Battery housing for an energy storage device, energy storage device for a motor vehicle and method for discharging a gas-particle mixture from a battery housing

Abstract

Battery housing (12) for an energy storage device (10), wherein the battery housing (12) has a receiving area (44) for receiving a battery unit (14; 16, 16a), - wherein a gas discharge channel (26) is integrated into the battery housing (12), which has an interior space (26a) which is spatially delimited by a channel wall (30), - wherein at least one gas inlet opening (32) and at least one gas outlet opening leading out of the battery housing (12) are arranged in the channel wall (30), and a gas discharge path (34) is provided from the at least one gas inlet opening (32) to the at least one gas outlet opening, - wherein the gas discharge channel (26) has at least one particle separation device (28) for separating particles (24) from the gas-particle mixture (22) flowing through the gas discharge channel (26), and - wherein the at least one particle separation device (28) has baffle plates (36) provided by the channel wall (30) and projecting into the interior (26a) of the gas discharge channel (26), which divide the interior (26a) of the gas discharge channel (26) along the gas discharge path (34) into individual segments (38), wherein two segments (38) arranged adjacent to one another along the gas discharge path (34) are fluidically coupled to one another by a through-opening (36a) in the respective baffle plate (36), characterized in that - at least a part of the channel wall (30), which is provided by the baffle plates (36), is designed as a cooling device (46) for cooling a gas-particle mixture (22) flowing through the gas discharge channel (26) and through which a coolant (48) can flow.

Description

[0001] The invention relates to a battery housing for an energy storage device, wherein the battery housing has a receiving area for accommodating a battery unit. Furthermore, the invention also relates to an energy storage device for a motor vehicle and a method for removing a gas-particle mixture escaping from a battery unit from a battery housing.

[0002] A battery cell defect in a battery or battery module can lead to thermal runaway. This process involves the escape of a large amount of gas enriched with very hot particles, known as venting. This gas-particle mixture should be removed from the battery in a controlled manner. The venting gas, also referred to herein as a gas-particle mixture, consists predominantly of flammable components, especially in combination with oxygen.

[0003] If the venting gas escapes from the battery compartment into the environment, the entrained, very hot particles and the mixing with atmospheric oxygen can cause the venting gas to ignite. This can set fire to other parts and components located in the area of ​​the venting gas outlet.

[0004] DE 10 2013 204 585 A1 describes a battery pack, wherein for a degassing situation in which an individual battery cell releases gas from its interior via an overpressure mechanism, for example due to overcharging or thermal overload, a special free space is provided in a battery pack housing, into which the released gas can expand and thereby reduce its temperature and pressure. The gas is then released from the interior of the battery pack housing to the outside via an overpressure release device. The gas flows through a particle separator provided in the overpressure release device, for example in the form of a cyclone separator or a surface filter with a fiber composite or an open-pore, sponge-like structure. Particles contained in the gas, such as graphite dust, can be filtered out as it flows through the particle separator, for example toto avoid explosive concentrations within the escaping gas.

[0005] However, these measures require relatively little space.

[0006] Furthermore, DE 10 2019 114 047 A1 describes a storage module for storing electrical energy, which has a housing enclosing an electrochemical storage cell. The storage module comprises a degassing line arranged on the housing and extending outside the housing, which is designed to discharge exhaust gases from the interior of the housing into the environment of the storage module and thereby cool them. The storage module can comprise a cooling unit to actively cool the degassing line.

[0007] This measure also requires a large amount of additional installation space.

[0008] Furthermore, EP 0 189 543 B1 describes an accumulator in a block box whose individual cells degas via a common gas duct leading to the outside through the block box lid. The collected gas passes through flame-protection devices before escaping to the outside. In particular, two interior chambers are provided, the first of which contains means for acid separation, and the last of which contains a flame-protection device through which the dehumidified gas flows.

[0009] It would nevertheless be desirable to further increase the efficiency of neutralising venting gases, particularly in a way that saves as much space as possible.

[0010] US 2017 / 0 237 055 A1 describes a battery module with a degassing channel and a flow path changer arranged in the degassing channel. This changer extends the flow path of the gas to be discharged by repeatedly changing the flow direction of the gas in a zigzag pattern. The flow path changer comprises several flat plates, each of which has a passage opening for the gas.

[0011] DE 10 2021 100 659 A1 describes a battery housing with an end wall in which a vent opening is formed, and a cover wall, wherein an inner wall divides an interior of the battery housing into an energy storage space and a separation space, wherein a gap is formed between the inner wall and the cover wall, which opens a flow path from the energy storage space through the separation space and the vent opening into an environment, and wherein a separation device with at least one separation element for particles is arranged in the separation space.

[0012] DE 10 2021 102 908 A1 describes an exhaust duct that can be provided by an existing structure of the battery and / or the motor vehicle. The exhaust duct can be provided by a space located between a cooling floor of the battery for cooling the battery cells and an underrun protection of the motor vehicle. The cooling floor can also have cooling channels through which a coolant can flow.

[0013] US 2021 / 0 066 690 A1 describes a gas discharge duct with a pipe and angled guide elements.

[0014] DE 10 2020 125 971 A1 describes a cyclone that can be incorporated into a cooling jacket through which a coolant can flow. Furthermore, a piping element can also be surrounded by the cooling jacket on its outer circumference.

[0015] The object of the present invention is therefore to provide a battery housing, an energy storage device and a method which allow a gas escaping from a battery unit to be discharged from the battery housing in the most efficient and safe manner possible, and in the most space-saving manner possible.

[0016] This object is achieved by a battery housing, an energy storage device, and a method 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.

[0017] A battery housing according to the invention for an energy storage device has a receiving area for receiving a battery unit. A gas discharge channel is integrated into the battery housing, which has an interior space spatially delimited by a channel wall. At least one gas inlet opening and at least one gas outlet opening leading out of the battery housing are arranged in the channel wall, and a gas discharge path is provided from the at least one gas inlet opening to the at least one gas outlet opening. Furthermore, the gas discharge channel has at least one particle separation device for separating particles from the gas-particle mixture flowing through the gas discharge channel.The at least one particle separation device comprises baffle plates provided by the channel wall and extending into the interior of the gas discharge channel, which divide the interior of the gas discharge channel into individual segments along the gas discharge path. Two adjacent segments along the gas discharge path are fluidically coupled to one another through a through-opening in the respective baffle plate. At least a portion of the channel wall provided by the baffle plates is designed as a cooling device for cooling a gas-particle mixture flowing through the gas discharge channel and through which a coolant can flow.

[0018] The invention provides, so to speak, an actively coolable particle separator that is integrated into the battery housing. The combination of an active cooling device with at least one particle separation device results in numerous major advantages. The invention is based on the finding that particle separation leads to a slowing of the corresponding gas-particle mixture in terms of its flow velocity, or that mechanisms that lead to a slowing of the gas-particle mixture can be used for particle separation. This, in turn, results in the gas-particle mixture remaining in the gas discharge channel for longer as it flows through it, which in turn enormously increases the cooling efficiency of the cooling device that cools the gas-particle mixture flowing through the gas discharge channel.The synergistic interaction of cooling and particle separation makes it possible, in a particularly efficient and space-saving manner, to ensure that the venting gas ultimately escaping from the at least one gas outlet contains no or hardly any particles and is also extremely cooled, so that the probability of spontaneous combustion upon escaping into the environment is reduced to a minimum. The efficiency of this gas removal can also be enormously increased by integrating the gas removal duct into the battery housing. This, too, has several reasons: Firstly, for example, by using the battery housing to cool a battery unit accommodated in the battery housing, it can also be used as a cooling device for the gas removal duct, thus again saving components and installation space.Most importantly, this makes it possible to cool the venting gas shortly after it exits the battery unit.

[0019] This can prevent heat buildup and also negative effects on other, still intact battery units. In other words, thermal spread to other battery units can be prevented or at least delayed much more effectively. Overall, the invention thus provides a particularly efficient and safe, yet space-saving, way of removing a venting gas from a battery housing.

[0020] The battery housing can be a battery housing for a motor vehicle battery, preferably for a high-voltage battery. The battery unit that can be accommodated in the battery housing can be, for example, a single battery cell, for example a lithium-ion cell, or else a battery module or a cell stack with several such battery cells. The battery housing can also be designed to accommodate several such battery units, in particular several battery cells or several battery modules, each with several battery cells. For this purpose, the battery housing can also have several receiving areas, each for receiving a battery unit. Several such gas discharge channels can also be arranged in the battery housing, for example on different sides of the one or more receiving areas. Preferably, the gas discharge channel is also arranged in an edge region of the battery housing.This facilitates the gas discharge to the outside and the spatial and thermal separation of the battery cells that can be accommodated in the battery housing when accommodated. The battery housing can, for example, be essentially box-shaped, i.e. cuboid-shaped. The interior of the battery housing can, for example, be divided into a first region in which the receiving regions for the battery units are provided, and a second region in which the gas discharge channel is arranged. The second region is to be provided significantly smaller, in particular by orders of magnitude, than the first region. The two regions can, for example, be separated by a partition wall in which the at least one gas inlet opening is arranged. In addition, if the battery housing has several receiving regions, it can also have several such partition walls that separate the individual receiving regions from one another at least in some regions.For example, the battery housing can be designed as a die-cast aluminum component. Accordingly, it is preferred that the channel wall of the gas discharge channel is also made of a metallic material, for example, aluminum. This has the great advantage that the heat from the particle-gas mixture can be absorbed and dissipated very quickly. The particle separation device itself can also be considered part of the channel wall. In particular, any surface with which the gas-particle mixture can come into contact as it flows through the gas discharge channel along the gas discharge path can be considered a channel wall. The part of the channel wall designed as a cooling device can therefore also be subjected to flow or contact by the gas-particle mixture flowing through the gas discharge channel. This allows the gas-particle mixture to be cooled particularly efficiently.Preferably, the cooling device is also designed as an active cooling device. A coolant, e.g., water, can be used to cool at least part of the channel wall.

[0021] According to the invention, at least one part of the channel wall is designed such that a coolant can flow through it. The at least one part of the channel wall can therefore have one or more cooling channels through which such a coolant can flow. The coolant is preferably a water-based coolant, as can also be used, for example, for cooling the battery unit when the battery unit is accommodated as intended in the battery housing and the energy storage device provided in this way is operated as intended in a motor vehicle. Such active cooling allows significantly more heat to be dissipated and the gas-particle mixture to be cooled much more efficiently than, for example, solely through expansion cooling or the like. Furthermore, it is conceivable that only part of the channel wall or some parts of the channel wall that delimit the interior of the gas discharge channel are designed such that a coolant can flow through it.

[0022] In principle, however, it is also possible to design the entire channel wall so that a coolant can flow through it.

[0023] The cooling device can, for example, only become active when the escape of a gas-particle mixture, which for the sake of simplicity is also referred to simply as gas or venting gas, is detected as a battery unit accommodated in the battery housing. If the cooling device also serves to cool or regulate the temperature of one of the battery units during normal operation, the cooling device may already be active before a venting gas escapes from the battery unit and therefore no longer needs to be activated separately. Activation of the cooling device should be understood to mean at least the activation of a coolant pump, which can be fed, for example, via a low-voltage network of a motor vehicle in which the invention is used.Active cooling of the coolant via a refrigerant circuit can also be the case, at least if this is still possible in this case despite the defect in the energy storage device.

[0024] In a further very advantageous embodiment of the invention, the battery housing has a partition wall that separates the receiving area from the interior of the gas discharge channel, wherein the partition wall provides a further part of the channel wall through which the coolant can flow. This represents a particularly advantageous embodiment of the invention, since the partition wall, which now represents the cooling device, can thus be used not only to cool the gas-particle mixture flowing through the gas discharge channel, but during normal operation, simultaneously also to cool the battery unit accommodated in the receiving area. During normal operation, the cooling device for cooling the gas-particle mixture flowing through the gas discharge channel is therefore not unused.Another major advantage is that this actively cooled partition wall provides particularly good thermal decoupling of the hot gas-particle mixture from the receiving area(s) and thus from the battery units arranged in the receiving areas. This is particularly beneficial for still intact battery units housed in the battery housing. This prevents, or at least significantly more effectively delays, the thermal runaway of a battery unit from spreading to other battery units.

[0025] According to the invention, at least a portion of the particle separation device is designed to allow the coolant to flow through it, with the at least one portion of the particle separation device being provided by the at least one portion of the channel wall designed as a cooling device. Thus, it is advantageously possible to also design the particle separation device itself as an active cooling device. This also makes particle separation even more efficient. Cooling the gas-particle mixture also extracts energy from the particles contained in the gas-particle mixture and slows them down, which simplifies separation.

[0026] The particle separation device can generally take various forms. For example, it can be designed as a particle filter with a filter material and / or as a centrifuge or cyclone separator. Furthermore, the gas discharge channel can also comprise several different such particle separation devices. Such a particle separation device can also be provided, for example, by the gas discharge path from the at least one gas inlet opening to the at least one gas outlet opening not running in a straight line, but rather having numerous turns and deflections.

[0027] According to the invention, the at least one particle separation device comprises baffle plates provided through the channel wall, projecting into the interior of the gas discharge channel, which divide the interior of the gas discharge channel into individual segments along the gas discharge path, wherein two adjacent segments along the gas discharge path are fluidically coupled to one another by a through-opening in the respective baffle plate. These baffle plates thus cause a local cross-sectional reduction of the flow cross-section of the gas discharge channel. A large portion of the gas-particle mixture flowing along the gas discharge path thus impacts these baffle plates and is thereby decelerated and swirled. These swirls lead to a further deceleration of the gas flow. The impact on the baffle plates and the deceleration of the gas flow result in particles contained in the gas flow being deposited on these baffle plates.Each time the particle passes through a through-opening of such a baffle plate and a corresponding segment, additional particles are gradually separated, and the gas flow is progressively slowed. This slowing also results in a cooling of the gas flow, independent of the additional active cooling of the channel wall. This allows for particularly efficient cooling and particle separation of the venting gas.

[0028] As already defined above, the baffle plates also represent a part of the channel wall of the discharge channel. Accordingly, the above-mentioned part of the channel wall, which is designed as a cooling device, is precisely these baffle plates.

[0029] In a further very advantageous embodiment of the invention, a respective through-opening is located in an upper half of a respective baffle plate with respect to a first direction. The first direction is preferably defined such that it is aligned parallel to a vertical direction of the vehicle when the battery housing is arranged as intended in a motor vehicle. The fact that the respective through-openings in the respective baffle plates are then arranged in the upper half of a respective baffle plate has the great advantage that particles deposited on the baffle plates generally sink downwards due to gravity. However, this does not inhibit the flow through the baffle plates or their through-openings, since these are located in the upper half of a respective baffle plate.In other words, the passage openings cannot then be clogged and blocked by particles that settle and separate in them.

[0030] According to a further advantageous embodiment of the invention, the gas discharge channel has, at least in some regions, a longitudinal extension in a second direction that is perpendicular to the first direction, and wherein a third direction is defined perpendicular to the first and second directions. The through-openings of two impact plates adjacent in the second direction are arranged offset from one another in the third direction. In other words, the through-openings of two impact plates adjacent in the second direction are not arranged concentrically to one another, i.e., they are not aligned. This has the advantage that it is not possible for the gas-particle mixture to flow straight through the through-openings in the second direction. The gas flow must first be deflected in order to flow through the closest through-opening in the second direction. This in turn promotes particle separation and cooling of the venting gas.

[0031] The gas discharge channel itself can also be designed with multiple windings and, for example, run in the second direction and then be deflected so that it continues to run opposite to the second direction, and so on. The gas discharge channel can therefore run in a serpentine manner with regard to its main direction of extension, and the gas discharge path within the gas discharge channel can, for example, run again separately in a serpentine shape. In the deflection regions of the gas discharge channel, the gas discharge channel then runs partly not in the second direction, but partly also in the third direction. In general, it can therefore be provided that the through-openings of two baffle plates adjacent in the longitudinal direction of the gas discharge channel are offset from one another in a direction perpendicular to this longitudinal direction, regardless of whether the longitudinal direction currently points in the second direction or not, or, for example,in the third direction.

[0032] In a further very advantageous embodiment of the invention, the baffle plates are at least partially arranged at an angle other than 90 degrees to the second and third directions. In general, a baffle plate does not necessarily have to be flat; rather, it can already be angled. At least a portion of such a baffle plate is therefore preferably oriented neither perpendicular to the second direction nor perpendicular to the third direction. This applies in particular to baffle plates arranged in a portion of the gas discharge channel that runs in the second direction.

[0033] It has been shown that this angled design and arrangement of the baffles allows the venting gas flowing through the gas discharge channel to be swirled particularly vigorously. Such swirls have a similar effect to, for example, a cyclone separator. Due to the resulting centrifugal forces, particles contained in the venting gas are thrown outward and separated. The efficiency of particle separation can thus be further increased.

[0034] The design of the at least one particle separation device as such impact plates can also be combined with other particle separation devices, for example with one or more of the above-mentioned cyclone separators.

[0035] Furthermore, the invention also relates to an energy storage device for a motor vehicle, which has a battery housing according to the invention or one of its embodiments.

[0036] The energy storage device is preferably designed as a high-voltage battery. In addition to the battery housing, such an energy storage device preferably comprises at least one battery unit, which is accommodated in the receiving area of ​​the battery housing. The battery housing preferably comprises a plurality of receiving areas, in each of which a battery unit can be arranged. In other words, it is preferred that the energy storage device comprises a plurality of energy units. The battery units can be battery cells or battery modules, which in turn each comprise a plurality of battery cells. The battery cells can be designed as prismatic cells, pouch cells, or round cells. In addition, the battery cells can be designed, for example, as lithium-ion cells.

[0037] Furthermore, a motor vehicle with an energy storage device according to the invention or one of its embodiments is also considered to be part of the invention. The motor vehicle can be designed as a purely battery-powered electric vehicle or as a hybrid vehicle.

[0038] The motor vehicle according to the invention is preferably designed as a motor vehicle, in particular as a passenger car or truck, or as a passenger bus or motorcycle.

[0039] Furthermore, the invention relates to a method for discharging a gas-particle mixture escaping from a battery unit from a battery housing having a receiving area in which the battery unit is accommodated. A gas discharge channel is integrated into the battery housing, said gas discharge channel having an interior space defined by a channel wall. The gas-particle mixture escaping from the battery unit is fed to the gas discharge channel through at least one gas inlet opening in the channel wall and guided along a gas discharge path to at least one gas outlet opening leading out of the battery housing. Particles are separated from the gas-particle mixture flowing through the gas discharge channel by means of a particle separation device in the gas discharge channel.The particle separation device comprises baffle plates provided by the channel wall and extending into the interior of the gas discharge channel. These baffle plates divide the interior of the gas discharge channel into individual segments along the gas discharge path. Two adjacent segments along the gas discharge path are fluidically coupled to one another by a through-opening in the respective baffle plate. Furthermore, the gas-particle mixture flowing through the gas discharge channel is cooled by at least one part of the channel wall designed as a cooling device, which is provided by the baffle plates and through which a coolant flows.

[0040] Here too, the advantages mentioned in connection with the battery housing according to the invention and its configurations apply equally to the method according to the invention.

[0041] The invention also includes further developments of the method according to the invention that have features already described in connection with the further developments of the battery housing according to the invention. For this reason, the corresponding further developments of the method according to the invention are not described again here.

[0042] The invention also encompasses combinations of the features of the described embodiments. The invention therefore also encompasses implementations that each comprise a combination of the features of several of the described embodiments, unless the embodiments are described as mutually exclusive.

[0043] Exemplary embodiments of the invention are described below. Shown are: Fig. 1 a schematic representation of a part of a high-voltage battery with a battery housing in a plan view according to an embodiment of the invention; Fig. 2 a schematic representation of a baffle plate of a particle separation device for a battery housing according to an embodiment of the invention; Fig. 3 is a schematic representation of a part of a gas discharge channel of a battery housing in a plan view according to an embodiment of the invention; and Fig. 4 a schematic cross-sectional view of the high-voltage battery from Fig. 1 according to an embodiment of the invention.

[0044] The exemplary embodiments explained below are preferred embodiments of the invention. In the exemplary embodiments, the described components of the embodiments each represent individual features of the invention that can be considered independently of one another, each of which also develops the invention independently of one another. Therefore, the disclosure is intended to encompass combinations of the features of the embodiments other than those shown. Furthermore, the described embodiments can also be supplemented by further features of the invention already described.

[0045] In the figures, the same reference symbols designate elements with the same function.

[0046] Fig. Figure 1 shows a schematic representation of a part of a high-voltage battery 10 with a battery housing 12 according to an exemplary embodiment of the invention. The battery housing 12 is manufactured here as a battery box, for example, as a die-cast aluminum housing. The high-voltage battery 10 in turn comprises a plurality of battery modules 14, of which Fig. 1 only a part of such a battery module is shown. Such a battery module 14 comprises several battery cells 16, of which Fig. 1, for reasons of clarity, only some are provided with a reference symbol. In this example, the battery cells 16 are designed as prismatic battery cells. The high-voltage battery 10 is preferably arranged in a motor vehicle such that the z-direction shown here points in the direction of a vehicle's vertical axis. Accordingly, the illustration in Fig. 1 shows a view of the top side of the respective battery cells 16. On this top side, the respective battery cells 16 also each have a vent opening 18. This is normally closed and is opened when a battery cell vents. For example, such a vent opening 18 can be designed as a bursting membrane or similar. In the event of a cell defect, a thermal runaway of such a cell 16 can occur. Fig. 1 shows such a thermal runaway 20 as an example for a first cell 16a of the battery cells 16 of the high-voltage battery 10. A very hot gas-particle mixture 22 escapes from the cell 16a. This gas-particle mixture 22 is also referred to below as venting gas 22. This venting gas 22 therefore includes hot particles 24.

[0047] If such a venting gas escapes from the battery compartment of conventional batteries into the environment, the entrained, very hot particles and the mixing with atmospheric oxygen can cause the venting gas to ignite. This can set fire to other parts and components located in the area of ​​the venting gas outlet.

[0048] This can now advantageously be prevented, or the risk thereof at least enormously reduced, by integrating a gas discharge channel 26 into the battery housing 12. The gas discharge channel 26, which on the one hand has a particle separation device 28 and which can also be actively cooled, has an interior 26a that is spatially delimited by a channel wall 30. The channel wall 30 therefore includes any surface of the gas discharge channel 26 that can come into contact with the venting gas 22 conducted through the gas discharge channel 26. The gas discharge channel 26 has at least one inlet opening 32 through which the venting gas 22 escaping from the defective battery cell 16a can enter the gas discharge channel 26.Furthermore, in the present example, the gas discharge channel 26 also has an outlet opening (not shown in detail), through which the venting gas 22 can exit the battery housing 12 after passing through the gas discharge channel 26. The venting gas 22 is guided along a gas discharge path 34 as it passes through the gas discharge channel 26. The gas discharge path shown in FIG. Fig. The arrows shown in Figure 1 thus illustrate the venting gas 22 and the gas discharge path 34 in the same way. The guidance of the venting gas 22 along this gas discharge path 34 is determined by the geometric design of the gas discharge channel 26.

[0049] At least a portion of the channel wall 30 is designed as a cooling device. In particular, at least a portion of this channel wall 30 is designed with cooling channels through which a coolant can flow. This allows the venting gas 22 guided through the gas discharge channel 26 to be cooled particularly efficiently. In addition, the gas discharge channel 26, as already mentioned, comprises a particle separation device 28. In this example, this is designed as a plurality of baffle plates 36. These baffle plates 36 divide the gas discharge channel 26 into a plurality of segments 38. For reasons of clarity, these are also shown in Fig. 1, only a few are provided with a reference symbol. Each baffle plate 36 has a through-opening through which the venting gas 22 flowing in the gas discharge channel 26 can pass. Thus, two adjacent segments 38 of the gas discharge channel 26 are fluidically connected to one another through such an opening.

[0050] Fig. Figure 2 shows a schematic representation of such a baffle plate 36 in a top view, i.e. perpendicular to the x-direction shown here. In the present example, the x-direction also corresponds to the main extension direction of the gas discharge channel 26, which, as shown in Fig. 1, runs in and against the x-direction and is also deflected several times. As shown in Fig. 2, such a baffle plate 36 has a through-opening 36a through which the venting gas 22 (compare Fig. 1) can pass through. The dashed lines 40 in Fig. 2 indicate limitations of the through-opening 36a upwards and to the side, which are provided by parts of the wall 30 of the gas discharge channel 26, for example by a top cover of the battery housing 12 and by a lateral partition wall 42 (cf. Fig. 1). By means of such partition walls 42, the individual segments 38 of the gas discharge channel 26 are separated from each other in the y-direction, as is also shown in Fig. 1, as well as the gas discharge channel 26 from the adjacent receiving area 44, in which the battery module 14 is accommodated. This is also shown, for example, in Fig. 4 can be recognized.

[0051] Fig. 4 shows a schematic cross-sectional view of a cross section of the energy storage device 10 from Fig. 1 perpendicular to the x-direction. This partition 42 between the receiving area 44, in which the battery module 14 is arranged, and the gas discharge channel 26 is designed in the present example as the cooling device 46 and is flowed through by a coolant 48, for example water or a water-antifreeze mixture. This partition 42 simultaneously also represents part of the wall 30 of the gas discharge channel 26. This actively cooled partition 42 advantageously performs a dual function. On the one hand, it can be used to cool the venting gas 22, which flows through the gas discharge channel 26, but at the same time, during normal operation, it can also be used to cool and temperature-regulate the battery module 14. Fig. 4 also shows a pole 50 or terminal 50 of the battery cell 16a. The routing of the venting gas 22 from the venting opening 18 of the battery cell 16a to the inlet opening 32 of the gas discharge channel 26 is designed such that the venting gas is separated from the pole terminal 50. This can be achieved by introducing the venting gas 22, after exiting the venting opening 18, into a separate spatial area, which is particularly separate from the cell poles 50.

[0052] As also in Fig. 2, the passage openings 36a in the respective baffle plates 36 are arranged in the upper half of such a baffle plate 36. By the venting gas 22 hitting such a baffle plate 36, it is slowed down and the particles 24 contained in the venting gas 22 (see Fig. 1) are separated. These accumulate in the soil due to gravity, as is also the case in Fig. 1. By arranging the through-openings 36a of the baffle plates 36, as shown in Fig. 2, in the upper half of each of such a baffle plate 36, it can be achieved that these openings 36a are not clogged or blocked by the separated particles 24. Furthermore, it is preferred that these openings 36a of each two adjacent baffle plates 36 are offset from each other perpendicular to the flow direction or are not aligned. This ensures that the venting gas 22 cannot spread in a straight line or can simply flow straight through these openings 36a without deflection. On the contrary, this offset arrangement of the openings 36a ensures that the venting gas 22 is deflected several times, as is also the case in Fig. 1. The venting gas 22 thus follows a kind of wave-like path. This creates additional turbulence, which leads to increased particle deposition.

[0053] Fig. Figure 3 again shows part of a gas discharge channel 26 in a plan view in the z-direction according to another embodiment of the invention. This gas discharge channel 26 is also formed with the described baffle plates 36. The gas discharge channel 26 can also be formed as already described. The through-openings 36a in a respective baffle plate 36 are in Fig. 3 is also illustrated by a dashed line. The baffle plates 36 can also be used as a whole or only partially, as for example in the example in Fig. 3, be aligned at an angle to the x-direction and the y-direction that is different from 90 degrees. This angled design further enhances the generation of turbulence. These turbulences are also shown as examples in Fig. 3 and designated 52. Furthermore, it is possible for active cooling to occur not only through the partition walls 42 but also through the baffle plates 36 themselves. This further increases the cooling efficiency. For example, areas of the partition walls 42 and the baffle plates 36 can also be surrounded by the coolant 48 in a meandering pattern (see Fig. 4) are flowed through.

[0054] In addition to this embodiment of the particle separator 28 with such impact plates 36, the gas discharge channel 26 can also be additionally provided with other separation mechanisms, for example, a cyclone separator or filter materials or the like. In this case, too, parts of such a cyclone separator can be designed to allow a coolant 48 to flow through them. In other words, wall sections of such a cyclone separator can also be designed as active cooling devices 46.

[0055] Overall, the examples demonstrate how the invention can provide a battery with a cooled venting gas particle separator. Preferably, a separation chamber is integrated within the battery. The venting gas is guided through this separation chamber before it comes into contact with the ambient air. Through multiple deflections of the gas flow, combined, for example, with baffle plates, filter materials, centrifuges, and so on, the very hot particles are separated from the gas and simultaneously retained in the separation chamber. In addition, the battery's coolant flows through the separation chamber, or areas thereof, which are made of highly thermally conductive material. This prevents the venting gas from igniting upon contact with atmospheric oxygen due to very hot particles.Furthermore, the venting gas is cooled, slowed down by the resulting volume reduction and brought below the autoignition temperature before escaping into the ambient air.

Claims

[1] Battery housing (12) for an energy storage device (10), wherein the battery housing (12) has a receiving area (44) for receiving a battery unit (14; 16, 16a), - wherein a gas discharge channel (26) is integrated into the battery housing (12), which has an interior space (26a) which is spatially delimited by a channel wall (30), - wherein at least one gas inlet opening (32) and at least one gas outlet opening leading out of the battery housing (12) are arranged in the channel wall (30), and a gas discharge path (34) is provided from the at least one gas inlet opening (32) to the at least one gas outlet opening, - wherein the gas discharge channel (26) has at least one particle separation device (28) for separating particles (24) from the gas-particle mixture (22) flowing through the gas discharge channel (26), and - wherein the at least one particle separation device (28) has baffle plates (36) provided by the channel wall (30) and projecting into the interior (26a) of the gas discharge channel (26), which divide the interior (26a) of the gas discharge channel (26) along the gas discharge path (34) into individual segments (38), wherein two segments (38) arranged adjacent to one another along the gas discharge path (34) are fluidically coupled to one another by a through-opening (36a) in the respective baffle plate (36), characterized by , that - at least a part of the channel wall (30), which is provided by the baffle plates (36), is designed as a cooling device (46) for cooling a gas-particle mixture (22) flowing through the gas discharge channel (26) and through which a coolant (48) can flow. [2] Battery housing (12) according to claim 1, characterized byin that the battery housing (12) has a partition wall (42) which separates the receiving area (44) from the interior (26a) of the gas discharge channel (26), wherein the partition wall (42) provides a further part of the channel wall (30) through which the coolant (48) can flow. [3] Battery housing (12) according to one of the preceding claims, characterized by that a respective through-opening (36a) is located in an upper half of a respective baffle plate (36a) with respect to a first direction (z). [4] Battery housing (12) according to claim 3, characterized byin that the gas discharge channel (26) has, at least in some regions, a longitudinal extension in a second direction (x) which is perpendicular to the first direction (z), and wherein a third direction (y) is defined perpendicular to the first and second directions (z, x), wherein the through openings (36a) of two baffle plates (36) adjacent in the second direction (x) are arranged offset from one another in the third direction (y). [5] Battery housing (12) according to one of the preceding claims, characterized by that the impact plates (36) are at least partially arranged at an angle different from 90 degrees to the second and third directions (x, y). [6] Energy storage device (10) for a motor vehicle, which has a battery housing (12) according to any preceding claim. [7] Method for discharging a gas-particle mixture (22) emerging from a battery unit (14; 16, 16a) from a battery housing (12) which has a receiving area (44) in which the battery unit (14; 16, 16a) is received, wherein a gas discharge channel (26) is integrated into the battery housing (12), which has an interior space (26a) which is spatially delimited by a channel wall (30), wherein the gas emerging from the battery unit (14;16, 16a) is fed through at least one gas inlet opening (32) in the channel wall (30) to the gas discharge channel (26) and is guided along a gas discharge path (34) to at least one gas outlet opening leading out of the battery housing (12), wherein by means of a particle separation device (28) of the gas discharge channel (26) particles (24) are separated from the gas-particle mixture (22) flowing through the gas discharge channel (26), wherein the particle separation device (28) has baffle plates (36) provided by the channel wall (30) and projecting into the interior (26a) of the gas discharge channel (26), which baffle plates divide the interior (26a) of the gas discharge channel (26) along the gas discharge path (34) into individual segments (38), wherein two along segments (38) arranged adjacent to the gas discharge path (34) are fluidically coupled to one another by a through-opening (36a) in the respective baffle plate (36); characterized bythat the gas-particle mixture (22) flowing through the gas discharge channel (26) is cooled by at least one part of the channel wall (30) designed as a cooling device (46), which part is provided by the baffle plates (36) and through which a coolant (48) flows.

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