Battery for motor vehicle and motor vehicle

Abstract

The invention relates to a battery (10) for a motor vehicle, comprising a plurality of battery cells (12) and a battery housing (14), which encloses a housing interior (16), in which the battery cells (12) are accommodated, and which has an orifice plate (20) on which the battery cells (12) rest, according to the invention, the orifice plate (20) has, for each battery cell (12), an associated vent opening (28) on which the associated battery cell (12) rests and via which the gas discharged from the respective associated battery cell (12) can be discharged from the housing interior (16).

Description

Technical Field

[0001] The invention relates to a battery for a motor vehicle and a motor vehicle having a battery. Background Art

[0002] DE 10 2019 206 646 A1 discloses an energy storage housing device for a motor vehicle, which has an energy storage housing and an underbody protection plate fixed to the energy storage housing on the underside. The underbody protection plate has a sandwich arrangement, which has an upper cover plate on its upper side facing the energy storage housing and a lower cover plate on its underside, wherein a filler is arranged between the upper cover plate and the lower cover plate and the upper side of the sandwich arrangement has a profiled profile for the strips or ribs.

[0003] DE 10 2011 103 993 A1 discloses a battery with a plurality of battery cells, which are connected to a cooling element at at least one of their end sides via an elastic tolerance compensation element, wherein an electrically insulating film is arranged between the battery cell and the cooling element. It is provided that the insulating film and the tolerance compensation element are designed to be integral or to be connected to one another in a materially bonded manner.

[0004] Furthermore, DE 10 2019 200 465 A1 discloses a battery module device having a plurality of battery cells, each of the plurality of battery cells having a cell opening formed therein, and a plate arrangement defining a chamber, the chamber containing a fluid therein. Furthermore, the battery module device comprises a plurality of openings extending through the plate arrangement, wherein each of the plurality of openings is arranged to align with a cell opening of one of the battery cells.

[0005] Furthermore, WO 2022 / 031056 A discloses a battery module, and DE 10 2017103 654 B4 discloses a battery housing for a vehicle battery. Summary of the invention

[0006] The object of the present invention is to provide a solution which allows a particularly reliable removal of hot gases from a battery cell in the event of a thermal runaway of the battery cell.

[0007] This task is solved by the technical solution of the independent claim. Other possible embodiments of the invention are disclosed in the dependent claims, the description and the drawings. The features, advantages and possible embodiments described for one of the technical solutions of the independent claim within the scope of the description should at least be regarded as similar to the features, advantages and possible embodiments of the corresponding technical solutions of the other independent claims and any possible combination of the technical solutions of the independent claims - possibly in combination with one or more of the dependent claims.

[0008] The present invention relates to a battery for a motor vehicle, which is arranged to provide electric drive energy for an electric powertrain of the motor vehicle. This means that the motor vehicle can be driven by electric energy from the battery. In particular, the battery can be a high-voltage accumulator of the motor vehicle. The battery has a plurality of battery cells and a battery housing. The battery housing surrounds an inner space of the housing, in which each battery cell is accommodated. In addition, the battery housing has a perforated plate, on which the battery cell is placed. "The battery cell is placed on the perforated plate" can be understood as: the weight of the battery cell is borne by the perforated plate. In the prescribed installation position of the battery in the motor vehicle, the battery cell is therefore arranged above the perforated plate in the vertical direction of the vehicle. The battery cell can be placed directly on the perforated plate or indirectly on the perforated plate via at least one other component. The cover of the battery housing forms a sandwich structure with the perforated plate and the battery cell arranged therebetween. The particularly high overall rigidity of the battery can be achieved by the sandwich structure.

[0009] The perforated plate has a matching exhaust opening for each battery cell, and the matching battery cell is placed on the exhaust opening. The gas discharged from the corresponding matching battery cell can be discharged from the housing interior space via the exhaust opening. Since the corresponding battery cell is placed on the perforated plate and arranged above the perforated plate in the vertical direction of the vehicle in a prescribed installation position, the gas generated when the battery cell thermally runs away can be discharged downward from the battery. By discharging the generated gas downward in this way, the risk of these gases invading the passenger compartment of the motor vehicle can be particularly reduced. In addition, when the battery is arranged in the vehicle floor area of ​​the motor vehicle, the gas can be discharged from the motor vehicle over a particularly short path by discharging the gas downward from the corresponding battery cell.

[0010] Thermal runaway of battery cells and the propagation of heat, the spread of thermal events in the battery from battery cell to battery cell, are among the greatest safety challenges in the operation of lithium-ion batteries, such as their increasing use in the growing field of electric vehicles. Heat propagation can be particularly effectively prevented by providing the perforated plate with exhaust openings to discharge the hot gases generated in the case of thermal runaway of the battery cells out of the battery cells.

[0011] Each of the battery cells can completely cover the corresponding exhaust opening upward in the vertical direction of the vehicle, thereby preventing gas from flowing back into the interior space of the housing through the exhaust opening. In addition, the gas blow-out opening arranged on the lower side of the battery cell can be reliably arranged above the corresponding exhaust opening. This ensures that a particularly large part of the gas generated when the battery cell thermally runs away, in particular all of the gas generated, can be reliably discharged from the battery cell through the exhaust opening and thus prevent the gas from entering the interior space of the housing particularly safely. In particular, the corresponding exhaust opening can be aligned with the gas blow-out opening of the corresponding corresponding battery cell.

[0012] In the present invention, it is provided that a gap is formed between the battery cell and the orifice plate, the battery cell is surrounded by foam in the housing interior space and the foam closes the gap and the exhaust opening. With the help of this foam, the volume of the housing interior space that is not filled by the battery cell or the electronic device can be filled, so that all the components of the battery can be safely maintained in their corresponding positions within the housing interior space. The foam also enters the gap between the corresponding battery cell and the matching exhaust opening and closes the exhaust opening of the orifice plate. The foam can harden in these exhaust openings of the orifice plate, thereby providing a sealing layer. The foam is configured to melt when in contact with the hot gas discharged from the corresponding battery cell, so that the exhaust opening closed by the foam can be released to guide the gas out of the housing interior space. Therefore, with the help of foam, all the components of the battery can be fixed in the housing interior space, and the exhaust opening can also be sealed, especially watertightly sealed.

[0013] Alternatively or additionally, it is provided that the impact-absorbing foam is bonded to the side of the perforated plate opposite the battery cells. By bonding the impact-absorbing foam to the perforated plate, the impact-absorbing foam can be held particularly securely on the perforated plate. In particular, if the battery is designed with both the impact-absorbing foam bonded to the perforated plate and the pot, the pot can be replaced particularly easily because the impact-absorbing foam is securely held on the perforated plate.

[0014] In a possible further development of the invention, it is provided that the perforated plate is formed from steel or aluminum. An aluminum perforated plate has a particularly low weight. A steel perforated plate has a particularly high stability and rigidity and thus a particularly long service life. It is also possible that the perforated plate has both steel and aluminum.

[0015] In another possible embodiment of the present invention, it is provided that the exhaust opening is sealed by means of a sealing layer, in particular, sealed watertightly. The sealing layer is arranged to be penetrated by hot gases flowing out of the battery cell during thermal runaway. Thermal runaway refers to the ignition or explosion of a battery cell due to an exothermic reaction in the corresponding battery cell. In order to avoid a chain reaction from multiple battery cells of the battery to all battery cells and thereby suppress the occurrence of a self-sustaining reaction, the gas generated during thermal runaway of a single battery cell is discharged via a matching exhaust opening. In order to ensure the sealing of the internal space of the housing during normal operation of the battery, in particular, the sealing relative to water to avoid water from entering the internal space of the housing, a sealing layer is provided. Therefore, the sealing layer together with the perforated plate provides corresponding predetermined rupture sites, and the exhaust opening is closed by means of these predetermined rupture sites during normal operation, and the matching exhaust opening is opened by means of hot gases via these predetermined rupture sites in the case of thermal runaway. For this opening, the hot gas at least partially melts the sealing layer, so that the gas can be discharged from the internal space of the housing via the released exhaust opening. The sealing layer thus makes it possible that the battery cells are particularly well protected against the ingress of water and that, in addition, in the event of a thermal runaway of at least one of the battery cells, hot gases can be safely discharged via corresponding ventilation openings of the perforated plate.

[0016] In another possible embodiment of the present invention, it is provided that the sealing layer has an adhesive layer, via which the battery cell is bonded to the orifice plate, and / or the sealing layer has at least one plastic element, which is attached to the orifice plate. In other words, an adhesive can be applied to the orifice plate, which is used to close the corresponding exhaust openings of the orifice plate on the one hand and to bond the battery cell to the orifice plate on the other hand. Therefore, the adhesive can achieve a seal, in particular a watertight seal of the housing interior space on the one hand and a safe fixation of the battery cell in the housing interior space on the other hand. The battery cell can be safely held on the orifice plate via the adhesive, thereby suppressing the relative movement of the battery cells to each other or to the battery housing, so that the risk of battery cell damage is particularly low. For example, the plastic element can be a corresponding plastic plug, which is inserted into the corresponding exhaust opening of the orifice plate to close the exhaust opening. Alternatively, the plastic element can be a plastic plate, which is attached to the orifice plate on the side of the orifice plate facing the housing interior space or on the side of the orifice plate facing away from the housing interior space, thereby covering and sealing at least one, in particular multiple, in particular all exhaust openings of the orifice plate by means of a plastic cup. If only one plastic element is provided, this plastic element can seal all exhaust openings of the orifice plate. If multiple plastic elements are provided to provide the sealing layer, each of these plastic elements seals at least one exhaust opening, in particular multiple exhaust openings, of the orifice plate. In the event of thermal runaway of the associated battery cell, the adhesive layer or the plastic element melts at least partially due to contact with the generated hot gases, thereby releasing the associated exhaust opening of the orifice plate. The hot gases can escape through the released exhaust openings.

[0017] In another possible embodiment of the present invention, it is provided that a basin is arranged on the side of the perforated plate opposite to the battery cell, and the basin surrounds a buffer volume together with the perforated plate, in which impact-absorbing foam is arranged. The basin can provide lower floor protection for the battery or the motor vehicle together with the impact-absorbing foam. The impact-absorbing foam can be implemented specifically for the vehicle and can be used for different high-voltage accumulators. Alternatively or additionally, the impact-absorbing foam can also be implemented specifically for the accumulator and used for different vehicles. The impact-absorbing foam is provided to protect the perforated plate from mechanical damage such as scratches and thus from corrosion. The basin can be made of metal or fiber-reinforced plastic in particular. For example, the basin has a sandwich structure composed of two components stacked on each other and made of a fiber-reinforced plastic, in particular a spacer between these components, and a filling foam. The impact-absorbing foam is provided to deform in the event of a collision, thereby converting kinetic energy into deformation energy. The battery cell of the battery can thus be particularly well protected from damage. The basin is provided to hold the impact-absorbing foam. In addition, the basin is provided to block the impact from below in the installation position of the battery in the motor vehicle. The basin and the impact-absorbing foam thus enable a particularly long service life of the battery cells by particularly well protecting the battery cells from damage. In addition, hot gases generated in the event of thermal runaway of the battery cells can be vented via the venting openings of the perforated plate into the buffer volume. In this buffer volume, the gases generated in the event of thermal runaway of the at least one battery cell can be collected and discharged from the battery cell. In order to discharge the hot gases from the battery cells, corresponding guide channels can be provided in the impact-absorbing foam.

[0018] In this case, it can be provided in particular that the pot is connected sealingly to the perforated plate. This means that the buffer volume is sealed by the perforated plate (especially if a sealing layer is present) and the pot. An unintentional escape of hot gas from the buffer volume can thus be avoided.

[0019] In another possible embodiment of the invention, it is provided that the basin is reversibly held on the battery housing. In particular, the basin can be replaced without destruction. Therefore, in particular in the case of damage to the basin, the damaged basin can be removed from the battery housing particularly easily and a new basin can be arranged and fixed on the battery housing. Therefore, it is not necessary to completely replace the entire battery if only the basin is damaged. As a result, the service life of the battery is particularly long and the battery can be repaired particularly easily.

[0020] The invention also relates to a motor vehicle having a battery as has already been described in conjunction with the battery according to the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Further features of the invention can be derived from the claims, the drawings and the description of the drawings. The features and feature combinations mentioned above in the description and the features and feature combinations shown below in the description of the drawings and / or individually in the drawings can be used not only in the respectively given combination but also in other combinations or individually without leaving the scope of the invention.

[0022] In the figure:

[0023] Figure 1 A cross-sectional view showing a portion of a battery for a motor vehicle;

[0024] Figure 2 showing an enlarged portion of the cross-sectional view; and

[0025] Figure 3 A schematic perspective view showing an aperture plate of a battery. DETAILED DESCRIPTION

[0026] In the figures, identical elements and elements having the same function are provided with the same reference symbols.

[0027] exist Figure 1 1 shows a battery 10 for a motor vehicle in a partially cutaway manner. The battery 10 has a plurality of battery cells 12, which are arranged to provide electrical energy to the electric powertrain of the motor vehicle. In particular, the battery 10 is a traction battery for a motor vehicle. In addition to the plurality of battery cells 12, the battery 10 also has a battery housing 14. The battery housing 14 surrounds a housing interior space 16, in which the plurality of battery cells 12 are accommodated. In this example, the battery housing 14 has a cover 18 and a perforated plate 20, which provides the bottom of the battery housing 14. In the prescribed installation position of the battery 10 in the motor vehicle, the cover 18 delimits the housing interior space 16 upward in the vertical direction z of the vehicle, and the perforated plate 20 delimits the housing interior space 16 downward in the vertical direction z of the vehicle.

[0028] As from Figure 1 As can be seen in the figure, the battery cell 12 is arranged above the perforated plate 20 in the vertical direction z of the vehicle. In particular, the battery cell 12 is supported by the perforated plate 20. To this end, the battery cell 12 can be placed directly or indirectly on the perforated plate 20. In the present example, the bottom of the battery housing 14 is formed by a high-voltage accumulator basin 22 having the perforated plate 20. In the present example, the high-voltage accumulator basin 22 is formed from steel and serves as a thrust field. In the installation position of the battery 10 in the motor vehicle, not only the high-voltage accumulator basin 22 but also the cover 18 are connected to the sill 26 of the motor vehicle via a first threaded connection device 24 in this example. Figure 3 The high pressure accumulator basin 22 with the orifice plate 20 is shown separately in FIG. Figure 3As can be seen particularly well in FIG. 2 , the perforated plate 20 has a plurality of exhaust openings 28. For the sake of clarity, Figure 3 Only some of the ventilation openings 28 are denoted by associated reference numerals. The perforated plate 20 has an associated ventilation opening 28 for each battery cell 12 .

[0029] exist Figure 2 , a partial view of the battery 10 is shown, in which it can be particularly well seen that the corresponding battery cell 12 is arranged above the corresponding matching exhaust opening 28 in the vertical direction z of the vehicle. Here, the battery cell 12 completely covers the matching exhaust opening 28 in the vertical direction z of the vehicle. In particular, the exhaust opening 28 is arranged to cover the gas blow-out opening of the battery cell 12 downward in the vertical direction z of the vehicle. Here, the gas blow-out opening of the battery cell 12 is arranged on the lower side of the battery cell 12. Therefore, the gas, in particular the hot gas, flowing out from the corresponding battery cell 12 via the gas blow-out opening, in particular due to the thermal runaway of the battery cell 12, can be discharged from the battery cell 12 involved via the matching exhaust opening 28. Therefore, the hot gas generated in the battery cell 12 during thermal runaway can be discharged from the housing interior 16 via the exhaust opening 28.

[0030] In order to ensure that the housing interior space 16 is closed watertightly when the battery 10 is operating normally and therefore when any of the battery cells 12 does not have thermal runaway, a sealing layer 30 is provided in this example. In this example, the sealing layer 30 is arranged between the battery cell 12 and the perforated plate 20 and is provided for sealing all exhaust openings 28 watertightly. The sealing layer 30 can be provided by an adhesive or by a plastic component or by foam. The sealing layer 30 is provided for releasing the exhaust opening 28 matched with the battery cell 12 when the battery cell 12 is in thermal runaway. This can be achieved by partially melting the sealing layer 30 and thereby releasing the passage from the battery cell 12 to the exhaust opening 28. Therefore, the watertightness of the housing interior space 16 can be guaranteed when the battery 10 is operating normally, and in addition, when one of the battery cells 12 is in thermal runaway, it can be ensured that the hot gas generated can be discharged from the housing interior space 16 via the matching exhaust opening 28.

[0031] As in Figure 1 and Figure 2As can be seen in , a basin 32 can be arranged below the battery housing 14 in the vertical direction z of the vehicle, which basin serves as bollard protection. The basin 32 can be a replaceable base plate for the battery 10. In the present example, the replaceable base plate has a sandwich structure consisting of a first glass fiber reinforced plastic component 34, a foam 36 and a second glass fiber reinforced plastic component 38. In the present example, the basin 32 is fixed to the high-pressure accumulator basin 22 via at least one second threaded connection device 42 and to the sill 26 via at least one third threaded connection device 44. The at least one second threaded connection device 42 and the at least one third threaded connection device 44 enable non-destructive and reversible replaceability of the basin 32 on the battery housing 14 of the battery 10 and on the sill 26 of the motor vehicle. As shown in Figure 1 and Figure 2 As can be seen particularly well in FIG, the basin 32 together with the perforated plate 20 delimits a buffer volume 46. An impact-absorbing foam 48 can be arranged in the buffer volume 46. The impact-absorbing foam 48 can be adhesively bonded to the perforated plate 20 on the underside of the perforated plate 20 facing away from the battery cells 12. As a result, the impact-absorbing foam 48 is particularly securely fixed in the buffer volume 46. The impact-absorbing foam 48 is a supporting structure for the battery 10 and serves as a sacrificial component in the event of an impact from below.

[0032] The battery 10 described can achieve an improvement in the overall rigidity of the motor vehicle, while improving the repairability in the event of minor damage. In addition, the battery 10 can achieve a weight reduction compared to conventional batteries for corresponding motor vehicles.

[0033] In the battery 10 described, the perforated plate 20 is arranged below the battery cell 12 in the vehicle vertical direction z, and a foam, in the present case an impact-absorbing foam 48, which is integrated in a removable protective component, in the present case a pot 32, is provided below the perforated plate 20. In order to suppress the heat propagation of the battery cell 12 by discharging the generated gases into the impact-absorbing foam 48, it is provided that the housing bottom has the perforated plate 20. The battery cell 12 is thus vented into a buffer volume 46 surrounded by the removable pot 32.

[0034] The battery cell 12 can be bonded to the perforated plate 20 from above. In this case, the exhaust opening 28 is sealed watertightly with an adhesive. Alternatively or additionally, the exhaust opening 28 is sealed with a plastic component. The perforated plate 20 can be made of aluminum or steel and has an exhaust opening 28 below each battery cell 12. The exhaust opening is closed in such a way that the corresponding battery cell 12 can be exhausted. This means that the hot gas of the battery cell 12 can break through the closure. An impact absorbing foam 48 is arranged below the perforated plate 20, into which the battery cell 12 can be exhausted. The impact absorbing foam 48 is used to cushion the impact on the battery 10 from below. The impact absorbing foam 48 is preassembled in a basin 32 that can be removed from the motor vehicle and is bonded to the perforated plate 20 from below. The basin 32 can be made of plastic, in particular glass fiber reinforced plastic and / or light metal.

[0035] If no sealing layer 30 is provided, the housing interior 16 can be sealed at the bottom by means of the pot 32 in order to prevent water from entering the housing interior 16 .

[0036] The sandwich structure of the battery 10, which consists of the housing upper part or cover 18, the battery cells 12 and the perforated plate 20, enables a particularly high overall rigidity of the battery 10. Thus, a functional separation is achieved between the battery housing 14 and the pan 32 which provides underbody protection in conjunction with the impact-absorbing foam 48. The pan 32 together with the impact-absorbing foam 48 assumes the functions of transmission protection and underbody protection.

[0037] In summary, the invention shows how a sandwich high-pressure accumulator bottom with ventilation channels, in the present case ventilation openings 28 , can be provided for cell propagation situations.

[0038] Reference numerals list

[0039] 10. Battery

[0040] 12 Battery Cells

[0041] 14 Battery housing

[0042] 16 Shell internal space

[0043] 18 Cover

[0044] 20-well plate

[0045] 22 Shell bottom

[0046] 24 First threaded connection device

[0047] 26 Sill beam

[0048] 28 Exhaust opening

[0049] 30 Sealing layer

[0050] 32 Pelvis

[0051] 34 The first glass fiber reinforced plastic component

[0052] 36 Bubble

[0053] 38 Second glass fiber reinforced plastic component

[0054] 42 Second threaded connection device

[0055] 44 Third threaded connection device

[0056] 46 Buffer volume

[0057] 48 Impact Absorbing Foam

[0058] z Vertical direction of vehicle

[0059] x Vehicle longitudinal direction

[0060] y Vehicle lateral direction

Claims

1. A battery (10) for a motor vehicle, comprising: A plurality of battery cells (12) and A battery housing (14), the battery housing enclosing a housing interior space (16), the battery cells (12) being accommodated in the housing interior space, and the housing interior space having a perforated plate (20), the battery cells (12) being placed on the perforated plate, the perforated plate (20) having a corresponding exhaust opening (28) for each battery cell (12), the corresponding battery cell (12) being placed on the exhaust opening, and the gas exhausted from the corresponding corresponding battery cell (12) being able to be discharged from the housing interior space (16) via the exhaust opening; in, A gap is provided between the battery cell (12) and the perforated plate (28), the battery cell (12) is surrounded by foam in the housing interior (16), and the foam closes the gap and the exhaust opening (28); and / or Impact absorbing foam (48) is bonded to the side of the perforated plate (20) opposite to the battery cell (12).

2. The battery (10) according to claim 1, characterized in that: The battery cell is directly placed flat on the perforated plate (20).

3. The battery (10) according to claim 1 or 2, characterized in that: The vent opening (28) is sealed by means of a sealing layer (30) which is provided to be penetrated by hot gases flowing out of the battery cell (12) in the event of thermal runaway.

4. The battery (10) according to claim 3, characterized in that The sealing layer (30) has an adhesive layer, via which the battery cell (12) is bonded to the perforated plate (20), and / or the sealing layer (30) has at least one plastic element, which rests on the perforated plate (28).

5. The battery (10) according to one of the preceding claims, characterized in that A pot (32) is arranged on the side of the perforated plate (20) opposite the battery cells (12), which pot, together with the perforated plate (20), surrounds a buffer volume (46) in which an impact-absorbing foam (48) is arranged.

6. The battery (10) according to claim 5, characterized in that The basin (32) is connected to the perforated plate (20) in a sealing manner.

7. The battery (10) according to claim 5 or 6, characterized in that: The pot (32) is reversibly held on the battery housing (14).

8. A motor vehicle having a battery (10) according to one of the preceding claims.

Images