Housing Unit

Abstract

The present invention relates to a housing unit for an electrical storage means, comprising a bottom tray (3) with a bottom (7) and an annular closed tray frame (6) integrally manufactured by deformation processing from a metal material, and a structural frame (4) having a number of frame members (8, 9, 10, 11) and a number of reinforcing members (12), each of which is manufactured from a steel material and is connected to one another to form a structural frame, the structural frame (4) being inserted into and connected to the bottom tray (3), a yield strength of the steel material of the structural frame (4) being at least 10% greater than a yield strength of the metal material of the tray frame (6), the housing unit further comprising a lid (5) removably connectable to the tray frame (6), the tray frame (6) and the lid (5) enclosing an accommodating space for the electrical storage means.

Description

[Technical field]

[0001] The invention relates to a housing unit for accommodating electrical storage means, in particular for motor vehicles which can be driven by an electric motor.

[0002] An electric vehicle has, among other things, an electric machine as a drive source electrically connected to an electric storage means. In a drive mode, the electric machine converts electrical energy into mechanical energy for driving the vehicle. The electric storage means, also called a battery or storage battery, is usually accommodated in a battery box that is mounted on the underside of the vehicle, including the body.

[0003] The battery housing known from JP 2021-64448 A, which forms a generic concept, has a frame with an opening and a tray inserted into the frame. The frame is closed from above by an upper cover and from below by a lower cover. The frame is assembled as a skeleton from a number of extruded profiles made of an aluminum alloy or a magnesium alloy. Alternatively, the frame can be manufactured from high-tensile steel. The tray consists of an aluminum alloy or a magnesium alloy.

[0004] From DE 10 2016 121 247 A1 a battery support is known which comprises a tray for receiving the battery and a cover for closing the tray. The tray is a thin-walled sheet metal component produced in one piece by forming, which is made from an aluminum alloy having an elastic limit Rp0.2 > 250 MPa. Reinforcement struts are arranged on the outside of the tray, as well as an annular frame made of a profiled material.

[0005] A battery housing with a tray is known from DE 10 2019203400 A1. Along the annular tray wall, a reinforcement in the form of a profile made of hardened steel material is arranged.

[0006] A housing unit with a frame, a bottom and a lid, known from WO 2021 / 009256, forms a receiving space for an electrical storage means. The frame has a number of frame parts made of a metal material with a variable sheet metal thickness over its length. The bottom is connected to the frame, thereby forming a closed tray. The bottom can have an integrated cooling structure, through which a cooling medium can flow.

[0007] From DE 10 2018 106 399 A1 a housing unit is known which comprises a tray unit and a lid unit, the tray unit having a first molded part and a second molded part which are produced from a flexible rolled metal material and are connected to one another so as to have a variable sheet metal thickness in the longitudinal direction of the respective molded part.

[0008] From DE 10 2016 120 826 A1 a battery housing for a vehicle driven by an electric motor is known, which has a tray part with a bottom and a side wall integrally formed on the bottom, and a frame structure which surrounds the tray part on the outside and forms a cavity.

[0009] The problem underlying the invention is to propose a housing unit for accommodating electrical storage means, which has good sealing properties, high corrosion resistance and low weight.

[0010] According to the invention, a housing unit for accommodating an electrical storage means for an electric drive of an electrically drivable motor vehicle is proposed, which comprises a bottom tray with a bottom and an annular closed tray frame manufactured by deforming from a metal material, a structural frame having a number of frame members connected to each other to form an annular frame and a number of reinforcing members extending between two oppositely located frame members, the frame members and the reinforcing members each being manufactured from a steel material and connected to each other to form a structural frame, the structural frame being inserted into the bottom tray and connected to said bottom tray, the yield strength of the steel material of the structural frame being at least 10% greater than the yield strength of the metal material of the tray frame, the housing unit further comprising a lid removably connectable to the tray frame, the tray frame and the lid enclosing an accommodating space for the electrical storage means.

[0011] One advantage is that the individual components of the housing unit can be well adapted to the various technical requirements in terms of their configuration. For example, the tray frame, due to being manufactured in a deformable material in a deformable manner, has particularly good sealing and corrosion protection functions, since the tray frame forms the outer area of ​​the housing unit, so that no further welded seams are required here for the attachment of other components. All other components located inside the tray frame, in particular the structural frame, are thus best protected against corrosion. The average sheet metal thickness of the tray frame can be reduced to the minimum required for this technical requirement. In general, an average sheet metal thickness of the tray frame is possible, in particular between 1.0 mm and 3.0 mm, in which case the reduced sheet metal thickness can be, for example, less than 1.4 mm or even less than 1.2 mm. The tray frame is functionally separated from the structural frame and thus does not have to assume any structural-mechanical role. This allows the material quality, sheet metal thickness and, if applicable, the coating of the bottom tray to be optimized for sealing and corrosion protection functions. In this way, good functional fulfilment and low weight of this large and therefore particularly weight-related component can be achieved.

[0012] In contrast, the structural frame or at least its individual components can be optimized with regard to their structural mechanical role or strength and / or stiffness without having to make compromises on the basis of corrosion protection. The dimensioning of the individual frame components and / or reinforcement components can be carried out individually depending on the expected loads. By appropriately reducing the thickness of the frame parts and / or reinforcement components in low load areas, material can be saved, so that the housing unit ultimately has a low weight without losses in terms of mechanical properties and can therefore be manufactured cheaply. By appropriately increasing the thickness of the frame parts and / or reinforcement components in areas subject to higher loads, in particular in areas relevant for crashes, a higher strength can be achieved, so that the housing unit can absorb high loads without being destroyed.

[0013] In the context of this disclosure, the "average thickness" of a part having a variable thickness may be, for example, the average thickness accumulated over the length of each part, or the average thickness between the maximum and minimum absolute thicknesses of the part. For parts having a constant thickness over their length, the average thickness is equal to the nominal thickness.

[0014] The sheet metal material of the tray frame may preferably have a breaking elongation of at least 15%. This value may relate to the raw material, i.e. before the sheet metal material is transformed into the tray frame, or to the tray frame transformed as a finished product. In the context of the present disclosure, the breaking elongation A represents the length change remaining after the break of the sample relative to the initial measured length L0 (Lu-L0), i.e. A=(Lu-L0) / L0*100%. The breaking elongation A of the material of the tray frame is preferably greater than the breaking elongation of the material of the structural frame. Means for determining the breaking elongation and carrying out the test are described, for example, in DIN EN ISO 6892-1 or ASTM E8 / E8M. In particular, tensile samples with rectangular cross section or for flat products may be used. The initial measuring length L0 of the sample, to which at least the specified breaking elongation A of 15% applies, may be, for example, 50 mm, in which case other sample lengths according to DIN EN ISO 6892-1 or ASTM E8 / E8M are likewise possible.

[0015] The tray frame can be produced as a one-piece formed part, for example from a readily deformable steel material or from a light metal, such as aluminum or an aluminum alloy. In this case, the materials used in particular have a tensile strength and / or yield strength (Rp0.2) of less than 450 MPa. The tray frame is preferably produced from a one-piece sheet metal blank, which is processed by a forming operation, in particular a deep drawing operation, and optionally a cutting operation, to form the tray frame. In the case of particularly large tray frames, a number of individual sheet metal parts can optionally first be produced separately and connected to one another in a material-bonding manner, for example by welding, after which this material composite is then formed into the tray frame as one part. Within the scope of the forming process, the tray frame is produced with a beveled wall area forming a drawing slope.

[0016] In a first embodiment, the tray frame can be manufactured in one piece with an integrated bottom. In this case, the tray frame and the bottom form a correspondingly gas-tight and liquid-tight one-piece bottom tray. The bottom tray can optionally have a cooling structure. The bottom tray with integrated cooling structure can be manufactured, for example, by roll-bonding two aluminum strips, which are then singulated to form a composite material, which is then deformed into the tray shape, in particular by deep drawing, and the hollow space is expanded. In this configuration, the tray frame and the bottom form a one-piece bottom tray of the same material.

[0017] In one variant, the tray frame and the bottom can first be manufactured separately and then sealingly joined to one another. In this case, the bottom has an integrated cooling structure through which a cooling medium can flow. The tray frame and the cooling bottom can, for example, be joined to one another in a liquid-tight and gas-tight manner, which can be done, for example, using a hybrid joining technique consisting of friction welding or gluing with riveting. In this embodiment, the tray frame and the cooling bottom can be manufactured from different materials, for example, the tray frame can be manufactured from cold-formable steel and the cooling bottom can be manufactured from aluminum or an aluminum alloy.

[0018] The cooling bottom or the cooling structure may be produced from a number of aluminum strips bonded together by roll-bonding. The aluminum strips are bonded together and shortened to individual blanks by heating and rolling in the bonding area. The hollow area is then produced by applying pressure to the area lying outside the bonding area, which deforms this area to form a hollow space. The hollow area of ​​the cooling bottom is preferably formed only in one of the two overlapping aluminum sheets, i.e. one sheet metal part is flat, while the other sheet metal part is deformed. In this case, the flat sheet metal part and the deformed sheet metal part bonded to the flat sheet metal part may have the same or different sheet metal thicknesses, which may be, for example, between 0.8 mm and 2.0 mm. The cooling bottom may be produced from a single roll-bonded part or from a number of roll-bonded parts bonded together.

[0019] The tray frame may have a Z-shaped cross-sectional shape with a lower flange area that merges into or is connected to the bottom, an annular wall area that extends away from the bottom, and an upper flange area that is connected to the wall area and is used for attaching the lid, the extension of the wall area towards the upper flange area being used as a drawing ramp for the forming tool.

[0020] The upper flange area forms a flat sealing surface which in particular sealingly connects to a corresponding surface of a lid, which can be connected, in particular removably, to the tray frame, and the lower flange area merges integrally with the base in a one-piece configuration or forms a flat sealing surface which sealingly connects to a corresponding surface of the cooling base in a two-part configuration.

[0021] The structural frame comprises a number of frame members assembled into an annular frame and a number of reinforcing members extending between or supporting the two lateral frame members. The frame members and / or the reinforcing members may be adapted to the respective technical requirements in terms of their strength and rigidity. For example, at least some of the frame members and / or at least some of the reinforcing members may have a variable sheet metal thickness over the length of the respective member.

[0022] Depending on the special technical requirements, the frame elements can be formed in the form of a two-part hollow profile with a C-shaped outer profile connected to it and a C-shaped inner profile or in the form of a one-piece profile. By using two-part or hollow profiles, particularly high bending resistance moments can be achieved, which can be, for example, more than 6500 mm3 depending on the material and sheet metal thickness.

[0023] The frame elements and the reinforcing elements may be made of the same or different steel materials. For example, at least some or all of the frame elements of the structural frame may be made of martensitically hardenable steel, in particular manganese-boron alloy heat-treated steel, such as 17MnB3, 22MnB5, 26MnB5 or 34MnB5, in which case steels of other natures are possible as well. At least some, preferably all of the frame elements of the structural frame may be provided with a corrosion protection layer, in particular consisting of an aluminum alloy. The corrosion protection layer provides a good protection against corrosion. The final shape of the parts made of martensitically hardenable steel materials is preferably produced in the course of hot deformation, which may also be called press hardening. For this, a pre-coated starting element, which may have a tensile strength of at least 500 MPa, is first heated to the austenitizing temperature and then inserted in the hot state into a hot forming die, deformed therein and rapidly cooled, which produces a martensitic structure. The finished, ie deformed and hardened, part may have an ultimate tensile strength of at least 900 MPa, preferably at least 1300 MPa.

[0024] The reinforcing element may be made, in particular, from cold-rolled steel, for example microalloyed steel such as HC420, dual-phase steel such as DP800 or DP1000, or multi-phase steel. These steels are transformed from blanks into finished components in the course of cold deformation. As cold-formed steels can be easily deformed, more complex geometries of the reinforcing element can also be produced. The reinforcing element may furthermore be provided with a corrosion protection layer, in particular made of a zinc alloy. However, it is also possible to use hot-formed steel, as explained in connection with the frame element. In this case, preferably an aluminum alloy is used as the corrosion protection layer.

[0025] The reinforcing members may include lateral and / or longitudinal supports arranged between the frame members and rigidly connected to the frame members, for example by welding. The frame members connected to the reinforcing members are supported to each other via the reinforcing members. Overall, a sturdy structural frame is thus formed which can be inserted into and connected to the bottom tray as a prefabricated construction unit.

[0026] In one possible embodiment, at least some of the reinforcing members may have machined threads, which may be produced in particular by a drilling, deep drawing, embossing and / or cutting process, which may be used for or may be formed for the attachment of a battery module that can be inserted between the lid parts and / or the reinforcing members.

[0027] For mounting the housing unit to the vehicle body, a plurality of through-thread units may be provided, each of which may have a sealed support sleeve that passes through the reinforcement member. The number of through-threads of the housing unit may be, for example, 2-5 per reinforcement member.

[0028] Depending on the technical requirements, at least some of the reinforcing elements may have a variable sheet metal thickness over their maximum length, in which case the sheet metal thickness may be increased in particular in the region of the machined thread and / or in the region of the through-thread and / or in the region of the end-side mounting part connected to the frame.

[0029] The lid may be formed in one piece or from several parts, each optionally with a variable or uniform material thickness.

[0030] When the lid is joined to the tray frame-bottom unit, a closed housing unit is formed and the housing unit is sealed, effectively preventing battery acid from escaping from the housing unit or dirt from entering the housing unit.

[0031] Preferred embodiments will now be described with reference to the drawings. [Brief description of the drawings]

[0032] [Figure 1A] 1 shows a perspective exploded view of a first embodiment of a housing unit for accommodating electrical storage means according to the invention; FIG. [Figure 1B] FIG. 1B is a cross-sectional view showing details of the housing unit shown in FIG. 1A. [Figure 2A] FIG. 2 is a perspective view showing the reinforcing member for a housing unit according to the present invention alone; [Figure 2B] 2B is a cross-sectional view showing the reinforcing member shown in FIG. 2A. [Figure 3A] FIG. 1B is a plan view of the housing unit shown in FIG. 1A. [Figure 3B] FIG. 3B is an enlarged view showing a detail of the housing unit shown in FIG. 3A. [Figure 3C] 3C shows a cross-section of the housing unit taken along section line 3C-3C shown in FIG. 3B. [Figure 4A] FIG. 2 is a perspective exploded view showing another embodiment of a housing unit according to the present invention. [Figure 4B] FIG. 4B is a cross-sectional view showing a detail of the housing unit shown in FIG. 4A. [Diagram 5] FIG. 2 is a perspective exploded view of one alternative embodiment of a housing unit for accommodating electrical storage means according to the invention; [Figure 6] 1 is a perspective exploded view of one alternative embodiment of a bottom tray and structural frame for a housing unit according to the present invention; FIG. [Figure 7A] FIG. 2 is a perspective exploded view showing another embodiment of a housing unit according to the present invention. [Figure 7B] FIG. 7B is an isolated perspective view of the bottom tray shown in FIG. 7A as seen from below.

[0033] 1A and 1B, also collectively designated as Fig. 1, show a first embodiment of a housing unit 2 according to the invention in which an electrical storage means (not shown) can be accommodated. Such a housing unit 2 can be coupled to the body of a motor vehicle. The electrical storage means is used to store electrical energy capable of supplying current to an electric motor of an electrically drivable motor vehicle, sometimes called a battery module.

[0034] The housing unit 2 comprises a bottom tray 3, a structural frame 4 and a lid 5. In this embodiment, the bottom tray 3 is made in two parts and includes a one-piece tray frame 6 manufactured by deformation and a bottom 7 sealingly connected to the tray frame 6. The connection may be made, for example, by welding and / or gluing. In the joined state, the bottom 7 and the tray frame 6 together form the bottom tray 3, which houses the structural frame 4 and the storage means. The structural frame 4 comprises a number of frame members 8, 9, 10, 11 connected to each other to form an annular frame and a number of reinforcing members 12 extending between the two opposite frame members 8, 9. The frame members 8, 9, 10, 11 and the reinforcing members 12 are manufactured from a steel material and connected to each other to form the structural frame 4. The connection may be made, for example, by welding and / or screwing. The structural frame 4 is inserted into the bottom tray 3 and connected to the bottom tray 3. The lid 5 can be removably connected to the tray frame 6, for example by screw fastening (not shown). Overall, a housing is achieved with an inner structural frame 4, which is protected from environmental influences by the outer bottom tray 3 or the lid 5.

[0035] In the following the component group consisting of the bottom tray 3, the structural frame 4 and the lid 5 will be explained in more detail.

[0036] The tray frame 6 is produced in one piece by forming a sheet metal blank, for example by deep drawing and then cutting. In this case, the wall area 13 of the tray frame 6 is produced in particular with a drawing bevel for the forming tool. The tray frame can be produced, for example, from a well-deformable steel material or from a light metal, such as aluminum or an aluminum alloy, where the metal material used preferably has an elongation at break (A50) of at least 15%. The tensile strength and / or yield strength (Rp0.2) is preferably less than 450 MPa. The average sheet metal thickness d6 of the tray frame 6 is preferably less than 1.4 mm, in particular less than 1.2 mm. The average thickness can, for example, relate to the average thickness accumulated over the entire extension length of the tray frame or to the average thickness between the maximum and minimum absolute thicknesses of the tray parts.

[0037] As can be seen in particular in Fig. 1B, the tray frame 6 has a Z- or S-shaped cross section in cross section, in which a lower flange area 14 and an upper flange area 15 are folded in opposite directions from the wall area 13. In this case, the lower flange area 14 is folded inwards and has, in particular, a flat sealing surface which sealingly connects to the bottom 7. The upper flange area 15 is folded outwards and has, in particular, a flat sealing surface which sealingly connects to a corresponding surface of the lid 5, which can be releasably connected to the tray frame 6 via a number of screw fastenings distributed over the entire periphery.

[0038] The bottom 7 has an integrated cooling structure and is sometimes referred to as a cooling bottom in this respect. In the joined state, the bottom 7 and the tray frame 6 together form the liquid-tight and gas-tight bottom tray 3. The cooling bottom is manufactured from a number of sheet metal parts 16, 17, in particular made of aluminum or an aluminum alloy, which are joined to one another by roll bonding. In roll bonding, a release agent is applied to one of the two superimposed metal strips, which are then joined to one another in a joining region 18 by heating and rolling. The release agent, which can be applied by a screen printing method, represents the geometry of the subsequent hollow space. In the regions where the release agent is not applied, the two sheet metal layers are joined to one another in a material-bonding manner. The regions that are not joined to one another are pressurized, so that they are deformed to form a hollow region 19. In this case, the hollow region 19 is formed only in the lower one of the superimposed sheet metal parts. The upper sheet metal element 16 remains flat, thus forming a correspondingly flat contact surface for the battery module. The sheet metal element 16, 17 may have a sheet metal thickness of, for example, 0.8 to 2.0 mm. For a high cooling power, the sheet metal elements 16, 17 may have a high thermal conductivity, in particular above 100 W / mK.

[0039] As can be seen in particular from FIG. 1A, the bottom part 7 has a number of cooling areas 22, which in the assembled state are spatially separated from one another by the reinforcing elements 12. The number of cooling areas 22 can be adapted to the number of storage elements. The reinforcing elements 12 are each connected to the bottom part 7 at a connection area 23 between two adjacent cooling areas 22. Furthermore, connections 24, 25 for circulating the cooling medium through the hollow area 19 are recognizable. In this configuration, the bottom part 7 consists of two roll-bonded bottom parts 20, 20' connected to one another and accordingly has two cooling structures. However, a configuration consisting of a single roll-bonded bottom part with one cooling structure is also possible.

[0040] The reinforcing elements 12 form a connecting web between the two opposite frame elements 8,9, which together with the end frame elements 10,11 extending transversely to the frame elements 8,9 form a closed frame. The number of reinforcing elements 12 can be adapted to the number of reserve elements. In this case, the reinforcing elements 12 extend transversely to the longest length of the housing and are therefore sometimes called transverse supports or transverse struts. Configurations with longitudinal supports are also possible.

[0041] As can be seen particularly in Fig. 1B, the frame members 8, 9, 10, 11 or at least some of them have a C-shaped cross section in this embodiment, with both the upper flange portion 26 and the lower flange portion 27 folded inwardly from the wall portion 28 in the same direction. The reinforcing member 12 may have a U-shaped cross section in cross section, with a bottom flange that attaches to the bottom tray 3 and end flanges that join the lateral frame members 8, 9. The reinforcing member 12 is attached, e.g. welded, with its ends to the frame members 8, 9, engaging in the inwardly opening hollow space formed by the C-shaped cross section of the frame members 8, 9.

[0042] The frame elements 8, 9, 10, 11 or at least parts of them are preferably manufactured from a hot-formable steel, in particular from a martensitically hardenable heat-treatable steel such as 17MnB3, 22MnB5, 26MnB5 or 34MnB5, in which case a particularly high strength of the elements is achieved by being deformed and hardened during hot forming of the blank into the finished component.

[0043] The reinforcing members 12, or at least parts of them, are preferably made of a cold-formable steel, in particular a cold-rolled micro-alloyed steel such as HC420, a dual-phase steel such as DP800 or DP1000, or a multi-phase steel, which is transformed from a blank into a finished part during cold deformation. Alternatively, the reinforcing members 12 may be made of a hot-formable steel as described above.

[0044] For particularly good corrosion resistance, the frame elements 8, 9, 10, 11 and / or the reinforcing elements 12 of the structural frame 4 can have a corrosion protection layer, in particular made of a zinc-based alloy in the case of cold-formed steel or an aluminum-based alloy in the case of hot-formed steel, which is preferably applied to the steel strip before the deformation process.

[0045] The frame elements 8, 9, 10, 11 and the reinforcing element 12 can be manufactured separately and then connected to one another, for example by welding. Together the frame elements 8, 9, 10, 11 and the reinforcing element 12 form a structural frame 4, which in this case has a ladder-like structure, but not exclusively. Depending on the technical requirements, at least some of the reinforcing elements 12 and / or at least some of the frame elements 8, 9, 10, 11 can have different sheet metal thicknesses over their respective lengths. The structural frame 4 can be inserted in the bottom tray 3, in particular as a pre-manufactured or self-supporting construction unit, and connected to the bottom tray 3, for example by welding or screw fastening.

[0046] 2A and 2B show one possible embodiment of the reinforcing element 12. As can be seen especially in FIG. 2B, the reinforcing element 12 has a U-shaped cross section with two laterally overhanging flange portions 29, 29' for attachment to the bottom tray 3. At the opposite ends, the reinforcing element has end flanges 30, 30' bent laterally for attachment to the longitudinally extending frame elements 8, 9. Optionally, the reinforcing element 12 may have a number of threads 33 formed in the bottom portion 32, which may be produced by a drilling, deep drawing, embossing and / or cutting process. The threads 33 serve for attachment of the lid 5 and / or the battery module. The sheet metal thickness of the lateral support is preferably increased, especially in the region of the formed threads and / or end flanges 30, 30'. Additionally, the reinforcing member 12 may optionally have a number of through openings 34 in the bottom portion 32 through which screws can be passed from the lid to the bottom, as will be described in more detail below with reference to FIG. 3.

[0047] 3A, 3B and 3C, also collectively referred to as Fig. 3, show one possible, non-limiting embodiment for mounting the housing unit 2 according to the invention to the vehicle body, in which a number of through-screw units 35 may be provided, via which one screw each can be guided through the housing unit 2 from the bottom towards the lid, so that the housing unit 2 can be mounted to the vehicle body.

[0048] Each of the through-screw units 35 has an inner sleeve 36, which is inserted into the through-opening 34 of the reinforcing element 12 and is arranged between the two legs 31, 31'. The inner sleeve 36 is supported downwards on the bottom 7 and is attached to the bottom 7 via a lower mounting sleeve 37. In the region of the mounting sleeve 37, the reinforcing element 12 may have a number of openings with inwardly recessed support flanges 21. At the upper end, the inner sleeve 36 is screwed to the lid 5 via a corresponding mounting sleeve 38. The connection between the inner sleeve 36 and the bottom 7 and between the inner sleeve 36 and the lid 5 is sealed, so that no moisture or dirt can penetrate into the housing interior space 39. The number of through-screw units 35 per transverse support is, for example, a maximum of five.

[0049] Figures 4A and 4B, also collectively referred to as Figure 4, show a variant embodiment of a housing unit 2 according to the invention. This variant embodiment corresponds generally to the embodiment shown in Figures 1 to 3, so that reference is made to the above description for the commonalities. In this case, identical or corresponding parts are provided with the same reference numerals as in the above-mentioned Figures 1 to 3.

[0050] The only difference in this embodiment shown in Fig. 4 is the construction of the frame members 8, 9, which are formed in the form of a two-part hollow profile with a C-shaped outer profile 40 and a C-shaped inner profile 41 connected to the outer profile 40. The outer profile 40 and the inner profile 41 are oriented with their upper flange parts 26, 42 and lower flange parts 27, 43 overlapping each other, so that a hollow space is created in cross section. The inner profile 41 may have a number of weight-saving openings 44 over its length. Overall, the frame members 8, 9 have a higher strength, stiffness or a particularly high bending moment resistance in the two profiles.

[0051] In Figure 5, one further embodiment of a housing unit 2 according to the invention is shown. This embodiment corresponds to a large extent to the embodiment shown in Figure 4, so in this respect reference is made to the description of Figure 4 with regard to the commonalities. In this case, identical or corresponding parts are provided with the same reference numerals as in the above-mentioned Figures 1 to 4.

[0052] The particular feature of this embodiment shown in FIG. 5 is that the bottom tray 3 is manufactured in one piece, i.e. the tray frame 6 and the bottom 7 form one part, which is manufactured in the course of a forming process from a blank or a blank composite, in particular by deep drawing. The bottom 7 does not have a cooling structure in this configuration and is formed from a deep-drawn sheet metal. Nevertheless, to provide a cooling function for the battery module, an upper cooling bottom 45 is provided, which rests on the structural frame 4 or is arranged between the structural frame 4 and the lid 5. The bottom tray 3 manufactured in one piece has the advantage that no joints are present. The mounting of the housing unit 2 to the vehicle body can take place in this configuration, for example, via a circumferentially extending flange of the tray frame 6, which can alternatively also be achieved in this case by means of a screw, as shown in FIG. 3.

[0053] Figure 6 shows an embodiment in which the structural frame 4 has been modified. The lid is not shown here for simplicity. This embodiment corresponds to a large extent to the embodiment shown in figure 5, so in this respect reference is made to the description of figure 5 for the commonalities. In this case, identical or corresponding parts are provided with the same reference numerals as in the above-mentioned figures 1 to 5.

[0054] The embodiment shown in Fig. 6 is characterized in that the structural frame 4 has laterally extending reinforcing elements 12 and longitudinally extending reinforcing elements 12' which extend between the frame elements 8, 9, 10, 11, thereby forming a window-like support structure as a whole. The bottom tray 3 is manufactured in one piece, where the tray frame 6 and the bottom 7 form one part which is manufactured from a material or a material composite by deformation, in particular by deep drawing. The bottom 7 does not have a cooling structure in this configuration, but can also be provided with an upper-located cooling bottom, as shown in Fig. 5. However, it is self-evident that the bottom 7 can also have a cooling structure, for example as shown in Fig. 7.

[0055] Figures 7A and 7B, also collectively referred to as Figure 7, show one further embodiment of a housing unit 2 according to the invention. This embodiment corresponds generally to the embodiment shown in Figure 4, so reference is made to the above description for the commonalities. In this case, identical or corresponding parts are provided with the same reference numerals as in Figures 1 to 6 above.

[0056] The particular feature of this embodiment shown in Fig. 7 is that the bottom tray 3 is manufactured in one piece, i.e. the tray frame 6 and the bottom 7 form one part, in particular produced by deep drawing, from a material composite consisting of two roll-bonded bottom parts 20, 20' during a deformation process. The bottom part 7 and the tray frame 6 form a one-piece bottom tray 3, which in this configuration has no joints between them. As can be seen in particular in Fig. 7B, the bottom tray 3 has two roll-bonded bottom parts 20, 20' joined to one another and correspondingly two cooling structures 46, 46' as described above. However, a configuration consisting of a single roll-bonded material composite with one cooling structure is also possible.

[0057] Overall, the above-described housing unit 2 with the formed tray frame 6 has the advantage of a high sealing performance, since weld seams are avoided in the wetted areas, thus increasing safety. A functional separation can be made between the pure sealing and corrosion protection functions and the pure structural and mechanical functions. In this case, the sealing and corrosion protection functions are taken up by the bottom tray 3, which allows the sheet metal thickness and weight to be reduced to a minimum. The structural and mechanical functions are taken up by the structural frame 4, which is sealed and enclosed by the bottom tray 3 and the lid 5, and which may possibly be load-optimized and formed with a variable sheet metal thickness, e.g. made of a tailor-rolled blank. [Explanation of symbols]

[0058] 2 Housing Unit 3 Bottom Tray 4 Structural Frame 5 Lid 6 Tray Frame 7 Bottom 8 Frame members 9 Frame members 10 Frame members 11 Frame members 12 Reinforcement members 13 Wall area 14 Flange Area 15 Flange area 16 Thin metal plate components 17 Thin metal plate components 18 Combined area 19 Hollow area 20,20' Bottom member 21 Support flange 22 Cooling area 23 Combined area 24 Connection 25 Connection 26 Flange part 27 Flange part 28 Wall section 29,29' flange part 30,30' End flange 31,31' legs 32 Bottom part 33 Threads 34 Through hole 35 Through-hole screw unit 36 Inner Sleeve 37 Mounting sleeve 38 Mounting sleeve 39 Housing internal space 40 Outer molding material 41 Inner molding material 42 Flange part 43 Flange part 44 Aperture 45 Cooling bottom 46,46' cooling structure d6 Thickness

Claims

1. 1. A housing unit for accommodating electrical storage means for an electric drive of an electrically drivable motor vehicle, comprising: A bottom tray (3) having a bottom (7) and an annular closed tray frame (6) made by forming from a metal material; a structural frame (4) having a plurality of frame members (8, 9, 10, 11) connected to each other to form a ring-shaped frame and a plurality of reinforcing members (12) extending between two of the frame members (8, 9), the frame members (8, 9, 10, 11) and the reinforcing members (12) being each made of a steel material and connected to each other to form the structural frame (4), the structural frame (4) being connected to the bottom tray (3); the yield strength of the steel material of the frame members (8, 9, 10, 11) and the reinforcing member (12) is at least 10% greater than the yield strength of the metal material of the tray frame (6); The housing unit further comprises a lid (5) removably connectable to the tray frame (6), the tray frame (6) and the lid (5) enclosing a storage space for electrical storage means, A housing unit, characterized in that the structural frame (4) is arranged inside the tray frame (6) in the bottom tray (3).

2. the bottom tray (3) is manufactured in two parts, the tray frame (6) is sealingly joined to the bottom (7), the bottom (7) having an integrated cooling structure through which a cooling medium can flow; the bottom part (7) is manufactured from a number of aluminum sheets (16, 17) bonded to one another by roll bonding, the aluminum sheets (16, 17) being bonded to one another in a bonding region (18) by rolling and spaced apart from one another in a hollow region (19) forming the cooling structure, The housing unit according to claim 1 .

3. The tray frame (6) has a Z-shaped cross section in cross section, the tray frame (6) starting from a lower flange area (14) and extending through a wall area (13) adjacent to the lower flange area (14) towards an upper flange area (15), the upper flange region (15) forms a flat sealing surface that sealingly mates with a corresponding surface of the lid (5); and The lower flange area (14) forms a flat sealing surface that sealingly mates with a corresponding surface of the bottom part (7).

3. A housing unit according to claim 1 or 2.

4. 3. The housing unit according to claim 1 or 2, wherein the tray frame (6) is manufactured from a sheet metal material having a yield strength (Rp0.2) of less than 450 MPa, an elongation at break (A50) of at least 15%, and an average sheet metal thickness of less than 3.0 mm.

5. 3. A housing unit according to claim 1 or 2, characterized in that the bottom tray (3) is produced in one piece from the tray frame (6) and the bottom (7) by forming, in particular by deep drawing.

6. 3. A housing unit according to claim 1 or 2, wherein at least some of the reinforcing members (12) have threads (33) machined for mounting a battery module insertable between the lid (5) and / or the reinforcing members (12), and wherein a plurality of through-thread units (35) are provided for mounting the housing unit (2) to a vehicle body.

7. 3. A housing unit according to claim 1 or 2, wherein at least some of said reinforcing members (12) have a variable sheet metal thickness over the longest length of each reinforcing member.

8. at least some of the frame members (8, 9, 10, 11) of the structural frame (4) are manufactured from a steel that can be hardened in a martensitic state by hot deformation processing, at least some of the frame members (8, 9, 10, 11) of the structural frame (4) are provided with a corrosion protection layer made of an aluminum alloy; 3. A housing unit according to claim 1 or 2.

9. At least some of the frame members (8, 9, 10, 11) of the structural frame (4) have a variable sheet metal thickness over the longest length of each frame member; and / or At least some of the frame members (8, 9, 10, 11) of the structural frame (4) are formed in the form of hollow profiles consisting of a C-shaped outer profile member (40) and a C-shaped inner profile member (41) connected to the outer profile member (40).

3. A housing unit according to claim 1 or 2.

10. at least some of the reinforcing elements (12) of the structural frame (4) are manufactured from cold-rolled steel by cold deformation processing and having a yield strength of up to 550 MPa, At least some of the reinforcing members (12) of the structural frame (4) are provided with a corrosion protection layer made of a zinc alloy.

3. A housing unit according to claim 1 or 2.

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