Securing structure
The fastening structure with screws and axially unfixed bolts addresses the inefficiencies of traditional screw-based mounting, achieving quicker and cost-effective high-voltage battery installation with improved tolerance compensation.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- MAGNA STEYR FAHRZEUGTECHNIK AG & CO KG
- Filing Date
- 2025-12-19
- Publication Date
- 2026-06-25
Smart Images

Figure EP2025088456_25062026_PF_FP_ABST
Abstract
Description
[0001] Mounting structure
[0002] Field of invention
[0003] The present invention relates to a fastening structure for fastening a high-voltage battery in a motor vehicle and a method for mounting a high-voltage battery in a motor vehicle using such a fastening structure.
[0004] State of the art
[0005] It is known that high-voltage batteries are used in motor vehicles to provide electrical energy for a vehicle's drive motor, particularly in electric or hybrid vehicles. High-voltage batteries occupy a relatively large volume to achieve the highest possible storage capacity and are therefore installed in a space-saving manner, for example, in the area of the vehicle floor.
[0006] It is particularly well known to position a high-voltage battery beneath the floor panel of a motor vehicle and to attach it to the side sills, i.e., the longitudinal members of the motor vehicle. During assembly, the traction batteries are bolted to the sills from below. For this purpose, the nuts for the bolts are typically located within the sill.
[0007] US Patent 10,603,998 B2 discloses a battery mounting structure for securing a battery beneath a vehicle floor panel. The battery mounting structure comprises a battery pack that is located beneath
[0008] 2024P00096 WO 19.12.2025 BZ is attached to a floor panel of a vehicle cabin; a vehicle body frame element to which a horizontally extending end section of the floor panel is connected; and a sealing element that is elastic and closes a gap between the battery pack and the vehicle body frame element.
[0009] Summary of the invention
[0010] One object of the invention is to provide a mounting structure for securing a high-voltage battery in a motor vehicle, enabling quick and cost-effective installation and reliable securing of the high-voltage battery. A further object of the invention is to provide a quick and cost-effective method for mounting a high-voltage battery in a motor vehicle using a reliable mounting structure.
[0011] The problem is solved by a fastening structure for securing a high-voltage battery in a motor vehicle, comprising a battery housing of the high-voltage battery and at least one sill of the motor vehicle, wherein the battery housing is fastened to the sill of the motor vehicle by means of several screw connections, wherein the battery housing is additionally fastened to the sill by means of several unbolted, i.e. axially unfixed, bolts.
[0012] According to the invention, a high-voltage battery is thus attached to a sill, preferably to both side sills of a motor vehicle, not exclusively by means of screws, but at some positions, instead of screws, with bolts that are not screwed in. The bolts are not axially fixed by means of nuts or similar fasteners, but are axially fixed, preferably in the Z-direction of the
[0013] 2024P00096 WO 19.12.2025 BZ Motor vehicle, essentially freely movable, i.e. axially floating, so that axial movement between battery housing and sill is possible in the area of the bolts.
[0014] Typically, traction batteries are secured in a vehicle's underbody with numerous individual screws. This requires a significant amount of fasteners and increases installation time. However, for reliable high-voltage battery mounting, fewer vertical fixings are sufficient, meaning fewer mounting points are needed in the vehicle's Z-direction than in the X and Y directions. By reducing the number of screw points and using bolts, especially centering bolts, the installation effort for a high-voltage battery can be reduced while ensuring reliable battery mounting.
[0015] Further developments of the invention are specified in the dependent claims, the description and the accompanying drawings.
[0016] Preferably, the bolts are firmly joined to the battery housing or to the sill and are arranged on the other component, i.e., on the sill or on the battery housing, section by section, i.e., in an axial section of the respective bolt, in a receiving element without threads, in particular a sleeve.
[0017] The screw connections are each arranged section by section in a threaded receiving element, in particular a nut, and screwed through this receiving element. The receiving element is preferably located inside the sill.
[0018] 2024P00096 WO 19.12.2025 BZ Preferably, the screw connections and / or bolts are each sectionally mounted in sleeves such that they can compensate for tolerances in a plane normal to the sleeve, i.e., normal to the bolts and / or screws. Tolerance compensation can thus preferably take place in a horizontal plane, i.e., in the X and Y directions of the motor vehicle.
[0019] Preferably, the bolts and screws are arranged alternately along the sill, with the screws being particularly preferably arranged in a line and the bolts being arranged alternately between the fastening points in the same line. Preferably, at least one such line of alternating screws and bolts is formed on each of the two sills, on both sides of the battery housing.
[0020] According to a preferred embodiment, the bolts are welded to the battery housing and are particularly preferably aligned upwards in the Z-direction, i.e., they protrude upwards.
[0021] The sill is preferably made of aluminum. In this embodiment, the bolts are also preferably made of aluminum. Preferably, the threadless mounting elements for the bolts, in particular the sleeves, are made of steel. Particularly preferably, several sleeves are welded onto a common steel strip. The steel strip can be arranged between the sill and the mounting elements.
[0022] According to another preferred embodiment, the bolts are welded to the sill and are preferably aligned downwards in the Z-direction, i.e., they protrude downwards.
[0023] 2024P00096 WO 19.12.2025 BZ Preferably the sill, preferably in this embodiment with downward-protruding bolts, is made of steel and / or the bolts are made of steel.
[0024] The mounting elements without threads for the bolts, especially the sleeves, can be made of aluminium.
[0025] An inventive method for mounting a high-voltage battery in a motor vehicle using a fastening structure as described above can provide that the high-voltage battery is brought to the underside of the sill and arranged such that the bolts in the receiving elements are arranged without threads, in particular in the sleeves, wherein the battery housing is then fastened by means of the screw connections, namely screwed at the positions of the screw connections.
[0026] Brief description of the drawings
[0027] The invention is described below by way of example with reference to the drawings.
[0028] Fig. 1 is a sectional view of a fastening structure according to the invention in a first embodiment in the area of a screw connection.
[0029] Fig. 2 is a sectional view of a fastening structure according to the invention in a first embodiment in the area of a bolt.
[0030] 2024P00096 WO 19.12.2025 BZ Fig. 3 is a schematic view of an arrangement of
[0031] Screws and bolts in a fastening structure according to the invention.
[0032] Fig. 4 is a sectional view of a fastening structure according to the invention in a second embodiment in the area of a screw connection.
[0033] Fig. 5 is a sectional view of a fastening structure according to the invention in a second embodiment in the area of a bolt.
[0034] Detailed description of the invention
[0035] Figure 1 shows a fastening structure according to the invention in a first embodiment in the area of a screw connection 3. The battery housing 1 can be made of aluminum and attached to a sill 2, which is also made of aluminum.
[0036] The drive battery 1 can be screwed into place from below using screws 3. Typically, a large number of screws are used for fastening.
[0037] The nuts, i.e., threaded mounting elements 6, can be located in the sill 2. Sleeves, i.e., threadless mounting elements 5, for example, weld-in sleeves made of aluminum, are welded into the battery housing 1. The screws 3 are inserted through these sleeves, and they also allow for tolerance compensation in the horizontal direction.
[0038] 2024P00096 WO 19.12.2025 BZ The sleeves 5 protrude upwards, towards the sill 2, slightly beyond the battery mounting flange of the battery housing 1. As a result, the battery housing 1 does not rest directly on the sill 2, but the sleeve 5 also allows for improved tolerance compensation in the vertical direction, i.e., in the axial direction of the sleeve 5, relative to the sill 2.
[0039] Fig. 2 is a sectional view of the fastening structure according to the invention as shown in Fig. 1, but in the area of a bolt 4, which can be a centering bolt made of aluminium.
[0040] As schematically shown in Fig. 3, preferably every second fastening point, or every nth fastening point, can use a bolt 4 instead of a screw 3 for fastening. In particular, a welded-in aluminum bushing with a centering pin as its upper section can be used as the bolt 4, which is inserted into a threadless receiving element 5 and is not screwed in (Fig. 2). The bushing of the bolt 2—similar to the sleeve 5 in Fig. 1—projects beyond the battery housing 1, thus allowing for tolerance compensation in the vertical direction relative to the sill 2.
[0041] The threadless receiving element 5 is preferably made of steel and is preferably welded onto a steel strip 7, which in turn is preferably inserted into a groove in the sill profile of the sill 2.
[0042] Force transmission can only occur in the horizontal direction. In the axial direction, the bolt 4 is not fixed in the threadless receiving element 5, i.e., it is not secured.
[0043] 2024P00096 WO 19.12.2025 BZ Fig. 3 is a schematic view of an arrangement of screws 3 and bolts 4 in a fastening structure according to the invention. The fastening points of a drive battery are thus shown.
[0044] Typically, traction batteries or high-voltage batteries are mounted in a vehicle underbody using numerous individual screws 3, meaning all mounting points are designed as screws 3. However, this requires a large amount of fastening material and increased installation time.
[0045] In an installation according to the invention, preferably every second fastening point is a bolt 4 which is inserted into a threadless receiving element 5 during assembly but is not screwed in. This saves assembly time and fastening material.
[0046] If, for example, a drive battery were screwed to itself with n fastening elements, for example n=30, then, for example, n / 2 or less than n / 2, for example between n / 4 and n / 2 of the fastening points, can be replaced by bolts 4, for example 12 bolts.
[0047] The bolts 4 are pre-assembled on the battery side and require no additional assembly effort.
[0048] Fig. 4 is a sectional view of a fastening structure according to the invention in a second embodiment in the area of a screw connection 3.
[0049] The illustration shows the installation of an aluminum battery housing 1 on a steel sill 2.
[0050] Typically, even with a steel sill, the drive batteries are screwed in from below during assembly.
[0051] 2024P00096 WO 19.12.2025 BZ In the embodiment according to Fig. 4, the nuts or receiving elements with thread 6, for example weld nuts, are arranged in the sill 2, and sleeves, in particular weld-in sleeves made of aluminium, are welded into the battery housing 1 as receiving elements without thread 5, through which the screws 3 are inserted and which also provide for tolerance compensation.
[0052] Fig. 5 shows this fastening structure in the area of a bolt 4. Steel centering bolts are used for fastening.
[0053] For example, every second fastening point consists of a weld stud 4 made of steel with a centering tip, and is preferably welded into a sill 2 made of steel.
[0054] During assembly, the centering tip is inserted into a sleeve, in particular a weld-in sleeve made of aluminum, as a threadless receiving element 5 in the battery frame of the battery housing 1, but is not screwed in. The sleeve is made of aluminum and is already an integral part of the battery housing 1.
[0055] Power transmission can only occur in a horizontal direction here.
[0056] 2024P00096 WO 19.12.2025 BZ Reference List
[0057] Battery housing
[0058] Sill
[0059] screw connection
[0060] bolt
[0061] Mounting element without thread
[0062] Mounting element with threaded steel strip
[0063] 2024P00096 WO 19.12.2025 BZ
Claims
Patent claims 1. Fastening structure for fastening a high-voltage battery in a motor vehicle, comprising a battery housing (1) of the high-voltage battery and at least one sill (2) of the motor vehicle, wherein the battery housing (1) is fastened to the sill (2) of the motor vehicle by means of several screw connections (3), characterized in that the battery housing (1) is additionally fastened to the sill (2) by means of several unbolted, i.e. axially unfixed, bolts (4).
2. Fastening structure according to claim 1, characterized in that the bolts (4) are firmly joined to the battery housing (1) or to the sill (2) and are arranged section by section in a receiving element without thread (5), in particular a sleeve, on the other component, i.e. on the sill (2) or on the battery housing (1).
3. Fastening structure according to claim 2, characterized in that the screw connections (3) are each arranged section by section in a receiving element with thread (6), in particular a screw nut, and are screwed through this receiving element with thread (6), wherein the receiving element with thread (6) is preferably arranged inside the sill (2).
4. Fastening structure according to at least one of the preceding claims, 2024P00096 WO 19.12.2025 BZ characterized by the fact that the screw connections (3) and / or the bolts (4) are each sectionally mounted in sleeves in such a way that they can perform a tolerance compensation in a plane normal to the sleeve.
5. Fastening structure according to at least one of the preceding claims, characterized in that the bolts (4) are arranged alternately with the screw connections (3) along the sill (2), wherein preferably the screw connections (3) are arranged in a line and the bolts (4) are arranged alternately between the fastening points in the same line.
6. Fastening structure according to at least one of the preceding claims, characterized in that the bolts (4) are welded to the battery housing (1) and are preferably oriented upwards in the Z direction.
7. Fastening structure according to claim 6, characterized in that the sill (2) is made of aluminium and / or that the bolts (4) are made of aluminium.
8. Fastening structure according to claim 2 and according to claim 6 or 7, characterized in that the receiving elements are without threads (5) for the bolts (4), in particular 2024P00096 WO 19.12.2025 BZ the sleeves are made of steel, preferably with several sleeves being welded onto a common steel strip (7).
9. Fastening structure according to at least one of claims 1 to 5, characterized in that the bolts (4) are welded to the sill (2) and are preferably aligned downwards in the Z direction.
10. Fastening structure according to claim 9, characterized in that the sill (2) is made of steel and / or that the bolts (4) are made of steel.
11. Fastening structure according to claim 2 and according to claim 9 or 10, characterized in that the receiving elements without threads (5) for the bolts (4), in particular the sleeves, are made of aluminium.
12. Method for mounting a high-voltage battery in a motor vehicle by means of a fastening structure according to at least one of the preceding claims, characterized in that the battery housing (1) of the high-voltage battery is brought to the underside of the sill (2) and arranged such that the bolts (4) are arranged in the receiving elements without threads (5), in particular in the sleeves, wherein the battery housing (1) is then fastened by means of the screw connections (3), namely screwed in place. 2024P00096 WO 19.12.2025 BZ