Battery system for a motor vehicle that is at least partially electrically powered

Abstract

Battery assembly (1) comprising a frame structure (2) and a plurality of battery modules (11) screwed to the frame structure (2), each battery module (11) having a module housing (3) for enclosing battery cells (21). The module housing (3) comprises a top plate (23) with screw receptacles (4) on the top plate (23). The screw receptacles (4) comprise two base screw receptacles (5) and two auxiliary screw receptacles (6). The auxiliary screw receptacle (6) comprises a through-hole (16) for the screw (44) with a cross-section in the form of an elongated hole (26). The base screw receptacle (5) comprises a bushing section (15) circumferentially enclosing the screw (44) and a predetermined breaking structure (25) formed on the bushing section (15).

Description

[0001] The present invention relates to a battery device for an at least partially electrically powered motor vehicle having a frame structure and a plurality of battery modules screwed to the frame structure. The battery modules each comprise a module housing, which includes a base structure and at least one head plate arranged transversely to the base structure. Screw receptacles for receiving a respective screw are arranged on the head plate, wherein the screw extends through the screw receptacle and is screwed into a threaded structure of the frame structure.

[0002] Such battery systems enable stable and reliable installation of the battery modules in the vehicle. However, it has been shown that if an accident-related load is introduced into the battery system, the battery modules can shift relative to each other. These relative movements can lead to housing deformation and further damage to the module housings. Furthermore, a crash can cause the head plates to detach from the module housing.

[0003] DE 10 2019 131 598 B3 shows a battery housing for a motor vehicle with battery modules and a frame structure. It addresses the possibility that the frame structure can move relative to the battery modules in an accident, potentially causing damage to the battery modules. It is proposed to mount the battery modules using a floating bearing and a fixed bearing. The floating bearing is designed as an elongated hole, allowing for a crash-related displacement of the battery module in a predefined direction.

[0004] DE 10 2017 117 726 A1 discloses a housing device for energy storage systems for attachment to a vehicle chassis. Further features that can be implemented in energy storage systems are known from the publications US 2019 / 0 363 323 A1, US 6 230 834 B1, US 3 053 336 A, and CN 2 13 401 419 U.

[0005] In contrast, the object of the present invention is to provide an improved battery device. In particular, the previously discussed accident-related load effects on the battery device are to be avoided in a structurally simple and reliable manner.

[0006] This object is achieved by a battery device having the features of claim 1. Preferred developments of the invention are the subject of the subclaims. Further advantages and features of the present invention will become apparent from the general description and the description of the exemplary embodiment.

[0007] The battery device according to the invention is provided for an at least partially electrically powered motor vehicle, in particular a passenger car. The battery device comprises at least one frame structure and a plurality of battery modules screwed to the frame structure. The battery modules each comprise a module housing for enclosing battery cells. The module housing comprises a base structure and at least one head plate arranged transversely to the base structure. Screw receptacles for receiving at least one screw are arranged on the head plate. The screw runs through the screw receptacle and is in particular screwed into a threaded structure of the frame structure. The screw receptacles arranged on each head plate comprise at least two base screw receptacles and at least two additional screw receptacles.In a first alternative, the additional screw receptacles each comprise a (circumferentially closed) through-opening for the arranged screw. The through-opening has a cross-section in the form of an elongated hole (so-called elongated hole cross-section). This allows the module to preferably move relative to the screw arranged in the elongated hole if the battery modules are displaced due to a crash. The base screw receptacles each comprise a socket section that surrounds the screw in the circumferential direction and at least one predetermined breaking structure formed on the socket section and running in the longitudinal direction of the screw received therein. This allows the socket section to open circumferentially in a targeted manner if the battery modules are displaced due to a crash relative to the screw received therein. This allows the battery module to preferably move relative to the screw received therein.

[0008] The battery device according to the invention offers many advantages. A significant advantage is provided by the base screw receptacles and the additional screw receptacles, with their respective capabilities for allowing a defined displacement of the battery modules in the event of a crash. This allows the battery modules to move in a targeted manner relative to the screws and / or pivot about a rotation axis running parallel to the longitudinal axes of the screws in the event of an accident-related load. The base screw receptacles, with their predetermined breaking structures, prevent, for example, the occurrence of unfavorable tensile loads that could lead to the head plates becoming detached from the rest of the module housing. The additional screw receptacles, with their elongated holes, ensure, for example, that the accident-related relative movement does not lead to a critical deformation of the module housing.

[0009] In an advantageous embodiment, the head plate has two opposite end sections. The end sections are located opposite one another, in particular transversely to the longitudinal direction of the screw or transversely to the vehicle's vertical axis. In particular, the end sections are located opposite one another in the vehicle's longitudinal direction or in the vehicle's transverse direction. Preferably, at least one (only one) of the at least two additional screw receptacles is arranged on each end section of the head plate. Preferably, the at least two base screw receptacles are arranged between the additional screw receptacles. In particular, only two base screw receptacles are arranged between the additional screw receptacles. This enables a particularly reliable connection of the battery modules to the frame structure. At the same time, with such a structural connection of the end plates, the advantages of the invention described here can be particularly well utilized.

[0010] In particular, at least one base screw receptacle and at least one additional screw receptacle are arranged on both sides of a central axis of the head plates running in the longitudinal direction of the screw. In particular, the additional screw receptacles are arranged further outward than the base screw receptacles. In particular, the additional screw receptacles are arranged in the region of the side edges of the head plate running in the direction of the vehicle's vertical axis.

[0011] It is preferred and advantageous for the battery modules to be arranged at least partially side by side, in particular along the vehicle's longitudinal axis. The adjacent battery modules are preferably each bolted to a common longitudinal member of the frame structure by means of screw receptacles, each with at least one head plate. Such an arrangement applies in particular to those head plates of the module housings that are located at the same end of the module housing.

[0012] Preferably, the head plates of the adjacent battery modules are arranged parallel and, in particular, aligned with one another. In particular, the head plates of the adjacent battery modules are arranged parallel and, in particular, aligned along the vehicle's longitudinal axis. With such a series of battery modules, the invention presented here can counteract adverse loads on the module housing particularly reliably.

[0013] It is possible and advantageous for the additional screw receptacle to be designed as a tab protruding from the head plate. In particular, the tab is flat or plate-shaped. The tab can also be referred to as a plate-like projection.

[0014] In particular, the tab rests on the frame structure for support. In particular, the bushing section also rests on the frame structure for support.

[0015] In particular, the bushing section and an adjacent auxiliary screw receptacle have a common bearing surface with which they rest on the frame structure. In particular, the bearing surfaces of the auxiliary screw receptacles and the base screw receptacles, which are assigned to a common head plate, are arranged in a common plane. In particular, at least a portion of the vertical load or load extending in the direction of the vehicle's vertical axis rests on the auxiliary screw receptacle and / or on the base screw receptacle.

[0016] The tab is preferably attached in sections to a (radial) outer side of the socket section. In particular, the tab is integrally connected to the socket section. This particularly applies to the socket section that is arranged adjacent to the tab on the common head plate. In particular, the tab is attached in sections to the head plate. In particular, the tab is preferably integrally connected to the head plate.

[0017] It is possible and advantageous for the additional screw receptacle for securing the module housing to the frame structure to be formed before and during the fastening of the module housing to the frame structure using the base screw receptacle. In other words, the additional screw receptacle secures the module housing before and while the screw is inserted through the respective base screw receptacle and screwed into the frame structure. The additional screw receptacle can therefore be referred to as a so-called assembly fixing screw connection.

[0018] In particular, the bushing section has a length running in the longitudinal direction of the screw received therein. In particular, the additional screw receptacle has a length running in the longitudinal direction of the screw received therein. It is preferred and advantageous for the length of the bushing section to be many times greater than the length of the additional screw receptacle. In particular, the length of the bushing section is at least five times, or at least six times, or at least eight times, or at least ten times the length of the additional screw receptacle. In particular, the screw received in the bushing section is also many times greater than the length of the screw received in the additional screw receptacle.

[0019] In an advantageous development, the bushing section extends in the longitudinal direction of the screw received therein over at least half the height of the head plate. The height of the head plate corresponds to a dimension of the head plate that extends in the longitudinal direction of the screw received in the bushing section or in the direction of the vehicle's vertical axis. In particular, the length of the bushing section is at least 50%, at least 65%, or at least 75% of the height of the head plate. The length of the bushing section can also be at least 85% or at least 95% of the height of the head plate. The bushing section can also extend over the entire height of the head plate.

[0020] The bushing section is preferably (essentially and for example at least 90% or 95%) firmly and in particular integrally connected to the head plate over its (entire) length running in the longitudinal direction of the screw.

[0021] In an advantageous embodiment, the predetermined breaking structure is provided in that the bushing section is slotted at least partially and preferably continuously in the longitudinal direction of the screw accommodated therein. A slotted bushing section is understood in particular to mean that the slot extends in the radial direction from an inner side to an outer side of the bushing section. In particular, the bushing section completely encloses the screw in the circumferential direction with the exception of the area where it is continuously slotted. Such a slot enables reliable and targeted failure of the predetermined breaking structure. The slot allows the bushing section to open in the event of an accident and then move almost independently of the screw accommodated therein.

[0022] In a similarly advantageous embodiment, the predetermined breaking structure is designed as a groove running in the longitudinal direction of the screw accommodated therein and incorporated into the bushing section. This also enables targeted and reliable failure of the predetermined breaking structure in the event of a crash.

[0023] In particular, the base screw receptacles and the additional screw receptacles are formed integrally with the associated head plate. In particular, the head plate is firmly connected to a supporting structure of the module housing and, for example, to a side wall and / or a base structure and / or another module housing component. In particular, the head plate is welded to the rest of the module housing.

[0024] The battery device is, in particular, a traction battery. The battery device is preferably designed as a high-voltage battery. The motor vehicle is, in particular, a hybrid vehicle and / or a battery-electric vehicle (BEV).

[0025] The frame structure is in particular firmly connected to a body of the vehicle and / or is an integral part of the body. The frame structure comprises in particular at least one longitudinal member and / or at least one cross member and / or at least one floor plate structure. In particular, the battery modules are screwed to the at least one longitudinal member and / or cross member of the frame structure. In particular, the threaded structure is formed directly on the frame structure. It is also possible for the threaded structure to be provided by a nut or the like resting on the frame structure. In the intended assembled state, a head of the screw rests in particular on the respective screw receptacle.

[0026] The module housing can comprise at least one cover structure and / or side walls. The module housing can comprise at least two opposing head plates. In particular, the head plate is connected to side walls running transversely to the head plate. In particular, the head plate and in particular also the side walls extend in the direction of the vehicle's vertical axis. In particular, the side walls extend in the direction of the vehicle's vertical axis and the vehicle's transverse axis. In particular, the head plates extend in the direction of the vehicle's vertical axis and the vehicle's longitudinal axis.

[0027] It is possible and advantageous for the additional screw receptacle, and in particular the tab, to also be equipped with a predetermined breaking structure. In particular, the predetermined breaking structure is designed in the same way as described for the base screw receptacle. The through-hole of the additional screw receptacle, in particular, has a closed perimeter. The through-hole can also be referred to as a slotted through-hole.

[0028] In particular, the bushing sections each have a (circumferentially closed) through-opening (so-called bushing through-opening) for the screw arranged therein. The bushing through-opening preferably has a circular cross-section. In particular, the bushing section is hollow-cylindrical. It is possible and advantageous for the bushing through-opening to also have a cross-section in the shape of an elongated hole. In particular, the elongated hole is designed in the same way as described for the additional screw receptacle.

[0029] In particular, the additional screw receptacles and the base screw receptacles of each head plate are arranged parallel with respect to the longitudinal direction of their screw. In particular, the screw receptacles are arranged parallel with respect to the longitudinal direction of their screws. In particular, the screws are arranged parallel to the vehicle's vertical axis with respect to their longitudinal direction. In particular, the battery modules are lined up such that the additional screw receptacles and the base screw receptacles of the head plates are arranged parallel with respect to the longitudinal direction of the screws.

[0030] Further advantages and features of the present invention will become apparent from the embodiments which are explained below with reference to the accompanying figures.

[0031] The figures show: Fig. 1 a purely schematic representation of a battery device according to the invention in a sectional plan view; Fig. 2 an enlarged section of the Fig. 1; and Fig. 3 a detailed view of the battery device of the Fig. 1 in a perspective view.

[0032] The Fig. Figure 1 shows a section of a battery device according to the invention, which here is a traction battery for an electric vehicle and is designed as a high-voltage battery. The battery device 1 according to the invention is described below with reference to Fig. 1 to 3 are presented as examples.

[0033] The battery device 1 comprises a plurality of battery modules 11, each with a plurality of battery cells 21, of which only one battery cell 21 is shown here as an example for clarity. To securely enclose the battery cells 21, each battery module 11 is equipped with a module housing 3 having a base structure 13 and side walls 43 arranged transversely thereto. At one or two opposite ends, the module housings 3 are each equipped with a head plate 23 arranged transversely to the base structure 13.

[0034] Parallel to the base structure 13, a cover structure 33 can be provided, as shown for example in the Fig. 3 can be seen.

[0035] The battery device 1 comprises a frame structure 2, of which a longitudinal member 12 can be seen here. Screw receptacles 4 are formed on the head plates 23, through each of which a screw 44 extends. The screws 44 are screwed into a threaded structure 54 of the longitudinal member 12 (not visible here). Fig. For clarity, the screws 44 are not shown in Figure 3. However, the longitudinal axes of the screws 44 are shown in dashed lines.

[0036] In the Fig. 1 clearly shows that the battery modules 11 are arranged side by side, for example, along the vehicle's longitudinal axis. The adjacent battery modules 11 are each bolted to the common longitudinal member 12 with a head plate 23. The head plates 23 are arranged parallel and aligned with each other.

[0037] The screw receptacles 4, each arranged on a head plate 23, are provided by two base screw receptacles 5 and two additional screw receptacles 6. The additional screw receptacles 6 are arranged here at opposite end sections 53 of the head plate 23. The two base screw receptacles 5 are arranged between the additional screw receptacles 6. Both the base screw receptacle 5 and the additional screw receptacles 6 are formed integrally with the head plate 23.

[0038] The base screw receptacle 5 comprises a bushing section 15, which circumferentially surrounds the screw 44. The bushing section 15 is integrally connected to the head plate 23 over its entire length. The head plates 23 are welded to a load-bearing structure of the module housing 3.

[0039] In the event of a crash, tensile stresses can act outward on the head plates 23. Such tensile stress can lead to the welded head plates 23 becoming detached from the remaining module housing 3. To counteract such stresses, the base screw receptacles 5 are each equipped with a predetermined breaking structure 25.

[0040] The predetermined breaking structure 25 runs here in the longitudinal direction of the received screw 44 through the bushing section 15. As in the Fig. 2 and Fig.3, the predetermined breaking structure 25 is provided by the bushing section 15 being continuously slotted in the longitudinal direction. Alternatively or in addition to such a slot, the predetermined breaking structure 25 can also be provided, for example, by a groove machined into the bushing section 15. These predetermined breaking structures 25 act as force limiters and relieve the load on the module housing 3 in the event of a crash. This allows the battery modules 11 to move in the direction of the vehicle's longitudinal axis and pivot about the vehicle's vertical axis without critical tensile stresses acting on the head plates 23.

[0041] The additional screw receptacles 6 serve here to fix the module housing 3 to the frame structure 2 before and during the installation of the screw 44 for the base screw receptacles 5. For this purpose, the additional screw receptacles 6 are designed here as tabs 36 that protrude from the head plate 23. The tabs 36 and also the bushing sections 15 rest here in a supporting manner on the longitudinal member 12. The tabs are attached in sections to a radial outer side of the adjacent bushing section 15. Furthermore, the tab 36 is attached in sections to the head plate 23.

[0042] The additional screw receptacles 6 each have a circumferentially closed through-opening 16 for a screw 44. The through-opening 16 has the cross-section of an elongated hole 26. In a side impact, the battery modules 11 shift and / or pivot relative to one another. This relative movement can lead to adverse housing deformations. The elongated holes 26 in the additional screw receptacles 6 allow the battery modules 11 to move relative to one another in a crash without adverse deformations occurring on the module housing 3. List of reference symbols: 1 battery device 2 Frame structure 3 module housings 4 screw receptacles 5 base screw holder 6 additional screw holders 11 Battery module 12 longitudinal members 13 Soil structure 15 socket section 16 passage opening 21 battery cells 23 Headstock 25 Predetermined breaking structure 26 slot 33 Lid structure 36 tab 43 Side wall 44 Screw 53 final section 54 Thread structure

Claims

[1] Battery device (1) for an at least partially electrically powered motor vehicle with a frame structure (2) and with a plurality of battery modules (11) screwed to the frame structure (2), wherein the battery modules (11) each have a module housing (3) for enclosing battery cells (21) and wherein the module housing (3) comprises a base structure (13) and at least one head plate (23) arranged transversely to the base structure (13), wherein screw receptacles (4) for receiving a respective screw (44) are arranged on the head plate (23), wherein the screw (44) extends through the screw receptacle (4) and is screwed into a threaded structure (54) of the frame structure (2), characterized by , that the screw receptacles (4) arranged on a respective head plate (23) comprise at least two base screw receptacles (5) and at least two additional screw receptacles (6) and that the additional screw receptacles (6) each comprise a through-opening (16) for the screw (44) and that the through-opening (16) has a cross-section in the form of an elongated hole (26) so that the battery module (11) can move relative to the screw (44) if the battery modules (11) are displaced due to a crash and that the base screw receptacles (5) each have a bushing section (15) surrounding the screw (44) in the circumferential direction and each have a predetermined breaking structure (25) formed on the bushing section (15) and running in the longitudinal direction of the screw (44), so that the bushing section (15) opens circumferentially in a targeted manner in the event of a crash-related displacement of the battery modules (11) and the battery module (11) can move relative to the screw (44). [2] Battery device (1) according to the preceding claim, wherein the head plate (23) has two opposite end sections (53) and wherein at least one of the at least two additional screw receptacles (6) is arranged on each end section (53) of the head plate (23) and wherein the at least two base screw receptacles (5) are arranged between the additional screw receptacles (6). [3] Battery device (1) according to one of the preceding claims, wherein the battery modules (11) are at least partially arranged next to one another and wherein the adjacent battery modules (11) are each screwed to a common longitudinal member (12) of the frame structure (2) by means of the screw receptacles (4) with at least one head plate (23). [4] Battery device (1) according to the preceding claim, wherein the head plates (23) of the adjacent battery modules (11) are arranged parallel and aligned with one another. [5] Battery device (1) according to one of the preceding claims, wherein the additional screw receptacle (6) is designed as a tab (36) projecting on the head plate (23) and wherein the tab (26) rests on the frame structure (2) in a supporting manner. [6] Battery device (1) according to the preceding claim, wherein the tab (36) is attached in sections to an outer side of the socket section (15). [7] Battery device (1) according to one of the preceding claims, wherein the additional screw receptacle (6) is designed to fix the module housing (3) to the frame structure (2) before and during the fastening of the module housing (3) to the frame structure (2) by means of the base screw receptacle (5). [8] Battery device (1) according to one of the preceding claims, wherein the socket section (15) has a length running in the longitudinal direction of the screw (44) and wherein the additional screw receptacle (6) has a length running in the longitudinal direction of the screw (44) and wherein the length of the socket section (15) is many times greater than the length of the additional screw receptacle (6). [9] Battery device (1) according to one of the preceding claims, wherein the socket section (15) extends in the longitudinal direction of the screw (44) over at least half of a height of the head plate (23) extending in the longitudinal direction of the screw (44). [10] Battery device (1) according to one of the preceding claims, wherein the socket section (15) is firmly and preferably integrally connected to the head plate (23) over its entire length extending in the longitudinal direction of the screw (44). [11] Battery device (1) according to one of the preceding claims, wherein the predetermined breaking structure (25) is provided in that the socket section (15) is slotted at least in sections and preferably continuously in the longitudinal direction of the screw (44) or wherein the predetermined breaking structure (25) is designed as a groove running in the longitudinal direction of the screw (44) and incorporated into the socket section (15).

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