Underrun protection plate and motor vehicle with underrun protection plate

Abstract

The invention relates to an underrun protection plate (5) with a multi-layer base body (9), wherein the base body (9) has at least a first outer plate (10), a second outer plate (11) and optionally at least one intermediate plate which is arranged between the outer plates (10, 11), wherein at least one flow channel (12) is provided in the base body (9), wherein the base body (9) has at least one inlet opening (13) which is fluidically connected to the at least one flow channel (12), and the base body (9) has at least one outlet opening (14) which is fluidically connected to the at least one flow channel (12), wherein the at least one outlet opening (14) is provided with a check valve (15) so that gases can be discharged from the flow channel (12) via the check valve (15), wherein the check valve (15) prevents gases from being admitted into the flow channel (12).The invention also relates to a motor vehicle (1) with an underrun protection plate (5).

Description

[0001] The invention relates to an underrun protection plate, in particular for a motor vehicle and a motor vehicle with an underrun protection plate.

[0002] Motor vehicles with underbody protection plates are known in the art. Such underbody protection plates are typically single-layer, sturdy plates located on the underbody and protecting the vehicle's body from impacts from below, for example, when striking an object.

[0003] Also known in the prior art are electrically powered motor vehicles that have a battery arranged in the underbody with a battery housing and battery cells arranged therein. Such batteries, particularly those with lithium-ion cells, have the disadvantage that the battery cells can react thermally if damaged, generating hot gases that can ignite when exposed to atmospheric oxygen when escaping from the battery cell or battery, resulting in flames. This can lead to a thermal event that can even endanger the entire vehicle.

[0004] DE 20 2021 107 025 U1 discloses a battery with a battery housing, wherein the side wall of the battery housing is formed with a flow channel for escaping gases, wherein a fire extinguishing chamber is arranged downstream of the outlet opening of the flow channel thus formed.

[0005] DE 20 2021 107 010 U1 discloses a battery with a battery housing, wherein the side wall of the battery housing is formed with a flow channel for escaping gases, wherein various different outlet openings are provided, wherein a fire extinguishing chamber is arranged downstream of the first outlet openings and an explosion-proof valve is integrated into the second outlet openings.

[0006] Such a battery with such a complex battery housing is overall complicated to manufacture and also expensive, which should be avoided.

[0007] The objective is to create an underbody protection plate that effectively protects a motor vehicle with an integrated battery, preventing flames from forming in the event of a thermal event involving the battery. The objective is also to create a motor vehicle with an improved underbody protection plate that helps prevent flames from forming in the event of a thermal event involving the battery.

[0008] The problem of the underrun protection plate is solved with the features of claim 1.

[0009] An embodiment of the invention relates to an underrun protection plate with a multi-layer base body, wherein the base body has at least a first outer plate, a second outer plate and optionally at least one intermediate plate which is arranged between the outer plates, wherein at least one flow channel is provided in the base body, wherein the base body has at least one inlet opening which is fluidically connected to the at least one flow channel and the base body has at least one outlet opening which is fluidically connected to the at least one flow channel, wherein the at least one outlet opening is provided with a check valve so that gases can be discharged from the flow channel via the check valve, wherein the check valve prevents gases from being admitted into the flow channel.This allows the hot, flammable gas from the battery cell to escape to the outside air only after it has already cooled down by flowing through the underrun protection plate. The check valve prevents atmospheric oxygen from entering the underrun protection plate's flow channel uncontrollably, preventing the still-hot gases from igniting in the underrun protection plate. Once the gases have cooled down at the outlet from the underrun protection plate, the risk of ignition is significantly reduced due to mixing with atmospheric oxygen, thus preventing flame formation.

[0010] In one embodiment, it is advantageous if a plurality of outlet openings are provided, in particular at least two outlet openings, each outlet opening being provided with a check valve. This ensures that the pressure conditions and the outflow velocities are within the desired range, thus also suppressing flame formation.

[0011] It is also advantageous if the at least one outlet opening or the plurality of outlet openings are arranged in the first outer plate and / or in the second outer plate. This allows the discharge of the escaping gas to be directed in the desired direction.

[0012] In a further embodiment, it is advantageous if the at least one inlet opening or the plurality of inlet openings are arranged in the first outer plate or in the second outer plate. Preferably, the inlet openings in the outer plate are directly opposite the battery to achieve uncomplicated, direct overflow from the battery to the underrun protection plate.

[0013] In an alternative embodiment, it is also expedient for the at least one intermediate plate to have channel-shaped depressions or recesses that form the at least one flow channel. This allows the at least one flow channel to be designed expediently. Alternatively, the at least one flow channel could also be designed by means of embossing or similar features on at least one of the outer plates.

[0014] The problem of the motor vehicle is solved with the features of claim 6.

[0015] An embodiment of the invention relates to a motor vehicle with a body and with a battery, wherein the battery is arranged in or on the underbody of the body, wherein an underrun protection plate is arranged below the battery.

[0016] In one embodiment, it is advantageous if the battery has a battery housing and battery cells arranged in the battery housing, wherein the battery housing has at least one venting opening or venting openings.

[0017] In one embodiment, it is advantageous if the battery has at least one battery module or a plurality of battery modules, wherein the at least one battery module or each of the battery modules has a plurality of battery cells, wherein the battery module has a module housing or the battery modules have module housings, wherein the module housing or the module housings each have at least one venting opening or a plurality of venting openings.

[0018] In one embodiment, it is advantageous if the battery module or the battery modules are arranged in the battery housing.

[0019] In one embodiment, it is advantageous if the battery and the underrun protection plate are arranged relative to one another such that the at least one venting opening is aligned with the at least one inlet opening of the underrun protection plate or the battery and the underrun protection plate are arranged relative to one another such that the venting openings are aligned with the inlet openings of the underrun protection plate.

[0020] The invention will be explained in detail below using an exemplary embodiment with reference to the drawings. In the drawings: Fig. 1 a schematic view of an embodiment of a motor vehicle with a battery and an underrun protection plate, Fig. 2 a schematic partially sectioned view of an embodiment of a battery with an underrun protection plate, and Fig. 3 a schematic perspective view of an embodiment of an underrun protection plate.

[0021] The Fig. Figure 1 shows a schematic representation of a motor vehicle 1 with a body 2 and a battery 3. The motor vehicle 1 is, for example, an electrically powered motor vehicle 1 or a motor vehicle 1 with an electric drive and an alternative drive. The battery 3 supplies the electric drive.

[0022] The battery 3 is arranged in or on the underbody 4 of the body 2, so that it takes up little space in the vehicle interior.

[0023] An underrun protection plate 5 is arranged beneath the battery 3 to protect the battery 3 and the underbody 4. This allows the underrun protection plate 5 to absorb impacts from below before the battery 3 is damaged.

[0024] According to the inventive concept, the underrun protection plate 5 has a flow channel. This flow channel serves to convey the hot gases from the battery 3, which flow from the battery 3 to the underrun protection plate 5.

[0025] The battery 3 is designed, for example, such that it has a battery housing 6 and battery cells 7 arranged in the battery housing 6. The battery cells 7 can be arranged in at least one stack.

[0026] If the battery cells 7 are, for example, Li-ion battery cells, it can happen that if a battery cell 7 is damaged, a thermal event occurs in the battery cell 7, resulting in hot gases escaping from the battery cell 7. To allow the hot gases to escape from the battery housing 6, the battery housing 6 has at least one flow channel, which, if necessary, cools the hot gases at least slightly and releases them from the battery housing 6 in a defined manner. For this purpose, the battery housing 6 also has at least one venting opening 8 or venting openings 8. The battery housing 6 can be designed as an extruded profile with one or more chambers for the arrangement of the battery cells 7. For example, each chamber can accommodate at least one stack of battery cells 7. Each stack comprises, for example and preferably, between two and eight battery cells 7.

[0027] In one embodiment, the battery 3 may also comprise at least one battery module or a plurality of battery modules, wherein the at least one battery module or each of the battery modules comprises a plurality of battery cells 7. The respective battery module comprises a module housing, or the battery modules comprise module housings. The module housing may also be designed as an extruded profile with one or more chambers for arranging the battery cells 7. Thus, for example, at least one stack of battery cells 7 can be accommodated in each chamber. Each stack comprises, for example and preferably, between two and eight battery cells 7.

[0028] The module housing can serve as a battery housing 6, or several module housings can form a battery housing 6. The battery module or battery modules can also be arranged in the battery housing 6.

[0029] Accordingly, the module housing or the module housings can each have at least one degassing opening 8 or several degassing openings 8.

[0030] According to Fig. 1 shows that the battery 3 and the underrun protection plate 5 are arranged relative to one another such that at least one vent opening 8 of the battery 3 or of the battery housing 6 or of the module housing is aligned with at least one inlet opening of the underrun protection plate 5, or the battery 3 and the underrun protection plate 5 are arranged relative to one another such that the vent openings 8 of the battery 3 are aligned with inlet openings of the underrun protection plate 5. Gas can thus flow from the battery 3 to the underrun protection plate 5, flow through the underrun protection plate 5, cool therein, and exit the underrun protection plate 5 again in a cooled state.

[0031] The Fig. 2 shows a battery 3 with an underrun protection plate 5 in a schematic partial view. Fig. 3 shows the underrun protection plate 5 in a perspective view.

[0032] The underrun protection plate 5 has a multi-layered base body 9. The base body 9 has at least a first outer plate 10 and a second outer plate 11, wherein at least one intermediate plate can optionally be provided, which can be arranged between the two outer plates 10, 11. The at least one optional intermediate plate can be designed such that it has channel-shaped depressions or recesses that form the at least one flow channel 12.

[0033] Alternatively, the first outer plate 10 and / or the second outer plate 11 can be provided with an embossing 16 or the like in order to form the flow channel 12 or the flow channels 12.

[0034] In Fig.In Figure 2, the first outer plate 10 is largely hidden, and essentially only the second outer plate 11 is visible. It can be seen that embossings 16 are provided in the second outer plate 11.

[0035] The underrun protection plate 5 is designed such that at least one flow channel 12 is provided in the base body 9, preferably several flow channels 12.

[0036] To allow the gas to flow into the base body 9 and into the flow channel 12 of the base body 9, the base body 9 has at least one inlet opening 13, which is fluidly connected to the at least one flow channel 12. To allow the gas to exit the base body 9 again after flowing through the flow channel 12, the base body 9 has at least one outlet opening 14, which is fluidly connected to the at least one flow channel 12.

[0037] The at least one outlet opening 14 is provided with at least one check valve 15 so that gases can be discharged from the flow channel 12 via the check valve 15, but the check valve 15 prevents gases from being admitted into the flow channel 12 in the opposite direction.

[0038] Preferably, the at least one check valve 15 is designed as a flap that closes an outlet opening 14 under spring load. When there is excess pressure inside, the flap opens, and when there is excess pressure outside, the flap remains closed. By selecting the spring force of the return spring, the prevailing internal pressure at which the flap opens can be determined. Accordingly, if there are multiple check valves 15, multiple flaps can be provided.

[0039] Advantageously, a plurality of outlet openings 14 are provided, in particular at least two outlet openings 14. Each outlet opening 14 is provided with a check valve 15.

[0040] Depending on the desired outlet direction, the at least one outlet opening 14 or the plurality of outlet openings 14 can be arranged in the first outer plate 10 and / or in the second outer plate 11. Preferably, the at least one outlet opening 14 is arranged on the underside of the underrun protection plate 5.

[0041] It is also advantageous if the at least one inlet opening 13 or the plurality of inlet openings 13 are arranged in the first outer plate 10 or in the second outer plate 11, depending on how the underrun protection plate 5 is arranged under the battery 3 and how the transition of the flow channels 12 from the battery 3 to the underrun protection plate 5 is to take place. Preferably, the at least one inlet opening 13 is arranged on the upper side of the underrun protection plate 5. List of reference symbols 1 motor vehicle 2 Body 3 Battery 4 Underbody 5 Underrun protection plate 6 Battery housing 7 battery cells 8 Degassing opening 9 Basic body 10 first outer plate 11 second outer plate 12 flow channel 13 Inlet opening 14 Outlet opening 15 Check valve 16 Embossing QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 20 2021 107 025 U1

[0004] DE 20 2021 107 010 U1

[0005]

Claims

[1] Underrun protection plate (5) with a multi-layer base body (9), wherein the base body (9) has at least a first outer plate (10), a second outer plate (11) and optionally at least one intermediate plate which is arranged between the outer plates (10, 11), wherein at least one flow channel (12) is provided in the base body (9), wherein the base body (9) has at least one inlet opening (13) which is fluidically connected to the at least one flow channel (12) and the base body (9) has at least one outlet opening (14) which is fluidically connected to the at least one flow channel (12), wherein the at least one outlet opening (14) is provided with a check valve (15) so that gases can be discharged from the flow channel (12) via the check valve (15), wherein the check valve (15) prevents gases from being admitted into the flow channel (12). [2] Underrun protection plate (5) according to claim 1, characterized bythat a plurality of outlet openings (14) are provided, in particular at least two outlet openings (14) are provided, wherein each outlet opening (14) is provided with a check valve (15). [3] Underrun protection plate (5) according to claim 1 or 2, characterized by that the at least one outlet opening (14) or the plurality of outlet openings (14) are arranged in the first outer plate (10) and / or in the second outer plate (11). [4] Underrun protection plate (5) according to claim 1, 2 or 3, characterized by that the at least one inlet opening (13) or the plurality of inlet openings (13) are arranged in the first outer plate (10) or in the second outer plate (11). [5] Underrun protection plate (5) according to one of the preceding claims, characterized by that the at least one intermediate plate has channel-shaped depressions or recesses which form the at least one flow channel (12). [6] Motor vehicle (1) with a body (2) and with a battery (3), wherein the battery (3) is arranged in or on the underbody (4) of the body (2), wherein an underrun protection plate (5) is arranged below the battery (3), wherein the underrun protection plate (5) is designed according to at least one of the preceding claims. [7] Motor vehicle (1) according to claim 6, characterized by that the battery (3) has a battery housing (6) and battery cells (7) arranged in the battery housing (6), wherein the battery housing (6) has at least one venting opening (8) or venting openings (8). [8] Motor vehicle (1) according to claim 6 or 7, characterized bythat the battery (3) has at least one battery module or a plurality of battery modules, wherein the at least one battery module or each of the battery modules has a plurality of battery cells (7), wherein the battery module has a module housing or the battery modules have module housings, wherein the module housing or the module housings each have at least one venting opening (8) or a plurality of venting openings (8). [9] Motor vehicle (1) according to one of the preceding claims 7 or 8, characterized by that the battery module or the battery modules are arranged in the battery housing (6). [10] Motor vehicle (1) according to one of claims 7, 8 or 9, characterized bythat the battery (3) and the underrun protection plate (5) are arranged relative to one another such that the at least one venting opening (8) is aligned with the at least one inlet opening (13) of the underrun protection plate (5) or the battery (3) and the underrun protection plate (5) are arranged relative to one another such that the venting openings (8) are aligned with the inlet openings (13) of the underrun protection plate (5).

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