High-voltage battery for an electric vehicle

Abstract

High-voltage battery (9) for an electrically powered vehicle, comprising a battery housing (13) in which at least one battery cell module (21) is arranged, the module comprising a cell stack with a plurality of battery cells (23) stacked one behind the other in a stacking direction, wherein at least one power transmission segment (25) is arranged in the cell stack as a component separate from the battery cells (23), and wherein the power transmission segment (25) is integrated in a crash load path (Ly, Lx) in a crash event, via which the crash force (FS) can be transmitted to a side of the vehicle facing away from the crash, characterized in that the stacking direction of the cell stack is aligned in the longitudinal direction (x) of the vehicle, so that the power transmission segment (25) forms a cross member segment, and that the cross member segment (25) is integrated in a transverse load path (Ly) in a side crash event.via which the side crash force (FS) can be transferred to a side of the vehicle facing away from the crash, that at least two battery cell modules (21) are arranged next to each other in the transverse direction (y) of the vehicle in the battery housing (13), and that the cross member segments (25) of the two battery cell modules (21) are aligned transversely to each other in the transverse direction (y) of the vehicle, forming a cross member (35) which is integrated into the lateral load path (Ly) in the event of a side crash.

Description

[0001] The invention relates to a high-voltage battery for an electrically powered vehicle according to the preamble of claim 1 and to an electrically powered vehicle according to claim 13.

[0002] In an electrically powered, two-track vehicle, a high-voltage battery can be inserted from underneath the vehicle into a battery mounting compartment that is open at the bottom. The battery mounting compartment can be defined vertically by the vehicle floor, which limits the vehicle interior, and laterally by side longitudinal body members.

[0003] A typical high-voltage battery has a battery housing in which at least one battery cell module with a cell stack is arranged. This stack consists of a large number of battery cells. The battery cells are stacked one behind the other in a stacking direction oriented longitudinally along the vehicle. The stacking direction can also run transversely along the vehicle, providing support in a frontal crash.

[0004] In common practice, the high-voltage battery, as a crash-sensitive component, must be protected from mechanical damage, especially in side-impact or ground contact collisions. Against this background, the prior art involves arranging the battery cell modules, which are built from the individual battery cells, within a rigid battery housing. In a side-impact or ground contact collision, the battery housing acts as a load-bearing structure, transferring a side-impact force from the longitudinal body member facing the crash to the longitudinal body member facing away from the crash, or transferring a ground contact force into the body structure via the rigid battery housing, thereby bridging the largely force-free, crash-sensitive battery cells.Furthermore, in the prior art, the high-voltage battery can be covered downwards by a solid floor mounting plate, which protects the battery housing of the high-voltage battery from mechanical damage caused by ground impacts.

[0005] The above safety precautions for side impact and ground contact are associated with a high component cost, a high manufacturing cost and a high installation space cost, which reduces the installation space remaining for the battery cells and thus the battery performance.

[0006] A battery housing for a vehicle is known from DE 10 2016 223 220 A1. A battery arrangement for a motor vehicle with a crash protection element is known from DE 10 2018 112 377 A1. A vehicle battery with at least one cross brace is known from DE 10 2016 009 930 A1.

[0007] The object of the invention is to provide a high-voltage battery and an electrically powered vehicle in which the high-voltage battery can be protected from mechanical damage in the event of a side crash and / or ground contact with reduced component effort, reduced installation space requirement and / or reduced manufacturing effort compared to the prior art.

[0008] The problem is solved by the features of claim 1 or claim 13. Preferred embodiments of the invention are disclosed in the dependent claims.

[0009] The invention relates to a high-voltage battery for an electrically powered vehicle, comprising a battery housing in which at least one battery cell module is arranged. The battery cell module has a cell stack with a plurality of battery cells stacked one behind the other in a stacking direction. The stacking direction can be oriented in the longitudinal direction or in the transverse direction of the vehicle. According to the characterizing part of claim 1, at least one force transmission segment is arranged in the cell stack as a component separate from the battery cells. In the event of a crash, the force transmission segment is integrated into a crash load path via which the crash force can be transmitted to a side of the vehicle facing away from the crash.

[0010] According to a first aspect of the invention, the stacking direction of the cell stack can be aligned in the transverse direction of the vehicle. In this case, the force transmission segment forms a longitudinal beam segment. In a frontal crash, the longitudinal beam segment is integrated into a longitudinal load path via which the longitudinal crash force can be transmitted to the side of the vehicle facing away from the crash.

[0011] According to a second aspect of the invention, the stacking direction of the cell stack can be aligned in the longitudinal direction of the vehicle. In this case, the force transmission segment forms a crossbeam segment. In a side-impact collision, the crossbeam segment is integrated into a transverse load path via which the side-impact force can be transmitted to a side of the vehicle facing away from the crash.

[0012] It should be emphasized that the core of the invention is aimed particularly – but not exclusively – at a high-voltage battery whose battery cell modules each have cell stacks in which the battery cells are stacked one behind the other in a stacking direction aligned with the longitudinal direction of the vehicle. This may be necessary due to the structural conditions of the vehicle body in order to achieve the highest possible battery cell packing density and thus the highest possible battery performance. Therefore, at least one crossmember segment is assigned to the cell stack of each battery cell module as a component separate from the battery cells. In a side-impact crash, the crossmember segment is integrated into a lateral load path via which the side-impact force is transferred to the side of the vehicle facing away from the crash.

[0013] For the sake of easier understanding, further features of the invention are described below, specifically for a power transmission segment realized as a crossbeam segment: In one technical implementation, the battery housing can accommodate not just one, but at least two or more battery cell modules arranged side-by-side in the transverse direction of the vehicle. In this case, the crossbeam segments of the battery cell modules can be aligned transversely to each other in the transverse direction of the vehicle, forming a crossbeam that is integrated into the lateral load path in the event of a side impact. Preferably, the crossbeam segment can be positioned approximately centrally in the stack direction. In this case, the same number of battery cells are arranged on both sides of the crossbeam segment in the stack direction.

[0014] In a technical implementation, the high-voltage battery can be installed in the vehicle's body structure as follows: The vehicle's floor structure can have a battery mounting compartment open towards the bottom of the vehicle, in which the high-voltage battery can be installed. This battery mounting compartment can be enclosed vertically by the vehicle floor, which defines the vehicle interior. Furthermore, the battery mounting compartment can be bounded laterally by side frame members. In the event of a side impact, the side impact force can thus be transferred from the frame member facing the impact to the frame member facing away from the impact via the lateral load path.

[0015] In a first design variant, the crossmember segments can be separate components. These can be spaced apart from each other by a transverse gap during normal driving. Furthermore, the outermost crossmember segment in the vehicle's transverse direction can be spaced from the respective longitudinal body member by a transverse assembly clearance during normal driving. In this case, a side-impact trajectory results in which, at the moment of impact, the longitudinal body member facing the impact, the crossmember segments, and the longitudinal body member facing away from the impact are integrated into the lateral load path, thereby utilizing the transverse assembly clearance and / or the transverse gap.

[0016] In a second embodiment, at least one of the crossmember segments can be extended with a transverse overhang in the vehicle's transverse direction, bridging the transverse gap at least partially, and in particular completely, even during normal driving operation. In this case, the crossmember segment can extend laterally beyond the battery cells in the vehicle's transverse direction with its overhang.

[0017] In a third design variant, the crossbeam segments can no longer be realized as separate components. Instead, the crossbeam segments can be connected to each other in a single piece and / or made of the same material via at least one connecting web.

[0018] The battery cell module, at least one of which is located in the battery housing, can be constructed as follows: The battery cell module can have a clamping unit that clamps the battery cells and the crossbeam segment of the cell stack against each other in the stacking direction. This allows the battery cell module to be easily handled as a compact unit during battery assembly and inserted into the battery housing semi- or fully automatically. The clamping unit can have two end-face pressure plates between which the cell stack extends. The pressure plates can be connected to each other via clamping elements (for example, tension bands) arranged on both sides of the cell stack, thereby creating tension within the cell stack. This preload within the cell stack also prevents the crossbeam from buckling.This allows it to be made thinner compared to a freestanding "bend bar" / crossbeam.

[0019] In a preferred embodiment, the pressure plates of the clamping unit can also serve a dual function as crossbeam segments.

[0020] To protect the battery housing from mechanical damage caused by ground contact, a plate-shaped underride guard can be positioned below the base of the battery housing in the vehicle's vertical direction. This plate-shaped underride guard can be positioned downwards from the base of the battery housing by a deformation clearance. In the event of ground contact, a road-side obstacle (such as a bollard or curb) can exert an upward impact force, deforming the plate-shaped underride guard into this deformation clearance.

[0021] To increase the deformation resistance of the plate-shaped underride guard, a support element can be arranged within the deformation clearance. This support element can be positioned vertically in the vehicle's vertical direction, aligned with the crossmember segment. In the event of a ground impact, the plate-shaped underride guard can thus be supported by the support element and, with the battery housing base positioned between them, by the crossmember segment. In this case, the ground impact force is transferred upwards into the vehicle body via a vertical load path. This vertical load path can incorporate the plate-shaped underride guard, the support element, the battery housing base, the crossmember segment, and any upper battery cover.

[0022] All of the above features of the invention are readily applicable to a power transmission segment implemented as a longitudinal beam segment: In such a power transmission segment implemented as a longitudinal beam segment, only the spatial orientation of the power transmission segment changes in order to provide a support function in the event of a frontal crash. The longitudinal beam segments of the battery cell modules can be aligned longitudinally with each other in the longitudinal direction of the vehicle, forming a longitudinal beam that is integrated into the longitudinal load path in the event of a longitudinal crash. Furthermore, the longitudinal beam segments of the longitudinal beam can be separate components that are spaced apart from each other by a longitudinal gap during normal driving operation. Additionally, the longitudinal beam segments can each be extended with a projection in the longitudinal direction of the vehicle, at least partially, and in particular completely, bridging the longitudinal gap.Alternatively, the longitudinal beam segments can be implemented not as separate components, but rather connected to each other in a single piece via at least one connecting web, using the same material.

[0023] Exemplary embodiments of the invention are described below with reference to the accompanying figures.

[0024] They show: Fig. 1. A vehicle with a high-voltage battery installed in it, shown in a side view with partial elevation; Fig. 2 in a perspective view the high-voltage battery in isolation as well as with the battery housing top omitted; Fig. 3 in an exploded view a battery cell module; Fig. 4 a sectional view along the cutting plane AA from the Fig. 1; Fig. 5 and Fig. 6a each views according to the Fig. 4; Fig. 6b and Fig. 6c each shows detailed views; and Fig. 7 a perspective view of a high-voltage battery with plate-shaped underride protection.

[0025] In the Fig. Figure 1 shows a two-track vehicle in a side view. The vehicle has a rear compartment 1 with an indicated rear seat 3. The rear seat 3 is arranged on a body floor assembly, which is partially visible in the elevation view of vehicle 1. The body floor assembly is in the Fig. 1 only indicated to the extent necessary for understanding the invention.

[0026] In the Fig. 1 The body floor assembly has a rear panel part 5, the underside of which has a mounting space 7 open towards the bottom of the vehicle ( Fig. 4a or Fig. 4b) for a high-voltage battery 9. The battery mounting space 7 is defined in the transverse direction y towards the outside of the vehicle by rear longitudinal body members 11 ( Fig. 4a or Fig. 4b) limited. As can be seen from the Fig. As further shown in 4a, the high-voltage battery 9 is mounted at a connection point B on a plate-shaped underride guard 10 on the underside of the vehicle, which is attached directly to the battery and forms part of the ZSB battery system.

[0027] The following will be based on the Fig. 2 to Fig. 4b The structure of the battery housing 13 of the high-voltage battery 9 is described: Accordingly, the battery housing 13 has in the Fig. 4a a surrounding housing frame 15, which can be implemented as an aluminum casting. The surrounding housing frame 15 is in the, in the Fig. In the installation position shown in 4a, the battery is positioned at approximately the same height as the rear longitudinal body member 11. A housing upper part 17 is mounted on the top of the housing frame 15, and a housing base 19 is mounted on its underside. These define a battery compartment in which the Fig. 2 a total of four battery cell modules 21 are arranged.

[0028] In the Fig. Figure 3 shows the battery cell module 21 in an exploded view comprising a cell stack with a plurality of battery cells 23. These are stacked one behind the other in a stacking direction aligned with the longitudinal direction x of the vehicle. A crossbeam segment 25, separate from the battery cells 23, is arranged approximately centrally in the cell stack. The crossbeam segment 25 is preferably an extruded plate. Viewed in the stacking direction, the same number of battery cells 23 are positioned on each side of the crossbeam segment 25. A clamping unit 27 is also associated with the battery cell module 21, by means of which the battery cells 23 and the crossbeam segment 25 of the cell stack are clamped against each other in the stacking direction. The clamping unit 27 has in the Fig. 3 Two end-face pressure plates 29 are mounted, between which the cell stack extends. The two pressure plates 29 are connected to each other by tension bands 31 arranged on both sides of the cell stack, creating tension within the cell stack. In the assembled state, the battery cell module 21 is fastened to the housing base 19 by means of screw bolts 33. The screw bolts 33 pass through the pressure plates 29 and are screwed into screw bosses formed on the housing base 19 (not shown).

[0029] As from the Fig. As can be seen from Figure 4, the crossbeam segments 25 of the battery cell modules 21 are aligned in the transverse direction y of the vehicle in a transverse alignment, forming a crossbeam 35 which in a side crash in the transverse load path L y ( Fig. 4b) is integrated. In normal driving operation, the ones in the Fig. The four crossbeam segments 25 shown are spaced apart from each other by a transverse gap s. In normal driving operation, the outer crossbeam segments 25 of the crossbeam 35, located in the vehicle's transverse direction y, are spaced from their respective associated longitudinal body members 11 by a transverse assembly clearance m. In the event of a side impact, the longitudinal body member 11 facing the impact, the crossbeam segments 25, and the longitudinal body member 11 facing away from the impact are forced into the transverse load path L, with the transverse assembly clearance m and the transverse gap s being fully utilized. y integrated. To improve crash performance, a force introduction structure 39 (only in the Fig. 2 shown) trained.

[0030] In the Fig. Figure 5 shows a further embodiment of the invention in which the crossbeam segments 25 are extended beyond the battery cells 23 by a projection 37 in the transverse direction y of the vehicle. In this way, the transverse gap s between the battery cells 23 is bridged.

[0031] To further improve crash performance, the following features are included in the Fig. 6a The crossbeam segments 25 are no longer realized as separate components. Rather, the crossbeam segments 25 are connected to each other in a single piece and / or made of the same material via connecting webs 41.

[0032] This results in a situation that is Fig. 6a or Fig. Figure 6b shows a single-piece, material-uniform crossbeam 35, which extends inside the battery housing 13 in the transverse direction y of the vehicle. Fig. Figure 6c shows the single-piece, material-uniform crossbeam 35 with the battery cells 23 omitted. Accordingly, the crossbeam segments 25 are spaced apart from each other in the transverse direction y of the vehicle by transverse gaps s. The clamping elements 31 of the clamping units 27 of the battery cell modules 21 are guided through the transverse gaps s. The transverse gaps s are bounded downwards by the connecting webs 41, which connect the crossbeam segments 25 to each other.

[0033] In the Fig. 6c, the pressure plates 29 of the battery cell modules 21, arranged side by side in the transverse direction y of the vehicle, are also realized as crossbeam segments in a dual function. According to the Fig. 6c are the pressure plates 29 of the battery cell modules 21 in relation to each other in a power-transmitting system.

[0034] As from the Fig. 1 or Fig. As further shown in Figure 7, the plate-shaped underride guard 10 is arranged in the vehicle's vertical direction z below the base 19 of the battery housing 13. The underride guard 10 is spaced downwards from the base 19 of the battery housing 13 by a deformation clearance 43. In the event of a ground contact, a road-side obstacle with an upward ground contact force deforms the underride guard 10 into the deformation clearance 43.

[0035] To increase the deformation resistance of the underride guard 10, a support element 45 is arranged in the deformation clearance 43. The support element 45 is designed as a transverse hollow beam which is attached to the plate-shaped underride guard 10. According to the Fig.7 The support element 45 is positioned in the vehicle's vertical direction z in line with the cross member 35. In the event of ground contact, the plate-shaped underride guard 10 is therefore supported by the support element 45 and, with the housing base 19 interposed, by the cross member 35. Reference symbol list 1. Rear compartment 3 Rear seat 5 Rear panel part 7 Battery mounting room 9 high-voltage battery 10 plate-shaped underride guards 11 Body longitudinal members 13 Battery housings 15 housing frames 17 Housing top 19 Case base 21 battery cell module 23 battery cells 25 Power transmission segment 27 clamping unit 29 printing plates 31 clamping elements 33 screw bolts 35 crossbeams 37 Overhang 39 Force introduction structure 41 connecting bridges 43 Deformation clearance 45 Support element B Connection point s transverse gap m assembly free passage L y , L x Crash load path QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 102016223220 A1

[0006] DE 102018112377 A1

[0006] DE 102016009930 A1

[0006]

Claims

[1] High-voltage battery (9) for an electrically powered vehicle, comprising a battery housing (13) in which at least one battery cell module (21) is arranged, which has a cell stack comprising a plurality of battery cells (23) stacked one behind the other in a stacking direction, characterized by , that in the cell stack at least one power transmission segment (25) is arranged as a component separate from the battery cells (23), and that the power transmission segment (25) is located in a crash load path (L) in the event of a crash y , L x ) is integrated, via which the crash force (F S ) is transferable to a side of the vehicle facing away from the crash. [2] High-voltage battery according to claim 1, characterized by, that the stacking direction of the cell stack is aligned in the vehicle transverse direction (y) such that the force transmission segment (25) forms a longitudinal beam segment, and that the longitudinal beam segment (25) in a frontal crash case in a longitudinal load path (L x ) is integrated, via which the longitudinal crash force (Fs) can be transferred to the side of the vehicle facing away from the crash. [3] High-voltage battery according to claim 1, characterized by , that the stacking direction of the cell stack is aligned in the longitudinal direction (x) of the vehicle, so that the power transmission segment (25) forms a crossbeam segment, and that the crossbeam segment (25) in a side crash case in a lateral load path (L y ) is integrated, via which the side crash force (F S ) is transferable to a side of the vehicle facing away from the crash. [4] High-voltage battery according to claim 3, characterized by, that in the battery housing (13) at least two battery cell modules (21) are arranged side by side in the transverse direction (y) of the vehicle, and that the cross member segments (25) of the two battery cell modules (21) are aligned transversely to each other in the transverse direction (y) of the vehicle, forming a cross member (35) which in the event of a side crash in the lateral load path (L y ) is integrated. [5] High-voltage battery according to claim 3 or 4, characterized by, that the high-voltage battery (9) can be installed in a battery mounting compartment (7) open downwards in a vehicle floor structure of the vehicle, and that the mounting compartment (7) is closed off in the vehicle's vertical direction (z) upwards by a vehicle floor (5) that defines the vehicle interior, and / or that the battery mounting compartment (7) is limited in the vehicle's transverse direction (y) by lateral body longitudinal members (11), and / or that, in particular in the event of a side crash, the side crash force (Fs) is transferred from the crash-facing body longitudinal member (11) via the lateral load path (L) y ) can be transferred to the longitudinal body member (11) facing away from the crash. [6] High-voltage battery according to claim 3, 4 or 5, characterized by, that the crossmember segments (25) of the crossmember (35) are separate components, and / or that in normal driving operation the crossmember segments (25) are spaced apart from each other by a transverse gap (s), and / or that the crossmember segment (25) of the crossmember (35) located on the outside in the vehicle transverse direction (y) is spaced apart from the respective body longitudinal member (11) by a transverse assembly clearance (m) in normal driving operation, and / or that in the event of a side crash the crash-facing body longitudinal member (11), the crossmember segments (25) and the crash-away body longitudinal member (11) transmit force in the transverse load path (L) by utilizing the transverse assembly clearance (m) and / or the transverse gap (s). y are integrated. [7] High-voltage battery according to any one of the preceding claims, characterized by, that at least one crossbeam segment (25) is extended with a projection (37) in the transverse direction (y) of the vehicle, at least partially, in particular completely, bridging the transverse gap (s), and that in particular the crossbeam segment (25) laterally extends beyond the battery cells (23) with its projection (37). [8] High-voltage battery according to any one of the preceding claims, characterized by , that the crossbeam segments (25) are not realized as separate components, but the crossbeam segments (25) are connected to each other in a single material and / or one-piece manner via at least one connecting web (41). [9] High-voltage battery according to any one of the preceding claims, characterized by, that the battery cell module (21) has a clamping unit (27) with which the battery cells (23) and the crossbeam segment (25) of the cell stack are clamped against each other in the stacking direction, and that in particular the clamping unit (27) has two end-face pressure plates (29) between which the cell stack extends, and that the pressure plates (29) are connected to each other via clamping elements (31) arranged on both sides of the cell stack, thereby creating tension in the cell stack. [10] High-voltage battery according to claim 9, characterized by , that the pressure plates (29) of the clamping unit (27) are additionally designed as crossbeam segments (25) in a dual function, and / or that the crossbeam segment (25) is positioned centrally in the cell stack, and / or that the same number of battery cells (23) are arranged on both sides of the crossbeam segment (25) in the stacking direction. [11] High-voltage battery according to any one of the preceding claims, characterized by , that in the vehicle's vertical direction (z) below the base (19) of the battery housing (13) a plate-shaped underride guard (10) is arranged, which is spaced downwards from the base (19) of the battery housing (13) by a deformation clearance (43), and that in the event of ground contact, a road-side disturbance contour, in particular a bollard or a curb, with a ground contact force directed upwards towards the vehicle, deforms the plate-shaped underride guard (10) into the deformation clearance (43). [12] High-voltage battery according to claim 11, characterized by, that to increase the deformation resistance of the underride guard (10) a support element (45) is arranged in the deformation clearance (43), and that in particular the support element (45) is positioned in the vehicle's vertical direction (z) in line with the cross member segment (25), and that in particular in the event of the underride guard (10) hitting the ground, it can be supported by the support element (45) and by the housing base (19) on the cross member segment (25). [13] Vehicle with a high-voltage battery (9) according to any of the preceding claims.