BATTERY ARRANGEMENT AND METHOD FOR DISCHARGING A GAS FROM A BATTERY ARRANGEMENT

Abstract

A battery arrangement having a housing base arrangement and at least one battery unit which is arranged on the housing base arrangement and is arranged above the housing base arrangement with respect to a first direction and which comprises at least one battery cell. The at least one battery cell has a first side having a releasable degassing opening which is releasable for discharging a gas from the at least one battery cell. The housing base arrangement has at least one predetermined breaking point, which is designed, in dependence on a gas escape of a gas from the degassing opening of the at least one battery cell, to release an opening penetrating the housing base arrangement with respect to the first direction, in order to discharge the gas escaping from the degassing opening of the at least one battery cell through the released opening.

Claims

1. A battery arrangement, comprising: a housing base arrangement and at least one battery unit which is arranged on the housing base arrangement and is arranged above the housing base arrangement with respect to a first direction and which comprises at least one battery cell, wherein the at least one battery cell has a first side having a releasable degassing opening which is releasable for discharging a gas from the at least one battery cell, wherein the housing base arrangement has at least one predetermined breaking point, which is designed, in dependence on a gas escape of a gas from the degassing opening of the at least one battery cell, to release an opening penetrating the housing base arrangement with respect to the first direction, in order to discharge the gas escaping from the degassing opening of the at least one battery cell through the released opening.

2. The battery arrangement of claim 1, wherein the battery unit is arranged on the housing base arrangement in such a way that the first side of the at least one battery cell faces toward the housing base arrangement.

3. The battery arrangement of claim 1, wherein the housing base arrangement comprises a housing base which is designed as a cooling base through which a coolant can flow.

4. The battery arrangement of claim 1, wherein the housing base arrangement has a housing base and an electrically insulating layer, in particular a plastic film, which is arranged between the battery unit and the housing base, and/or a thermal interface layer, which is arranged between the battery unit and the housing base, for thermally coupling the housing base and the battery unit.

5. The battery arrangement of claim 1, wherein the predetermined breaking point is formed as a local weakening of the housing base, in particular wherein the local weakening is provided by: a material weakening; and/or a connecting point, in particular a weakened connecting point, at which a first part of the housing base is connected to a second part of the housing base.

6. The battery arrangement of claim 1, wherein the predetermined breaking point is formed as a local weakening of an element of the housing base arrangement which is different from the housing base, in particular as a material weakening of the element which is different from the housing base.

7. The battery arrangement of claim 6, the material weakening is provided by: at least one perforation line, which extends in a straight or curved manner, in particular as an open or as a closed line; and/or a material taper along at least one line which extends straight or curved, in particular open or as a closed line; and/or a hole, corresponding to the size of the opening to be released, in an element of the housing base arrangement, which hole is covered by a further element of the housing base arrangement, when no gas escapes from the at least one battery cell; and/or at least one blind hole, which corresponds to the size of the opening to be released, and/or multiple blind holes extending along at least one line.

8. The battery arrangement of claim 1, wherein the releasable degassing opening of the at least one battery cell adjoins a cavity which provides a gas discharge channel and which is delimited with respect to the first direction by at least one part of the housing base arrangement, in particular at least the housing base and the electrically insulating layer located on the housing base.

9. The battery arrangement of claim 1, wherein the releasable degassing opening of the at least one battery cell is directly adjoining the housing base arrangement, wherein the predetermined breaking point is unambiguously associated with the degassing opening in that the predetermined breaking point is arranged directly below the degassing opening with respect to the first direction.

10. A method for discharging a gas from a battery arrangement having a housing base arrangement and at least one battery unit which is arranged on the housing base arrangement and is arranged above the housing base arrangement with respect to a first direction and which comprises at least one battery cell, wherein the at least one battery cell has a first side having a releasable degassing opening which is released for discharging a gas from the at least one battery cell, wherein the housing base arrangement has at least one predetermined breaking point, which releases, in dependence on a gas escape of a gas from the degassing opening of the at least one battery cell, an opening penetrating the housing base arrangement with respect to the first direction, in order to discharge the gas escaping from the degassing opening of the at least one battery cell through the released opening.

11. The battery arrangement of claim 2, wherein the housing base arrangement comprises a housing base which is designed as a cooling base through which a coolant can flow.

12. The battery arrangement of claim 3, wherein the housing base arrangement has a housing base and an electrically insulating layer, in particular a plastic film, which is arranged between the battery unit and the housing base, and/or a thermal interface layer, which is arranged between the battery unit and the housing base, for thermally coupling the housing base and the battery unit.

13. The battery arrangement of claim 2, wherein the predetermined breaking point is formed as a local weakening of the housing base, in particular wherein the local weakening is provided by: a material weakening; and/or a connecting point, in particular a weakened connecting point, at which a first part of the housing base is connected to a second part of the housing base.

14. The battery arrangement of claim 3, wherein the predetermined breaking point is formed as a local weakening of the housing base, in particular wherein the local weakening is provided by: a material weakening; and/or a connecting point, in particular a weakened connecting point, at which a first part of the housing base is connected to a second part of the housing base.

15. The battery arrangement of claim 4, wherein the predetermined breaking point is formed as a local weakening of the housing base, in particular wherein the local weakening is provided by: a material weakening; and/or a connecting point, in particular a weakened connecting point, at which a first part of the housing base is connected to a second part of the housing base.

16. The battery arrangement of claim 2, wherein the predetermined breaking point is formed as a local weakening of an element of the housing base arrangement which is different from the housing base, in particular as a material weakening of the element which is different from the housing base.

17. The battery arrangement of claim 3, wherein the predetermined breaking point is formed as a local weakening of an element of the housing base arrangement which is different from the housing base, in particular as a material weakening of the element which is different from the housing base.

18. The battery arrangement of claim 4, wherein the predetermined breaking point is formed as a local weakening of an element of the housing base arrangement which is different from the housing base, in particular as a material weakening of the element which is different from the housing base.

19. The battery arrangement of claim 2, wherein the releasable degassing opening of the at least one battery cell is directly adjoining the housing base arrangement, wherein the predetermined breaking point is unambiguously associated with the degassing opening in that the predetermined breaking point is arranged directly below the degassing opening with respect to the first direction.

20. The battery arrangement of claim 3, wherein the releasable degassing opening of the at least one battery cell is directly adjoining the housing base arrangement, wherein the predetermined breaking point is unambiguously associated with the degassing opening in that the predetermined breaking point is arranged directly below the degassing opening with respect to the first direction.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0033] Exemplary embodiments of the invention are described hereinafter. In the figures:

[0034] FIG. 1 shows a schematic cross-sectional illustration of a battery arrangement according to one exemplary embodiment of the invention;

[0035] FIG. 2 shows a schematic illustration of a housing base having a predetermined breaking point for a battery arrangement in a top view according to one exemplary embodiment of the invention;

[0036] FIG. 3 shows a schematic illustration of the housing base for the battery arrangement having a predetermined breaking point in a top view according to a further exemplary embodiment of the invention;

[0037] FIG. 4 shows a schematic illustration of a housing base in a top view having a predetermined breaking point according to another exemplary embodiment of the invention;

[0038] FIG. 5 shows a schematic illustration of the housing base in a top view having a predetermined breaking point for a battery arrangement according to another exemplary embodiment of the invention; and

[0039] FIG. 6 shows a schematic cross-sectional illustration of a battery arrangement according to another exemplary embodiment of the invention.

DETAILED DESCRIPTION

[0040] The exemplary embodiments explained hereinafter are preferred embodiments of the invention. In the exemplary embodiments, the described components of the embodiments each represent individual features of the invention to be considered independently of one another, which each also refine the invention independently of one another and are thus also to be considered to be part of the invention individually or in a combination other than that shown. Therefore, the disclosure is also intended to comprise combinations of the features of the embodiments other than those shown. Furthermore, the described embodiments can also be supplemented by further ones of the already described features of the invention.

[0041] In the figures, same reference numerals respectively designate elements that have the same function.

[0042] FIG. 1 shows a schematic illustration of a battery arrangement 10 according to one exemplary embodiment of the invention. The battery arrangement 10 has a housing base arrangement 12 and a battery unit 14 which is arranged on the housing base 12 and comprises at least one battery cell 16, wherein the battery unit 14 represents the battery cell 16 in this example. In this example, a prismatic battery cell 16 is illustrated, but this can also be formed in any other way. The battery cell 16 can be, for example, a lithium-ion cell. The battery cell 16 has a first side 16a, which defines an underside 16a of the battery cell 16 in this example. On this first side 16a, the battery cell 16 also has a releasable degassing opening 18, which can be formed using a bursting membrane, for example. In case of a thermal event, the gas produced in the cell 16 can be deliberately discharged from this releasable degassing opening 18. The gas escaping from the cell 16 is illustrated by the arrow 20 in FIG. 1 as an example. The battery cell 16 is also arranged in a battery housing 22, of which only the housing base 24 is shown as an example in FIG. 1. In the present example, the battery cell 16 or the battery unit 14 is generally not arranged directly on the housing base 24, but an electrical insulation layer in the form of a plastic film 26 is initially also arranged on the housing base 24 and between this plastic film 26 and the battery cell 16 or the battery unit 14, a thermal interface layer 28 is also arranged, which can be designed, for example, as a gap filler or gap pad. These two layers, namely the plastic film 26 and the thermal interface layer 28, are also part of the housing base arrangement 12.

[0043] In order to prevent the gas 20 escaping from the cell 16 from causing the battery housing 22 to explode in an uncontrolled manner, the housing base arrangement 12 advantageously has a predetermined breaking point 30, which in the present example is provided by an opening or a hole 31 in the housing base 24. This predetermined breaking point 30 thus represents a failure area which is designed to release an opening 32 penetrating the housing base arrangement 12 in the illustrated z direction in case of degassing of the cell 16, so that the gas 20 escaping from the cell 16 can be discharged through this opening 32, which is shown in FIG. 1 is shown in the still closed state, in particular from the battery housing 22. As a result, several major advantages can be achieved at the same time: On the one hand, controlled gas discharge can be made possible, which prevents the battery housing 22 from exploding in an uncontrolled manner By designing this gas discharge option not as a separate valve or component, but as a predetermined breaking point 30 in the housing base arrangement 12 itself, it is also possible to save enormous costs on the one hand and on the other hand to make this discharge option significantly lower in height. In particular, this does not increase the installation space required for the housing base arrangement 12 in the z direction. This makes it possible for such a discharge option to be integrated into the bottom of the battery housing 22 in the first place. The housing base 24 is moreover preferably designed as a cooling base. This can, for example, also have cooling channels (not shown here), through which a coolant can flow. The integration of the predetermined breaking point 30 in the housing base arrangement 12 advantageously allows the gas 20 escaping from the battery cell 16 to be deliberately directed away from a passenger compartment of the motor vehicle in which the battery arrangement 10 is used. The battery arrangement 10 is preferably arranged in a motor vehicle in such a way that the Z axis shown here is aligned in the direction of a vehicle vertical axis. The gas can thus be deliberately introduced into a harmless area, for example between the housing base 24 and an underride protection of the motor vehicle. From there, the gas 20 can be deliberately discharged, for example in the direction of a vehicle rear.

[0044] In the present example, the predetermined breaking point 30 is shown directly below the releasable degassing opening 18 of the cell 16 in relation to the y direction shown. However, this predetermined breaking point can also be arranged offset in the y direction with respect to the degassing opening 18. If gas 20 escapes from the cell 16, it is first introduced into a degassing channel or gas discharge channel 34, which is embodied by a cavity adjacent to the degassing opening 18. For example, multiple cells 16 or battery units 14 can also be arranged next to one another in the y direction, so that this cavity 34 is arranged as a common gas discharge channel 34 below a respective degassing opening 18 of such a cell 16. For this entire degassing channel 34, for example, only one predetermined breaking point 30 or only a few predetermined breaking points 30 can be provided in the housing base arrangement 12, which are in particular significantly fewer in number than the degassing openings 18 coupled or capable of being coupled to the degassing channel 34. In this case, the gas discharge channel 34 can thus extend over multiple cells in the y direction, and the film 26 can also be made continuous in the y direction, while the hole 31 is locally restricted in the y direction, preferably to only a small area. For example, the hole 31 can be made circular. As a result, the housing base arrangement 12 does not lose its stability.

[0045] In this example, the predetermined breaking point 30 in the housing base arrangement 12 is provided by the hole in the housing base 24 and in particular also in the thermal interface layer 28 for providing the cavity 34 for the gas discharge channel 34 being provided there. The housing base arrangement 12 thus only still consists of the plastic film 26 in the area of the predetermined breaking point 30. However, numerous other design options for providing a predetermined breaking point 30 are also conceivable. In particular, a hole does not necessarily have to be provided in the housing base 24 at this point. This can also only be weakened at this point. There are various options for providing such a local weakening, which are explained in more detail hereinafter.

[0046] For this purpose, FIG. 2 shows a schematic illustration of the housing base 24 for a battery arrangement 10, as described with reference to FIG. 1, for example, in a top view, wherein the housing base 24 can be formed as described above except for the differences described hereinafter. In this example, the housing base 24 has a predetermined breaking point 30 which is formed as a material taper 36 along a line, in particular a closed line in this example. In this example, the predetermined breaking point 30 is therefore provided as a closed score track 36 or groove. It can also be provided in some form of notch or embossing. In this case, the housing base 24 is not completely broken through in the z direction, but is made thinner than the other areas in the z direction due to the design described.

[0047] FIG. 3 shows a schematic representation of another example of a housing base 24, again in a top view. In this example, the predetermined breaking point is provided as a circular and closed perforation line 38 which has multiple individual perforation holes 40 arranged in a circle. These can therefore completely penetrate the housing base in the z direction. Alternatively, it is also conceivable that this perforation line 38 is not provided by continuous perforation holes 40 but by blind holes 42. These then correspondingly do not penetrate the housing base 24 completely in the z direction. In both cases, this allows a perforated or at least partially perforated line 38 to be provided as a predetermined breaking point 30.

[0048] FIG. 4 shows another example of a housing base 24 having a predetermined breaking point 30. In this example, this is also formed as a material weakening, which, however, is not provided along a closed line, but rather along multiple non-closed lines. The material weakening can again be provided along these lines 44 in the form of perforation holes 40 or blind holes 42 or again as a continuous groove 36.

[0049] FIG. 5 shows a further example of a possible embodiment of a housing base 24 having a predetermined breaking point 30. In this example, the housing base 24 is again shown in a top view of the z direction. In addition, the housing base 24 in this example has a first part 24a and a second part 24b, which are connected to one another along a joining area 46. A joint connection is denoted by 48 in the present case. Such a joint connection can be provided, for example, by welding, roll bonding, adhesive bonding, or the like. In this example, this joint connection 48 is weakened or not implemented at all in an area 50, which accordingly then provides the predetermined breaking point 30. A joining area 46 can thus advantageously also be used to provide a predetermined breaking point 30.

[0050] The above-described possible embodiments of the predetermined breaking point 30 as a material weakening in the housing base 24 can additionally or alternatively also be implemented analogously in the other layers of the housing base arrangement 12 in order to provide such a predetermined breaking point 30. However, it is advantageous if such a predetermined breaking point does not provide a through opening that completely penetrates the housing base arrangement 12 in the z direction during normal operation. In the case of the provision of perforation holes 40, for example, it is correspondingly advantageous if, for example, another of the layers of the housing base arrangement 12 covers these continuous perforation holes 40 accordingly.

[0051] FIG. 6 shows a cross section of a battery arrangement 10 according to an exemplary embodiment of the invention. This battery arrangement can also be designed, for example, as described for FIG. 1, except for the differences described hereinafter. In this example, no gas discharge channel 34 is provided as described for FIG. 1. Instead, in this example, the thermal interface layer 28 also contacts the first side 16a of the cell 16 in the area of the degassing opening 18. In other words, the releasable degassing opening 18 of the cell 16 is covered in the normal operating state by the thermal interface layer 28, i.e., for example, the gap pad or the gap filler material. In this example, the predetermined breaking point 30 is again formed as an opening 31 in the housing base 24. As a result, the housing base arrangement 12 is weakened in the area of the degassing opening 18 in comparison to the other areas, i.e., in areas in which no such predetermined breaking point 30 is provided. In this case, this opening 31 is located at least directly below the degassing opening 18 in relation to the z direction and can therefore not be arranged offset in relation to it in the y direction, as can be the case in FIG. 1. In the case of a multiple cells 16 having respective degassing openings 18, one associated predetermined breaking point 30 can be provided per degassing opening 18 here. It would also be conceivable, for example, to form the hole 31 in the housing base 24 in an elongated manner, so that one predetermined breaking point 30 is provided for multiple degassing openings 18 at the same time. However, this makes the housing base 24 significantly less stable overall.

[0052] This represents a particularly advantageous embodiment, since in this example there is no need to keep ready a recessed area for the provision of a degassing channel which, for example, is not wetted using gap filler material. This enables a thermal interface layer 28 to be introduced over a large area, onto which the cells 16 or battery units 14 can simply be placed. Since both the plastic film 26 and this thermal interface layer 28 are relatively thin, a predetermined breaking point 30 can also be provided in this way in an advantageous manner.

[0053] Overall, the examples show how a novel concept for a bottom venting battery tray can be provided by the invention. The invention or its embodiments use the idea of deliberately incorporating failure areas in one or more components. The overpressure regulation of the battery tray then does not take place via separately installed vents. Instead, the battery ventilation is integrated directly into the base, in particular the cooling base, of the battery tray. For this purpose, the cooling base consisting of aluminum sheet can be deliberately provided with predetermined breaking points. If an excessive pressure increase occurs, the cooling base will fail at the predetermined breaking point and relieve the gas pressure. As a result, no additional component in the sense of a relief valve is advantageously required. The component and the associated assembly process can be saved completely. The ventilation can be carried out over a significantly larger area and thus contributes to occupant protection. The ventilation can take place in one area and the gas discharge can take place in a favorable direction, namely downwards. The implementation is also concept-neutral. As with a beverage can, in which a drinking opening is made solely by the material properties of the aluminum and is provided by a targeted pre-notch, the contents can be stored in a defined manner, but can also be broken open in a defined manner. In the present example as well, such a predetermined breaking point can be provided in numerous variations by targeted notching of an active ingredient.