Pressure equalizing device for battery case

Abstract

The invention relates to a pressure equalization device (1, 201, 301, 401) for a battery housing. The device comprises: a cage (2, 202, 302, 402), the cage defining a fluid passage (23, 223, 323, 423); a cover (4, 204, 304, 404) mounted on the cage frame; and a membrane (34, 234, 334, 434) covering the fluid passage to equalize a pressure inside the housing with an ambient pressure outside the housing. The cover is movable during use between an open configuration in which air may escape and a closed configuration in which the housing is sealed.

Description

Technical Field

[0001] The invention relates to the field of pressure equalization devices making it possible to compensate for pressure variations inside a battery and to systematically release the pressure (for example by means of a degassing device) in the event of an overpressure. Background Art

[0002] The use of a pressure compensation element for an accumulator is known from patent EP 3385584 filed by Freudenberg. More precisely, this element has not only the function of pressure compensation in normal operation, but also the function of reducing overpressure during emergency degassing. Summary of the invention

[0003] The invention relates to a pressure equalizing device for a battery casing.

[0004] The device may include a cage. The cage may define a fluid passage. Advantageously, the device may include a cover, which may be mounted on the cage. The cover may be, for example, movable between an open configuration, in which air may escape from the housing during use, and a closed configuration, in which the housing is sealed.

[0005] The invention also relates to a pressure equalization device for a housing, comprising a cage defining a fluid passage and a cover mounted on the cage, characterized in that the cover is movable during use between an open configuration, characterized in that air can escape, and a closed configuration, in which the housing is sealed.

[0006] The device may include a membrane that may cover the fluid passage, for example to equalize the pressure inside the housing with the ambient pressure outside the housing.

[0007] The present invention also relates to a pressure equalization device for a housing, wherein the device comprises a cage defining a fluid passage, a cover mounted on the cage, and a membrane covering the fluid passage to equalize the pressure inside the housing with the ambient pressure outside the housing, wherein the cover is movable during use between an open configuration, in which air can escape, and a closed configuration, in which the housing is sealed.

[0008] The cover is rotatable between an open configuration or position and a closed configuration or position.

[0009] At least one of the cover and the cage may include a formation, such as an angled, spiral or threaded formation, that may cooperate with a formation on the other of the cover and the cage to move the cover relative to the cage when rotating between an open configuration or position and a closed configuration or position.

[0010] The lid may be screwed between an open configuration or position and a closed configuration or position.The device may include a sealing member on one or both of the lid and / or cage, for example, the sealing member seals the housing when the lid is in the closed configuration or position.

[0011] The cover may include one or more windows. The cage may include one or more windows. For example, when the cover is in an open position, the (or each) window of the cover may be aligned with a corresponding window of the cage. For example, when the cover is in a closed position, the (or each) window of the cover may be misaligned or staggered relative to one or more corresponding windows of the cage. The device may include a seal, such as a window seal, which may be configured to seal fluid exchange between the windows, such as when the cover is in a closed position.

[0012] The device may include a valve element, such as a flexible umbrella valve element. The valve element may cover a fluid passage. The valve element may include an orifice, such as through its thickness. The valve element may include a membrane or a membrane that may be attached to the valve element and / or may cover the orifice.

[0013] The valve element membrane can be configured to equalize the pressure inside the battery housing with the ambient pressure outside the battery housing during use. The valve element can be configured to move or deform in a reversible manner, for example, under a predetermined pressure difference between the inside and outside of the battery housing to prevent overpressure from forming inside the battery housing.

[0014] The present invention thus provides a pressure equalization device which is compact and allows high degassing flows.

[0015] In addition, the membrane can be gas permeable and / or liquid impermeable, for example to allow air to pass through the membrane so as to equalize the pressure inside the battery housing with the ambient pressure outside the battery housing. The membrane can be integrated or molded onto the valve element. In addition, all orifices can be covered with a single membrane, or each orifice can be covered with a separate membrane.

[0016] Alternatively, the membrane may be configured to move or deform in a reversible manner, for example to equalize the pressure inside the battery housing with the ambient pressure outside the battery housing.

[0017] The valve element may include a disk. The valve element or disk may include a cover. At least a portion of the orifice may be adjacent to the disk or cover. At least a portion of the orifice may at least partially surround the disk or cover. Alternatively, the orifice may extend through the disk or cover. The disk or cover may be rigid or flexible. The disk or cover may be flat or curved. The disk or cover may be squeezed or pushed into a closed position, for example, in which the disk or cover covers the fluid passage.

[0018] An advantage of the present invention is that the cage may include a central support. The fluid passage may consist of one of two or more fluid passages surrounding the central support. The valve element may include a flexible umbrella-shaped valve element. The valve element may include a rod that may be connected to the central support.

[0019] In addition, the disc can be pushed toward the closed position by a pressure member (such as a spring), for example to cover the fluid passage. The disc or cage may include a seal or sealing member, such as a seal or peripheral sealing member. The seal or sealing member may extend around the periphery of (one or more) fluid passages or the disc. The seal or sealing member may be configured to seal and / or form a seal between the disc and the cage, for example when the disc is in the closed position.

[0020] The disk or cover may be configured to move or deform in a reversible manner at a predetermined pressure differential between the interior and exterior of the battery housing to prevent overpressure from building up inside the battery housing.

[0021] The cover may extend radially from the stem, for example to cover the fluid passage.

[0022] An advantage of the invention is that the orifice is one of two or more holes through the disc or cover. Each of these holes can be covered by a membrane or a corresponding membrane.

[0023] In addition, the cage may include a lip and / or a seal. The gasket may be spaced apart from the lip. The seal and lip may be configured to capture a wall of the battery housing between the seal and the lip during use, for example to seal the cage in an aperture of the battery housing.

[0024] Additionally, the cage may include a bayonet connection. The bayonet connection may have two or more flanges, each of which may define a portion of the lip.

[0025] The cage may include a valve seat. When the disc or cover covers the fluid passage, the valve element or the disc or cover of the valve element may engage the valve seat, for example, seal against the valve seat. The cage may include a sealing component. The seal may include a gasket and / or a valve seat. The seal may be connected to the valve seat, for example, by one or more bridging posts.

[0026] The disc or cover may include one or more sealing lips, which may be configured to engage the valve seat. The (or at least) one sealing lip may include a pair of sealing lips, which may be spaced apart, for example, the at least one sealing lip may include a pair of spaced apart sealing lips.

[0027] The seal and / or valve seat and / or sealing component may be integrally formed with the cage, for example, by a molding process. The seal may be located on a first side (e.g., bottom side) of the cage. The valve seat may be located on a second side (e.g., top side) of the cage, which may be opposite to the first side. The bridging post may extend through the cage.

[0028] The pressure member that pushes the disk toward the closed position can be held between the disk and the cover. The disk and / or the cover may include a connector, for example, for connecting to one end of a spring. The disk may include a protrusion that can be received by one end of the pressure member. The cover may include a housing or a sleeve, for example, in which the other end of the pressure member can be received. The cover housing or a socket may surround at least a portion of the disk protrusion. In addition, the cover may include a protrusion that can be received by one end of the pressure member, and / or the disk may include a housing or a socket, for example, in which the other end of the pressure member can be received, and / or the disk housing or a sleeve may surround at least a portion of the cover protrusion.

[0029] For the avoidance of doubt, all features described herein are also applicable to any aspect of the present invention.

[0030] As part of this application, it is explicitly stated that the various aspects, embodiments, embodiments of the invention, and alternatives (particularly their individual features) disclosed in the preceding paragraphs, claims, and / or the following description and drawings can be used alone or in any combination. In other words, all embodiments and / or features of any embodiment can be combined in any way unless these features are incompatible.

[0031] For the avoidance of doubt, the terms "may", "and / or", "for example", "such as" and any other similar terms used herein must be interpreted as not being limiting, and any feature described herein need not be present. Indeed, any combination of optional features is expressly contemplated without departing from the scope of the invention, whether or not they are explicitly recited in the claims. Applicants reserve the right to amend any originally filed claim or to file any new claim accordingly, including the right to amend any originally filed claim to be dependent upon and / or combined with any feature of any other claim, even if the claim was not originally formulated in that manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Other features and advantages of the present invention will become apparent from the following detailed description which will be understood with reference to the accompanying drawings, in which:

[0033] [ Figure 1 ] Figure 1 A pressure equalization device for a battery housing according to an embodiment of the present invention is illustrated;

[0034] [ Figure 2 ] Figure 2 Shown without cover Figure 1 Devices;

[0035] [ Figure 3 ] Figure 3 Picture shows Figure 1 a side view of the device from below showing the engagement between the cover and the tubular wall;

[0036] [ Figure 4 ] Figure 4 Picture shows Figure 1 A perspective view of the device from below;

[0037] [ Figure 5 ] Figure 5 Picture shows Figures 1 to 4 A cross-sectional view of a device; and

[0038] [ Figure 6 ] Figure 6 A cross-sectional view of a valve element of a pressure equalization device for a battery housing according to another embodiment of the present invention is illustrated;

[0039] [ Figure 7 ] Figure 7 A pressure equalization device for a housing according to another embodiment of the present invention is illustrated;

[0040] [ Figure 8 ] Figure 8 Picture shows Figure 7 A cross-sectional view of the device. DETAILED DESCRIPTION

[0041] Reference below Figure 1 to Figure 1 4 describes different aspects of different embodiments of the present invention in more detail.

[0042] Figures 1 to 5 A pressure equalization device 1 according to a first embodiment of the invention is shown, which is mounted on a battery housing wall 10 (only a portion of which is shown). The device 1 comprises a main axis X, a cage 2, a valve element 3 mounted in the cage 2, and a cover 4 mounted on the cage 2. The battery housing wall 10 comprises an orifice 11, in which the device 1 is mounted.

[0043] The cage 2 comprises a tubular wall 20, a central support 21 connected to the tubular wall 20 by four radial walls 22. Fluid passages 23 are formed between the radial walls 22, which provide fluid passages between the interior of the battery housing wall 10 and the interior of the cage 2.

[0044] Two radial flanges 24 project outwardly from the lower end of the tubular wall 20. The radial flanges 24 cooperate with the two radial tabs 12 of the battery housing wall 10 to provide a bayonet connection to secure the device 1 in the aperture 11 of the battery housing wall 10. A gasket 25 depends from the tubular wall 20, and the radial flanges 24 together form a lip so that the wall of the battery housing 10 is held between the lip and the gasket 25.

[0045] The cage 2 is thus assembled in the orifice 11, which is formed on the top of the battery, with a 1 / 2 turn fixing system. This solution makes it possible to free up as much of the available space of the orifice 11 as possible and thus optimize the flow of fluid through the fluid passage 23 of the cage 2. Thus, this profile in a 1 / 2 turn configuration to be fixed on the battery housing wall 10 makes it possible to obtain an optimal flow to evacuate the pressure inside the battery by freeing up as much of the orifice 11 of the battery housing as possible.

[0046] The cover 4 surrounds the tubular wall 20 of the cage 2 and covers the open end of the tubular wall. The cover 4 includes grooves 40 that receive the protrusions 26 on the tubular wall 20 to provide a connection between the cover 4 and the tubular wall 20. More specifically, the tubular wall 20 includes a seal 27 around its open end, and each of the grooves 40 of the cover 4 includes a helical segment 41. These helical segments 41 cooperate with the protrusions 26 of the tubular wall 20 during rotation to move the seal 27 closer to and further away from the cover 4.

[0047] Accordingly, if Figure 1 As shown, rotation of the cover 4 in the direction indicated by arrow 42 pulls the cover 4 further on the tubular wall 20, thereby forming a tight connection between the cover and the tubular wall. This configuration can be advantageous when pressure testing of the battery housing is required. Specifically, the open position is used for venting / degassing (normal operation), while the closed position is used to perform a 100% air leakage test of the battery housing.

[0048] In this embodiment of the invention, the bayonet fitting includes only two flanges 24, but the bayonet fitting also includes a pair of spring-loaded locking stops 28. The tabs 12 that protrude into the apertures 11 extend over most of the circumference so that the locking stops 28 snap into place between the tabs 12, thereby preventing the cage 2 from rotating when the cover 4 is rotated relative to the cage.

[0049] The valve element 3 includes a rod 31 connected to the central support 21 and a cover 32 extending radially from the rod 31, which covers the fluid passage 23. Therefore, the valve element 3 is an umbrella-shaped valve element 3. The cover 32 preferably has a dome shape and is made of a flexible material in order to increase the closing tension. According to a variation of the present invention, the cover 32 has a flat shape. The umbrella-shaped valve element 3 can be made of a shock-absorbing material having a high-strength polytetrafluoroethylene (PTFE) film.

[0050] The cover 32 includes four holes 33 through its thickness which are covered by a membrane 34. The membrane 34 is gas permeable and liquid impermeable to allow air to pass through the membrane to equalize the pressure inside the battery housing 10 with the ambient pressure outside the battery housing 10.

[0051] Preferably, the membrane 34 is a molded non-flexible umbrella valve element 3. Alternatively, the aperture 33 may be covered by a corresponding membrane 34. In some embodiments of the invention, the membrane 34 may be air impermeable and may be designed with sufficient flexibility to allow some pressure equalization.

[0052] During use, the air inside the battery housing becomes equalized by the transport of air through the membrane 34. If the pressure inside the battery housing exceeds a predetermined threshold, the cover 32 of the umbrella valve element 3 is forced to flex away from the fluid passage 23. Thus, high-pressure air can be exhausted from the battery housing to prevent overpressure.

[0053] Thus, in operation, the present invention enables two pressure equalization functions to be performed. The first function is called the degassing function, in which the cover 32 of the valve element 3 is deformed due to the high pressure from the battery, when the housing is in a thermal runaway situation (emergency situation), and it is necessary to degas the housing in a very short period of time; otherwise, the battery will explode.

[0054] The second function is called ventilation function, in which the membrane 34 acts as a filter, which compensates for changes in air pressure to maintain the pressure inside the battery equal to the pressure outside. The membrane 34 can be a high-tech fabric (PTFE) that is impermeable to liquids but permeable to air. Therefore, the membrane is adapted to allow air to pass through at a reduced flow rate, thereby achieving the ventilation function.

[0055] Thus, the valve element 3 of the valve type makes it possible to compensate for pressure changes inside the battery and to release the pressure systematically (emergency degassing valve). In other words, the valve element 3 can both vent to balance the internal pressure to make it equal to the external pressure, and degas high internal pressures (emergency situations) in a short time, and is waterproof against high water pressure from the outside.

[0056] Reference now Figure 6 , we see a valve element 103 according to a second embodiment of the invention, which is similar to the first embodiment of the invention in that like features are numbered with like numerals increased by 100. The valve element 103 according to this embodiment of the invention differs from the valve element of the first embodiment of the invention in that the cover 132 includes reinforcing ribs 135 surrounding the aperture 133.

[0057] As in Figure 6As more clearly shown in FIG. 1 , the rod 131 includes a tapered end 131a and a tapered portion 131b. The valve member 103 is mounted on the cage 2 by inserting the tapered end 131a of the rod 131 into the central support 21 and forcing the rod 131 into the central support 21 until the tapered end 131a protrudes from the other end and the central support 21 is retained in the narrowed portion 131b. Other arrangements are also possible.

[0058] Reference now Figure 7 and Figure 8 , shows a pressure equalizing device 201 according to another embodiment of the present invention, which is similar to the first embodiment of the present invention in that like features are labeled with like numerals increased by 200. The pressure equalizing device 201 according to this embodiment of the present invention differs from the first embodiment of the present invention in that the valve element 3 is omitted and simply replaced by a membrane 234.

[0059] Therefore, in this embodiment of the invention, only one pressure equalization function is performed, namely the ventilation function. More specifically, the membrane 234 acts as a filter that compensates for changes in air pressure to maintain the pressure inside the battery equal to the pressure outside. As in the previous embodiment of the invention, the membrane 234 is preferably an engineered fabric (PTFE) that is impermeable to liquid but permeable to air, but in other embodiments of the invention, the membrane may simply be deformable to equalize slight changes in pressure. However, unlike the previous embodiment of the invention, the equalization device 201 according to this embodiment of the invention does not include a degassing function.

[0060] In addition, the slot 240 includes projections 243, 244 at each end of the spiral section 241. Thus, when the cover 204 is rotated to the closed position and the open position, the projections 226 on the tubular wall 220 engage. The projections 243, 244 of the slot 240 inhibit but do not prevent the cover 204 from rotating away from the closed position and the open position.

[0061] However, the projection 243 that retains the cover 204 in the open position exceeds the projection 244 that retains the cover 204 in the closed position. Therefore, the torque required to rotate the cover 204 away from the open position is greater than that required to rotate away from the closed position.

[0062] As in the previous case, in the closed position the cover seals against a seal 227 around the open end of the tubular wall 220. This prevents any venting, for example during pressure testing.

[0063] Reference now Fig. 9 and Fig.10, shows a pressure equalizing device 301 according to another embodiment of the present invention, which is similar to the first embodiment of the present invention in that like features are labeled with like numerals increased by 300. The pressure equalizing device 301 according to this embodiment of the present invention differs from the pressure equalizing device of the first embodiment of the present invention in that the umbrella valve element 3 is replaced by a disk 303, and rotation of the cover 304 selectively aligns the windows 340, 329 through the cover 304 with the tubular wall 320.

[0064] The disk 303 has holes 333 in its thickness, which are covered by a molded film 334, and a tubular wall 331 protrudes from the center of the disk 303. The cover 304 also includes an additional tubular wall 343, which is aligned with and surrounds the tubular wall 331 of the disk 303. The device 301 includes a spring 305, a first end of which surrounds the tubular wall 331 of the disk 303 and a second end of which is received in the tubular wall 343 of the cover 304. The spring 305 pushes the disk 303 to a closed position, in which the disk covers the fluid passage 323.

[0065] In this embodiment of the invention, the seal body 306 is molded onto the area of ​​the cage 302. Specifically, the seal body 306 includes a gasket 325 depending from the tubular wall 320 and a disc seal 360 surrounding the fluid passage 323, which engages the disc 303 when in the closed position. The seal body 306 also includes a window gasket 361 surrounding a window 329 through the cage 302.

[0066] Thus, when the cover 304 is in the open position (as shown in FIG. 16 ), fluid can exit the battery housing through the fluid passage 323, through the membrane 334 (or between the cage 302 and the tray 303 when moving), and through the windows 329, 340. However, when the cover 304 is rotated so that the windows 329, 340 are no longer aligned, the window seal 361 seals the fluid passage during a 100% air leak test of the battery housing.

[0067] Reference now Fig.11 and Fig.12 , shows a pressure equalizing device 401 according to another embodiment of the invention, which is similar to the previous embodiment of the invention in that like features are numbered with like numerals increased by 100. The pressure equalizing device 401 according to this embodiment of the invention differs from the previous embodiment of the invention in that a hole 433 passes through the base of the cage 402, the diameter of the disc 403 corresponds to the diameter of the tubular wall 433, and the disc 403 has a peripheral seal 436 that seals into the base of the cage 402. Thus, in the event of an overpressure condition, the disc 403 is moved to reveal a central aperture 423a through the base of the cage 402.

[0068] A person skilled in the art will appreciate that several variations of the embodiments described above are conceivable without departing from the scope of the present invention.

[0069] Throughout the description section and claims of this specification, the words "comprise" and "include" and their variations mean "including but not limited to", and are not intended to (and do not) exclude other parts, additives, components, integral bodies or steps. Throughout the description section and claims of this specification, the singular includes the plural unless the context requires otherwise. In particular, when the indefinite article is used, this specification should be understood to include the plural as well as the singular unless the context requires otherwise.

[0070] Any feature, entity, characteristic, compound, or grouping described in conjunction with a particular aspect, embodiment, or embodiment of the invention should be understood to be applicable to any other aspect, embodiment, or embodiment of the invention described herein, unless inconsistent therewith. All features disclosed in this specification (including claims, abstract, and drawings) and / or all steps of the method or process so disclosed may be combined in any combination, except for at least some mutually exclusive combinations of such features and / or steps. The invention is not limited to the details of all the foregoing embodiments. The invention extends to any new feature or any new combination of these features disclosed in this specification (including claims, abstract, and drawings), or to any new feature or any new combination of these steps of any method or process so disclosed.

[0071] The reader's attention is drawn to all papers and documents filed concurrently with or prior to this specification in connection with this application, which are open to public inspection with this specification, and the contents of all these papers and documents are incorporated herein by reference.

Claims

1. A pressure equalization device for a battery housing, the device comprising: a cage defining a fluid passage; A cover, the cover being mounted on the cage frame; as well as and a membrane covering the fluid passage to equalize the pressure inside the housing with the ambient pressure outside the housing; Wherein the cover is movable, in use, between an open configuration in which air can escape and a closed configuration in which the housing is sealed.

2. The pressure equalization device according to claim 1, wherein: The membrane is gas permeable and liquid impermeable to allow air to pass through the membrane to equalize the pressure inside the battery housing with the ambient pressure outside the battery housing.

3. The pressure equalization device according to claim 1 or claim 2, wherein: The lid is rotatable between the open configuration and the closed configuration.

4. The pressure equalization device according to claim 3, wherein: At least one of the cover and the cage includes an angled, spiral or helical configuration.

5. The pressure equalization device according to claim 4, wherein: The formation cooperates with formation on the other of the cover and the cage to translate the cover relative to the cage when the cover is rotated between the open configuration and the closed configuration.

6. A pressure equalization device according to any preceding claim, wherein: The cover is twistable between the open configuration and the closed configuration.

7. A pressure equalization device according to any preceding claim, wherein: The device includes a sealing member on one or both of the cover and / or the cage that seals the housing when the cover is in the closed configuration.

8. A pressure equalization device according to any preceding claim, wherein: The cover and the cage each include a window; when the cover is in the open position, the window in the cover is aligned with the window in the cage, and when the cover is in the closed position, the window in the cover is not aligned or offset with the window in the cage.

9. The pressure equalization device according to claim 8, wherein: The device includes a gasket configured to seal fluid communication between the windows when the cover is in the closed position.

10. A pressure equalization device according to any preceding claim, wherein: The device comprises: a valve element covering the fluid passage; the valve element including an orifice through its thickness, and the membrane being attached to the valve element and covering the orifice, wherein the membrane is configured to equalize the pressure inside the battery housing with the ambient pressure outside the battery housing in use, At the same time, the valve element is configured to move or deform in a reversible manner under a predetermined pressure difference between the interior and the exterior of the battery housing to prevent overpressure inside the battery housing.

11. The pressure equalization device according to claim 10, wherein: The cage includes a central support, and the fluid passage is one of two or more fluid passages surrounding the central support, wherein the valve element includes a rod connected to the central support and a cover radially extending from the rod to cover the fluid passage.

12. The pressure equalization device according to claim 11, wherein: The aperture is one of two or more holes through the cover, one of the two or more holes being covered by the membrane or a corresponding membrane.

13. A pressure equalization device according to any preceding claim, wherein: The cage includes a lip and a gasket spaced from the lip, the lip and the gasket being configured to capture a wall of the battery housing between the lip and the gasket in use to seal the cage in an aperture in the battery housing.

14. A pressure equalization device according to claim 13 when dependent on claim 11 or claim 12, wherein: The seal is connected to the valve seat by bridging posts extending through the cage.

15. A pressure equalization device according to claim 13 or claim 14, wherein: The cage includes a bayonet connection having two or more flanges, each of the flanges defining a portion of a lip of the cage.

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