Folded membrane carrier for battery case ventilation

Abstract

A vent unit (34) for a battery housing, the vent unit (34) comprising: a housing part (36) defining a vent opening (38); and a membrane assembly (10; the invention relates to a diaphragm assembly (10, 10 '), which spans a vent opening (38) and comprises a diaphragm carrier (12, 12'), which diaphragm carrier (12, 12 ') comprises carrier sections (14) and flow windows (16) respectively provided by the carrier sections (14), and diaphragm sections (18), which diaphragm sections (18) respectively cover the flow windows (16). Each adjacent pair of carrier sections (14) are folded against each other along a sheet hinge (20) provided between them.

Description

Technical Field

[0001] The embodiments relate to a venting unit for a battery casing, the venting unit including a housing component defining a vent opening and a diaphragm assembly spanning the vent opening. Background Technology

[0002] Such ventilation units are generally known.

[0003] The internal pressure of battery casings, especially those used in traction batteries for electric vehicles, typically needs to be balanced with ambient pressure to avoid damage. Simultaneously, it is necessary to prevent dust or water from entering the battery casing, such as during use on gravel roads or during high-pressure cleaning. For this purpose, a venting unit with a diaphragm is employed.

[0004] In the event of thermal runaway, the explosion of the battery casing can be prevented by an emergency degassing unit, which has a spring-loaded valve or a burst diaphragm. These emergency degassing units typically have a fairly high activation pressure (e.g., at least 250 mbar) and remain open once triggered.

[0005] Sometimes, only one or a few battery cells fail. In this case, a moderate amount of gas and pressure (typically 70-90 mbar, sometimes up to 120 mbar) is generated and needs to be released. This is called a “cold venting.” In this situation, the battery can be repaired if necessary. However, the amount of gas to be released during a cold venting event cannot be depressurized by conventional venting units because their diaphragm area is too small. Increasing the diaphragm area is generally not possible due to the limited installation space at the battery casing. On the other hand, adapting emergency degassing units to cold venting would allow dust or water to intrude once activated. Furthermore, adapting spring-loaded valves to cold venting is not easy to implement because the pressure during a cold venting event is quite low, making it possible for the valve to open unintentionally under harsh operating conditions, such as when driving on gravel roads or hitting a pothole.

[0006] The purpose of this embodiment is to allow cold ventilation of the battery casing while preventing dust and water from entering the battery casing.

[0007] This is achieved by the ventilation unit according to claim 1, the battery casing according to claim 10, the battery according to claim 11, and the method according to claim 12. Advantageous embodiments and variations are given in the dependent claims and the specification. Summary of the Invention

[0008] According to an embodiment, a venting unit for a battery casing is provided. The venting unit includes a housing component defining a vent opening. In use, the vent opening can be aligned with an opening in the battery casing. The venting unit also includes a diaphragm assembly spanning the vent opening. The diaphragm assembly allows gas to exit or enter through the vent opening while blocking water and dust.

[0009] According to an embodiment, the diaphragm assembly includes a diaphragm carrier comprising carrier segments and flow windows respectively disposed through the carrier segments. The diaphragm assembly also includes diaphragm segments respectively covering the flow windows. Typically, a separate diaphragm segment is provided for each flow window. However, in certain embodiments, the diaphragm segments for some or all of the flow windows may also be monolithic. Typically, each carrier segment provides one flow window. However, it is also conceivable to provide several flow windows for each carrier segment. In the latter case, all flow windows of a carrier segment are typically covered by one diaphragm segment.

[0010] The diaphragm carrier has sheet hinges (also known as integral hinges) between adjacent carrier sections. Each adjacent pair of carrier sections folds against each other along the sheet hinges between them. By folding the diaphragm carrier at the sheet hinges between its carrier sections, the diaphragm is erected in a direction perpendicular to the diameter or width of the vent opening. This allows for an increase in the total area available for gas exchange. While the area of ​​a conventional flat diaphragm is limited by the area of ​​the vent opening, the folded diaphragm assembly provides a total area of ​​flow windows (i.e., the diaphragm area available for gas exchange) exceeding the area of ​​the vent opening. With this design, the volume of gas generated during a cold venting event can be released from the battery housing through orifices of a conventional venting unit size. The diaphragm sections are designed to remain intact during such cold venting events. Therefore, the housing remains sealed against dust or water in the environment.

[0011] The total area of ​​the flow windows can be at least 1.3 times larger than the cross-sectional area of ​​the vent openings, and particularly at least 1.5 times larger. Therefore, a relatively high ventilation volume can be achieved using small orifices and corresponding small vent openings in the housing.

[0012] The diaphragm segment can be made of polytetrafluoroethylene, particularly sintered polytetrafluoroethylene. Alternatively, the diaphragm segment can be made of polyethylene terephthalate (PET) or other perfluoroalkyl and polyfluoroalkyl substances (PFAS) and perfluorooctanoic acid (PFOA), free diaphragm materials.

[0013] The diaphragm carrier is generally a single piece of plastic. The diaphragm carrier can be made of, for example, polypropylene.

[0014] Typically, at least four, and particularly at least six, carrier segments are provided. Note that in most embodiments, an even number of carrier segments are provided. This is advantageous for sealing the end segments of the diaphragm carrier against the housing components, as two end segments can be sealed in the same plane. Each end segment can be linked to the corresponding outermost carrier segment via a sheet hinge.

[0015] The periphery of the diaphragm carrier can be embedded into the housing component. This creates a strong and watertight connection between the housing component and the diaphragm carrier. For efficient manufacturing, the housing component can be injection molded onto the diaphragm carrier. To do this, after attaching and folding the diaphragm section, the diaphragm carrier is placed in a mold used to manufacture the housing component. In other words, the folded diaphragm assembly is an insert when molding the housing component.

[0016] The diaphragm sections can be welded to the carrier sections individually around the flow window, particularly via ultrasonic welding, hot plate welding, or heat sealing. This allows for efficient manufacturing. Furthermore, watertight connections can be achieved.

[0017] In this embodiment, each adjacent pair of carrier segments can be directly connected to each other via sheet-like hinges. In this case, when the diaphragm assembly is mounted in the housing component, adjacent diaphragm segments form an acute angle. A particularly simple design for the diaphragm carrier and a large total area of ​​the flow window can be achieved.

[0018] In other embodiments, the diaphragm carrier may further include intermediate sections, each of which is disposed between corresponding adjacent pairs of carrier sections and connected to the corresponding adjacent pairs of carrier sections via sheet hinges. This design reduces the bending angle at each sheet hinge, which prevents damage (and leakage) at the sheet hinges. With this design, when the diaphragm assembly is mounted in the housing component, the diaphragm sections can be arranged parallel to each other, particularly perpendicular to the width of the vent opening.

[0019] Each sheet hinge typically comprises a slit in one surface of the diaphragm carrier and a groove in the opposite surface. Between the slit and the groove, the material of the diaphragm carrier is continuous. Therefore, the sheet hinge itself is both airtight and watertight. The continuous material layer forms a sheet that is bent when the diaphragm carrier is folded.

[0020] The sheet hinges are arranged to bend in alternating directions, i.e., having slits and grooves on different sides of the diaphragm carrier. If adjacent carrier segments with flow windows are directly connected to each other by a sheet hinge, the orientation of the sheet hinge changes from one sheet hinge to the next. If intermediate segments of the diaphragm carrier are arranged between adjacent carrier segments with flow windows, wherein the intermediate segments are connected to two adjacent carrier segments by sheet hinges, then a pair of sheet hinges at one intermediate segment are oriented in the same direction, while the next pair of sheet hinges faces the opposite direction.

[0021] Vent openings can have a circular cross-section. This is advantageous for manufacturing venting units, for example, because it eliminates the need to ensure a specific rotational orientation of the folded separator assembly during overmolding of the housing components. Furthermore, orifices in battery casings often need to be circular. Therefore, circular vent openings allow for efficient utilization of the orifice area for venting.

[0022] The venting unit may also include a base body in which housing components are fixed. The base body may be designed for attachment to a battery casing. A seal may be provided at the base body for sealing against the battery casing. By adapting the base body to a corresponding battery casing, the same diaphragm assembly and housing components can be used, each with a different interface at the corresponding battery casing, namely the base body.

[0023] If supplied, the housing components are typically fixed to the base body by rotary welding (rotary friction welding). This allows for efficient manufacturing. Furthermore, watertight connections can be reliably achieved through rotary welding.

[0024] The venting unit may also include a cover that is attached to the housing component or base body. The cover protects the diaphragm section from damage, such as during high-pressure cleaning or when debris impacts the venting unit. The cover can be attached by ultrasonic welding. Alternatively, a snap-fit ​​engagement can be established.

[0025] The embodiments also relate to a battery housing that includes an opening and a venting unit disposed at the opening of the battery housing, as described above.

[0026] An emergency degassing unit can be located at another opening in the housing. The housing can have several additional openings, each equipped with an emergency degassing unit, especially when only one ventilation unit is provided.

[0027] The embodiments also relate to a battery comprising a battery casing as described above, and further comprising battery cells disposed inside the battery casing. The battery cells may be lithium-ion cells. Although lithium-ion cells have several well-known advantages, they are prone to failure if poorly manufactured or subjected to excessive mechanical loads. Obviously, other types of battery cells can also be considered.

[0028] Finally, the embodiments relate to a method of manufacturing a ventilation unit as described above. The method includes: A) providing a diaphragm carrier including carrier segments and flow windows; B) covering the flow windows with diaphragm segments respectively and fixing the diaphragm segments to the carrier segments respectively; C) folding the diaphragm carrier between each adjacent pair of carrier segments; and D) molding a housing component around the folded diaphragm carrier.

[0029] Steps A) through D) are generally performed in the indicated order.

[0030] The diaphragm carrier is typically configured as a flat plastic component. Sheet hinges can be pre-formed in the flat diaphragm carrier between its carrier segments.

[0031] In step B), individual diaphragm segments can be arranged at the flow windows and individually fixed around each flow window. Alternatively, a larger sheet of diaphragm material can be provided and arranged to cover all flow windows. In the latter case, the monolithic sheet of diaphragm material is typically cut between the flow windows, for example, by stamping, to form separate diaphragm segments. Ultrasonic welding can be used to connect the diaphragm segments and the diaphragm carrier. The stamping tool can be incorporated into the ultrasonic welding tool. Thus, in a one-step process, a single sheet of diaphragm material can be separated to form several diaphragm segments while being fixed to the carrier.

[0032] At each carrier segment, a continuous closed connection between the diaphragm segment and the diaphragm carrier is established around the corresponding flow window (or multiple flow windows, if each carrier segment provides more than one flow window). Several flow windows in each carrier segment can be surrounded jointly or individually by lines fixed to the diaphragm segment.

[0033] Note that for folding at the convex hinge (in the view on the diaphragm-covered side of the carrier), the diaphragm needs to be largely separated because the diaphragm material may not be able to withstand stretching to the required extent. At the concave hinge, one diaphragm segment can cover the flow windows of two adjacent carrier segments. However, for folding the carrier, a separate diaphragm segment for each carrier segment is advantageous.

[0034] After folding, the diaphragm assembly (i.e., a carrier having a diaphragm segment fixed around the flow window) is inserted into a mold for manufacturing the shell components. By molding the shell components to the periphery of the diaphragm carrier, molecular bonds can be established between these components.

[0035] The method may also include E) testing the water tightness of the diaphragm assembly molded to cover the housing component. Therefore, in one test step, it can be determined whether the connections between the diaphragm carrier and the housing component, as well as all connections between the diaphragm carrier and the diaphragm section, have been correctly manufactured and are leak-free.

[0036] The method may also include F) attaching the housing component to the base body, particularly by spin welding. Note that the watertightness test is advantageously performed before the base body is installed. With spin welding, leakage is extremely unlikely. Furthermore, since the same design of the housing component and the diaphragm assembly can be used with different base bodies, it is sufficient to provide a test apparatus suitable for the design of the housing component.

[0037] To protect the diaphragm assembly, the method may further include G) attaching a cover to the housing component or base body. Note that the cover may be installed before, during, or after attachment to the base body. Watertightness testing is advantageously performed before the cover is installed. Attached Figure Description

[0038] Other advantages and features of the embodiments will be understood from the following description of the embodiments, which shows important details in the accompanying drawings, and from the claims. The various features described above or explained below may be implemented individually or together in any useful combination in variations of the embodiments.

[0039] Figure 1 A diaphragm assembly for use in an embodiment is shown in a schematic perspective view. The diaphragm assembly includes a folded diaphragm carrier having attached diaphragm segments.

[0040] Figure 2 A schematic cross-sectional view is shown. Figure 1 diaphragm assembly.

[0041] Figure 3 An enlarged schematic diagram along its folding axis is shown. Figure 1 The sheet-like hinge of the diaphragm carrier of the diaphragm assembly.

[0042] Figure 4 A schematic cross-sectional view is shown of a ventilation unit according to an embodiment, the ventilation unit comprising components embedded in a housing member. Figure 1 diaphragm assembly.

[0043] Figure 5 A schematic perspective view shows the component attached to the base. Figure 4 The ventilation unit.

[0044] Figure 6 Show Figure 5 A schematic cross-sectional view of the component.

[0045] Figure 7 A schematic perspective view showing a cover with attachments. Figure 5 Components.

[0046] Figure 8 Show Figure 7 A schematic cross-sectional view of the component.

[0047] Figure 9 A schematic diagram illustrating a battery according to an embodiment is provided.

[0048] Figure 10 Another diaphragm assembly used in the embodiment is shown in a schematic cross-sectional view, which includes a folded diaphragm carrier having attached diaphragm segments.

[0049] Figure 11A schematic flowchart of a manufacturing method according to an embodiment is shown. Detailed Implementation

[0050] Figure 1 and Figure 2 The diaphragm assembly 10 is shown. The diaphragm carrier 12 includes a plurality of carrier segments 14, each carrier segment 14 having a flow window 16. Each flow window 16 is covered by a diaphragm segment 18.

[0051] The diaphragm section 18 may be composed of sintered polytetrafluoroethylene. The thickness of the diaphragm section 18 may be between 0.02 mm and 0.2 mm.

[0052] The diaphragm carrier can be a one-piece injection-molded component made of, for example, polypropylene.

[0053] The diaphragm section 18 is specifically attached to the carrier section 14 by ultrasonic welding. A sealed joint is established around the flow window 16 and the periphery of the diaphragm section 18.

[0054] Adjacent carrier segments 14 are connected to each other by sheet hinges 20. The diaphragm carrier 12 is folded along the sheet hinges 20. This results in the three-dimensional shape of the diaphragm assembly 10. In these embodiments, adjacent diaphragm segments 18 and carrier segments 14 form an acute angle 22. For example, the angle 22 can be between 25° and 50°.

[0055] The end sections 24 of the diaphragm carrier 12 are connected to its two outermost carrier sections 14 by additional sheet-like hinges 26. The end sections 24 are completely closed, i.e., they have no flow windows or attached diaphragm sections. The two end sections 24 extend in a common plane.

[0056] Figure 3 One of the folded sheet hinges 20 is shown. To form the sheet hinge 20, the material of the diaphragm carrier 12 is locally thinned, such that a sheet of continuous material extends between adjacent carrier segments 14. A slit 28 is introduced from the convex side of the sheet hinge 20, the slit 28 having a face 30 that is separated from each other in the folded state. A groove 32 is provided on the concave side of the sheet hinge 20.

[0057] Figure 4 A ventilation unit 34 including a diaphragm assembly 10 is shown. The folded diaphragm assembly 10 is embedded in a housing component 36. The housing component 36 is securely bonded to the outer periphery of the diaphragm carrier 12, i.e., the free edges of the carrier section 14 and the end section 24, using an overmolding technique.

[0058] The diaphragm assembly 10 spans the diameter 37 of the vent opening 38 defined by the housing component 36. In these embodiments, the vent opening 38 has a circular cross-section. Due to the folding of the diaphragm carrier 12, the flow window 16 and the diaphragm segment 18 are inclined relative to the axis 40 of the vent opening 38. Therefore, the total area of ​​the flow window 16 covered by the diaphragm exceeds the cross-sectional area of ​​the vent opening 38 (measured perpendicular to the axis 40). In these embodiments, the total area of ​​the flow window 16 is greater than 1.6 times the cross-sectional area of ​​the vent opening 38.

[0059] like Figure 5 and Figure 6 As shown, the base body 42 can be attached to the housing component 36 of the ventilation unit 34. A circumferentially closed connection 44 can be obtained using rotary welding technology.

[0060] The base body 42 has an attachment tab 45 for securing the venting unit 34 to the battery housing 46, for example, by passing a screw through the attachment tab 45. See [link to relevant documentation] Figure 9 .

[0061] The seal 48 can be located at the base body 42. In the installed state, the seal 48 surrounds the orifice 50 to seal the venting unit 34 against the battery casing 46.

[0062] Cover 52 is disposed above the diaphragm assembly 10 (i.e., on the side facing away from the battery housing 46) to protect the diaphragm section 18 from damage, see [reference]. Figure 7 and Figure 8 In these embodiments, the cover 52 is attached to the housing component 36, for example, by ultrasonic welding. Airflow between the cover 52 and the housing component 36 is allowed through the opening 54.

[0063] like Figure 9 As depicted, battery 56 is obtained by arranging battery cells 58 (e.g., lithium-ion cells) inside battery casing 46.

[0064] Ventilation unit 34 at orifice 50 allows for pressure equalization between the internal space 60 of battery housing 46 and the environment 62. If one (or more) of battery cells 58 may fail, the amount of gas generated in a so-called cold venting event is released through ventilation unit 34. After a cold venting event, ventilation unit 34 (and therefore battery housing 46) remains sealed by diaphragm section 18. Internal space 60 remains protected from dust and water intrusion.

[0065] In the event of thermal runaway, when many or all of the battery cells 58 fail and eventually catch fire, hot gases are released into the environment 62 through one or more emergency degassing units 64. If the activation threshold of the emergency degassing units 64 is exceeded, they open and typically do not close again.

[0066] Figure 10 Another diaphragm assembly 10' is shown. (See diagram.) Figure 1 and Figure 2 The diaphragm assembly 10 depicted includes a diaphragm carrier 12' having a carrier section 14. A diaphragm section 18 covers a flow window 16 of the carrier section 14. Similarly, the diaphragm assembly 10' is mounted within a housing component 36 to form a venting unit 34, as referenced above. Figures 4 to 9 As described.

[0067] exist Figure 10 In one embodiment, the diaphragm carrier 12' has a middle section 66 connected to an adjacent carrier section 14 via a sheet-like hinge 20. In the folded state, the carrier section 14 and the diaphragm section 18 can extend parallel to each other and parallel to the axis 40 of the vent opening 38 (see also...). Figure 4 The sheet hinges 20 and 26 between the outermost carrier section 14 and the end section 24 can be referenced as above. Figure 3 The design described.

[0068] Additional reference Figure 11 A method for manufacturing a ventilation unit 34 having a diaphragm assembly 10 or 10' is described.

[0069] First, diaphragm carriers 12 and 12' are provided as flat plastic components (see step 102). Flow windows 16 and sheet hinges 20 and 26 are already present in the monolithic body of diaphragm carriers 12 and 12'.

[0070] Next, the diaphragm segments 18 are arranged to cover the flow windows 16 (see step 104), and circumferential closed connections are established between the diaphragm segments 18 and the flow windows 16 of each carrier segment 14 (see step 106). This can be done using ultrasonic welding. During welding, the monolithic diaphragm sheets can also be separated to form separate diaphragm segments 18. Alternatively, separate diaphragm segments 18 can be provided in step 104.

[0071] Next, the diaphragm carriers 12, 12' with attached diaphragm segments 18 are folded at their sheet hinges 20, 26 (see step 108). The folding yields a three-dimensional configuration of the diaphragm assembly 10.

[0072] The folded diaphragm assembly 10 is placed in a mold for injection molding the housing component 36. The housing component 36 is formed by injection molding of a plastic material (see step 110). Diaphragm carriers 12, 12' are embedded and bonded to the housing component 36 along their peripheries and vent openings 38. Specifically, the diaphragm carriers 12, 12' are tightly bonded to the housing component 36. Advantageously, molecular bonds are established between the diaphragm carriers 12, 12' and the housing component 36.

[0073] The watertightness of the ventilation unit 34 produced in step 110 can be tested in step 112. Therefore, in a single test step, it is verified whether all diaphragm carrier connections and carrier-shell connections meet their requirements.

[0074] Finally, the base body 42 and cover 52 can be installed, referring to steps 114 and 116. Note that there is generally no specific order for installing the base body 42 and cover 52. In mass production, different base bodies can be provided to adapt the same housing components to specific battery cases.

[0075] In summary, the embodiments relate to a venting unit for a battery casing. A casing component defines a vent opening having an open cross-section and an axis perpendicular to that cross-section. The cross-section of the vent opening is covered by a diaphragm assembly. The diaphragm assembly has a three-dimensional configuration extending along its axis. Diaphragm segments are arranged at an angle relative to the cross-section of the vent opening. This allows for an open diaphragm area exceeding the cross-sectional area of ​​the vent opening. A diaphragm carrier holding the diaphragm segments in their upright configuration is folded along sheet hinges to define the three-dimensional configuration. The sheet hinges are disposed between carrier segments, each carrier segment having a flow opening covered by a diaphragm segment.

[0076] List of reference numerals Diaphragm assembly 10; 10' Diaphragm carrier 12; 12' Carrier segment 14 Flow window 16 Diaphragm section 18 20-piece hinge Angle 22 End section 24 26-piece hinge Slit 28 30 Groove 32 Ventilation unit 34 37 in diameter Housing component 36 Ventilation opening 38 Axis 40 Base body 42 Connecting part 44 Attached tongue 45 Battery casing 46 Seal 48 50mm orifice Cover part 52 Hole 54 Battery 56 Battery cell 58 Interior space 60 Environment 62 Emergency degassing unit 64 Middle section 66 Provide 102 membrane carrier Covering 104 flow windows Fixed 106 diaphragm section Folded 108 diaphragm carrier Molded 110 housing components Test 112 water tightness Attached 114 housing components Attached 116 cover

Claims

1. A venting unit (34) for a battery casing, the venting unit (34) comprising: Housing component (36), the housing component (36) defines a vent opening (38); and Diaphragm assembly (10; 10'), the diaphragm assembly (10; 10') spans the ventilation opening (38) and includes: A diaphragm carrier (12; 12'), the diaphragm carrier (12; 12') comprising a carrier segment (14) and flow windows (16) respectively disposed through the carrier segment (14); and Diaphragm sections (18) cover the flow windows (16). In this configuration, each adjacent pair of carrier segments (14) folds against each other along the sheet-like hinges (20) between them.

2. The ventilation unit (34) according to claim 1, wherein, The periphery of the diaphragm carrier (12; 12') is embedded in the shell component (36).

3. The ventilation unit (34) according to claim 1 or 2, wherein, The diaphragm section (18) is welded to the carrier section (14) around the flow window (16).

4. The ventilation unit (34) according to any one of claims 1 to 3, wherein, Each adjacent pair of carrier segments (14) are directly connected to each other by sheet-like hinges (20).

5. The ventilation unit (34) according to any one of claims 1 to 3, wherein, The diaphragm carrier (12') also includes intermediate sections (66), each of which is disposed between corresponding adjacent pairs of carrier sections (14) and connected to the corresponding adjacent pairs of carrier sections (14) by sheet hinges (20).

6. The ventilation unit (34) according to any one of the preceding claims, wherein, The total area of ​​the flow window (18) is at least 1.3 times larger than the cross-sectional area of ​​the ventilation opening (38), and in particular at least 1.5 times larger.

7. The ventilation unit (34) according to any one of the preceding claims, wherein, The ventilation opening (38) has a circular cross-section.

8. The ventilation unit (34) according to any one of the preceding claims further includes a base body (42), and a housing component (36) is fixed in the base body.

9. The ventilation unit (34) according to any one of the preceding claims further includes a cover (52) fixed to the housing component (36) or the base body (42).

10. A battery casing (46), comprising: Orifice (50); and The ventilation unit (34) is provided at the orifice (50) according to any one of the preceding claims.

11. A battery (56), comprising: The battery casing (46) according to claim 10, and Battery unit (58) is disposed inside the battery casing (46).

12. A method of manufacturing a ventilation unit (34) according to any one of claims 1 to 9, the method comprising: A) Provides (102) a diaphragm carrier (12; 12'), the diaphragm carrier (12; 12') including a carrier segment (14) and a flow window (16); B) Use the diaphragm section (18) to cover (104) the flow window (16) respectively, and fix (106) the diaphragm section (18) to the carrier section (14) respectively. C) Fold (108) the diaphragm carrier (12; 12') between each adjacent pair of carrier segments (14); and D) Molding (110) shell components (36) around the folded diaphragm carrier (12; 12').

13. The method of claim 12 further includes E) testing the water tightness of the diaphragm assembly (10; 10') overmolded with the housing component (36) by the (112) method.

14. The method according to claim 12 or 13 further includes F) attaching (114) the housing component (36) to the base body (42), particularly by rotational welding.

15. The method according to any one of claims 12 to 14, further comprising G) attaching (116) the cover (52) to the housing component (36) or the base body (42).

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