Manufacturing method for stacked solid electrolytic capacitors

Abstract

Prevents defects caused by foreign matter resulting from molding and blasting processes. [Solution] A first terminal (20) of a stacked solid electrolytic capacitor (1) has a first through hole at a first side (44F) that is at least partially enclosed in an exterior resin body (40), and when viewed in a plane from a direction perpendicular to the bottom surface (45F), the first through hole is located only inside the outline of the exterior resin body.

Description

[Technical Field]

[0001] The present invention relates to a stacked solid electrolytic capacitor and a method for manufacturing the same. [Background technology]

[0002] A stacked solid electrolytic capacitor is known that uses capacitor elements each having a foil of a valve metal such as aluminum as an anode, a dielectric oxide film and a solid electrolyte layer formed to cover the valve metal, and a cathode formed thereon. The stacked solid electrolytic capacitor includes a stack of multiple such capacitor elements, an anode terminal connected to the anode of each capacitor element, a cathode terminal connected to the cathode of each solid capacitor element, and an exterior resin body.

[0003] A laminated solid electrolytic capacitor has also been proposed that includes an anode terminal or a cathode terminal with a through-hole (hole portion) that extends from the inside to the outside of the exterior resin body. In a laminated solid electrolytic capacitor with such a configuration, the terminal is fixed to the exterior resin body with the exterior resin body inserted into the through-hole, so that even if force is applied to the terminal, it is unlikely to peel off from the exterior resin body. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2024-142925 Summary of the Invention [Problem to be solved by the invention]

[0005] In such a stacked solid electrolytic capacitor, when the exterior resin body is formed by molding, burrs may be formed on the exterior of the exterior resin body. Such burrs may become foreign matter and cause problems such as damaging jigs used in manufacturing or the final product, so they are removed by blasting or the like.

[0006] In a laminated solid electrolytic capacitor having terminals with through holes extending from the inside to the outside of the exterior resin body as described above, burrs may also form inside the exterior through holes. Because the burrs inside the exterior through holes are attached to the surrounding anode terminals, etc., they are more difficult to remove by blasting than burrs in other areas. Therefore, increasing the intensity of the blasting can be considered as a means of ensuring their removal.

[0007] However, increasing the intensity of the blasting treatment can cause problems such as damage to the anode terminal, cathode terminal, or exterior resin body, or warping of the terminals, making subsequent processing difficult. In addition, there have been cases where blast particles become stuck inside the through-holes and detach during processing after the blasting treatment, or their adhesion becomes weak, resulting in problems similar to burrs. One aspect of the present invention aims to provide a stacked solid electrolytic capacitor that employs anode terminals or cathode terminals with through-holes, while preventing problems caused by foreign matter resulting from molding or blasting. [Means for solving the problem]

[0008] In order to solve the above problems, a stacked solid electrolytic capacitor according to one embodiment of the present disclosure includes a laminate in which a plurality of capacitor elements are stacked, an exterior resin body having a box-like outer shape and enclosing the laminate, and a first terminal electrically connected to either an anode or a cathode of the capacitor element inside the exterior resin body and extending to the outside from a first side surface of the exterior resin body, wherein the first terminal has a first through hole at least partially enclosed in the exterior resin body on the first side surface, and when the exterior resin body is viewed in a plane from a direction perpendicular to the bottom surface, the first through hole is located only inside the outline of the exterior resin body.

[0009] In order to solve the above problems, a method for manufacturing a stacked solid electrolytic capacitor according to one aspect of the present disclosure includes: a laminate in which a plurality of capacitor elements are stacked; an exterior resin body having a box-like outer shape and enclosing the laminate; and a first terminal electrically connected to either an anode or a cathode of the capacitor element inside the exterior resin body and extending to the outside from a first side surface of the exterior resin body, the first terminal having a first through-hole at least partially enclosed within the exterior resin body on the first side surface, and a first terminal extending from a direction perpendicular to the bottom surface of the exterior resin body. A method for manufacturing a stacked solid electrolytic capacitor in which, when viewed from above, the first through hole is located only inside the outline of the exterior resin body, the method comprising: a molding process in which resin is injected between a first mold form on the bottom side and a second mold form on the top side opposite the bottom side to form the exterior resin body; and a blasting process in which burrs produced by the molding process and adhering to the exterior resin body near the boundary between the first mold form and the second mold form are removed by projecting blast particles onto the exterior resin body from at least one direction of the bottom side and the top side. [Effects of the Invention]

[0010] According to one aspect of the present disclosure, a stacked solid electrolytic capacitor can be realized that employs an anode terminal or a cathode terminal with a through hole, while being able to prevent defects caused by foreign matter resulting from molding or blasting. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a perspective view showing the appearance of a stacked solid electrolytic capacitor according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a front view of the stacked solid electrolytic capacitor. [Figure 3] 1 is a diagram illustrating a method for manufacturing the stacked solid electrolytic capacitor, showing a patterned metal plate for forming a lead frame. [Figure 4]1 is a diagram illustrating a method for manufacturing the stacked solid electrolytic capacitor, showing a state in which a stack is mounted on an anode terminal and a cathode terminal. [Figure 5] 1 is a diagram illustrating a method for manufacturing the stacked solid electrolytic capacitor, showing a state in which an exterior resin body has been molded. [Figure 6] FIG. 2 is a partially enlarged front view of the stacked solid electrolytic capacitor. [Figure 7] 3A to 3C are partially enlarged plan views of the stacked solid electrolytic capacitor during the manufacturing process. [Figure 8] 3A to 3C are partially enlarged bottom views of the stacked solid electrolytic capacitor during the manufacturing process. [Figure 9] FIG. 4 is a partially enlarged front view of a stacked solid electrolytic capacitor according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0012] [Embodiment 1] A stacked solid electrolytic capacitor according to an embodiment of the present disclosure is described in detail below. The stacked solid electrolytic capacitor is a capacitor component including a laminate in which a plurality of capacitor elements, each of which uses a solid electrolyte such as a conductive polymer, are stacked.

[0013] <External appearance and internal structure of multilayer solid electrolytic capacitor 1> FIG. 1 is a perspective view showing the appearance of a stacked solid electrolytic capacitor 1 according to Embodiment 1. FIG. 2 is a front view of the stacked solid electrolytic capacitor 1. The stacked solid electrolytic capacitor 1 includes an anode terminal 10, a cathode terminal 20, and an exterior resin body 40. The anode terminal 10 is a terminal electrically connected to each anode 31 of a plurality of capacitor elements 30 (see FIG. 4). The cathode terminal 20 is a terminal electrically connected to each cathode 32 of the plurality of capacitor elements 30. Either the anode terminal 10 or the cathode terminal 20 corresponds to a first terminal, and the other corresponds to a second terminal.

[0014] The exterior resin body 40 encloses and seals a laminate 30S (see FIG. 4) in which a plurality of capacitor elements 30 are stacked. The exterior resin body 40 has a box-like outer shape. The exterior resin body 40 is substantially rectangular. A bottom surface 45F and a top surface 46F of the substantially rectangular exterior resin body 40 are substantially rectangular. The bottom surface 45F and the top surface 46F are surfaces that face each other. The bottom surface 45F is the surface that faces the circuit board when the multilayer solid electrolytic capacitor 1 is mounted on the circuit board as an electronic component.

[0015] As shown in each figure, including FIG. 1 , in the description of the present application, the direction perpendicular to the principal surface of the bottom surface 45F and the principal surface of the top surface 46F of the exterior resin body 40 is referred to as the Z-axis. The top surface 46F is located on the positive side of the Z-axis relative to the bottom surface 45F. The positive side of the Z-axis direction may be referred to as the upper side, and the negative side may be referred to as the lower side. The Z-axis direction is also referred to as the up-down direction. The X-axis and Y-axis are parallel to the principal surface of the bottom surface 45F and the principal surface of the top surface 46F, respectively. The X-axis and Y-axis are parallel to the short and long sides of the approximately rectangular bottom surface 45F and the top surface 46F, respectively. A view of the stacked solid electrolytic capacitor 1 viewed in the negative direction of the X-axis is referred to as a front view. A view of the stacked solid electrolytic capacitor 1 viewed in the negative direction of the Z-axis is referred to as a plan view, and a view viewed in the positive direction is referred to as a bottom view.

[0016] The height (vertical length) of the substantially rectangular exterior resin body 40 is smaller than the lengths of the long sides of the substantially rectangular bottom surface 45F and top surface 46F. That is, the length of the substantially rectangular exterior resin body 40 in the Z-axis direction is smaller than the length of the Y-axis direction. Therefore, the Y-axis direction of the multilayer solid electrolytic capacitor 1 is also referred to as the longitudinal direction, and the X-axis direction is also referred to as the width direction. Furthermore, the height of the substantially rectangular exterior resin body 40 is usually smaller than the lengths of the short sides of the substantially rectangular bottom surface 45F and top surface 46F.

[0017] The exterior resin body 40 is composed of an upper resin body 40A and a lower resin body 40B. The upper resin body 40A occupies approximately the upper half of the exterior resin body 40, and the lower resin body 40B occupies approximately the lower half of the exterior resin body 40. A boundary line 40C is formed on the surface of the exterior resin body 40 at the boundary between the upper resin body 40A and the lower resin body 40B. The boundary line 40C is formed approximately at the center in the Z-axis direction of each of the four side surfaces 41F to 44F of the exterior resin body 40. The boundary line 40C runs around the surface of the exterior resin body 40. Note that the exterior resin body 40 itself is a single resin part, and the boundary line 40C simply divides the upper resin body 40A from the lower resin body 40B.

[0018] Above and below boundary line 40C, the cross section perpendicular to the Z axis of upper resin body 40A is slightly larger than that of lower resin body 40B. That is, above and below boundary line 40C, the length in the Y axis direction of upper resin body 40A is slightly larger than that of lower resin body 40B. Therefore, as shown in FIG. 2, on side surfaces 43F and 44F of exterior resin body 40, whose main surfaces are substantially perpendicular to the Y axis, a small step occurs above and below boundary line 40C. A gate mark 40G, which will be described in detail later, is located near the center of one of side surfaces 41F and 42F that are substantially perpendicular to the X axis. Gate mark 40G has an elongated, substantially rectangular shape extending in the Y axis direction. The long side of gate mark 40G on the positive side (upper side) of the Z axis overlaps boundary line 40C.

[0019] The capacitor element 30 constituting the laminate 30S enclosed in the exterior resin body 40 is a known technique and will only be briefly described. One end of a foil or thin plate of aluminum or other valve metal with a dielectric oxide film formed on its surface serves as the anode 31. Furthermore, a solid electrolyte made of a conductive polymer or the like is formed on the dielectric oxide film, and a conductive layer serving as the cathode 32 is formed on the solid electrolyte made of a conductive paste or the like. An insulating resist tape is disposed between the anode 31 and the cathode 32 on the surface of the capacitor element 30.

[0020] A plurality of capacitor elements 30 are stacked so that the anodes 31 of the capacitor elements 30 overlap each other and so that the cathodes 32 of the capacitor elements 30 overlap each other, thereby forming a laminate 30S. As shown in Fig. 4, the laminate 30S is mounted on the anode terminal 10 and the cathode terminal 20 so as to straddle these terminals.

[0021] Therefore, a flat first region 11 is provided at the end of anode terminal 10 facing the interior of exterior resin body 40, on which anode 31 of stacked capacitor elements 30 is mounted. Furthermore, a flat first region 21 is provided at the end of cathode terminal 20 facing the interior of exterior resin body 40, on which cathode 32 of stacked capacitor elements 30 is mounted. First region 11 of anode terminal 10 and first region 21 of cathode terminal 20 each constitute a plane (XY plane) substantially perpendicular to the Z axis.

[0022] The metal plate 60 is bent to form a second region 12 that continues from the first region 11 in the anode terminal 10 (FIGS. 3 and 4). The second region 12 is substantially perpendicular to the Y-axis. At the stage of the manufacturing process shown in FIGS. 3 and 4, the metal plate 60 is further bent from the second region 12, so that the portion that continues from the second region 12 is substantially perpendicular to the Z-axis. Of the portion that continues from the second region 12, the region that is closest to the second region 12 becomes the third region 13, which will be described later (FIG. 2).

[0023] The metal plate 60 is further bent to form a third region 13 that continues from the second region 12 of the anode terminal 10. The third region 13 is approximately perpendicular to the Z axis. As described above, the metal plate 60 is bent from the second region 12 so as to be approximately perpendicular to the Z axis, and then the metal plate 60 is further bent so as to be approximately perpendicular to the Y axis, thereby forming the third region 13 as shown in FIG. 2. A through hole 10H is provided in the center of the anode terminal 10 in the X axis direction (width direction) from the region corresponding to the third region 13 to the second region 12 (FIG. 3). When the portion of the patterned metal plate 60 corresponding to the anode terminal 10 is in an unbent flat state, the opening shape of the through hole 10H may be, for example, square, rectangular, circular, or the like.

[0024] In the cathode terminal 20, the metal plate 60 is also bent to form a second region 22 that continues from the first region 21. The second region 22 is substantially perpendicular to the Y axis. At the stage of the manufacturing process shown in FIGS. 3 and 4, the metal plate 60 is further bent from the second region 22, so that the portion that continues from the second region 22 is substantially perpendicular to the Z axis. Of the portion that continues from the second region 22, the region that is closest to the second region 22 becomes the third region 23, which will be described later (FIGS. 2, 6, and 8).

[0025] The metal plate 60 is bent to form a third region 23 that continues from the second region 22 in the cathode terminal 20. The third region 23 is approximately perpendicular to the Z axis. As described above, the metal plate 60 is bent from the second region 22 so as to be approximately perpendicular to the Z axis, and then the metal plate 60 is further bent so as to be approximately perpendicular to the Y axis, thereby forming the third region 23 as shown in FIG. 2. The cathode terminal 20 has a through hole 20H formed in the center of the cathode terminal 20 in the X-axis direction (width direction) from the region corresponding to the third region 23 to the second region 22 (FIGS. 3, 6, and 8). When the portion of the patterned metal plate 60 corresponding to the cathode terminal 20 is in an unbent flat state, the opening shape of the through hole 20H may be, for example, square, rectangular, circular, or the like.

[0026] Furthermore, a pair of sixth regions 26 are provided in the cathode terminal 20 to cover at least a portion of the side surface of the laminate 30S (FIG. 4). The sixth regions 26 are formed integrally with the first region 21 by bending both side portions of the first region 21 of the patterned metal plate 60 in the X-axis direction (width direction). Each sixth region 26 is configured on a plane (YZ plane) substantially perpendicular to the X-axis. One of the through hole 10H provided in the anode terminal 10 and the through hole 20H provided in the cathode terminal 20 corresponds to the first through hole, and the other corresponds to the second through hole.

[0027] 3, the laminate 30S is mounted in the state shown in FIG. 4 on the portions of the patterned metal plate 60 corresponding to the respective stacked solid electrolytic capacitors 1. Here, the cathode 32 of each capacitor element 30 is fixed and electrically connected to the first region 21 or the sixth region 26 of the cathode terminal 20 using a conductive adhesive or other known method. The anode 31 of each capacitor element 30 is fixed and electrically connected to the first region 11 of the anode terminal 10 by welding or other known method.

[0028] A portion of anode terminal 10 is enclosed within exterior resin body 40, and the other portion is exposed from exterior resin body 40. A portion of cathode terminal 20 is enclosed within exterior resin body 40, and the other portion is exposed from exterior resin body 40.

[0029] In the third region 13 of the anode terminal 10, the anode terminal 10 is extended to the outside from one of the side surfaces 43F, 44F of the exterior resin body 40, the main surface of which is substantially perpendicular to the Y axis. In the third region 23 of the cathode terminal 20, the cathode terminal 20 is extended to the outside from the other of the side surfaces 43F, 44F of the exterior resin body 40, the main surface of which is substantially perpendicular to the Y axis. The side surface from which the anode terminal 10 is extended and the side surface from which the cathode terminal 20 is extended are the side surfaces 43F, 44F that face each other. One of the side surfaces 43F, 44F corresponds to the first side surface, and the other corresponds to the second side surface.

[0030] 1 and 2, the anode terminal 10 extends from the side surface 43F on the negative side in the Y-axis direction, and the cathode terminal 20 extends from the side surface 44F on the positive side in the Y-axis direction. Unless otherwise specified, the following description will focus on the side surfaces approximately perpendicular to the Y-axis from which the anode terminal 10 and the cathode terminal 20 extend in the case of the stacked solid electrolytic capacitor 1 according to embodiment 1 shown in FIGS.

[0031] 1 and 2, the upper surface of the anode terminal 10 at the extended position substantially coincides with the boundary line 40C. That is, the anode terminal 10 is extended from the lower resin body 40B of the exterior resin body 40. The anode terminal 10 is extended in the third region 13 from approximately the center of the exterior resin body 40 in the Z axis direction, and is then bent toward the negative side (downward) in the Z axis direction so as to fit along the extended side surface 43F. The anode terminal 10 is further bent when it reaches the bottom surface 45F so as to fit along the bottom surface 45F.

[0032] The region of the anode terminal 10 continuing from the third region 13, from when it is bent toward the negative side in the Z axis direction (downward) to when it is further bent along the bottom surface 45F, is referred to as the fourth region 14. The region of the anode terminal 10 continuing along the bottom surface 45F, from the fourth region 14, is referred to as the fifth region 15. The fourth region 14 is approximately perpendicular to the Y axis. The fifth region 15 is a portion that is approximately parallel to the main surface of the top surface 46F or the main surface of the bottom surface 45F (approximately parallel to the XY plane). Note that the anode terminal 10 pulled out from the lower resin body 40B may be bent at a substantially right angle at the tip in the Y axis direction toward the negative side in the Z axis direction (downward) to form the fifth region 15, and then bent along the side surface 43F to form the fourth region 14.

[0033] At the position where cathode terminal 20 is pulled out, the upper surface of cathode terminal 20 substantially coincides with boundary line 40C. That is, cathode terminal 20 is pulled out from lower resin body 40B of exterior resin body 40. In this manner, cathode terminal 20 is pulled out in third region 23 from approximately the center in the Z axis direction of exterior resin body 40, and is further bent toward the negative side in the Z axis direction (downward) to fit along side surface 44F from which it is pulled out. Furthermore, cathode terminal 20 is bent when it reaches bottom surface 45F to fit along bottom surface 45F.

[0034] The region of cathode terminal 20 continuing from third region 23, from when it is bent toward the Z-axis negative side (downward) until it is further bent along bottom surface 45F, is referred to as fourth region 24. The region continuing from fourth region 24 along bottom surface 45F is referred to as fifth region 25 of cathode terminal 20. Fourth region 24 is approximately perpendicular to the Y-axis. Fifth region 25 is a portion that is approximately parallel to the main surface of top surface 46F or the main surface of bottom surface 45F (approximately parallel to the XY plane). Note that cathode terminal 20 extended from lower resin body 40B may first have its tip in the Y-axis direction bent toward the Z-axis negative side (downward) at an approximately right angle to form fifth region 25, and then bent along side surface 44F to form fourth region 24.

[0035] A protruding portion 453 that protrudes further toward the negative side in the Z axis direction than the remaining portion is provided in the center of the bottom surface 45F of the exterior resin body 40 in the Y axis direction. Therefore, step portions 451 and 452 that are recessed further toward the positive side in the Z axis direction than protruding portion 453 are formed on the bottom surface 45F. The fifth region 15 of the anode terminal 10 is disposed in step portion 451, and is disposed such that a portion of the fifth region 15 is positioned slightly to the negative side in the Z axis direction (lower) than the position of protruding portion 453 on the bottom surface 45F.

[0036] Similarly, fifth region 25 of cathode terminal 20 is disposed in step portion 452, with a portion of it positioned slightly to the negative side in the Z-axis direction (lower side) than the position of bottom surface 45F of protrusion 453. In this way, when stacked solid electrolytic capacitor 1 is mounted on the above-described circuit board, fifth region 15 of anode terminal 10 and fifth region 25 of cathode terminal 20 can each be connected to an electrode pad provided on the circuit board.

[0037] <Method of Manufacturing Stacked Solid Electrolytic Capacitor 1> Next, a method for manufacturing the stacked solid electrolytic capacitor 1 will be described with reference to FIGS.

[0038] The anode terminal 10 and the cathode terminal 20 of the multilayer solid electrolytic capacitor 1 are formed as a lead frame. Therefore, a metal plate 60 is prepared on which wiring patterns that will form the anode terminals 10 and the cathode terminals 20 of a large number of the multilayer solid electrolytic capacitors 1 are patterned. The prepared metal plate 60 is then folded to form the first regions 11 and 21, the second regions 12 and 22, and the sixth region 26 of the anode terminals 10 and the cathode terminals 20. FIG. 3 shows the folded patterned metal plate 60 used to form such a lead frame. A multilayer body 30S is then mounted on the metal plate 60. FIG. 4 is a plan view showing the portion of the patterned metal plate 60 in FIG. 3 that corresponds to one multilayer solid electrolytic capacitor 1, and also shows the multilayer body 30S mounted on the anode terminal 10 and the cathode terminal 20.

[0039] Next, in the molding process, the exterior resin body 40 of each stacked solid electrolytic capacitor 1 is molded to enclose each laminate 30S. Figure 5 is a diagram illustrating the point in the manufacturing process when each exterior resin body 40 is formed after the laminate 30S of each stacked solid electrolytic capacitor 1 is mounted on the patterned metal plate 60 in the state shown in Figure 3.

[0040] The exterior resin body 40 is molded by injecting and curing resin between a first mold form on the bottom surface 45F side and a second mold form on the top surface 46F side. The first mold form on the bottom surface 45F side is also referred to as the lower mold form, and the second mold form on the top surface 46F side is also referred to as the upper mold form. The first mold form and the second mold form together are also referred to as the upper and lower mold forms.

[0041] The runner 70 is a flow path for the resin before hardening that is poured between the upper and lower molds. The gate connection portion 71 of the runner 70 is a portion that connects to a gate, which is an injection port for the resin, provided between the upper and lower molds. The gate mark 40G on the exterior resin body 40 shown in FIGS. 1 and 2 is a mark of such a gate. In the molding process, the laminate 30S, which is mounted on a lead frame and fixed and electrically connected, is placed in the upper and lower molds. Thereafter, resin is injected into the upper and lower molds through the runner 70. After the resin hardens, the exterior resin body 40 and the runner 70 are removed from the upper and lower molds, and the exterior resin body 40 and the gate connection portion 71 are separated. At this time, the gate mark 40G is formed in the exterior resin body 40.

[0042] The boundary line 40C in exterior resin body 40 corresponds to the boundary between the upper and lower mold frames. During molding, anode terminal 10 and cathode terminal 20 are sandwiched between the upper and lower mold frames. Therefore, as shown in FIGS. 1 and 2 , anode terminal 10 and cathode terminal 20 contact boundary line 40C of exterior resin body 40.

[0043] Although not shown in FIG. 5, burrs, which are hardened resin that protrudes from the boundaries between the upper and lower molds, are formed on exterior resin body 40 after molding. That is, burrs that protrude along boundary line 40C are formed on side surfaces 41F to 44F of exterior resin body 40 after molding. Such burrs need to be removed before multilayer solid electrolytic capacitor 1 is made into a final product. Therefore, a process for removing the burrs is carried out after molding.

[0044] From the viewpoint of productivity, it is efficient to perform the process of removing such burrs by blasting. Blasting is a process in which solid particles, also known as blast particles, mixed with a fluid are sprayed onto an object to perform some kind of processing. In this embodiment, the blasting process involves spraying blast particles in a blasting process to remove burrs protruding from the side surfaces 41F to 44F. The blast particles are sprayed from the Z-axis direction (vertical direction), and in particular, to prevent the upper resin body 40A or the lower resin body 40B from blocking the burrs and leaving unprocessed burrs, it is preferable to project the blast particles from both the vertical and vertical directions at an angle relative to the Z-axis direction (vertical direction).

[0045] After the blasting treatment, portions of the patterned metal plate 60 shown in FIG. 5 that will become the anode terminal 10 and the cathode terminal 20 are cut off. The portion exposed to the outside of the exterior resin body 40 is then folded twice to form the anode terminal 10, thereby defining a third region 13, a fourth region 14, and a fifth region. Similarly, the portion exposed to the outside of the exterior resin body 40 is folded twice to form the cathode terminal 20, thereby defining a third region 23, a fourth region 24, and a fifth region 25. In this manner, the stacked solid electrolytic capacitor 1 shown in FIGS. 1 and 2 is manufactured.

[0046] Below, details of through-hole 20H of cathode terminal 20 will be described with reference to Fig. 6, but the same applies to anode terminal 10. Fig. 6 is a partially enlarged front view of stacked solid electrolytic capacitor 1, showing an enlarged view of the area enclosed by frame p6 in Fig. 2. That is, Fig. 6 is a front view of stacked solid electrolytic capacitor 1, showing an enlarged view of the vicinity of the position where cathode terminal 20 is pulled out. In Fig. 6, the position of cathode terminal 20 inside exterior resin body 40 is indicated by a dotted line.

[0047] The fourth region 24 of the cathode terminal 20, which is disposed outside the exterior resin body 40, is a portion that is substantially perpendicular to the Y axis and that extends along the side surface 44F. The second region 22 of the cathode terminal 20, which is disposed inside the exterior resin body 40, is a portion that is substantially perpendicular to the Y axis and that extends along the side surface 44F. The third region 23, which is located between the second region 22 and the fourth region 24, is located at a portion where the cathode terminal 20 is drawn out from the exterior resin body 40. The third region 23 is substantially perpendicular to the Z axis.

[0048] Cathode terminal 20 has a through hole 20H extending from second region 22 to third region 23. The extent of through hole 20H in cathode terminal 20 is also indicated by a dotted line in Figure 6. As such, cathode terminal 20 has through hole 20H that is at least partially enclosed in exterior resin body 40 on side surface 44F of exterior resin body 40. In other words, at least a portion of through hole 20H is enclosed in the resin that constitutes exterior resin body 40.

[0049] Through hole 20H provided in cathode terminal 20 is located only inside the outline of exterior resin body 40 when exterior resin body 40 is viewed from above in a direction perpendicular to the main surface of bottom surface 45F, i.e., in the Z-axis direction. In other words, through hole 20H is located in a position that will not be exposed to blast particles projected from the positive side to the negative side in the Z-axis direction during the blasting process. To this extent, when third region 23 of cathode terminal 20 is viewed in the positive Z-axis direction, i.e., when third region 23 is viewed from the bottom surface 45F side, part of through hole 20H may be exposed from exterior resin body 40. This situation is shown in FIGS. 6 to 8.

[0050] According to the first embodiment, the cathode terminal 20 is enclosed in the exterior resin body 40 such that at least a portion of the through hole 20H of the cathode terminal 20 is enclosed in the resin that constitutes the exterior resin body 40. Therefore, even if an external force is applied to an exposed portion of the cathode terminal 20, the force is unlikely to be applied to a portion inside the exterior resin body 40. In other words, the resin that penetrates the through hole 20H acts as an anchor, making it difficult for the external force to be transmitted to the cathode terminal 20 inside the exterior resin body 40. This maintains close contact between the exterior resin body 40 and the cathode terminal 20, thereby preventing the cathode terminal 20 from peeling off from the exterior resin body 40. This also maintains the sealing of the laminate 30S, thereby preventing deterioration of the characteristics of the multilayer solid electrolytic capacitor 1.

[0051] To ensure that the resin passing through through hole 20H fully exerts its anchoring effect, the width (length in the X-axis direction) of the portion of the opening of through hole 20H provided in cathode terminal 20 made of a thin metal plate that is enclosed in exterior resin body 40 is preferably 20% or more of the width (length in the X-axis direction) of cathode terminal 20, and the sum of the depth (length in the Y-axis direction) and height (length in the Z-axis direction) of the enclosed portion is preferably 25% or more of the height (length in the Z-axis direction) of exterior resin body 40. In this case, it is preferable that the width of cathode terminal 20 in third region 23 is approximately 0.5 to 3 mm, and the height of exterior resin body 40 is approximately 1 mm to 3 mm. Note that the width, depth, and height of the opening of through hole 20H are evaluated along the surface of the metal plate that constitutes cathode terminal 20.

[0052] <Effect, etc.> In the stacked solid electrolytic capacitor according to the first embodiment, the through holes 10H, 20H provided in the anode terminal 10 and the cathode terminal 20 are located inside the contour of the exterior resin body 40. Therefore, even if the exterior resin is enclosed inside the through holes 10H, 20H during the molding process, the through holes are located inside the contour of the exterior resin body 40 and do not become burrs that need to be removed as in the conventional case.

[0053] Furthermore, when viewed from above in the positive direction of the Z axis of the exterior resin body 40, the through holes 10H and 20H are hidden by the upper resin body 40A. Therefore, when blast particles are projected from above in the Z axis direction, the through holes 10H and 20H are not exposed to the blast particles, and the blast particles do not clog the through holes 10H and 20H. On the other hand, when blast particles are projected from below in the Z axis direction, the through holes 10H and 20H may be exposed to the blast particles because of their exposed portions. However, clogging of the through holes with blast particles occurs because the diameter of the exposed portions of the through holes is close to the diameter of the blast particles. Although the through holes 10H and 20H are exposed from the exterior resin body 40, the exposed portions are located between the contours of the lower resin body 40B and the upper resin body 40A, so the diameter of the exposed portions can be made sufficiently smaller than the diameter of the blast particles. Therefore, even when blast particles are projected from below in the Z-axis direction, the through holes 10H and 20H are not clogged with the blast particles.

[0054] Therefore, in the stacked solid electrolytic capacitor according to embodiment 1, the formation of burrs inside the through holes 10H, 20H can be suppressed, the intensity of the blasting process can be reduced, and clogging of the through holes 10H, 20H with blast particles can be suppressed, thereby preventing problems caused by foreign matter resulting from molding or the blasting process.

[0055] [Embodiment 2] The stacked solid electrolytic capacitor 1B according to Embodiment 2 is similar to the stacked solid electrolytic capacitor 1 according to Embodiment 1, except that the positions of the through holes 10H provided in the anode terminal 10 and the through holes 20H provided in the cathode terminal 20 are different from those in Embodiment 1. FIG. 9 is a partially enlarged front view of the stacked solid electrolytic capacitor 1B according to Embodiment 2, and corresponds to FIG. 6 for explaining the stacked solid electrolytic capacitor 1 in Embodiment 1. Below, the cathode terminal 20 will be described with reference to FIG. 9, but the same applies to the anode terminal 10.

[0056] Compared to the laminated solid electrolytic capacitor 1 according to the first embodiment, the through hole 20H provided in the cathode terminal 20 of the laminated solid electrolytic capacitor 1B according to the second embodiment is located closer to the inside of the exterior resin body 40 in the third region 23. That is, in FIG. 9 , the through hole 20H provided in the cathode terminal 20 is located closer to the negative side in the Y-axis direction. In other words, the entire through hole 20H is enclosed within the exterior resin body 40. More specifically, the entire through hole 20H is enclosed within the lower resin body 40B of the exterior resin body 40.

[0057] In the stacked solid electrolytic capacitor 1B according to the second embodiment, burrs are not formed in the through holes 10H, 20H formed in the anode terminal 10 and the cathode terminal 20 during the molding process. Furthermore, the through holes 10H, 20H are not exposed to blast particles during the blasting process. Therefore, in the second embodiment as well, problems caused by foreign matter resulting from the molding and blasting processes can be prevented.

[0058] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Examples obtained by appropriately combining the technical means disclosed in the embodiments are also included in the technical scope of the present invention. Furthermore, although the examples shown in the above embodiments illustrate examples in which through holes are provided in both anode terminal 10 and cathode terminal 20, a through hole may be provided in only one of them. [Explanation of symbols]

[0059] 1. 1B Stacked Solid Electrolytic Capacitor 10 Anode terminal (1st terminal, 2nd terminal) 10H Through hole (first through hole, second through hole) 20 Cathode terminal (1st terminal, 2nd terminal) 20H Through hole (first through hole, second through hole) 30S laminate 30 Capacitor element 31 Anode 32 Cathode 40 Exterior resin body 40C border 41F, 42F side 43F, 44F Side (1st side, 2nd side) 45F bottom 46F top

Claims

[Claim 1] a laminate in which a plurality of capacitor elements are stacked; an exterior resin body having a box-like outer shape and enclosing the laminate; a first terminal electrically connected to either the anode or the cathode of the capacitor element inside the exterior resin body and drawn out from a first side surface of the exterior resin body, the first terminal has a first through hole at the first side surface, at least a portion of which is enclosed in the exterior resin body; when the exterior resin body is viewed in a plan view from a direction perpendicular to a bottom surface thereof, the first through-hole is located only inside an outline of the exterior resin body; the exterior resin body has an integrally formed upper resin body on the top surface side and a lower resin body on the bottom surface side having a smaller outline than the upper resin body, a method for manufacturing a stacked solid electrolytic capacitor, wherein the first terminal is drawn out from the lower resin body on the first side surface of the exterior resin body, a molding process of injecting resin between a first mold form on the bottom surface side for forming the lower resin body and a second mold form on the top surface side facing the bottom surface for forming the upper resin body, thereby molding the exterior resin body; a blasting process for removing burrs that have formed in the molding process near the boundary between the first mold form and the second mold form and that adhere to the exterior resin body by projecting blast particles onto the exterior resin body from the top surface side.

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