CN113363647B

CN113363647B - Battery device and motor vehicle with battery device

Info

Publication number: CN113363647B
Application number: CN202110233027.5A
Authority: CN
Inventors: L·克鲁泽
Original assignee: Audi AG
Current assignee: Audi AG
Priority date: 2020-03-05
Filing date: 2021-03-03
Publication date: 2023-05-09
Anticipated expiration: 2041-03-03
Also published as: CN113363647A; DE102020105893A1

Abstract

The invention relates to a battery device (10) comprising a housing (20) and a plurality of battery elements (30) which are arranged next to one another in a receiving space (V) formed by the housing (20), the battery device (10) further comprising at least one separating unit (40) for the battery elements (30), wherein in the receiving space (V) one separating unit (40) is arranged between two adjacent battery elements (30), respectively, wherein the respective separating unit (40) is mounted so as to be movable relative to the housing (20) in a predetermined direction of movement (B) within a predetermined distance range (D).

Description

Battery device and motor vehicle with battery device

Technical Field

The invention relates to a battery device comprising a housing and a plurality of battery elements arranged next to one another in an accommodation space/volume formed by the housing. The battery device further has at least one separating unit for the battery elements, wherein in each case one separating unit is arranged in the receiving space between two adjacent battery elements. The invention also relates to a motor vehicle having a corresponding battery device.

Background

Such a battery device can be designed, for example, as a drive battery for a motor vehicle or an aircraft. The battery device can thus be configured, for example, as a high-voltage battery or as a battery module of a high-voltage battery. "high voltage" in the sense of the present invention means in particular an operating voltage of about 30V to about 1kV at ac voltage or about 60V to about 1.5kV at dc voltage. For supplying electrical energy, i.e. for driving a motor vehicle, the battery arrangement generally has a plurality, i.e. two or more battery elements. Accordingly, the battery element may be configured, for example, as a single battery module comprising a plurality of battery cells or as a single battery cell. In order to form a battery device, the battery elements are arranged in a known manner in a housing and are connected, for example, in series or parallel to one another. As previously described, these battery elements are arranged next to one another, i.e. stacked, in the housing space and thus form a so-called cell stack (Zellstapel).

The separation unit is typically mounted or arranged between the battery elements. Such a separation unit can be configured, for example, as a shear wall, as described in DE 10 2018 204 420 A1. Such a shear wall can be used in particular for structural reinforcement of a battery device or, for example, as a protective wall, for example, as a fire wall.

However, such a separation unit may also be used to reduce or slow the aging speed of the battery element or the battery device. That is, the battery element is generally unstable in shape. That is, each of the battery elements may be deformed due to an internal force that occurs particularly during charging or discharging. Thereby producing a change in the accommodation space of the battery element. This process is also known as "inflation" or "breathing". In order to prevent the battery elements from pressing or moving relative to each other during expansion, the battery elements may be fixed in a housing, for example, and separated from each other by means of the separation unit. However, by fixing between the battery elements or when using rigid and inflexible separation units, clamping or pressing in of the respective battery elements may result, in particular when expanding or sucking in. Thereby, the aging speed of the corresponding battery element is accelerated. In order to extend the service life of the battery device, methods for realizing elastic or flexible separation units between battery elements are known from the prior art.

For example, DE 10 2016 201 604 A1 discloses that between two fixed or rigid separating walls of a battery module, in each case one battery cell is arranged, wherein between a first battery cell and a separating wall adjacent to the first battery cell a first flexibly deformable compensating element is arranged, and between a second battery cell and a separating wall adjacent to the second battery cell a second flexibly deformable compensating element is arranged. The first compensation element and the second compensation element have different deformation constant values.

In this case, however, it is necessary to accurately determine each deformed edge of each balance member in advance so as to be able to slow down the aging process of the battery element or the battery device.

Furthermore, document WO 2017/055161 A1 discloses a battery module having a housing and electrochemical cells, which are arranged side by side in a stacked manner in the housing. The elastic element is arranged between two adjacent individual bodies. These elastic elements provide a predetermined compressive force to each of the battery cells when the cells expand, for example, during a charging or discharging process.

However, uncontrolled movements of the cells or of the separating unit can occur here, for example, in order to compress or compress the individual cells in the housing.

Disclosure of Invention

It is an object of the present invention to provide a battery device that achieves expansion or breathing of individual battery elements while avoiding compression or squeezing of one battery element by the other.

This object is achieved by the subject matter of the independent claims. Advantageous developments of the invention are disclosed in the dependent claims, the following description and the figures.

The invention is based on the recognition that the above object can be achieved by means of a dynamic one-piece auxiliary device, namely a separating unit, which is designed to be movable relative to the housing.

The invention therefore relates to a battery device of the type mentioned, which has a housing and a plurality of battery elements, i.e. two or more battery elements. The battery elements are arranged next to one another or stacked in the receiving space formed by the housing. The battery elements form so-called cell groups in a known manner. Additionally, the battery device has at least one separation unit for the battery elements. In this case, the separating unit is always arranged in the receiving space between two adjacent battery elements. Thus, the battery elements and the separation units are alternately arranged side by side in the case. Thus, the monomer set also comprises a separation unit. In order to achieve expansion without affecting the service life of the battery device or of the individual battery elements, the respective separating unit is supported in such a way that it can move in a predetermined distance range in a predetermined direction of movement relative to the housing. How the distance range and the direction of movement are determined is described in more detail below.

In other words, the separation unit can thus move relative to the housing when the battery element breathes. The displacement or movement is only carried out in the direction of movement and is limited by a predetermined or predefined distance range. Thus, the distance range forms the maximum distance of movement or the maximum distance of movement of the respective separation unit relative to the housing.

The advantage is thereby obtained that the maximum distance between the battery elements is predefined by means of the separation unit, in particular during the contraction or exhalation of the battery elements. However, uncontrolled movements and thus compression of one cell element by the other cell element can be avoided at the same time as the cell element expands or inhales. As a result, forces and tolerances between the battery elements can be compensated for during the service life of the battery device and thus a uniform aging of the battery elements is achieved. Furthermore, the geometric orientation of the battery element in the housing space can also be simplified by means of the separating unit.

The predetermined movement direction is preferably a direction in the stacking direction or the arrangement direction, i.e., parallel to the stacking direction of the battery elements. That is to say that the respective separating unit can be moved with the respective broad side, i.e. with the contact surface facing the respective battery element, towards the respective broad side or contact surface of the respective battery element, or away from the respective battery element. The direction of movement thus preferably describes the movement or movement of the separation unit between two adjacent battery elements. Here, the broad side refers to the face of the geometric shape having the largest surface. In contrast, for example, the respective narrow side is a narrower side of the geometric shape than the wide side. The narrow sides are in particular perpendicular to the respective wide sides, and thus connect two opposite wide sides to each other. The rectangular or cuboid-shaped object has, for example, two opposite broad sides oriented parallel to one another and four narrow sides perpendicular thereto, which connect the two broad sides to one another.

The invention also includes embodiments that yield additional advantages.

Now, an advantageous embodiment of the separating unit for displacing the separating unit relative to the housing is first achieved below.

According to one embodiment, the respective separating unit has at least one guide element on each of the two opposite narrow sides in order to support the respective separating unit in a movable manner relative to the housing. At the same time, the housing also has at least one recess on the respective wall facing the respective narrow side for receiving and guiding the guide element over a predetermined distance along a predetermined direction of movement.

In other words, it is thus possible to insert or insert a respective guide element, preferably into a recess associated with the guide element, which is formed in the wall of the housing. The shape of the recess, in particular the edge of the recess, defines the distance range and the direction of movement. The maximum distance between two adjacent battery elements is therefore also defined by the shape of the recess.

The guide elements may be arranged, for example, as projections or bulges or pins on the respective narrow sides of the separation unit. The recess can be correspondingly embodied as an opening, i.e. a cutout or a groove, in the corresponding wall of the housing.

The two walls comprising the respective recesses are preferably two opposite sides or side walls of the housing. The side surfaces here refer to the walls of the housing, which are oriented perpendicularly to the bottom and/or top surface in the predetermined installation position of the battery device. The bottom and top surfaces are also interconnected by corresponding side surfaces. The installation position is here the position of a battery device for the defined use as an electrical energy store, for example as a drive battery of a motor vehicle. In this case, in the installed position, the bottom and top surfaces are preferably oriented parallel to a predetermined ground surface, for example a roadway ground surface. The narrow side of the separation unit comprising the respective guiding element may thus also be referred to as a lateral narrow side.

In order now to be able to ensure a regular movement of the respective separation unit and to avoid jamming of the separation unit in the housing, according to a further embodiment the respective separation unit preferably has two or more guide elements on each narrow side. That is, the respective separation unit comprises two or more guide elements on two opposite narrow sides, respectively. The guide elements of each narrow side are arranged offset from one another along the respective narrow side perpendicularly to the predetermined direction of movement. Thus, the guide elements have a predetermined distance from each other. Correspondingly, the housing also has two or more recesses on the respective wall surface facing the respective narrow side for receiving and guiding the respective guide element in a predetermined direction of movement over a predetermined distance. The number of recesses per wall preferably corresponds to the number of guide elements. Thus, one recess is assigned to each guide element.

In order to define a predetermined direction of movement, it is proposed according to a further embodiment that the respective guide element is arranged against a first edge and an opposite second edge of the recess perpendicularly to the predetermined direction of movement. The opposite edges of the recess thus define a movement gap of the respective guide element perpendicular to the predetermined movement direction.

In other words, the shape of the respective guide element perpendicular to the predetermined direction of movement matches the shape of the respective associated recess. However, in the direction of the predetermined movement direction, the shape of the recess has a larger dimension than the shape of the corresponding guide element.

In order to ensure or ensure the stability of the housing even when the recess is introduced into the respective wall, it is preferably provided that the guide elements of two adjacent separating units and the respective recess are arranged offset from one another. In other words, the guide elements associated with the respective narrow sides of two adjacent separating units and the corresponding recesses of the respective wall surfaces are arranged offset from one another perpendicular to the predetermined direction of movement.

The recesses of the respective wall surfaces are thus at a predetermined distance from one another in the direction of movement. In this case, each two recesses are formed parallel to the direction of movement, i.e. at one height in the direction of movement, and two adjacent recesses are always formed offset from one another perpendicular to the direction of movement. Similarly, this of course applies to the corresponding guide element. The predetermined distance is preferably specified by the dimensions and expansion characteristics of the respective cell element, i.e. by the expansion of the respective cell element during breathing.

The dimensions of the distance range are advantageously realized in the following embodiments. The distance range is thus 10%, in particular 5%, of the width or thickness of the corresponding battery element. Here, the width or thickness of the battery element in the normal state, that is to say, for example, immediately after the completion of the production, before respiration or expansion occurs. The distance range thus describes how far the guide element can reciprocate in the direction of movement in the recess, i.e. between the two stop edges, i.e. between the above-mentioned first edge and second edge of the recess.

For holding, i.e. for fixing or positioning, the battery element is prevented from slipping out of the receiving space, according to a further embodiment the respective separating unit has at least one holding element/restraining element. Preferably, the holding element is arranged or fastened on the narrow side of the respective separating unit, which connects two opposite or lateral narrow sides comprising the guide element. The narrow side may preferably face the top surface of the housing in the aforementioned mounting position. Thus, the narrow side may also be referred to as the upper narrow side.

The holding element can be embodied in particular as a spring element or a spring clip. Preferably, each holding element holds two adjacent battery elements. That is to say that the holding element extends beyond the upper narrow side in the direction of movement.

In order to ensure the stability of the separation unit, according to a further embodiment, the respective separation unit has an inherently rigid or dimensionally stable frame. The elastic element of the separation unit is held in the frame. Thus, the frame maintains the shape of the elastic element. Thus, the elongation or deformation of the respective elastic element can be brought about by the expansion process when the respective battery element breathes.

The advantage obtained by this embodiment of the separating unit is that the respective separating unit is held stable by the frame on the one hand, but that the respective battery element is provided with additional play for respiration by the elastic element on the other hand.

The respective guide element is preferably formed integrally with the frame. That is, the respective guide element is an integrated part of the frame. Similarly, this preferably applies to the corresponding holding element.

Against this background, it is proposed according to a further embodiment that the frame is configured at least in sections, that is to say partially or completely overlapping the side of the battery element facing the separating unit. In other words, the frame may partially protrude from the respective sides or wide sides of the respective battery elements in a state of being disposed in the case receiving space. Preferably, however, the frame is closed planar to the respective side of the respective battery element.

Therefore, a certain stability between the battery elements can be ensured by the frame.

The invention also relates to a motor vehicle with a battery device as described above. The motor vehicle is preferably designed as a motor vehicle, in particular a passenger car or a truck, or as a passenger car or a motorcycle. In particular, the motor vehicle is configured as an electric vehicle or as a hybrid vehicle. In this case, the battery device can be designed as a drive battery of a motor vehicle.

The invention also includes combinations of features of the described embodiments.

Drawings

Embodiments of the present invention are described below. This is shown:

fig. 1 shows a schematic illustration of an exemplary embodiment of a battery device, wherein a separation unit is arranged as a device aid between battery elements;

fig. 2 shows a schematic diagram of an enlarged view of a battery device; and

fig. 3 shows a schematic diagram of an exemplary embodiment of a separation unit.

Detailed Description

The examples set forth below are preferred embodiments of the present invention. In the examples, the described individual features of the embodiments are each individually characteristic of the invention that can be considered independently of one another, which also individually modify the invention. Thus, the present disclosure also includes combinations different from the combinations shown of the features of the embodiments. Furthermore, the described embodiments may be supplemented by other of the already described features of the invention.

In the drawings, like reference numerals designate functionally identical elements, respectively.

Fig. 1 shows a schematic three-dimensional view of a battery device 10 from a perspective view. The battery device 10 is configured as a battery module. In order to supply electrical energy, the battery device 10 therefore comprises a plurality of battery elements 30 which are arranged side by side in a stacked manner in the accommodation space V formed by the housing 20 of the battery device 10 and are electrically connected to one another in a known manner. The battery elements 30, which are currently constructed as battery cells, thus form a cell stack in a known manner. For a better overview, only two such battery elements 30 are shown in fig. 1 in the housing 20.

Fig. 1 shows the battery device 10 in an installed position as previously described. The housing 20 here comprises four sides or walls 21 which delimit the accommodation space V in the x-direction and in the y-direction. The bottom surface of the housing 20 is formed here by a flange or a projection of two opposite side surfaces 21 of the housing 20. The two opposite side surfaces 21, hereinafter also referred to as side plates 23, are oriented in the x-direction and are therefore arranged parallel to the stacking direction R of the battery elements 30 as a single unit. Thus, the stacking direction corresponds to the x-direction. The other two opposite side faces 21 connecting the side plates 23 to each other are correspondingly oriented perpendicular to the stacking direction R. These sides are also referred to below as closing plates 22. For a better overview, the top surface of the housing 20 is not shown in fig. 1. The bottom surface and the top surface define a receiving space V in the z-direction.

In order to enable the battery elements 30 to breathe or expand in the housing 20 and at the same time avoid a resulting compression or squeezing of the battery elements 30 against each other, a separation unit 40 is provided between two adjacent battery elements 30, respectively. Therefore, the cell group always alternately includes the battery element 30 and the separation unit 40. In this case, each cell element 30 is always oriented with its respective broad side 31 toward the respective broad side 46 of the separating unit 40.

The respective separating unit 40 is supported in the housing 20 so as to be movable in a predetermined distance range D in a predetermined movement direction B relative to the housing 20. That is, when the batteries breathe or expand, the respective separation units 40 may reciprocate relative to the housing in a predetermined movement direction B between two adjacent battery elements 30. The amount by which the respective separation unit 40 can be moved is limited here by the distance range. Thus, the maximum distance between the battery elements 30, which is specified by the separation unit, can be maintained, in particular, when the battery elements 30 contract or exhale. This also has the advantage that the corresponding separating unit 40 also simplifies the geometric arrangement of the battery elements 30 as a single group in the receiving space V. Thus, the separation unit 40 may also be referred to as a monomer aid.

In this case, the movable support of the respective separating unit 40 relative to the housing 20 is achieved by two different measures. The first measure is here the so-called guide elements 42 which are arranged on two opposite narrow sides 41 of the separating unit 40. In order to avoid the jamming of the separating units 40, the respective separating unit 40 currently has two such guide elements 42 on each narrow side 41. The guide elements are arranged at a defined distance from each other along the narrow side 41 in the z-direction, i.e. perpendicular to the direction of movement B. As shown in fig. 1, the narrow sides 41 represent those sides of the respective separation units 40 facing the side plates 23 of the housing 20. Possible dimensions and configurations of these guide elements 42 and separation units are described in detail again later with reference to fig. 2 and 3.

As a second measure, each of the side plates 23 comprises a recess 24 corresponding to the respective guiding element 42. Each guide element is provided with exactly one recess 24. Corresponding guide elements 42 may be guided or inserted through these recesses 24. That is, the respective recess 24 can always receive at least one guide element 42 and guide the same within a predetermined distance range D along a predetermined direction of movement B.

To illustrate this, fig. 2 again shows an enlarged view of the battery device 10 according to fig. 1. As shown in fig. 2 (as well as fig. 3), the guide element 42 is designed as a pin. The guide elements 42 are arranged on the respective narrow side 41 in such a way that they have a greater extension in the direction of movement B than the respective narrow side 41 itself. That is, the guiding elements protrude beyond two opposite broad sides 46 of the separation unit 40 in both directions.

Accordingly, the recess is formed here as a pin-shaped or elongated slot. The dimensions of the recess 24 are adapted to the dimensions of the guide element 42, at least perpendicular to the direction of movement B. That is to say, in order to determine the direction of movement B, the respective guide element is placed against a first edge R1 and a second edge R2 opposite the first edge R1. This makes it possible to achieve a movement of the separating unit 40 in the direction of movement B and at the same time to prevent a movement of the separating unit 40 perpendicular to the direction of movement B, i.e. in the z-direction. In contrast, in the direction of movement B, the dimensions of the recess are greater than the dimensions of the corresponding guide element 42. The distance range D is defined here by the dimensional difference between the respective guide element 41 and the corresponding recess 24 along the movement direction B.

For holding or fixing the battery element 30 in the cell stack arrangement, the respective separation unit 40 further comprises at least one holding element 43. As shown in fig. 1, two such holding elements 43 are provided here. The holding element 43 is arranged on a narrow side 41 of the separation unit 40 facing the top surface of the housing 20. The holding elements 43 are here at a predetermined distance from one another along the narrow side 41, i.e. in the y-direction. Thereby, the battery element 30 can be prevented from slipping out of the accommodation space V perpendicular to the movement direction B, i.e., in the z-direction. Each holding element 43 holds two adjacent battery elements 30. The respective holding element 43 thus likewise projects beyond the two opposite broad sides 46 of the separating unit 40 in the x-direction. According to the embodiment in fig. 1 or 3, the holding elements 43 are embodied here as spring elements which exert a pressing force on the battery element 30 in the z-direction, in particular in the direction toward the bottom.

Fig. 3 finally shows again an exemplary construction of the separation unit. As shown in fig. 3, the separation unit 40 here comprises a frame 44. The frame 44 is designed to be inherently rigid or dimensionally stable. The guide element 42 and the holding element 43 are preferably formed integrally with the frame 44. The elastic element 45 of the separation unit 40 is held by the frame 44. The elastic element 45 is thus clamped in the frame 44. Thus, the stability of the separation unit 40 can be ensured by the frame 44 on the one hand. On the other hand, breathing of the battery element 30 can also be better achieved by the elastic element. The elastic element is therefore unstable in shape and can be reversibly deformed or moved together when the battery element breathes.

Thus, a single body auxiliary device is realized by the separation unit 40 and the recess 24. That is, the battery element 30 or the battery cell may be spatially oriented in the housing 20. Since the cell auxiliary device is dynamic, i.e. can be moved in the distance range D in the predetermined direction of movement B, the forces occurring during expansion can be compensated for during the service life of the battery device 10 and thus a uniform aging of the battery cells or battery elements 30 can be achieved. Furthermore, it is also possible to orient the monomers autonomously along the direction of movement B. In summary, these embodiments show a modular integrated single-body auxiliary device with force and tolerance compensation.

Claims

1. A battery device (10) comprising a housing (20) and a plurality of battery elements (30) arranged next to one another in a receiving space (V) formed by the housing (20), the battery device (10) further comprising at least one separating unit (40) for the battery elements (30), wherein in the receiving space (V) one separating unit (40) is arranged between two adjacent battery elements (30) respectively,

it is characterized in that the method comprises the steps of,

the respective separating unit (40) is mounted so as to be movable relative to the housing (20) in a predetermined direction of movement (B) over a predetermined distance range (D);

in order to support the respective separating unit (40) in a movable manner relative to the housing (20), the respective separating unit (40) has at least one guide element (42) on each of two opposite narrow sides (41), the housing (20) has at least one recess (24) on the respective wall surface (23) facing the respective narrow side (41) for receiving and guiding the guide element (42) along a predetermined movement direction (B) within a predetermined distance range (D); and

each guide element (42) is provided with one of the recesses (24), the respective guide element (42) being guided or inserted through the respective recess (24), and the predetermined distance range (D) being defined by a dimensional difference between the respective guide element (42) and the respective recess (24) along the predetermined direction of movement (B).

2. Battery device (10) according to claim 1, characterized in that, in order to support the respective separating unit (40) in a movable manner relative to the housing (20), the respective separating unit (40) has two or more guide elements (42) on two opposite narrow sides (41), which are arranged offset along the respective narrow side (41) perpendicularly to the predetermined direction of movement (B), the housing (20) has two or more recesses (24) on the respective wall (23) facing the respective narrow side (41) for receiving and guiding the respective guide element (42) along the predetermined direction of movement (B) over a predetermined distance range (D).

3. Battery device (10) according to claim 1 or 2, characterized in that, for defining the predetermined direction of movement (B), the respective guide element (42) is abutted against a first edge (R1) of the recess and a second edge (R2) opposite thereto perpendicularly to the predetermined direction of movement (B).

4. Battery device (10) according to claim 1 or 2, characterized in that the guide elements (42) of two adjacent separating units (40) associated with the respective narrow sides (41) are arranged offset relative to one another perpendicular to the predetermined direction of movement (B) with respect to the recesses (24) of the respective wall surface (23) corresponding to the guide elements.

5. The battery device (10) according to claim 1 or 2, characterized in that the distance range (D) is 10% of the width of the respective battery element (30).

6. The battery device (10) according to claim 1 or 2, characterized in that the distance range (D) is 5% of the width of the respective battery element (30).

7. Battery device (10) according to claim 1 or 2, characterized in that, for holding at least one battery element (30) in the receiving space (V), the respective separating unit (40) has at least one holding element (43).

8. Battery device (10) according to claim 1 or 2, characterized in that the respective separation unit (40) has an inherently rigid frame (44) in which the elastic element (45) of the separation unit (40) is held, wherein the respective guide element (42) is formed integrally with the frame (44).

9. The battery device (10) according to claim 8, characterized in that the frame (44) is partially or completely configured overlapping the side of the respective battery element (30) facing the respective separation unit (40).

10. A motor vehicle having a battery device (10) according to any of the preceding claims 1-9.