DE102022004514A1 - Energy storage device for a battery module of an at least partially electrically operated motor vehicle - Google Patents

Abstract

The invention relates to an energy storage device (10) for a battery module of an at least partially electrically operated motor vehicle, in which a plurality of solid cells (16) are arranged in an interior (14) of the energy storage device (10), wherein respective electrodes (18, 20) of the solid cells (16) are each contacted with one another, so that at least a first pole (22) and a second pole (24) are formed on the energy storage device (10), wherein the solid cells (16) are designed to be movable within the interior (14) and at least partially the respective electrodes (18, 20) are designed as sliding contacts, wherein the sliding contacts contact at least a first current busbar (26) of the energy storage device (10), and wherein at least the first current busbar (26) is contacted with the first pole (22).

Description

The invention relates to an energy storage device for a battery module of an at least partially electrically operated motor vehicle according to the preamble of patent claim 1.

So-called solid cells are already known from the prior art, which move due to a so-called swelling, both relative to each other and relative to the corresponding poles of a housing of the energy storage device. Furthermore, during assembly, the stack of solid battery cells is preferably introduced, in particular in order to reduce the housing complexity, whereby a relative movement occurs.

The WO 2021/020 237 A1 discloses a secondary battery, wherein a positive electrode has a coated portion coated with a positive electrode active material layer and a positive electrode active material-uncoated portion, both of which are provided on a tape-shaped positive electrode foil, a negative electrode has a coated portion coated with a negative electrode active material layer and also has a negative electrode active material-uncoated portion, both of which are provided on a tape-shaped negative electrode foil, wherein the positive electrode active material-uncoated portion is connected to a positive electrode current collector at one end of an electrode winding, wherein the negative electrode active material-uncoated portion is connected to a negative electrode current collector at the other end of the electrode winding, wherein the positive electrode active material-uncoated portion and/or the negative electrode active material-uncoated portion have surfaces formed by overlapping by bending in the direction of the central axis of the wound structure, and wherein observation of the cross sections of the uncoated active material portions along a plane containing the central axis shows that at least Sections of the sections with uncoated active material near the central axis are bent in several folds.

The EN 10 2018 132 147 A1 describes a method of forming a bus bar including, among other things, folding a sheet of material to form a plurality of folds that divide the sheet into a plurality of segments. The method further includes identifying a desired size for a terminal receiving recess in the bus bar. In response to the desired size, the method folds at least some of the segments relative to each other to provide at least some of the folds according to a first process or a different, second process. An example battery assembly includes, among other things, a bus bar formed from a sheet of material. The bus bar has a terminal receiving recess. Folds are formed within the sheet that divide at least a portion of the sheet into a plurality of segments. Some segments are folded relative to each other and at least some of the folds to provide the terminal receiving recess in the bus bar.

The object of the present invention is to provide an energy storage device by means of which an improved operation of the energy storage device can be realized.

This object is achieved by an energy storage device according to the independent patent claim. Advantageous embodiments are specified in the subclaims.

One aspect of the invention relates to an energy storage device for a battery module of an at least partially electrically operated motor vehicle, in which a plurality of solid cells are arranged in an interior of the energy storage device, wherein respective electrodes of the solid cells are each contacted with one another, so that at least one first pole and one second pole are formed on the energy storage device.

It is provided that the solid cells are designed to be movable within the interior and at least partially the respective electrodes are designed as sliding contacts, wherein the sliding contacts contact at least a first current busbar of the energy storage device, and wherein at least the first current busbar is contacted with the first pole.

In particular, it is therefore intended that the respective solid-state cells have a small or extended overhang of the conductive electrode layers. These rub on the conductive connection to the cell pole, which enables the movable electrical contact. The conductive connection is in particular the current busbar.

This has the particular advantage that no further connection technology is required, which eliminates an additional work step and the accessibility of the tool. Furthermore, there is no mechanically fixed connection to connect the cell poles, so that relative movement is possible.

It can be provided that, for example, a respective solid-state cell has a first electrode and a second electrode. These can be designed, for example, as a positive pole or as a negative pole. The current busbar is designed in such a way that it electrically contacts both a positive pole and a negative pole, depending on the embodiment, for example a series connection or a parallel connection of the electrodes is provided. The respective current busbar is then in turn connected to a pole and can then in turn serve as a current collector for the battery module.

In particular, it is provided that a solid cell stack is formed within the interior with a large number of solid cells. The solid cells can be connected in parallel or in series. The electrodes are formed on the respective sides of the solid cells and are now designed as sliding contacts. At least one current collecting rail can then be formed on the respective sides.

According to an advantageous embodiment, the energy storage device has a second current busbar and the other electrodes are also designed as sliding contacts and are in contact with the second current busbar, the second current busbar being in contact with the second pole. For example, a first electrode of the solid-state cell can be in contact with the first current busbar and a second electrode of the solid-state cell can be in contact with the second current busbar. This makes it possible for current busbars to be formed on both sides of the energy storage device, for example, so that reliable movement, in particular based on cell swelling of the solid-state cells, can be compensated.

A further advantageous embodiment provides that the other electrodes are in contact with a metal housing of the energy storage device and the second pole is in contact with the metal housing. In particular, the first current busbar is only formed on one side of the energy storage housing. The second pole is then in turn in contact with the metal housing, with the respective electrodes also in contact with this. Only one current busbar is therefore necessary. In other words, it can be provided that the first electrode of a first solid-state cell is in contact with the first current busbar and the second electrode is in contact with the metal housing.

It is also advantageous if the energy storage device additionally has a guide device for guiding the solid cells during a movement. This makes it possible to ensure that only predetermined movements of the battery cells are carried out during a corresponding swelling. In particular, the guide device is designed in such a way that it only extends along a longitudinal direction or vertical direction of the energy storage device and thus only allows movement in this one direction.

Furthermore, it has proven to be advantageous if the guide device is designed as a second busbar and is in contact with the housing and the second pole. In particular, the guide device can thus fulfill a dual task, namely, on the one hand, guiding the battery cells or solid cells and simultaneously forming the busbar. This means that the energy storage device can be provided with a reduced number of components.

A further advantageous embodiment provides that the respective solid cells have guide recesses on a side of the solid cells facing the guide device, which correspond to the guide device. These can be conical, for example, whereby a reliable arrangement of the solid cells on the housing can be realized and at the same time reliable guidance can be provided.

It is also advantageous if a housing of the energy storage device is designed to be electrically insulated from the solid-state cells. In particular, the energy storage device then has at least two busbars. In particular, an insulating layer can be formed between the busbars and the housing itself. This makes it possible for a person to touch the housing.

Furthermore, it has proven to be advantageous if the respective poles are formed on an upper side of a housing of the energy storage device. This means that, for example, a cell connector can be reliably arranged on the upper side or on the poles.

A further advantageous embodiment provides that the respective poles are formed on respective side parts of a housing of the energy storage device. In particular, these are formed opposite one another, in particular on the respective sides when viewed from above. An alternative embodiment can thus be form of power which, depending on the design, can reliably provide electrical energy.

It has also proven to be advantageous if the respective electrodes to be connected have an excess length, so that they are layered at least in some areas and contact at least the first busbar. Layered is to be understood in particular as meaning that at least two electrodes of neighboring solid-state cells overlap in some areas. In particular, it can be provided that the electrodes, which are designed as thin foils, are pressed vertically onto the busbar, for example, which in turn has elevations to ensure that contact is made with all foils with different lengths due to tolerances. Alternatively or additionally, thin foils can be bent by placing them vertically or moving them together transversely. There are also elevations on the busbar to compensate for tolerances. Furthermore, the lengths should be designed in such a way that surrounding foils preferably touch one another and thus form a redundant current path. A particular advantage is that the contact of the individual busbars is defined by the elevations and thus tolerances between the foils are compensated for.

Furthermore, the invention also relates to a battery module with at least one energy storage device according to the preceding aspect. A further aspect of the invention therefore also relates to a motor vehicle with at least one battery module according to the preceding aspect. The motor vehicle can be at least partially electric or fully electric.

Advantageous embodiments of the energy storage device are to be regarded as advantageous embodiments of the battery module and of the motor vehicle.

Further advantages, features and details of the invention emerge from the following description of preferred embodiments and from the drawings. 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 alone in the figures can be used not only in the combination specified in each case, but also in other combinations or on their own, without departing from the scope of the invention.

• 1 eine schematische Schnittansicht einer Ausführungsform einer Energiespeichervorrichtung;
• 2 einen vergrößerten Abschnitt der 1;
• 3 weitere schematische Ansicht einer Ausführungsform einer Energiespeichervorrichtung;
• 4 eine weitere schematische Seitenansicht gemäß einer Ausführungsform einer Energiespeichervorrichtung;
• 5 eine schematische Seitenansicht der Energiespeichervorrichtung nach 4;
• 6 eine weitere schematische Seitenansicht einer Ausführungsform der Energiespeichervorrichtung; und
• 7 eine weitere schematische Seitenansicht einer Ausführungsform der Energiespeichervorrichtung

Showing:

• 1 a schematic sectional view of an embodiment of an energy storage device;
• 2 an enlarged section of the 1 ;
• 3 further schematic view of an embodiment of an energy storage device;
• 4 a further schematic side view according to an embodiment of an energy storage device;
• 5 a schematic side view of the energy storage device according to 4 ;
• 6 a further schematic side view of an embodiment of the energy storage device; and
• 7 a further schematic side view of an embodiment of the energy storage device

1 shows a schematic sectional view of an embodiment of an energy storage device 10. In the present embodiment, the energy storage device 10 has a housing 12. The housing 12 in particular forms an interior space 14, wherein a plurality of solid cells 16 are located in the interior space 14. The solid cells 16 have respective electrodes 18, 20. The energy storage device 10 also has a first electrical pole 22 and a second electrical pole 24. For example, the first electrical pole 22 can be designed as a positive pole and the second electrical pole 24 as a negative pole.

In particular, it is provided that the solid cells 16 perform a movement 40 based on a swelling of the solid cells 16 when there is a change in the state of charge or age. In order to compensate for this movement 40, it is provided that they are designed to be movable in the interior 14. For this purpose, in the present embodiment, it is particularly provided that a first current busbar 26 and a second current busbar 28 are provided on a respective left and right side. The electrodes 18, 20 are designed as sliding contacts and contact the current busbars 26, 28. In the present embodiment, it is particularly provided that first electrodes 18 contact the first current busbar 26 and second electrodes 20 contact the second current busbar 28. The current busbars 26, 28 are in turn contacted with the respective poles 22, 24. In particular, the first current busbar 26 is contacted with the first pole 22 and the second current busbar 28 is contacted with the second pole 24. Furthermore, in the present embodiment It is provided that the housing 12 is electrically insulated from the busbar and for this purpose has, for example, an insulating layer 30.

2 shows a schematic enlarged view of the 1 . In particular, in the present embodiment, two solid cells 16 are shown as well as first electrodes 18. For example, it is shown here that the electrodes 18 have an excess length, so that a corresponding contact with the first busbar 26 is ensured.

3 shows a further schematic view of an embodiment according to an energy storage device 10. Here it is shown that the poles 22, 24 can be formed on respective side regions 32, while in the 1 the poles 22, 24 are formed on an upper side 42.

4 shows a further schematic side view according to an embodiment of an energy storage device 10. In the present exemplary embodiment, it is shown in particular that only a first busbar 26 is formed. The first electrodes 18 are contacted with the first busbar 26. The first busbar 26 is in turn contacted with the first pole 22. In this exemplary embodiment, the housing 12 is in particular designed to be electrically conductive and the second electrodes 18 electrically contact the housing 12 and are thus contacted with the second pole 24. In particular, the housing 12 is thus designed to be electrically conductive and contacts the second pole 24. The insulation layer 30 is in turn formed between the first busbar 26 and the housing 12 so that electrical insulation can be carried out.

5 shows a schematic side view of the 4 , in particular on a side area 32. In particular, it is shown that the energy storage device 10 can additionally have a guide device 34 for guiding the solid cells 16. The guide device 34 can also be designed, for example, as a second busbar 28 and can be electrically contacted with the housing 12 and the second pole 24. Furthermore, the 5 that the respective solid cells 16 have guide recesses 36 on a side of the solid cells 16 facing the guide device 34, which correspond to the guide device 34.

6 shows a further schematic side view of an embodiment of the energy storage device 10. In the present embodiment, it is shown in particular that the busbars 26, 28 can also be arranged elsewhere, in particular now in a front of the housing 12 opposite the 1 , can be arranged. The electrodes are therefore not located at the respective ends of the solid cells 16, but rather located at the front.

7 shows a further schematic side view of an embodiment of an energy storage device 10. In the present exemplary embodiment, it is shown in particular that the electrodes 18, 20, in this case in particular the first electrodes 18, have an excess length, so that they contact at least the first busbar 26 in a layered manner at least in some areas. In particular, they are designed to overlap in an overlap region 38.

List of reference symbols

10

Energy storage device

12

Housing

14

inner space

16

Solid state cell

18

first electrode

20

second electrode

22

first pole

24

second pole

26

first busbar

28

second busbar

30

Insulation layer

32

Page area

34

Guide device

36

Guide bulge

38

Overlap area

40

Movement

42

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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 accepts no liability for any errors or omissions.

Cited patent literature

• WO 2021020237 A1 [0003]
• DE 102018132147 A1 [0004]

Claims (10)

Energy storage device (10) for a battery module of an at least partially electrically operated motor vehicle, in which a plurality of solid cells (16) are arranged in an interior (14) of the energy storage device (10), wherein respective electrodes (18, 20) of the solid cells (16) are each contacted with one another, so that at least a first pole (22) and a second pole (24) are formed on the energy storage device (10), characterized in that the solid cells (16) are designed to be movable within the interior (14) and at least partially the respective electrodes (18, 20) are designed as sliding contacts, wherein the sliding contacts contact at least a first current busbar (26) of the energy storage device (10), and wherein at least the first current busbar (26) is contacted with the first pole (22). Energy storage device (10) according to Claim 1 , characterized in that the energy storage device (10) has a second current collecting bar (28) and the other of the electrodes (18, 20) are designed as sliding contacts and are contacted with the second current collecting bar (28), wherein the second current collecting bar (28) is contacted with the second pole (24). Energy storage device (10) according to Claim 1 , characterized in that the respective other electrodes (18, 20) are contacted with a metallic housing (12) of the energy storage device (10) and the second pole (24) is contacted with the metallic housing (12). Energy storage device (10) according to one of the preceding claims, characterized in that the energy storage device (10) additionally has a guide device (34) for guiding the solid cells (16) during a movement (40). Energy storage device (10) according to Claim 3 and 4 , characterized in that the guide device (34) is designed as a second current collecting rail (28) and is contacted with the housing (12) and the second pole (24). Energy storage device (10) according to Claim 4 and/or 5, characterized in that the respective solid cells (16) have guide recesses (36) on a side of the solid cells (16) facing the guide device (34), which guide recesses correspond to the guide device (34). Energy storage device (10) according to Claim 1 or 2 or 4 , characterized in that a housing (12) of the energy storage device (10) is electrically insulated from the solid cells (16). Energy storage device (10) according to one of the preceding claims, characterized in that the respective poles (22, 24) are formed on an upper side (42) of a housing (12) of the energy storage device (10). Energy storage device (10) according to one of the Claims 1 until 8th , characterized in that the respective poles (22, 24) are formed on respective side parts (32) of a housing (12) of the energy storage device (10). Energy storage device (10) according to one of the preceding claims, characterized in that the respective electrodes (18, 20) to be connected have an excess length, so that they contact at least the first current collecting bar (26) in a layered manner at least in some regions.

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