Method for manufacturing a cell module for a high-voltage battery and a cell module as well as a high-voltage battery

Abstract

The invention relates to a cell module for a high-voltage battery with a module housing (4; 28) comprising module housing parts (6, 8, 10, 12, 14; 30, 32, 34, 36, 38) in the form of module housing cover (6; 30), module housing base (8; 32), module housing front, module housing rear (10; 34) and two module housing side surfaces (12, 14; 36, 38), in which a number of adjacently arranged cuboid battery cells (16) are provided, each of which has cell surface parts (18, 20, 22, 24, 26) in the form of cell cover (18), cell base (20), a cell front (22), cell rear and two cell side surfaces (24, 26), wherein at least two opposing module housing parts (12, 14; 30, 32) are convex, wherein the battery cells (16) are fixed in the module housing (4; 28) by a force closure acting on at least two cell surface parts (24, 26) due to a pre-tension of the convex module housing parts (12, 14; 30, 32).Furthermore, the invention relates to a method for manufacturing a cell module (2) and a high-voltage battery with at least one such cell module (2).

Description

[0001] The invention relates to a method for producing a cell module for a high-voltage battery. Furthermore, the invention relates to a cell module produced in this way and to a high-voltage battery comprising at least one such cell module.

[0002] The rise of electromobility has dramatically increased demand for high-voltage batteries. Important factors in the development of such high-voltage batteries are material costs, capacity, service life, and manufacturing and assembly costs. In this context, DE 10 2012 214 443 A1 discloses a high-voltage battery in which the stack of battery cells is secured in a module housing. The module housing is at least partially curved. This creates deformability in the module housing components, which, together with an additional pressure distribution medium, is intended to secure the battery cells. The assembly effort required to secure the battery cells is high and therefore expensive, making assembly of such cell modules complicated.Cell modules with battery cells that are secured by prestressing the cambered module housing parts are known from the prior art according to DE 10 2019 200 107 A1, KR 10 2022 116 815 A, DE 10 2012 214 443 A1, and DE 10 2020 131 528 A1. However, the production of such cell modules proves to be very complex and difficult.

[0003] The object of the invention is therefore to provide a method for producing a cell module that avoids the above-mentioned disadvantage in a simple and cost-effective manner.

[0004] This object is achieved by a method according to the invention in that in a first step the module housing is produced and at least two opposing module housing parts are cambered, in a second step the cambered module housing parts are loaded in such a way that the cambering of the respective module housing parts is eliminated, in a third step at least the battery cells are inserted into the module housing and the module housing is closed and in a fourth step the cambered module housing parts are relieved in such a way that a force connection is created between two cell surface parts. This makes it particularly easy to produce the cell module. Additional pressure distribution means can be omitted. In addition, concave or convex curvatures are almost eliminated, which benefits better use of installation space.

[0005] The object is also achieved by a cell module produced in this way, wherein module housing parts in the form of module housing cover, module housing base, module housing front, module housing rear and two module housing side surfaces, in which a number of cuboid battery cells arranged next to one another, each having cell surface parts in the form of cell cover, cell base, a cell front, cell rear and two cell side surfaces, are provided, wherein at least two opposite module housing parts are domed and are designed to be pullable apart or compressible, wherein the battery cells are fixed in the module housing due to a prestressing of the domed module housing parts by a frictional connection acting on at least two cell surface parts.

[0006] In a particularly advantageous embodiment, the force-fit connection to the cell surface parts is achieved by two opposing, concavely curved module housing parts. In this case, the curved module housing parts were pulled apart during assembly and released again after the battery cells were inserted, thus establishing a force-fit connection between the curved module housing parts and the adjacent cell surface parts.

[0007] In an alternative embodiment, the force-fit connection to the cell surface parts is achieved by at least two opposing module housing parts, which are arranged adjacent to at least two convexly curved module housing parts. In this case, the curved module housing parts were pressed together during assembly and released again after the battery cells were inserted, thus establishing a force-fit connection between the module housing parts adjacent to the curved module housing parts and the adjacent cell surface parts.

[0008] In an advantageous embodiment, each battery cell rests with at least one cell side surface against a cooling surface, wherein the cooling surface is part of a cooling arrangement.

[0009] Furthermore, the problem is solved by a high-voltage battery with at least one such cell module.

[0010] The invention is explained in more detail with reference to a drawing, in which Fig. 1a) - 1d) each show a schematic representation of a concavely cambered module housing part during different assembly steps, and Fig. 2a) - 2d) each show a schematic representation of a convexly cambered module housing part during different assembly steps.

[0011] The Fig. 1a) - 1d) show a schematic side view of a cell module 2 (see Fig. 1d) for a high-voltage battery (not shown in detail) in its initial state. The cell module 2 has Fig. 1a) a module housing 4 with module housing parts 6, 8, 10, 12 and 14 in the form of module housing cover 6, module housing base 8, module housing rear 10 and two module housing side surfaces 12, 14. The module housing front surface is not shown in the present view, since it is used for inserting battery cells 16 (see Fig. 1c)) was removed. The opposing module housing side surfaces 12, 14 are concavely curved in the first exemplary embodiment of a module housing 4 shown. In the next step, these opposing module housing side surfaces 12, 14 (see arrows) are subjected to tensile stress such that the curvature of the module housing side surfaces 12, 14 is essentially eliminated, thus providing a cuboid-shaped module housing 4.

[0012] Fig. 1c) now shows the cuboid module housing 4 after the insertion of five battery cells 16, each of which also has cell surface parts in the form of a cell cover 18, a cell base 20, a cell front 22, a cell rear, and two cell side surfaces 24, 26, which were designated by way of example based on the battery cell 16 facing the module housing side surface 14. In this case, the module housing side surfaces 12, 14 are still under load. Fig. 1d) now shows the module housing 4 in the unloaded state, wherein the module housing side surfaces 12, 14 deform concavely again, whereby a force connection is established between the module housing side surfaces 12, 14 and the cell side surfaces 24, 26 of the battery cells respectively adjacent to the module housing side surfaces 12, 14 and in this way the battery cells 16 are fixed in the module housing 4.

[0013] The characters Fig. 2a) - 2d) now show an alternative cell module 3 with a module housing 28, which has corresponding module housing parts 30, 32, 34, 36 and 38 in the form of module housing cover 30, module housing base 32, module housing rear 34 and two module housing side surfaces 36, 38. In contrast to the embodiment of the module housing 4 according to the Fig. 1a) - 1d) in the initial state, the opposing module housing cover surface 30 and the module housing base surface 32 are convexly cambered in order to form a cuboid module housing 28 according to Fig. 2b) to train. Fig. 2c) then shows the battery cells 16 inserted into the module housing 28 and Fig. 2d) the module housing 28 without load, whereby the force connection of the module housing side surfaces 36, 38 with the corresponding cell side surfaces 24, 26 is established.

[0014] A method according to the invention can now be described as follows. In a first step, the module housing 4; 28 is produced, wherein at least two opposite module housing parts 12, 14; 30, 32 are cambered. In a second step, the cambered module housing parts 12, 14; 30, 32 are loaded in such a way that the cambering of the respective module housing parts 12, 14; 30, 32 is removed. In a third step, at least the battery cells 16 are inserted into the module housing 4; 28 and the module housing 24; 28 is closed. In a fourth step, the cambered module housing parts 12, 14; 30, 32 are then relieved of load in such a way that a force connection is established between two cell surface parts 24, 26.

[0015] Finally, it should be noted that each battery cell 16 can also have at least one cell side surface 24, 26 in contact with a cooling surface, wherein the cooling surface is part of a cooling arrangement. However, this embodiment is not shown in the drawing.

Claims

[1] Method for producing a cell module for a high-voltage battery, characterized by in that in a first step a module housing (4; 28) is produced and at least two opposite module housing parts (12, 14; 30, 32) are cambered, in that in a second step the cambered module housing parts (12, 14; 30, 32) are loaded in such a way that the cambering of the respective module housing parts (12, 14; 30, 32) is removed, in that in a third step at least battery cells (16) are inserted into the module housing (4; 28) and the module housing (4; 28) is closed and in that in a fourth step the cambered module housing parts (12, 14; 30, 32) are relieved of load in such a way that a force connection to two cell surface parts (24, 26) is produced. [2] Cell module for a high-voltage battery with a module housing (4; 28) produced by a method according to claim 1, characterized bythat module housing parts (6, 8, 10, 12, 14; 30, 32, 34, 36, 38) in the form of module housing cover (6; 30), module housing base (8; 32), module housing front, module housing rear (10; 34) and two module housing side surfaces (12, 14; 36, 38), in which a number of adjacently arranged cuboid battery cells (16), each having cell surface parts (18, 20, 22, 24, 26) in the form of cell cover (18), cell base (20), a cell front (22), cell rear and two cell side surfaces (24, 26), wherein at least two opposite module housing parts (12, 14; 30, 32) are cambered and designed to be extendable or compressible, wherein the Battery cells (16) are fixed in the module housing (4; 28) due to a pre-tension of the cambered module housing parts (12, 14; 30, 32) by a force-lock acting on at least two cell surface parts (24, 26). [3] Cell module according to claim 2, characterized bythat the force connection to the cell surface parts (24, 26) takes place through two opposite, concavely cambered module housing parts (12, 14). [4] Cell module according to claim 3, characterized by that the force connection to the cell surface parts (24, 26) takes place through at least two opposite module housing parts which are arranged adjacent to at least two convexly cambered module housing parts (30, 32). [5] Cell module according to one of claims 2-4, characterized by that each battery cell (16) rests with at least one cell side surface (24, 26) against a cooling surface, wherein the cooling surface is part of a cooling arrangement. [6] High-voltage battery with at least one cell module (2) according to one of the preceding claims 2-5.

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