Capacitor module

Abstract

A capacitor module of the present disclosure is provided with: one or more capacitor elements that have a pair of electrodes and a side surface that connects the pair of electrodes; a bus bar that is electrically connected to one of the pair of electrodes; a case that houses the one or more capacitor elements and a portion of the bus bar; and a sealing resin that fills the case and seals the one or more capacitor elements and the portion of the bus bar. The bus bar has a contact part that contacts the electrode and extends in a first direction; an extension part that is disposed along the side surface and extends in a second direction intersecting the first direction; and a connection part that connects the contact part and the extension part. The connection part has at least one of a first portion extending from an end of the contact part so as to be spaced apart from the electrode in the second direction, or a second portion extending from an end of the extension part so as to be spaced apart from the side surface in the first direction.

Description

Capacitor Module

[0001] The present disclosure relates to a capacitor module.

[0002] 2. Description of the Related Art A capacitor module is known that includes a capacitor element housed in a case and a bus bar connected to the capacitor element.

[0003] For example, Patent Document 1 discloses a bus bar structure of a capacitor having a capacitor element, a first bus bar, a second bus bar, an insulator, and a molding resin.

[0004] Japanese Patent Application Laid-Open No. 2021-153120

[0005] The capacitor of Patent Document 1 has a problem in that it is difficult to reduce the inductance.

[0006] The present disclosure provides a capacitor module that can reduce inductance.

[0007] A capacitor module according to one aspect of the present disclosure comprises: one or more capacitor elements each having a pair of electrodes and a side surface connecting the pair of electrodes; a bus bar electrically connected to one of the pair of electrodes; a case accommodating the one or more capacitor elements and a portion of the bus bar; and a sealing resin filled in the case and sealing the one or more capacitor elements and a portion of the bus bar, wherein the bus bar has a contact portion in contact with the electrode and extending in a first direction, an extension portion disposed along the side surface and extending in a second direction intersecting the first direction, and a connection portion connecting the contact portion and the extension portion, and the connection portion has at least one of a first portion extending from an end of the contact portion so as to be separated from the electrode in the second direction, or a second portion extending from an end of the extension portion so as to be separated from the side surface in the first direction.

[0008] According to the present disclosure, a capacitor module capable of reducing inductance can be provided.

[0009] 1 is a perspective view showing a capacitor element included in the capacitor module of FIG. 1; an enlarged view of region R1 of FIG. 1; an enlarged view of region R2 of FIG. 1; a cross-sectional view showing a capacitor module according to a first modified example of embodiment 1; a cross-sectional view showing a capacitor module according to a second modified example of embodiment 1; a cross-sectional view showing a capacitor module according to a second embodiment; an enlarged view of region R3 of FIG. 5; a cross-sectional view showing a capacitor module according to a third embodiment; an enlarged view of region R4 of FIG. 7;

[0010] (Background to the Disclosure) In capacitor modules, two bus bars are sometimes configured to face each other in order to reduce inductance. For example, in the capacitor disclosed in Patent Document 1, a pair of opposing plate portions of both bus bars are configured to face each other in close proximity. By facing the two bus bars, electric fields generated by currents flowing through the bus bars can be canceled out, thereby reducing the inductance of the capacitor module.

[0011] Furthermore, by bringing the side of the capacitor element as close as possible to the bus bar, the electric field generated by the current flowing through the capacitor element and the electric field generated by the current flowing through the bus bar can cancel each other out, thereby further reducing the inductance of the capacitor module.

[0012] If the busbar could be bent at a substantially right angle, it would be possible to bring the busbar close to both the electrodes of the capacitor element and the side surfaces of the capacitor element. However, because the busbar is made of a thin metal plate, the corners of the busbar may become locally rounded when it is bent. This rounded corner makes it difficult to bring the busbar into contact with the electrodes of the capacitor element and also to bring the busbar close to the side surfaces of the capacitor element.

[0013] In order to further reduce the inductance of the capacitor module, the inventors have investigated a bus bar structure that allows the bus bar to contact the electrodes of the capacitor elements and to be located close to the side surfaces of the capacitor elements, and have come to disclose the following.

[0014] A first embodiment of the present invention will be described below with reference to the accompanying drawings. In each drawing, each element is shown schematically for ease of explanation.

[0015] (Embodiment 1) [Overall Configuration] Fig. 1 is a cross-sectional view showing a capacitor module 100 according to embodiment 1. Fig. 2 is a perspective view showing a capacitor element 10 included in the capacitor module 100 of Fig. 1. Note that the X, Y, and Z directions in the figure indicate the horizontal, vertical, and height directions of the capacitor module 100, respectively.

[0016] 1 , capacitor module 100 includes capacitor element 10, bus bar 20, case 30, and sealing resin 40. In this embodiment, capacitor module 100 is formed by accommodating capacitor element 10 and a portion of bus bar 20 in case 30 and sealing with sealing resin 40 filled in case 30.

[0017] Each component of the capacitor module 100 will now be described.

[0018] <Capacitor Element> Capacitor element 10 is a film capacitor composed of a laminate of dielectric films. More specifically, capacitor element 10 is formed by stacking dielectric films each having a metal vapor deposition film formed on its surface, and then rolling or laminating the stack. In this embodiment, the rolled dielectric film is pressed into a flat shape, thereby forming capacitor element 10 into a columnar shape with an oval cross section.

[0019] The dielectric film may be formed, for example, from a mixed resin solution containing phenoxy resin and MDI (diphenylmethane diisocyanate). Alternatively, a dielectric film may be formed from a mixed resin solution containing polyvinyl acetoacetal (PVAA) and tolylene diisocyanate (TDI). Forming the dielectric film from such a mixed resin solution can increase the glass transition temperature of the dielectric film to 120°C or higher, thereby improving the heat resistance of the capacitor module. Metal vapor deposition films formed on the surface of the dielectric film may include metals such as Al and Zn.

[0020] A pair of electrodes 11, 12 for electrical connection to bus bar 20 is formed on both ends of the dielectric film laminate of capacitor element 10. Hereinafter, one of the pair of electrodes 11, 12 may be referred to as the first electrode 11, and the other as the second electrode 12. The electrodes 11, 12 can be formed by thermal spraying a metal (conductive material) such as Al or Zn.

[0021] 2 , capacitor element 10 has side surfaces 13 connecting a pair of electrodes 11, 12. In the present embodiment, capacitor element 10 is formed in a columnar shape having an oval cross section, and therefore side surfaces 13 of capacitor element 10 include a pair of flat portions 13 a and a pair of curved portions 13 b connecting the pair of flat portions 13 a.

[0022] <Case> Case 30 is a case for accommodating capacitor element 10. Case 30 has, for example, a substantially rectangular parallelepiped shape and has an opening 31 through which part of bus bar 20 is exposed. Capacitor element 10 is accommodated in case 30. In this embodiment, as shown in FIG. 1 , capacitor element 10 is disposed inside case 30 so that electrodes 11 and 12 face side wall 32 of case 30 and flat portion 13a of side surface 13 faces bottom wall 33 and opening 31 of the case. Part of bus bar 20 is also accommodated in case 30.

[0023] The case 30 is made of synthetic resin such as polyphenylene sulfide (PPS resin) or polybutylene terephthalate (PBT resin).

[0024] 1, sealing resin 40 is filled into case 30 to seal capacitor element 10 and a portion of bus bar 20 housed in case 30. Sealing resin 40 is made of a thermosetting resin such as epoxy resin or urethane resin. A material with high fluidity and adhesiveness may be used as the material for sealing resin 40.

[0025] <Busbar> Busbar 20 is connected to one of the pair of electrodes 11, 12 of capacitor element 10. Busbar 20 can be formed, for example, from a conductive metal plate. In this embodiment, busbar 20 includes a first busbar 21 connected to first electrode 11 and a second busbar 26 connected to second electrode 12.

[0026] First bus bar 21 has contact portion 22, extension portion 23, and connection portion 24. In the present embodiment, first bus bar 21 also has terminal portion 21a exposed to the outside of case 30.

[0027] The contact portion 22 extends in the first direction (Z direction) and contacts one of the first electrodes 11 of the capacitor element 10. The contact portion 22 electrically connects the first bus bar 21 and the first electrode 11 of the capacitor element 10.

[0028] The extension portion 23 is disposed along the side surface 13 of the capacitor element 10 and extends in a second direction (X direction) intersecting the first direction (Z direction). The extension portion 23 is disposed along the flat portion 13a of the side surface 13 of the capacitor element 10. The extension portion 23 is preferably disposed in contact with the flat portion 13a of the capacitor element 10. By disposing the extension portion 23 along the flat portion 13a, the electric field caused by the current flowing through the capacitor element 10 in the direction indicated by arrow A1 can be canceled out from the electric field caused by the current flowing through the first bus bar 21 in the direction indicated by arrow A2. Cancellation of the electric field of the capacitor element 10 and the electric field of the first bus bar 21 can contribute to reducing the inductance of the capacitor module 100. The shorter the distance between the extension portion 23 and the flat portion 13a, the greater the effect of reducing inductance. Therefore, it is preferable that the extension portion 23 and the flat portion 13a be in contact with each other.

[0029] 3A is an enlarged view of region R1 in FIG. 1 . As shown in FIG. 3A , the connection portion 24 is a portion that connects the contact portion 22 and the extension portion 23. In this embodiment, the connection portion 24 has a first portion 24a that extends from the end portion 22a of the contact portion 22 so as to be separated from the first electrode 11 in the second direction (X direction). Furthermore, in this embodiment, the connection portion 24 has a third portion 24b that extends between the first portion 24a and the extension portion 23 so as to approach the electrode 11 in the second direction (X direction). The first portion 24a extends from the end portion 22a of the contact portion 22 in the direction of arrow D1. The third portion 24b extends from the first portion 24a toward the extension portion 23 in the direction of arrow D2. In this embodiment, the connection portion 24 is disposed apart from the first electrode 11.

[0030] As shown in FIGS. 2 and 3A , at the intersection between the first electrode 11 of the capacitor element 10 and the flat portion 13a of the side surface 13, a corner c1 is formed by the extending surface of the first electrode 11 and the extending surface of the flat portion 13a. By aligning the position of the connection portion 24 with the corner c1 of the capacitor element 10, both the contact portion 22 and the extending portion 23 can be brought into contact with the capacitor element 10. As described above, because the bus bar 20 is formed of a metal plate, it is difficult to bend the bus bar 20 at a right angle so as to be able to contact both the first electrode 11 and the flat portion 13a of the capacitor element 10. In this embodiment, the positioning of the connection portion 24 can prevent interference between the corner c1 of the capacitor element 10 and the first bus bar 21. Therefore, a gap is prevented from occurring between the capacitor element 10 and the first bus bar 21, allowing both the contact portion 22 and the extending portion 23 to be brought into contact with the capacitor element 10.

[0031] In this embodiment, the connection portions 24 are curved. The curved connection portions 24 refer to the connection portions 24 being bent in an arch shape. This allows the connection portions 24 to function as springs and absorb the dimensional tolerances between the capacitor element 10 and the first bus bar 21. This ensures reliable contact between the contact portions 22 and the first electrodes 11, and between the extension portions 23 and the flat portions 13a, thereby reducing the inductance of the capacitor module 100.

[0032] 3B is an enlarged view of region R2 in FIG. 1 . As shown in FIG. 1 , second bus bar 26 is formed in a shape symmetrical to first bus bar 21 and is connected to second electrode 12. Therefore, second bus bar 26 has contact portion 27, extension portion 28, and connection portion 29. As shown in FIG. 3B , connection portion 29 of second bus bar 26 has first portion 29a extending from end 27a of contact portion 27 so as to be separated in the second direction (X direction) relative to second electrode 12. Furthermore, in this embodiment, connection portion 29 has third portion 29b extending between first portion 29a and extension portion 28 so as to approach electrode 1 in the second direction (X direction). First portion 29a extends from end 27a of contact portion 27 in the direction of arrow D3. Third portion 29b extends from first portion 29a toward extension portion 28 in the direction of arrow D4. In this embodiment, the connection portion 29 is disposed apart from the second electrode 12 .

[0033] 1 through the extending portion 28 of the second bus bar 26. Therefore, electric fields can be cancelled out between the extending portion 28 and the capacitor element 10 as well.

[0034] 1, the terminal portion 21a of the first bus bar 21 and the terminal portion 26a of the second bus bar 26 are arranged to overlap each other. An insulator (not shown) is arranged between the terminal portion 21a and the terminal portion 26a. By arranging the terminal portion 21a and the terminal portion 26a to overlap each other, the inductance of the capacitor module 100 can be reduced.

[0035] [Effects] According to the above-described embodiment, the following effects can be achieved.

[0036] The capacitor module 100 includes a capacitor element 10, a bus bar 20, a case 30, and a sealing resin 40. The capacitor element 10 has a pair of electrodes 11, 12 and a side surface 13 connecting the pair of electrodes 11, 12. The bus bar 20 is electrically connected to one of the pair of electrodes 11, 12. The case 30 accommodates the capacitor element 10 and a portion of the bus bar 20. The sealing resin 40 fills the case 30 and seals the capacitor element 10 and a portion of the bus bar 20. The bus bar 20 has contact portions 22, 27, extension portions 23, 28, and connection portions 24, 29. The contact portions 22, 27 contact the electrodes 11, 12 and extend in a first direction. The extension portions 23, 28 are arranged along the side surface 13 and extend in a second direction intersecting the first direction. The connecting portions 24, 29 connect the contact portions 22, 27 to the extending portions 23, 28. The connecting portion 24 has a first portion 24a that extends from the end portion 22a of the contact portion 22 so as to be spaced apart from the electrode 11 in the second direction.

[0037] With this configuration, the bus bar 20 can be brought into contact with the electrodes 11, 12 of the capacitor element 10 while also being close to the side surface of the capacitor element 10. This makes it possible to provide a capacitor module 100 with reduced inductance.

[0038] The connecting portion 24 has a third portion 24b extending between the first portion 24a and the extending portion 23 so as to approach the electrode 11 in the second direction.

[0039] With this configuration, the dimensional tolerance between capacitor element 10 and bus bar 20 can be accommodated, and bus bar 20 can be easily brought into contact with electrode 11 and side surface 13 .

[0040] The connecting portion 24 is curved.

[0041] With this configuration, the connection portions 24 and 29 can function as springs, making it easier for the bus bar 20 to come into contact with the electrode 11 and the side surface 13 .

[0042] The extensions 23 and 28 are in contact with the side surface 13 of the capacitor element 10 .

[0043] This configuration can enhance the effect of reducing inductance. Furthermore, even if the dimensional accuracy of capacitor element 10 is low, bus bar 20 can be brought into contact with electrodes 11 and 12, and bus bar 20 can be reliably aligned with side surface 13.

[0044] The busbar 20 includes a first busbar 21 electrically connected to one of the pair of electrodes 11, 12, the first electrode 11, and a second busbar 26 electrically connected to the other of the pair of electrodes 11, 12, the second electrode 12.

[0045] With this configuration, the electric field can be canceled out between the first bus bar 21 and the capacitor element 10, and between the second bus bar 26 and the capacitor element 10, thereby further improving the effect of reducing inductance.

[0046] [Modification] Fig. 4A is a cross-sectional view showing a capacitor module 100A according to a first modification of the first embodiment. As shown in Fig. 4A, of two bus bars 120, one (first bus bar 121) has a contact portion 122, an extension portion 123, and a connection portion 124. The other (second bus bar 126) of the two bus bars 120 is formed in a flat plate shape. In the first modification of the first embodiment, the extension portion 123 of the first bus bar 121 is arranged so as to cover substantially the entire side surface from the first electrode 11 to the second electrode 12. Therefore, the same effects as those of the first embodiment can be achieved.

[0047] 4B is a cross-sectional view showing a capacitor module 100B according to Modification 2 of Embodiment 1. As shown in FIG. 4B , connection portion 224 of first bus bar 221 may be formed in a bent shape rather than a curved shape. Similarly, connection portion 229 of second bus bar 226 may be formed in a bent shape. "Connection portion 224 having a bent shape" means that connection portion 224 is formed in a bent shape.

[0048] In the above-described embodiment, the capacitor module 100 includes one capacitor element 10, but the present invention is not limited to this. The capacitor module 100 may include a plurality of capacitor elements 10.

[0049] (Embodiment 2) A capacitor module 200 according to embodiment 2 of the present disclosure will be described. In embodiment 2, differences from embodiment 1 will be mainly described. In embodiment 2, configurations that are the same as or equivalent to those in embodiment 1 will be described using the same reference numerals. Furthermore, in embodiment 2, descriptions that overlap with embodiment 1 will be omitted.

[0050] Fig. 5 is a cross-sectional view showing a capacitor module 200 according to embodiment 2. As shown in Fig. 5, embodiment 2 differs from embodiment 1 in that connection portion 324 of first bus bar 321 has second portion 324a that extends from end portion 322a of extension portion 323 so as to be spaced apart in the first direction (Z direction) relative to side surface 13. Note that second bus bar 326 also has a similar configuration.

[0051] 6 is an enlarged view of region R3 in FIG. 5 . As shown in FIG. 6 , the connection portion 324 of the first bus bar 321 has a second portion 324a that extends from the end portion 323a of the extension portion 323 so as to be separated in the first direction (Z direction) from the side surface 13. The connection portion 324 also has a fourth portion 324b that extends between the second portion 324a and the contact portion 322 so as to approach the side surface 13 in the first direction (Z direction). The second portion 324a extends from the end portion 323a of the extension portion 323 in the direction of arrow D5. The fourth portion 324b extends from the second portion 324a toward the contact portion 322 in the direction of arrow D6. In this embodiment, as shown in FIG. 6 , the connection portion 324 is disposed away from the side surface portion of the electrode 11 and the side surface 13 of the capacitor element 10.

[0052] 5 , the second bus bar 326 is connected to the second electrode 12. The second bus bar 326 has a contact portion 327, an extension portion 328, and a connection portion 329, and is formed in the same shape as the first bus bar 321.

[0053] [Effects] According to the above-described embodiment, the following effects can be achieved.

[0054] The connecting portion 324 has a second portion 324a that extends from the end portion 323a of the extending portion 23 in the first direction (Z direction) away from the side surface 13. The connecting portion has a fourth portion 324b that extends between the second portion 324a and the contact portion 322 and approaches the side surface 13 in the first direction (Z direction).

[0055] With this configuration, even if the dimensional accuracy of the capacitor element 10 is low, the bus bar 20 can be reliably brought into contact with the electrodes 11, 12 and side surface 13 of the capacitor element 10, thereby reducing the inductance of the capacitor module 300.

[0056] (Embodiment 3) A capacitor module 300 according to embodiment 3 of the present disclosure will be described. In embodiment 3, differences from embodiment 1 will be mainly described. In embodiment 3, configurations that are the same as or equivalent to those in embodiment 1 will be described using the same reference numerals. Furthermore, in embodiment 3, descriptions that overlap with embodiment 1 will be omitted.

[0057] Fig. 7 is a cross-sectional view showing a capacitor module 300 according to embodiment 4. Fig. 8 is an enlarged view of region R3 in Fig. 7 and Fig. 8. As shown in Fig. 7, embodiment 3 differs from embodiment 1 in that connection portion 424 of first bus bar 421 has both first portion 242a and second portion 242b.

[0058] 8 , the connection portion 424 of the first bus bar 421 has a first portion 424a spaced from the end 422a of the contact portion 422 in the second direction (X direction) relative to the electrode 11, and a second portion 424b spaced from the end 423a of the extension portion 423 in the first direction (Z direction) relative to the side surface 13. The connection portion 424 further has a fifth portion 424c extending from the first portion 424a toward the second portion 424b. That is, in the third embodiment, the connection portion 424 has the first portion 424a extending away from the electrode 11, the second portion 424b extending away from the side surface 13, and the fifth portion 424c connecting the first portion 424a and the second portion 424b. As shown in FIG. 8 , in the present embodiment, the connection portion 424 is positioned so as not to contact the corner portion c1 of the capacitor element 10.

[0059] 7, the second bus bar 426 has a contact portion 427, an extension portion 428, and a connection portion 429. The connection portion 429 of the second bus bar 426 has a similar configuration to the connection portion 424 of the first bus bar 421.

[0060] [Effects] According to the above-described embodiment, the following effects can be achieved.

[0061] The connecting portion 424 has a first portion 424a and a second portion 424b. The connecting portion 424 has a fifth portion 424c extending from the first portion 424a toward the second portion 424b.

[0062] With this configuration, even if the dimensional accuracy of capacitor element 10 is low, bus bar 420 can be reliably contacted with electrodes 11 and 12, and bus bar 420 can be reliably contacted with side surface 13, thereby reducing the inductance of capacitor module 300.

[0063] In the above-described embodiment, the connecting portion 424 has both the first portion 424 a and the second portion 424 b, but the present invention is not limited to this. The connecting portion 424 may have at least one of the first portion 424 a and the second portion 424 b.

[0064] (Summary of Embodiments) (1) A capacitor module according to the present disclosure includes one or more capacitor elements each having a pair of electrodes and a side surface connecting the pair of electrodes; a bus bar electrically connected to one of the pair of electrodes; a case accommodating the one or more capacitor elements and a portion of the bus bar; and a sealing resin filled in the case and sealing the one or more capacitor elements and the portion of the bus bar, wherein the bus bar has a contact portion that contacts the electrode and extends in a first direction, an extension portion that is disposed along the side surface and extends in a second direction that intersects the first direction, and a connection portion that connects the contact portion and the extension portion, and the connection portion has at least one of a first portion that extends from an end of the contact portion so as to be away from the electrode in the second direction, or a second portion that extends from an end of the extension portion so as to be away from the side surface in the first direction.

[0065] (2) In the capacitor module of (1), the connection portion may have a first portion.

[0066] (3) In the capacitor module of (2), the connection portion may have a third portion extending between the first portion and the extension portion so as to approach the electrode in the second direction.

[0067] (4) In the capacitor module of (1), the connection portion may have a second portion.

[0068] (5) In the capacitor module of (4), the connecting portion may have a fourth portion between the second portion and the contact portion, the fourth portion extending toward the side surface in the first direction.

[0069] (6) In the capacitor module of (1), the connection portion may have a first portion and a second portion.

[0070] (7) In the capacitor module of (6), the connection portion may have a fifth portion extending from the first portion toward the second portion.

[0071] (8) In the capacitor module of any one of (1) to (7), the connection portion may be curved.

[0072] (9) In the capacitor module of any one of (1) to (8), the extension and the side surface of the capacitor element may be in contact with each other.

[0073] (10) In the capacitor module of any one of (1) to (9), the bus bar may include a first bus bar electrically connected to one of the pair of electrodes, a first electrode, and a second bus bar electrically connected to the second electrode of the pair of electrodes.

[0074] The present disclosure is useful for capacitor modules used in various electronic devices, electrical devices, industrial devices, vehicle devices, etc.

[0075] REFERENCE SIGNS LIST 1 Electrode 10 Capacitor element 11 First electrode (electrode) 12 Second electrode (electrode) 13 Side surface 13a Flat portion 20, 120, 220, 320, 420 Bus bar 21, 121, 221, 321, 421 First bus bar 22, 122, 222, 322, 422 Contact portion 23, 123, 223, 323, 423 Extension portion 24, 124, 224, 324, 424 Connection portion 26, 126, 226, 326, 426 Second bus bar 27, 227, 327, 427 Contact portion 28, 228, 328, 428 Extension portion 29, 229, 329, 429 Connection portion 30 Case 40 Sealing resin 100, 100A, 100B, 200, 300 Capacitor Module

Claims

1. A capacitor module comprising: one or more capacitor elements each having a pair of electrodes and a side surface connecting the pair of electrodes; a bus bar electrically connected to one of the pair of electrodes; a case accommodating the one or more capacitor elements and a portion of the bus bar; and a sealing resin filled into the case and sealing the one or more capacitor elements and a portion of the bus bar, wherein the bus bar has a contact portion in contact with the electrode and extending in a first direction, an extension portion disposed along the side surface and extending in a second direction intersecting the first direction, and a connection portion connecting the contact portion and the extension portion, and the connection portion has at least one of a first portion extending from an end of the contact portion so as to be separated in the second direction from the electrode, or a second portion extending from an end of the extension portion so as to be separated in the first direction from the side surface.

2. The capacitor module according to claim 1, wherein the connection portion has the first portion.

3. The capacitor module according to claim 2, wherein the connection portion has a third portion that extends between the first portion and the extension portion so as to approach the electrode in the second direction.

4. The capacitor module according to claim 1, wherein the connection portion has the second portion.

5. The capacitor module according to claim 4, wherein the connection portion has a fourth portion extending closer to the side surface in the first direction between the second portion and the contact portion.

6. The capacitor module according to claim 1, wherein the connection portion has the first portion and the second portion.

7. The capacitor module according to claim 6, wherein the connection portion has a fifth portion extending from the first portion toward the second portion.

8. A capacitor module according to any one of claims 1 to 7, wherein the connection portion is curved.

9. The capacitor module according to claim 1, wherein the extension and a side surface of the capacitor element are in contact with each other.

10. A capacitor module according to any one of claims 1 to 9, wherein the bus bars include a first bus bar electrically connected to a first electrode of one of the pair of electrodes, and a second bus bar electrically connected to a second electrode of the other of the pair of electrodes.

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