DE102022004064A1 - Battery module and method for assembling it and battery - Google Patents

Abstract

The invention relates to a battery module (1), comprising a module housing (2) with cylindrical cavities (3) for accommodating individual battery cells (4) with cylindrical cell housings (5), the cylindrical cavities (3) having a larger diameter (D) than the cylindrical cell housing (5), wherein a fixation is provided between the module housing (2) and the respective cell housing (5), which holds the respective cell housing (5) in a vertical direction (z) perpendicular to a transverse direction (x) and The plane spanning the longitudinal direction (y) is fixed relative to the module housing (2). The battery module according to the invention is characterized in that the fixation is designed as a mechanical positioning contour (8), which comprises a plurality of sections (11) along a circumference of each cell housing (5), which hold the cell housing (5) relative to the respective cylindrical cavity (3). Fix the module housing (2) in such a way that the cell housings (5) are fixed in the transverse direction (x) and in the longitudinal direction (y) in both directions and in the height direction (z) in at least one direction, with at least one along the circumference Opening (12) remains, through which a gap 6 between the walls of the cylindrical cavity (3) and the cell housing (5) is accessible. According to the method, the individual battery cells (4) can be glued to the module housing (2) in a later production step.

Description

The invention relates to a battery module according to the type defined in more detail in the preamble of claim 1. The invention also relates to a method for assembling such a battery module. The invention also relates to a battery with at least two such battery modules.

Battery modules, which combine several individual battery cells in a module housing, are known from the prior art. The generic state of the art is essentially described here EP 3 419 079 A1 , which shows a type of module housing that has through openings into which individual battery cells with a cylindrical cell housing are inserted. These are positioned accordingly in a height direction as well as in longitudinal and transverse directions perpendicular thereto and fixed in the housing via a fixation by gluing. This is very complex because the individual battery cells have to be reliably held in position until they are glued, for which no information is given in the document mentioned. In addition, subsequent contacting is critical because, for example, when cell connectors are welded on, undesirable mechanical stresses can occur due to the existing adhesive connection.

For further prior art, reference can also be made to a module housing through which cooling air flows, in which cylindrical individual battery cells are fixed via projections in channels through which air flows. This structure is in the US 2022/0077522 A1 described.

Furthermore, the further state of the art can be referred to EP 3 748 714 A1 to get expelled. This shows a battery pack with two cylindrical individual battery cells, which are designed in a module housing for inclusion in a laptop, for example.

The object of the present invention is to provide an improved battery module as well as a method for assembling it and a battery constructed from it.

According to the invention, this object is achieved by a battery module with the features in claim 1, and here in particular in the characterizing part of claim 1. Advantageous refinements and further developments result from the dependent claims. In addition, a method with the features in claim 8 solves the problem. Here too, an advantageous development results from the dependent subclaim. Claim 10 describes a battery made of such battery modules, which also solves the problem.

In the case of the battery module according to the invention, it comprises a module housing with cylindrical cavities for accommodating individual battery cells. These individual battery cells are similar to the prior art in cylindrical cell housings, which are accommodated in cylindrical cavities. There is a fixation between the module housing and the respective cell housing, which fixes the respective cell housing in a height direction in a transverse direction perpendicular to it and in a longitudinal direction perpendicular to these two directions relative to the module housing. This fixation, which is formed by gluing in the prior art mentioned at the outset, is now designed in the battery module according to the invention as a mechanical positioning contour, which comprises several sections along a circumference of the respective cell housing, which hold the cell housing relative to the cavity of the module housing in the Fix in such a way that the cell housings are fixed in the transverse direction and in the longitudinal direction in both directions and in the height direction in at least one direction, with at least one opening remaining along the circumference, through which the volume or the gap between the walls of the cylindrical cavity and the cell housing is accessible.

Unlike in the prior art, the cell housings are not glued directly to the module housing. Rather, they are securely fixed via a mechanical positioning contour in the transverse direction and the longitudinal direction, which are typically perpendicular to a central axis of the cylindrical shape of both the cell housing and the cavity. In the height direction, the fixation takes place in at least one direction, so the cell housings can, for example, be suspended in the cavities in the direction of gravity and are fixed via the positioning contour in such a way that they do not go further into the cavities in this height direction than specified by the positioning contour protrude in.

The volume between the walls of the cylindrical cavity and the cell housing is then accessible via the at least one opening, so that in a later production step an adhesive can be introduced between the walls of the cavity and the cell housing via this at least one opening. Until then, however, the individual cell housings are in any case sufficiently firmly fixed via the positioning contour to go through further manufacturing steps in which the individual battery cells are, for example, within the module housing via welded-on cell connectors binders can be contacted electrically or the like.

According to an extremely favorable development of the battery module according to the invention, it can be provided that the positioning contour has a plurality of sections, preferably evenly distributed over the circumference, with a greater radial extent than the sections in between. The positioning contour can therefore, for example, have two or more parts in which it is suitable for establishing contact between the battery cell or between the cell housing and the module housing in order to allow the aforementioned fixation. The areas arranged between them with a smaller radial extent then create the at least one opening in order to make the volume or the gap between the walls of the cylindrical cavity and the cell housing accessible.

A further very favorable embodiment of the battery module according to the invention further provides that the positioning contour is made of electrically insulating material. Such a design made of electrically insulating material allows the use of conventional cell housings, which consist, for example, of deep-drawn aluminum cups and at the same time form one of the poles, typically the negative pole of the individual battery cell. Because the positioning contour is made of an electrically insulating material, for example a plastic, rubber material, a foam or the like, it can be ensured that no unwanted electrical contact occurs, for example between adjacent individual battery cells or the like, via the positioning contour.

According to a very favorable embodiment of the invention, the positioning contour can be designed as a separate component and arranged around the cell housing. Such a configuration can, for example, include a ring with several sections widened in the radial direction, which can be pushed over the cell housing and fixed to it, for example by friction, by gluing, shrinking or the like.

Alternatively, it can also be provided that the positioning contour is designed as part of the module housing. The positioning contour can therefore be a part of the module housing, so that it has corresponding projections which hold the cell housing in the desired position after it has been inserted into the cavity.

It is particularly advantageous, and so it is provided according to an advantageous development of the battery module according to the invention, if the positioning contour interacts in a form-fitting manner with at least one recess in the cell housing. Such a recess can, for example, be a groove within the cell housing, in particular a groove running around the circumference, which can preferably be formed by a bead or a so-called flanged indentation. Both with a positioning contour, which is designed as a separate component, and with an integration of the positioning contour into the module housing, the positioning contour can be locked with this flanging in order to ensure a safe and reliable positioning of the cell housing at least in the height direction. The cell housing can, for example, be pushed into the module housing until the positioning contour integrated in the module housing engages in a form-fitting manner with the corresponding flanging recess of the individual cell housings. If the positioning contour is designed as a separate component, it can be pushed onto the cell housing until it clicks into place, before the cell housing is then introduced into the module housing together with the positioning contour that is already connected to it. The individual battery cell with the positioning contour can hang in the cylindrical cavity and be supported in the direction of gravity above the positioning contour on the module housing. However, this is also possible if the positioning contour is applied to the cell housing without such a positive fit, for example if it is pressed on and/or glued or the like.

The method according to the invention for assembling a battery module in one of the embodiments described above now provides for the individual battery cells to be introduced into the module housing, with them being held in their position by the positioning contour. Subsequently, but not necessarily directly following this, an adhesive is then introduced through the at least one opening between the cell housing and the walls of the cylindrical cavities in the module housing in order to glue the individual battery cells to the module housing. This creates a compact and solid structure for the module, in which a defined gap for the gluing process is set by the positioning contour and maintained during gluing.

A very advantageous embodiment of the method according to the invention further provides that the bonding takes place after electrical contacting of the individual battery cells and/or several Battery modules are carried out. Due to the at least temporary fixation due to the mechanical positioning contour according to the invention, good handling of the battery module is easily possible even if the battery module has not yet been fully manufactured. Therefore, further processing of the battery module can take place in this state, in particular by electrically contacting the individual battery cells and/or several battery modules with one another. The adhesive for bonding the module housing to the cell housings is only introduced afterwards, so that the individual battery cells can still move slightly, possibly during electrical contacting, which is typically done by welding out cell connectors, in order to prevent the cell connectors from moving are under excessive mechanical stress due to the cell casings that have already been permanently fixed by gluing. This could lead to premature failure.

The improved handling with the subsequent gluing can affect both the structure within a module and the combination of several modules, which can first be completely completed and preferably electrically contacted and mechanically positioned relative to one another before their individual battery cells are assembled in the manner described and the modules be glued together. Accordingly, it can be provided for a battery according to the invention that it comprises at least two of the battery modules in the sense described above, which have been glued together.

Further advantageous embodiments of the battery module and the method result from the exemplary embodiments, which are described in more detail below with reference to the figures.

• 1 einen Ausschnitt aus einem Batteriemodul in einer ersten möglichen Ausführungsform gemäß der Erfindung, während der Montage von Batterieeinzelzellen;
• 2 das Batteriemodul gemäß 1 beim Verkleben der Batterieeinzelzellen;
• 3 eine alternative Ausführungsform des Batteriemoduls gemäß der Erfindung;
• 4 eine weitere alternative Ausführungsform eines Batteriemoduls gemäß der Erfindung;
• 5 eine Draufsicht auf ein Batteriemodul gemäß 4 mit einer ersten Ausführungsform einer Positionierungskontur; und
• 6 zwei weitere Möglichkeiten zur Ausgestaltung einer Positionierungskontur an einem Zellgehäuse.

Show:

• 1 a section of a battery module in a first possible embodiment according to the invention, during the assembly of individual battery cells;
• 2 the battery module accordingly 1 when gluing the individual battery cells together;
• 3 an alternative embodiment of the battery module according to the invention;
• 4 a further alternative embodiment of a battery module according to the invention;
• 5 a top view of a battery module according to 4 with a first embodiment of a positioning contour; and
• 6 two further options for designing a positioning contour on a cell housing.

In the representation of the 1 a section of a battery module, designated overall by 1, can be seen in an embodiment according to the invention. The section shown here consists of a module housing 2, which could also be referred to as a module holder or cell holder. This module housing 2 has cylindrical cavities 3 into which individual battery cells 4 are positioned. These individual battery cells 4 are designed as so-called round cells and have a cell housing designated 5, which is typically deep-drawn as a cup-shaped cell housing, for example from an aluminum or steel material. Without this being relevant to the present invention, this usually forms the negative pole of the individual battery cell 4, while electrically isolated from it in the illustration 1 the positive pole protrudes upwards. The cell housing 5 and the individual battery cell 4 are shown in the illustration 1 only labeled accordingly for the individual battery cell 4 shown on the far right, but this applies analogously to the other individual battery cells shown.

The cell housings 5 are designed as cylindrical round housings in accordance with the design of the individual battery cells 4 and have a diameter d, which is smaller than the diameter D of the cylindrical cavities 3 of the module housing 2. The individual battery cells 4 can therefore be mounted in the module housing 2 with a gap 6 remaining between the walls of the module housing 2 and the cell housing 5. In the exemplary embodiment shown here, the individual battery cells 4 or their cell housings 5 have a flanged indentation marked 7 on the individual battery cell 4 shown on the far left, i.e. a type of circumferential groove. This circumferential groove can now form a positive fit with a positioning contour 8, which in the embodiment according to 1 in the module housing 2 or on the walls of the cylindrical cavities 3, interact. As symbolized by the arrow on the individual battery cell 4 shown on the left, it is inserted into the cavity 3 from below. It then locks into the module housing 2, in which the positioning contour 8 interacts in a form-fitting manner with the flanged insert 7 and fixes the individual battery cell 4, as can be seen in the three individual battery cells 4 shown to the right. The enlarged section X in the representation of the 1 shows this interaction between the protruding rib of the positioning contour 8 and the flanging indentation 7 on the cell housing 5 in detail. About these With a form-fitting receptacle, the individual battery cells 4 are fixed or pre-fixed in the module housing 2 in such a way that they are correspondingly fixed both in the height direction marked z and transversely in the transverse direction marked x and the longitudinal direction marked y.

The positioning contour 8 can in particular be integrated into the module housing 2 and consist, for example, of plastic, a rubber material, a foam or similar. Particularly preferably, it can be formed as a one-piece positioning rib directly from the material of the module housing 2. Like the module housing 2, it should also be designed to be electrically insulating.

The battery module 1 with the individual battery cells 4 fixed or pre-fixed in the module housing 2 can now be ideally handled for further production steps without the individual battery cells 4 being moved out of their position. Further production steps such as electrical contacting can now be carried out by welding on cell connectors or the like. After this has been done and all mechanical stresses that can occur with this type of fixation have been leveled out in the battery module 1 through minimal setting movements, further processing can take place. In the representation of the 2 this further processing is shown. The three individual battery cells 4 shown, of which only the leftmost individual battery cell 4 is labeled accordingly, are in the in 1 Described sense fixed and are now glued by an adhesive 10, which is introduced by means of an adhesive nozzle 9. The adhesive 10 is shown in the illustration 2 indicated in irregular hatching. In the enlarged detail Y the 2 it can be seen between the module housing and the cell housing 5.

This positioning contour 8 can also be used as an alternative to the design of the 1 or the 2 be designed as an independent component. This is in 3 indicated. On the far left in the representation of the 3 A single battery cell 4 with a cell housing 5 and the flanged insert 7 can be seen. The positioning contour 8 is designed here as an independent ring, which is applied to the cell housing 5 and locks in a form-fitting manner with the flanged insert 7. This combination of the individual battery cell 4 and positioning contour 8 can then be as shown in the illustration 3 can be seen in the middle in the cylindrical cavities 3 of the module housing 2, so that the individual battery cells 4 are again correspondingly fixed in the height direction z and, due to the design of the positioning contour 8, are also positioned in the transverse direction x and in the longitudinal direction y so that the for the gap 6 provided for later gluing is formed evenly around the circumference of the individual battery cell 4 or its cell housing 5.

Another alternative is in the representation of the 4 to recognize. Here too, the positioning contour 8 is designed as an annular positioning contour 8. The flanged insert 7 in the cell housing 5 of the individual battery cell 4 is omitted here. Rather, the positioning contour 8 is applied to the cell housing 5 in a defined position, for example pressed or shrunk on, glued to the cell housing 5 or the like. The further assembly process is then, as can be seen from the representation of the figure, essentially the same as in the context of 3 described.

In the case of this configuration of the positioning contour 8 as an independent component, it is possible to produce it, for example, from a fixing ring wrapped around the cell housing 5, for example made of rubber, plastic or the like. The positioning contour 8 should preferably consist of an electrically insulating material, especially if the cell housing 5 simultaneously forms one of the poles of the individual battery cell, otherwise the touching positioning contours, as is the case with the embodiment variants 3 and 4 If this is the case, unwanted electrical contact could occur.

In principle, it would also be conceivable to design the positioning contour 8 as a one-piece section of the cell housing 5. For this purpose, for example, an outwardly directed bead that does not run around the entire circumference would be conceivable. Likewise, a flange that does not run all the way around the entire circumference could be used at the upper end of the cup-shaped cell housing 5. The electrical insulation could then be achieved by a (partial) coating of the cell housing 5.

Regardless of whether the positioning contour 8 is designed as an independent component or implemented as part of the module housing 2, it is typically always designed as it appears in the top view 5 is indicated schematically. It consists in the representation of the 5 each consisting of two sections 11 arranged over the circumference of the cell housing 5 or the cylindrical cavity 3, which have a greater extent in the radial direction than the sections 12 in between. All around the circumference are shown in the representation 5 two such sections 11 are arranged, so that two sections 12 of the circumference remain between them, which essentially represent openings 12 in which the volume men or the gap 6 between the cell housing 5 and the walls of the cylindrical cavity 3 remains open. This now offers the opportunity to use the in 2 Already shown adhesive nozzle 9 to introduce the adhesive 10 into the uniform gap 6.

In the representation of the 6 In two possible alternative embodiments, positioning contours 8 are shown around two cell housings 5, which show four of the sections 11 and accordingly four areas in which openings can remain, and three such sections 11. A structure with two to four such sections 11 is typical particularly useful. In principle, more than four such sections 11 would also be conceivable.

In the embodiments described, the positioning contour 8 prevents the individual battery cells 4 from slipping in the cylindrical cavities 3 and thus enables a flexible design of the process chain, in which the individual individual battery cells 4 in the module housing 2 and possibly also several of the module housings 2 together to form an overall battery. which is not shown here, only at the end of the production process in the in 2 shown senses can or must be glued together. Nevertheless, even with a module that is not yet complete, i.e. a battery module 1 with not all of the individual battery cells 4 and/or without the adhesive 10, good handling is already possible without the individual battery cells 4 slipping in their positions. The positioning contours 8 also allow very good tolerance compensation, since they at least determine the position of the individual battery cells 4 in the height direction z, especially in the embodiment according to 4 , in such a way that, regardless of the production tolerances of the cell housing 5 in the height direction, the surfaces of the individual poles can be largely adjusted to the same dimension at least on one of the sides in the height direction z. This particularly facilitates electrical contacting, for example by welding on cell connectors, which has already been mentioned several times. Welding the contact before gluing has the advantage that there is no force effect on the weld seams, which positively counteracts potential damage. In addition, the positioning contours 8 allow a very homogeneous load distribution during handling in the manufacturing process and allow the simple and efficient setting of a defined gap for the adhesive 10, so that, for example, the heat conduction in all directions of the cell housing 5 takes place correspondingly homogeneously due to the adhesive being present everywhere with a uniform thickness can.

Overall, the manufacturing process for such battery modules 1 and the overall batteries constructed from them is simplified and the product quality is improved.

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 3419079 A1 [0002]
• US 2022/0077522 A1 [0003]
• EP 3748714 A1 [0004]

Claims (10)

Battery module (1), comprising a module housing (2) with cylindrical cavities (3) for accommodating individual battery cells (4) with cylindrical cell housings (5), the cylindrical cavities (3) having a larger diameter (D) than the cylindrical cell housings (5 ), and wherein a fixation is provided between the module housing (2) and the respective cell housing (5), which fixes the respective cell housing (5) in a height direction (z) perpendicular to a transverse direction (x) and longitudinal direction (y ) spanning plane fixed relative to the module housing (2), characterized in that the fixation is designed as a mechanical positioning contour (8), which comprises a plurality of sections (11) along a circumference of each cell housing (5), which hold the cell housing (5) relative to the Fix the respective cylindrical cavity (3) of the module housing (2) in such a way that the cell housings (5) are fixed in the transverse direction (x) and in the longitudinal direction (y) in both directions and in the height direction (z) in at least one direction , at least one opening (12) remaining along the circumference, through which a gap 6 between the walls of the cylindrical cavity (3) and the cell housing (5) is accessible. Battery module (1). Claim 1 , characterized in that the positioning contour (8) has a plurality of sections (11) distributed over the circumference with a greater radial extent than the sections in between. Battery module (1). Claim 1 or 2 , characterized in that the positioning contour (8) is made of electrically insulating material. Battery module (1). Claim 1 , 2 or 3 , characterized in that the positioning contour (8) is designed as an independent component and is arranged around the circumference of the cell housing (5). Battery module (1). Claim 1 , 2 or 3 , characterized in that the positioning contour (8) is designed as part of the module housing (2) or as part of the cell housing (5) or is introduced into it. Battery module (1). Claim 4 or 5 , characterized in that the positioning contour (8) interacts in a form-fitting manner with at least one recess (7) in the cell housing (5). Battery module (1). Claim 6 , characterized in that the recess is designed as a flanged indentation (7) in the cell housing (5). Method for assembling a battery module (1) according to one of Claims 1 until 7 , characterized in that the individual battery cells (4) are introduced into the module housing (2), being held in their position by the positioning contour (8), after which, in a subsequent production step, an adhesive (10) is passed through the at least one opening (12). ) is inserted between the cell housing (5) and the walls of the cylindrical cavities (3) in the module housing (2) in order to glue the individual battery cells (4) to the module housing (2). Procedure according to Claim 8 , characterized in that the adhesive (10) is introduced after electrical contacting of the individual battery cells (4) and/or several battery modules (1). Battery with at least two battery modules (1), which are glued together.

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