fixedly connected to the inner surface wall of the placing groove (81), the upper end surface of the placing groove (81) is fixedly connected with an upper ring block (87), the lower end surface of the upper ring block (87) is fixedly connected with a top pressing block (86), and the lower end surface of the top pressing block (86) is in contact with the upper end surface of the sealing ring (85).

6. A high reliability, high capacitance aluminum electrolytic capacitor as defined in claim 5, wherein: ​

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