DE102022101725A1 - Battery module and method for manufacturing a battery module - Google Patents

Abstract

The present invention relates to a battery module (1) comprising at least one battery cell (2), preferably a prismatic battery cell (2), and at least two pressure plates (3), which are each attached to a first end (5) and a second end (6) of the battery module (1), the at least one battery cell (2) being arranged between the two pressure plates (3) in a stacking direction (4), with at least one clamping strap (9) being provided, which is arranged parallel to the stacking direction (4). , and at least one clamp (10) is provided, which is located on an end face (15) of one of the pressure plates (3) facing away from the at least one battery cell (2) at the first end (5) or at the second end (6) transversely to the stacking direction (4 ) is arranged, with the tightening strap (9) being connected to the clamp (10) and applying a tightening force (14) to the printing plates (3) in the stacking direction (4), or that at least one tightening strap (9) is provided which encloses the pressure plates (3) together with the at least one battery cell (2) in the stacking direction (4) and a first end piece (11) and a second end piece (12) of the clamping strap (9) are connected to one another, the clamping strap (9) is set up to apply a clamping force (14) to the printing plates (3) in the stacking direction (4).

Description

technical field

The present invention relates to a battery module and a method for manufacturing a battery module.

State of the art

Depending on the structure of a vehicle battery or a battery module forming the vehicle battery for accommodating battery cells, measures must be taken to limit expansion of the battery cells in the charging and discharging cycle, so-called swelling. Strapping can be used in a battery module or in a vehicle battery to limit the swelling of (prismatic) battery cells. The battery cells or battery cell stacks are delimited on their outer sides by pressure plates and a prestressing force is applied to the pressure plates by means of the strapping. It is advantageous for the service life of the battery cells if the preload force is neither too high nor too low.

From the DE 10 2018 218 377 A1 a battery module is known in which battery cells are stacked between two end plates in a stacking direction. The end plates are clamped together in the stacking direction by means of a tightening strap, the tightening strap enclosing the two end plates. The stability of the tightening strap is improved by means of an intermediate element, which is attached to the end plate on a side of the respective end plate facing away from the battery cell and provides the tightening strap with a flat, edge-free support side.

From the DE 10 2010 031 641 A1 a pressure plate with variable contact pressure distribution is known. In a battery module, individual battery cells can deform during operation due to charging, discharging or temperature fluctuations. These deformations, which are uneven in the battery cell, especially concentrated in the middle of an outer wall of the battery cell, can be counteracted by means of the pressure plate to extend the service life. A curvature allows the pressure plate to absorb different contact forces and thus counteract the deformations.

From the EP 1 760 806 B1 a battery module is known in which the individual battery cells of the battery module are clamped between two pressure plates by means of a tension belt. For this purpose, the tension belt has a recoverable locking mechanism for connecting the ends of the tension belt. For this purpose, the pressure plates have receiving surfaces for receiving the tension belt and the locking mechanism in a form-fitting manner.

From the EP 2 608 309 A1 a battery module is known whose cells are surrounded by a metal strap to prevent the cells from expanding. For this purpose, the metal clamping band can be closed at both ends by laser welding.

From the U.S. 2018/0151906 A1 a fuel cell module is known, the cells of which are clamped together between two end plates by means of a clamping band. For this purpose, the tightening strap can be wound around the end plates several times and welded at the ends for tightening.

Presentation of the invention

Proceeding from the known prior art, it is an object of the present invention to provide a battery module which is easy to manufacture and which increases the service life of the battery cells, and to provide a corresponding method for manufacturing a battery module.

The task is solved on the one hand by a battery module with the features of claim 1 . Advantageous developments result from the dependent claims, the description and the figures.

Accordingly, a battery module is proposed which comprises at least one battery cell, preferably a prismatic battery cell, and at least two pressure plates, which are each arranged at a first end and a second end of the battery module, the at least one battery cell being arranged between the two pressure plates in a stacking direction.

According to the invention, at least one clamping strap is provided, which is arranged parallel to the stacking direction, and at least one clamp is provided, which is arranged on one of the pressure plates at the first end or at the second end, on an end face of one of the pressure plates that faces away from the at least one battery cell, transversely to the stacking direction, the clamping strap being connected to the clamp and applying a clamping force to the pressure plates in the stacking direction, or at least one clamping strap is provided, which encloses the pressure plates together with the at least one battery cell in the stacking direction and has a first end piece and a second end piece of the clamp bands are connected to each other, wherein the clamping band is adapted to apply a clamping force to the printing plates in the stacking direction.

In other words, the battery module can be provided for a battery in a motor vehicle, the battery cells being spanned by a clamping strap and being pressed together by the clamping force via the pressure plates in such a way that swelling of the battery cells is limited.

For this purpose, a first or a second embodiment of the battery module can be provided. In the first embodiment, at least one bracket may be provided, which is provided on a pressure plate, and the tightening band is connected to the bracket. For example, the respective end piece of the tightening strap can be connected to the clamp on a bracket of the clamp or in the middle of the clamp.

If two clips are provided, a first tightening strap on the upper side of the battery module can be connected parallel to the stacking direction by means of the connecting element to the respective clip on the first and second end of the battery module, in particular to the first clip of the clip, and on the underside of the battery module a second tightening strap can be connected parallel to the stacking direction to the respective clip on the first and second end of the battery module, in particular to a second clip of the clip.

The tightening straps can run parallel to the stacking direction and the clamps can run transversely to the stacking direction. If the stacking direction runs, for example, along a y-axis of a Cartesian coordinate system, transverse to the stacking direction can mean a path along an x-axis and/or a z-axis.

The clamps and the tightening strap can each apply the clamping force that is passed on to the battery cells via the pressure plates, so that the clamping force presses on the battery cells to counteract swelling.

The connecting element can be a laser welded connection, for example. The first variant can therefore preferably include a battery module which is surrounded by two straps and two clamps, which are each arranged on the front side of the pressure plates at the first and second end of the battery module, the strap being connected to the respective clamp at the respective end pieces by means of at least one laser weld point. For example, at least four laser welding points can be used to connect two clamps with two straps to one another for the production of the battery module of the first variant.

A clip is understood here, for example, as a structure that extends across the face of a pressure plate and then forms a section perpendicular thereto that extends on the side of the pressure plate. These sections of the clamp, which extend perpendicularly to the end face of the pressure plate, are also referred to as brackets. The clamp therefore clamps the pressure plate as it were and extends with the bracket in the direction of the respective other pressure plate. The tightening strap can be attached to the two brackets of the clamp.

In the second embodiment of the battery module, in contrast to the first variant, the pressure plates can each be wrapped at least once by at least one tensioning strap without clamps together with the battery cells located in between, the end pieces of the respective tensioning strap being connected to one another by means of the connecting element, so that the tensioning strap encloses the pressure plates and the battery cells and transmits a tensioning force to them, which presses on the battery cells. The connecting element can preferably be a laser welded connection.

This results in the advantage that a clamping force can be applied to the battery cells without external support, so that less installation space is required overall.

One embodiment provides that in the stacking direction between two battery cells and/or between two battery cell stacks and/or between a battery cell and the respective adjacent pressure plate at least one swelling cushion and/or a corrugated sheet metal insert is arranged to compensate for swelling or shrinkage of the respective battery cell(s). In other words, the swellable cushion and/or the corrugated metal insert can equalize or compensate for or limit swelling of the battery cells as a result of charging and discharging processes and/or the service life and/or temperature fluctuations. For example, the swelling cushion can be a swelling pad, for example. For this purpose, the swelling cushion and/or the corrugated sheet metal insert can be designed to be reversibly deformable parallel to the stacking direction and can be softer than the battery cells. The swelling cushion or the corrugated sheet metal insert can therefore be more deformable than the battery cell, ie have a lower modulus of elasticity than that of the battery cell. In particular, the deformability of the swelling cushion transverse to the stacking direction, for example parallel to the x-axis and / o that to the z-axis when the stacking direction is along the y-axis will vary. For example, the swelling cushion can be harder in a center transverse to the stacking direction than at an edge in order to reduce buckling of the battery cells in the center. This can be brought about by selecting a material composition and/or material mixture that is suitable in some areas in the swelling cushion transversely to the stacking direction or by means of a wave pattern when using corrugated sheet metal transversely to the stacking direction. This results in the advantage that swelling of the battery cells in the battery module can be at least partially compensated for, which reduces fluctuations in the clamping force that acts on the battery cells and the clamping strap and/or the clamp. In addition, the clamping force on the battery cell can thereby be set to an operating clamping force value independently of the age and/or an operating state of the battery cell (charged, discharged, warm, cold). Furthermore, this results in the advantage that the tightening strap, the clamp and the connecting element have to absorb a lower clamping force by compensating for the swelling.

One embodiment provides that the pressure plate comprises or consists of a plastic or a metal, in particular aluminum. In other words, the pressure plate may comprise a material stronger than that of a case of the respective battery cells. This results in the advantage that the material of the pressure plates reduces the weight of the battery module and thus of the battery as a whole.

One embodiment provides that the connecting element comprises a material connection (soldered and/or welded and/or adhesive connection), preferably a laser welded connection, or a screwed or riveted connection. The connecting element can also comprise a combination of said mechanical connections. This results in the advantage that a simple and quick mechanical connection can be produced between the tightening strap and the clamp or between the end pieces of the tightening strap, for example by means of laser welding.

One embodiment provides that the tightening strap and/or the clamp are each designed in the form of a strap and comprise or consist of a plastic and/or a metal, in particular high-grade steel. In other words, the pressure plates and the battery cells located between them can be packaged as a tensioning strap by means of the strapping and can thus be subjected to the pretensioning force. This results in the advantage that the battery module and thus the battery requires less space overall and is lighter in weight. Furthermore, this results in the advantage that the strap is stretchable and fluctuations in the mechanical tension as a result of changed environmental conditions can be compensated.

One embodiment provides that the tightening strap and/or the clamp have a tensile strength in the range from 5295 N/mm2 to 7925 N/mm2 (540 kp to 808 kp). Despite the high tensile strength, the swelling can then be compensated for, for example, by means of the swelling cushion and/or corrugated sheet metal insert described above. At the same time, due to the tensile strength, the material thickness of the tensioning strap can be reduced, so that material savings can result.

One embodiment provides that the respective pressure plate at the first and second end of the battery module has a convex shape on the front side transverse to the stacking direction, in particular is curved outwards on the front side. In other words, the pressure plate can have a convex shape transversely to the stacking direction, starting from the battery cell, ie a curved cross section, which is arranged on the end face of the pressure plate facing away from the battery cell. The pressure plate can have a support side facing away from the end face parallel to the stacking direction, which is flat and is set up to press against the battery cell and/or the swelling cushion or the corrugated sheet metal insert. This has the advantage that the tightening strap and/or the clamp resting on the convex, rounded shape of the end face of the respective pressure plate can prevent kinks in the tightening strap and/or the clamp.

One embodiment provides that the tightening strap and/or the clip on the end face of the pressure plate rests in a form-fitting manner transversely to the stacking direction on the end face, preferably in a form-fitting manner with respect to the convex shape of the respective pressure plate. In other words, the tightening strap and/or the clip lie completely on the surface of the end face with their bearing surface, following the convex shape of the end face. For this purpose, the surface of the end face can have a smooth and even structure. This has the advantage that the mechanical stress as a result of the tensioning force applied to the tensioning strap and/or the clamp is distributed more evenly over the tensioning strap and/or the clamp and that the risk of tearing is reduced and the service life of the battery module is increased.

One embodiment provides that the respective pressure plate has a cavity structure. In other words, the pressure plate can have at least one cavity in cross section between the bearing side and the end face. This has the advantage that the weight of the pressure plate is reduced.

The object set above is also achieved by a method for producing a battery module having the features of claim 10 . Advantageous developments of the method result from the dependent claims and the present description and the figures.

1. a. Anordnen der zumindest einen Batteriezelle in einer Stapelrichtung zwischen den Druckplatten an einem ersten und einem zweiten Ende des Batteriemoduls,
2. b. Auflegen zumindest einer Klammer auf einer der Batteriezelle abgewandten Stirnseite der jeweiligen Druckplatte am ersten und zweiten Ende des Batteriemoduls quer zur Stapelrichtung,
3. c. Auflegen zumindest eines Spannbandes jeweils auf einer Oberseite und einer Unterseite des Batteriemoduls parallel zur Stapelrichtung, wobei ein erstes und ein zweites Endstück des jeweiligen Spannbandes jeweils die Klammer am ersten und am zweiten Ende des Batteriemoduls berühren,
4. d. Aufbringen einer Spannkraft auf die zumindest eine Batteriezelle, wobei die Spannkraft von außen auf die Stirnseite der jeweiligen Druckplatte in der Stapelrichtung auf die Batteriezelle drückt,
5. e. Verbinden des ersten und zweiten Endstücks des jeweiligen Spannbandes mit der jeweiligen Klammer am ersten und zweiten Ende des Batteriemoduls mittels eines Verbindungselements,
6. f. Lösen der Spannkraft.

Accordingly, a method for producing a battery module is proposed, which comprises at least two pressure plates, at least one battery cell, at least two straps and at least two clamps. The procedure includes the following steps:

1. a. arranging the at least one battery cell in a stacking direction between the pressure plates at a first and a second end of the battery module,
2. b. Placing at least one clamp on an end face of the respective pressure plate facing away from the battery cell at the first and second end of the battery module transversely to the stacking direction,
3. c. Placing at least one strap on an upper side and an underside of the battery module parallel to the stacking direction, with a first and a second end piece of the respective strap touching the clamp at the first and at the second end of the battery module,
4. i.e. Application of a clamping force to the at least one battery cell, the clamping force pressing from the outside onto the end face of the respective pressure plate in the stacking direction on the battery cell,
5. e. Connecting the first and second end piece of the respective clamping strap to the respective clip at the first and second end of the battery module by means of a connecting element,
6. f. Release of the clamping force.

In other words, at first at least one battery cell is arranged in a stacking direction between the two pressure plates. The battery cells can in particular be prismatic battery cells. At least one clamp can then be placed on the end face of the respective printing plate, with one clamp running in at least one direction transverse to the stacking direction on the end face, for example along an x-axis and/or z-axis of a Cartesian coordinate system if the stacking direction runs along the y-axis. For this purpose, the clamp can each have a clip for connecting to the tightening strap on one side of the clamp, in particular on the top and bottom of the battery module. A first tightening strap can then be arranged on the top and a second tightening strap on the underside parallel to the stacking direction on the at least one battery cell and the pressure plates, so that the first end piece of the respective tightening strap at the first end of the battery module rests against the clamp, in particular against the respective bracket of the clamp on the top or bottom, and the second end piece at the second end against the clamp, in particular on the respective bracket of the clamp on the top or bottom. The respective end piece of the tightening strap on the top can thus be connected to a corresponding bracket of the clamp on the top and the respective end piece of the tightening strap on the underside can be connected to the corresponding bracket of the clamp on the underside.

A clamping force can be applied from the outside to the end faces of the pressure plates parallel to the stacking direction, so that the pressure plates are pressed with the contact side against the at least one battery cell by the clamping force. For example, at least one pressure plate can be used to press against the pressure plate at the first and at the second end, with a shape of the pressure plate being able to correspond to a shape of the end face of the respective pressure plate. If the end face of the pressure plate has a convex shape, for example, the pressure plate can have a form-fitting concave shape. While the tensioning force is being applied, the end pieces of the tensioning strap can be connected to the clamps at the first and second ends by means of the connecting element, with the connecting element preferably being a welded connection, in particular a laser welded connection. The welding can take place while the clamping force is being applied. After welding, the clamping force can then be released from the outside so that the clamping force is applied to the pressure plates by the clamping bands connected to the clamps. The method can be used to produce a battery module, in particular according to the first embodiment, which is subjected to a clamping force by at least two tensioning straps and two clamps, the tensioning straps with the clamps being connected to one another by means of a welded connection, in particular a laser welded connection. This has the advantage that the manufacturing process of a battery module is simplified and in particular accelerated by means of said method, since a Winding process avoided and can be replaced by welding.

The method also includes embodiments that provide additional benefits.

One embodiment provides that the connecting element comprises a material-locking mechanical connection (soldered or welded or adhesive connection), preferably a laser welded connection, or a screwed or riveted connection. In other words, the strap can be connected to the respective bracket by means of laser welding on the face of the pressure plate remote from the battery cell. This results in the advantage that the production step of the connection between the tightening strap and clamp can be carried out quickly on the one hand and on the other hand takes place away from the battery cells, which reduces the error rate in production overall.

One embodiment provides that at least one swelling cushion or corrugated sheet metal insert is inserted between the respective battery cells and/or between the battery cell and the respective pressure plate to compensate for swelling or shrinkage of the respective battery cell. In other words, by compensating for the swelling of the respective battery cell, a mechanical stress fluctuation and thus a peak load acting on the connection between the clamping band and the respective clamp can be reduced. This results in the advantage that the connecting element does not have to be oversized in order to achieve a good service life for the battery module.

One embodiment provides that the clamp encloses the end face of the respective pressure plate in a form-fitting manner. In other words, the clip can rest on the end face transversely to the stacking direction in a form-fitting manner with respect to a cross-sectional shape of the end face of the pressure plate. This results in the advantage that kinks can be avoided and the clip simply has to be placed on the end face and not joined.

One embodiment provides that the clamping force is applied to the respective clamp on the end face of the respective pressure plate and the clamping force deforms the clamp in a form-fitting manner towards the end face, in particular in a form-fitting manner into a convex shape of the respective pressure plate. In other words, while the clamping force is being applied to the end face of the respective pressure plate, the clamp can be deformed by means of the press plate in a form-fitting manner to give the convex shape of the end face of the press plate. This results in the advantage that the clamp does not have to be deformed separately beforehand, which simplifies production.

The battery module is provided for a battery in a motor vehicle, the motor vehicle preferably being designed as a motor vehicle, in particular as a passenger car or truck, or as a passenger bus or motorcycle. The motor vehicle can be electrically driven, in particular a hybrid electric vehicle (HEV, PHEV). An embodiment thus provides a motor vehicle which comprises at least one of said battery module.

The invention also includes implementations that include a combination of the features of several of the described embodiments.

character list

• 1 zeigt einen schematischen Querschnitt der zweiten Ausführungsform des Batteriemoduls,
• 2 zeigt einen schematischen Querschnitt der ersten Ausführungsform des Batteriemoduls; und
• 3 zeigt eine schematische Darstellung eines Verfahrens zur Herstellung der ersten Ausführungsform des Batteriemoduls.

Preferred further embodiments of the invention are explained in more detail by the following description of the figures. show:

• 1 shows a schematic cross section of the second embodiment of the battery module,
• 2 shows a schematic cross section of the first embodiment of the battery module; and
• 3 shows a schematic representation of a method for producing the first embodiment of the battery module.

Detailed description of preferred embodiments

Preferred exemplary embodiments are described below with reference to the figures. Elements that are the same, similar or have the same effect are provided with identical reference symbols in the different figures, and a repeated description of these elements is sometimes dispensed with in order to avoid redundancies. The exemplary embodiments are preferred embodiments of the invention. In the exemplary embodiments, the components described each represent individual features of the invention that are to be considered independently of one another and that further develop the invention independently of one another. Therefore, the disclosure is also intended to encompass combinations of the features of the embodiments other than those illustrated. Furthermore, the described embodiments can also be supplemented by further features of the invention that have already been described.

In 1 is shown schematically a cross section through a battery module 1 according to an embodiment, which example three battery cells 2, which are arranged between two pressure plates 3 at the first end 5 and at the second end 6 of the battery module 1 in the stacking direction 4 and are acted upon by the pressure plates 3 with a clamping force 14 in the stacking direction 4.

The pressure plates 3 have a convex shape 17 with respect to their respective contact side 16 , which faces the battery cells 3 and is set up to press against the respective adjacent battery cell 3 . The pressure plates 3 are curved outwards on their respective end face 15 . In addition, the pressure plates 3 can have a cavity structure 18 with at least one cavity between the end face 15 and the bearing side 16 for weight reduction.

A swelling cushion 7 and/or a corrugated sheet metal insert 8 can be arranged between the battery cells 2 . In addition or as an alternative, a swelling cushion 7 or a corrugated sheet metal insert 8 can be arranged between the respective battery cell 2 and the respective pressure plate 8 .

A clamping band 9 encloses the pressure plates 3 together with the battery cells 2 and additionally the swelling cushion 7 and/or the corrugated sheet metal insert 8 transversely to the stacking direction 4, for example along an x-axis and/or a z-axis if the stacking direction 4 runs along a y-axis. For this purpose, the tensioning strap 9 rests transversely to the stacking direction 4 on an end face 15 of the respective printing plate 3 .

For enclosing, a first 11 end piece and a second end piece 12 of the clamping strap, as shown here for example at the second end 6 of the battery module 1, are connected to one another by means of a connecting element 13.

The clamping band 9 is set up to apply the clamping force 14 parallel to the stacking direction 4 on the end faces 15 of the pressure plates 3 at the first 5 and second end 6 of the battery module 1, so that the pressure plates 3 press with the contact side 16 against the battery cells 2 and additionally or alternatively against the swelling cushion 7 or the corrugated sheet metal insert 8 with the clamping force 14. For this purpose, the connecting element 13 can comprise a detachable mechanical connection, such as a closure or a screw connection, or a non-detachable mechanical connection, such as an adhesive or a welded connection, preferably a laser welded connection, between the first 11 and second end piece 12 of the clamping strap 9. In addition or as an alternative, the first 11 and second end piece 12 of the clamping strap can also be connected to one another at the first end 5 of the battery module 1 by means of the connecting element 13 .

The tightening strap 9 rests in a form-fitting manner on the end face 15 of the pressure plates 3 at the first 5 and/or the second end 6 of the battery module 1, in particular in a form-fitting manner with the convex shape 17 of the pressure plates 3. The convex shape means that the clamping force 14 can be absorbed evenly by the tightening strap 9 and mechanical stress peaks in the tightening strap 9 can thus be avoided, which increases the tear strength of the tightening strap 9 and thus the service life of the battery module 1. The swelling cushion 7 and/or the corrugated metal insert 8 can compensate for swelling or shrinking of the respective battery cell 2 during charging or discharging processes and/or a service life and/or temperature fluctuations, ie swelling. For this purpose, the swelling cushion 7 and/or the corrugated sheet metal insert 8 are reversibly deformable and can be deformed, in particular, with a lower force than the respective adjacent battery cell 2. The swelling cushion 7 and/or the corrugated sheet metal insert 8 can thus at least partially absorb or compensate for a fluctuation in the clamping force 14 as a result of swelling, in particular a swelling or shrinking of the battery cell 2.

The swelling cushion 7 and/or the corrugated sheet insert 8 can, in particular, at least partially absorb the clamping force 14 . For this purpose, the swelling cushion 7 and/or the corrugated sheet metal insert 8 can have at least one deformability, which can preferably be variably configured transversely to the stacking direction 4, for example by means of a corrugated structure of the corrugated sheet metal insert 8 that is variable transversely to the stacking direction or a variable material composition of the swelling cushion 7, so that bulging at certain points of the battery cell 2 as a result of swelling during operation is reduced.

2 shows a further embodiment of the battery module 1, in which, in contrast to the second embodiment, the pressure plates 3 in 1 are each surrounded on their end face 15 by a clip 10 transversely to the stacking direction 4, in particular along an x-axis and/or a z-axis if the stacking direction 4 runs along the y-axis. The tightening strap 9 can thus be attached to the battery cells 2 and the pressure plates 3 parallel to the stacking direction 4, for example on a top 19 and a bottom 20 of the battery module 1, so that the first 11 and second end piece 12 of the tightening strap 9 on the top 19 and on the bottom 20 touch the clamp 10 on the first 5 and second end 6 of the battery module 1. The first end 11 and second end 12 of the respective strap on the top 19 and on the bottom 20 is this with the respective clip 10 at the first end 5 and the second end 6 by means of the conn tion elements 13 connected, in particular each with a bracket of the clamp on the top 19 and the bottom 20, wherein the connecting element 13 is a welded joint, preferably a laser welded joint.

The edges of the clip 10 on the top 20 and bottom 19 can be, for example, brackets, which are welded to the first end piece 11 and second end piece 12 of the tightening strap. So that a clamping force can be applied to the battery cells 2 between the pressure plates 3 by the respective clamping strap 9 on the upper side 19 and the underside 20 and the clip 10 at the first end 5 and second end 6 of the battery module 1, before the first end piece 11 and second end piece 12 of the respective clamping strap 9 are connected, a clamping force 14 is applied from the outside to the front side 15 of at least one pressure plate 3 at the first 5 and/or the second end 6 of the Battery module 1 applied. For example, the clamping force 14 can be applied from the outside along the stacking direction 4 by means of a pressure plate (not shown), which is form-fitting to the end face 15 . For example, the pressure plate can have a concave shape (curved inwards) that is form-fitting to the convex shape 17 (curved outwards) of the pressure plate 3 .

The first end piece 11 and the second end piece 12 of the respective clamping strap 9 on the upper side 19 and the lower side 20 can be connected to the respective clamp 10 at the first end 5 and second end 6 of the battery module 1 by means of the connecting element 13, preferably by means of laser welding, while the clamping force 14 is being applied. After the connection, preferably after the laser welding, the clamping force 14 can be released from the outside, so that the clamping force 14 on the battery cells 2 is maintained via the pressure plates 3 by the respective clamping strap 9 and the respective clamp 10 .

3 FIG. 1 schematically shows a method for producing a battery module 1 according to the first specific embodiment according to the schematic representation 2 , The battery module 1 comprises at least two pressure plates 3, at least one battery cell 2, at least two straps 9 and at least two clamps 10. In a first step S1 at least one battery cell is arranged in a stacking direction 4 between the pressure plates 3 at a first 5 and a second end 6 of the battery module 1 . In a second step S2, at least one clamp 10 is placed on an end face 15 of the respective pressure plate 3 facing away from the battery cell 1 at the first 5 and second end 6 of the battery module 1 transversely to the stacking direction 4, in particular along an x-axis and/or a z-axis if the stacking direction 4 runs along a y-axis. In addition, at least one swelling cushion 7 and/or a corrugated sheet metal insert 8 can be inserted between the respective battery cells 2 and/or between the battery cell 2 and the respective pressure plate 3 to compensate for swelling or shrinkage of the respective battery cell 2 . In a third step S3, at least one strap 9 is placed parallel to the stacking direction 4 on the upper side 19 and the lower side 20 of the battery module 1 . A first end piece 11 and second end piece 12 of the respective clamping strap touch on the top 19 and on the bottom 20 the clamp 10 at the first end 5 and at the second end 6 of the battery module.

In a fourth step S4, a clamping force 14 is applied to the at least one battery cell 2, with the clamping force 14 pressing from the outside on the end face 15 of the respective pressure plate 3 in the stacking direction 4 on the battery cell 2, in particular on the swelling cushion 7 and/or the corrugated sheet metal insert 8. In addition, the clamping force 14 can be applied to the respective clamp 10 on the end face 15 of the respective pressure plate 3 and the clamping force 14 the clamp 1 0 are deformed in a form-fitting manner to the end face 15, in particular in a form-fitting manner to a convex shape 17 (cross-section) of the respective pressure plate 3, so that the respective clamp 10 encloses the end face 15 of the respective pressure plate, in particular the convex shape 17 in a form-fitting manner. For example, the clamping force 14 can be applied by means of a pressure plate that is form-fitting to the convex shape 17 of the pressure plate 3 . The convex shape 17 can prevent kinks on the tightening strap 9 and/or the clamp 10; in particular, this distributes the mechanical stress evenly over the tightening strap 9, so that a mechanical point load or stress peak is avoided, which increases the service life of the battery module 1.

In a fifth step S5, the first end piece 11 and the second end piece 12 of the respective clamping strap 9 are connected to each other with the respective clamp 10 at the first end 5 and second end 6 of the battery module 1 by means of the connecting element 13. For this purpose, the connecting element 13 can comprise an integral mechanical connection, such as a soldered connection, a welded connection or an adhesive connection, preferably a laser welded connection. In addition or as an alternative, the connecting element can comprise a screw connection or a rivet connection.

In a sixth step S6, the clamping force 14 is released, so that the clamping force 14 is now applied to the pressure plates 3 by the respective clamping band and the clamp.

As far as applicable, all the individual features that are presented in the exemplary embodiments can be combined with one another and/or exchanged without departing from the scope of the invention.

Reference List

1

battery module

2

battery cell

3

printing plate

4

stacking direction

5

first end

6

second end

7

swelling pillow

8th

corrugated insert

9

strap

10

bracket

11

first tail

12

second tail

13

fastener

14

resilience

15

face

16

bearing side

17

convex shape

18

cavity structure

19

top

20

bottom

S1

Step 1

S2

step 2

S3

step 3

S4

step 4

S5

step 5

S6

step 6

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited 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.

Patent Literature Cited

• DE 102018218377 A1 [0003]
• DE 102010031641 A1 [0004]
• EP 1760806 B1 [0005]
• EP 2608309 A1 [0006]
• US20180151906A1 [0007]

Claims (15)

Battery module (1) comprising at least one battery cell (2), preferably a prismatic battery cell (2), and at least two pressure plates (3), which are each arranged at a first end (5) and a second end (6) of the battery module (1), the at least one battery cell (2) being arranged between the two pressure plates (3) in a stacking direction (4), characterized, that at least one tensioning strap (9) is provided, which is arranged parallel to the stacking direction (4), and at least one clamp (10) is provided, which is arranged on an end face (15) of one of the pressure plates (3) facing away from the at least one battery cell (2) at the first end (5) or at the second end (6) transversely to the stacking direction (4), the tensioning strap (9) being connected to the clamp (10) and exerting a tensioning force (14) on the pressure plates (3) in the stacking direction (4). brings, or that at least one clamping strap (9) is provided, which encloses the pressure plates (3) together with the at least one battery cell (2) in the stacking direction (4) and a first end piece (11) and a second end piece (12) of the clamping strap (9) are connected to one another, the clamping strap (9) being set up to apply a clamping force (14) to the pressure plates (3) in the stacking direction (4). Battery module (1) after claim 1 , characterized in that in the stacking direction (4) between at least two battery cells (2) and/or between a battery cell (2) and the adjacent pressure plate (3) at least one swelling cushion (7) or a corrugated sheet metal insert (8) is arranged to compensate for swelling or shrinkage of the respective battery cell (2). Battery module (1) according to one of the preceding claims, characterized in that at least two clamps (10) are provided, which are each arranged on the end faces (15) of the pressure plates (3) facing away from the at least one battery cell (2) at the first end (5) and at the second end (6) transversely to the stacking direction (4) and are connected to the clamping strap (9), in particular with a section of the clamping strap (9) arranged on an upper side (19) and a section of the clamping band (9) arranged on an underside (20). straps (9). Battery module (1) according to one of the preceding claims, characterized in that the tightening strap (9) is connected to itself and/or to a clamp (10) by means of a connecting element (13), the connecting element (13) comprising a cohesive (soldered or welded or adhesive connection) mechanical connection, preferably a laser welded connection, or a screwed or riveted connection. Battery module (1) according to one of the preceding claims, characterized in that the tightening strap (9) and/or the clamp (10) are each a strap and comprise or consist of a plastic and/or a metal, in particular a stainless steel. Battery module (1) according to one of the preceding claims, characterized in that the tensioning strap (9) and/or the clamp (10) have a tensile strength in the range from 5295 N/mm2 to 7925 N/mm2 (540 kp to 808 kp). Battery module (1) according to one of the preceding claims, characterized in that the respective pressure plate (3) at the first end (5) and at the second end (6) on the end face (15) transverse to the stacking direction (4) has a convex shape (17), in particular on the end face (15) is curved outwards. Battery module (1) according to one of the preceding claims, characterized in that the tightening strap (9) and/or the clip (10) on the end face (15) of the pressure plate (3) transversely to the stacking direction (4) rest in a form-fitting manner on the end face (15), preferably in a form-fitting manner with respect to the convex shape (17) of the respective pressure plate. Battery module (1) according to one of the preceding claims, characterized in that at least one pressure plate (3) has a cavity structure (18). Motor vehicle comprising at least one battery module (1) according to one of the preceding claims. Method for producing a battery module (1) comprising at least two pressure plates (3), at least one battery cell (2), at least two straps and at least two clamps (10) comprising the steps: a. Arranging the at least one battery cell (2) in a stacking direction (4) between the pressure plates (3) at a first (5) and a second end (6) of the battery module (1), b. Placing at least one clamp (10) on an end face (15) of the respective pressure plate (3) facing away from the battery cell (2) at the first (5) and second end (6) of the battery module (1) transversely to the stacking direction (4), c. Placing at least one strap (9) on an upper side (19) and an underside (20) of the battery module (1) parallel to the stacking direction (4), with a first (11) and a second end piece (12) of the respective tightening strap (9) touches the clip (10) on the first (5) and on the second end (6) of the battery module (1), d. Application of a clamping force (14) to the at least one battery cell (2), the clamping force (14) pressing from the outside onto the end face (15) of the respective pressure plate (3) in the stacking direction (4) on the battery cell (2), e. Connecting the first (11) and second end piece (12) of the respective clamping strap (9) to the respective clamp (10) at the first (5) and second end (6) of the battery module (1) by means of a connecting element (13), f. releasing the clamping force (14). procedure after claim 11 , characterized in that the connecting element (13) comprises a cohesive mechanical connection (soldered or welded or adhesive connection), preferably a laser welded connection, or a screw or rivet connection. Procedure according to one of Claims 11 or 12 , characterized in that between the respective battery cells (2) and/or between the battery cell (2) and the respective pressure plate (3) at least one swelling cushion (7) or a corrugated sheet metal insert (8) is inserted to compensate for swelling or shrinkage of the respective battery cell (2). Procedure according to one of Claims 11 until 13 , characterized in that the clip (10) encloses the end face (15) of the respective pressure plate (3) in a form-fitting manner. Procedure according to one of Claims 11 until 14 , characterized in that the clamping force (14) is applied to the respective clamp (10) on the end face (15) of the respective pressure plate (3) and the clamping force (14) deforms the clamp (10) in a form-fitting manner with respect to the end face (15), in particular in a form-fitting manner into a convex shape (17) of the respective pressure plate.

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