SUPPORTING STRUCTURE FOR A NUMBER OF BATTERY MODULES AND BATTERY MODULE ARRANGEMENT

Description

[0001] The invention relates to a support structure for a number of battery modules, comprising: a plurality of support elements, which support elements are arranged at a distance from one another and form a number of compartments between them, which compartments are each intended to accommodate a battery module, according to claim 1.

[0002] The invention also relates to a battery module arrangement comprising a support structure according to the invention and a number of battery modules accommodated in compartments of the support structure, according to claim 15. Battery modules, in particular lithium-based ones, are increasingly used today for the (temporary) storage of electrical energy and for supplying devices with electrical energy. For this purpose, a large number of battery modules are usually interconnected and housed in special shelving systems in a common enclosure, e.g., in the manner of a (shipping) container.

[0003] During operation, such battery modules generate a considerable amount of waste heat, so temperature control (especially cooling) is often required, particularly fluid-based cooling, in which a cooling fluid flows through the individual battery cells internally. The disadvantage here is that a corresponding fluid cooling system must be provided in addition to the aforementioned rack system, making the entire design complex and expensive and requiring more space. This consumes additional material. To ensure assembly and accessibility for maintenance, special design measures are necessary, which also have a negative impact on installation space and system costs.

[0004] WO 2019 / 169080 A1 discloses a battery tray for an electric vehicle comprising a floor structure having an upper surface configured to be connected to battery modules. The battery tray also includes a plurality of cooling elements extending integrally along portions of the floor structure and configured to dissipate heat from the battery modules arranged on the upper surface of the floor structure.

[0005] US 2013 / 017428 A1 describes an energy storage device comprising a plurality of battery trays arranged substantially parallel to one another to form at least one row. The battery trays are connected to a first and a second channel. Air is drawn into the first channel via an air inlet, and air is discharged from the second channel to the outside of the energy storage device via an air outlet.

[0006] There is a need for a support system or a support structure for battery modules as well as a corresponding battery module arrangement that enables temperature control of the battery modules without suffering from the above-mentioned disadvantages in terms of installation space requirements, material consumption, costs, effort and accessibility, and that is scalable depending on the requirements.

[0007] This object is achieved according to the invention by a support structure having the features of claim 1 and by a battery module arrangement having the features of claim 15.

[0008] Advantageous developments of the invention are defined in the respective subclaims.

[0009] According to the invention, a support structure for a number of battery modules comprises a plurality of support elements, which support elements are arranged spaced apart from one another and form a number of compartments between them, each compartment being intended to accommodate a battery module; wherein at least a number of the support elements (hereinafter also referred to as "fluid-conducting support elements") are designed as fluid line elements or comprise fluid line elements, which fluid line elements extend into the respective region of the compartments and via which fluid line elements a temperature control fluid for the battery modules can be supplied to the region of the compartments and discharged from there again, wherein the fluid-conducting support elements are releasably clamped together in pairs with at least one sealing element, preferably adhesively bonded, soldered, or welded. In this way, support structures of any size can be constructed depending on requirements.

[0010] Advantageously, this primarily concerns vertical support elements that form a kind of shelving structure and accommodate horizontal support elements like shelves or the like between them, on which the battery modules can be arranged between the vertical support elements. These vertical and horizontal support elements define (especially cuboid-shaped) compartments or receptacles for the battery modules, as is known from conventional shelving systems or "racks."

[0011] The invention now involves at least some of the support elements, whereby fundamentally no distinction is made between vertical and horizontal support elements, assuming a dual function – namely, both as a static support component and as a fluid-carrying line component. This thus involves a functional integration of the support function of the battery module rack and the fluid guidance / distribution of a cooling medium for the thermal management of the battery modules in one system.

[0012] According to the invention, a battery module arrangement comprising the support structure according to the invention and a number of battery modules which are accommodated in compartments of the support structure is characterized in that the battery modules (or at least some of the battery modules) have an internal temperature control circuit and are fluidically connected to the fluid-conducting support elements.

[0013] This results in the advantageous functional integration already mentioned.

[0014] In other words, it is proposed to build a Battery Cooling Pipe (BCP) which, in addition to the function of fluid guidance for a temperature control medium, also functions as a support structure for the battery modules.

[0015] The BCP is preferably designed such that at least a portion of the support structure, i.e., a number of the support elements forming the support structure, is designed in a closed, pipeline-like manner to fulfill the fluid-conducting function. The connection to the remaining support structure, i.e., the remaining support elements, can be detachably established by a screw connection or, preferably, permanently established by a forming connection, such as rivets, and most preferably, firmly bonded by gluing, soldering, or welding.

[0016] The fluid-carrying support structure (i.e. the fluid-carrying support elements) can be used to distribute a mass flow of the temperature control medium to the consumers (i.e. the battery modules), for example by creating appropriate branches by specifically attaching necklines or the like.

[0017] A corresponding variant of the support structure according to the invention comprises support elements that are fluid-conducting and designed with multiple hollow chambers. Preferably, two hollow chambers are used to provide the supply and return lines of the temperature control medium in a single support element. A particularly advantageous three-chamber system can, for example, include a supply line, a return line, and an additional chamber for extinguishing agent and / or purge gas. The extinguishing agent can be released in the event of a malfunction.

[0018] Optionally, additional chambers can be provided for routing cables or for communication as well as for flue gas ducting and used accordingly.

[0019] To connect the fluid-carrying support elements (FTE for short), they are releasably clamped together with the interposition of at least one sealing element (e.g. O-ring), preferably glued, soldered or welded

[0020] In a further variant, the FTEs can be connected and interconnected by node elements, which are preferably manufactured by primary forming, e.g., as cast parts. These node elements can provide additional functions, such as vent valves, sampling, measuring elements / sensors, inlet and outlet points, or fixing points.

[0021] Depending on the requirements, the connection of the FTE with the node elements can be designed as a non-detachable material connection or detachable connection in order to take into account the desired assembly capability.

[0022] The FTEs can also be used to exchange heat with the environment. Cooling fins or similar structures may be present for this purpose.

[0023] Preferably, the aforementioned branches on the FTE are designed in such a way that fluid contact is created directly during installation (preferably by inserting) of the battery modules into the support structure or into the relevant compartments. The connection can be secured by holding the battery modules in position within the support structure, which is already routinely done. Separate additional securing devices are therefore not required.

[0024] A further variant of the invention provides that the (rack) compartments are equipped with base plates and integrated base plate cooling, in particular by means of the temperature control fluid, to which the batteries can be mounted directly in a heat-conducting manner. The base plate cooling can be directly connected, preferably without an additional sealing element, to a supply and discharge of the temperature control fluid to the FTE. Direct heat conduction between the base plates and the battery modules can be achieved using a thermal paste or mechanical bracing.

[0025] Another design variant involves equipping the (rack compartment) floor panels with heat pipes, which preferably extend into the FTE and dissipate heat there. Additional fluid contact can be eliminated in this way.

[0026] If (additional) vertical cooling plates are connected to the FTE, the battery modules can (also) be cooled laterally after they have been thermally connected to the cooling plates (e.g. by means of thermal paste and / or mechanical bracing).

[0027] This variant can be particularly advantageous if the battery modules have an internal immersion cooling circuit to transport the generated heat to an external surface from which it can be more easily dissipated. This saves installation space and achieves a more homogeneous temperature distribution within the system.

[0028] The following embodiments have proven particularly advantageous: A first development of the support structure according to the invention provides that at least a number of the support elements themselves are circumferentially closed and designed as fluid-conducting elements. This achieves particularly extensive functional integration.

[0029] A second development of the support structure according to the invention provides that the fluid-conducting support elements are connected to a remaining, non-fluid-conducting support structure either detachably, in particular by screwing, or permanently, in particular by riveting or by a material bond, e.g., by soldering or welding. In this way, a stable, expandable support structure is achieved.

[0030] A third development of the support structure according to the invention provides that at least a number of the fluid-conducting support elements have at least two fluidically separated chambers or fluid line elements. In this way, both a fluid supply and a return line can be formed within the support elements, further reducing the number of required components.

[0031] Another development of the support structure according to the invention provides that at least a number of the fluid-conducting support elements have at least three fluidically separated chambers or fluid-conducting elements. This allows additional functions to be integrated into the FTE.

[0032] For example, as already mentioned, it can be provided that at least a number of the fluid-conducting support elements have additional chambers for guiding cables or for communication or for flue gas conduction.

[0033] Yet another development of the support structure according to the invention provides that the fluid-conducting support elements are connected and interconnected by node elements, which node elements are preferably manufactured by primary forming. This has already been mentioned in detail above.

[0034] The node elements can preferably have additional functions, such as vent valves, sampling, measuring elements / sensors, inlet and outlet points, or fixing points, as already mentioned. This can achieve functional added value.

[0035] With appropriate further development, a respective connection of the fluid-conducting support elements with the node elements can be designed to be non-detachable, preferably materially bonded, or detachable in order to ensure the greatest possible modularity.

[0036] In a further development of the support structure according to the invention, it can also be provided that fluidic connection structures for the battery modules are present in the region of the compartments. These connection structures are preferably designed to be flexible, most preferably in the form of corrugated hose sections or bellows that are accessible in an insertion direction when the battery modules are inserted into the compartments, in order to establish a fluidic connection between the battery modules and the fluid-conducting support elements when the battery modules are inserted. This allows a type of "plug-and-play" connection to be created between the battery modules and the support structure, which is particularly easy to implement. A corresponding electrical connection for the battery modules and / or a data connection (e.g., to the BMS - battery management system) can be used accordingly.

[0037] A corresponding development of the battery module arrangement according to the invention includes that the fluidic connection structures for the battery modules in the region of the compartments are aligned in the insertion direction with at least partially complementary, in particular rigid, connection structures of the battery modules in order to establish a fluidic connection between battery modules and fluid-conducting support elements quasi automatically when the battery modules are inserted, wherein preferably the complementary connection structures of the battery modules engage in the connection structures of the support structure, or vice versa, preferably with the interposition of at least one sealing element, which sealing element is preferably arranged on the connection structures of the battery modules.

[0038] In a further development of the support structure according to the invention, it can also be provided that it has a (position) securing device for the battery modules in the area of the compartments, which securing device is also designed to secure the fluidic connection. This also achieves improved functional integration.

[0039] In a further development of the support structure according to the invention, it can further be provided that a base plate is provided in the area of at least some compartments, which base plate is intended for thermally conductive contact with at least one battery module and which base plate is fluidly connected to at least one fluid-conducting support element. The advantages of this configuration have already been mentioned above.

[0040] In a further development of the support structure according to the invention, it can further be provided that a base plate is provided in the area of at least some compartments, which base plate is intended for thermally conductive contact with at least one battery module and which base plate is connected to at least one fluid-conducting support element via at least one heat pipe. The advantages of this configuration have already been mentioned above.

[0041] Finally, in a further development of the support structure according to the invention, it can be provided that at least one lateral cooling plate is provided in the area of at least some compartments, which cooling plate is intended for thermally conductive contact with at least one battery module. The advantages of this configuration have also been mentioned above.

[0042] Further features and advantages of the invention will become apparent from the exemplary embodiments described below with reference to the drawings. Figure 1 schematically shows a battery module arrangement according to the invention; Figure 2 schematically shows a battery module arrangement according to the invention with a support structure according to the invention; Figure 3 shows a detail of a battery module arrangement or support structure according to the invention; Figure 4 shows a further detail of a battery module arrangement or support structure according to the invention; and Figure 5 shows yet another detail of a battery module arrangement or support structure according to the invention.

[0043] The same reference symbols denote the same or at least the same acting elements in all figures.

[0044] In Figure 11 shows a generic battery module arrangement comprising a plurality of battery modules 2 stacked in an arrangement of (horizontal) rows and (vertical) columns. Typically, the battery modules 2 are located within a suitable housing 3, which Figure 1 is only symbolically shown in dashed lines.

[0045] According to Figure 1The battery modules 2 are each equipped with an internal temperature control circuit for a temperature control fluid, which temperature control circuit is symbolically represented by reference numeral 4. A conveying means 5 is provided in fluidic connection with the internal temperature control circuits 4 in order to supply the temperature control fluid (temperature control medium) to the individual battery modules 2 and then (after heat transfer) to discharge it from there again. Reference numeral 6 denotes a tank or storage means for the temperature control fluid. The conveying means 5 and the storage means 6 form an external temperature control circuit for the temperature control fluid, which external temperature control circuit is not shown again in the other figures for reasons of clarity. The external temperature control circuit does not necessarily have to be arranged outside the housing 3.

[0046] Figure 2shows a somewhat more detailed representation of the battery module arrangement 1 or a comparable arrangement in which the battery modules 2 are arranged within a support structure 7 in the manner of a rack or shelf. Such a support structure 7 is also fundamentally present in the battery module arrangement 1 according to Figure 1 available, but not shown there for reasons of clarity.

[0047] How to Figure 2The support structure 7 comprises a series of vertical support elements 7a (posts), which are connected to one another at least in part by horizontal support elements 7b, in order to create the said rack or shelf structure. In this way, the vertical support elements 7a and the horizontal support elements 7b define cuboid-shaped receptacles or compartments 7c for inserting or inserting the battery modules 2, as shown. The support structure 7 is not limited to the number and / or geometric arrangement of the battery modules 2 as shown in the Figure 1 and 2 The design shown is limited in terms of shape and / or size.

[0048] How to do this in particular Figure 2 at least the two front vertical support elements 7a function not only as structural elements, but also as line elements (FTE) for the tempering fluid (compare Figure 1). For this purpose, for example, the front left support element 7a has a connection 8 for introducing the temperature control fluid, while for example the front right support element 7a has a connection 9 for discharging the temperature control fluid. For this purpose, the front left support element 7a can itself be designed as a fluid line element, i.e., circumferentially closed in the manner of a tube, or it can comprise an additional fluid line element inside. It preferably functions as a distribution element, from which the temperature control fluid is supplied to the individual battery modules 2 (in Figure 2 also referred to as B1, B2, B3, ...). For this purpose, the design in Figure 2 Fluid-conducting connecting elements 10a, e.g. in the form of corrugated hose sections, are provided between the front left support element 7a and the individual battery modules 2, which are preferably connected to the respective temperature control circuits 4 (compare Figure 1) of the battery modules 2 are in fluidic connection.

[0049] The front right support element 7a is preferably designed accordingly and serves to collect and drain the temperature control fluid from the individual battery modules 2. For this purpose, fluid-conducting connecting elements 10b, e.g. in the form of corrugated hose sections, are provided between the front right support element 7a and the individual battery modules 2, which are preferably also connected to the respective temperature control circuits 4 (cf. Figure 1 ) of the battery modules are in fluidic connection.

[0050] Not all vertical support elements 7a need to be designed as fluid-conducting support elements. According to the design in Figure 2 For example, only the two front vertical support elements 7a are designed as fluid-conducting support elements. The two rear vertical support elements 7a, of which Figure 2For illustration purposes only one can be seen, they do not have to be fluid-conducting but can be simple support posts.

[0051] In Figure 2 A base plate 11 is shown as an example between the battery modules B2 and B3; corresponding base plates 11 can also be provided between the other battery modules 2. With a corresponding heat-conducting connection between the base plate 11 and the adjacent battery modules B2 and B3 (for example, using heat-conducting paste), additional temperature control of the battery modules can be achieved. For this purpose, the base plate 11 can also be connected in a fluid-conducting manner to the temperature control circuit of the battery module arrangement 1, which in Figure 2is not explicitly shown. Alternatively or additionally, it is also possible to connect the base plate 11 to the adjacent battery modules B2 and / or B3 in a heat-conducting manner via heat pipes or the like in order to enable heat dissipation. This is also shown in Figure 2 not explicitly shown.

[0052] Reference numeral 12 denotes an exemplary node element, which can be used for the (detachable) connection of individual, shorter sections of the vertical support elements 7a. Preferably, such node elements 12 are produced by primary forming, for example, in a casting process, and comprise additional functional elements, such as the Figure 2 the sensor shown as an example at reference number 13, which can be - without limitation - a temperature sensor.

[0053] Figure 3 shows a partial horizontal section through a similar battery module arrangement 1 as shown in the Figure 2 The essential difference is that the vertical support element 7a in this case has two (hollow) chambers 7aa, 7ab, one of which (left) 7aa serves to drain heated temperature control fluid, while the other (right) 7ab is intended for supplying fresh temperature control fluid. In this way, one and the same support element 7a can be used for both supplying and draining temperature control fluid.

[0054] To prevent thermal short circuits as much as possible, the cross-section of element 7a can be designed to minimize the heat transfer area between the flow and return lines. Additionally or alternatively, a thermally insulating element (not shown) can be inserted between the chambers 7aa, 7ab.

[0055] Furthermore, it is also possible to insert a liner (preferably made of plastic) into the support element 7a (not shown) or to manufacture the support element 7a itself from a thermally insulating material. The support element 7a is preferably an extruded plastic profile, most preferably a pultrusion profile with optionally inserted (foam) cores to increase the area moment of inertia and improve thermal insulation.

[0056] The invention is by no means limited to support elements 7a with one or two (hollow) chambers; of course, additional chambers can be provided, for example, to guide cables and / or to convey extinguishing agents or similar substances. The extinguishing agent can also be stored under pressure in the profile (support element 7a) in order to be released via a suitable device, such as a rupture disc, in the event of a fire.

[0057] Likewise, here and in all other embodiments, the horizontal support elements 7b can also function as conduit elements for the tempering fluid, although this is not shown in the figures.

[0058] In Figure 4 A partial vertical section through the support structure 7 is shown. A horizontal support element 7b is visible, which is integrally connected (glued or welded) to a vertical support element 7a at reference numeral 14. The connection can also be detachable (cf. Figure 5 ). The support element 7a is in turn designed as a conduit element for a tempering fluid, which tempering fluid is introduced into the support element 7a at the neckline 15a and is guided in the support element 7a, for example up to the further neckline 15b, from where it reaches a battery module not shown here (compare, for example, reference numeral 10a in Figure 2 ).

[0059] In addition, Figure 4 (dashed) a lateral cooling plate 16, which is preferably brought into heat-conducting contact with a battery module (not shown here) accommodated in the support structure 7, in order to achieve additional temperature control of the battery module, in particular using thermal paste. The lateral cooling plate 16 can be connected in a fluid-conducting manner to the temperature control circuit, ie to the FTE 7a. Additionally or alternatively - analogous to the base plate 11 according to Figure 2 - the use of heat pipes or similar devices should be considered. This is Figure 4 Not shown for reasons of clarity. Of course, corresponding cooling plates 16 can be used on both sides of the supporting structure 7.

[0060] Finally, Figure 5 a similar sectional view as the Figure 3Here, too, the vertical support element 7a is equipped with two chambers 7aa, 7ab, each of which is intended for conducting the temperature control fluid, in this case for supplying fresh temperature control fluid. On each of the chambers 7aa, 7ab, in the area of a respective neck 15a, 15b, a flexible connecting part 17 in the manner of a corrugated hose section with a widened free end is arranged, which connecting part 17 protrudes in the direction of an associated receptacle (compartment) 7c for a battery module 2 and forms a corresponding connecting structure. On the respective battery module 2 or B1, B2, a partially complementary connecting structure in the form of a rigid pipe section 18 is provided, which has a sealing means 19, for example an O-ring, at its free end and is fluidly connected to the internal temperature control circuit (compare reference numeral 4 in Figure 1) of the associated battery module 2. If the battery modules 2 or B1, B2 are now inserted in the direction of the arrows P1, P2 into the associated receptacles or compartments 7c, the relative dimensions of the battery modules 2 or B1, B2 on the one hand and the compartments 7c on the other hand are preferably selected such that the said connection structures along the dotted lines in Figure 5 so that when the battery modules 2 or B1, B2 are inserted, a fluid connection is automatically established between the support element 7a on the one hand and the respective battery module 2 or B1, B2 (i.e. the internal temperature control circuit). For the discharge of the temperature control fluid from the battery modules 2, there are preferably corresponding connection structures, which are shown in the Figure 5 but are not explicitly shown.

[0061] Reference numeral 20 shows, purely schematically, a stop and securing device for the respective battery module 2 or B1, B2, which device ensures that the respective battery module 2 or B1, B2 is securely held in its receptacle (the compartment 7c), thereby simultaneously securing the fluid-conducting connection in the area of the aforementioned connection structures. Furthermore, it is impossible for the battery modules 2 or B1, B2 to be inadvertently inserted too deeply according to the arrows P1, P2, which could otherwise lead to damage, especially to the connection parts 17. Such a securing device can, in principle, be used in all embodiments of the present invention. It is not limited to the embodiment according to Figure 5 limited.

Claims

1. Support structure (7) for a number of battery modules (2), having: a plurality of support elements (7a, 7b), which support elements (7a, 7b) are arranged spaced apart from one another and between them form a number of compartments (7c), which compartments (7c) are intended to each receive a battery module (2); wherein at least a number of support elements (7a) are configured as fluid-conducting elements or comprise fluid-conducting elements, which fluid-conducting elements extend into the respective area of the compartments (7c) and via which fluid-conducting elements a temperature-controlling fluid for the battery modules (2) can be fed into the area of the compartments (7c) and discharged again from there; characterized in that the fluid-conducting support elements (7a) are connected to one another detachably in pairs by at least one sealing element, preferably material-bonded, soldered or welded.

2. Support structure (7) according to claim 1, wherein at least a number of the support elements (7a) are themselves closed around the periphery and are configured as fluid-conducting elements.

3. Support structure (7) according to claim 1 or claim 2, wherein the fluid-conducting support elements (7a) are connected to a remaining, non-fluid-conducting support structure (7) in a detachable manner, in particular by screws, or in a non-detachable manner, in particular by rivets or by material bonding, e.g. by soldering or welding.

4. Support structure (7) according to any one of claims 1 to 3, wherein at least a number of fluid-conducting support elements (7a) have at least two fluidically separated chambers (7aa, 7ab) or fluid-conducting elements.

5. Support structure (7) according to any one of claims 1 to 4, wherein at least a number of the fluid-conducting support elements (7a) have at least three fluidically separated chambers (7aa, 7ab) or fluid-conducting elements.

6. Support structure (7) according to any one of claims 1 to 5, wherein at least a number of the fluid-conducting support elements (7a) have additional chambers for guiding cables or for communication or for conducting flue gas.

7. Support structure (7) according to any one of claims 1 to 6, wherein the fluid-conducting support elements (7a) are connected and interconnected by node elements (12), which node elements (12) are preferably produced by original forms.

8. Support structure (7) according to claim 7, wherein the node elements (12) have additional functions, such as venting valves, sampling, measuring elements / sensors (13), feed and discharge points or fixing points.

9. Support structure (7) according to claim 7 or 8, wherein a respective connection of the fluid-conducting support elements (7a) to the node elements (12) is configured to be non-detachable, preferably material-bonded, or detachable.

10. Support structure (7) according to any one of claims 1 to 9, wherein fluidic connecting structures (17) for the battery modules (2) are provided in the area of the compartments, which connecting structures (17) are preferably configured to be flexible, most preferably in the form of corrugated hose sections or bellows, which are accessible in an insertion direction (P1, P2) when the battery modules (2) are inserted into the compartments (7c) in order to establish a fluidic connection between the battery modules (2) and fluid-conducting support elements (7a) when the battery modules (2) are inserted.

11. Support structure (7) according to claim 10, with a securing apparatus (20) for the battery modules (2) in the area of the compartments (7c), which securing apparatus (20) is also configured to secure the fluidic connection.

12. Support structure (7) according to any one of claims 1 to 11, wherein in the area of at least some compartments (7c) there is a base plate (11) respectively, which base plate (11) is intended for the thermally conductive contacting of a battery module (2) and which base plate (11) is fluidically connected to at least one fluid-conducting support element.

13. Support structure (7) according to any one of claims 1 to 12, wherein a base plate (11) is provided in the area of at least some compartments (7c), which base plate (11) is intended to contact a battery module (2) in a thermally-conductive manner and which base plate (11) is connected to at least one fluid-conducting support element (7a) via at least one heat pipe.

14. Support structure (7) according to any one of claims 1 to 13, wherein in the region of at least some compartments (7c) at least one lateral cooling plate (16) is provided, which cooling plate (16) is intended to contact a battery module (2) in a thermally-conducting manner.

15. Battery module assembly (1), comprising the support structure (7) according to any one of the preceding claims and a number of battery modules (2), which are received in compartments (7c) of the support structure (7), which battery modules (2) have an internal temperature-control circuit (4) and are fluidically connected to the fluid-conducting support elements (7a).

16. Battery module assembly (1) according to claim 15 with a support structure (7) according to claim 11, wherein the fluidic connecting structures (17) for the battery modules (2) in the area of the compartments (7c) are aligned in the insertion direction (P1, P2) with at least partially complementary, in particular rigid connecting structures (18) of the battery modules (2), in order to establish a fluidic connection between the battery modules (2) and fluid-conducting support elements (7a) when the battery modules (2) are inserted, wherein preferably the complementary connecting structures (18) of the battery modules (2) engage in the connecting structures (17) of the support structure (7), or vice versa, preferably with at least one sealing element (19) arranged in between, which sealing element (19) is preferably arranged on the connecting structures (18) of the battery modules (2).