Storage housing for an electrical energy storage device with a valve for liquid drainage

Abstract

Storage housing (1) for an electrical energy storage device of a motor vehicle, comprising - several housing walls (3a, 3b, 3c, 3d) enclosing a receiving space (2) for receiving at least one storage component of the electrical energy storage device, wherein at least one of the housing walls (3d) has a through-opening (10a) for releasing a liquid (5) accumulated in the receiving space (2) into an environment (8) of the storage housing (1), and - at least one valve device (9a) designed to discharge the liquid (5) from the receiving chamber (2) into the environment (8) via the through-opening (10a) and to at least reduce the ingress of liquid (15) from the environment (8) into the receiving chamber (2) via the through-opening (10a), characterized in that the at least one valve device (9a) has a passive valve with rigid structures (14) arranged in or on the through-opening (10a), which has a first flow resistance in a first flow direction (R1) from the receiving chamber (2) into the environment (2) and has a second flow resistance that is greater than the first flow resistance in a second flow direction (R2) from the environment (8) into the receiving chamber (2).

Description

[0001] The invention relates to a storage housing for an electrical energy storage device of a motor vehicle. The storage housing has a plurality of housing walls which enclose a receiving space for receiving at least one storage component of the electrical energy storage device. At least one of the housing walls has a through-opening for discharging a liquid collected in the receiving space into an environment of the storage housing. Furthermore, the storage housing has at least one valve device which is designed to drain the liquid from the receiving space into the environment via the through-opening and to at least reduce the penetration of liquid from the environment into the receiving space via the through-opening. The invention also relates to an electrical energy storage device.

[0002] In this case, the focus is on electrical energy storage devices, which are used in particular as traction batteries for electrically powered motor vehicles, i.e., hybrid or electric vehicles. Such electrical energy storage devices typically comprise a plurality of storage components, including a plurality of interconnected storage cells, which are arranged in a receiving space of a storage housing of the electrical energy storage device. The storage housing is generally technically sealed but has a pressure equalization element for pressure equalization with the environment of the motor vehicle. Furthermore, the energy storage device can comprise a coolant-carrying cooling device for cooling the storage cells.

[0003] Particularly in regions with hot and humid outdoor climates, it can happen that the internal climate within the storage housing adapts to the external climate as air from the environment flows through the pressure equalization element into the storage housing's receiving space. If the temperature of the cooling device falls below the dew point of the incoming air, water from the air condenses on the cooling device and collects in the receiving space. In the event of a radiator rupture, escaping coolant can also lead to a buildup of liquid in the receiving space. Such buildup of liquid is undesirable because it can damage the storage components of the electrical energy storage system. Such damage can lead to a thermal event in a storage component. In addition, flammable hydrogen can form in the receiving space.

[0004] Therefore, it is known from the prior art, for example, from DE 10 2013 014 903 A1, to drain the fluid from the receiving chamber, for example, via a valve. Such valves usually have a movable valve body, which opens a through-opening in a housing wall of the storage housing for draining the fluid from the receiving chamber into the environment and prevents fluid from the environment from penetrating the receiving chamber. Due to the movable valve body, such a valve is susceptible to damage, for example, due to driving-related vibrations.

[0005] DE 10 2020 202 752 A1 discloses an electrical energy storage device. The electrical energy storage device comprises at least a first electrical energy storage module having a first housing and a second electrical energy storage module having a second housing, wherein the electrical energy storage modules can be temperature-controlled by means of a temperature-control medium flow. A connecting element is arranged between the first housing and the second housing, by means of which the temperature-control medium flow can be conducted from the first housing into the second housing. The connecting element has at least one valve and at least one sensor.

[0006] DE 11 2019 005 681 T5 discloses a drainage system that allows fluid to be drained from a battery pack while maintaining the structural integrity of the battery pack. A frame of the battery pack comprises several retaining elements in which valves are arranged to allow fluid to escape from the battery pack. The valves are arranged such that forces normally acting when a vehicle is moving, such as acceleration, deceleration, and rotational forces, cause the fluid to flow to and through the valves.

[0007] It is an object of the present invention to provide a particularly robust solution by means of which a liquid can be drained from a storage housing of an electrical energy storage device.

[0008] This object is achieved according to the invention by a storage housing and an electrical energy storage device having the features according to the respective independent patent claims. Advantageous embodiments of the invention are the subject of the dependent patent claims, the description, and the figures.

[0009] A storage housing according to the invention for an electrical energy storage device of a motor vehicle comprises a plurality of housing walls enclosing a receiving space for receiving at least one storage component of the electrical energy storage device, wherein at least one of the housing walls has a through-opening for discharging a liquid collected in the receiving space into an environment of the storage housing. Furthermore, the storage housing comprises at least one valve device designed to drain the liquid from the receiving space into the environment via the through-opening and to at least reduce the penetration of liquid from the environment into the receiving space via the through-opening.The at least one valve device has a passive valve with rigid structures arranged in or on the through-opening, which has a first flow resistance in a first flow direction from the receiving space into the environment and has a second flow resistance that is greater than the first flow resistance in a second flow direction from the environment into the receiving space.

[0010] The invention also includes an electrical energy storage device having at least one storage component and a storage housing according to the invention, wherein the at least one storage component is arranged in the receiving space of the storage housing. In particular, the electrical energy storage device has a plurality of storage components, for example storage cells. The storage cells can be, for example, round cells, prismatic battery cells and / or pouch cells. Further storage components, for example electronic components such as sensor devices, cooling devices, etc., can also be arranged in the receiving space. The storage housing has a plurality of housing walls which enclose the receiving space for the storage components. The through-opening or feedthrough, via which liquid can be discharged from the receiving space to the outside into the environment, is arranged in at least one housing wall.This liquid can collect in the receiving chamber, for example, due to condensation and / or a radiator breakage.

[0011] In order to prevent large quantities of liquid from entering the receiving space via the through-opening from the environment, for example due to splash water or a static water column, at least one valve device is provided. This drains the liquid from the receiving space and reduces, but preferably blocks, the penetration of liquid into the receiving space. In other words, the valve device is designed to permit a flow of liquid in the first flow direction from the receiving space into the environment and to impede, in particular completely block, the flow in the opposite second flow direction from the environment into the receiving space. For this purpose, the valve device has the passive valve. Preferably, the passive valve is a Tesla valve. The passive valve can, for example, be arranged directly in the through-opening of the housing wall.The passive valve can also be arranged outside the receiving space or inside the receiving space on the housing wall of the storage housing and be fluidically coupled to the through-opening. This passive valve exhibits a higher flow resistance in the second flow direction than in the first flow direction. The special feature of the passive valve is that it has no movable valve body and thus no moving mechanical parts. Instead, it can provide the different flow resistances and thus the valve function solely through the geometric design of its rigid structures. The rigid structures form flow channels for the fluid.

[0012] In the case of the Tesla valve, for example, this comprises a rigid channel system with a main flow channel and loop-shaped, flow-reversing secondary flow channels branching off from the main flow channel. The Tesla valve is designed to guide the fluid in the first flow direction, in particular exclusively, via the main flow channel and to guide it at least partially via the flow-reversing secondary flow channels in the second flow direction. The loop-shaped secondary flow channels are thus shaped and connected to the main flow channel in such a way that the fluid can only enter the secondary flow channels when flowing from the main flow channel in the second flow direction, and counteracts the flow in the main flow channel when exiting the secondary flow channels.This means that the liquid entering the secondary flow channels either flows back into the first flow direction and thus into the environment when exiting, or stops the liquid flowing via the main flow channel along the second flow direction by building up a counterpressure and thus at least reduces penetration into the receiving space.

[0013] The use of such a passive valve provides a particularly robust and simple valve device.

[0014] It can also be provided that the at least one valve device additionally has a check valve arranged between the receiving space and the passive valve. The check valve is designed in particular as a flow pressure-controlled, spring-loaded check valve. The check valve clears the path for the fluid from the receiving space to the passive valve as soon as a (flow) pressure of the fluid exceeds a predetermined threshold. In addition, the check valve prevents fluid from the environment, which has overcome the second flow resistance of the passive valve and was guided through the passive valve in the second flow direction, from penetrating the receiving space. By using the upstream passive valve, the spring return force can be designed to be low.This means that even low static or dynamic pressures, for example when the water level in the receiving space is low, can lead to opening.

[0015] In a further development of the invention, the valve device comprises at least one valve housing, in which the non-return valve and the passive valve are arranged, and which is arranged in the receiving space of the storage housing at the through-opening. The valve housing thus forms a drainage channel arranged in the receiving space, through which the fluid exits from the receiving space into the environment. Fluid entering from the environment via the passive valve is held in the valve housing by the non-return valve and can be returned to the environment via the passive valve.

[0016] In one embodiment of the invention, the storage housing comprises a first through-opening and a first valve device, which are arranged in a first housing wall and are designed to discharge fluid from the receiving space in a first flow direction dependent on the vehicle's acceleration, and at least one second through-opening and at least one second valve device, which are arranged in a second housing wall and are designed to discharge fluid from the receiving space in a second flow direction dependent on the vehicle's acceleration. This embodiment is based on the finding that a flow direction of the fluid in the receiving space depends on a sign of the acceleration of the motor vehicle. When the motor vehicle accelerates, the fluid flows in the first flow direction, and when the motor vehicle brakes, the fluid flows in the opposite second flow direction.In order to prevent the liquid from sloshing around uncontrollably in the receiving space, at least two through-openings and at least two valve devices, each with a passive valve, for example a Tesla valve, are provided in two opposite housing walls, which can discharge the liquid from the receiving space into the environment, depending on the flow direction.

[0017] It proves advantageous if at least one of the housing walls has at least one fluid reservoir for collecting the fluid, from which the fluid emerges due to vehicle acceleration and flows to one of the valve devices. In particular, the fluid reservoir is arranged in a bottom housing wall, and the through-openings and the valve devices are arranged in a front and rear housing wall. The fluid reservoir can, for example, be a recess in the housing base. Additionally, guide grooves sloping toward the recess can be formed in the housing base to guide the fluid into the reservoir.From a certain amount of fluid in the reservoir and / or from a certain, positive or negative, acceleration of the motor vehicle, the fluid can escape from the reservoir, flow towards one of the valve devices and activate the valve device with sufficient pressure to discharge the fluid.

[0018] In a further embodiment of the invention, the storage housing additionally has an air inlet and an air outlet for conducting air through the receiving space, as well as a fan for generating an air flow from the air inlet to the air outlet, which is designed to absorb moisture from the receiving space and transport it to the environment via the air outlet in order to reduce the liquid in the receiving space. The air inlet and the air outlet can be provided, for example, for pressure equalization in the storage housing and can be equipped, for example, with a membrane. The fan, which can be arranged, for example, at the air inlet, sucks in the air in the region of the air inlet and conveys it towards the opposite air outlet. The resulting continuous air flow absorbs liquid and transports it from the environment via the air outlet.

[0019] The embodiments presented with reference to the storage housing according to the invention and their advantages apply accordingly to the electrical energy storage device according to the invention.

[0020] Further features of the invention emerge from the claims, the figures, and the description of the figures. The features and combinations of features mentioned above in the description, as well as the features and combinations of features mentioned below in the description of the figures and / or shown alone in the figures, can be used not only in the respective specified combination, but also in other combinations or on their own.

[0021] The invention will now be explained in more detail using a preferred embodiment and with reference to the drawings.

[0022] They show: Fig. 1 is a schematic representation of an embodiment of a storage housing; Fig. 2 the storage enclosure according to Fig. 1 when draining fluid; Fig. 3 a schematic representation of another embodiment of a storage housing; Fig. 4 a schematic representation of an embodiment of a valve device of the storage housing, Fig. 5 the valve device according to Fig. 4 when draining liquid from the storage housing; Fig. 6 the valve device according to Fig. 4 when blocking dynamic fluid from an environment of the storage housing; and Fig. 7 the valve device according to Fig. 4 when blocking static fluid from an environment of the storage enclosure.

[0023] In the figures, identical and functionally identical elements are provided with the same reference numerals.

[0024] Fig. 1 shows a storage housing 1 for an electrical energy storage device of a motor vehicle. Storage components, such as storage cells, electronic devices 4, such as control devices and sensor devices, cooling devices for cooling the storage cells, etc., can be arranged in a receiving space 2 of the storage housing 1, which is enclosed by housing walls 3a, 3b, 3c, 3d. The housing walls 3a, 3b, 3c, 3d here are a housing base 3a, a housing front wall 3b, a housing cover 3c, and a housing rear wall 3d. The housing walls 3a, 3b, 3c, 3d can also be formed as subregions of a storage housing 1, which consists of two assembled, trough-shaped housing parts. In the event of a radiator breakage or condensation, liquid 5 may collect in the receiving space 2.Here, the housing base 3a has at least one reservoir 6 in the form of a depression 7, in which the liquid 5 is collected at a defined location in the receiving space 2. Guide grooves can also be arranged in the housing base 3a, which lead to the at least one reservoir 6 and which guide the liquid 5 into the reservoir 6.

[0025] In order to be able to direct the liquid 5 from the receiving space 2 into an environment 8 of the storage housing 2, the storage housing 1 has at least one, here two, valve devices 9a, 9b, which are arranged in or on through-openings 10a, 10b of the housing walls 3b, 3d. Here, a first valve device 9a is integrated into the housing rear wall 3d and discharges the liquid 5, which, as shown in Fig. 2, sloshes from the reservoir 6 to the housing rear wall 3d when the motor vehicle accelerates. A second valve device 9b is integrated into the housing front wall 3b and drains the fluid 5, which sloshes from the reservoir 6 to the housing front wall 3b when the motor vehicle brakes.

[0026] In addition, the storage enclosure 1, as shown in Fig. 3, an air inlet 11a, here in the housing rear wall 3d, and an air outlet 11b, here in the housing front wall 3b, through which an air exchange can take place between the receiving space 2 and the environment 8 for pressure equalization. A blower 12 or fan is arranged at the air inlet 11a, which generates a continuous air flow 13 from the air inlet 11a to the air outlet 11b. This air flow 13 can also transport liquid 5 from the receiving space 2 into the environment 8.

[0027] Fig. 4 shows the valve device 9a, whereby the valve device 9b can be designed in the same way. The valve device 9a has a passive valve 14, which is designed here as a Tesla valve and which is designed to direct the liquid 5 along a first flow direction R1, as in Fig. 5, from the receiving space 2 via the through-opening 10a into the environment 8. In addition, the Tesla valve 14, as shown in Fig. 6 and Fig. 7, is designed to at least reduce the penetration of dynamic fluid 15, for example splash water, or static fluid 15, for example a water column, from the environment 8 via the through-opening 10a along a second flow direction R2 into the receiving space 2. The Tesla valve 14 is arranged here in a valve housing 16, which forms a drainage channel 17. In the valve housing 16, a check valve 18 in the form of a spring-loaded check valve 19 is also arranged, which releases the drainage channel 17 when there is sufficient flow pressure of the fluid 5 in the direction of the Tesla valve 14. In addition, the check valve 18 blocks, as in Fig. 6 and Fig. 7 shows the penetration of liquid 15, which has entered the drainage channel 17 via the Tesla valve 14. The valve housing 16 is arranged here in the receiving space 2 at the through opening 10a.

[0028] The passive valve, designed as a Tesla valve 14, consists of immovable parts and has a rigid channel system 20 with a main flow channel 21 and loop-shaped secondary flow channels 22. In the first flow direction R1, the liquid 5 flows as the main flow 23 through the main flow channel 21. Only the liquid 15 flowing in the second flow direction R2 flows from the main flow channel 21 into the secondary flow channels 22, which redirect the liquid 15 such that a counterflow 24 is created and blocks the main flow 23 flowing in the main flow channel 21.

Claims

[1] Storage housing (1) for an electrical energy storage device of a motor vehicle, comprising - a plurality of housing walls (3a, 3b, 3c, 3d) which enclose a receiving space (2) for receiving at least one storage component of the electrical energy storage device, wherein at least one of the housing walls (3d) has a through-opening (10a) for discharging a liquid (5) collected in the receiving space (2) into an environment (8) of the storage housing (1), and - at least one valve device (9a) which is designed to drain the liquid (5) from the receiving space (2) into the environment (8) via the through-opening (10a) and to at least reduce the penetration of liquid (15) from the environment (8) into the receiving space (2) via the through-opening (10a), characterized byin that the at least one valve device (9a) has a passive valve with rigid structures (14) arranged in or on the through-opening (10a), which has a first flow resistance in a first flow direction (R1) from the receiving space (2) into the environment (8) and has a second flow resistance which is greater than the first flow resistance in a second flow direction (R2) from the environment (8) into the receiving space (2). [2] Storage housing (1) according to claim 1, characterized by that the passive valve (14) is a Tesla valve. [3] Storage housing (1) according to claim 2, characterized byin that the Tesla valve (14) has a rigid channel system (20) with a main flow channel (21) and loop-shaped, flow-direction-reversing secondary flow channels (22) leading from the main flow channel (21), wherein the Tesla valve (14) is designed to form the different flow resistances by guiding the liquid (5) in the first flow direction (R1) via the main flow channel (21) and by guiding the liquid (15) in the second flow direction (R2) at least partially via the flow-direction-reversing secondary flow channels (22). [4] Storage housing (1) according to one of the preceding claims, characterized by that the at least one valve device (9a) additionally has a check valve (18) which is arranged between the receiving space (2) and the passive valve (14). [5] Storage housing (1) according to claim 4, characterized bythat the check valve (18) is designed as a flow pressure-controlled, spring-loaded check valve (19). [6] Storage housing (1) according to claim 4 or 5, characterized by that the at least one valve device (9a) has a valve housing (16) in which the check valve (18) and the passive valve (14) are arranged and which is arranged in the receiving space (2) of the storage housing (1) at the through opening (10a). [7] Storage housing (1) according to one of the preceding claims, characterized byin that the storage housing (1) has a first through-opening (10a) and a first valve device (9a), which are arranged in a first housing wall (3d) and are designed to discharge liquid (5) from the receiving space (2) in a first flow direction determined by the vehicle acceleration, and at least one second through-opening (10b) and at least one second valve device (9b), which are arranged in a second housing wall (3b) and are designed to discharge liquid (5) from the receiving space (2) in a second flow direction determined by the vehicle acceleration. [8] Storage housing (1) according to claim 7, characterized by that at least one of the housing walls (3a) has at least one liquid reservoir (6) for collecting the liquid (5) in the receiving space (2), from which the liquid emerges due to vehicle acceleration and flows to one of the valve devices (9a, 9b). [9] Storage housing (1) according to claim 8, characterized by that the at least one liquid reservoir (6) is arranged in a bottom-side housing wall (3a) and the through-openings (10a, 10b) and the valve devices (9a, 9b) are arranged in a front-side and a rear-side housing wall (3b, 3d). [10] Storage housing (1) according to one of the preceding claims, characterized by in that the storage housing (1) additionally has an air inlet (11a) and an air outlet (11b) and a fan (12) for generating an air flow (13) from the air inlet (11a) to the air outlet (11b), which is designed to absorb moisture from the receiving space (2) and to transport it into the environment (8) via the air outlet (11b) in order to reduce the liquid (5) in the receiving space (2). [11] Electrical energy storage device comprising at least one storage cell and a storage housing (1) according to one of the preceding claims, wherein the at least one storage cell is arranged in the receiving space (2) of the storage housing (1).

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