Battery Housing For A Vehicle Driven By An Electric Motor

Abstract

The invention relates to a battery housing (1) for a vehicle driven by an electric motor, which is to be installed in the floor region of a vehicle, having a frame (2), which encloses at least one battery module, and a floor (3), which is connected to the frame (2), The floor (3) takes the form of a sandwich construction and forms hollow chambers (18, 18′), which can be used as temperature-control channels for guiding through a fluid by virtue of end-side openings in adjacent hollow chambers (18, 18′) being connected to one another at their two ends.

Claims

1. A battery housing for a vehicle driven by an electric motor, to be installed in the floor region of a vehicle, with a frame (2) enclosing at least one battery module and a floor (3) connected to the frame (2), wherein the floor (3) is equipped with collision protection, wherein the floor (3) is designed as a sandwich construction, which comprises a lower sheet (6, 6.1, 6.2), an upper sheet (7, 7.1, 7.2) spaced apart from the lower sheet (6, 6.1, 6.2), and a structural sheet (8, 8.1, 8.2) positioned in between and connected to the lower sheet and to the upper sheet, wherein the structural sheet (8, 8.1, 8.2) is formed, at least in sections in its cross-section, from a repeating sequence (F) comprising a first contact section (9 9′, 9.1, 9.1′, 9.2, 9.2′), a first bridging section (10, 10.1, 10.2), a second contact section (11, 11.1, 11.2), and a second bridging section (12, 12.1, 12.2), wherein the first contact section (9, 9′, 9.1, 9.1′, 9.2, 9.2′) is connected to the lower sheet (6, 6.1, 6.2) and the second contact section (11, 11.1, 11.2) is connected to the upper sheet (7, 7.1, 7.2), and wherein the bridging sections (10, 10.1, 10.2, 12, 12.1, 12.2) each have a contact section (9, 9′; 9.1, 9.1′; 9.2, 9.2′) connected to the lower sheet (6, 6.1, 6.2) with a second contact section (11, 11.1, 11.2) connected to the upper sheet (7, 7.1, 7.2), characterized in that the hollow chambers (18, 18′) formed by the structural sheet (8, 8.1, 8.2) with its bridging sections (10, 10.1, 10.2, 12, 12.1, 12.2) and the second contact sections (11, 11.1, 11.2) connecting them and the upper sheet (7, 7.1, 7.2) connecting the channels formed by these sections can be used as temperature-control channels for conducting a fluid, in that end-side openings of adjacent hollow chambers (18, 18′) are connected to one another at the two ends thereof.

2. The battery housing according to claim 1, characterized in that the upper sheet (7, 7.1, 7.2) is thinner than the lower sheet (6, 6.1, 6.2).

3. The battery housing according to claim 3, characterized in that the hollow chambers each open into a collector at the end-side.

4. The battery housing according to any of claims 1 to 3, characterized in that the contact sections (9, 9′, 9.1, 9.1′, 9.2, 9,2′, 11, 11.1, 11.2) are connected to the respectively adjacent upper or lower sheet (6, 6.1, 6.2, 7, 7.1, 7.2) over their entire width (B1, B1.1, B2, B2.2).

5. The battery housing according to any of claims 1 to 4, characterized in that the first contact sections (9, 9′, 9.1, 9.1′, 9.2, 9.2′) of the structural sheet (8, 8.1, 8.2) are glued to the lower sheet (6, 6.1, 6.2), and the second contact sections (11, 11.1, 11.2) of the structural sheet (8, 8.1, 8.2) are soldered to the upper sheet (7, 7.1, 7.2).

6. The battery housing according to any of claims 1 to 5, characterized in that the first contact sections (9, 9′, 9.1, 9.1′, 9.2, 9.2′) of the structural sheet (8, 8.1, 8.2) have a smaller width than the second contact sections (11, 11.1, 11.2) of the structural sheet (8, 8.1, 8.2).

7. The battery housing according to any of claims 1 to 6, characterized in that the distance (D) between the upper sheet (7, 7.1, 7.2) and the lower sheet (6) is several times smaller than the width (B1, B1.1, B2, B2.2) of the contact sections (9, 9′, 9.1, 9.1′, 9.2, 9.2′, 11, 11.1, 11.2) of the structural sheet (8, 8.1, 8.2).

8. The battery housing according to any of claims 1 to 6, characterized in that the bridging sections (10, 10.1, 10.2, 12, 12.1, 12.2) of the structural sheet (8, 8.1, 8.2) are longer in the cross-section than the critical buckling length of same.

9. The battery housing according to any of claims 1 to 8, characterized in that the bridging sections (10, 10.1, 10.2, 12, 12.1, 12.2) transition into the adjacent contact sections (9, 9′, 9.1, 9.1′, 9.2, 9.2′, 11, 11.1, 11.2) with a radius (14, 14.1, 15, 15.1, 16, 16.1, 17, 17.1).

10. The battery housing according to any of claims 1 to 9, characterized in that the bridging sections (10, 10.1, 10.2, 12, 12.1, 12.2) connect the contact sections (9, 9.1, 9.2, 11, 11.1, 11.2, 9′, 9.1′, 9.2′) to each other in the distance direction between the lower sheet (6, 6.1, 6.2) and the upper sheet (7, 7.1, 7.2).

11. The battery housing according to any of claims 1 to 10, characterized in that the first and second bridging sections (10, 12) extend over the entire longitudinal or transverse extension of the structural sheet (8).

12. The battery housing according to claim 11, characterized in that the end-side openings of adjacent hollow chambers (18, 18′) are connected to one another at the ends thereof offset in relation to one another.

13. The battery housing according to any of claims 1 to 12, characterized in that the structural sheet (8.1, 8.2), for forming the bridging sections (10.1, 10.2, 12, 12.1, 12.2) and the contact sections (9.1, 9.1′, 9.2, 9.2′, 11.1, 11.2), has support projections (22, 22.1).

14. The battery housing according to claim 13, characterized in that such a support projection (22, 22.1) is knob-shaped with a circular outline.

15. The battery housing according to any of claims 13 to 14, characterized in that the structural sheet (8.1, 8.2) has a plurality of support projections (22, 22.1) which are arranged in the manner of a grid in relation to one another.

Description

[0035] The invention is described on the basis of an exemplary embodiment with reference to the appended figures. The following is shown:

[0036] FIG. 1: a battery housing according to the invention in a perspective view;

[0037] FIG. 2: a cross-section through the battery housing shown in FIG. 1;

[0038] FIG. 3: an enlarged section of FIG. 2;

[0039] FIG. 4: an underside view of the battery housing of FIG. 1, with the lower sheet of the floor not visible;

[0040] FIG. 5: an underside view of another battery housing, with the lower sheet of the floor not visible;

[0041] FIG. 6: an enlarged section of a floor sandwich construction corresponding to that of FIG. 3, but with respect to the battery housing shown in FIG. 5; and

[0042] FIG. 7: a section of the floor sandwich construction of a further battery housing corresponding to FIGS. 3 and 6.

[0043] FIG. 1 shows a battery housing 1. This can be closed by a cover, which is not shown in the figures. The battery housing includes a frame 2 and a floor 3. The frame 2 is formed by a peripheral support structure. The frame 2 is equipped on the inside with reinforcement struts 4, 5, one of the reinforcement struts being a longitudinal strut 4, through which the two narrow sides of the frame 2 are connected to one another. The cross struts 5 connect the longitudinal sides of the frame 2 to one another. For the sake of clarity, only one cross strut 5 is identified by the reference numeral in FIG. 1 as an example. The struts 4, 5 are connected to the sides of the frame 2 facing the inside of the battery volume and also to the floor 3 by means of flanges. The longitudinal strut 4 is designed as a continuous strut in the exemplary embodiment shown. The cross struts 5 extend between the frame 2 and the longitudinal strut 4, two cross struts 5 each being arranged in alignment with one another with respect to the longitudinal axis thereof, separated by the longitudinal strut 4. The struts 4, 5 form a compartment. Battery modules can be inserted into this compartment. Each compartment represents a battery module slot. The battery modules are connected to the frame 2, the cross struts 5, and/or the longitudinal strut 4. A special feature of the battery housing 1 is the floor 3 thereof. This is explained below.

[0044] FIG. 2 shows a cross-section in the transverse direction, parallel to the narrow sides of the battery housing 1 of FIG. 1. The floor 3 is connected to the frame 2, which is provided from profiled pieces of the hollow chamber, and connected to the longitudinal strut 4 and the cross struts 5. The floor 3 is a sandwich construction, which is explained below with reference to FIG. 3.

[0045] FIG. 3 shows an enlarged section of the floor 3 shown in FIG. 2. Since the battery housing 1 is to be installed in the floor region of a motor vehicle, the floor 3 is equipped with collision protection. For this purpose, the floor 3 is designed in a sandwich construction. The sandwich construction comprises a lower sheet 6 and an upper sheet 7 spaced apart from the lower sheet 6 by a distance D. These two sheets 6, 7 are flat sheets. The upper sheet 7 delimits the inside of the battery housing together with the frame 2 and the cover, which is not shown in detail. The lower sheet 6 has a greater material thickness than the upper sheet 7. In the exemplary embodiment shown, the material thickness of the lower sheet 6 is approximately three times the material thickness of the upper sheet 7. The lower sheet 6 is preferably made of aluminum. Hardened steel is also conceivable for higher strength requirements.

[0046] A structural sheet 8 is connected between the two sheets 6, 7. The two sheets 6, 7 are spaced apart from one another by the structural sheet 8. The structural sheet 8 is connected to both sheets 6, 7 in a manner resistant to shear, pressure, and tension. The structural sheet 8 is profiled in a meandering manner by means of U-shaped sections which are open toward the other side in an alternating manner. In its cross-sectional course shown in FIG. 3, the profile is formed from a repeating sequence F comprising a first contact section 9, a first bridging section 10, a second contact section 11, and a second bridging section 12. The first contact section 9 is connected to the lower sheet 6, namely by means of an adhesive 13 in the exemplary embodiment shown. The second contact section 11 is connected to the upper sheet 7 by a soldered connection. Both contact sections 9, 11 are connected to the respective sheet 6, 7 over their entire contact surface, consequently over the widths B1, B2 thereof, which are discernible in the cross-section thereof, and also over the length thereof.

[0047] The bridging sections 10, 12 connect the contact sections 9, 11, 9′ in the distance direction. For this purpose, they are arranged at right angles to the contact sections 9, 11. The first bridging section 10 is connected to the contact sections 9, 11, and the second bridging section 12 is connected to the second contact section 11 and first contact section 9′ of the following sequence of structural sections.

[0048] The bridging sections 10, 12 transition into the contact sections 9, 9′, 11 with a radius 14, 15, 16, 17 in each case. The radii 14, 15, 16, 17 are part of the bridging sections 10, 12 and are formed by the respective end sections of the bridging sections 10, 12. In the exemplary embodiment shown, there is a short, straight middle piece arranged at right angles to the sheets 6, 7, between radii 14, 15 or 16, 17, respectively, which are opposite one another in the thickness extension. This middle piece is arranged at right angles to the sheets 6, 7. The radii 14, 17 in the transition sections of the bridging sections 10, 12, which connect to the first contact sections 9, 9′, are designed with a larger radius than the radii 15, 16 with which the bridging sections 10, 12 adjoin the first contact sections 11.

[0049] The distance D between the upper sheet 7 and the lower sheet 6 is smaller than the smaller of the two different widths B1, B2 of the contact sections 9, 11. In the exemplary embodiment shown, the distance D corresponds to approximately half of width B1 of contact sections 11 and approximately one-third of width B2 of contact sections 9. This achieves a sandwich construction that is especially resistant to buckling.

[0050] In this exemplary embodiment, the hollow chambers 18, 18′ (FIG. 3) formed by the structural sheet 8 and the upper sheet 7 are used as temperature-control channels for conducting a temperature-control fluid in order to cool or heat the interior of the battery housing. In most cases, cooling should be the priority. For effective temperature control, the second contact sections 11 of the structural sheet 8 are connected to the upper sheet 7 by the soldered connections already described above. Due to the unequal width B1, B2 of the contact sections 9, 11 with contact sections 9 being wider in this regard, the hollow channels 18, 18′ have a larger cross-sectional area, so that a larger volume flow can be conveyed therethrough. It should be noted here that the thickness of the upper sheet 7 is about 1 mm and that of the lower sheet 6 is about 3 mm, and the distance D between the two sheets 6, 7 in the exemplary embodiment shown is about twice the thickness of the lower sheet 6 and thus is about 5 mm. Therefore, the above-described wider design of the hollow channels 18, 18′ is advantageous against the backdrop of the only slight free height available for increasing the through the hollow channels 18, 18′. The contact surface of the fluid conveyed through the hollow chambers 18, 18′ with the wall sections enclosing the hollow chambers 18, 18″ is correspondingly larger, and correspondingly more fluid can be conveyed through the hollow chambers 18, 18′. The adhesive 13 located between the first contact sections 9 and the lower sheet 6 prevents direct contact of the structural sheet 8 with the lower sheet 6. In this way, the structural sheet 8 is thermally insulated from the lower sheet 6, which also promotes the effectiveness of temperature control of the battery modules contained in the battery housing 1.

[0051] FIG. 4 shows a view from below of the battery housing 1. The lower sheet 6 is hidden to illustrate the following aspects in order to provide a clear view of the underside of the structural sheet 8. In the floor 3 shown in the figures, the two compartments separated by the longitudinal strut 4 for accommodating the battery modules are each connected to a coolant circuit. For the fluid connection, the parallel hollow chambers (18, 18′ in FIG. 3) are connected to each other by a respective hollow chamber connector 19, designed as a U-shaped connecting piece, namely as alternating adjacent hollow chambers, in order to convey fluid from an inlet 20 to an outlet 21, through the sandwich construction of the floor 3, in a meandering manner. The fluid path of the hollow channels is provided equally in the other half of the floor, namely from inlet 20.1 to outlet 21.1, through a corresponding arrangement of hollow chamber connectors 19.

[0052] FIG. 5 shows a further battery housing 1.1 in a view from below with the lower sheet hidden. The structural sheet 8.1 can be seen in a plan view. A plurality of support projections 22 are introduced into the structural sheet 8.1 by means of a deep-drawing process. The support projections 22 are offset with respect to one another in the manner of a grid in the longitudinal extension of the battery housing 1.1. As in the exemplary embodiment of FIGS. 1 to 4, the first contact sections 9.1, 9.1′ of the structural sheet 8.1 occupy a larger area than the second contact sections 11.1. In the exemplary embodiment shown, the second contact surface 11.1, which is formed by the upper side of the support projections 22, is significantly smaller than the first contact surface 9.1, 9.1′, This becomes especially clear from the detail of a cross-section shown in FIG. 6 along sectional line AA drawn in FIG. 5. The lower sheet 6.1 is also shown in this view. The upper sheet 7.1 and the structural sheet 8.1 can also be seen. The support projections 22 can be considered knob-like in this embodiment. The first contact section 9.1 is connected to the second contact section 11.1 via a first bridging section 10.1. The second contact section 11.1 is connected to the following first contact section 9.1′ via the second bridging section 12.1. In contrast to the exemplary embodiment in FIGS. 1 to 4, these two bridging sections 10.1, 12.1 are actually a single circumferential bridging section. In the cross-sectional view shown in FIG. 6, the sequence of sections consists of a first contact section 9.1, a first bridging section 10.1, a second contact section 11.1, and a second bridging section 12.1, as is also the case with the subject matter of the exemplary embodiment in FIGS. 1 to 4. This sequence repeats itself.

[0053] The hollow space formed between the upper sheet 7.1 and the structural sheet 8.1 can be used to conduct a temperature-control fluid. The temperature-control medium flows around the support projections 22.

[0054] FIG. 7 shows another embodiment of the battery housing 1.1 shown in FIGS. 5 and 6. In the case of the floor sandwich construction shown in FIG. 7 in a section of its cross-section, the support projections 22.1 are arranged in a tighter grid with respect to one another. In the cross-sectional view shown, in which the support projections 22.1 are shown at the maximum of the diameter thereof, the second contact sections 11.2 are significantly larger in diameter than the support projections 22 of the exemplary embodiment in FIG. 6. In addition, the angle of bridging sections 10.2, 12.2 corresponds to the angle occupied by bridging sections 10, 12 in relation to the lower and upper sheets 6, 7 in the embodiment of FIGS. 1 to 4. In contrast, the angle of bridging sections 10.1, 10.2 is smaller in the embodiment of FIGS. 5 and 6. The narrower the grid of the support projections 22, 22.1 is designed, the stiffer the floor sandwich construction.

[0055] In this embodiment, too, the structural sheet 8.2 is connected to the lower sheet 6.2 by adhesive 13.1. The structural sheet 8.2 is connected to the upper sheet 7.2 with a soldered joint. This takes place over the entire width of the respective contact sections 9.2, 9.2′, 11.2 resting against the sheets 6.2, 7.2, as has already been described for the exemplary embodiment in FIGS. 1 to 4.

[0056] The invention has been described on the basis of an exemplary embodiment. Without departing from the scope of protection, described by the claims, numerous further embodiments for implementing the concept of the invention are apparent to one skilled in the art, without these having to be explained in more detail at this juncture.

TABLE-US-00001 List of reference numerals  1, 1.1 Battery housing  2 Frame  3 Floor  4 Longitudinal strut  5 Cross strut  6, 6.1, 6.2 Lower sheet  7, 7.1, 7.2 Upper sheet  8, 8.1, 8.2 Structural sheet  9, 9′, 9.1, 9.1′, 9.2, 9.2′ First contact section 10, 10.1, 10.2 First bridging section 11, 11.1, 11.2 Second contact section 12, 12.1, 12.2 Second bridging section 13, 13.1 Adhesive 14, 14.1, 15, 15.1, 16, 16.1, 17, 17.1 Radius 18, 18′ Hollow chamber 19, 19.1 Hollow chamber connector 20, 20.1, 20.2 Inlet 21, 21.1 Outlet 22, 22.1 Support projection B1, B2 Width of contact sections D Distance F Sequence