DE102022110664A1 - High-voltage storage for a motor vehicle, motor vehicle with a high-voltage storage and method for producing a high-voltage storage - Google Patents

Abstract

The invention relates to a high-voltage storage device (10) for a motor vehicle (K), with a plurality of battery cells (20), with a housing (30) which protects the plurality of battery cells (20) from environmental influences and at least two battery cells (20 ) has at least partially surrounding housing parts (32, 34), and with connecting elements (50, 52, 54, 56), by means of which the at least two housing parts (32, 34) are joined together at a common joining area (60). The connecting elements (50, 52, 54, 56) are designed as semi-hollow punch rivets. Further aspects of the invention relate to a motor vehicle (K) and a method for producing a high-voltage storage device (10).

Description

The invention relates to a high-voltage storage device for a motor vehicle, with a plurality of battery cells, with a housing which protects the plurality of battery cells from environmental influences and has at least two housing parts that jointly surround the battery cells at least in some areas, and with connecting elements by means of which the at least two housing parts are joined together at a common joining area. Further aspects of the invention relate to a motor vehicle with such a high-voltage storage device and a method for producing a high-voltage storage device.

To connect housing parts, for example upper housing parts and lower housing parts, of a high-voltage storage housing, screw connections are often used, with an electrically conductive ground connection between the housing parts being implemented via cables or ground straps. The screw connections can also be used to fix the cables or ground straps.

It is also known to use rivet connections to connect other components to the housing. That's how it is from the DE 10 2018 214 739 A1 a high-strength cast housing made of an aluminum alloy is known, in which the cast housing can be connected to high-strength steel components via punch rivets. The housing is at least partially covered by a steel plate. The steel plate is held to the housing along its upper edge by the punch rivets.

The object of the present invention is to create a high-voltage storage device of the type mentioned, which is particularly fail-safe and easy to manufacture. It is also an object of the invention to provide a motor vehicle with such a high-voltage storage device and a method for producing such a high-voltage storage device.

This object is achieved by a high-voltage storage device with the features of patent claim 1, by a motor vehicle with the features of patent claim 9, and by a method with the features of patent claim 10. Advantageous embodiments with useful developments of the invention are specified in the subclaims.

A first aspect of the invention relates to a high-voltage storage device for a motor vehicle, with a plurality of battery cells, with a housing which protects the plurality of battery cells from environmental influences and has at least two housing parts that jointly surround the battery cells at least in some areas, and with connecting elements by means of which the at least two housing parts are joined together at a common joining area. The joining area is to be understood as meaning an area where the housing parts are joined together.

According to the invention it is provided that the connecting elements are designed as semi-hollow rivets. This is an advantage because, on the one hand, the use of the semi-hollow punch rivets means that no punching waste is produced, which means that the production of the high-voltage battery can be carried out with particularly little effort due to the elimination of punching waste. The joining area can be limited by a first joining surface of the first housing part and by a second joining surface of the second housing part. The first joining surface and the second joining surface can face each other. In particular, the first joining surface and the second joining surface can be oriented parallel to one another. The first joining surface and the second joining surface can preferably extend at least partially in at least two mutually offset planes. In other words, the respective joining surfaces can have a height offset, for example. As a result, the housing has a particularly high level of rigidity after joining. The connecting elements can be distributed circumferentially along the joining area, i.e. arranged circumferentially.

In an advantageous development of the invention, adjacent connecting elements have a mutual distance between 60mm and 100mm, preferably between 70mm and 90mm and particularly preferably between 75mm and 85mm along the joining area extending on the circumference of the housing. This is advantageous because, on the one hand, a particularly advantageous rigidity of the high-voltage battery or a particularly favorable field line routing can be achieved for this distance. It has been shown that the distance of 100mm is particularly advantageous in terms of favorable field line guidance, whereas the distance of 60mm leads to particularly good stiffness values. A particularly good compromise between rigidity and advantageous field line guidance results from distance values between 75mm and 85mm, such as 80mm. The distance is measured in the circumferential direction of the housing and thus also of the housing parts and can extend along respective or parallel to respective joining surfaces of the respective housing parts that delimit the joining area.

In a further advantageous development of the invention, along the joining area and between An adhesive layer is arranged on the at least two housing parts. This is advantageous because the adhesive layer, together with the connecting elements designed as semi-hollow punch rivets, forms a particularly durable connection between the housing parts. It is particularly advantageous that the adhesive layer achieves a high degree of tightness of the housing, i.e. in particular the penetration of moisture via the joining area into the housing interior of the housing is avoided. This means that additional sealing elements, for example seals surrounding the joining area, can be dispensed with.

In a further advantageous development of the invention, the connecting elements penetrate the adhesive layer. This is advantageous because it means that an adhesive connection that is closed on the circumference is maintained directly around the connecting elements. As a result, the adhesive layer also prevents any penetration of liquid from the environment of the high-voltage battery into any punched holes formed in the housing parts into which the connecting elements are inserted or driven.

The connecting elements can therefore preferably break through the adhesive layer, so that the adhesive layer can be closed around the respective connecting elements, i.e. semi-hollow punch rivets, and can be pressed together by punching as a result of the joining. This gives the adhesive layer a particularly high level of tightness and creates particularly good conditions for the adhesive layer to harden after joining.

In a further advantageous development of the invention, the adhesive layer is formed from a cold-curing adhesive. This advantageously enables the adhesive layer to harden independently, especially after joining, without complex heat treatment.

In a further advantageous development of the invention, a first housing part of the at least two housing parts is designed as an upper housing shell and a second housing part of the at least two housing parts is designed as a lower housing shell. The battery cells can therefore be inserted particularly easily into the lower housing shell and the lower housing shell can then be joined to the upper housing shell.

In a further advantageous development of the invention, the connecting elements are designed as a respective electrical ground connection between the at least two housing parts. A simple ground connection between the housing parts can therefore advantageously be created using the semi-hollow punch rivet. This is due to the fact that, due to production, the semi-hollow punch rivets penetrate into respective housing part walls of the housing parts that delimit the joining area and plastically deform these housing part walls at least in some areas, whereby the housing parts can be connected to one another in a current-conducting manner via the semi-hollow punch rivet.

The high-voltage storage device can in particular be free of additional ground conductors that connect the housing parts to one another in a current-conducting manner. These ground conductors include, for example, ground straps or ground cables. Accordingly, only the connecting elements can be provided as a ground conductor, i.e. as a ground connection between the at least two housing parts. It is particularly advantageous here that the connecting elements take on a multiple function and not only serve to join the housing parts together, but also as electrically conductive elements between the housing parts.

In a further advantageous development of the invention, the at least two housing parts are provided with a corrosion protection layer on the common joining area. This advantageously increases the safety of the high-voltage storage device against failure due to corrosion. In particular, mutually facing joining surfaces of the housing parts can also be provided with the corrosion protection layer. The corrosion protection layer can have a lower electrical conductivity than the respective materials from which the housing parts or the connecting elements are formed. As a result, the corrosion protection layer not only takes on the task of corrosion protection, but also contributes to the electrical insulation of the housing. In particular, the housing parts can be coated with the corrosion protection layer at least on the joining surfaces, preferably also at least partially, particularly preferably on their entire outer surface. A first corrosion protection layer of the first housing part, which delimits the joining area in some areas, can be designed as the first joining surface of the first housing part, and a second corrosion protection layer of the second housing part, which delimits the joining area in certain areas, can be designed as the second joining surface of the second housing part.

Particularly preferably, the at least two housing parts can be free of interruptions in the corrosion protection layer. This means that the at least two housing parts cannot have any areas caused by masking without a corrosion protection layer on the common joining area. In other words, it can be provided that the corrosion protection layer of each of the housing parts is at least unun is broken, with the exception of respective joints at which the respective connecting elements are provided or driven.

A second aspect of the invention relates to a motor vehicle with a high-voltage storage device according to the first aspect of the invention. Such a motor vehicle can be manufactured with little effort.

• - Anordnen der Vielzahl an Batteriezellen zwischen den wenigstens zwei Gehäuseteilen;
• - Fügen der wenigstens zwei Gehäuseteile an dem gemeinsamen Fügebereich anhand der als Halbhohlstanzniete ausgebildeten Verbindungselemente.

A third aspect of the invention relates to a method for producing a high-voltage storage device according to the first aspect of the invention, comprising at least the following steps:

• - Arranging the plurality of battery cells between the at least two housing parts;
• - Joining the at least two housing parts to the common joining area using the connecting elements designed as semi-hollow rivets.

Such a method enables low-cost production of the high-voltage storage device.

When joining, an adhesive layer applied between the at least two housing parts along the joining area can be pressed together. This allows a particularly durable and fluid-tight, in particular waterproof, connection to be created between the housing parts.

After joining, the adhesive layer can be cold cured. In other words, the adhesive layer can be formed from cold-curing adhesive, which hardens following joining. Cold curing is a particularly low-effort curing process in which there is no need to heat the adhesive layer.

The preferred embodiments and their advantages presented in relation to one of the aspects apply accordingly to the other aspects of the invention and vice versa.

The features and combinations of features mentioned above in the description as well as the features and combinations of features mentioned below in the description of the figures and/or shown in the figures alone can be used not only in the combination specified in each case, but also in other combinations or on their own, without the scope of to abandon invention.

Further advantages, features and details of the invention emerge from the claims, the following description of preferred embodiments and the drawings.

• 1a eine Explosionsdarstellung eines Hochvoltspeichers, welcher zumindest zwei Gehäuseteile, nämlich eine Gehäuseoberschale und eine Gehäuseunterschale, sowie zwischen diesen angeordnete Batteriezellen aufweist;
• 1b eine schematische Perspektivansicht des zusammengebauten Hochvoltspeichers, sowie eine stark abstrahierte Darstellung eines Kraftfahrzeugs, welches den Hochvoltspeicher umfasst;
• 2a eine vergrößerte Schnittdarstellung eines Teilbereichs des Hochvoltspeichers in perspektivischer Darstellung, welche einen Fügebereich mit in einem Abstand zueinander angeordneten, als Halbhohlstanzniete ausgebildeten Verbindungselementen des Hochvoltspeichers zeigt, anhand welchen die Gehäuseteile miteinander verbunden sind;
• 2b eine vergrößerte Detailansicht eines in 2a umrandeten Bereichs A, welcher ein einzelnes der als Halbhohlstanzniete ausgestalteten Verbindungselemente zeigt;
• 3a eine schematische Schnittdarstellung entlang einer Schnittebene, welche auch der Schnittansicht in 2a zugrunde liegt und anhand welcher erkennbar ist, dass der Hochvoltspeicher eine entlang des Fügebereichs und zwischen den wenigstens zwei Gehäuseteilen angeordnete Klebstoffschicht aufweist; und
• 3b eine vergrößerte Darstellung eines in 3a gestrichelt umrandeten Bereichs B, welcher eine mittels eines der Verbindungselemente gebildete, zur Verbindung der Gehäuseteile ausgestaltete Stanzverbindung des Hochvoltspeichers zeigt.

The invention is explained again below using a specific exemplary embodiment. This shows:

• 1a an exploded view of a high-voltage storage device, which has at least two housing parts, namely an upper housing shell and a lower housing shell, and battery cells arranged between them;
• 1b a schematic perspective view of the assembled high-voltage storage device, as well as a highly abstracted representation of a motor vehicle which includes the high-voltage storage device;
• 2a an enlarged sectional view of a partial area of the high-voltage storage device in a perspective view, which shows a joining area with connecting elements of the high-voltage storage device which are arranged at a distance from one another and are designed as semi-hollow punch rivets, by means of which the housing parts are connected to one another;
• 2 B an enlarged detailed view of one in 2a outlined area A, which shows a single one of the connecting elements designed as semi-hollow rivets;
• 3a a schematic sectional view along a sectional plane, which is also the sectional view in 2a is the basis and from which it can be seen that the high-voltage storage device has an adhesive layer arranged along the joining area and between the at least two housing parts; and
• 3b an enlarged view of one in 3a Area B outlined by dashed lines, which shows a stamped connection of the high-voltage storage device formed by one of the connecting elements and designed to connect the housing parts.

1a shows an exploded view of a high-voltage storage device 10 for a motor vehicle K, with a large number of battery cells 20, with a housing 30, which protects the large number of battery cells 20 from environmental influences, and at least two housing parts 32, 34 that surround the battery cells 20 together at least in some areas. A first Housing part 32 of the at least two housing parts 32, 34 is designed as an upper housing shell and a second housing part 34 of the at least two housing parts 32, 34 is designed as a lower housing shell. The battery cells 20 are shown in a highly abstracted manner and simplified as a cuboid.

1b shows, in a highly abstracted representation, the motor vehicle K with the high-voltage battery 10. The high-voltage battery 10 serves as a traction battery to supply at least one drive unit machine-trained electrical machine (not shown) of the motor vehicle K.

2a shows in an enlarged view that the connecting elements 50, 52, 54, 56 (of which only four connecting elements are numbered for reasons of clarity) arranged around the circumference of the high-voltage storage device 10, by means of which the at least two housing parts 32, 34 are connected to one another at a common joining area 60 are joined, are designed as respective semi-hollow punch rivets. In an enlarged view, one of the connecting elements 50, 52, 54, 56, namely connecting element 50, is in 2 B shown.

Along the joining area 60 extending on the circumference of the housing 30, the mutually adjacent connecting elements 50, 52, 54, 56 have a mutual distance x between 60mm and 100mm, preferably between 70mm and 90mm and particularly preferably between 75mm and 85mm.

3a shows that an adhesive layer 70 of the high-voltage storage device 10 is arranged along the joining area 60 and between the at least two housing parts 32, 34. 3b shows by way of example that the connecting elements 50, 52, 54, 56 penetrate the adhesive layer 70. To simplify the production of the high-voltage storage device 10, the adhesive layer 70 is formed from a cold-curing adhesive.

In addition, the connecting elements 50, 52, 54, 56 serve as a respective electrical ground connection between the at least two housing parts 32, 34.

The housing parts 32, 34 are also provided with a corrosion protection layer 33, 35 on the common joining area 60. The first housing part 32 is assigned the first corrosion protection layer 33 and the second housing part 34 is assigned the second corrosion protection layer 35. The corrosion protection layers 33, 35 can each be designed as a lacquer layer.

• - Anordnen der Vielzahl an Batteriezellen 20 zwischen den wenigstens zwei Gehäuseteilen 32, 34;
• - Fügen der wenigstens zwei Gehäuseteile 32, 34 an dem gemeinsamen Fügebereich 60 anhand der als Halbhohlstanzniete ausgebildeten Verbindungselemente 50, 52, 54, 56.

In a method for producing the high-voltage storage device 10, the following steps can be carried out:

• - Arranging the plurality of battery cells 20 between the at least two housing parts 32, 34;
• - Joining the at least two housing parts 32, 34 to the common joining area 60 using the connecting elements 50, 52, 54, 56 designed as semi-hollow rivets.

When joining, an adhesive layer 70 applied between the at least two housing parts 32, 34 along the joining area 60 can generally be pressed together. This allows a particularly durable and fluid-tight, in particular waterproof, connection to be created between the housing parts 32, 34.

Cold curing of the adhesive layer 70 can then generally take place. In other words, the adhesive layer 70 can be formed from cold-curing adhesive, which hardens following joining. Cold curing represents a particularly low-effort curing process in which heating of the adhesive layer 70 can be dispensed with.

Through a combination of an adhesive layer with the connecting elements 50, 52, 54, 56 designed as semi-hollow punch rivets for connecting the housing parts 32, 34, all functions (tightness, mechanical connection, ground connection, EMC protection) are fulfilled at the same time. In particular, by connecting the first housing part 32 to the second housing part 34 by attaching the connecting elements 50 (semi-hollow punch rivets) on the circumference, with two adjacent connecting elements 50 having the distance x with a value of approximately 80mm (between 75mm and 85mm). EMC (electromagnetic compatibility) can be ensured in a particularly advantageous manner, especially since the connecting elements 50 are electrically conductive. Ensuring EMC is achieved without additional measures, such as without additional shielding films inside or outside the housing 30. In addition, this allows for optimized utilization of installation space and a simplified assembly process. The use of cold-curing adhesive for the adhesive layer 70 in conjunction with the connecting elements 50, 52, 54, 56 designed as semi-hollow rivets leads to a very good sealing effect, especially if the distance x between the connecting elements 50, 52, 54, 56 is preferably 80 mm. This results in a particularly small gap between the housing parts 32, 34 at the joining area 60, with the adhesive layer 70 hardly being applied. After joining, the adhesive layer 70 can preferably have a height of less than or equal to 0.2 mm, which means that a particularly good sealing effect can be achieved while at the same time requiring little space for the adhesive layer 70.

Reference symbol list

10

High-voltage storage

20

Battery cells

30

Housing

32

first housing part

33

first corrosion protection layer ()

34

second housing part

36

second corrosion protection layer

50

connecting element

52

connecting element

54

connecting element

56

connecting element

60

joining area

70

adhesive layer

K

motor vehicle

x

Distance

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

• DE 102018214739 A1 [0003]

Claims (10)

High-voltage storage (10) for a motor vehicle (K), with a plurality of battery cells (20), with a housing (30) which protects the plurality of battery cells (20) from environmental influences and at least two battery cells (20) together, at least in some areas has surrounding housing parts (32, 34), and with connecting elements (50, 52, 54, 56), by means of which the at least two housing parts (32, 34) are joined together at a common joining area (60), characterized in that the connecting elements (50, 52, 54, 56) are designed as semi-hollow punch rivets. High-voltage storage (10). Claim 1 , characterized in that along the joining area (60) extending on the circumference of the housing (30), connecting elements (50, 52, 54, 56) adjacent to one another have a mutual distance (x) between 60mm and 100mm, preferably between 70mm and 90mm and particularly preferably between 75mm and 85mm. High-voltage storage (10). Claim 1 or 2 , characterized in that an adhesive layer (70) is arranged along the joining area (60) and between the at least two housing parts (32, 34). High-voltage storage (10). Claim 3 , characterized in that the connecting elements (50, 52, 54, 56) penetrate the adhesive layer (70). High-voltage storage (10) according to one of the Claims 3 or 4 , characterized in that the adhesive layer (70) is formed from a cold-curing adhesive. High-voltage storage (10) according to one of the preceding claims, characterized in that a first housing part (32) of the at least two housing parts (32, 34) is designed as an upper housing shell and a second housing part (34) of the at least two housing parts (32, 34) is designed as a lower housing shell is. High-voltage storage (10) according to one of the preceding claims, characterized in that the connecting elements (50, 52, 54, 56) are designed as a respective electrical ground connection between the at least two housing parts (32, 34). High-voltage storage (10) according to one of the preceding claims, characterized in that the at least two housing parts (32, 34) are provided with a corrosion protection layer (33, 35) on the common joining area (60). Motor vehicle (K) with a high-voltage battery (10) according to one of Claims 1 until 8th . Method for producing a high-voltage storage device (10) according to one of the Claims 1 until 8th , comprising at least the following steps: - arranging the plurality of battery cells (20) between the at least two housing parts (32, 34); - Joining the at least two housing parts (32, 34) to the common joining area (60) using the connecting elements (50, 52, 54, 56) designed as semi-hollow rivets.

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