Capacitor module

Abstract

To provide a capacitor module in which, when capacitor elements are electrically connected to each other via a plurality of connection terminals, it is possible to easily achieve electrical connection between the connection terminals.SOLUTION: In a capacitor module 1, a first main connection terminal 21a is provided with a first through hole 31a, and a dimension P1 in a first direction D1 of the first through hole 31a is smaller than the maximum distance Q1 in the first direction D1 between a surface 22aa of a first sub-connection terminal 22a opposite to a second sub-connection terminal 22b and a surface 22ba of the second sub-connection terminal 22b opposite to the first sub-connection terminal 22a, and the first sub-connection terminal 22a and the second sub-connection terminal 22b pass through the first through hole 31a with one ends in contact with each other and the other ends separated from each other.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a capacitor module. [Background technology]

[0002] Patent Document 1 discloses a capacitor module comprising: a plurality of capacitors each having a first electrode and a second electrode facing each other, and a side surface connecting the first electrode and the second electrode and having a pair of flat portions facing each other and a pair of curved portions connecting one of the flat portions to the other of the flat portions, the plurality of capacitors being arranged in a row so that the flat portions face each other; at least one metal plate arranged somewhere between the flat portions of each of the adjacent capacitors and in contact with the first electrode of at least one of the adjacent capacitors; a first bus bar electrically connected to the at least one metal plate; and a second bus bar electrically connected to each of the second electrodes, wherein each of the first electrodes of the plurality of capacitors is electrically connected to the at least one metal plate.

[0003] Patent Document 2 discloses a capacitor comprising a capacitor element, a first electrode plate connected to one electrode portion of the capacitor element via a first lead terminal, and a second electrode plate connected to the other electrode portion of the capacitor element via a second lead terminal, the first and second electrode plates being overlapped with a sheet-like insulator interposed therebetween and the second electrode plate being positioned between the first electrode plate and the capacitor element, the second electrode plate having an opening formed therein through which the first lead terminal is inserted, the first electrode plate having a recess recessed into the opening and used for connection to the first lead terminal, and a through hole formed in a step between the recess and other portions for partially separating the recess from other portions, the insulator having a plurality of slits formed therein and extending outward from a portion facing the recess, and the insulator located between the slits being folded towards the second electrode plate and interposed between the recess and the inner peripheral edge of the opening. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2021 / 241320 [Patent Document 2] JP 2015-15380 A Summary of the Invention [Problem to be solved by the invention]

[0005] In a capacitor module including a plurality of capacitor elements, a combination of a plurality of connection terminals may be used to electrically connect the capacitor elements to each other.

[0006] For example, in the capacitor module described in Patent Document 1, a metal plate connected to a first electrode of a capacitor and a first bus bar connected to the metal plate are combined to electrically connect capacitors to each other, as shown in, for example, Figure 2 of Patent Document 1. However, in the capacitor module described in Patent Document 1, as shown in, for example, Figure 2 of Patent Document 1, the metal plate extends from one end to the other end of the capacitor, so that the current path from the first electrode of the capacitor through the metal plate to the first bus bar is long, which tends to increase the equivalent series inductance (ESL).

[0007] On the other hand, in the capacitor described in Patent Document 2, in order to electrically connect the capacitor elements to each other, a lead terminal connected to the electrode portion of the capacitor element and an electrode plate connected to the lead terminal are combined and used, as shown in Figure 1 etc. of Patent Document 2. In the capacitor described in Patent Document 2, as shown in Figure 1 etc. of Patent Document 2, the current path from the electrode portion of the capacitor element through the lead terminal to the electrode plate is short, so it is considered that the equivalent series inductance is less likely to become large compared to the capacitor module described in Patent Document 1.

[0008] On the other hand, in the capacitor described in Patent Document 2, as shown in FIG. 1 of Patent Document 2, the lead terminal is passed through a connection hole of the electrode plate to connect the lead terminal and the electrode plate. However, in the capacitor described in Patent Document 2, if the sizes of the lead terminal and the connection hole do not match exactly, the connection between the lead terminal and the electrode plate will be insufficient. Furthermore, in the capacitor described in Patent Document 2, when connecting the lead terminal and the electrode plate, not only the sizes but also the positions of the lead terminal and the connection hole must be matched exactly. For example, in the capacitor described in Patent Document 2, even if the sizes of the lead terminal and the connection hole are matched, if their positions are misaligned, the lead wire cannot be passed through the connection hole.

[0009] As described above, in the capacitor described in Patent Document 2, when the capacitor elements are electrically connected to each other by the lead terminals and the electrode plates, there is room for improvement in terms of easily realizing electrical connection between the lead terminals and the electrode plates.

[0010] In the capacitor module described in Patent Document 1, the metal plate and the first bus bar are connected by passing the bus bar contact portion of the metal plate through a hole in the first bus bar. As a result, as with the capacitor described in Patent Document 2, there is room for improvement in terms of easily achieving electrical connection between the metal plate and the first bus bar.

[0011] The present invention has been made to solve the above problems, and aims to provide a capacitor module in which when capacitor elements are electrically connected to each other by a plurality of connection terminals, electrical connection between the connection terminals can be easily achieved. [Means for solving the problem]

[0012] The capacitor module of the present invention comprises an element body, a plurality of capacitor elements, each of which has a first external electrode provided on one end face of the element body and a second external electrode provided on the other end face facing the one end face of the element body in a first direction, and a plurality of connection terminals electrically connected to the plurality of capacitor elements, the plurality of capacitor elements including a first capacitor element and a second capacitor element adjacent in the first direction such that the first external electrodes having the same polarity face each other and are spaced apart from each other, and the plurality of connection terminals include a first main connection terminal electrically connected to the first external electrodes of the first capacitor element and the second capacitor element at a position spaced from the first capacitor element and the second capacitor element, and a second connection terminal electrically connected to the first main connection terminal at one end side. the first sub-connection terminal has one end side electrically connected to the first external electrode of the first capacitor element, and the other end side of the second sub-connection terminal has one end side electrically connected to the first main connection terminal and the other end side electrically connected to the first external electrode of the second capacitor element, wherein the first main connection terminal has a first through hole, a dimension of the first through hole in the first direction is smaller than a maximum distance in the first direction between a surface of the first sub-connection terminal opposite to the second sub-connection terminal and a surface of the second sub-connection terminal opposite to the first sub-connection terminal, and the first sub-connection terminal and the second sub-connection terminal pass through the first through hole with the one ends in contact with each other and the other ends separated from each other. Effect of the Invention

[0013] According to the present invention, it is possible to provide a capacitor module in which, when capacitor elements are electrically connected to each other by a plurality of connection terminals, electrical connection between the connection terminals can be easily achieved. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a schematic perspective view showing an example of a capacitor module according to a first embodiment of the present invention. [Diagram 2]FIG. 2 is a schematic perspective view showing an example of the capacitor module shown in FIG. 1 in an exploded state. [Diagram 3] FIG. 3 is a schematic cross-sectional view showing an example of a cross section of the capacitor module shown in FIG. 1 taken along line segment A1-A2. [Figure 4] FIG. 4 is a schematic perspective view showing an example of the capacitor element shown in FIGS. 1, 2, and 3. As shown in FIG. [Diagram 5] FIG. 5 is a schematic cross-sectional view showing an example of a cross section of the capacitor element shown in FIG. 4 taken along line segment B1-B2. [Figure 6] FIG. 6 is a schematic cross-sectional view showing another example of the capacitor module according to the first embodiment of the present invention. [Figure 7] FIG. 7 is a schematic cross-sectional view showing an example of a capacitor module according to the second embodiment of the present invention. [Figure 8] FIG. 8 is a schematic cross-sectional view showing an example of a capacitor module according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] The capacitor module of the present invention will be described below. Note that the present invention is not limited to the following configuration, and may be modified as appropriate without departing from the gist of the present invention. In addition, a combination of multiple individual preferred configurations described below also constitutes the present invention.

[0016] The following embodiments are merely examples, and it goes without saying that partial replacement or combination of the configurations shown in different embodiments is possible. In the second and subsequent embodiments, the description of the matters common to the first embodiment will be omitted, and the differences will be mainly described. In particular, the same effects and advantages due to the same configuration will not be mentioned one by one for each embodiment.

[0017] In the following description, unless there is a need to distinguish between the various embodiments, they will simply be referred to as the "capacitor module of the present invention."

[0018] In the following, a film capacitor will be described as an example of a capacitor element of the capacitor module of the present invention, however, the capacitor module of the present invention can also be applied to capacitor elements other than film capacitors.

[0019] The drawings shown below are schematic diagrams, and the dimensions, aspect ratio, and scale may differ from those of the actual product.

[0020] In this specification, unless otherwise specified, terms indicating the relationship between elements (e.g., "parallel", "perpendicular", etc.) and terms indicating the shape of elements not only mean the literal strict form, but also mean a range that is substantially equivalent, for example, a range that includes a difference of about a few percent.

[0021] The capacitor module of the present invention comprises an element body, a plurality of capacitor elements, each of which has a first external electrode provided on one end face of the element body and a second external electrode provided on the other end face facing the one end face of the element body in a first direction, and a plurality of connection terminals electrically connected to the plurality of capacitor elements, the plurality of capacitor elements including a first capacitor element and a second capacitor element adjacent in the first direction such that the first external electrodes having the same polarity face each other and are spaced apart from each other, and the plurality of connection terminals include a first main connection terminal electrically connected to the first external electrodes of the first capacitor element and the second capacitor element at a position spaced from the first capacitor element and the second capacitor element, and a second connection terminal electrically connected to the first main connection terminal at one end side. the first sub-connection terminal has one end side electrically connected to the first external electrode of the first capacitor element, and the other end side of the second sub-connection terminal has one end side electrically connected to the first main connection terminal and the other end side electrically connected to the first external electrode of the second capacitor element, wherein the first main connection terminal has a first through hole, a dimension of the first through hole in the first direction is smaller than a maximum distance in the first direction between a surface of the first sub-connection terminal opposite to the second sub-connection terminal and a surface of the second sub-connection terminal opposite to the first sub-connection terminal, and the first sub-connection terminal and the second sub-connection terminal pass through the first through hole with the one ends in contact with each other and the other ends separated from each other.

[0022] [Embodiment 1] In the capacitor module of embodiment 1 of the present invention, when the first sub-connection terminal and the second sub-connection terminal are viewed as an integrated unit, the distance in the first direction between the first sub-connection terminal and the second sub-connection terminal increases from one end to the other end.

[0023] Fig. 1 is a schematic perspective view showing an example of a capacitor module according to a first embodiment of the present invention. Fig. 2 is a schematic perspective view showing an example of an exploded state of the capacitor module shown in Fig. 1. Fig. 3 is a schematic cross-sectional view showing an example of a cross-section along line segment A1-A2 of the capacitor module shown in Fig. 1.

[0024] The capacitor module 1 shown in FIGS. 1, 2, and 3 has a plurality of capacitor elements 10 and a plurality of connection terminals 20.

[0025] In FIG. 1 etc., the first direction D1, the second direction D2, and the third direction D3 are perpendicular to each other.

[0026] Fig. 4 is a schematic perspective view showing an example of the capacitor element shown in Fig. 1, Fig. 2, and Fig. 3. Fig. 5 is a schematic cross-sectional view showing an example of a cross-section along line segment B1-B2 of the capacitor element shown in Fig. 4.

[0027] A capacitor element 10 shown in FIGS. 4 and 5 has an element body 11, a first external electrode 12a, and a second external electrode 12b.

[0028] Body 11 is a wound body in which first metallized film 13a and second metallized film 13b are wound in a stacked state in second direction D2. In other words, capacitor element 10 is a wound-type film capacitor in which metallized films are stacked and wound.

[0029] Capacitor element 10 may be a laminated film capacitor (eg, rectangular parallelepiped) in which metallized films are laminated.

[0030] In terms of reducing the height of capacitor element 10, it is preferable that element body 11 has a flat cross-sectional shape when viewed in a cross section perpendicular to the winding axis direction (first direction D1 in FIGS. 4 and 5) of element body 11. Specifically, it is preferable that the cross-sectional shape of element body 11 is pressed into a flat shape such as an ellipse or oval, and that the thickness of the cross-sectional shape of element body 11 is smaller than when it is a perfect circle.

[0031] Whether or not the element has been pressed to have a flat cross-sectional shape can be confirmed, for example, by checking whether or not there are press marks on the element.

[0032] Capacitor element 10 may have a cylindrical winding axis that is disposed on the central axis of first metallized film 13a and second metallized film 13b in a wound state and serves as the winding axis when first metallized film 13a and second metallized film 13b are wound.

[0033] First metallized film 13a includes a first dielectric film 14a and a first metal layer 15a.

[0034] The first dielectric film 14a has a first main surface 14aa and a second main surface 14ab facing each other in the second direction D2.

[0035] The first metal layer 15a is provided on the first main surface 14aa of the first dielectric film 14a. Specifically, the first metal layer 15a is provided on the first main surface 14aa of the first dielectric film 14a so as to reach one side edge of the first dielectric film 14a in the first direction D1 but not to reach the other side edge of the first dielectric film 14a.

[0036] Second metallized film 13b includes second dielectric film 14b and second metal layer 15b.

[0037] The second dielectric film 14b has a first main surface 14ba and a second main surface 14bb facing each other in the second direction D2.

[0038] The second metal layer 15b is provided on the first main surface 14ba of the second dielectric film 14b. Specifically, the second metal layer 15b is provided on the first main surface 14ba of the second dielectric film 14b so as not to reach one side edge of the second dielectric film 14b in the first direction D1 but to reach the other side edge of the second dielectric film 14b.

[0039] In element body 11, adjacent first metallized films 13a and second metallized films 13b are shifted in first direction D1 so that an end of first metal layer 15a that reaches a side edge of first dielectric film 14a is exposed at one end face of element body 11, and an end of second metal layer 15b that reaches a side edge of second dielectric film 14b is exposed at the other end face opposite to one end face of element body 11 in first direction D1. That is, in adjacent first metallized films 13a and second metallized films 13b, first metallized film 13a protrudes toward first external electrode 12a relative to second metallized film 13b. In addition, in adjacent first metallized films 13a and second metallized films 13b, second metallized film 13b protrudes toward second external electrode 12b relative to first metallized film 13a. In this state, the first metal layer 15a is connected to the first external electrode 12a, but is not connected to the second external electrode 12b. Also, the second metal layer 15b is connected to the second external electrode 12b, but is not connected to the first external electrode 12a.

[0040] In element body 11, adjacent first metallized films 13a and second metallized films 13b are shifted in first direction D1 as described above, so that, among adjacent first dielectric films 14a and second dielectric films 14b, first dielectric film 14a having first metal layer 15a provided on first main surface 14aa protrudes toward first external electrode 12a relative to second dielectric film 14b having no first metal layer 15a provided on its main surface. Also, among adjacent first dielectric film 14a and second dielectric film 14b, second dielectric film 14b having second metal layer 15b provided on first main surface 14ba protrudes toward second external electrode 12b relative to first dielectric film 14a having no second metal layer 15b provided on its main surface.

[0041] Since element body 11 is formed by winding first metallized film 13a and second metallized film 13b in a stacked state in second direction D2, it can be said that element body 11 includes first dielectric film 14a, first metal layer 15a, second dielectric film 14b, and second metal layer 15b in that order in second direction D2. It can also be said that element body 11 is a wound body formed by winding first dielectric film 14a, first metal layer 15a, second dielectric film 14b, and second metal layer 15b in that order in second direction D2.

[0042] In element body 11, first main surface 14aa of first dielectric film 14a and second main surface 14bb of second dielectric film 14b face each other in second direction D2, and second main surface 14ab of first dielectric film 14a and first main surface 14ba of second dielectric film 14b face each other in second direction D2. Thus, in element body 11, first metallized film 13a and second metallized film 13b are wound in a state in which they are stacked in second direction D2. In other words, in element body 11, first metallized film 13a and second metallized film 13b are wound in a state in which they are stacked in second direction D2 such that second metallized film 13b is on the inside of first metallized film 13a, specifically, first metal layer 15a is on the inside of first dielectric film 14a, and second metal layer 15b is on the inside of second dielectric film 14b. That is, in element body 11, first metal layer 15a and second metal layer 15b face each other with first dielectric film 14a or second dielectric film 14b sandwiched therebetween.

[0043] The first metal layer 15a may be provided with a fuse portion. The fuse portion provided in the first metal layer 15a is, for example, a portion that connects a divided electrode portion in which a portion of the first metal layer 15a facing the second metal layer 15b is divided into a plurality of portions, and an electrode portion that is a portion that does not face the second metal layer 15b. Examples of the electrode pattern of the first metal layer 15a provided with the fuse portion include the electrode patterns disclosed in JP-A-2004-363431 and JP-A-5-251266.

[0044] Similar to the first metal layer 15a, the second metal layer 15b may also be provided with a fuse portion.

[0045] The first dielectric film 14a may contain a curable resin as a main component.

[0046] In this specification, the term "major component" means the component having the highest weight percentage, and preferably means the component having a weight percentage greater than 50% by weight.

[0047] The curable resin may be a thermosetting resin or a photocurable resin.

[0048] In this specification, the term "thermosetting resin" refers to a resin that can be cured by heat, but does not limit the curing method. Therefore, the term "thermosetting resin" includes resins that can be cured by methods other than heat (for example, light, electron beam, etc.) as long as they are resins that can be cured by heat. In addition, depending on the material, a reaction may start due to the reactivity of the material itself, and resins that proceed to cure without necessarily applying heat from the outside are also considered to be thermosetting resins. The same applies to photocurable resins, and as long as they are resins that can be cured by light, they also include resins that can be cured by methods other than light (for example, heat, etc.).

[0049] The curable resin is preferably a cured product of a first organic material having a hydroxyl group (OH group) and a second organic material having an isocyanate group (NCO group). In this case, the curable resin is a cured product having a urethane bond obtained by reacting the hydroxyl group of the first organic material with the isocyanate group of the second organic material.

[0050] The presence of urethane bonds in the dielectric film can be confirmed by analysis with a Fourier transform infrared spectrophotometer (FT-IR).

[0051] When the curable resin is obtained by the above-mentioned reaction, an uncured portion of the starting material may remain in the first dielectric film 14a. For example, the first dielectric film 14a may contain at least one of a hydroxyl group and an isocyanate group. In this case, the first dielectric film 14a may contain either a hydroxyl group or an isocyanate group, or may contain both a hydroxyl group and an isocyanate group.

[0052] The presence of hydroxyl groups and / or isocyanate groups in the dielectric film can be confirmed by FT-IR analysis.

[0053] Examples of the first organic material include a phenoxy resin, a polyvinyl acetoacetal resin, and a polyvinyl butyral resin.

[0054] As the first organic material, a plurality of types of organic materials may be used in combination.

[0055] Examples of the second organic material include aromatic polyisocyanates such as diphenylmethane diisocyanate (MDI) and tolylene diisocyanate (TDI), and aliphatic polyisocyanates such as hexamethylene diisocyanate (HDI), etc. As the second organic material, at least one modified product of these polyisocyanates may be used, or a mixture of at least one of these polyisocyanates and its modified product may be used.

[0056] As the second organic material, a plurality of types of organic materials may be used in combination.

[0057] The first dielectric film 14a may contain a thermoplastic resin as a main component.

[0058] Examples of the thermoplastic resin include polypropylene resin, polyethersulfone resin, polyetherimide resin, and polyarylate resin.

[0059] The first dielectric film 14a may contain additives to impart various functions.

[0060] The additives include, for example, a leveling agent for imparting smoothness.

[0061] The additive preferably has a functional group that reacts with a hydroxyl group and / or an isocyanate group and forms a part of the crosslinked structure of the cured product. Examples of such additives include resins having at least one functional group selected from the group consisting of a hydroxyl group, an epoxy group, a silanol group, and a carboxyl group.

[0062] Like the first dielectric film 14a, the second dielectric film 14b may contain a thermosetting resin as a main component, a photocurable resin as a main component, or a thermoplastic resin as a main component, and like the first dielectric film 14a, the second dielectric film 14b may also contain an additive.

[0063] The first dielectric film 14a and the second dielectric film 14b may have different compositions, but preferably have the same composition.

[0064] The thickness of the first dielectric film 14a and the second dielectric film 14b is preferably 1 μm or more and 10 μm or less, and more preferably 3 μm or more and 5 μm or less.

[0065] The first dielectric film 14a and the second dielectric film 14b may have different thicknesses, but preferably have the same thickness.

[0066] The thickness of the dielectric film is measured using an optical thickness gauge.

[0067] The first dielectric film 14a and the second dielectric film 14b are each preferably produced by forming a resin solution containing the above-mentioned resin material into a film and then curing it by heat treatment.

[0068] Examples of materials constituting the first metal layer 15a and the second metal layer 15b include metals such as aluminum, zinc, titanium, magnesium, tin, and nickel.

[0069] The compositions of the first metal layer 15a and the second metal layer 15b may be different from each other, but are preferably the same.

[0070] The thickness of the first metal layer 15a and the second metal layer 15b is preferably 5 nm or more and 40 nm or less.

[0071] The thickness of the first metal layer 15a and the second metal layer 15b may be different from each other, but it is preferable that they are the same.

[0072] The thickness of the metal layer is measured by observing a cross section of the metallized film along the second direction using a transmission electron microscope (TEM).

[0073] The first and second metal layers 15a and 15b are preferably formed by vapor deposition of a metal, such as those described above, onto the major surfaces of the first and second dielectric films 14a and 14b, respectively.

[0074] Although the embodiment in which element body 11 includes two metallized films has been described above, element body 11 may include one metallized film. For example, element body 11 may include a metallized film having first dielectric film 14a in which first metal layer 15a is provided on first main surface 14aa and second metal layer 15b is provided on second main surface 14ab, and second dielectric film 14b in which no metal layer is provided. Alternatively, element body 11 may include a metallized film having second dielectric film 14b in which first metal layer 15a is provided on second main surface 14bb and second metal layer 15b is provided on first main surface 14ba, and first dielectric film 14a in which no metal layer is provided.

[0075] The first external electrode 12a is provided on one end surface of the element body 11. Specifically, the first external electrode 12a is connected to the first metal layer 15a by contacting an end of the first metal layer 15a exposed on one end surface of the element body 11. On the other hand, the first external electrode 12a is not connected to the second metal layer 15b.

[0076] The second external electrode 12b is provided on the other end face opposing in the first direction D1 to the one end face of the element body 11. Specifically, the second external electrode 12b is connected to the second metal layer 15b by contacting an end of the second metal layer 15b exposed on the other end face of the element body 11. On the other hand, the second external electrode 12b is not connected to the first metal layer 15a.

[0077] Examples of materials constituting the first external electrode 12a and the second external electrode 12b include metals such as zinc, aluminum, tin, and zinc-aluminum alloys.

[0078] The first external electrode 12a and the second external electrode 12b may have different compositions, but preferably have the same composition.

[0079] The first external electrode 12a and the second external electrode 12b are preferably formed by spraying a metal such as those described above onto one end face and the other end face of the element body 11, respectively.

[0080] As described above, each of the capacitor elements 10 has the element body 11, the first external electrode 12a, and the second external electrode 12b.

[0081] As shown in FIGS. 1 and 2, the plurality of capacitor elements 10 includes a first capacitor element 10a and a second capacitor element 10b.

[0082] The first capacitor element 10a and the second capacitor element 10b are adjacent to each other in the first direction D1 such that the first external electrodes 12a having the same polarity (positive or negative) face each other at a distance.

[0083] The number of the plurality of capacitor elements 10 is not particularly limited as long as it is two or more including the first capacitor element 10a and the second capacitor element 10b.

[0084] The following describes a manner in which the multiple connection terminals 20 are connected to the first capacitor element 10a and the second capacitor element 10b that are adjacent in the first direction D1 such that the first external electrodes 12a face each other and are spaced apart from each other.

[0085] The multiple connection terminals 20 are electrically connected to the multiple capacitor elements 10 .

[0086] The multiple connection terminals 20 are used as terminals for electrically connecting the multiple capacitor elements 10 to an object to which the capacitor module 1 is to be mounted, for example.

[0087] As shown in FIGS. 1 and 2, the multiple connection terminals 20 include a first main connection terminal 21a, a first sub-connection terminal 22a, and a second sub-connection terminal 22b.

[0088] The first main connection terminal 21a extends in a first direction D1.

[0089] The first main connection terminal 21a is electrically connected to the first external electrodes 12a of the first capacitor element 10a and the second capacitor element 10b at a position away from the first capacitor element 10a and the second capacitor element 10b (in Figure 1, a position away in the second direction D2).

[0090] The first main connection terminal 21a is preferably shaped like a plate, in which case the first main connection terminal 21a is also called a bus bar.

[0091] When viewed from the first direction D1, the first main connection terminal 21a may be L-shaped (or inverted L-shaped) in which a portion extending in the second direction D2 and a portion extending in the third direction D3 are connected at their tips, as shown in Figures 1 and 2, or it may have some other shape.

[0092] The first main connection terminal 21a is provided with a first through hole 31a. Specifically, the first through hole 31a penetrates the first main connection terminal 21a in the second direction D2.

[0093] The planar shape of the first through hole 31a when viewed from the second direction D2 is not particularly limited, and examples thereof include a rectangle such as a rectangle or a square, a circle, an ellipse, a combination of these, and the like.

[0094] The cross-sectional shape of the first through hole 31a when viewed in a cross section along the second direction D2 is not particularly limited, and may be a shape in which the dimension P1 (see Figure 3) of the first through hole 31a in the first direction D1 is constant toward the first capacitor element 10a and the second capacitor element 10b, or a shape in which the dimension P1 of the first through hole 31a in the first direction D1 is not constant.

[0095] If the cross-sectional shape of the first through hole 31a when viewed along the second direction D2 is a shape in which the dimension P1 of the first through hole 31a in the first direction D1 is not constant toward the first capacitor element 10a and the second capacitor element 10b, for example, the cross-sectional shape of the first through hole 31a when viewed along the second direction D2 may be a shape in which the dimension P1 of the first through hole 31a in the first direction D1 becomes smaller toward the first capacitor element 10a and the second capacitor element 10b, or a shape in which the dimension P1 of the first through hole 31a in the first direction D1 becomes larger.

[0096] As shown in Figure 3, the dimension P1 of the first through hole 31a in the first direction D1 is smaller than the maximum distance Q1 in the first direction D1 between the surface 22aa of the first sub-connecting terminal 22a opposite the second sub-connecting terminal 22b and the surface 22ba of the second sub-connecting terminal 22b opposite the first sub-connecting terminal 22a.

[0097] Furthermore, if the cross-sectional shape of the first through hole 31a when viewed along a cross section in the second direction D2 is a shape in which the dimension P1 of the first through hole 31a in the first direction D1 is not constant toward the first capacitor element 10a and the second capacitor element 10b, it is preferable that the maximum value of the dimension P1 of the first through hole 31a in the first direction D1 is smaller than the maximum distance Q1 in the first direction D1 between the surface 22aa of the first sub-connecting terminal 22a opposite the second sub-connecting terminal 22b and the surface 22ba of the second sub-connecting terminal 22b opposite the first sub-connecting terminal 22a.

[0098] The dimension of the first through hole 31a in the third direction D3 is not particularly limited as long as it is larger than the dimensions of the first sub-connection terminal 22a and the second sub-connection terminal 22b in the third direction D3.

[0099] 3, the first sub-connection terminal 22a is electrically connected at one end to the first main connection terminal 21a and at the other end to the first external electrode 12a of the first capacitor element 10a. In other words, the first main connection terminal 21a is electrically connected to the first external electrode 12a of the first capacitor element 10a via the first sub-connection terminal 22a. That is, the first main connection terminal 21a is provided at a position electrically farther from the first external electrode 12a of the first capacitor element 10a than the first sub-connection terminal 22a is.

[0100] It is preferable that one end of the first sub-connection terminal 22a contacts the first main connection terminal 21a.

[0101] The first sub-connection terminal 22a may be connected at one end to the first main connection terminal 21a via a joining member such as solder, or may be welded.

[0102] The other end of first sub-connection terminal 22a is preferably in contact with first outer electrode 12a of first capacitor element 10a.

[0103] The other end of first sub-connection terminal 22a may be connected to first outer electrode 12a of first capacitor element 10a via a joining member such as solder, or may be welded.

[0104] When connecting the first capacitor element 10a and the connection terminal 20, by making the connection terminal 20 a separate combination of the first main connection terminal 21a and the first sub-connection terminal 22a as described above, it becomes easier to connect the first capacitor element 10a and the connection terminal 20 compared to a case in which the first main connection terminal 21a and the first sub-connection terminal 22a are not a separate combination.

[0105] 3, the second sub-connection terminal 22b is electrically connected at one end to the first main connection terminal 21a and at the other end to the first external electrode 12a of the second capacitor element 10b. In other words, the first main connection terminal 21a is electrically connected to the first external electrode 12a of the second capacitor element 10b via the second sub-connection terminal 22b. That is, the first main connection terminal 21a is provided at a position electrically farther from the first external electrode 12a of the second capacitor element 10b than the second sub-connection terminal 22b is.

[0106] It is preferable that one end of the second sub-connection terminal 22b contacts the first main connection terminal 21a.

[0107] The second sub-connection terminal 22b may be connected at one end to the first main connection terminal 21a via a joining member such as solder, or may be welded.

[0108] The second sub-connection terminal 22b preferably contacts, at the other end side, the first outer electrode 12a of the second capacitor element 10b.

[0109] The second sub-connection terminal 22b may be connected, at the other end side, to the first outer electrode 12a of the second capacitor element 10b via a joining member such as solder, or may be welded.

[0110] When connecting the second capacitor element 10b and the connection terminal 20, by making the connection terminal 20 a separate combination of the first main connection terminal 21a and the second sub-connection terminal 22b as described above, it becomes easier to connect the second capacitor element 10b and the connection terminal 20 compared to a case in which the first main connection terminal 21a and the second sub-connection terminal 22b are not a separate combination.

[0111] The first sub-connection terminal 22a and the second sub-connection terminal 22b are preferably shaped like a plate, in which case the first sub-connection terminal 22a and the second sub-connection terminal 22b are also called bus bars.

[0112] The first sub-connection terminal 22a and the second sub-connection terminal 22b may have a rod-like (linear) shape. In this case, the first sub-connection terminal 22a and the second sub-connection terminal 22b are also called lead terminals.

[0113] The thickness of the first sub-connection terminal 22a and the second sub-connection terminal 22b may be the same as each other or may be different from each other.

[0114] The dimensions of the first sub-connection terminal 22a and the second sub-connection terminal 22b in the extension direction may be the same as each other or may be different from each other.

[0115] Examples of materials for the first main connection terminal 21a, the first sub-connection terminal 22a, and the second sub-connection terminal 22b include metals such as copper, oxygen-free copper, aluminum, and alloys containing at least one of these. Among them, the materials for the first main connection terminal 21a, the first sub-connection terminal 22a, and the second sub-connection terminal 22b are preferably copper or oxygen-free copper. When the materials for the first main connection terminal 21a, the first sub-connection terminal 22a, and the second sub-connection terminal 22b are copper-based materials, examples of materials that can be used include oxygen-free copper (copper: 99.96% by weight or more), tough pitch copper (copper: 99.90% by weight or more), and phosphorus-deoxidized copper (copper: 99.90% by weight or more, phosphorus: 0.015% by weight or more, 0.040% by weight or less).

[0116] The constituent materials of the first main connection terminal 21a, the first sub-connection terminal 22a, and the second sub-connection terminal 22b may be the same as one another, may be different from one another, or may be partially different from one another.

[0117] The thicknesses of the first main connection terminal 21a, the first sub-connection terminal 22a, and the second sub-connection terminal 22b may be the same as each other, may be different from each other, or may be partially different.

[0118] 3, the first sub-connection terminal 22a and the second sub-connection terminal 22b pass through the first through hole 31a with one ends in contact with each other and the other ends separated from each other. With the first sub-connection terminal 22a and the second sub-connection terminal 22b passing through the first through hole 31a, one end of each of them is located on the opposite side of the first capacitor element 10a and the second capacitor element 10b with respect to the first through hole 31a, and the other end of each of them is located on the first capacitor element 10a and the second capacitor element 10b side with respect to the first through hole 31a.

[0119] In the capacitor module 1, the first sub-connection terminal 22a and the second sub-connection terminal 22b are in a state in which one ends are in contact with each other and the other ends are separated from each other, so that the first sub-connection terminal 22a and the second sub-connection terminal 22b can easily pass through the first through hole 31a on the one end side.

[0120] One end of the first sub-connection terminal 22a and one end of the second sub-connection terminal 22b may be joined to each other by welding or the like, or may simply be in contact with each other without being joined.

[0121] As described above, in the capacitor module 1, the dimension P1 of the first through hole 31a in the first direction D1 is smaller than the maximum distance Q1 in the first direction D1 between the surface 22aa of the first sub-connecting terminal 22a opposite to the second sub-connecting terminal 22b and the surface 22ba of the second sub-connecting terminal 22b opposite to the first sub-connecting terminal 22a. Therefore, in the capacitor module 1, when the first sub-connecting terminal 22a and the second sub-connecting terminal 22b pass through the first through hole 31a, the first sub-connecting terminal 22a and the second sub-connecting terminal 22b are electrically connected to the first main connecting terminal 21a, specifically, to the periphery of the first through hole 31a, at a position between one end and the other end, as shown in FIG. 3. Therefore, in the capacitor module 1, the first main connecting terminal 21a can be electrically connected to the first sub-connecting terminal 22a and the second sub-connecting terminal 22b at a position away from the first capacitor element 10a and the second capacitor element 10b, as shown in FIG. 3.

[0122] In the capacitor module 1, the first main connection terminal 21a is electrically connected to the first sub-connection terminal 22a and the second sub-connection terminal 22b, so that the first capacitor element 10a and the second capacitor element 10b are electrically connected via the first main connection terminal 21a, the first sub-connection terminal 22a, and the second sub-connection terminal 22b.

[0123] In the capacitor module 1, when the first main connection terminal 21a is electrically connected to the first sub-connection terminal 22a and the second sub-connection terminal 22b, as long as one end side of each of the first sub-connection terminal 22a and the second sub-connection terminal 22b passes through the first through hole 31a, it is not necessary to strictly match the size of the first through hole 31a (e.g., the dimension in the first direction D1) to the size of the first sub-connection terminal 22a and the second sub-connection terminal 22b (e.g., the dimension in the first direction D1). Therefore, in the capacitor module 1, when processing is performed to provide the first through hole 31a in the first main connection terminal 21a, the constraints on the size of the first through hole 31a are alleviated compared to conventional capacitor modules (e.g., the capacitor module described in Patent Document 1 and the capacitor described in Patent Document 2).

[0124] As described above, in the capacitor module 1, when the first capacitor element 10a and the second capacitor element 10b are electrically connected by the first main connection terminal 21a, the first sub-connection terminal 22a, and the second sub-connection terminal 22b, the electrical connection of the first main connection terminal 21a, the first sub-connection terminal 22a, and the second sub-connection terminal 22b can be easily achieved.

[0125] Here, consider a conventional capacitor module in which two through holes are provided in the first main connection terminal, and the first sub-connection terminal and the second sub-connection terminal pass separately through the two through holes in a parallel state with a gap between them.

[0126] In conventional capacitor modules, when the distance between the first capacitor element and the second capacitor element becomes smaller, the distance between the first sub-connection terminal and the second sub-connection terminal becomes smaller, and therefore the distance between the through hole through which the first sub-connection terminal passes and the through hole through which the second sub-connection terminal passes becomes smaller, but it is difficult to process the first main connection terminal to provide a through hole with a small distance. Thus, in conventional capacitor modules, because it is difficult to process the first main connection terminal to provide a through hole with a small distance, there is a limit to how small the distance between the first capacitor element and the second capacitor element can be made.

[0127] Furthermore, in the conventional capacitor module, when processing is performed to provide through holes in the first main connection terminal, if the interval between the through holes is made too small, the through holes are connected to each other. In the conventional capacitor module, when the through holes provided in the first main connection terminal are connected to each other, the through holes are present in the gap between the first sub-connection terminal and the second sub-connection terminal, and a path is created through the through holes from the opposite side of the first capacitor element and the second capacitor element to the first capacitor element and the second capacitor element side with respect to the first main connection terminal. Therefore, in the conventional capacitor module, for example, when the first main connection terminal is soldered to the first sub-connection terminal and the second sub-connection terminal on the opposite side of the first capacitor element and the second capacitor element, the solder is likely to leak through the through holes to the first capacitor element and the second capacitor element side. Therefore, in the conventional capacitor module, various members are likely to be connected at places other than the desired places, for example, the main connection terminal and the first external electrode are likely to be connected via solder.

[0128] In contrast, in the capacitor module 1, it is sufficient that the first main connection terminal 21a is provided with one first through hole 31a through which the first sub-connection terminal 22a and the second sub-connection terminal 22b pass together, and there is no need to provide two through holes through which the first sub-connection terminal 22a and the second sub-connection terminal 22b pass separately. Therefore, in the capacitor module 1, the process of providing a through hole in the first main connection terminal 21a is simplified. Furthermore, in the capacitor module 1, even if it is desired to reduce the interval between the first capacitor element 10a and the second capacitor element 10b, there is no need to perform a difficult process of providing a through hole with a small interval in the first main connection terminal 21a. Therefore, in the capacitor module 1, it is possible to reduce the interval between the first capacitor element 10a and the second capacitor element 10b. In the capacitor module 1, even if the distance between the first capacitor element 10a and the second capacitor element 10b is small, the above-mentioned configuration makes it possible for the first main connection terminal 21a to be electrically connected to the first sub-connection terminal 22a and the second sub-connection terminal 22b.

[0129] Furthermore, in the capacitor module 1, the first sub-connection terminal 22a and the second sub-connection terminal 22b are electrically connected to the first main connection terminal 21a by passing through the first through hole 31a with one end of each terminal in contact with each other, so that it is possible to prevent a path from passing through the first through hole 31a from the side opposite the first capacitor element 10a and the second capacitor element 10b toward the first capacitor element 10a and the second capacitor element 10b side to the first main connection terminal 21a. Therefore, in the capacitor module 1, for example, even if the first main connection terminal 21a is soldered to the first sub-connection terminal 22a and the second sub-connection terminal 22b on the side opposite the first capacitor element 10a and the second capacitor element 10b, the solder is unlikely to leak through the first through hole 31a to the first capacitor element 10a and the second capacitor element 10b side. Therefore, in the capacitor module 1, it is less likely that various components will be connected at locations other than the desired locations, for example, that the first main connection terminal 21a and the first external electrode 12a will be connected via solder rather than via the first sub-connection terminal 22a and the second sub-connection terminal 22b.

[0130] Furthermore, in the capacitor module 1, it is sufficient to provide the first main connection terminal 21a with one first through hole 31a through which the first sub-connection terminal 22a and the second sub-connection terminal 22b pass together, and the size of the first through hole 31a (e.g., the dimension in the first direction D1) can be made small to the extent that one end side of each of the first sub-connection terminal 22a and the second sub-connection terminal 22b passes through. In the capacitor module 1, if the size of the first through hole 31a is small, for example, less preheating is required when soldering the first main connection terminal 21a to the first sub-connection terminal 22a and the second sub-connection terminal 22b, and therefore damage due to heat during soldering is less likely to extend to the multiple capacitor elements 10, in particular the first capacitor element 10a and the second capacitor element 10b.

[0131] Furthermore, in the capacitor module 1, the first capacitor element 10a and the second capacitor element 10b are adjacent to each other in the first direction D1 so that the first external electrodes 12a having the same polarity are spaced apart and facing each other. This also means that the current path from the first external electrodes 12a of the first capacitor element 10a and the second capacitor element 10b through the first sub-connection terminal 22a and the second sub-connection terminal 22b to the first main connection terminal 21a is short, making it difficult for the equivalent series inductance to become large.

[0132] The arrangement of the first sub-connection terminal 22a and the second sub-connection terminal 22b may be such that one ends are in contact with each other and the other ends are separated from each other. Therefore, the arrangement of the first sub-connection terminal 22a and the second sub-connection terminal 22b does not include an arrangement in which the entire terminals are in contact from one end to the other end, and an arrangement in which the entire terminals are separated from each other from one end to the other end.

[0133] In the example shown in Figure 3, when the first sub-connection terminal 22a and the second sub-connection terminal 22b are viewed as an integrated unit, the distance in the first direction D1 between the first sub-connection terminal 22a and the second sub-connection terminal 22b increases from one end to the other end.

[0134] In the example shown in FIG. 3, the first sub-connection terminal 22a and the second sub-connection terminal 22b each extend linearly.

[0135] The first sub-connection terminal 22a and the second sub-connection terminal 22b may be arranged in a manner other than the example shown in FIG.

[0136] FIG. 6 is a schematic cross-sectional view showing another example of the capacitor module according to the first embodiment of the present invention.

[0137] FIG. 6 shows a cross section taken at a position corresponding to FIG.

[0138] In the capacitor module 1' shown in Figure 6, as in the capacitor module 1 shown in Figure 3, when the first sub-connection terminal 22a and the second sub-connection terminal 22b are viewed as an integrated unit, the distance in the first direction D1 between the first sub-connection terminal 22a and the second sub-connection terminal 22b increases from one end to the other end.

[0139] In the example shown in FIG. 6, the first sub-connection terminal 22a and the second sub-connection terminal 22b each extend in a curved shape.

[0140] In the example shown in Figure 6, compared to the example shown in Figure 3, the first sub-connection terminal 22a and the second sub-connection terminal 22b are curved so as to approach each other in the first direction D1, but they may also be curved so as to move away from each other in the first direction D1.

[0141] 1 and 2, in the capacitor module 1, first capacitor elements 10a and second capacitor elements 10b may be provided alternately and repeatedly in the first direction D1 as the multiple capacitor elements 10. That is, in the capacitor module 1, a unit formed by providing the first capacitor element 10a and the second capacitor element 10b in the first direction D1 may be used as a constituent unit, and a plurality of such units may be arranged in the first direction D1.

[0142] As shown in Figures 1 and 2, when the first capacitor elements 10a and the second capacitor elements 10b are arranged alternately in a first direction D1, the first capacitor elements 10a and the second capacitor elements 10b are adjacent to each other in the first direction D1 so that the second external electrodes 12b having the same polarity (different polarity from the first external electrode 12a) face each other at a distance.

[0143] The following describes a connection mode of the multiple connection terminals 20 to the first capacitor element 10a and the second capacitor element 10b that are adjacent in the first direction D1 such that the second external electrodes 12b face each other and are spaced apart from each other.

[0144] As shown in Figures 1 and 2, the multiple connection terminals 20 may further include, in addition to the first main connection terminal 21a, the first sub-connection terminal 22a, and the second sub-connection terminal 22b, a second main connection terminal 21b, a third sub-connection terminal 22c, and a fourth sub-connection terminal 22d.

[0145] The second main connection terminal 21b extends in the first direction D1. In the example shown in Figures 1 and 2, the second main connection terminal 21b extends in the first direction D1 to be parallel to the first main connection terminal 21a, with a gap between the second main connection terminal 21b and the first main connection terminal 21a in the third direction D3.

[0146] The second main connection terminal 21b is electrically connected to the second outer electrodes 12b of the first capacitor element 10a and the second capacitor element 10b at a position away from the first capacitor element 10a and the second capacitor element 10b (in FIG. 1, a position away in the second direction D2).

[0147] When viewed from the first direction D1, the second main connection terminal 21b may be L-shaped (or inverted L-shaped) in which a portion extending in the second direction D2 and a portion extending in the third direction D3 are connected at their tips, as shown in Figures 1 and 2, or it may have some other shape.

[0148] When viewed from the first direction D1, the second main connection terminal 21b may have a shape that is line-symmetrical to the first main connection terminal 21a, as shown in Figures 1 and 2, or may have a shape that is not line-symmetrical to the first main connection terminal 21a.

[0149] In FIG. 2, the first main connection terminal 21a and the second main connection terminal 21b are shown separated in the third direction D3 compared to FIG. 1 so that the overall picture can be easily understood.

[0150] The second main connection terminal 21b is provided with a second through hole 31b. Specifically, the second through hole 31b penetrates the second main connection terminal 21b in the second direction D2.

[0151] The dimension of the second through hole 31b in the first direction D1 is smaller than the maximum distance in the first direction D1 between the surface of the third sub-connecting terminal 22c opposite the fourth sub-connecting terminal 22d and the surface of the fourth sub-connecting terminal 22d opposite the third sub-connecting terminal 22c.

[0152] Furthermore, if the cross-sectional shape of the second through hole 31b when viewed along a cross section in the second direction D2 is a shape in which the dimension of the second through hole 31b in the first direction D1 is not constant toward the first capacitor element 10a and the second capacitor element 10b, it is preferable that the maximum value of the dimension of the second through hole 31b in the first direction D1 is smaller than the maximum distance in the first direction D1 between the surface of the third sub-connecting terminal 22c opposite the fourth sub-connecting terminal 22d and the surface of the fourth sub-connecting terminal 22d opposite the third sub-connecting terminal 22c.

[0153] The third sub-connection terminal 22c is electrically connected at one end to the second main connection terminal 21b and at the other end to the second external electrode 12b of the first capacitor element 10a. In other words, the second main connection terminal 21b is electrically connected to the second external electrode 12b of the first capacitor element 10a via the third sub-connection terminal 22c. In other words, the second main connection terminal 21b is provided at a position electrically farther from the second external electrode 12b of the first capacitor element 10a than the third sub-connection terminal 22c is.

[0154] The fourth sub-connection terminal 22d is electrically connected at one end to the second main connection terminal 21b and at the other end to the second external electrode 12b of the second capacitor element 10b. In other words, the second main connection terminal 21b is electrically connected to the second external electrode 12b of the second capacitor element 10b via the fourth sub-connection terminal 22d. That is, the second main connection terminal 21b is provided at a position electrically farther from the second external electrode 12b of the second capacitor element 10b than the fourth sub-connection terminal 22d is.

[0155] The third sub-connection terminal 22c and the fourth sub-connection terminal 22d pass through the second through hole 31b with one ends in contact with each other and the other ends separated from each other. With the third sub-connection terminal 22c and the fourth sub-connection terminal 22d passing through the second through hole 31b, one end of each of them is located on the opposite side of the second through hole 31b to the first capacitor element 10a and the second capacitor element 10b, and the other end of each of them is located on the first capacitor element 10a and the second capacitor element 10b side with respect to the second through hole 31b.

[0156] In the capacitor module 1, the third sub-connection terminal 22c and the fourth sub-connection terminal 22d are in a state in which one ends are in contact with each other and the other ends are separated from each other, so that the third sub-connection terminal 22c and the fourth sub-connection terminal 22d can easily pass through the second through hole 31b on the one end side.

[0157] As described above, in the capacitor module 1, the dimension of the second through hole 31b in the first direction D1 is smaller than the maximum distance in the first direction D1 between the surface of the third sub-connecting terminal 22c opposite to the fourth sub-connecting terminal 22d and the surface of the fourth sub-connecting terminal 22d opposite to the third sub-connecting terminal 22c. Therefore, in the capacitor module 1, when the third sub-connecting terminal 22c and the fourth sub-connecting terminal 22d pass through the second through hole 31b, the third sub-connecting terminal 22c and the fourth sub-connecting terminal 22d are electrically connected to the second main connecting terminal 21b, specifically, to the periphery of the second through hole 31b, at a position between one end and the other end. Therefore, in the capacitor module 1, it is possible to electrically connect the second main connecting terminal 21b to the third sub-connecting terminal 22c and the fourth sub-connecting terminal 22d at a position away from the first capacitor element 10a and the second capacitor element 10b.

[0158] In the capacitor module 1, the second main connection terminal 21b is electrically connected to the third sub-connection terminal 22c and the fourth sub-connection terminal 22d, so that the first capacitor element 10a and the second capacitor element 10b are electrically connected via the second main connection terminal 21b, the third sub-connection terminal 22c, and the fourth sub-connection terminal 22d.

[0159] In the capacitor module 1, the electrical connection between the first main connection terminal 21a, the first sub-connection terminal 22a, and the second sub-connection terminal 22b can be easily achieved, as can the electrical connection between the second main connection terminal 21b, the third sub-connection terminal 22c, and the fourth sub-connection terminal 22d.

[0160] In the capacitor module 1, even if the distance between the first capacitor element 10a and the second capacitor element 10b is small, it is possible for the second main connection terminal 21b to be electrically connected to the third sub-connection terminal 22c and the fourth sub-connection terminal 22d.

[0161] Furthermore, in the capacitor module 1, for example, even if the second main connection terminal 21b is soldered to the third sub-connection terminal 22c and the fourth sub-connection terminal 22d on the side opposite to the first capacitor element 10a and the second capacitor element 10b, the solder is unlikely to leak through the second through-hole 31b to the first capacitor element 10a and the second capacitor element 10b side. Therefore, in the capacitor module 1, it is unlikely that various members will be connected at locations other than desired, for example, that the second main connection terminal 21b and the second external electrode 12b will be connected via solder instead of via the third sub-connection terminal 22c and the fourth sub-connection terminal 22d.

[0162] Furthermore, in the capacitor module 1, the size of the second through hole 31b (e.g., the dimension in the first direction D1) can be made small to the extent that one end side of each of the third sub-connection terminal 22c and the fourth sub-connection terminal 22d can pass through. In the capacitor module 1, if the size of the second through hole 31b is small, for example, less preheating is required when soldering the second main connection terminal 21b to the third sub-connection terminal 22c and the fourth sub-connection terminal 22d, and therefore damage caused by heat during soldering is less likely to extend to the multiple capacitor elements 10, in particular the first capacitor element 10a and the second capacitor element 10b.

[0163] Furthermore, in the capacitor module 1, the first capacitor element 10a and the second capacitor element 10b are adjacent to each other in the first direction D1 so that the second external electrodes 12b having the same polarity are spaced apart and facing each other. This also means that the current path from the second external electrodes 12b of the first capacitor element 10a and the second capacitor element 10b through the third sub-connection terminal 22c and the fourth sub-connection terminal 22d to the second main connection terminal 21b is short, making it difficult for the equivalent series inductance to become large.

[0164] Other features of the second main connection terminal 21b are similar to those of the first main connection terminal 21a.

[0165] Other features of the second through hole 31b are similar to those of the first through hole 31a.

[0166] Other features of the third sub-connection terminal 22c and the fourth sub-connection terminal 22d are similar to those of the first sub-connection terminal 22a and the second sub-connection terminal 22b.

[0167] The arrangement of the third sub-connection terminal 22c and the fourth sub-connection terminal 22d may be the same as that shown in FIG.

[0168] The capacitor module 1 may further include an exterior case in which a plurality of capacitor elements 10 are housed.

[0169] It is preferable that the plurality of capacitor elements 10 are housed inside the outer case so as to be spaced apart from the inner surface of the outer case.

[0170] The exterior case is, for example, a bottomed cylindrical shape with an opening. In this case, the exterior case may be a bottomed cylindrical shape with an opening at one end in the second direction D2. Specifically, the exterior case may have a bottom facing the opening in the second direction D2, and a sidewall extending from the bottom toward the opening in the second direction D2.

[0171] Examples of the exterior case include a resin case and a metal case.

[0172] When the exterior case is a resin case, examples of the resin constituting the resin case include liquid crystal polymer (LCP), polyphenylene sulfide resin, polybutylene terephthalate resin, etc. Among these, it is preferable that the resin case contains a liquid crystal polymer.

[0173] As the liquid crystal polymer contained in the resin case, for example, a liquid crystal polymer having p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid groups in the skeleton is used. In addition to p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid groups, liquid crystal polymers formed by polycondensation using various components such as phenol, phthalic acid, and ethylene terephthalate can be used. When classifying liquid crystal polymers, there are also classification methods such as type I, type II, and type III, but the material means the same material as the liquid crystal polymer formed from the above-mentioned components.

[0174] The resin case preferably further contains an inorganic filler in addition to the liquid crystal polymer.

[0175] The inorganic filler contained in the resin case may be a material having a higher strength than the liquid crystal polymer. The inorganic filler is preferably a material having a higher melting point than the liquid crystal polymer, and more preferably a material having a melting point of 680° C. or higher.

[0176] The form of the inorganic filler is not particularly limited, and examples thereof include a form having a longitudinal direction such as a fiber form or a plate form. As an inorganic filler having such a form, a plurality of types of inorganic materials may be used in combination. It is preferable that the resin case contains at least one of a fiber-shaped inorganic material and a plate-shaped inorganic material as an inorganic filler.

[0177] In this specification, the filler being fibrous means that the relationship between the longitudinal dimension in the longitudinal direction and the cross-sectional diameter in a cross section perpendicular to the longitudinal direction is longitudinal dimension / cross-sectional diameter ≧5 (i.e., the aspect ratio is 5:1 or more). Here, the cross-sectional diameter is the longest distance between two points on the circumference of the cross section. When the cross-sectional diameter varies in the longitudinal direction, the measurement is performed at the point where the cross-sectional diameter is the largest.

[0178] In this specification, the filler being plate-like means that the relationship between the cross-sectional diameter of the face having the largest projected area and the maximum height in the direction perpendicular to this cross section is cross-sectional diameter / maximum height ≧3.

[0179] The size of the inorganic filler is preferably 5 μm or more in diameter and 50 μm or more in length.

[0180] It is preferable that the inorganic filler is dispersed throughout the outer casing without agglomerating.

[0181] Examples of the inorganic filler include inorganic materials such as fibrous glass filler, plate-like talc or mica, etc. Among these, it is preferable that the inorganic filler contains fibrous glass filler as a main component.

[0182] Even when the resin case contains another resin (eg, polyphenylene sulfide resin) instead of the liquid crystal polymer, it is preferable that the resin case further contains an inorganic filler as described above.

[0183] The resin case is manufactured by a method such as injection molding.

[0184] When the exterior case is a metal case, examples of the metal constituting the metal case include simple metals such as aluminum, magnesium, iron, stainless steel, and copper, and alloys containing at least one of these simple metals. Among these, it is preferable that the metal case contains aluminum or an aluminum alloy.

[0185] The metal case is manufactured by a method such as impact molding.

[0186] In the capacitor module 1, one possible method for increasing the overall capacitance of the multiple capacitor elements 10 is to arrange a large number of the multiple capacitor elements 10. For example, when the multiple capacitor elements 10 are housed inside an exterior case, in order to arrange a large number of the multiple capacitor elements 10 within the interior space of the exterior case, it is possible to reduce the distance between adjacent capacitor elements 10. In contrast, in the capacitor module 1, as described above, it is possible to reduce the distance between adjacent capacitor elements 10, so that it is possible to increase the overall capacitance of the multiple capacitor elements 10 even when the multiple capacitor elements 10 are housed inside an exterior case.

[0187] The capacitor module 1 may further include a filling resin that fills the interior of the exterior case so as to embed the multiple capacitor elements 10. When the interior of the exterior case is filled with the filling resin in this manner, the multiple capacitor elements 10 are held inside the exterior case.

[0188] When the multiple capacitor elements 10 are stored inside the exterior case so as to be separated from the inner surface of the exterior case, the filling resin is preferably filled between the multiple capacitor elements 10 and the exterior case, more specifically, between the outer surface of the multiple capacitor elements 10 and the inner surface of the exterior case. Furthermore, the filling resin is preferably filled inside the exterior case, not only between the multiple capacitor elements 10 and the exterior case, but also in the region from the opening of the exterior case to the multiple capacitor elements 10.

[0189] As the filling resin, it is preferable to appropriately select a resin with low moisture permeability from the viewpoint of suppressing the infiltration of moisture into the capacitor element 10, and examples thereof include epoxy resin, silicone resin, urethane resin, etc. Examples of the curing agent for the epoxy resin include an amine curing agent, an imidazole curing agent, etc.

[0190] The filling resin may be the above-mentioned resin alone, or may be a resin to which a reinforcing agent has been added, such as silica or alumina, for the purpose of improving strength.

[0191] From the viewpoint of preventing moisture from penetrating into capacitor element 10, it is preferable that the thickness of the filling resin at the opening of the exterior case is large. The thickness of the filling resin at the opening of the exterior case is preferably sufficiently large within the range allowed by the volume (physical size) of the entire capacitor module 1, and specifically, is preferably 2 mm or more, and more preferably 4 mm or more. In particular, it is preferable that the thickness of the filling resin for the multiple capacitor elements 10 is made larger on the opening side of the exterior case than on the bottom side by arranging the multiple capacitor elements 10 closer to the bottom side than the opening side of the exterior case inside the exterior case.

[0192] The thickness of the filled resin is measured, for example, by using a soft X-ray device if it is in a non-destructive state, and by using a length measuring device such as a caliper if it is in a destructive state.

[0193] The relationship between the height of the outer case and the height of the filled resin in the second direction D2 is such that the thickness of the filled resin at the opening of the outer case is as large as possible, and it may be up to a position on the inside of the outer case, or it may be just about to the top, or it may overflow slightly due to surface tension.

[0194] At least a portion of each of the first main connection terminal 21a and the second main connection terminal 21b may protrude from the filled resin.

[0195] At least a portion of each of the first sub-connection terminal 22a, the second sub-connection terminal 22b, the third sub-connection terminal 22c, and the fourth sub-connection terminal 22d may be embedded in the filling resin.

[0196] [Embodiment 2] In the capacitor module of embodiment 2 of the present invention, when the first sub-connecting terminal and the second sub-connecting terminal are viewed as an integrated unit, there are, from one end toward the other end, a first region where the surface of the first sub-connecting terminal facing the second sub-connecting terminal and the surface of the second sub-connecting terminal facing the first sub-connecting terminal are in contact, and a second region in which the distance in the first direction between the first sub-connecting terminal and the second sub-connecting terminal is constant.

[0197] In the capacitor module according to the second embodiment of the present invention, when the first sub-connection terminal and the second sub-connection terminal are viewed as an integrated unit, the first region and the second region are continuously connected to each other.

[0198] Except for the above points, the capacitor module of the second embodiment of the present invention is similar to the capacitor module of the first embodiment of the present invention.

[0199] FIG. 7 is a schematic cross-sectional view showing an example of a capacitor module according to the second embodiment of the present invention.

[0200] FIG. 7 shows a cross section taken at a position corresponding to FIG.

[0201] In the capacitor module 2 shown in Figure 7, when the first sub-connection terminal 22a and the second sub-connection terminal 22b are viewed as an integrated unit, a first region R1 and a second region R2 exist in that order from one end to the other end.

[0202] In the first region R1, a surface 22ab of the first sub-connecting terminal 22a facing the second sub-connecting terminal 22b is in contact with a surface 22bb of the second sub-connecting terminal 22b facing the first sub-connecting terminal 22a.

[0203] In the second region R2, the distance between the first sub-connection terminal 22a and the second sub-connection terminal 22b in the first direction D1 is constant.

[0204] In the capacitor module 2, when the first sub-connection terminal 22a and the second sub-connection terminal 22b are viewed as an integrated unit, the first region R1 and the second region R2 are continuously connected to each other.

[0205] When the first sub-connection terminal 22a and the second sub-connection terminal 22b are viewed as an integrated unit, the ratio of the dimension of each of the first region R1 and the second region R2 in the second direction D2 to the dimension of the entire region in the second direction D2 is not particularly limited. Specifically, the dimensions of the first region R1 and the second region R2 in the second direction D2 may be the same as each other or different from each other. When the dimensions of the first region R1 and the second region R2 in the second direction D2 are different from each other, the dimension of the first region R1 in the second direction D2 may be larger than the dimension of the second region R2 in the second direction D2 or may be smaller than the dimension of the second region R2 in the second direction D2.

[0206] Figure 7 shows an example of the arrangement of the first sub-connection terminal 22a and the second sub-connection terminal 22b, but the arrangement of the third sub-connection terminal 22c and the fourth sub-connection terminal 22d (see Figure 1) may also be the same as that in Figure 7.

[0207] [Embodiment 3] In the capacitor module of embodiment 3 of the present invention, similarly to the capacitor module of embodiment 2 of the present invention, when the first sub-connection terminal and the second sub-connection terminal are viewed as an integrated unit, there are, in order from one end toward the other end, a first region where the surface of the first sub-connection terminal facing the second sub-connection terminal and the surface of the second sub-connection terminal facing the first sub-connection terminal are in contact, and a second region where the distance in the first direction between the first sub-connection terminal and the second sub-connection terminal is constant.

[0208] In the capacitor module of embodiment 3 of the present invention, unlike the capacitor module of embodiment 2 of the present invention, when the first sub-connection terminal and the second sub-connection terminal are viewed as an integrated unit, a third region in which the distance in the first direction between the first sub-connection terminal and the second sub-connection terminal increases from the first region side toward the second region side is further present so as to continuously connect between the first region and the second region.

[0209] FIG. 8 is a schematic cross-sectional view showing an example of a capacitor module according to a third embodiment of the present invention.

[0210] FIG. 8 shows a cross section taken at a position corresponding to FIG.

[0211] In the capacitor module 3 shown in Figure 8, when the first sub-connection terminal 22a and the second sub-connection terminal 22b are viewed as an integrated unit, in addition to the first region R1 and the second region R2, a third region R3 is further present so as to continuously connect between the first region R1 and the second region R2.

[0212] In the third region R3, the distance in the first direction D1 between the first sub-connection terminal 22a and the second sub-connection terminal 22b increases from the first region R1 side toward the second region R2 side.

[0213] In the example shown in Fig. 8, the first sub-connection terminal 22a and the second sub-connection terminal 22b each extend linearly in the third region R3, but may extend curvedly. When the first sub-connection terminal 22a and the second sub-connection terminal 22b each extend curvedly in the third region R3, the first sub-connection terminal 22a and the second sub-connection terminal 22b may be curved so as to approach each other in the first direction D1, or may be curved so as to move away from each other in the first direction D1, compared to the example shown in Fig. 8.

[0214] When the first sub-connection terminal 22a and the second sub-connection terminal 22b are viewed as an integrated unit, the ratio of the dimensions of the first region R1, the second region R2, and the third region R3 in the second direction D2 to the dimension of the entire region in the second direction D2 is not particularly limited. Specifically, the dimensions of the first region R1, the second region R2, and the third region R3 in the second direction D2 may be the same as each other, may be different from each other, or may be partially different. When the dimensions of the first region R1, the second region R2, and the third region R3 in the second direction D2 are different from each other or partially different from each other, the order of the magnitude relationship of the dimensions of each region in the second direction D2 is not particularly limited. For example, among the dimensions of the first region R1, the second region R2, and the third region R3 in the second direction D2, the dimension of the first region R1 in the second direction D2 may be maximum, the dimension of the second region R2 in the second direction D2 may be maximum, or the dimension of the third region R3 in the second direction D2 may be maximum. Also, among the dimensions of the first region R1, the second region R2, and the third region R3 in the second direction D2, the dimension of the first region R1 in the second direction D2 may be minimum, the dimension of the second region R2 in the second direction D2 may be minimum, or the dimension of the third region R3 in the second direction D2 may be minimum.

[0215] In the example shown in Figure 8, the first main connection terminal 21a is electrically connected to the first sub-connection terminal 22a and the second sub-connection terminal 22b in the first region R1, but may also be electrically connected in the third region R3.

[0216] Figure 8 shows an example of an arrangement of the first sub-connection terminal 22a and the second sub-connection terminal 22b, but the arrangement of the third sub-connection terminal 22c and the fourth sub-connection terminal 22d (see Figure 1) may also be the same as that in Figure 8.

[0217] The capacitor module of the present invention is useful for power conversion devices such as motor drive inverters mounted on electric vehicles.

[0218] The present specification discloses the following:

[0219] <1> a plurality of capacitor elements, each of which has an element body, a first external electrode provided on one end face of the element body, and a second external electrode provided on the other end face opposite to the one end face of the element body in a first direction; a plurality of connection terminals electrically connected to the plurality of capacitor elements; the plurality of capacitor elements include a first capacitor element and a second capacitor element adjacent to each other in the first direction such that the first external electrodes having the same polarity face each other at a distance; the multiple connection terminals include a first main connection terminal electrically connected to the first external electrodes of the first capacitor element and the second capacitor element at a position away from the first capacitor element and the second capacitor element, a first sub-connection terminal electrically connected to the first main connection terminal at one end side and electrically connected to the first external electrode of the first capacitor element at the other end side, and a second sub-connection terminal electrically connected to the first main connection terminal at one end side and electrically connected to the first external electrode of the second capacitor element at the other end side; The first main connection terminal is provided with a first through hole, a dimension of the first through hole in the first direction is smaller than a maximum distance in the first direction between a surface of the first sub-connecting terminal opposite to the second sub-connecting terminal and a surface of the second sub-connecting terminal opposite to the first sub-connecting terminal; A capacitor module characterized in that the first sub-connection terminal and the second sub-connection terminal pass through the first through hole with their one ends in contact with each other and their other ends spaced apart.

[0220] <2> When the first sub-connection terminal and the second sub-connection terminal are viewed as an integrated unit, a distance between the first sub-connection terminal and the second sub-connection terminal in the first direction increases from the one end portion to the other end portion. <1> The capacitor module according to claim 1 .

[0221] <3> The first sub-connection terminal and the second sub-connection terminal each extend linearly. <2> The capacitor module according to claim 1 .

[0222] <4> The first sub-connection terminal and the second sub-connection terminal each extend in a curved shape. <2> The capacitor module according to claim 1 .

[0223] <5> When the first sub-connection terminal and the second sub-connection terminal are viewed as an integrated unit, there are, in order from the one end portion to the other end portion, a first region in which a surface of the first sub-connection terminal facing the second sub-connection terminal and a surface of the second sub-connection terminal facing the first sub-connection terminal are in contact with each other, and a second region in which the distance in the first direction between the first sub-connection terminal and the second sub-connection terminal is constant. <1> The capacitor module according to claim 1 .

[0224] <6> When the first sub-connection terminal and the second sub-connection terminal are viewed as an integrated unit, the first region and the second region are continuously connected to each other. <5> The capacitor module according to claim 1 .

[0225] <7> a third region in which a distance between the first sub-connection terminal and the second sub-connection terminal in the first direction increases from the first region side toward the second region side when the first sub-connection terminal and the second sub-connection terminal are viewed as an integrated unit, the third region further exists so as to continuously connect between the first region and the second region; <5> The capacitor module according to claim 1 . [Explanation of symbols]

[0226] 1, 1', 2, 3 Capacitor Module 10 Capacitor element 10a First capacitor element 10b Second capacitor element 11 Base 12a 1st external electrode 12b 2nd external electrode 13a First metallized film 13b Second metallized film 14a First dielectric film 14aa: First main surface of first dielectric film 14ab: second main surface of first dielectric film 14b Second dielectric film 14ba: First main surface of second dielectric film 14bb: second main surface of second dielectric film 15a 1st metal layer 15b 2nd metal layer 20 Connection terminal 21a First main connection terminal 21b Second main connection terminal 22a 1st sub-connection terminal 22aa Surface of the first sub-connection terminal opposite to the second sub-connection terminal 22ab Surface of the first sub-connection terminal on the side of the second sub-connection terminal 22b Second sub-connection terminal 22ba Surface of the second sub-connecting terminal opposite to the first sub-connecting terminal 22bb Surface of the second sub-connecting terminal on the side of the first sub-connecting terminal 22c 3rd sub-connection terminal 22d 4th sub-connection terminal 31a 1st through hole 31b 2nd through hole D1 1st direction D2 2nd direction D3 Third direction P1: Dimension of the first through hole in the first direction Q1: The maximum distance in the first direction between the surface of the first sub-connecting terminal opposite the second sub-connecting terminal and the surface of the second sub-connecting terminal opposite the first sub-connecting terminal R1 1st area R2 2nd area R3 3rd area

Claims

1. a plurality of capacitor elements, each of which has an element body, a first external electrode provided on one end surface of the element body, and a second external electrode provided on the other end surface of the element body that faces the one end surface in a first direction; a plurality of connection terminals electrically connected to the plurality of capacitor elements; the plurality of capacitor elements include a first capacitor element and a second capacitor element adjacent to each other in the first direction such that the first external electrodes having the same polarity face each other while being spaced apart from each other; the multiple connection terminals include a first main connection terminal electrically connected to the first external electrodes of the first capacitor element and the second capacitor element at a position away from the first capacitor element and the second capacitor element, a first sub-connection terminal electrically connected to the first main connection terminal at one end side and electrically connected to the first external electrode of the first capacitor element at the other end side, and a second sub-connection terminal electrically connected to the first main connection terminal at one end side and electrically connected to the first external electrode of the second capacitor element at the other end side, The first main connection terminal is provided with a first through hole, a dimension of the first through hole in the first direction is smaller than a maximum distance in the first direction between a surface of the first sub-connection terminal opposite to the second sub-connection terminal and a surface of the second sub-connection terminal opposite to the first sub-connection terminal, A capacitor module characterized in that the first sub-connection terminal and the second sub-connection terminal pass through the first through hole with their one ends in contact with each other and their other ends spaced apart.

2. The capacitor module described in claim 1, wherein when the first sub-connection terminal and the second sub-connection terminal are viewed as an integrated unit, the distance in the first direction between the first sub-connection terminal and the second sub-connection terminal increases from the one end toward the other end.

3. The capacitor module according to claim 2 , wherein the first sub-connection terminal and the second sub-connection terminal each extend linearly.

4. The capacitor module according to claim 2 , wherein the first sub-connection terminal and the second sub-connection terminal each extend in a curved shape.

5. The capacitor module described in claim 1, wherein when the first sub-connecting terminal and the second sub-connecting terminal are viewed as an integrated unit, there are, in order from the one end toward the other end, a first region where a surface of the first sub-connecting terminal facing the second sub-connecting terminal and a surface of the second sub-connecting terminal facing the first sub-connecting terminal are in contact, and a second region in which the distance in the first direction between the first sub-connecting terminal and the second sub-connecting terminal is constant.

6. The capacitor module according to claim 5 , wherein when the first sub-connection terminal and the second sub-connection terminal are viewed as an integrated unit, the first region and the second region are continuously connected to each other.

7. The capacitor module described in claim 5, further comprising a third region in which, when the first sub-connection terminal and the second sub-connection terminal are viewed as an integrated unit, the distance in the first direction between the first sub-connection terminal and the second sub-connection terminal increases as the distance moves from the first region side to the second region side, and the third region further exists so as to continuously connect the first region and the second region.

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