Arrangement of cell layers relative to each other in a high-voltage battery for a motor vehicle

Abstract

The invention relates to a high-voltage storage device for arrangement in an electrically driven motor vehicle, comprising at least two superimposed cell layers, each with a plurality of cylindrical battery cells having a vent end face and a pole end face, characterized in that the vent end faces of the battery cells of two adjacent cell layers are arranged in a mutually oriented manner.

Description

[0001] The invention relates to a high-voltage storage device for arrangement in an electrically driven motor vehicle, comprising at least two superimposed cell layers, each with a plurality of cylindrical battery cells, each having a vent which enables degassing along the longitudinal axis of the battery cell starting from one of the end faces of the battery cell.

[0002] High-voltage storage systems for electric vehicles are known from the prior art, each comprising several cylindrical battery cells typically arranged in a single layer within a housing. These high-voltage storage systems serve to store energy for powering the vehicle and are usually located in the vehicle floor in a longitudinal area between the two axles, below the seats for the vehicle occupants.

[0003] Such an arrangement of the high-voltage battery is generally unproblematic in many vehicles because their intended center of gravity is sufficiently low due to the high weight of the high-voltage battery, so that the relatively high arrangement of the seats is unproblematic or even perceived as advantageous for a better view for the driver.

[0004] However, the placement of the high-voltage battery presents a particular challenge for high-performance vehicles, especially super sports cars. Positioning the high-voltage battery in the vehicle floor would therefore protrude significantly in the vehicle's vertical direction and, due to the driver's seat being positioned above it, would result in a center of gravity that is too high (especially for a super sports car), thus impairing the desired high level of driving dynamics and stability.

[0005] Against this background, it is an object of the invention to improve the high-voltage storage system of the motor vehicle in such a way as to enable a more advantageous center of gravity of the motor vehicle.

[0006] The independent claim, with its features, defines an object that solves this problem. The dependent claims relate to advantageous embodiments of the invention.

[0007] According to the invention, a high-voltage storage device for installation in an electrically powered motor vehicle is disclosed, comprising at least two stacked cell layers, each with a plurality of cylindrical battery cells. The cylindrical battery cells each have a vent end face from which, starting at a vent (as a predetermined breaking point for degassing in the event of thermal runaway of the battery cell), degassing along the longitudinal axis of the battery cell is possible. Furthermore, the battery cells each have a pole end face with a pole arrangement that enables contacting the battery cell.

[0008] The vent end faces of, in particular all, battery cells of two adjacent cell layers are arranged in an orientation towards each other, i.e. in particular that the end faces of the battery cells on which the vent is formed are arranged in an orientation towards each other.

[0009] By aligning the vent end faces with each other, a single degassing channel can be formed for the two adjacent cell layers, which is sufficient to remove particles and heat energy from a thermal event of battery cells in both cell layers.

[0010] According to one interpretation, the height of the common degassing channel can be dimensioned in the same way as the height of a degassing channel for the battery cells of only one cell layer - because in both cases, initially only sufficient space needs to be provided to dissipate the heat energy and particles from a failing battery cell.

[0011] Furthermore, by aligning the vent end faces with each other, the area in the high-voltage storage system that needs to be made temperature-resistant or fire-resistant can be reduced, particularly compared to high-voltage storage systems where the vent in all cylindrical battery layers is oriented in the same direction, and therefore the space between all cell layers must be made temperature-resistant or fire-resistant. In contrast, with the high-voltage storage system according to the invention, it is sufficient to protect only every second space between two cell layers against a thermal event and to provide a degassing path there.

[0012] According to one embodiment, a degassing channel is arranged between the two adjacent cell layers to remove hot particles and gases from a thermal event. By positioning the discharge channel between the two adjacent cell layers, they are further separated from each other, so that hot particles and gases that might escape from the vent of one battery cell in the event of a thermal event have the opportunity to disperse / diffusion and / or cool down upon impact with the opposite cell layer. In this way, the peak thermal load occurring upon impact can be slightly reduced.

[0013] According to one embodiment, a cell contacting system is formed between at least one or each of the two adjacent cell layers on the one hand and, on the other hand, a cell layer of the high-voltage storage device arranged thereon at its pole end face, by which the battery cells of these two cell layers are electrically contacted at their mutually oriented pole end faces. In particular, the cell contacting systems are formed on those end faces of the cell layers that face away from the respective associated degassing channel.

[0014] According to one embodiment, the cell contacting system is designed for the joint contacting of the cells of both adjacent cell layers at their pole ends. This joint contacting at the mutually facing electrical contact points of the cells of the two cell layers adjacent at their pole ends results in further potential savings in terms of installation space in the vertical direction of the high-voltage storage system and thus also in the vehicle as a whole.

[0015] In this context, "common contacting" means in particular that at least part of the conductor paths is used to contact the adjacent cell layers when contacting one or more battery cells of both adjacent cell layers.

[0016] According to one embodiment, the longitudinal axes of the battery cells of the two adjacent cell layers are arranged offset from each other.

[0017] The offset arrangement of the battery cells' longitudinal axes ensures that a primary degassing path via the vent of one battery cell does not directly collide with a vent of the adjacent cell layer located along the same longitudinal axis. By preventing such a direct collision, the probability of propagation due to overheating of the opposing battery cell in the primary degassing path is reduced. Furthermore, due to the offset, there is no directly opposing battery cell.

[0018] The invention is based, among other things, on the consideration that for an advantageous arrangement of the high-voltage storage system in super sports cars, the battery cells should be arranged vertically on top of each other in several cell layers behind the seat.

[0019] In particular, cylindrical battery cells typically have a predetermined breaking point (also called a vent) at the bottom. In the event of a thermal incident (explosive cell degassing), this opening ruptures, and hot gas and particles are released in the form of a flame. In this case, the gases and particles must be able to be vented from the high-voltage storage system, for example, via a degassing channel.

[0020] The invention is based, among other things, on the idea of ​​arranging the first cell layer of each cell layer pair (or, in the case of more than two cell layers, the first, third, fifth, etc.) inverted – that is, upside down. This allows a single degassing channel to be shared by two opposing cell layers. Theoretically, the overall height of the battery storage system can be reduced by the height of one degassing channel (or, in the case of a larger number of cell layers, by the heights of several saved degassing channels) in the vehicle's vertical direction, thus achieving a lower center of gravity for the vehicle.

[0021] Furthermore, in high-voltage storage systems with at least three cell layers, additional installation space in the vehicle's vertical direction can be saved according to one design, by having two adjacent cell layers have a jointly formed cell contacting system on their mutually adjacent pole end faces, which, due to the partially shared design of certain conductor sections, can be less voluminous and therefore less tall.

[0022] According to one design, the cells of the next higher level are arranged so that they are offset from the lower level in order to direct the jet of flame described above not directly at the cell below, but at an intermediate structure / sacrificial structure.

[0023] According to one embodiment, the longitudinal axes of the battery cells of the two adjacent cell layers are arranged such that a center of a degassing flame, in particular along a longitudinal axis of the battery cell, primarily impacts between the battery cells of the adjacent cell layer, in particular at a cell support structure of the cell layer.

[0024] This simplifies the propagation-inhibiting design of the high-voltage storage system, especially because it is much easier and more economically feasible to design a cell support structure to be temperature-resistant or fire-resistant than an end face of a battery cell - which is also intended to serve as a predetermined breaking point for releasing the battery cell.

[0025] According to one embodiment, the vent axes, in particular the longitudinal axes of the battery cells, of one of the two adjacent cell layers are arranged at a maximum offset to the vent axes of the other of the two adjacent cell layers.

[0026] This ensures that as high a proportion as possible of the hot particles and gases exiting the vent are directed at the cell support structure, and not at the opposite, facing vent.

[0027] According to one design, the battery cells of the cell layers are arranged in a rectangular matrix shape relative to each other.

[0028] According to one embodiment, the battery cells of the cell layers are arranged in a rectangular matrix shape relative to each other, and / or the offset of the two adjacent cell layers relative to each other is half a cell distance with respect to one of the matrix axes.

[0029] This means that, for example, a certain inhibition of the propagation tendency can be achieved even without an offset in the transverse direction or in the longitudinal direction with an offset in the opposite direction.

[0030] According to one embodiment, the battery cells of the cell layers are arranged in a rectangular matrix shape relative to each other, and / or the offset of the two adjacent cell layers is half a cell distance with respect to both matrix axes.

[0031] By maximizing the offset over the entire area, optimized inhibition of propagation tendency can be achieved for a given cell packing in a rectangular matrix shape. The offset is then designed such that the vent axes of the second adjacent cell layer pass precisely through the centroid of the base rectangle of the rectangular matrix of the first adjacent cell layer.

[0032] According to one embodiment, the battery cells of the cell layers are arranged in a hexagonal packing relative to each other.

[0033] According to one embodiment, the battery cells of the cell layers are arranged in a hexagonal packing relative to each other, and / or the offset of the two adjacent cell layers relative to each other is half a cell distance with respect to a longitudinal direction and / or a transverse direction of the hexagonal packing.

[0034] This means that, for example, a certain inhibition of the propagation tendency can be achieved even without an offset in the transverse direction or in the longitudinal direction with an offset in the opposite direction.

[0035] According to one embodiment, in particular the battery cells of the cell layers are arranged in a hexagonal packing relative to each other, and / or the offset of the two adjacent cell layers relative to each other is a quarter of a cell spacing with respect to a longitudinal direction and / or a transverse direction of the hexagonal packing.

[0036] By maximizing the offset over the entire area, optimized inhibition of propagation tendency can be achieved for a given cell packing in a hexagonal packing. The offset is then designed such that the vent axes of the second adjacent cell layer pass precisely through the centroid of the base triangle of the hexagonal packing of the first adjacent cell layer.

[0037] According to one embodiment, a multi-layered high-voltage storage device is provided, which has at least two or four or six or eight or more cell layers offset from each other.

[0038] According to one embodiment, the multilayer high-voltage storage system is designed such that the cell layers, or battery cells, with their thermal expansion valves (also referred to here as vents or cell vents), are positioned relative to each other and utilize a common degassing channel. According to this embodiment, the degassing channel simultaneously serves as the central support structure for the two cell layers involved. This allows for a simple design of the high-voltage storage system.

[0039] According to one embodiment, the degassing channel is equipped with a thermal protection layer and / or a thermal protection structure that simultaneously prevents larger particles or entire cell windings from damaging the opposing thermal protection structure. According to one embodiment, the thermal protection layer and / or the thermal protection structure can be bonded into the common degassing channel.

[0040] According to one embodiment, the cells are glued into a support structure on the opposite side (in one embodiment at the positive pole), which simultaneously accommodates the cell contacting system (CCS), resulting in a stable assembly.

[0041] According to one embodiment, the multi-layer high-voltage storage unit is designed in such a way that the central storage unit is protected with a cover, which, according to another embodiment, is screwed to the central support structure (with integrated degassing channel).

[0042] According to one embodiment, the protective covers are shaped in such a way that they interlock geometrically in the XY plane between the cell layers, or between the lowest cell layer and a shear field / crash structure, or between the uppermost cell layer and a storage housing, in particular a housing pot.

[0043] According to one embodiment, the multi-layer high-voltage storage system is designed such that the cell layers are pre-tensioned vertically from the top of the storage housing (e.g., by means of screws, spring force, or similar). According to this embodiment, the housing, due to its inherent stiffness, is capable of creating a force-fit connection between this pre-tension and the shear field.

[0044] According to one design, the multi-layered high-voltage storage system is designed so that the storage housing can be additionally supported on the top side towards the vehicle in order to support any lateral and / or longitudinal loads up to and including crash loads.

[0045] According to one design, the multi-layered high-voltage storage system is designed so that the thrust panel is firmly screwed into the vehicle and can bear all the loads from the storage system.

[0046] According to one embodiment, the multi-layered high-voltage storage system is designed such that the crash structure is geometrically interlocked in the XY plane with the ZKS protective covers and / or the thrust field.

[0047] According to one embodiment, the multi-layer high-voltage storage device is designed such that by gluing the battery cells into the support structure, a dense, in particular self-contained, degassing channel is created, which is arranged particularly vertically between two cell layers.

[0048] According to one embodiment, the multi-layer high-voltage storage device is designed such that the degassing channels of each pair of adjacent cell layers are combined by means of a degassing collection channel and / or the degassing path is jointly discharged into the atmosphere via a degassing valve.

[0049] According to one embodiment, the multi-layered high-voltage storage system is designed such that the cell axes of the cell layers are either concentric or offset in the longitudinal and / or transverse direction of the vehicle. If they are offset, according to another embodiment, an additional offset protective layer (made of, for example, Mika, carbon and / or aluminum or steel) is to be bonded to the side of the opposite cell to prevent the structural support (also referred to here as the cell support structure) between the cells from burning through in the event of a thermal event in one cell.

[0050] According to one embodiment, the multi-layer high-voltage storage system is designed such that the degassing channel and / or the opposing cell layers are additionally bonded to the cell with a thermally protective layer carrier, which can mechanically retain larger pieces during the thermal event of a cell. These protective layer carriers can be used on both sides or on one side, depending on the specific design.

[0051] In this context, cell position refers in particular to all battery cells that are arranged on one plane with respect to a vehicle's vertical axis.

[0052] In particular, each cell layer can be designed as a cell pack of several battery cells and / or several cell packs can be arranged one above the other, especially in such a way that only a single cell pack is arranged for each vehicle height.

[0053] Further advantages and application possibilities of the invention will become apparent from the following description in conjunction with the figures: Fig. Figure 1 shows a supercar with a known high-voltage storage system in a cutaway side view. Fig. Figure 2 shows a super sports car with a high-voltage storage system according to an exemplary embodiment of the invention in a cutaway side view. Fig. Figure 3 shows the high-voltage storage according to Fig. 2 in a side view. Fig. 4 shows the high-voltage storage according to Fig. 2 in an isometric oblique view. Fig. Figure 5 shows a cutaway side view of an assembly consisting of a seat of the supercar and the high-voltage storage unit according to Fig. 2. Fig. Figure 6 shows in a cutaway side view an assembly consisting of a seat of the super sports car and a high-voltage storage device according to a further exemplary embodiment of the invention. Fig. Figure 7 shows individual battery cells of adjacent cell layers of the high-voltage storage system. Fig. 2 in the case of a thermal event of a battery cell in a sectional view. Fig. Figure 8 shows a section of the high-voltage storage system with four cell layers made of Fig. 2 with the degassing channels in a cutaway side view. Fig. Figure 9 shows a section of the high-voltage storage system. Fig. 6 with a degassing channel having a thermal protection arrangement according to an exemplary embodiment, in a schematic, cutaway side view. Fig. Figure 10 shows a section of the high-voltage storage system. Fig. 2 with a degassing channel which has a thermal protection arrangement according to a first exemplary embodiment, in a cut side view. Fig. Figure 11 shows a section of the high-voltage storage system. Fig. 2 with a degassing channel which has a thermal protection arrangement according to a second exemplary embodiment, in a cut side view. Fig. Figure 12 shows a section of the high-voltage storage system. Fig. 2 with a degassing channel which has a thermal protection arrangement according to a third exemplary embodiment, in a cut side view. Fig. Figure 13 shows a section of the high-voltage storage system. Fig. 6 with a serial interconnection of the individual cell layers to each other, as is known in itself, in a cut side view. Fig. Figure 14 shows a section of the high-voltage storage system. Fig. 6 with a serial interconnection of the individual cell layers to each other according to a first exemplary design variant, in a cut side view. Fig. Figure 15 shows a section of the high-voltage storage system. Fig. 6 with a serial interconnection of the individual cell layers to each other according to a second exemplary design variant, in a cut side view. Fig. 16 shows the high-voltage storage unit Fig. 2 without the housing pot in a perspective oblique view. Fig. Figure 17 shows an enlarged detail view of a section of the Fig. 16, in which in particular a degassing collection channel of the high-voltage storage unit is more clearly visible. Fig. Figure 18 shows the degassing collection channel. Fig. 16 in a cutaway view from above, relating to an installation hole in the vehicle. Fig. Figure 19 shows the degassing collection channel. Fig. 16 in a cutaway view from the front, referring to an installation position in the vehicle. Fig. Figure 20 shows the force connections in the different spatial directions in the high-voltage storage system. Fig. 2 in a cutaway side view. Fig. Figure 21 shows a ZKS holder plate between two cell layers of the high-voltage storage system. Fig. 2 in a cutaway view from above.

[0054] Fig. Figure 1 shows a state-of-the-art, fully electric supercar 1*. The high-voltage storage system 2* of the well-known supercar 1* is – as with many other known, fully electric vehicles – located in the vehicle floor in a longitudinal area between the two axles, below the seats 4* for the vehicle occupants.

[0055] Such an arrangement of the high-voltage battery is generally unproblematic in many vehicles because their intended center of gravity is sufficiently low due to the high weight of the high-voltage battery, so that the relatively high arrangement of the seats is unproblematic or even perceived as advantageous for a better view for the driver.

[0056] The situation is different for super sports cars, for which the lowest possible center of gravity is the goal. The elevated seating position above the high-voltage battery, as in the well-known super sports car, contradicts an optimized low center of gravity.

[0057] Fig. Figure 2 shows a purely electrically powered super sports car 1 in which an exemplary embodiment of the invention is implemented.

[0058] Unlike the well-known super sports cars according to Fig. 1 is in the supercar 1 of the Fig. 2 The high-voltage storage unit 2 for supplying energy to a drive system of the super sports car 1 is not located below the seats or seat 4, but behind them.

[0059] This allows the seat(s) to be positioned lower in the vehicle. This lowers the vehicle's center of gravity, which can improve cornering agility. It also allows the vehicle to be lower overall, which, with the same engine power, can lead to improved aerodynamics and potentially better acceleration and / or a higher top speed for the supercar.

[0060] Fig. It can also be seen from Figure 2 that the high-voltage storage device 2, and in particular its housing 6 shown here, is inclined in the same direction as the backrest 5 of the seat 4, at least on the side facing that backrest 5. The inclination refers to a YZ plane of the vehicle, the extent of which is considered to be uninclined for the purposes of describing the inclination.

[0061] In this case, the high-voltage storage unit 2 is inclined at an angle alpha to the YZ plane of the vehicle. This allows for a similar or identical inclination of the backrest 5 of the seat 4 without requiring the seat 4 to be installed further forward in the vehicle (assuming the X-position of the high-voltage storage unit remains constant).

[0062] Fig. Figure 3 shows the high-voltage storage unit 2 with its housing 6 and a coolant connection 8 in a side view from the left side of the vehicle.

[0063] Even more clearly than in Fig. Figure 2 shows the inclination of the outer wall of the housing 6 facing the seat 4 by the angle alpha to the YZ plane of the vehicle. The YZ plane is represented in the side view by a dotted dashed line.

[0064] Fig. Figure 4 shows the outer contour of the high-voltage storage device 2 and its housing 6 in an isometric oblique view. The coolant connection 8, located on the side of the housing 6 facing the seat 4, is again visible.

[0065] Fig. Figure 5 shows a comparison between a known high-voltage storage device 2* with an unsloped outer wall of a housing 6* and the high-voltage storage device 2 according to the exemplary embodiment of the invention, in which the outer wall of the housing 6 is inclined at the angle alpha to the YZ plane of the vehicle.

[0066] The high-voltage storage device 2 has four cell layers A, B, C, and D arranged one above the other in the Z-direction, with an offset of a distance s in the X-direction between any two adjacent cell layers. Each of the cell layers A, B, C, and D has a plurality of battery cells 10A, 10B, 10C, and 10D, respectively, which are preferably, but not necessarily, arranged in a hexagonal packing.

[0067] Out of Fig. 5 shows that, due to this inclination, an assembly consisting of the seat 4 and the high-voltage storage unit 2 can be designed to be shorter by a longitudinal extent x than the known high-voltage storage unit 2* with the uninclined housing wall.

[0068] In the exemplary embodiment, the inclination of the outer wall of the housing 6 is made possible by arranging the different cell layers A, B, C, and D offset from each other by half a distance s of the longitudinal axes of adjacent battery cells 10. Specifically, the longitudinal axes of the battery cells 10 in cell layer A are offset from the longitudinal axes of the battery cells 10 in cell layer B by half a distance s of the longitudinal axes of adjacent battery cells 10. Similarly, cell layer B is offset from cell layer C by half a distance s of the longitudinal axes of adjacent battery cells; and cell layer C is offset from cell layer D accordingly.

[0069] Fig. Figure 6 shows, in comparison with the known high-voltage storage device 2*, a high-voltage storage device 2' in which the outer wall of the housing 6' can be inclined even more strongly because the adjacent cell layers are not only offset by half a distance s of the longitudinal axes of the adjacent battery cells, but by a whole distance 2s of the longitudinal axes of the adjacent battery cells.

[0070] On the in Fig. As shown in Figure 6, an assembly consisting of the seat 4 and high-voltage storage 2' can be made shorter by a longitudinal extent x', where the longitudinal extent x' is greater than the longitudinal extent x from Fig. 5.

[0071] Fig. Figure 7 shows a section of the battery cell arrangement in cell layers A and B of the high-voltage storage system 2 according to Fig. 2, as in Fig. Figure 5 shows: the longitudinal axes of the battery cells 10 of cell position A are arranged offset by half a distance s of the longitudinal axes of adjacent battery cells 10 to the longitudinal axes of the battery cells 10 of cell position B.

[0072] Shown are one cell 10A.1 of cell layer A and two cells 10B.1 and 10B.2 of cell layer B. The cell layers A and B are arranged in the high-voltage storage unit 2 separated in the vertical direction Z by the degassing channel 14_AB.

[0073] The cells 10A of cell layer A are contained in a cell support structure 12A, which is in Fig. 7 is only symbolically and partially represented. The cells 10B of cell layer B are contained in a cell support structure 12B, which is in Fig. 7 is also only symbolically and partially represented.

[0074] In the Fig. Figure 7 depicts the case of a thermal event (also known as thermal runaway) of cell 10A.1, in which heat energy and hot material are introduced into the degassing channel 14_AB at high speed. This is symbolically represented by the flame T_AB.

[0075] Due to the offset of the cells 10 A of cell layer A to the cells 10 B of cell layer B by the distance s, the main part of the energy and matter of the thermal event of cell 10 A is directed against the cell support structure 12 B, and not against a cell 10 B, as would be the case with a conventional longitudinally axially aligned arrangement of the adjacent cell layers A and B.

[0076] Unlike battery cells, which are directly subjected to thermal energy at their cylindrical end face, the cell carrier structure 12 B can be designed with a technically and economically reasonable effort to effectively protect it against the introduction of thermal energy or hot matter at high speed.

[0077] Thus, effective propagation protection can be achieved by arranging the cell layers A and B offset from each other by a distance s. Exemplary detailed embodiments of a cell support structure 12 effective as propagation protection, which has thermal protection arrangements 17, 117, 217 and 317 with thermal protection layers 18, 118, 218 and 318 respectively, are described below. Fig. 9, Fig. 10, Fig. 11 and Fig. 12 explained in more detail.

[0078] Fig. Figure 8 schematically shows a section of the high-voltage storage unit 2. Fig. 2 with four cell layers A, B, C and D.

[0079] Cells 10A and 10B of cell layers A and B are aligned with each other such that their contact-away cylindrical end faces - which in particular have a target failure point for thermal events within the cell, i.e. a vent side - are facing each other.

[0080] This means that the intended degassing points for all cells 10A and 10B of the two adjacent cell layers A and B are arranged in such a way that they can all degas into a common degassing channel 14_AB of the high-voltage storage unit 2.

[0081] The degassing channel 14_AB therefore serves as a degassing channel for two adjacent cell layers A and B. A second degassing channel for these two cell layers is no longer required. This saves the installation space for a second degassing channel in the vehicle's vertical direction Z.

[0082] Cells 10C and 10D of cell layers C and D are also aligned with each other in such a way that their contact-away cylindrical end faces - which in particular have a target failure point for thermal events within the cell - are facing each other.

[0083] This means that the intended degassing points for all cells 10C and 10C of the two adjacent cell layers C and D are arranged in such a way that they can all degas into a common degassing channel 14_CD of the high-voltage storage unit 2.

[0084] The degassing channel 14_CD therefore serves as a degassing channel for two adjacent cell layers C and D. A second degassing channel for these two cell layers is no longer required. This saves the installation space for a second degassing channel in the vehicle's vertical direction Z.

[0085] The high-voltage storage unit 2 therefore only has two degassing channels 14_AB and 14_CD - instead of four degassing channels, as in conventional four-layer high-voltage storage units.

[0086] The cell contacting systems 16_A, 16_BC and 16_D are each formed on those end faces of the cell layers A, B, C and D respectively that are facing away from the respective associated degassing channel 14_AB and 14_CD.

[0087] The mutually facing electrical contact points of cells 10 B of cell layer B and cells 10 C of cell layer C result in a further potential for saving space in the Z direction: the cell contacting system 16_BC can be designed to contact cells 10 B and 10 C together - and thus also be lower overall in the Z direction.

[0088] Both degassing channels 14_AB and 14_CD also exhibit the following characteristics due to the adjacent cell layers A and B, B and C, C and D being offset by a distance s. Fig. 7 described advantages regarding propagation protection.

[0089] The in Fig. However, the exemplary embodiment described in section 8 of a summary of the degassing channels of two adjacent cell layers can also be used in high-voltage storage systems with cell longitudinal axis alignment, regardless of any offset (be it by a distance s or another distance or without offset).

[0090] Due to the mutually facing contact sides of the cells 10B of cell layer B on the one hand and the cells 10C of cell layer C on the other hand in the high-voltage storage device 2 described here with four cell layers, a certain saving potential with regard to the installation space in the Z direction can be realized, in comparison with a high-voltage storage device whose cell layers are all oriented the same way along the Z-axis.

[0091] High-voltage storage devices not shown, of a design analogous to high-voltage storage device 2, but which have a larger number of cell layers, enable a multiple saving of the specified installation space in the Z-direction: for example, the specified installation space in the Z-direction can be saved twice in a high-voltage storage device with six cell layers, three times in a high-voltage storage device with eight cell layers, and four times in a high-voltage storage device with ten cell layers (etc...).

[0092] Fig. Figure 9 shows a section of the high-voltage storage unit 2' according to Fig. 6, whose cell axes are shifted by a full distance of 2s in the Z direction.

[0093] The diagram shows two adjacent cell layers A and B and the degassing channel 14_AB located between them. All cells 10A of cell layer A and all cells 10B of cell layer B are oriented with their vent side towards the degassing channel 14_AB. The degassing channel 14_AB is defined by the placement of the cells 10 within the respective cell support structures 12A and 12B.

[0094] At the two boundary planes of its Z-extension, the degassing channel is thermally insulated by means of a thermal protection layer 18A or 18B of a thermal protection arrangement 17A or 17B of the respective cell layer A or B.

[0095] The thermal insulation is designed to withstand thermal events such as a hot outgassing of cell 10B. 2 (as represented in the figure by the flame T_BA), even if the cell casing 20B. 2 is destroyed by the thermal event.

[0096] The material for the thermal protection layer 18 is characterized by low thermal conductivity and good electrical insulation properties. At the same time, the material exhibits relatively low mechanical strength against pressure applied in a direction normal to the extent of the material layer. This allows the thermally failing cell to expel hot gases and particles at its vent because the adjacent thermal protection layer 18B fails mechanically. The thermal protection layer 18A, located on the opposite side of the degassing channel 14_AB – which is not subjected to nearly as much pressure due to the distribution of gases and particles in the degassing channel – can then demonstrate its good thermal and electrical insulation properties.

[0097] Thus, propagation – which the cell casing 20 A. 2 of the opposite cell 10 A. 2 might otherwise have no defense against – is effectively prevented.

[0098] The thermal protective layers 18 comprise, in particular, a mica-containing material (also referred to as mica, especially with or made of phlogopite and / or muscovite) and / or a carbon-containing material and / or an aluminum and / or steel alloy, or consist of such a material. In the exemplary embodiment, the thermal protective layers 18 are made with or from mica, for example as mica films with phlogopite milled material applied to a carrier layer with glass fiber and adhesive.

[0099] In the Fig. 10, Fig. 11 and Fig. 12 is the same section of the high-voltage storage unit 2. Fig. 2 with a degassing channel 14_AB shown. The representations of the Fig. 10, Fig. 11 and Fig. 12 differ in the exemplary design of the thermal protection arrangement 117, 217 and 317. The thermal protection layers 118, 218 and 318 of the protection arrangements 117, 217 and 317 can be made of the same materials or the same material as the thermal protection layers 18 of the thermal protection arrangements 17. Fig. 9 trained.

[0100] Fig. Figure 10 shows thermal protection arrangements 117 for the high-voltage storage device 2 according to a first exemplary embodiment.

[0101] The thermal protection devices 117 are formed at the cell-side boundaries of the degassing channel 14_AB on the respective cell support structures 12A and 12B. The cell support structures 12 are each arranged around the longitudinal axes of the cells and have a recess in the area of ​​the cell vent to allow pressure reduction into the degassing channel 14_AB in the event of a thermal event.

[0102] To close these recesses for electrical insulation during normal operation, a thermal protection layer 118 of the thermal protection arrangement 117 is arranged on the cell support structures 12 (either separately for each recess as shown, or as a larger unit for several or all recesses together), in particular glued in place as shown here. In the illustrated embodiment, the thermal protection layers 118 are made with or from mica.

[0103] In the event of a thermal event affecting cell 10B.1 of cell layer B – represented here by the flame T_BA – the thermal protection layer 118B.2 fails due to the high pressure applied in the normal direction. As a result, the hot gases and electrically conductive particles propagate through and over time within the degassing channel 14_AB, impacting the cell support structure 12A and the thermal protection layers 118A.1 and 118A.2. Through a combination of pressure reduction caused by the distribution of the gases and particles within the degassing channel 14_AB and the high thermal and electrical insulation capacity of the thermal protection layers 118A.1 and 118A.2, the cells 10A of cell layer A are decoupled from the effects of the thermal event – ​​preventing both propagation and an unwanted short circuit.

[0104] Fig. Figure 11 shows thermal protection arrangements 217 for the high-voltage storage device 2 according to a second exemplary embodiment.

[0105] The thermal protection devices 217 are formed at the cell-side boundaries of the degassing channel 14_AB on the respective cell support structures 12A and 12B. The cell support structures 12 are each arranged around the longitudinal axes of the cells and have a recess in the area of ​​the cell vent to allow pressure reduction into the degassing channel 14_AB in the event of a thermal event.

[0106] To close these recesses for electrical insulation during normal operation, a thermal protective layer 218 of the thermal protection arrangement 217 is arranged on the cell support structures 12 (either as shown for each recess separately or as a larger unit for several or all recesses together), in particular glued in place as shown here.

[0107] In addition to the design according to the embodiment from Fig. 10 are in the embodiment according to Fig. Eleven additional thermal protection layers 218A.3 or 218B.3 and 218B.4 were arranged, in particular glued on as shown here.

[0108] While the also according to the embodiment from Fig. While the thermal protection layers 218A.3 and 218B.4 are arranged on the side of the cell carrier structure 12A and 12B facing the cells, respectively, thermal protection layers 218A.3, 218B.3, and 218B.4 are arranged on the side of the cell carrier structure 12A and 12B facing away from the cells. In this way, the cell carrier structures 12 themselves can also be insulated from excessive exposure to heat, particles, and electrical potential by the thermal protection layers 218A.3, 218B.3, and 218B.4 of the thermal protection arrangements 217A and 217B.

[0109] In the illustrated embodiment, the thermal protective layers 218 are made with or from mica.

[0110] In the event of a thermal event affecting cell 10B.1 of cell layer B – represented here by the flame T_BA – the thermal protection layer 218B.2 fails due to the high pressure applied in the normal direction. As a result, the hot gases and electrically conductive particles propagate through and over time within the degassing channel 14_AB, impacting the cell support structure 12A and the thermal protection layers 218A.3, 218A.1, and 218A.2. Through a combination of pressure reduction caused by the distribution of the gases and particles within the degassing channel 14_AB and the high thermal and electrical insulation capacity of the thermal protection layers 218A.1 and 218A.2, the cells 10A of cell layer A, as well as the cell support structure 12A, are decoupled from the effects of the thermal event – ​​preventing both propagation and an unwanted short circuit.

[0111] Fig. Figure 12 shows a thermal protection arrangement 317 for the high-voltage storage device 2 according to a third exemplary embodiment.

[0112] The thermal protection arrangement 317 is – unlike the protection arrangements 117 and 217 from the Fig. 10 and Fig. 11 - not divided into a protective arrangement assigned to the cell carrier structure 12A of cell layer A on the one hand and a protective arrangement assigned to the cell carrier structure 12B of cell layer B on the other.

[0113] Instead, the tent support structures 12 A and 12 B are firmly connected to each other via a protective layer support 319. The protective layer support 319 is designed to not impede the propagation of hot particles and gas in the degassing channel 14_AB, but still to support an arrangement of several layers of thermal protective layers 318.

[0114] The unimpeded spread of hot particles and gas is made possible by the fact that the protective layer carrier 319 has a honeycomb structure, but the honeycomb walls have large recesses.

[0115] Furthermore, the protective layer support 319 has support walls 320 against the cell support structures 12A and 12B, as well as connecting walls 321 between these support walls. The large recesses are arranged on the connecting walls 321.

[0116] To compare the thermal and electrostatic insulation effect between cell layers A and B (with the solutions from Fig. 10 or Fig. 11) To further improve the support walls 320 and the connecting walls 321, the support walls 320 and the connecting walls 321 are lined with additional thermal protection layers 318A.6 and 318B.6 (here in particular, they are covered with them).

[0117] In the illustrated embodiment, from a functional perspective, all thermal protection layers 318A.1, 318A.2, 318A.3, 318B.2, 318B.3, 318B.4 are also present.

[0118] The thermal protection layers 318A.6, 318B.6 and 318A.1, 318A.2, 318A.3, 318B.2, 318B.3, 318B.4 are arranged in such a way that, in the event of a thermal event, four thermal protection layers would have to be breached on any possible venting path in order to affect an opposing cell in a thermally or electrostatically relevant way.

[0119] This results in further improved protection against propagation.

[0120] Fig. Figure 13 shows a section of the high-voltage storage unit 2' from Fig. 6 with a serial connection 24_DC, 24_CB, 24_BA of the individual cell layers A, B, C, D to each other, in a cut side view.

[0121] The individual cell layers are equipped with battery cells 10 in such a way that, for example, a potential difference of approximately 600V results at the two degassing channels 14_AB and 14_CD.

[0122] The cell layer interconnection is implemented in a known manner in that an interruption of the current flow can only occur towards one of the poles HV- or HV+, and not between the individual cell layers. For this purpose, a disconnect switch 22- is arranged at the negative pole HV- and a disconnect switch 22+ is arranged at the positive pole HV+, in a manner known per se.

[0123] The disconnect switches 22 can be configured in various known ways, for example as active or passive disconnect elements. A passive disconnect element, in this context, is understood to mean in particular that the disconnect element interrupts the current flow when a limit current flow is exceeded. For this purpose, a known fuse arrangement can be used, for example. An active disconnect element, in this context, is understood to mean in particular that the disconnect element interrupts the current flow, for example, depending on the detection of a thermal event, and in particular is activated by a control unit.

[0124] In the event of a fault (especially due to particle ingress, for example, triggered by particle contamination during cell production), a battery cell (here 10C) can experience thermal runaway during vehicle operation. The internal gas formation and the resulting internal pressure cause the cell's internal vent to open. This can lead to the expulsion of hot gas and the ejection of potentially conductive particles.

[0125] This ejection can lead to uncontrollable subsequent reactions in the high-voltage storage unit 2', in particular through secondary short circuits K due to bridging of the air and creepage distances (LuK). This is promoted by the contact of the particles P with the potential-carrying vents of the opposite cells (here 10D). Depending on the wiring configuration, a short circuit can occur across a potential difference of several hundred volts, in the described embodiment of approximately 600 V.

[0126] In other words, the presence of particles P in the degassing channel 14_CD causes the airflow (LuK) that would be sufficient without particles P to no longer be enough to prevent a short circuit due to the potential difference of approximately 600 V between the two cell layers D and C separated by the degassing channel 14_CD.

[0127] The short-circuit circuit can only be interrupted outside the series connection of the cell layers by means of the disconnect switch 22- at the negative terminal HV- and / or the disconnect switch 22+ at the positive terminal HV+. This interruption is triggered, for example, by a current detection device, another suitable short-circuit detection device, and / or by the active activation of a pyrolytic fuse based on fire detection / cell failure detection. However, this means that even after the disconnection, a high potential remains at the short-circuit point in the event of a short circuit.

[0128] In the Fig. 14 and Fig. 15 are two further different exemplary design variants of the high-voltage storage unit 2' made of Fig. Six methods have been shown that can be used to reduce the existing potential more quickly and reliably.

[0129] Fig. Figure 14 shows a section of the high-voltage storage unit 2' from Fig. 6 with a serial connection 24_DC, 24_CB, 24_BA of the individual cell layers A, B, C, D to each other according to a first exemplary design variant, in a cut side view.

[0130] From the execution variant according to Fig. 13 differs in Fig. Figure 14 shows that this is achieved essentially by providing additional separating elements 22_BA, 22_CB and 22_DC. The separating element 22_BA is configured to separate the serial connection 24_BA between cell layer A and cell layer B; the separating element 22_CB is configured to separate the serial connection 24_CB between cell layer B and cell layer C; the separating element 22_DC is configured to separate the serial connection 24_DC between cell layer C and cell layer D.

[0131] The short-circuit circuit can be separated by means of the additional active or passive separating elements 22_BA, 22_CB and 22_DC introduced in the current path of the serially connected cell layers A, B, C and D.

[0132] The three additional separating elements 22_BA, 22_CB and 22_DC enable a more precise separation of built-up potential at or around the affected degassing channel 14_CD.

[0133] Fig. Figure 15 shows a section of the high-voltage storage unit 2' from Fig. 6 with a serial interconnection 24_DB, 24_BC, 24_CA of the individual cell layers A, B, C, D to each other according to a second exemplary design variant, in a cut side view.

[0134] Of the design variants according to the Fig. 13 or Fig. 14 differs from the Fig. 15 shown essentially by a modified serial interconnection of the cell layers A, B, C, D to each other.

[0135] In the version of the Fig. 15 serial interconnections were performed in the order D before B before C before A with the corresponding serial shadows serial interconnection 24_DB, 24_BC, 24_CA.

[0136] This serial connection makes it possible to achieve a precise separation of built-up potential at each of the degassing channels 14_CD and 14_AB with only a single fuel element 22_BC arranged between the cell layers.

[0137] Fig. 16 shows the high-voltage storage unit Fig. 2 without the housing pot in a perspective oblique view.

[0138] The cell layer D is visibly arranged on a ZKS holder plate 26_D. The ZKS holder plate 26_D itself is fixed in the X and Y directions by positive locking (in particular by means of projections provided for this purpose, cf. reference numeral 27 on the ZKS holder plate 26_A) and in the Z direction by gravity (optionally additionally by screws) on the lower housing cover 6.2. In the exemplary embodiment, the housing cover 6.2 itself is designed as a shear panel.

[0139] With respect to the vehicle's vertical direction Z above cell layer D, cell layers C, B, and A are arranged in this order. All cell layers are arranged with battery cells 10, particularly in a hexagonal packing, such that the width of the individual cell layers in the vehicle's transverse direction Y is smaller at the rear end of the high-voltage storage system 2 than at the front end.

[0140] As especially regarding the Fig. As described in detail in 2-6, each cell layer C, B, or A positioned higher up is located half a distance s of the longitudinal axes of adjacent battery cells further back with respect to the vehicle's longitudinal direction X than the cell layer D, C, or B located lower down. This allows for the formation of the cell layer inclined at angle alpha. Fig. 16 housing pots not shown 6.1.

[0141] The ZKS holder plates 26_C and 26_B for the cell layers C and B respectively are arranged back to back, being fixed to each other at the common contact surface by positive locking and gravity (if necessary additionally by screws).

[0142] The upper cell layer A has a Z KS holder plate 26_A. This is secured to the upper base of the housing pot 6.1 by positive locking and, if necessary, additionally by screws.

[0143] As already detailed in previous figures, the vents of battery cells 10A of cell layer A and 10B of cell layer B open together into a degassing channel 14_AB; the vents of battery cells 10C of cell layer C and 10D of cell layer D open together into a degassing channel 14_CD. The two degassing channels are located inside the cell support structure 12_AB and 12_CD, respectively, and extend essentially in the longitudinal and transverse directions analogously to the extent of cell layers A and B and C and D, respectively (and also cover the longitudinal offset of the cell layers with regard to the arrangement of the vents).

[0144] In Fig. 16 now shows the degassing collection channel 30, by means of which the degassing channels 14_AB and / or 14_CD can be vented into the environment in the event of a thermal event.

[0145] Fig. Figure 17 shows in detail the venting path from both degassing channels 14 to an expansion valve 32, the outer side of which is connected to a venting channel to and through the slot, the degassing opening 7, located in the housing cover 6.2 below the expansion valve 32.

[0146] The cell support structures 12, which each define and seal a degassing channel 14 to the outside, each have an opening towards the degassing collection channel 30 which is tightly sealed with this gas, through which hot gases and particles can be discharged to the expansion valve 32, especially under high gas pressure.

[0147] Fig. Figure 18 shows, from a cutaway perspective from above, the transition from the degassing channel 14_AB to the degassing collection channel 30, as well as the opening provided for this purpose in the cell carrier structure 12_AB.

[0148] Fig. Figure 19 shows, from a cutaway perspective from the front, the venting path V (dashed lines) which the hot gases and particles from a thermal event may take from the degassing channel 14_AB or 14_CD, then through the degassing collection channel 30, then through the expansion valve 32, then through the degassing opening 7, to be discharged from the high-voltage storage into the environment.

[0149] Fig. Figure 20 illustrates the frictional connections in the high-voltage storage unit 2 with respect to the different spatial directions, wherein the frictional connections are such that in all intended operating states the high-voltage storage unit 2 is fixed in the vehicle and the cell layers A, B, C and D are fixed in the high-voltage storage unit 2.

[0150] With regard to the longitudinal direction X and the transverse direction Y of the vehicle, the cell positions within the housing are determined by positive locking, by providing projections 27 and partially recesses 28 on the ZKS holder plates 26.

[0151] For example, in Fig. Figure 20 shows the projections 27_A of the ZKS holder plate 27_A, which are received by corresponding recesses in the housing pot 6.1.

[0152] The projections 27_B and 27_C of the ZKS holder plates 26_B and 26_C are also shown as examples, which are arranged and shaped in such a way that they interlock positively in the transverse direction Y and longitudinal direction X of the vehicle.

[0153] The projections 27_D of the ZKS holder plate 26_D are also shown as an example; they are shaped in such a way that they engage in recesses 29 of the housing cover 6.2 and are thus positively locked to the housing cover in the transverse direction Y and longitudinal direction X of the vehicle.

[0154] Fig. Figure 21 illustrates an example of a possible design of the ZKS holder plate 26_C, which is designed with projections 27_C and recesses 28_C, which are designed to engage with corresponding projections and recesses on the resting ZKS holder plate 26_B, forming a positive fit with respect to the longitudinal direction X of the vehicle and the transverse direction Y of the vehicle.

[0155] Overall, the exemplary high-voltage storage system 2 is shown in the figures according to Fig. 2 with various inventive facets. Each of the described inventive facets can, in principle, be combined arbitrarily with any other inventive facet, but can also be implemented individually in the high-voltage storage device 2 or another high-voltage storage device according to the invention, independently of the other facets. REFERENCE MARK LIST 1* Famous supercar 2* Known high-voltage storage 4* Known location 1 Supercar 2 high-voltage storage units (example according to Fig. 2) 2' high-voltage storage (example according to Fig. 6) 4-seater 5 backrest 6 Housings (Example according to Fig. 2) 6.1 Housing pot (Example according to Fig. 2) 6.2 Lower housing cover (designed as a sliding panel) 7 Degassing opening in the lower housing cover 6' housing (example according to Fig. 6) 8 Coolant connection 9 Housing screw 10, 10A, 10B, 10C, 10D battery cells 12 Cell support structure 14, 14_AB, 14_CD Degassing channel 16, 16_A, 16_BC, 16_D Cell contacting system 17 Thermal protection arrangement (Example according to Fig. 9) 18 Thermal protective layer (Example according to Fig. 9) 20 cell casings 22-, 22+ Disconnect switch outside cell layer interconnections 22_DC, 22_CB, 22_BA Disconnect switch between cell layers (Example according to Fig. 14) 22_BC Disconnect switch between cell layers (example according to Fig. 15) 24_DC, 24_CB, 24_BA cell layer interconnection (example according to Fig. 14) 24_DB, 24_BC, 24_CA Cell layer interconnection (Example according to Fig. 15) 26_A, 26_B, 26_C, 26_D ZKS mounting plate 27 protrusions in a ZKS mounting plate 28 recesses in a ZKS mounting plate 29 Recess from the housing cover 30 Entaasunassammelkanal 32 Expansion valve 34 prestressing elements 117 Thermal protection arrangement (Example according to Fig. 10) 118 Thermal protective layer (Example according to Fig. 10) 217 Thermal protection arrangement (Example according to Fig. 11) 218 Thermal protective layer (Example according to Fig. 11) 317 Thermal protection arrangement (example according to Fig. 12) 318 Thermal protective layer (Example according to Fig. 12) 319 Protective layer carriers (example according to Fig. 12) 320 retaining walls (example according to Fig. 12) 321 Connecting walls (Example according to Fig. 12) alpha Tilt angle of the HVS to the vehicle YZ plane A, B, C, D cell layers HV-, HV+ poles of the high-voltage battery K Short circuit (represented as a star) P particles (represented as small crosses) s distance T, T_AB, T_BA, T_CD Thermal event (represented as flame) V Venting route (dashed lines in Fig. 19) x Longitudinal extent (e.g. according to Fig. 2) x' Longitudinal extent (Example according to Fig. 6) X Vehicle longitudinal direction Y Vehicle transverse direction Z Vehicle lifting direction

Claims

[1] High-voltage storage device (2, 2') for arrangement in an electrically propelled motor vehicle (1), comprising at least two superimposed cell layers (A, B, C, D) each with a plurality of cylindrical battery cells (10) having a vent end face and a pole end face, characterized by , that the vent end faces of the battery cells of two adjacent cell layers are arranged in a mutually aligned manner. [2] High-voltage storage device (2, 2') according to claim 1, characterized by , that a degassing channel (14, 14_AB, 14_CD) is arranged between the two adjacent cell layers. [3] High-voltage storage device (2, 2') according to any one of the preceding claims, characterized by , that between at least one of the two adjacent cell layers of a cell layer of the high-voltage storage arranged on the pole end face a cell contacting system is formed, with which the battery cells of these two cell layers are contacted. [4] High-voltage storage device (2, 2') according to claim 3, characterized by , that the cell contacting system is designed for the joint contacting of the cells of both adjacent cell layers. [5] High-voltage storage device (2, 2') according to any one of the preceding claims, characterized by , that the longitudinal axes of the battery cells of the two adjacent cell layers are arranged offset from each other. [6] High-voltage storage device (2, 2') according to any one of the preceding claims, characterized by , that the longitudinal axes of the battery cells of the two adjacent cell layers are arranged such that a center of a degassing flame (T, T_AB, T_BA, T_CD) primarily impacts between the battery cells of the adjacent cell layer. [7] High-voltage storage device (2, 2') according to any one of the preceding claims, characterized by , that the vent axes of one of the two adjacent cell layers are maximally offset from the vent axes of the other of the two adjacent cell layers.

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