HOUSING FOR THE CELL STACK OF A BATTERY

Abstract

The invention relates to a housing for a cell stack of a battery, comprising: an integral frame from accommodating the cell stack, wherein the frame surrounds at least three end faces of a cell stack which is accommodated in the housing, and at least one electrically conductive connecting element for establishing an electrical connection between an external connection and a cell stack which is accommodated in the housing is integrated in the frame; and a cover for covering sides, in particular all sides, of a cell stack which is received in the housing, which sides are not surrounded by the frame.

Claims

1. A housing (1) for a cell stack (2) of a battery, comprising: an integral frame (3) for accommodating the cell stack; wherein the frame surrounds at least three end faces of a cell stack which is accommodated in the housing, and at least one electrically conductive connecting element (12) for establishing an electrical connection between an external connection and a cell stack which is accommodated in the housing is integrated in the frame; and a cover (6) for covering all sides of the cell stack accommodated in the housing which are not enclosed by the frame.

2. A housing (1) according to claim 1, wherein the frame (3) is formed of plastic or a metal, in particular aluminium or high-alloy steel.

3. A housing (1) according to claim 1, comprising a base plate (5), the frame (3) extending along the outer edge of the base plate, so that by means of the base plate and the frame a recess (7) is formed for accommodating a cell stack (2), wherein the frame surrounds all four end faces of a cell stack which is accommodated in the housing and the base plate covers an underside of a cell stack which is accommodated in the housing.

4. A housing (1) according to claim 3, wherein the frame (3) and the base plate (5) are integrally designed.

5. A housing (1) according to claim 1, wherein the cover (6) is fixed, in particular glued, welded or sealed, to an upper side of the frame (3).

6. A housing (1) according to claim 1, comprising two cell poles (8), which are integrated in the frame (3) and allow an electrical connection to an external battery module, wherein for each cell pole the electrically conductive connection element (12) is provided for producing an electrical connection between the cell pole and a cell stack (2) accommodated in the housing, and wherein each of the connection elements is integrated in the frame and/or extends within the frame, in particular along an end face of a cell stack accommodated in the housing, from the corresponding cell pole up to a diverter (4) on a cell stack accommodated in the housing.

7. A housing (1) according to claim 6, wherein at least in some sections, the connection element (12) is mechanically compliant, in particular with regard to torsion, bending and/or tension and compression.

8. A housing (1) according to claim 6, wherein at least in some sections, the connection element (12) has clearance within a cavity (13) in the frame (3).

9. A housing (1) according to claim 6, wherein the connection element (12) comprises at least one conductive sliding sleeve and/or at least one conductive swivel bearing.

10. A housing (1) according to claim 1, wherein at least one sensor, in particular a pressure or temperature sensor, and/or at least one cooling channel, in particular a heat-pipe, is integrated in the frame (3).

11. A housing (1) according to claim 1, wherein the cover (6) is formed by a plastic or metal plate, in particular an aluminium plate, or a plastic or metal profile, in particular an aluminium profile, or a form-flexible plastic-metal composite foil, in particular a plastic-aluminium composite foil, or of Kevlar.

12. A housing (1) according to claim 1, wherein the frame (3) comprises a rectangular cross-section, which is designed as a full profile or hollow profile with or without ribbed structures.

13. A housing (1) according to claim 1, comprising two cell poles (8) which are integrated in the frame (3), wherein the cell poles are arranged on the same side or on opposite sides of the frame.

14. A method for producing a battery cell having a housing according to claim 1, said method comprising: form-fitting arrangement of a cell stack in the frame, so that the frame surrounds at least three end faces of the cell stack; and placement of the cover on the frame on sides, in particular all sides of the cell stack, which are not enclosed by the frame.

15. A method according to claim 14, wherein the frame is produced as an injection moulded component with an integrated conductor track (Moulded Interconnected Device, MID).

Description

[0043] Hereafter, exemplary embodiments of the invention are described in greater detail by reference to the drawings. They show, in schematic representation:

[0044] FIG. 1 a housing for a cell stack of a battery according to two designs of the present invention;

[0045] FIG. 2 a cross-section through the housing of FIG. 1;

[0046] FIG. 3 a housing for a cell stack of a battery according to a further design of the present invention;

[0047] FIG. 4 a housing for a cell stack of a battery according to a further design of the present invention; and

[0048] FIG. 5 a connection element for a housing according to FIG. 4, for producing an electrical connection between a cell pole and a cell stack which is accommodated in the housing.

[0049] FIG. 1 shows a plan view of a housing 1 for a cell stack 2 of a battery in two different designs. The housing 1 comprises an integral frame 3 for accommodating the cell stack 2, wherein in the design shown on the left the frame 3 surrounds three end faces of the cell stack 2, while in the design shown on the right the frame 3 surrounds all four outer end faces of the cell stack 2.

[0050] FIG. 2 shows a cross section through the housing 1 in accordance with FIG. 1. It can be seen there that the frame 3, in contrast to housings according to the prior art, is not designed as a thin-walled container but rather has a rectangular cross-section. A height h of the frame 3 substantially corresponds to the height of the cell stack 2. A width b of the frame 3 is greater than the width of the cell stack 2 with a diverter 4.

[0051] The cross-section of the frame 3 can be designed, as shown, as a solid profile. For the purposes of weight reduction however, in alternative versions the frame 3 can also be designed as a hollow profile or with ribbed structures. The frame preferably consists of plastic.

[0052] FIG. 3 shows a housing 1 according to a further design of the present invention. In this design the frame 3 surrounds all four outer end faces of a cell stack 2 accommodated in the housing 1. In addition, the four-sided frame 3 comprises an integrated base plate 5.

[0053] FIG. 3 shows the housing 1 in three different states. At the top left the housing 1 is shown with cell stack 2 accommodated therein, wherein the side of the housing 1 at the top of FIG. 3 is formed by means of a cover 6, which rests on the frame 3 and covers the cell stack 2 located in the housing 1.

[0054] On the right next to it, the housing 1 is shown with the cover 6 removed.

[0055] At the top right of FIG. 3 the housing 1 is shown without cover 6 and without cell stack 2. As can be seen here, the frame together with the base plate 5 forms a recess or cavity 7, into which the cell stack 2 can be inserted in a form-fitting manner.

[0056] The lower section of FIG. 3 shows a cross section of the housing 1 with cell stack 2 and cover 6.

[0057] The housing 1 comprises cell poles 8, which are arranged on opposite outer end faces of the housing 1. In an alternative design the poles 8 can also be arranged on the same end face of the housing 1. The cell poles 8 comprise electrically conductive extensions 9, which protrude into the interior of the housing, in particular into the recess 7. The diverters 4 of a cell pole 2 which is inserted into the housing 1 come to rest on these extensions 9, as can be easily identified in particular in cross-section through the housing 1.

[0058] This design has the advantage that, after inserting the cell stack 2 into the recess 7, the housing 1 is still open so that the process of filling with electrolyte is facilitated.

[0059] FIG. 4 shows a housing 1 for a cell stack of a battery in accordance with a further design of the present invention. In this design the two cell poles 8 are arranged on one side of the housing 1 (in the image orientation, the upper side). In the lower section of the housing 1, in each case one electrical connection 10 for the cell stack 2 is integrated into the frame 3 on opposite sides. The electrical connections 10 are electrically connected to the respective cell poles 8, wherein the electrical connection extends within the frame 3 and is integrated therein. The electrical connection 10 is connected to the diverters 4 of a cell stack 2 contained in the housing 1, so that an electrical connection between the cell poles 8 and the cell stack 2 is made.

[0060] FIG. 5 shows a component 11, by means of which the electrical connection between the cell poles 8 and the cell stack 2 can be made. The component 11 can be integrated in the frame 3 of the housing 1. The upper end of the component 11 is formed by the cell poles 8. From the cell poles 8, an electrically conductive and mechanically compliant connecting element 12 extends up to the electrical connection 10. In the region of the electrical connection 10, the connecting element 12 extends in the direction of the interior of the housing 1 and thus forms one of the extensions 9 shown in FIG. 3 for contacting to a diverter 4 of the cell stack 2.

[0061] The region of the electrical connection 10 can be arranged at any desired level of the cell stack 2. In the design shown in FIGS. 4 and 5 the cell poles 8 are located on an (upper) end face of the housing 1, while the electrical connection 10 is arranged closer to the opposite (lower) end face of the housing 1.

[0062] The connecting element 12 extends within a cavity 13 in the frame 3. Inside the hollow space 13 the connection element 12 has a predefined amount of clearance, so that forces acting on the cell poles 8 can be compensated for by movement of the connection element 12 within the cavity 13.

[0063] At various points the component 11 comprises electrical insulations or seals, which fix the connection element 12 within the frame 3 and electrically insulate it from the cell stack 2.

[0064] The component 11 enables a separation of the functions “electrical contacting to the battery module” from the other functions, in particular the functions “insulation”, “sealing”, “positioning of the cell stack” and “electrical contacting of the cell stack”. The poles 8, as the carrier of the function “electrical contacting to the battery module”, can have kinematic degrees of freedom. The bridging of the spatially separated functional units is carried out with electrically conductive connection elements. These can implement additional functions, e.g. safety functions using over-current resistors and the like. The connection elements can have kinematic degrees of freedom, either inherent to the components, for example due to their geometrical shape, or due to additional elements, such as conductive swivel bearings or sliding sleeves. In particular, the connection elements can have a defined mechanical compliance with regard to torsion, bending or axial tension/compression. This compliance can be adjusted by the design of the connection to the named functional units, either by their geometry or by their material. The connection elements can consist of different materials.

[0065] Due to the invention, depending on the particular design, the following benefits are obtained: [0066] Due to the separation of the functional units the poles of the cell housing can be designed to be movable while maintaining the sealed property of the cell. This means that relative movements (arising from the operation/from the assembly/due to the length expansion) between the cells and their parent structure do not act, or at least only in a weakened form, on the cell poles or on the cell stack and the seals and insulations in the form of forces and moments. [0067] The parallelization of the horizontally viewed arrangement of housing/diverter/diverter terminals—cell stack—diverter terminals/diverter/housing leads to a better utilization of the available space in the housing and thus to an increase in the volumetric energy density, which is valuable in electric vehicles. [0068] The arrangement of the cell seals and insulations in the housing, as shown in FIG. 5, also leads to a higher utilization of the available installation space, or to more installation space, for integrating the seals and insulations. Accordingly, the use of less expensive or better functioning components is enabled. [0069] The arrangement of the seals and insulations in the chassis allows these to be spatially separated from the weld seam between the cover and housing and therefore reduces the risk of damage to the seals and insulations during the joining process. [0070] With the invention the cell height in the housing can be precisely adjusted in the housing pre-assembly (e.g. by vertical displacement of the terminals on the diverter before the joining process). In contrast to housings according to the prior art, the cell height is then no longer affected in the cell assembly. This results in less waste due to rejects in the cell assembly, and to significantly lower vertical manufacturing tolerances, which brings with it significant advantages in the module assembly. [0071] The manufacturing tolerances in the horizontal plane can be compensated for by the mobility of the cell poles. Thus, in spite of variations in the housing geometry the module assembly is made significantly easier.

LIST OF REFERENCE NUMERALS

[0072] 1 housing [0073] 2 cell stack [0074] 3 frame [0075] 4 diverter [0076] 5 base plate [0077] 6 cover [0078] 7 recess [0079] 8 cell poles [0080] 9 extensions of the cell poles [0081] 10 electrical connection [0082] 11 component [0083] 12 connection element [0084] 13 cavity [0085] 14 insulations