CN115376830A - Laminated solid aluminum electrolytic capacitor with good sealing performance - Google Patents

Abstract

A laminated solid aluminum electrolytic capacitor with good sealing performance comprises an insulating shell, a core, sealant, an anode lead-out piece and a cathode lead-out piece, wherein the core is arranged in the insulating shell in a sealing manner through the sealant; one end of the anode lead-out piece is electrically connected with the anode end of the core, the other end of the anode lead-out piece extends out of the insulating shell or the sealant is exposed, one end of the cathode lead-out piece is electrically connected with the cathode end of the core, and the other end of the cathode lead-out piece extends out of the insulating shell or the sealant is exposed. In the invention, the plastic shell is sealed by sealing glue instead of plastic packaging material, so that water vapor can be better prevented from entering the product, one side of the bonding pad section of the anode lead-out piece and the cathode lead-out piece is tightly attached to the insulating shell, and the other side of the bonding pad section is exposed, so that the bonding pad section and the sealant can be covered by solder paste during surface mounting, thereby reducing the water vapor entering the core from the joint of the electrode terminal and the plastic packaging material, and improving the high-humidity tolerance capability of the aluminum electrolytic capacitor.

Description

A laminated solid aluminum electrolytic capacitor with good airtightness

technical field

The invention relates to a solid aluminum electrolytic capacitor, in particular to a laminated solid aluminum electrolytic capacitor with good sealing performance.

Background technique

The laminated solid aluminum electrolytic capacitor replaces the liquid electrolyte with a solid conductive polymer, and connects the cores in parallel in a laminated manner. Compared with the liquid aluminum electrolytic capacitor, the manufactured capacitor has a smaller volume and an equivalent series resistance (ESR ) Smaller, wide temperature and more environmentally friendly and many other advantages, in line with the development trend of miniaturization and high frequency of electronic products, and meet the requirements of surface mount technology (SMT).

As shown in the patent (202122073854.0), the laminated solid aluminum electrolytic capacitor uses a monolithic capacitor core as the basic unit. The monolithic positive end includes a porous aluminum foil and an aluminum oxide dielectric layer formed on the surface of the porous aluminum foil, and the negative end includes a porous aluminum foil. And the aluminum oxide dielectric layer on its surface, the first cathode of solid electrolyte formed on the surface of the dielectric layer, the carbon layer and silver layer formed on the solid electrolyte (that is, the second cathode and the third cathode). The positive end of the single piece is welded together with the positive lead-out terminal, and the negative end of the single piece and the negative lead-out terminal are laminated and bonded together by metal paste. The laminated body is layered, and then the laminated body is packaged with a plastic encapsulant, and bonded to the lower surface of the laminated solid capacitor by bending twice, thereby forming a laminated solid aluminum electrolytic capacitor.

Since the molding compound itself is not completely waterproof and has water absorption, and after reflow soldering during mounting, due to the difference in expansion coefficient between the molding compound and the lead-out terminal, after thermal expansion and contraction, gaps may appear at the junction. In the existing laminated solid aluminum electrolytic capacitors, under high temperature and high humidity conditions, water vapor or air can pass through the joint gap and the molding compound body, and enter the core, resulting in deterioration of product characteristics.

Contents of the invention

The technical problem to be solved by the invention is to overcome the deficiencies of the prior art and provide a laminated solid aluminum electrolytic capacitor with good sealing performance.

In order to solve the above technical problems, the technical solution proposed by the present invention is: a laminated solid aluminum electrolytic capacitor with good airtightness, including an insulating case, a core, a sealant, an anode lead-out piece and a cathode lead-out piece, the core It is sealed and arranged in the insulating shell by sealant; one end of the anode lead-out piece is electrically connected to the anode terminal of the core, the other end protrudes from the insulating shell or the sealant is exposed, and one end of the cathode lead-out piece is connected to the cathode end of the core Electrical connection, the other end sticks out of the insulating shell or the sealant is exposed.

For the above laminated solid aluminum electrolytic capacitor with good airtightness, preferably, the sealant is filled in the insulating case, and the sealant fills the core in the insulating case.

For the above-mentioned laminated solid aluminum electrolytic capacitor with good airtightness, preferably, both the anode lead-out piece and the cathode lead-out piece are in a Z shape; the anode lead-out piece and the cathode lead-out piece both include a connection section, a lead-out section and a pad section, so The connection section of the anode lead-out piece and the connection section of the cathode lead-out piece are electrically connected to the anode end and the cathode end of the core respectively, and the pad sections of the anode lead-out piece and the cathode lead-out piece are exposed on the outside of the insulating shell and the sealant .

For the above-mentioned laminated solid aluminum electrolytic capacitor with good airtightness, preferably, one side of the lead-out sections of the anode lead-out piece and the cathode lead-out piece is embedded on the inner wall of the insulating case, and the other side is sealed and connected with the sealant.

For the above-mentioned laminated solid aluminum electrolytic capacitor with good airtightness, preferably, the connecting section of the cathode lead-out piece is connected to the cathode end of the core through conductive paste, and the connecting section of the anode lead-out piece is connected through conductive paste or welding on the anode end of the core.

For the above-mentioned laminated solid aluminum electrolytic capacitor with good airtightness, preferably, the core includes one or more single pieces, and multiple single pieces are laminated to form a core; the single piece includes an anode, a negative electrode and an insulating glue , the isolation glue is arranged between the anode and the cathode; the anode includes a valve metal foil and an oxide film formed on the valve metal foil, and the cathode includes a valve metal foil, an oxide film formed on the valve metal foil, a polymer A conductive polymer layer and a cathode extraction layer, the high molecular conductive polymer layer is formed on the surface of the oxide film, and the cathode extraction layer is on the surface of the high molecular conductive polymer layer.

For the above-mentioned laminated solid aluminum electrolytic capacitor with good airtightness, preferably, the cathode lead-out layer includes a carbon layer and a conductive adhesive layer, the carbon layer is formed on the surface of the polymer conductive polymer layer, and the conductive adhesive layer is formed on the carbon surface.

For the above-mentioned laminated solid aluminum electrolytic capacitor with good airtightness, preferably, after multiple monoliths are stacked together, the conductive adhesive layers at the cathode ends of two adjacent monoliths are connected together, and the adjacent two monoliths are connected together. The anode ends of the sheets are joined together by soldering.

For the above-mentioned laminated solid aluminum electrolytic capacitor with good airtightness, preferably, the cathode lead-out layer includes a carbon layer and a silver paste layer, the carbon layer is formed on the surface of the polymer conductive polymer layer, and the silver paste layer is formed on the carbon surface.

For the above-mentioned laminated solid aluminum electrolytic capacitor with good airtightness, preferably, after multiple pieces of the single pieces are stacked together, the silver paste layers at the cathode ends of the adjacent two pieces are electrically connected together, and the adjacent two pieces The anode ends of the monoliths are joined together by soldering.

Compared with the prior art, the advantage of the present invention is that: in the present invention, the packaging is carried out with a plastic shell and a sealant instead of a plastic encapsulant, which can better prevent water vapor from entering the interior of the product, and the pad sections of the anode lead-out piece and the cathode lead-out piece One side is close to the insulating shell, and the other side is exposed. During surface mounting, the solder paste will cover the joint between the pad segment and the sealant, which can reduce water vapor from entering the core from the joint between the electrode terminal and the plastic encapsulant. . At the same time, in the present invention, the anode lead-out piece and the cathode lead-out piece are all in a Z shape; the connecting section of the anode lead-out piece and the cathode lead-out piece goes deep into the top of the insulating surgery and is electrically connected with the cathode end and the anode end of the core, so that water vapor can pass through The distance between the junction of the anode lead-out piece and the cathode lead-out piece and the filling glue into the inside of the core becomes longer, which makes it more difficult for water vapor to enter the inside of the core.

Description of drawings

FIG. 1 is a schematic cross-sectional structural view of a laminated solid aluminum electrolytic capacitor with good airtightness in Example 1. FIG.

FIG. 2 is a schematic bottom view of the laminated solid aluminum electrolytic capacitor with good airtightness before glue filling in Example 1. FIG.

FIG. 3 is a schematic top view structural view of a laminated solid aluminum electrolytic capacitor with good airtightness in Example 1. FIG.

illustration

1. Insulation shell; 2. Core; 21. Isolation glue; 22. Valve metal foil; 23. Oxidation film; 24. Polymer conductive polymer layer; 25. Carbon layer; 26. Silver paste layer; 27. Welding 3. Sealant; 4. Cathode leading piece; 5. Cathode leading piece; 6. Connecting section; 7. Leading section; 8. Pad section; 9. Conductive paste;

Detailed ways

In order to facilitate the understanding of the present invention, the present invention will be described more fully and in detail below in conjunction with the accompanying drawings and preferred embodiments, but the protection scope of the present invention is not limited to the following specific embodiments.

It should be noted that when an element is described as "fixed, affixed, connected or communicated with" another element, it may be directly fixed, affixed, connected or communicated with another element , can also be indirectly fixed, affixed, connected or communicated with another element through other intermediate connectors.

Unless otherwise defined, all technical terms used hereinafter have the same meanings as commonly understood by those skilled in the art. The terminology used herein is only for the purpose of describing specific embodiments, and is not intended to limit the protection scope of the present invention.

Example 1

As shown in Figure 1 and Figure 2, a laminated solid aluminum electrolytic capacitor with good sealing performance includes an insulating case 1, a core 2, a sealant 3, an anode lead-out piece 4 and a cathode lead-out piece 5, and the core 2 passes through The sealant 3 is sealed and arranged in the insulating shell 1; one end of the anode lead-out piece 4 is electrically connected to the anode end of the core 2, the other end extends out of the insulating shell 1 or the sealant 3 is exposed, and one end of the cathode lead-out piece 5 is connected to the anode end of the core 2. The cathode end of the core 2 is electrically connected, and the other end protrudes from the insulating shell 1 or the sealant 3 is exposed. In this embodiment, the sealant 3 is filled in the insulating case 1 , and the sealant 3 fills the core 2 in the insulating case 1 . In this embodiment, the sealant 3 may be epoxy resin glue.

In this embodiment, the structures of the anode lead-out piece 4 and the cathode lead-out piece 5 are similar. Both the anode lead-out piece 4 and the cathode lead-out piece 5 are Z-shaped; the anode lead-out piece 4 and the cathode lead-out piece 5 both include a connection section 6, a lead-out section 7 and a pad section 8, and the connection section 6 of the anode lead-out piece 4 and the cathode lead-out piece The connecting section 6 of 5 is electrically connected to the anode terminal and the cathode terminal of the core 2 respectively, and the pad sections 8 of the anode lead-out piece 4 and the cathode lead-out piece 5 are exposed on the outside of the insulating case 1 and the sealant 3 .

In this embodiment, as shown in Figure 1, the connection section 6, the lead-out section 7 and the pad section 8 of the anode lead-out piece 4 and the cathode lead-out piece 5 are all integrally formed, that is to say, the anode lead-out piece 4 and the cathode lead-out piece The connection section 6, the lead-out section 7 and the pad section 8 of the sheet 5 are all a sheet bent into a Z shape. One side of the connection section 6 of the anode lead-out piece 4 is embedded on the inner wall of the bottom surface of the insulating shell, and the other side is connected to the anode end through the conductive paste 9, and one side of the lead-out section 7 of the anode lead-out piece 4 is embedded in the vertical wall of the insulating shell 1. The straight side wall and the other side are sealed and connected to the sealant 3 , and the pad segment 8 of the anode lead-out piece 4 is exposed on the outside of the sealant 3 . As shown in FIG. 1 and FIG. 3 , one side of the pad segment 8 of the anode lead-out piece 4 is closely attached to the insulating shell, and the other side is exposed. The structure of the cathode lead-out piece 5 is similar to that of the anode lead-out piece 4 . One side of the connection section 6 of the cathode lead-out piece 5 is embedded on the inner wall of the bottom surface of the insulating shell, and the other side is connected to the cathode terminal through the conductive paste 9, and one side of the lead-out section 7 of the cathode lead-out piece 5 is embedded in the vertical wall of the insulating shell 1. The straight side wall and the other side are sealed and connected to the sealant 3 , and the pad segment 8 of the cathode lead-out piece 5 is exposed on the outside of the sealant 3 .

In this embodiment, the connection section 6 of the anode lead-out piece 4 and the cathode lead-out piece 5 can be glued to the inner wall of the bottom surface of the insulating shell, and the lead-out section 7 of the anode lead-out piece 4 and the cathode lead-out piece 5 can also be connected to the insulating shell by glue. Vertical side walls are fixedly connected.

In this embodiment, the core 2 includes one or more single pieces, and multiple single pieces are laminated to form the core 2; the single piece includes an anode, a negative electrode and an insulating glue 21, and the insulating glue 21 is arranged between the anode and the cathode The anode includes a valve metal foil 22 and an oxide film 23 formed on the valve metal foil 22, and the cathode includes a valve metal foil 22, an oxide film 23 formed on the valve metal foil 22, a polymer conductive polymer layer 24 and The cathode extraction layer, the high molecular conductive polymer layer 24 is formed on the surface of the oxide film 23 , and the cathode extraction layer is on the surface of the high molecular conductive polymer layer 24 . In this embodiment, the valve metal foil 22 is a porous aluminum foil, and the oxide film 23 is an aluminum oxide film.

In this embodiment, as shown in Figure 1, the core 2 includes 5 single pieces, and the 5 single pieces are laminated to form the core 2; the single piece includes an anode, a negative electrode and an insulating glue 21, and the insulating glue 21 is arranged on the anode Between the anode and the cathode, it plays the role of isolating the anode and the cathode; the anode includes a valve metal foil 22 and an oxide film 23 formed on the valve metal foil 22, and a welding hole 10 is arranged on the anode. The cathode includes a valve metal foil 22, an oxide film 23 formed on the valve metal foil 22, a polymer conductive polymer layer 24, and a cathode extraction layer. The surface of the conductive polymer layer 24. In this embodiment, the valve metal foils 22 of the anode and the cathode are the same piece, and the oxide film 23 is formed on the valve metal foil 22 . The cathode drawing layer includes a carbon layer 25 and a silver paste layer 26 , the carbon layer 25 is formed on the surface of the polymer conductive polymer layer 24 , and the silver paste layer 26 is formed on the surface of the carbon layer 25 .

In the present embodiment, after five monoliths are stacked together, the silver paste layers 26 at the cathode ends of two adjacent monoliths are connected together, and the anode ends of two adjacent monoliths are connected by welding melt 27 Together, the anode is welded to the welding melt 27 through the welding hole 10 . In this embodiment, the silver paste layer 26 can be replaced by a conductive adhesive layer.

When preparing the laminated solid aluminum electrolytic capacitor with good airtightness of this embodiment, the anode lead-out piece 4 and the cathode lead-out piece 5 are fixedly connected to the preset position on the inner wall of the insulating case 1, and then the core The anode end and the cathode end of 2 are electrically connected to the connection section 6 of the anode lead-out piece 4 and the cathode lead-out piece 5 through the conductive paste 9 . Finally, it is filled and sealed with epoxy resin glue.

In this embodiment, the packaging is carried out with a plastic shell and a sealant 3 instead of the plastic compound, which can better prevent water vapor from entering the interior of the product. The other side is exposed, and the solder paste will cover the junction of the pad segment 8 and the sealant 3 during surface mounting, which can reduce water vapor from entering the interior of the core 2 from the junction of the electrode terminal and the molding compound. Simultaneously in the present invention, the anode lead-out piece 4 and the cathode lead-out piece 5 are all Z-shaped; In this way, the distance for water vapor to enter the interior of the core 2 through the junction of the anode lead-out piece 4 and the cathode lead-out piece 5 and the filling glue becomes longer, thereby increasing the difficulty for water vapor to enter the inside of the core 2.

Claims (10)

1. A laminated solid aluminum electrolytic capacitor with good airtightness is characterized in that: it comprises an insulating case, a core, a sealant, an anode lead-out sheet and a cathode lead-out sheet, and the core is sealed and arranged on the insulating case by a sealant In the body; one end of the anode lead-out piece is electrically connected to the anode terminal of the core, and the other end extends out of the insulating shell or the sealant is exposed; one end of the cathode lead-out piece is electrically connected to the cathode end of the core, and the other end extends out The insulating shell or sealant is exposed. 2. The laminated solid aluminum electrolytic capacitor with good airtightness according to claim 1, characterized in that: the sealant is filled in the insulating case, and the sealant fills the core in the insulating case. 3. The laminated solid aluminum electrolytic capacitor with good airtightness according to claim 1, characterized in that: the anode lead-out piece and the cathode lead-out piece are both in a Z shape; the anode lead-out piece and the cathode lead-out piece both include connecting sections, Lead-out section and pad section, the connection section of the anode lead-out piece and the connection section of the cathode lead-out piece are electrically connected to the anode end and the cathode end of the core respectively, and the pad sections of the anode lead-out piece and the cathode lead-out piece are all exposed on the Insulate the outside of the housing and sealant. 4. The laminated solid aluminum electrolytic capacitor with good airtightness according to claim 3, characterized in that: one side of the lead-out section of the anode lead-out piece and the cathode lead-out piece is embedded on the inner wall of the insulating case, and the other The side is sealed with a sealant. 5. The laminated solid aluminum electrolytic capacitor with good airtightness according to claim 3, characterized in that: the connection section of the cathode lead-out piece is connected to the cathode end of the core through conductive paste, and the connection section of the anode lead-out piece The connection segment is connected to the anode end of the core by conductive paste or welding. 6. The laminated solid aluminum electrolytic capacitor with good airtightness according to any one of claims 1-5, characterized in that: the core comprises one or more single pieces, and multiple single pieces are laminated to form a core The monolith includes an anode, a negative electrode and a spacer, and the spacer is arranged between the anode and the cathode; the anode includes a valve metal foil and an oxide film formed on the valve metal foil, and the cathode includes a valve metal The oxide film formed on the foil, the valve metal foil, the high molecular conductive polymer layer and the cathode extraction layer, the high molecular conductive polymer layer is formed on the surface of the oxide film, and the high molecular conductive polymer layer is formed on the surface of the high molecular conductive polymer layer . 7. The laminated solid aluminum electrolytic capacitor with good airtightness according to claim 6, characterized in that: the cathode lead-out layer comprises a carbon layer and a conductive adhesive layer, and the carbon layer is formed on the surface of the polymer conductive polymer layer , the conductive adhesive layer is formed on the surface of the carbon layer. 8. The laminated solid aluminum electrolytic capacitor with good airtightness according to claim 7, characterized in that: after a plurality of said monoliths are stacked together, the conductive adhesive layers at the cathode ends of two adjacent monoliths are connected Together, the anode ends of two adjacent single pieces are connected together by welding melt. 9. The laminated solid aluminum electrolytic capacitor with good airtightness according to claim 6, characterized in that: the cathode lead-out layer comprises a carbon layer and a silver paste layer, and the carbon layer is formed on the surface of the polymer conductive polymer layer , the silver paste layer is formed on the surface of the carbon layer. 10. The laminated solid aluminum electrolytic capacitor with good airtightness according to claim 9, characterized in that: after a plurality of said monoliths are stacked together, the silver paste layers at the cathode ends of two adjacent monoliths are electrically connected to each other. Together, the anode ends of two adjacent single pieces are connected together by welding melt.

Images