electrolytic capacitor

Abstract

This electrolytic capacitor comprises: a capacitor element having a bottom surface B and an upper surface T and including a positive electrode lead; a negative electrode lead terminal; and an exterior resin. The negative electrode lead terminal comprises: a negative electrode terminal part having an exposed surface exposed to the bottom surface B; and two negative electrode anchor parts extending from the negative electrode terminal part and embedded in the exterior resin. The negative electrode terminal part has two end sides E along the extension direction of the positive electrode lead, and the two negative electrode anchor parts each include a negative electrode upright part, which extends up from the end side E of the negative electrode terminal part toward the upper surface T, and a first extension part and a second extension part, which extend from the negative electrode upright part.

Description

[Technical Field]

[0001] The present disclosure relates to electrolytic capacitors. [Background technology]

[0002] Electrolytic capacitors are installed in a variety of electronic devices. Electrolytic capacitors typically include an anode lead terminal and a cathode lead terminal that are electrically connected to a capacitor element, and an exterior resin that covers the capacitor element.

[0003] Patent Documents 1 and 2 disclose cathode lead terminals that facilitate the positioning of a capacitor element. Specifically, Patent Document 1 discloses bending both sides of the cathode lead terminal upward to form a fitting portion, and placing a capacitor element in the fitting portion. Patent Document 2 discloses providing a cathode lead frame with a pair of side portions facing each other, and placing a capacitor element between the pair of side portions. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-068576 [Patent Document 2] Japanese Patent Application Laid-Open No. 2009-141208 Summary of the Invention [Problem to be solved by the invention]

[0005] The lead terminals include terminal portions with exposed surfaces that are exposed on the bottom surface of the electrolytic capacitor, and these exposed surfaces can serve as bonding surfaces for connecting to printed circuit boards, etc. However, expansion of the lead terminals during reflow processing can cause the terminal portions to separate from the bottom surface of the electrolytic capacitor (the exposed surfaces of the terminal portions can lift up from the bottom surface of the electrolytic capacitor), so there is a demand for improved terminal strength. [Means for solving the problem]

[0006] One aspect of the present disclosure relates to an electrolytic capacitor having a bottom surface and an upper surface opposite to the bottom surface, the electrolytic capacitor including a capacitor element including an anode lead, an anode lead terminal and a cathode lead terminal electrically connected to the capacitor element, and an exterior resin disposed around the capacitor element, the cathode lead terminal including a cathode terminal portion having an exposed surface exposed at the bottom surface and two cathode anchor portions extending from the cathode terminal portion and embedded in the exterior resin, the cathode terminal portion being connected to the anode lead Longitudinal the two cathode anchor portions each include a cathode upright portion that stands from the end side of the cathode terminal portion toward the upper surface, a first extension portion that extends from the cathode upright portion, and a second extension portion that extends from the first extension portion. The first extension portion is bent from the upper end of the cathode standing portion, and the second extension portion stands up toward the upper surface. The two cathode anchors On the other hand Said first extension part the first extension portion of the other of the two cathode anchor portions teeth , mutual The two cathode anchor portions extend in a direction away from each other. The one Said second extension part and the second extension portion of the other of the two cathode anchor portions. teeth ,before The anode lead Longitudinal The capacitor element is sandwiched between the electrodes in a direction perpendicular to the direction of the electrode. [Effects of the Invention]

[0007] According to the present disclosure, in an electrolytic capacitor, it is possible to increase the terminal strength while suppressing misalignment of the capacitor element. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view schematically illustrating a configuration of an example of an electrolytic capacitor according to the present disclosure. [Figure 2] FIG. 2 is a perspective view schematically showing some members of the electrolytic capacitor shown in FIG. [Figure 3] 2 is a cross-sectional view schematically showing an anode lead terminal of the electrolytic capacitor shown in FIG. 1. [Figure 4] 2 is a cross-sectional view schematically showing a cathode lead terminal of the electrolytic capacitor shown in FIG. 1. [Figure 5] FIG. 2 is a bottom view schematically showing the electrolytic capacitor shown in FIG. [Figure 6] FIG. 2 is a cross-sectional view schematically showing the electrolytic capacitor shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] The following describes embodiments of the present disclosure using examples, but the present disclosure is not limited to the examples described below. While specific numerical values ​​and materials are used as examples in the following description, other numerical values ​​and materials may be used as long as the effects of the present disclosure are obtained. Note that components other than those characteristic of the present disclosure may be those of known electrolytic capacitors.

[0010] (electrolytic capacitor) The electrolytic capacitor of the present disclosure has a bottom surface and a top surface opposite the bottom surface. Hereinafter, the bottom surface and the top surface may be referred to as the "bottom surface (B)" and the "top surface (T)." The electrolytic capacitor of the present disclosure includes a capacitor element including an anode lead, an anode lead terminal and a cathode lead terminal electrically connected to the capacitor element, and an exterior resin disposed around the capacitor element.

[0011] The cathode lead terminal includes a cathode terminal portion having an exposed surface exposed on the bottom surface (B) and two cathode anchor portions extending from the cathode terminal portion and embedded in the exterior resin. Hereinafter, the cathode lead terminal including the two cathode anchor portions may be referred to as a "lead terminal (L)." The cathode terminal portion extends in the direction D1 of the anode lead extension. (Longitudinal direction of anode lead) Each of the two cathode anchor portions includes a cathode upstanding portion that rises from the end edge of the cathode terminal portion toward the upper surface (T), and a first extension portion that extends in a bent state from the upper end of the cathode upstanding portion.

[0012] As described above, the cathode anchor portion (cathode standing portion and cathode extension portion) is embedded in the exterior resin. Furthermore, the metal sheet constituting the lead terminal (L) is bent at two locations: the boundary between the cathode terminal portion and the cathode standing portion, and the boundary between the cathode standing portion and the first extension portion. With this configuration, the extending direction of the cathode standing portion differs from the extending direction of the first extension portion.

[0013] Furthermore, the two cathode anchor portions are bent in different directions (counter-rotation directions) at the boundary between the cathode terminal portion and the cathode upright portion and at the boundary between the cathode upright portion and the first extension portion. Here, "bent in different directions" means that the metal sheet constituting the lead terminal (L) is bent so that one surface (the surface on the upper surface (T) side) of the metal sheet forms a valley at the boundary between the cathode terminal portion and the cathode upright portion, and is bent so that the one surface forms a peak at the boundary between the cathode upright portion and the first extension portion. More specifically, the first extension portions of the two cathode anchor portions are bent from the upper ends of the cathode upright portion and extend in directions away from each other. That is, the first extension portions of the two cathode anchor portions are bent from the upper ends of the cathode upright portion and extend in directions away from each other in direction D2 perpendicular to direction D1 in which the anode lead extends.

[0014] The two cathode anchor portions (the cathode standing portion and the first extension portion) provide a high anchor effect, increasing the terminal strength. In particular, because the entire surface of the cathode standing portion is covered with the exterior resin, the cathode terminal portion is prevented from separating from the exterior resin (the bottom surface of the electrolytic capacitor).

[0015] On the surface of the cathode terminal, Opposition In this case, the exterior resin penetrates between the capacitor element and the cathode terminal, the capacitor element is more stably fixed by the exterior resin, and the cathode terminal is further prevented from separating from the exterior resin, thereby enhancing the anchor effect.

[0016] The two cathode anchor portions further include a second extension portion extending from the first extension portion. Hereinafter, the first extension portion and the second extension portion may be collectively referred to as the cathode extension portion. The second extension portions of the two cathode anchor portions each rise toward the upper surface (B). The second extension portion bends from the outer end of the first extension portion (the end opposite the cathode upright portion) and extends toward the upper surface (B), and the extending direction of the first extension portion and the extending direction of the second extension portion are different. Therefore, by further providing the second extension portion in addition to the first extension portion, the anchoring effect of the cathode anchor portion is further enhanced.

[0017] The second extension portions of the two cathode anchor portions each rise toward the upper surface (B) and are provided so as to sandwich the capacitor element in direction D2 perpendicular to direction D1 in which the anode lead extends. The second extension portions prevent the capacitor element from shifting in position. As a result, the two cathode anchor portions can serve both to position the capacitor element and to prevent the cathode terminal from separating from the exterior resin.

[0018] There are no particular limitations on the size of the cathode anchor portion as long as it is a size that provides an anchoring effect. The two cathode anchor portions included in one cathode lead terminal (L) are usually symmetrical with respect to a plane that is perpendicular to the bottom surface (B) and passes through the central axis of the anode lead, but they do not have to be symmetrical.

[0019] In the electrolytic capacitor of the present disclosure, the cathode lead terminal may include a cathode connecting portion extending from the cathode terminal portion and embedded in the exterior resin. The cathode connecting portion is electrically connected to the cathode portion of the capacitor element. In this case, the cathode connecting portion may be in contact with the bottom surface of the capacitor element via a conductive adhesive layer, and the second extension portion may be in contact with the side surface of the capacitor element via a conductive adhesive layer. This increases the contact area between the capacitor element and the cathode lead terminal, which is advantageous for reducing the equivalent series resistance (ESR). Note that, from the standpoint of design, such as simplifying the manufacturing process and tolerance, the second extension portion may be in direct contact with the side surface of the capacitor element without providing a conductive adhesive layer, or the second extension portion may be in contact with the side surface of the capacitor element via the exterior resin.

[0020] In the electrolytic capacitor of the present disclosure, it is preferable that the entire surface of the cathode extension portion (excluding the area in contact with the conductive adhesive layer when the second extension portion is in contact with the side surface of the capacitor element via the conductive adhesive layer) be in contact with the exterior resin. From another perspective, it is preferable that the cathode anchor portion is not in contact with the capacitor element. In this case, a high anchor effect is easily obtained for the cathode lead terminal.

[0021] In the electrolytic capacitor of the present disclosure, the anode lead terminal may include an anode terminal portion having an exposed surface exposed on the bottom surface (B). The anode lead terminal preferably includes an anode connection portion extending from the anode terminal portion and embedded in the exterior resin, and the anode connection portion is electrically connected to the anode lead. The anode connection portion preferably rises from the anode terminal portion toward the upper surface and has a groove at its upper end that receives the tip of the anode lead. In this case, the capacitor element can be positioned using the groove in the anode connection portion together with the second extension portions of the two cathode anchor portions. That is, the capacitor element can be positioned using one point on the tip of the anode lead and two points on both side surfaces of the capacitor element (both side surfaces perpendicular to the bottom surface (B) and sandwiched between direction D2 perpendicular to direction D1 in which the anode lead extends). The two second extensions sandwich both side surfaces of the capacitor element in the region of the end of the cathode anchor part (above the cathode terminal part) opposite the tip of the anode lead, thereby effectively positioning the capacitor element at the three points described above, which significantly improves the positioning accuracy of the capacitor element and significantly reduces misalignment of the capacitor element.

[0022] Without providing a cathode anchor part, the cathode connection described below Department If side walls for positioning the capacitor element (side walls rising from both sides of the cathode connection part) are provided on both sides, the anchor effect of the cathode anchor part cannot be obtained, and the cathode terminal part cannot be prevented from separating from the exterior resin. The second extension part is located farther from the tip of the anode lead than the above-mentioned side walls, and the capacitor element can be more effectively positioned using the above three points.

[0023] In the electrolytic capacitor according to the present disclosure, the anode lead terminal may include two anode anchor portions. That is, the anode lead terminal may include an anode terminal portion having an exposed surface exposed on the bottom surface (B), and may include two anode anchor portions extending from the anode terminal portion and embedded in the exterior resin. The anode terminal portion may have two end sides along the direction in which the anode lead extends, and each of the two anode anchor portions may include an anode upright portion that rises from the end side of the anode terminal portion toward the top surface (T) and an anode extension portion that bends and extends from the upper end of the anode upright portion. The anode anchor portions have a high anchoring effect, and the anode terminal portion is prevented from separating from the exterior resin.

[0024] The two anode anchor portions may be bent in different directions (counter-rotating directions) at the boundary between the anode terminal portion and the anode upright portion and at the boundary between the anode upright portion and the anode extension portion, respectively. Here, "bent in different directions" means that the metal sheet constituting the anode lead terminal is bent so that one surface (the surface on the upper surface (T) side) of the metal sheet forms a valley at the boundary between the anode terminal portion and the anode upright portion, and is bent so that this one surface forms a peak at the boundary between the anode upright portion and the anode extension portion. More specifically, the anode extension portions of the two anode anchor portions may be bent from the upper ends of the anode upright portion and extend in directions away from each other. That is, the anode extension portions of the two anode anchor portions may be bent from the upper ends of the anode upright portion and extend in directions away from each other in a direction perpendicular to the extension direction of the anode lead. An anchor portion with this configuration is easy to form. Furthermore, when an anchor portion with this configuration is used, it is easy to fill the exterior resin material (such as a mold resin). The two anode anchor portions may be bent in the same direction (same rotational direction) at the boundary between the anode terminal portion and the anode upright portion, and at the boundary between the anode upright portion and the anode extension portion, respectively.

[0025] In the electrolytic capacitor of the present disclosure, it is preferable that the entire surface of the anode extension portion be in contact with the exterior resin. In this case, a high anchoring effect is easily obtained for the anode lead terminal. The size of the anode anchor portion is not particularly limited as long as it is a size that provides an anchoring effect. The two anode anchor portions included in one anode lead terminal are usually symmetrical with respect to a plane that is perpendicular to the bottom surface (B) and passes through the central axis of the anode lead, but they do not have to be symmetrical.

[0026] An example of the components of the electrolytic capacitor of the present disclosure will be described below.

[0027] (Anode lead terminal) The anode lead terminal may be formed by processing a single metal sheet using a known metal processing method. The material of the anode lead terminal may be any material that can be used as a material for an anode lead terminal of an electrolytic capacitor. For example, a known anode lead terminal material used in electrolytic capacitors may be used. The anode lead terminal may be formed by processing a metal sheet (including a metal plate and a metal foil) made of a metal (such as copper or a copper alloy). The surface of the metal sheet may be plated with nickel, gold, or the like. The thickness of the metal sheet constituting the anode lead terminal may be in the range of 25 μm to 200 μm (for example, in the range of 25 μm to 100 μm).

[0028] As described above, the anode lead terminal may include an anode terminal portion exposed on the bottom surface (B) and an anode connection portion (hereinafter also referred to as a wire connection portion) rising from the anode terminal portion toward the top surface (T). As described above, two anchor portions may extend from the anode terminal portion. An anode lead of a capacitor element is connected to the wire connection portion. The wire connection portion may have a wire receiving portion at its tip that is bent to be approximately parallel to the bottom surface (B). The wire receiving portion may be bent toward the front surface of the capacitor element, or may be bent in the opposite direction. Here, the front surface of the capacitor element is the surface facing the end surface of the capacitor element from which the wire protrudes. The wire receiving portion enables the wire connection portion and the anode lead to be connected easily and reliably.

[0029] (cathode lead terminal) The cathode lead terminal may be formed by processing a single metal sheet using a known metal processing method. The material of the cathode lead terminal may be any material that can be used as a cathode lead terminal material for electrolytic capacitors. For example, a known cathode lead terminal material used in electrolytic capacitors may be used. The cathode lead terminal may be formed from a metal sheet exemplified as a material for an anode lead terminal.

[0030] (Capacitor element) The capacitor element is not particularly limited. The capacitor element may be a capacitor element used in a known solid electrolytic capacitor or a capacitor element having a similar configuration. The electrolytic capacitor of the present disclosure may include multiple capacitor elements. In this case, the anode portions of the multiple capacitors are electrically connected to an anode lead terminal.

[0031] An example capacitor element includes an anode portion and a cathode portion. The anode portion includes an anode body having a dielectric layer formed on its surface and an anode lead, and the cathode portion includes an electrolyte layer and a cathode layer. The electrolyte layer is disposed between the dielectric layer formed on the surface of the anode body and the cathode layer. These components are not particularly limited, and components used in known solid electrolytic capacitors may be applied. Examples of these components are described below.

[0032] (anode body) The anode body may be, for example, a columnar (e.g., rectangular) porous sintered body obtained by sintering material particles. Examples of the particles include valve metal particles, valve metal-containing alloy particles, and valve metal-containing compound particles. These particles may be used alone or in combination of two or more. Examples of valve metals include titanium (Ti), tantalum (Ta), and niobium (Nb). Alternatively, the anode body may be formed by roughening the surface of a valve metal-containing substrate (e.g., a foil- or plate-shaped substrate) by etching or other methods.

[0033] The anode part may be fabricated by the following method. First, a portion of the anode lead is embedded in metal powder, which is the material of the anode body, and the metal powder is pressure-molded into a columnar shape (e.g., a rectangular parallelepiped shape). The metal powder is then sintered to form the anode body. In this manner, an anode part including the anode body and the anode lead, part of which is embedded in the anode body, can be fabricated.

[0034] The dielectric layer formed on the surface of the anode body is not particularly limited and may be formed by a known method. For example, the dielectric layer may be formed by immersing the anode body in a chemical conversion solution to anodize the surface of the anode body. Alternatively, the dielectric layer may be formed by heating the anode body in an oxygen-containing atmosphere to oxidize the surface of the anode body.

[0035] (anode lead) The anode lead may be a wire (anode wire) made of metal. Examples of materials for the anode lead include the valve metals mentioned above, copper, aluminum, and aluminum alloys. A portion of the anode lead is embedded in the anode body, and the remaining portion protrudes from the anode body. The anode lead is usually rod-shaped, but may also be plate-shaped.

[0036] (electrolyte layer) The electrolyte layer is not particularly limited, and an electrolyte layer used in a known solid electrolytic capacitor may be applied. In this specification, the term "electrolyte layer" may be read as a "solid electrolyte layer," and the term "electrolytic capacitor" may be read as a "solid electrolytic capacitor." The electrolyte layer may be a laminate of two or more different electrolyte layers.

[0037] The electrolyte layer is disposed so as to cover at least a portion of the dielectric layer. The electrolyte layer may be formed using a manganese compound or a conductive polymer. Examples of conductive polymers include polypyrrole, polythiophene, polyaniline, and derivatives thereof. These may be used alone or in combination. The conductive polymer may also be a copolymer of two or more types of monomers. Note that a derivative of a conductive polymer refers to a polymer having a conductive polymer as its basic skeleton. For example, an example of a polythiophene derivative is poly(3,4-ethylenedioxythiophene).

[0038] A dopant may be added to the conductive polymer. The dopant can be selected depending on the conductive polymer, and known dopants may be used. Examples of dopants include naphthalenesulfonic acid, p-toluenesulfonic acid, polystyrenesulfonic acid, and salts thereof. An example electrolyte layer is formed using poly(3,4-ethylenedioxythiophene) (PEDOT) doped with polystyrenesulfonic acid (PSS).

[0039] The electrolyte layer containing the conductive polymer may be formed by polymerizing raw material monomers on the dielectric layer, or by applying a liquid containing the conductive polymer (and optionally a dopant) to the dielectric layer and then drying it.

[0040] (cathode layer) The cathode layer may be a conductive layer formed on the electrolyte layer, for example, a conductive layer formed so as to cover the electrolyte layer. The cathode layer may include a carbon layer formed on the electrolyte layer and a metal paste layer formed on the carbon layer. The carbon layer may be formed of a conductive carbon material such as graphite and a resin. The metal paste layer may be formed of metal particles (e.g., silver particles) and a resin, for example, a silver paste.

[0041] The cathode layer is electrically connected to a cathode lead terminal. The cathode layer may be electrically connected to the cathode lead terminal via a conductive member. The conductive member may be formed of metal particles (e.g., silver particles) and a resin, for example, a silver paste.

[0042] (exterior resin) The exterior resin is disposed around the capacitor element so that the capacitor element is not exposed on the surface of the electrolytic capacitor. Furthermore, the exterior resin insulates the anode lead terminal from the cathode lead terminal. The exterior resin may be a known exterior resin used in electrolytic capacitors. For example, the exterior resin may be formed using an insulating resin material used to seal the capacitor element. Examples of exterior resin materials include epoxy resin, phenolic resin, silicone resin, melamine resin, urea resin, alkyd resin, polyurethane, polyimide, and unsaturated polyester. The exterior resin may also contain substances other than resin (such as inorganic fillers).

[0043] An example of an electrolytic capacitor according to the present disclosure will be specifically described below with reference to the drawings. The components described above can be applied to the components of the example electrolytic capacitor described below. Furthermore, the components of the example electrolytic capacitor described below can be modified based on the above description. Furthermore, the matters described below may be applied to the above-described embodiment. Furthermore, in the embodiment described below, components that are not essential for the electrolytic capacitor according to the present disclosure may be omitted.

[0044] FIG. 1 is a schematic perspective view of an electrolytic capacitor 100. FIG. 2 is a schematic perspective view of the anode lead terminal 120 and cathode lead terminal 130 of the electrolytic capacitor 100 shown in FIG. 1. FIG. 3 is a cross-sectional view of the anchor portion of the anode lead terminal 120. FIG. 4 is a cross-sectional view of the anchor portion of the cathode lead terminal 130. Note that in FIGS. 3 and 4, for ease of understanding, the position of the capacitor element 110 is indicated by a dotted line, and the outline of the exterior resin 101 is indicated by a solid line. FIG. 5 is a schematic bottom view of the electrolytic capacitor 100 shown in FIG. 1. In FIG. 5, the portion embedded in the exterior resin 101 is indicated by a dotted line. Furthermore, FIG. 6 is a schematic cross-sectional view of the electrolytic capacitor 100 shown in FIG. 1. The cross-sectional view in FIG. 6 is a cross-sectional view passing through the central axis of the anode lead (anode wire) 112. Note that for ease of understanding, in the following figures, some components may be shown only by outline. For example, in FIG. 1, the exterior resin 101 is shown only by the outline represented by a dotted line.

[0045] Electrolytic capacitor 100 has a bottom surface 100b and a top surface 100t opposite bottom surface 100b. Electrolytic capacitor 100 includes a capacitor element 110, an anode lead terminal 120, a cathode lead terminal 130, a conductive member 141, and an exterior resin 101. Anode lead terminal 120 and cathode lead terminal 130 are each electrically connected to capacitor element 110. Anode lead terminal 120 and cathode lead terminal 130 are made of a metal sheet.

[0046] 2, 3, and 5, anode lead terminal 120 includes an anode terminal portion 121, a wire connection portion 122, and two anchor portions 123. A portion of anode terminal portion 121 in the thickness direction is exposed at bottom surface 100b, and anode terminal portion 121 has a first main surface SP1 (exposed surface) exposed at bottom surface 100b. A second main surface SP2 of anode terminal portion 121 opposite first main surface PS1 is in contact with exterior resin 101.

[0047] Wire connection portion 122 rises from anode terminal portion 121 toward upper surface 100t. A groove in wire connection portion 122 for receiving the tip of anode lead 112 is formed by resistance welding anode lead 112 and wire connection portion 122. Anode lead 112 and wire connection portion 122 may be connected by welding, soldering, or the like.

[0048] 1 and 2, the two anode anchor portions 123 extend from two end edges 121e, respectively. The two end edges 121e are end edges of the anode terminal portion 121 and form a pair of end edges along the direction (D1) in which the anode lead 112 extends.

[0049] 1 and 3, each of the two anode anchor portions 123 includes a rising portion 123a that rises from the end edge 121e toward the upper surface 100t and an extending portion 123b that bends and extends from the upper end of the rising portion 123a. The two anode anchor portions 123 are bent in different directions at the boundary between the anode terminal portion 121 and the rising portion 123a and at the boundary between the rising portion 123a and the extending portion 123b. Specifically, one surface (the surface facing the upper surface 100t) of the metal sheet constituting the anode lead terminal 120 is folded in a valley direction at the boundary between the anode terminal portion 121 and the rising portion 123a and is folded in a mountain direction at the boundary between the rising portion 123a and the extending portion 123b. As a result, the extending portion 123b extends from the upper end of the rising portion 123a toward the outside of the electrolytic capacitor 100. That is, extending portions 123b of two anchor portions 123 are bent from the upper ends of upright portions 123a, and extend in directions away from each other in a direction (D2) perpendicular to the direction (D1) in which anode lead 112 extends. The direction in which extending portions 123b extend is approximately parallel to bottom surface 100b, and the angle therebetween may be, for example, within a range of -20° to 20°.

[0050] 2, 4, and 5, cathode lead terminal 130 includes a cathode terminal portion 131, a cathode connection portion 132, and two cathode anchor portions 133. A portion of cathode terminal portion 131 in the thickness direction is exposed at bottom surface 100b, and cathode terminal portion 131 has a first main surface SN1 (exposed surface) exposed at bottom surface 100b. A second main surface SN2 of cathode terminal portion 131 opposite first main surface SN1 is in contact with exterior resin 101.

[0051] 2, 5, and 6, cathode connecting portion 132 is disposed with a step from cathode terminal portion 131, is located slightly closer to top surface 100t than cathode terminal portion 131, and is covered at bottom surface 100b with exterior resin 101. Cathode connecting portion 132 is disposed along bottom surface 100b from one end edge (an end edge continuing to two end edges 131e described below) of cathode terminal portion 131 that is aligned in direction (D2) perpendicular to direction (D1) in which anode lead 112 extends.

[0052] Cathode connecting portion 132 is electrically connected to cathode portion 115 (cathode layer 117), which will be described later, via conductive member 141 (conductive adhesive layer). That is, cathode terminal portion 131 is electrically connected to capacitor element 110 via cathode connecting portion 132 and conductive member 141. There are no particular limitations on conductive member 141, and a known conductive member may be used. For example, conductive member 141 may be formed from a metal paste or the like.

[0053] The two cathode anchor portions 133 extend from two end edges 131e, respectively. The two end edges 131e are end edges of the cathode terminal portion 131 and form a pair of end edges along the direction (D1) in which the anode lead 112 extends.

[0054] Referring to Figures 1 and 4, the two cathode anchor portions 133 each include an upright portion 133a rising from the end edge 131e toward the upper surface 100t, a first extension portion 133b extending from the upright portion 133a, and a second extension portion 133c extending from the first extension portion 133b.

[0055] The first extension portions 133b of the two cathode anchor portions 133 are bent from the upper ends of the upright portions 133a and extend in directions away from each other. The two cathode anchor portions 133 are bent in different directions at the boundary between the cathode terminal portion 131 and the upright portion 133a and at the boundary between the upright portion 133a and the first extension portion 133b. That is, the first extension portions 133b of the two cathode anchor portions 133 are bent from the upper ends of the upright portion 133a and extend in directions away from each other in a direction (D2) perpendicular to the direction (D1) in which the anode lead 112 extends. The direction in which the first extension portions 133b extend is approximately parallel to the bottom surface 100b, and the angle they form may be in the range of -20° to 20°, for example.

[0056] 1, 2, 4, and 5, the second extension portions 133c of the two cathode anchor portions 133 each rise toward the upper surface 100t and are provided so as to sandwich the capacitor element 110 in a direction (D2) perpendicular to the direction (D1) in which the anode lead 112 extends. The two second extension portions 133c sandwich both side surfaces 110a of the capacitor element 110 above the cathode terminal portion 131. The direction in which the second extension portions 133c extend is approximately parallel to the direction perpendicular to the bottom surface 100b, and the angle formed therebetween may be in the range of −20° to 20°. The second extension portions 133c may be provided so that their upper ends reach a height corresponding to 10% to 60% of the height of the capacitor element 110, for example. The width of the second extending portion 133c is, for example, 5% to 20% of the height of the capacitor element 110.

[0057] 3, distance L1 from the surface of anode terminal 121 to the lower surface of extension portion 123b may be 50 μm or more (e.g., 75 μm or more or 100 μm or more). By setting distance L1 to 50 μm or more (e.g., 75 μm or more or 100 μm or more), it becomes easier to fill exterior resin 101 under extension portion 123b. Note that although the upper surface of extension portion 123b is located below the lower surface of capacitor element 110 in FIG. 3, extension portion 123b may be located higher as long as extension portion 123b does not interfere with capacitor element 110.

[0058] 4, distance L3 from the surface of cathode terminal 131 to the lower surface of first extension portion 133b may be 50 μm or more (e.g., 75 μm or more or 100 μm or more) or may be in a range of 50 μm to 500 μm (e.g., 75 μm to 200 μm). Distance L4 from the upper surface of first extension portion 133b to the lower surface of capacitor element 110 may be 50 μm or more (e.g., 75 μm or more or 100 μm or more) or may be in a range of 50 μm to 500 μm (e.g., 75 μm to 200 μm). Setting distances L3 and L4 to 50 μm or more (e.g., 75 μm or more or 100 μm or more) makes it easier to fill exterior resin 101 into the lower and upper parts of first extension portion 133b.

[0059] 4, the distance L2 between the second extension portion 133c and the side surface 110a of the capacitor element may be, for example, 80 μm or more, or may be in the range of 80 μm to 350 μm. When the distance L2 is in the above range, it is easy to prevent the capacitor element from being misaligned, and it is easy to arrange the capacitor element between two second extension portions. Furthermore, when the second extension portion and the capacitor element are electrically connected via a conductive adhesive layer, it is easy to provide the conductive adhesive layer.

[0060] The horizontal distance W1 (the distance along the direction D2) from the end side 121e to the tip of the extending portion 123b may be 50 μm or more (for example, 75 μm or more or 100 μm or more). By setting the horizontal distance W1 in this range, a high anchor effect can be obtained. Furthermore, from the viewpoint of shape stability and processability, the horizontal distance W1 may be 200 μm or more. The horizontal distance from the end side 131e of the first extending portion 133b to the end on the second extending portion 133c side may be greater than the horizontal distance W1.

[0061] The shapes of the anode lead terminal 120 and the cathode lead terminal 130 described above are merely examples and are not limited to the above shapes. For example, the anode lead terminal 120 may not include an anchor portion. Furthermore, the connection portion of the cathode lead terminal 130 does not have to be located at the position shown in the figure or have the shape shown in the figure, as long as it is electrically connected to the cathode portion 115 (cathode layer 117). The second extension portion 133c may be electrically connected to the cathode portion 115 (cathode layer 117), which will be described later. The second extension portion 133c may be in contact with the side surface 110a of the capacitor element 110 via a conductive adhesive layer.

[0062] 6, capacitor element 110 includes an anode portion 111 and a cathode portion 115. Anode portion 111 includes an anode body 113 having a dielectric layer 114 formed on its surface, and an anode lead 112. Cathode portion 115 includes an electrolyte layer 116 disposed so as to cover dielectric layer 114, and a cathode layer 117. Cathode layer 117 includes, for example, a carbon layer formed on electrolyte layer 116 and a metal particle layer formed on the carbon layer. The metal particle layer is a layer formed using, for example, a metal paste.

[0063] As described above, anode portion 111 of capacitor element 110 is electrically connected to anode lead terminal 120, and cathode portion 115 of capacitor element 110 is electrically connected to cathode lead terminal 130. When electrolytic capacitor 100 is mounted on a substrate or the like of an electronic device, anode terminal portion 121 and cathode terminal portion 131 may be mounted by soldering them together.

[0064] An example of a method for manufacturing the electrolytic capacitor 100 is described below. First, the capacitor element 110, the anode lead terminal 120, and the cathode lead terminal 130 are prepared. There are no particular limitations on the method for manufacturing the capacitor element 110, and it can be manufactured by a known method. The anode lead terminal 120 and the cathode lead terminal 130 can be formed by a known metal processing method.

[0065] Next, the anode lead 112 and the anode lead terminal 120 are connected, and the cathode layer 117 and the cathode lead terminal 130 are connected. The anode lead 112 and the anode lead terminal 120 can be connected by welding (e.g., laser welding) or the like. The cathode layer 117 and the cathode lead terminal 130 can be connected, for example, by the following method. First, a metal paste that becomes the conductive member 141 is applied to the surface of the cathode connecting portion 132 of the cathode lead terminal 130 and / or the surface of the cathode layer 117. Next, the cathode layer 117 and the cathode connecting portion 132 are bonded via the metal paste, and the metal paste is hardened to become the conductive member 141. In this way, the cathode layer 117 and the cathode lead terminal 130 can be connected. Furthermore, the second extension portion 133c and the side surface 110a of the capacitor element may be bonded using a metal paste.

[0066] Next, the capacitor element is sealed with the material of exterior resin 101 (e.g., molding resin). The sealing process can be performed by a known method. In this manner, electrolytic capacitor 100 can be manufactured. Note that other electrolytic capacitors of the present disclosure can also be manufactured by a similar manufacturing method. [Industrial Applicability]

[0067] The present disclosure can be used for electrolytic capacitors that require high reliability. [Explanation of symbols]

[0068] 100: Electrolytic capacitor 100b: Bottom 100t:Top surface 101: Exterior resin 110: Capacitor element 110a: Side 112: Anode lead 120: Anode lead terminal 121:Anode terminal part 121e: Edge 122: Wire connection 123: Anchor section 123a: Standing part 123b: Extension part 130: Cathode lead terminal 131: Cathode terminal part 131e: Edge 132: Cathode connection part 133: Anchor part 133a: Upright part 133b: First extending part 133c: Second extending part D1, D2: Directions

Claims

1. An electrolytic capacitor having a bottom surface and a top surface opposite to the bottom surface, a capacitor element including an anode lead; an anode lead terminal and a cathode lead terminal electrically connected to the capacitor element; an exterior resin disposed around the capacitor element, the cathode lead terminal includes a cathode terminal portion having an exposed surface exposed on the bottom surface, and two cathode anchor portions extending from the cathode terminal portion and embedded in the exterior resin, the cathode terminal portion has two end sides along the longitudinal direction of the anode lead, the two cathode anchor portions each include a cathode upright portion rising from the end edge of the cathode terminal portion toward the upper surface, a first extension portion extending from the cathode upright portion, and a second extension portion extending from the first extension portion, the first extension portion is bent from an upper end of the cathode standing portion, the second extension portion rises toward the upper surface, the first extension portion of one of the two cathode anchor portions and the first extension portion of the other of the two cathode anchor portions extend in directions away from each other, the second extension portion of one of the two cathode anchor portions and the second extension portion of the other of the two cathode anchor portions are arranged to sandwich the capacitor element in a direction perpendicular to a longitudinal direction of the anode lead.

2. The electrolytic capacitor according to claim 1 , wherein the entire surface of the first extension portion is in contact with the exterior resin.

3. 3. The electrolytic capacitor according to claim 1, wherein a region of the surface of the cathode terminal opposite to the exposed surface is in contact with the exterior resin.

4. the cathode lead terminal further includes a cathode connecting portion extending from the cathode terminal portion and embedded in the exterior resin, the cathode connection portion is in contact with the bottom surface of the capacitor element via a conductive adhesive layer; 4. The electrolytic capacitor according to claim 1, wherein the second extending portion is in contact with a side surface of the capacitor element via a conductive adhesive layer.

5. The electrolytic capacitor according to claim 4 , wherein the entire surface of the second extension portion is in contact with the exterior resin except for a region in contact with the conductive adhesive layer.

6. the anode lead terminal includes an anode terminal portion having an exposed surface exposed on the bottom surface, and an anode connection portion extending from the anode terminal portion and embedded in the exterior resin, 6. The electrolytic capacitor according to claim 1, wherein the anode connection portion is electrically connected to the anode lead.

7. 7. The electrolytic capacitor according to claim 6, wherein the anode connection portion rises from the anode terminal portion toward the upper surface and has a groove at its upper end for receiving the tip of the anode lead.

8. the anode terminal portion further includes two anode anchor portions extending from the anode terminal portion and embedded in the exterior resin, the anode terminal portion has two end sides along the longitudinal direction of the anode lead, 8. The electrolytic capacitor according to claim 6, wherein the two anode anchor portions each include an anode upright portion that stands from the end edge of the anode terminal portion toward the upper surface, and an anode extension portion that extends in a bent state from an upper end of the anode upright portion.

9. 9. The electrolytic capacitor according to claim 8, wherein the entire surface of the anode extension is in contact with the exterior resin.

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