MODULE HOUSING ASSEMBLY, BATTERY MODULE, AND METHOD FOR CLAMPING A BATTERY MODULE

Abstract

A module housing assembly for accommodating at least one battery cell, including a module housing with a housing base, which delimits a receiving area for accommodating the at least one battery cell with respect to a first direction, and two side plates, which delimit the receiving area on both sides with respect to a second direction. The module housing assembly additionally including a retaining element for arrangement on the at least one battery cell accommodated in the receiving area, and a clamping device, which extends at least from a first of the side plates to a second of the side plates on a side of the receiving area opposite the housing base, wherein the clamping device is designed in such a way that the clamping device can exert a force on the retaining element in the direction of the housing base, if said retaining element is arranged on the at least one battery cell arranged in the receiving area.

Claims

1. A module housing assembly for accommodating at least one battery cell, wherein the module housing assembly comprises: a module housing with a housing base, which delimits a receiving area for accommodating the at least one battery cell with respect to a first direction, and two side plates, which delimit the receiving area on both sides with respect to a second direction; wherein the module housing assembly includes; a retaining element for arrangement on the at least one battery cell accommodated in the receiving area, so that at least a first part of the retaining element delimits the receiving area with respect to the first direction on a side of the receiving area opposite the housing base; and a clamping device, which extends at least from a first of the side plates to a second of the side plates on a side of the receiving area opposite the housing base, wherein the clamping device is designed in such a way that the clamping device can exert a force on the retaining element in a direction of the housing base, if said retaining element is arranged on the at least one battery cell arranged in the receiving area.

2. The Module housing assembly according to claim 1, wherein the housing base is designed as a cooling base.

3. The Module housing assembly according to claim 1, wherein the retaining element has a thickness with respect to the first direction which varies along the second direction, in particular which decreases in the direction of the respective side plates starting from a center of the retaining element with respect to the second direction.

4. The Module housing assembly according to claim 1, wherein the retaining element has two side tabs which adjoin the first part of the retaining element on both sides in the second direction and extend in the direction of the housing base and which, when the at least one battery cell is accommodated in the receiving area, are each arranged between the at least one battery cell and one of the respective side plates.

5. The Module housing assembly according to claim 1, wherein the retaining element comprises a metal and/or a plastic and/or is provided as a hybrid component which in particular has an at least partially elastic component.

6. The Module housing assembly according to claim 1, wherein the clamping device is designed as at least one tensioning strap, in particular wherein the at least one tensioning strap has a fiber composite plastic; and/or has a carbon-fiber strap or is designed as such; and/or has a metal or is designed as a metal strap.

7. The Module housing assembly according to claim 1, wherein the module housing is mostly formed from a plastic, in particular a fiber-reinforced plastic, and/or comprises a metal or an alloy.

8. The Module housing assembly according to claim 1, wherein the clamping device and/or the retaining element has at least one releasable passage opening assigned to a releasable degassing opening of the at least one battery cell, which passage opening is arranged in the first direction above the degassing opening of the at least one battery cell, in particular when the at least one battery cell is accommodated in the receiving area.

9. A Battery module with a module housing assembly according to claim 1 and at least one battery cell accommodated in the receiving area.

10. A Method for clamping a battery module, which has a module housing assembly that comprises a module housing with a housing base, which delimits a receiving area for accommodating at least one battery cell in a first direction, and two side plates, which delimit the receiving area on both sides in a second direction, wherein that a retaining element is arranged on the at least one battery cell, so that, when the at least one battery cell is arranged in the receiving area, at least a first part of the retaining element delimits the receiving area in the first direction on a side of the receiving area opposite the housing base, and a clamping device is provided, which extends at least from a first of the side plates to a second of the side plates on a side of the receiving area opposite the housing base, and which is clamped in such a way that the clamping device exerts a force on the retaining element in a direction of the housing base, if said retaining element is arranged on the at least one battery cell arranged in the receiving area.

11. The Module housing assembly according to claim 2, wherein the retaining element has a thickness with respect to the first direction which varies along the second direction, in particular which decreases in the direction of the respective side plates starting from a center of the retaining element with respect to the second direction.

12. The Module housing assembly according to claim 2, wherein the retaining element has two side tabs which adjoin the first part of the retaining element on both sides in the second direction and extend in the direction of the housing base and which, when the at least one battery cell is accommodated in the receiving area, are each arranged between the at least one battery cell and one of the respective side plates.

13. The Module housing assembly according to claim 3, wherein the retaining element has two side tabs which adjoin the first part of the retaining element on both sides in the second direction and extend in the direction of the housing base and which, when the at least one battery cell is accommodated in the receiving area, are each arranged between the at least one battery cell and one of the respective side plates.

14. The Module housing assembly according to claim 2, wherein the retaining element comprises a metal and/or a plastic and/or is provided as a hybrid component which in particular has an at least partially elastic component.

15. The Module housing assembly according to claim 3, wherein the retaining element has a thickness with respect to the first direction which varies along the second direction, in particular which decreases in the direction of the respective side plates starting from a center of the retaining element with respect to the second direction.

16. The Module housing assembly according to claim 4, wherein the retaining element comprises a metal and/or a plastic and/or is provided as a hybrid component which in particular has an at least partially elastic component.

17. The Module housing assembly according to claim 2, wherein the clamping device is designed as at least one tensioning strap, in particular wherein the at least one tensioning strap has a fiber composite plastic; and/or has a carbon-fiber strap or is designed as such; and/or has a metal or is designed as a metal strap.

18. The Module housing assembly according to claim 3, wherein the clamping device is designed as at least one tensioning strap, in particular wherein the at least one tensioning strap has a fiber composite plastic; and/or has a carbon-fiber strap or is designed as such; and/or has a metal or is designed as a metal strap.

19. The Module housing assembly according to claim 4, wherein the clamping device is designed as at least one tensioning strap, in particular wherein the at least one tensioning strap has a fiber composite plastic; and/or has a carbon-fiber strap or is designed as such; and/or has a metal or is designed as a metal strap.

20. The Module housing assembly according to claim 5, wherein the clamping device is designed as at least one tensioning strap, in particular wherein the at least one tensioning strap has a fiber composite plastic; and/or has a carbon-fiber strap or is designed as such; and/or has a metal or is designed as a metal strap.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Exemplary embodiments of the disclosure are described hereinafter. The following is shown:

[0034] FIG. 1 a schematic exploded view of a battery module according to an example which is not part of the disclosure;

[0035] FIG. 2 a schematic view of a battery module with a battery module housing assembly according to an exemplary embodiment of the disclosure;

[0036] FIG. 3 a schematic and perspective view of a part of the module housing assembly according to an exemplary embodiment of the disclosure;

[0037] FIG. 4 a schematic representation of a plan view of a part of a tensioning strap with a releasable degassing opening according to an exemplary embodiment of the disclosure;

[0038] FIG. 5 a schematic representation of a part of a tensioning strap with a releasable degassing opening according to a further exemplary embodiment of the disclosure;

[0039] FIG. 6 a schematic representation of a part of a battery module in three different degassing states according to an exemplary embodiment of the disclosure.

DETAILED DESCRIPTION

[0040] The exemplary embodiments explained hereinafter are preferred embodiments of the disclosure. In the exemplary embodiments, the described components of the embodiments each represent individual features of the disclosure to be considered independently of one another, which each also refine the disclosure independently of one another. Therefore, the disclosure is also intended to comprise combinations of the features of the embodiments other than those shown. Furthermore, the described embodiments can also be supplemented by further ones of the above-described features of the disclosure.

[0041] In the figures, the same reference signs designate elements that have the same function.

[0042] FIG. 1shows a schematic exploded view of a battery module 10 according to an example which is not part of the disclosure. In this case, the battery module has a cell stack 12 with several battery cells 14, of which only one is provided with a reference numeral for reasons of clarity. The battery cells 14 can be separated from one another by separating elements for electrical and/or thermal decoupling. Such a cell stack 12 is also delimited on both sides by respective end plates 18, into which further components 20, such as electronic components, can be integrated externally. In order to clamp the battery cells 14 together in the x-direction, the end plates 16 are connected to one another and clamped via side binders 22. Insulation inserts 24 can be introduced between the side binders 22 and the cell stack 12. The side binders 22 usually have a chamfer 22a on the upper edge so that the cells 14 do not fall out of the module 10 when subjected to loads in the z-direction. Further components can then be placed on the module, such as electrical interconnection components 26 and a module cover 28. Overall, such a module 10 is therefore composed of numerous different parts. This has clear disadvantages, especially with regard to preloading of the cells, because the forces cannot be optimally dissipated and the structures are not as stiff as a highly integrated structure, for example. In addition, numerous work steps are necessary in assembly, in which individual parts must be joined together.

[0043] These disadvantages can now be advantageously avoided by the disclosure or the embodiments thereof.

[0044] FIG. 2 shows schematic view of a battery module 30 with a module housing assembly 32 according to an exemplary embodiment of the disclosure. The module housing assembly 32 in this case is preferably in the form of a fully integrated plastic module, although it is also conceivable to use metal housing components. Basically, this module housing assembly 32 initially comprises a module housing 34 which in turn comprises a housing base 36 and two side plates 38. The module housing 34 has a receiving area 40 in which, in this example, a cell stack 42 with several battery cells 46 arranged next to one another in the x-direction is accommodated. The side plates 38 delimit the receiving area 40 in the x-direction, while the housing base 36 is arranged on the lower side of the receiving area 40 and thus delimits the receiving area 40 downwards, i.e. opposite the shown z-direction. The housing 34 can be designed to be open in the y-direction.The side plates 38 are preferably aligned perpendicularly to the housing base 36 and are attached thereto. Optionally, these side plates can also be designed in one piece with the base. Since the pressure plates provided by the side plates 38 and the base plate, i.e. the housing base 36, are a fixed unit and there are no welded joints, the modules 30 can be built significantly more rigidly. In addition, fewer parts have to be joined and assembled in production. A design made of a plastic or a plastic composite material, for example a fiber-reinforced plastic, also has the great advantage that no additional insulation elements and inserts have to be provided between the cell stack 42 and the housing components 36, 38. The housing base 36 is also preferably designed as a cooling base, that is to say it can have cooling channels through which a coolant can flow, which are not shown here, however. The cell cooling can thus be integrated directly into the module 30. To clamp the battery cells 46 in the x-direction and at the same time to press the battery cells 46 opposite the z-direction, the module housing assembly 32 also has a clamping device in the form of a tensioning strap 44 and a retaining element 48. The retaining element 48 or at least a part 48a thereof is arranged on the cell stack 42 on a side opposite the housing base 36. Optionally, this retaining element 48 can also have two second parts 48b, which can be provided in the form of tabs 48b, which are arranged or clamped between the side plates 38 and the cell stack 42. Thus, the retaining element 48 is optionally inserted into the lateral pressure plates 38, i.e. the side plates 38, or between the side plates 38 and the cell stack 42. However, the retaining element 48 can also consist solely of the aforementioned first part 48a. The tensioning strap 44 completely surrounds the module housing assembly 32 with the cell stack 42 accommodated therein and can, for example, be fastened to one of the side plates 38 in a fastening region 50. The side plates 38 in this case can also be provided with a small groove that extends in the y-direction and through which the tensioning strap 44, which is preferably designed as a tape, is pulled so that it can be tightened during assembly to clamp the tensioning strap 44. After the tensioning strap has been clamped, this groove can be filled with injection molding, for example, in order to attach the tape 44 to the side plate 38. This creates a kind of wedge effect.

[0045] Since this tape 44 extends above the battery cells 46 in combination with the retaining element 48, the cells 46 can be prevented from lifting off in the z-direction. However, it is especially advantageous that this tensioning strap 44, in combination with the retaining element 48, which provides a hold-down device, can also be used to exert a pressing force downwards on the battery cells 46, opposite the z-direction, in the direction of the housing base 36. This pressing force on the respective cells 46 is denoted by F in the present case. This results from an initial force F0,which is exerted on the hold-down devices 48 via the tensioning strap 44. Furthermore, the retaining element 48 has a thickness d in the z-direction, which varies in the x-direction. In particular, the retaining element 48 is thicker in the center 52 thereof with respect to the x-direction than in the edge region 54 near the side plates 38. The retaining element 48 therefore has a different wall thickness on the outside 54 than in the center 52 of the component 48. This makes it possible for the pressing forces F to be distributed almost homogeneously on the cells 46 over the entire x-direction. These can thus advantageously be pressed evenly against the cooling base 36. As a result of these pressing forces F, a gap filler between the cells 46 and the cooling base 36 can also be dispensed with. This allows a significantly more efficient connection to the cooling base 36. Since a base 36 is integrated into the module 30, which base serves as a cooling base 36 at the same time, advantageously no further effort is required for gap fillers or bases integrated into the battery housing. In addition, crash structures 56 can also be easily integrated into the base 36, which can be accomplished especially easily if the base 36 or the housing 34 is made of plastic. In the present example, these crash structures 56 are shown only schematically with dashed lines. These structures can be provided, for example, as a kind of edge or protruding elevation relative to the base plane of the housing base 36.

[0046] FIG. 3 again shows a schematic representation of a part of the module housing assembly 32, in particular without the hold-down device 48 and the housing base 36, and without the cells 46 accommodated in the receiving area 40. In particular, the two side plates 38 are shown here with the tensioning strap 44, in particular to illustrate the clamping process. The ends 44a of the tensioning strap 44 can be passed through eyelets on one of the side plates 38 in a fastening region 50, which eyelets form, for example, a 45 degree angle with the x- and z-direction. This allows clamping of the tensioning strap 44 by pulling 58 on the ends 44a in the y-directionas shown. The tightening is indicated by the arrows 58. If the tensioning strap 44 is sufficiently clamped, the eyelet area in the fastening region 50 can be filled with plastic and the tensioning strap 44 can thus be cast in the fastening region with the side plate 38.

[0047] The pressure F on the cells 46 can be set opposite the z-direction by means of the tensioning force of the tensioning strap 44 in combination with the variable thickness d of the retaining element 48. The retaining element 48 coupled to the tensioning strap 44 thus advantageously allows an additional compressive force from the tensile force of the strap 44 to be applied to the cells 46.

[0048] If the tape 44 extends between the terminals of the battery cells 46, which can be arranged on the respective upper sides 46a of the battery cells 46 (see FIG. 2), it is preferred that the tape 44 has openings or at least fully or partially stamped or cut or cut-through areas to provide releasable openings. These are shown as examples in FIGS. 4 and 5 in a plan view of the tape 44. Such a releasable opening 60 is formed by a U-shaped cut, through-cut, stamping, or perforation in the tensioning strap 44 in FIG. 4, and it is formed as a straight cut or through-cut or perforation or stamping in FIG. 5. If gas emerges from the battery cells 46, these openings 60 open at the predetermined breaking points provided in this way, as a result of which the gas can escape. This is shown schematically in FIG. 6 in a side view for three different degassing states. The different states are denoted by Z1,Z2, and Z3. A battery cell 46 is shown in particular as well as the overlying combination of retaining element 48 and tape 44 for a respective state Z1,Z2, Z3. The first state Z1 shows the cell 46 in the normal operating state, in which no outgassing takes place. A releasable degassing opening 62 assigned to the upper side of the cell 46 is closed here, as is the releasable degassing opening 60 of the tape 44. In the second state Z2, the cell 46 begins to degas and puts pressure onto the bursting element 60 of the cell 46. This allows gas 64 to escape from the cell 46. In state Z3, the cell 46 degasses even more and the gas flow 64 is guided in a targeted manner through the torn strap section of the tape 44, which can come into contact with or be supported on, for example, an overlying plate, for example a housing cover. Optionally, a gas-routing channel can also be integrated into the hold-down device 48 or passage openings arranged extending in the z-direction over the bursting membranes 60 of the cells 46.

[0049] Overall, the examples show how the disclosure can provide a retaining element in the z-direction, which allows efficient formation of a battery module with a retaining element, which in turn contains or provides a homogeneous load distribution due to the deformation or geometry of the retaining element. The entire module can be made of plastic and designed to be highly integrated. Such a module can be significantly lighter, since tapes acting as a tensioning strap are very light. Overall, a cost saving of 10 to 15 percent can be achieved. Above all, the provision of a significantly simpler module housing without costly cooling is made possible as well as a module completely free of gap filler.