Traction battery for a motor vehicle, method for producing a traction battery and motor vehicle

Abstract

The invention relates to a traction battery (10) for a motor vehicle, comprising a housing comprising an upper housing part (14) and a lower housing part (12), which housing delimits a receiving space (16) in which at least one battery module is received, wherein the battery module comprises a cell carrier (18) by means of which a plurality of battery cells (22) of the traction battery (10) are held, wherein the cell carrier (18) is held both on the upper housing part (14) and on the lower housing part (12) via at least one screw connection (28).

Description

[0001] The invention relates to a traction battery for a motor vehicle, a method for producing a traction battery for a motor vehicle and a motor vehicle with a traction battery.

[0002] From DE 10 2021 128 304 A1 a battery is known, comprising a housing with a cell receiving space in which a cell carrier and a plurality of battery cells held thereby are arranged.

[0003] The object of the present invention is to provide a solution which enables a particularly simple production of a particularly stable traction battery.

[0004] This object is achieved according to the invention by the subject matter of the independent claims. Further possible embodiments of the invention are disclosed in the subclaims, the description, and the figures. Features, advantages, and possible embodiments presented in the description for one of the subject matter of the independent claims are to be regarded at least analogously as features, advantages, and possible embodiments of the respective subject matter of the other independent claims, as well as any possible combination of the subject matter of the independent claims, optionally in conjunction with one or more of the subclaims.

[0005] The invention relates to a traction battery for a motor vehicle, in particular a motor vehicle, in particular a passenger car. The traction battery is designed to provide electrical energy for an electric drive train of the motor vehicle. This means that the motor vehicle can be driven by means of electrical energy from the traction battery. The traction battery is in particular a so-called high-voltage storage device. The traction battery comprises a housing which has an upper housing part and a lower housing part. The housing delimits a receiving space. In particular, this receiving space is delimited in the installed position by the upper housing part upwards along the vertical direction of the vehicle and by the lower housing part downwards along the vertical direction of the motor vehicle. At least one battery module is arranged in this receiving space.This battery module comprises a cell carrier, by means of which a plurality of battery cells of the traction battery are held. In particular, the respective battery cells are designed as respective round cells, which are arranged next to one another with their respective central axes parallel to one another. The cell carrier is designed to fix the battery cells in their position relative to one another. In particular, the cell carrier encloses the round cells at least in a vertical section along the central axis over their entire circumference. As a result, the round cells are positioned particularly securely and precisely relative to one another by means of the cell carrier. In the traction battery, it is provided that the cell carrier is held by at least one screw connection both to the upper housing part and to the lower housing part.It is thus possible to access the at least one battery module arranged in the receiving space by loosening the at least one screw connection, thereby allowing the battery module or individual battery cells of the battery module to be replaced particularly easily. Furthermore, the cell carrier can be connected to the housing via the at least one screw connection in a particularly cost-effective, simple, precise, and secure manner, in particular by positioning and securing it within the housing.

[0006] The cell carrier can in particular have a passage for each battery cell, into which the associated battery cell is inserted in the battery module. When inserted into the respective passage, a gap can be kept free between a respective outer wall, in particular a lateral surface of the respective battery cell, and a wall of the cell carrier delimiting the passage. A temperature control fluid can flow through this gap for direct cooling of the respective battery cell. This means that the temperature control fluid flowing through the gap flows directly along the outer surface, in particular the lateral surface of the respective battery cell, whereby this battery cell can be temperature controlled. The temperature control fluid is in particular a cooling fluid which is designed to absorb heat from the battery cell, whereby the battery cell is cooled.Alternatively, the temperature control fluid can be a heating fluid which is designed to transfer heat to the respective battery cell, thereby heating the battery cell.

[0007] In addition to the battery cells, the traction battery can include electrical connections and supply lines. Batteries can be used in stationary or mobile applications, particularly in automotive applications. Automotive applications place high demands on storage density and, in particular, power density. High electrical power outputs occur, for example, during high-load driving or during rapid battery charging with high charging powers of typically 50 kW to 500 kW in an electric vehicle. Traction batteries are often actively cooled.In this case, cooling of the battery cells of traction batteries can be achieved not only with cooling plates in thermal contact with the battery cells and with single-phase coolants, such as water / glycol mixtures, or with two-phase refrigerants, such as R1234YF, but alternatively or additionally directly using a high-dielectric fluid, which primarily flows in a single-phase manner directly around the walls of the battery cells. In the described immersion cooling of the traction battery, in which the temperature control fluid flows directly around the battery cells, no cooling plates or evaporators are provided, but rather, there is a fluid circulation circuit for the temperature control fluid within the traction battery.In the described traction battery with immersion cooling, the mechanical structural connection of the battery cells, which in this case are vertical round cells, takes place within the cell carrier. Within this, the battery cells are fixed, forming a surrounding flow channel, which is the gap, in such a way that an internal battery structure is created that allows the temperature control fluid to flow around the battery cells. This structure is then enclosed by the housing.

[0008] It is already known to implement a mechanical connection of cell carrier structures, cell modules, or cell groups, both internally (i.e., between battery cells and cell carriers), and to the battery housing by means of structural bonding. For example, the battery cells are firmly bonded to one another to form a structural composite. For example, cell assemblies or cell carriers, in which the battery cells are mechanically fixed, can each be bonded to a portion of an inner wall of a housing structure, thus forming a larger structural composite. Intermediate components can be used that simultaneously bear against the cell carriers and an inner wall of the housing, each forming a contact surface suitable for bonding.

[0009] In contrast to such glued batteries, the traction battery, in which the cell carrier is held to both the upper and lower housing parts via at least one screw connection, is particularly lightweight and can be manufactured particularly cost-effectively because no adhesive, which is often expensive, is required. Furthermore, in contrast to a glued battery, the described traction battery can be manufactured particularly easily and quickly because no curing times for the adhesives need to be taken into account. As a result, the assembly hall space required for the manufacturing process of the traction battery is particularly low compared to a glued battery. Furthermore, no volatile solvents are produced during the screw connection, which would require special occupational safety measures. Furthermore, the traction battery has particularly good tensile strength due to the at least one screw connection.In contrast, adhesive joints tend to peel upon failure. Therefore, adhesive joints subject to high tensile loads are systematically unsuitable for the use of adhesive joints, as adhesive joints can lead to unstable failure behavior, particularly through peeling, if the load is applied asymmetrically. The at least one screw connection also enables easy replacement of defective battery cells and, as a result, particularly simple repair. Furthermore, due to the at least one screw connection, which can be removed particularly easily and non-destructively, the traction battery enables particularly simple and extensive material recycling, as the components of the traction battery can be separated from one another particularly easily, making it particularly easy to disassemble the traction battery. Adhesive bonding would prevent this fragmentation of the traction battery or at least make it more difficult.

[0010] In the described traction battery, the structural connection between the lower housing part and the upper housing part and / or the cell carrier is established by a direct screw connection using the at least one screw connection. In particular, the lower housing part and the upper housing part are screwed together not only in a circumferential edge region but in particular in an area with respect to the vehicle's vertical direction in the installation position above or below the at least one cell carrier. The at least one cell carrier is clamped between the lower housing part and the upper housing part by means of the at least one screw connection. Alternatively, the lower housing part can be screwed separately into the cell carrier and the cell carrier can be screwed separately to the upper housing part.

[0011] In a possible development of the invention, it is provided that the upper housing part is screwed to the lower housing part by means of the at least one screw connection, whereby the cell carrier is clamped between the upper housing part and the lower housing part. In this case, a screw element of the screw connection extends through the cell carrier. In particular, the cell carrier has an opening through which the screw element is inserted. This opening is arranged in particular between respective battery cells held by the cell carrier, whereby the screw element is inserted laterally between at least two battery cells of the cell carrier.If the upper housing section is clamped directly to the lower housing section via respective screw connections, the components of the traction battery can be held together with a particularly small number of screw connections, in particular the cell carrier can be fixed in its position within the receiving space. Because the screw element in the at least one screw connection extends through the opening of the cell carrier in a direction that runs parallel to a longitudinal direction of the center axis of the respective battery cells, and is also referred to below as the axial direction, the cell carrier is particularly well protected against lateral slippage within the receiving space in a direction perpendicular to the axial direction.

[0012] In an alternative possible embodiment of the invention, it is provided that the cell carrier is screwed to the upper housing part via at least one first screw connection and to the lower housing part via at least one second screw connection. In other words, the cell carrier is screwed separately to the lower housing part and the upper housing part. In particular, the cell carrier can be screwed successively first to one of the housing parts and then to the other housing part. This allows for a separate, particularly precise positioning of the cell carrier relative to the respective housing parts.

[0013] In this context, it can be provided in particular that a screw receptacle with a first thread is provided on the upper housing part or on the lower housing part, which can be brought into engagement with a second thread of the screw element to form the screw connection. In this case, the screw receptacle is at least partially inserted into an opening in the cell carrier. Thus, the screw receptacle, which is fastened to the upper housing part or to the lower housing part and is inserted into the opening in the cell carrier, can already achieve positioning of the cell carrier relative to the housing or secure the cell carrier against lateral slipping within the receiving space. The first thread and the second thread are thus designed as a thread and a corresponding counter thread. The screw connection is thus produced by bringing the first thread into engagement with the second thread.In particular, one of the threads is designed as an internal thread and the other as an external thread. Depending on whether the cell carrier is screwed to one of the housing parts via the at least one screw connection or the housing parts are screwed together via the at least one screw connection, a screw head of the screw element can be applied to the cell carrier or to one of the housing parts on a side facing away from the screw receptacle. By screwing the second thread of the screw element into the first thread of the screw receptacle, the cell carrier can be clamped to one of the housing parts or the housing parts can be clamped to one another.

[0014] In a further possible embodiment of the invention, the screw receptacle for centering the cell carrier in the housing rests, at least in some areas, without play against a wall of the cell carrier that defines the opening. This means that the screw receptacle rests circumferentially against the wall of the cell carrier that defines the opening. In particular, there is a press fit between the screw receptacle and the cell carrier. As a result, the cell carrier is positioned particularly precisely in the receiving space by means of the screw receptacle relative to the housing part to which the screw receptacle is attached.

[0015] In a further possible embodiment of the invention, the screw receptacle has a radially projecting collar which, around its entire outer circumference, rests against the wall of the carrier delimiting the opening without play. The collar thus protrudes laterally from the screw receptacle perpendicular to the axial direction. This makes it possible for the cell carrier to rest against the screw receptacle only in the region of the collar and to be centered relative to the housing part to which the screw receptacle is fastened via this collar. Further regions of the screw receptacle that are different from the collar can thus be designed to be at least substantially contact-free with the cell carrier.

[0016] In a further possible embodiment of the invention, it is provided that the screw receptacle is sleeve-shaped and has a deformation region. For example, it can be provided that the cell carrier precisely does not touch the screw receptacle in this deformation region and is thus arranged without contact with the deformation region of the screw receptacle. The deformation region is formed by a longitudinal section of the screw receptacle running in the axial direction, in which the screw receptacle has a wave-shaped wall. As a result, the screw receptacle is configured such that it deforms in the deformation region along the axial direction before another region of the screw receptacle is deformed in this axial direction.The axial direction runs parallel to a screw-in direction in which the threads of the screw receptacle and the screw element, and thus the second thread of the screw element and the first thread of the screw receptacle, are inserted into one another. The deformation area of ​​the screw receptacle enables the screw receptacle to be compressed or pulled apart in the axial direction in the length section over which the deformation area extends. This allows tolerances of the traction battery or temperature-related size changes in the axial direction to be compensated particularly well in the screw connection by pulling the screw receptacle apart or pressing it together in the axial direction in the deformation area, depending on the tolerance to be compensated for.

[0017] In a further possible embodiment of the invention, the screw receptacle is glued to the lower housing part or to the upper housing part. In this case, the screw receptacle is glued to the respective housing part, particularly on a side facing the cell carrier. By gluing the screw receptacle to the respective housing part, the screw receptacle can be held particularly securely to the housing part and attached to the housing part particularly easily.

[0018] The invention further relates to a method for producing a traction battery for a motor vehicle. The method provides for at least one battery module to be accommodated in a receiving space defined by a housing of the traction battery. This housing comprises an upper housing part and a lower housing part. The battery module comprises a cell carrier, by means of which a plurality of battery cells of the traction battery are held. The method provides for the cell carrier to be fastened to both the upper housing part and the lower housing part via at least one screw connection.In this case, it can be provided that the upper housing part is screwed to the lower housing part by means of the at least one screw connection, wherein the cell carrier is clamped between the housing parts by a screw element for establishing the screw connection being pushed through the cell carrier, in particular through an opening in the cell carrier in the axial direction. Alternatively, the cell carrier can be screwed separately to the lower housing part via at least one first screw connection and to the upper housing part via at least one second screw connection. In particular, within the scope of the method, a traction battery is produced, as has already been described in connection with the traction battery according to the invention. Within the scope of the method, the traction battery can be produced particularly easily.

[0019] The invention further relates to a motor vehicle with a traction battery as already described in connection with the traction battery according to the invention. The traction battery is intended to provide electrical energy for an electric drive train of the motor vehicle, whereby the motor vehicle can be electrically driven.

[0020] Further features of the invention may emerge from the claims, the figures, and the description of the figures. The features and combinations of features mentioned above in the description, as well as the features and combinations of features shown below in the description of the figures and / or in the figures alone, can be used not only in the respective combinations specified, but also in other combinations or on their own, without departing from the scope of the invention.

[0021] The drawing shows in: Fig. 1 is a schematic perspective view of a section of a traction battery for a motor vehicle; Fig. 2 a schematic sectional view of the traction battery section; Fig. 3 an enlarged section of the sectional view according to Fig. 2; Fig. 4 a schematic side view of a screw receptacle in a first embodiment; Fig. 5 a schematic side view of the screw receptacle in an alternative, second embodiment; and Fig. 6 a schematic side view of a screw element.

[0022] In the figures, identical and functionally identical elements are provided with the same reference symbols.

[0023] In the Fig. 1 and Fig. 2 shows a traction battery 10 for a motor vehicle in different views. In Fig. 1 is the traction battery 10 in a partially sectioned schematic perspective view and in Fig. 2 in a sectional view. The traction battery 10 comprises a housing, which in this case consists of a lower housing part 12 and an upper housing part 14. The upper housing part 14 and / or the lower housing part 12 are made of a solid material. In particular, the upper housing part 14 and / or the lower housing part 12 can be made of steel and / or aluminum and / or a fiber-reinforced plastic. The lower housing part 12 and the upper housing part 14 are each plate-shaped and together delimit a receiving space 16. In this case, the lower housing part 12 and the upper housing part 14 delimit a receiving space 16 upwards and downwards along an axial direction A. The traction battery 10 further comprises a cell carrier 18, which has a plurality of passages 20. In this case, a battery cell 22 designed as a round cell is inserted into each passage 20.The cell carrier 18 is thus configured to position the battery cells 22. In this case, the cell carrier 18 encloses all battery cells 22 around their entire circumference, extending in the axial direction A. This means that the battery cells 22 are completely enclosed laterally by the cell carrier 18.

[0024] In the respective passages 20, respective lateral surfaces of the battery cells 22 can be arranged laterally spaced from a wall of the cell carrier 18 delimiting the respective passage 20, whereby respective gaps are kept free between the battery cells 22 and the walls of the cell carrier 18 delimiting the respective passages 20. A temperature control fluid can be guided through these gaps, whereby the battery cells 22 can be directly temperature-controlled, in particular heated or cooled, by the temperature control fluid flowing around them. In order to enable the temperature control fluid to be supplied to these gaps or the cooling fluid to be removed from the gaps, the traction battery 10 in the present case comprises respective fluid guides 24, one of which is arranged above the cell carrier 18 and the other below the cell carrier 18 with respect to the axial direction A. The respective fluid guides 24 are designed as plate-shaped flow grids.

[0025] In the present case, the traction battery 10 additionally comprises a cell contact system 26, which in this case is arranged above the cell carrier 18 with respect to the axial direction A and is configured to interconnect the battery cells 22. For this purpose, the cell contact system 26 is electrically contacted with all battery cells 22. To ensure that all of the aforementioned components in the traction battery 10 can be securely positioned and fixed relative to one another, it is provided that the cell carrier 18 is held to the lower housing part 12 and to the upper housing part 14 via at least one screw connection 28. In the present case, the lower housing part 12 and the upper housing part 14 are connected to one another via a plurality of screw connections 28, whereby the cell carrier 18 is clamped between the lower housing part 12 and the upper housing part 14.In other words, the lower housing part 12 is screwed to the upper housing part 14 via the plurality of screw connections 28, wherein screw elements 30 of the respective screw connections 28 extend in the axial direction A through the cell carrier 18, in particular through respective openings 32 of the cell carrier 18. At least one of the screw connections 28 runs centrally between respective battery cells 22. This means that the upper housing part 14 and the lower housing part 12 are screwed to one another not only in an edge region of the traction battery 10 but also in a central region and thus between respective battery cells 22. In . Fig. 2 it can be seen particularly well how the respective screw connections 28 extend centrally through the cell carrier 18 in the axial direction A.

[0026] In Fig. 2, the layered structure of the traction battery 10 along the axial direction A can be seen particularly well. At the very bottom, the traction battery 10 has the lower housing part 12. A first of the fluid guides 24 is arranged on the lower housing part 12. The cell carrier 18 with the battery cells 22 is arranged above the first fluid guide 24. The cell contact system 26, on which the second fluid guide 24 rests, is arranged above the battery cells 22. The second fluid guide 24 is covered at the top by the upper housing part 14. The respective screw connections 28 are formed by respective screw elements 30 and by respective screw receptacles 34.

[0027] In the Fig. 4 and Fig. 5 shows respective screw receptacles 34 in different embodiments in schematic side views. In Fig. 6, the screw element 30 is shown in a schematic side view. As in Fig. 2, the screw element 30 has a second thread designed as an external thread, which can be brought into engagement with a first thread designed as an internal thread of the associated screw receptacle 34 for establishing the screw connection 28. This means that the screw element 30 is partially screwed into the screw receptacle 34 for establishing the screw connection 28. As further shown in Fig. 2, in the present case the screw receptacle 34 is placed on the lower housing part 12 with respect to the axial direction A above the lower housing part 12, in particular glued to the lower housing part 12. The screw receptacle 34 extends in the axial direction A through a through-opening 36 of the first fluid guide 24 into the opening 32 of the cell carrier 18. The screw receptacle 34 can have a play with respect to the through-opening 36. In the present case, it is provided that the screw receptacle 34 centers and positions the cell carrier 18 relative to the lower housing part 12 and fixes it with respect to directions of movement running perpendicular to the axial direction A. For this purpose, it is provided that the screw receptacle 34 is arranged in the opening 32 of the cell carrier 18 without play, at least in a longitudinal region along the axial direction A.

[0028] The screw receptacle 34 is in the Fig. 4 and Fig. 5 in different designs. In each of the embodiments, the screw receptacle 34 has a plate element 37 which is plate-shaped and via which the screw receptacle 34 can be glued to the housing base 12 over a particularly large area. A screw-in sleeve 38 protrudes from the plate element 37 in the axial direction A. This screw-in sleeve 38 is sleeve-shaped, and the screw element 30 can be screwed into the screw-in sleeve 38 to create the screw connection 28. In the present case, the screw-in sleeve 38 has a deformation region 40 in each of the two embodiments shown. In this deformation region 40, the screw-in sleeve 38 has a wave-shaped wall. This means that the screw-in sleeve 38 is designed in the deformation region 40 like a corrugated pipe or a corrugated hose with a wave-shaped, changing diameter.Due to this corrugation, the screw-in sleeve 38 is compressible and expandable in the deformation region 40 with respect to the axial direction A. It can be provided that the screw-in sleeve 38 is designed to be bendable in the deformation region 40 and thus bendable in a direction running perpendicular to the axial direction A. The screw receptacle 34 is thus deformed when a force is applied in the deformation region 40 along the axial direction A, before a further region of the screw receptacle 34 is deformed in this axial direction A. In the present case, the axial direction A runs parallel to a screw-in direction in which the threads of the screw receptacle 34 and the screw element 30 are inserted into one another in order to produce the screw connection 28.

[0029] The screw receptacle 34 can - as in Fig. 5 - with a radially projecting collar 42 or - as in Fig. 4 - be designed without this radially projecting collar 42. The radially projecting collar 42 is designed to be applied circumferentially without play to the wall of the cell carrier 18 delimiting the opening 32, whereby the cell carrier 18 can be reliably centered and positioned relative to the housing lower part 12 by means of the screw receptacle 34 glued to the housing lower part 12 via the play-free fitting of the screw receptacle 34 into the opening 32 of the cell carrier 18.

[0030] In Fig. 6 shows the screw element 30, wherein it can be seen that the screw element 30 in this case has a shaft 44 which is intended to be inserted into the opening 32 of the cell carrier 18. At one end, a screw head 46 adjoins the shaft 44. At the other end, a threaded tube piece 48 adjoins the shaft 44 and is designed to be inserted into the screw-in sleeve 38 of the screw receptacle 34. The threaded tube piece 48 has the second thread designed as an external thread, which can be brought into engagement with the first thread designed as an internal thread of the screw receptacle 34 to produce the screw connection 28. In the present case, the screw element 30 is formed in one piece from steel. Alternatively, the screw element 30 can be made of aluminum, in particular high-strength aluminum, or a plastic composite material.Alternatively, the screw head 46, the shaft 44 and the threaded sleeve 48 can be manufactured separately and then connected together.

[0031] In Fig.3 shows an enlarged view of a screw connection receptacle 50 on the upper housing part 14. This screw connection receptacle 50 is designed as a recess in the upper housing part 14. The screw head 46 is inserted into this screw connection receptacle 50. In particular, the screw connection receptacle 50 is selected to be deep enough that the screw head 46 can be countersunk into the screw connection receptacle 50, thereby preventing the screw head 46 from projecting beyond an upper edge of the upper housing part 14 in the axial direction A. The screw head 46 can be sealed off from the upper housing part 14 by means of a fluid seal 52. The shaft 44 of the screw element 30 is thus inserted through an opening in the upper housing part 14 and through an opening in the second fluid guide 24 into the opening 32 of the cell carrier 18.To prevent the temperature control fluid from escaping from the traction battery 10 through the opening in the upper housing part 14 or to prevent fluid, for example water, from entering the traction battery 10 through the opening in the upper housing part 14, the fluid seal 52 is provided, which seals the screw head 46 to the upper housing part 14. This means that the opening in the upper housing part 14 is completely closed by the fluid seal 52 and the screw head 46. The fluid seal 52 is designed as a flat seal in the present case.

[0032] In the present case, the screw connection receptacle 50 is represented by a concave recess in the upper housing part 14. The screw connection receptacle 50 serves to accommodate the screw head 46, in particular without the screw head protruding from the outer contour of the upper housing part 14 or projecting upwards. The screw connection receptacle 50 can also serve to retain fluid leaks. This makes it particularly easy to determine the tightness of the traction battery 10 during initial commissioning or in the operating environment, for example by means of a visual inspection, by examining whether fluid has collected in the screw connection receptacle 50. The screw connection receptacle 50 can in particular be designed as a recess produced by deep drawing.

[0033] At least the shaft 44 of the screw element 30 can be covered with electrical insulation, in particular with plastic. The electrical insulation of the shaft 44 can be part of the shaft or provided by a component separate from the shaft 44, in particular an insulating sleeve. If the shaft 44 of the screw element 30 is electrically insulated, electrical contact between the screw element 30 and the cell contact system 26 can be particularly well avoided in the event of a crash. The screw element 30 can be made, at least in some regions, from an electrically non-conductive material. The screw element 30 can be made, for example, from steel or a carbon fiber reinforced plastic. The screw receptacle 34 is made, in the present case, from a solid material. In particular, the screw receptacle 34 is made from steel and / or aluminum and / or a fiber reinforced plastic.The screw receptacle 34 can have an internal thread and / or an external thread. The screw receptacle 34 can have a latch or pawl or a clamp fit for receiving the screw element 30. Furthermore, the screw receptacle 34 can have a contact surface that is designed to connect to the housing base 12. In the present case, the contact surface is provided by the plate element 37. The screw receptacle 34 is designed in particular to be welded to the housing base 12 via the contact surface, in particular by spot welding. Alternatively or additionally, the screw receptacle 34 can have a second latch or pawl or a second clamp fit, via which the screw receptacle 34 can be connected to the housing base 12.In this case, the screw receptacle 34 has the deformation region 40 in the form of a crumple zone, which is designed to absorb deformations between the housing lower part 12 and the cell carrier 18, for example, in the event of a vertical crash. Furthermore, the screw receptacle 34 has a further circumferential contact surface, which is designed to bear against the wall of the cell carrier 18 delimiting the opening 32, whereby the cell carrier 18 can be centered relative to the screw receptacle 34 by placing the second contact surface against the cell carrier 18. This second contact surface can be provided, in particular, by the radially projecting collar 42.

[0034] In the present case, the screw receptacle 34 is formed from a sheet metal turned part which has an upper tube segment with an internal thread in relation to the axial direction A, which forms the screw-in sleeve 38, a lower tube segment with a corrugated wall geometry in the manner of a crumple tube, which adjoins the upper tube segment downwards in the axial direction A and which forms the deformation region 40 in the present case, and a lower circular contact plate, which is the plate element 37.

[0035] The traction battery 10 thus comprises at least one direct screw connection 28 between the upper housing part 14 and the lower housing part 12 in the region of the cell carrier 18. The traction battery 10 comprises a direct feedthrough in the form of the opening 32 of the cell carrier 18, through which the screw element 30 is guided, in particular with a clearance fit to the cell carrier 18. This creates a vertical tension in the traction battery 10, which is mechanically effective in the region of the cell carrier 18 or the battery cells 22, without lateral tension occurring between the screw element 30 and the cell carrier 18 during assembly or operation, or without tight tolerances having to be maintained.When using triangular vertical webs in the cell carrier 18, which are arranged in a cell space between three battery cells 22, as the position for the screw connections 28, a screw connection can be implemented while maintaining minimal cell spacing, so that the energy density of the traction battery 10 is not reduced by the provision of the screw connections 28, in particular in comparison to a glued traction battery 10.

[0036] The feedthrough for the screw connection 28 can further comprise a hole in the cell contact system 26, through which the screw element 30 is guided, in particular by means of a clearance fit to avoid electrical contact. This allows existing, but unused or surplus openings in a standard cell contact system segment to be used for caulking with the cell carrier 18, wherein these openings are systematically located in the axial direction A exactly above the, in particular, triangular vertical webs in the region of the cell carrier 18 and are thus located in the region of the opening 32.

[0037] In particular, it is provided that the screw element 30 and / or the screw receptacle 34 are thermally resistant, for example, by means of a material such as steel or aluminum, or by means of a sheath. As a result, the screw connection 28 remains mechanically intact even in the event of a cell failure, for example, in the event of hot gas escaping during a thermal runaway, which is accompanied by increased housing stress due to internal overpressure.

[0038] It can be provided that the cell carrier 18 is positioned or centered laterally relative to the housing base 12 during assembly by means of two screw receptacles 34, in particular via the circumferential centering surface of the screw receptacle 34. This enables simplified, positionally accurate assembly of the cell carrier 18 relative to the housing base 12, whereby lateral position tolerances for positioning the cell contact system and other electrical connections, in particular sheet metal webs, over electrical pole surfaces of the battery cells 22 for welding them can be maintained.

[0039] It is possible for the cell carrier 18 to be constructed from two or more flat, vertically and thus superimposed partial cell carriers in the axial direction A. A screw receptacle, such as a threaded rod, can be permanently incorporated into the cell carrier 18. Thus, the lower housing part 12 or the upper housing part 14 can be directly and firmly clamped to the cell carrier 18 by means of a screw connection, for example by placing respective nuts on opposite ends of the threaded rod, which are each arranged on the outside of the lower housing part 12 or the upper housing part 14. This makes it possible to adapt to an assembly sequence. At least one further component, in particular a respective fluid guide 24, can be arranged between the cell carrier 18 and the upper housing part 14 or the lower housing part 12.This respective fluid guide 24 can, in particular, be a flow grid for fluid guidance in the immersion-temperature-controlled traction battery 10. Alternatively or additionally, the further component can be a support structure for forming a gas discharge path in the event of a fault in a gassing battery cell 22 during a so-called thermal runaway or a structure for forming an area for absorbing deformations, in particular vertical deformations in the event of a vertical crash.

[0040] In addition to the battery cells 22, the traction battery 10 can comprise further components that are to be mechanically arranged or held and / or thermally conditioned. These further components can be electronic components such as circuit boards or circuits, in particular CSCs, R-Boxes, or DC / DC converters. Alternatively or additionally, the components can be plate or tube coolers through which, for example, water / glycol coolant or air can flow. Further alternatively or additionally, the components can be evaporators or condensers through which, for example, R1234yf, R744, R290, or water can flow as a coolant.Furthermore, alternatively or additionally, the components may be valves, such as rotary gates, slide valves, flaps or cones, through which an immersion fluid or another cooling or refrigerant flows at least temporarily.

[0041] Overall, the invention shows how a high-voltage storage device, in this case the traction battery 10, can be implemented with a screwed housing. List of reference symbols 10 Traction battery 12 Housing base 14 Upper housing part 16 Recording room 18 cell carriers 20 rounds 22 battery cells 24 Fluid guide 26 Cell contact system 28 screw connection 30 screw element 32 Opening 34 screw holder 36 push-through opening 37 Plate element 38 screw-in sleeve 40 deformation range 42 collar 44 shaft 46 screw head 48 threaded sleeve 50 screw connection holder 52 Fluid seal A axial direction QUOTES CONTAINED IN THE DESCRIPTION

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

[0000] DE 10 2021 128 304 A1

[0002]

Claims

[1] Traction battery (10) for a motor vehicle, with a housing comprising an upper housing part (14) and a lower housing part (12), which housing delimits a receiving space (16) in which at least one battery module is received, wherein the battery module comprises a cell carrier (18) by means of which a plurality of battery cells (22) of the traction battery (10) are held, wherein the cell carrier (18) is held both on the upper housing part (14) and on the lower housing part (12) via at least one screw connection (28). [2] Traction battery (10) according to claim 1, characterized by that the housing upper part (14) is screwed to the housing lower part (12) by means of the at least one screw connection (28), whereby the cell carrier (18) is clamped between the housing upper part (14) and the housing lower part (12), wherein a screw element (30) of the screw connection (28) extends through the cell carrier (18). [3] Traction battery (10) according to claim 1, characterized by that the cell carrier (18) is screwed to the housing upper part (14) via at least one first screw connection and is screwed to the housing lower part (12) via at least one second screw connection. [4] Traction battery (10) according to claim 2 or 3, characterized by that a screw receptacle (34) with a first thread is provided on the upper housing part (14) or on the lower housing part (12), which screw receptacle can be brought into engagement with a second thread of the screw element (30) to form the screw connection (28), wherein the screw receptacle (34) is at least partially inserted into an opening (32) of the cell carrier (18). [5] Traction battery (10) according to claim 4, characterized by that the screw receptacle (34) for centering the cell carrier (18) in the housing rests at least partially without play on a wall of the cell carrier (18) delimiting the opening (32). [6] Traction battery (10) according to claim 5, characterized by that the screw receptacle (34) has a radially projecting collar (42) which rests around its entire outer circumference without play on the wall of the cell carrier (18) delimiting the opening (32). [7] Traction battery (10) according to one of claims 4 to 6, characterized byin that the screw receptacle (34) is sleeve-shaped and has a deformation region (40) which is formed by a longitudinal section of the screw receptacle (34) running in the axial direction (A), in which section the screw receptacle (34) has a wave-shaped wall, whereby the screw receptacle (34) is deformed in the deformation region (40) along the axial direction (A) before a further region of the screw receptacle (34) is deformed in this axial direction (A), wherein the axial direction (A) runs parallel to a screwing-in direction in which the threads of the screw receptacle (34) and of the screw element (30) are inserted into one another. [8] Traction battery (10) according to one of claims 4 to 7, characterized by that the screw receptacle (34) is glued to the lower housing part (12) or to the upper housing part (14). [9] Method for producing a traction battery (10) for a motor vehicle, in which at least one battery module is received in a receiving space (16) which is delimited by a housing comprising an upper housing part (14) and a lower housing part (12), wherein the battery module comprises a cell carrier (18) by means of which a plurality of battery cells (22) of the traction battery (10) are held, and in which the cell carrier (18) is fastened to both the upper housing part (14) and the lower housing part (12) via at least one screw connection (28). [10] Motor vehicle with a traction battery (10) according to one of claims 1 to 8.

Images