CN115764133A

CN115764133A - Battery device

Info

Publication number: CN115764133A
Application number: CN202211072001.8A
Authority: CN
Inventors: 英戈·豪斯勒; 迪克·霍夫曼; 鲁迪格·克瑙斯
Original assignee: Mahle International GmbH
Current assignee: Mahle International GmbH
Priority date: 2021-09-03
Filing date: 2022-09-02
Publication date: 2023-03-07
Also published as: DE102021209742A1

Abstract

The invention relates to a battery device for a battery electric vehicle, comprising a plurality of battery modules, each of which has a plurality of battery cells. Each battery module has a module positive electrode and a module negative electrode. The battery modules form a series circuit in which every two battery modules following one another are electrically connected to one another by means of an electrical connector which electrically connects the module positive pole of one battery module to the module negative pole of the other battery module. The following structure will be cost effective: the battery modules are configured in a rectangular shape such that a module positive electrode and a module negative electrode are located in diagonally opposite regions of the respective battery modules, and the battery modules form a first battery module type and a second battery module type, which are different from each other in that: the module anode and the module cathode are arranged in a mirror image reversal mode.

Description

Battery device

Technical Field

The present invention relates to a battery device for a battery electric vehicle.

Background

Battery electric vehicles are equipped with a traction battery that provides electrical energy to power the electric drive of the vehicle. The invention relates to a battery device which can form such a traction battery or a part of such a traction battery.

Such battery arrangements usually have a plurality of battery modules, which in turn each have a plurality of battery cells, which are actually arranged next to one another or stacked on one another in the longitudinal direction of the module. The battery unit forms a rechargeable battery (i.e., a secondary battery), which can also be referred to as a secondary battery. The battery cells are electrically connected to each other in each battery module such that each battery module has exactly one module positive electrode and exactly one module negative electrode. Furthermore, the battery modules are arranged side by side and connected in series within the battery device such that they form a series circuit. Such a series circuit of battery modules has exactly one device positive pole and exactly one device negative pole at the battery device. The battery device may be electrically integrated into a battery system (e.g., of a vehicle) via the device positive electrode and the device negative electrode. In particular, electrical power can be tapped or supplied there. In the series circuit, every two battery modules following one another are electrically connected to one another by means of an electrical connector. Each connector electrically connects the module positive electrode of one battery module to the module negative electrode of the other battery module. These connectors can be designed as cables, rods, rails, etc. A connector designed as a conductor rail is preferably used. Since these connectors have to conduct high currents, the connectors are relatively robust or are equipped with a large current-carrying cross section. In addition, the connectors typically use relatively expensive materials (i.e., such as copper) characterized by low electrical resistance. As a result, these connectors are relatively expensive.

In the field of mass production, and in particular in mass production, the principle of identical components has been established to avoid the cost of forming variants. Accordingly, the battery modules within a battery device are typically identical components. Thus, in the battery device, the module cathodes and the module cathodes, which have to be connected to one another for the series circuit, are relatively far apart from one another, whereby correspondingly long connectors are required. For example, the connector length can be greater than the module width measured transverse to the module longitudinal direction. Long connectors are relatively expensive due to the large amount of material used.

Disclosure of Invention

The present invention addresses the following problems: an improved embodiment is proposed for a battery device of the type mentioned above, which is characterized in particular in that it can be realized with reduced manufacturing costs.

According to the invention, this problem is solved by the subject matter of the independent claims. Advantageous embodiments are the subject of the dependent claims.

The invention is based on the following general idea: two different types of battery modules are used in a battery device, and these battery modules are configured so that they can be disposed in the battery device such that a module positive electrode and a module negative electrode to be electrically connected to each other by means of a connector are relatively close to each other. As a result, the connectors required for the electrical connection of the battery module can be designed relatively short, thereby significantly reducing the material expenditure required for the respective connectors. The fact shows that: the additional cost of the two different battery module types is significantly lower than the savings that can be achieved with significantly shorter connectors. Overall, the battery device proposed here can therefore be manufactured relatively inexpensively, even in large quantities.

In detail, the present invention proposes: the battery module is essentially designed as a cuboid, so that the battery module is designed as a rectangle in a module cross section running parallel to the module longitudinal direction. Furthermore, the battery cells in each battery module are electrically connected to one another such that each module positive electrode and each module negative electrode are located in diagonally opposite regions of each battery module in the module cross section. Further, the battery modules of the battery device form a first battery module type and a second battery module type, which are different from each other in that: the module positive electrode and the module negative electrode are mirror-inverted in the first battery module type compared to the second battery module type. The mirror plane here extends either perpendicularly to the module longitudinal direction or perpendicularly to the module cross section and parallel to the module longitudinal direction. For example, each battery module has four corner regions in its rectangular module cross section, which follow one another in the circumferential direction and form a first to a fourth corner region. As described above, in each battery module, the module positive electrode and the module negative electrode are located in diagonally opposite regions, i.e., in the first corner region and the third corner region or in the second corner region and the fourth corner region, for example. For example, at this time, it is possible to set: in the battery module of the first battery module type, the module positive electrode is located in the fourth corner region, and the module negative electrode is located in the second corner region. In a battery module of the second battery module type, the module positive pole is therefore arranged in the third corner region and the module negative pole in the first corner region, with the module poles arranged in mirror image about a mirror plane running transversely to the module longitudinal direction. In the case of mirror images about a mirror plane running perpendicular to the module cross section and parallel to the module longitudinal direction, in the second battery module type the module positive pole is located in the first corner region and the module negative pole in the third corner region. The two mirror images can be converted into each other by rotating the battery module by 180 ° about a vertical axis extending perpendicular to the cross section of the module.

Each battery module of the battery device is actually a first battery module type or a second battery module type such that no other battery module type exists within the battery device.

According to one advantageous embodiment, the battery modules can be arranged in the battery device such that the module longitudinal directions of the battery modules run parallel to one another. The battery modules adjacent parallel to the module longitudinal direction and/or transverse to the module longitudinal direction are alternately of a first battery module type and a second battery module type. It is thus possible to: the battery modules are arranged in the battery device such that the module poles to be connected to each other are close to each other, so that short connectors can be used.

In another embodiment, it can be provided that: the battery modules of the first battery module type and the battery modules of the second battery module type are arranged adjacent to each other in the battery device such that the module positive pole of the battery module of the first battery module type is arranged adjacent to the module negative pole of the battery module of the second battery module type and is electrically connected to the module negative pole by one of the connectors. By the adjacent positioning of the module poles to be connected to one another, the connectors required for the electrical connection are of relatively short construction and can be realized with little material expenditure, which is correspondingly cost-effective.

For example, each battery module can have a module length measured parallel to the module longitudinal direction and a module width measured transverse to the module longitudinal direction, wherein the module width is less than the module length. The spacing of the module poles of adjacent battery modules to be connected to each other is smaller than the module width. The connector that electrically connects the module positive electrode and the module negative electrode of two adjacent battery modules to each other is preferably shorter than the module width. In particular, the connector can be dimensioned such that it is at most half the width of the module. The connectors are preferably shorter than half the width of the module. Short connectors require a small amount of material, which reduces the manufacturing cost of the connector.

In another embodiment, the battery device can have an even number of battery modules and at least four battery modules. Here, the first half of the battery module can be of a first battery module type, while the second half of the battery module, i.e. all other battery modules, can be of a second battery module type. Furthermore, the battery modules can be arranged in the battery device such that the battery modules of the first battery module type and the battery modules of the second battery module type alternate parallel to the module longitudinal direction and transverse to the module longitudinal direction. Thereby, all battery modules within the series circuit can be electrically connected with a relatively short connector. In practice, the number of battery modules corresponds to an integer multiple of 4, so that the battery device therefore preferably has a number of 4, 8, 12, etc. battery modules connected in series in the series circuit.

The following further development is particularly advantageous, in which the module positive pole of the battery module of one battery module type forms the device positive pole and the module negative pole of the battery module of the other battery module type forms the device negative pole. In fact, the battery module can be disposed within the battery device at this time such that the device positive electrode and the device negative electrode are disposed adjacent to each other. This simplifies the electrical integration of the battery device in the battery system.

According to a further embodiment, provision can be made for: the first battery module at the first end of the series circuit is of a first battery module type and the second battery module at the second end of the series circuit is of a second battery module type. According to one refinement, it can also be provided that: the first battery module is disposed adjacent to the second battery module such that a module positive pole of the first battery module forms a device positive pole and is disposed adjacent to a module negative pole of the second battery module, which forms a device negative pole. This arrangement is also characterized by a simplified integration of the battery device into the battery system.

In another embodiment, it can be provided that: at least in one battery module, the battery cells have an odd number and form a 1P circuit. In the 1P circuit, all the battery cells are connected in series. In a 1P circuit, a relatively high voltage can be achieved at the battery module. According to an advantageous further development, it can be provided that: each battery module has two longitudinal module sides running parallel to the module longitudinal direction and spaced apart from one another transversely to the module longitudinal direction. Furthermore, the battery cell can be configured flat and have two end sides facing away from one another, wherein one end side has a cell negative electrode and the other end side has a cell positive electrode. Alternatively, both the positive electrode and the negative electrode can be provided on the same end side. In this case, however, the two poles are arranged in the region of the end regions which are spaced apart from one another as far as possible. The battery cells can then follow one another in the module longitudinal direction, so that the cell positive poles and the cell negative poles alternate at the respective module longitudinal sides. In this way, adjacent battery cells in the battery module can be connected to one another in series in a particularly simple manner.

In another embodiment, it can be provided that: at least in one battery module, the battery cells form a 2P circuit and have an odd number of pairs of battery cells. In a 2P circuit, every two battery cells are connected in parallel such that they form a battery cell pair. Further, in the 2P circuit, all the pairs of battery cells are connected in series. In the 2P circuit, a current intensity twice as high can be achieved with the same number of battery cells within the battery module, as compared to the 1P circuit.

According to an advantageous further development, provision can also be made here for: every two battery cells adjacent in the longitudinal direction of the module form a battery cell pair in which the two battery cells are connected in parallel, and wherein the cell cathodes of the two battery cells form the cell pair cathodes and the cell anodes of the two battery cells form the cell pair anodes. Furthermore, the battery cell pairs are arranged one after the other in the module longitudinal direction such that the cell pair positive pole and the cell pair negative pole alternate at each module longitudinal side. The production of the battery module is simplified by this type of construction.

Further important features and advantages of the invention emerge from the dependent claims, the figures and the associated description of the figures on the basis of the figures.

It goes without saying that the features mentioned above and those yet to be explained below can be used not only in the respectively mentioned combination but also in other combinations or alone without departing from the scope of the invention. The above-mentioned and below-listed components of the superordinate unit (for example, the individually indicated devices, facilities or apparatuses) can form individual components or parts of the unit or an integral region or section of the unit, even if this is shown differently in the figures.

Drawings

Preferred embodiments of the invention are illustrated in the figures and are explained in more detail in the following description, wherein the same reference numerals indicate identical or similar or functionally identical components.

Schematically showing:

figure 1 shows a top view of a battery device,

figure 2 shows a top view of a battery module of a first battery module type,

fig. 3 shows a top view of a battery module of a second battery module type.

Detailed Description

According to fig. 1, a battery device 1 comprises a plurality of battery modules 2, each of which has a plurality of battery cells 3. The battery cells 3 are arranged alongside one another in the module longitudinal direction 4 within each battery module 2. The battery cells 3 are designed to be flat and can be prismatic cells or pouch cells. The battery device 1 can form a traction battery for a battery electric vehicle. Such a traction battery can have a plurality of such battery devices 1 or at least one such battery device 1 and at least one further, in particular different, battery module 2.

The battery cells 3 are electrically connected to one another in each battery module 2, so that each battery module 2 has exactly one module positive pole 5 and exactly one module negative pole 6. The battery modules 2 are in turn arranged next to one another in the battery device 1 and are connected in series, so that they form a series circuit 7, which is represented by a dashed line in fig. 1. The series circuit 7 has exactly one device positive pole 8 and exactly one device negative pole 9 at the battery device 1. In the series circuit 7, two battery modules 2 following one another are electrically connected to one another by means of a module electrical connector 10. Here, each module connector 10 (hereinafter, may also be referred to as a connector 10) connects the module positive electrode 5 of one battery module 2 with the module negative electrode 6 of another battery module 2.

As can be seen from fig. 1 to 3, the battery modules 2 are configured as a cuboid, so that they have a rectangular module cross section parallel to the module longitudinal direction 4. In fig. 1 to 3, the module cross sections each extend parallel to the drawing plane. Within the battery modules 2, the battery cells 3 are electrically connected to each other such that each module positive electrode 5 and each module negative electrode 6 are located in diagonally opposite regions of each battery module 2. For example, in fig. 2 and 3, corner regions 11 associated with the four corners of a rectangular cross section are denoted by reference numerals, which follow each other in the circumferential direction of the battery module 2. The four corner regions 11 can follow each other in a clockwise direction and form a first corner region 11a, a second corner region 11b, a third corner region 11c and a fourth corner region 11d.

In the battery device 1, the battery modules 2 form a first battery module type 2a and a second battery module type 2b. The first and second battery module types 2a and 2b are different from each other in that: the module anode 5 and the module cathode 6 are arranged in mirror inversion. In the example of fig. 2, in the battery module 2 of the first battery module type 2a, the module positive electrode 5 is arranged in the fourth corner region 11d, and the module negative electrode 6 is arranged in the second corner region 11b, i.e. diagonally opposite to the module positive electrode 5. In contrast, according to fig. 3, in the battery module 2 of the second battery module type 2b, the module positive pole 5 is arranged in the third corner region 11c, and the module negative pole 6 is arranged in the first corner region 11a, i.e. diagonally opposite to the module positive pole 5. The

module poles

5, 6 are therefore mirrored in both battery module types 2a and 2b with respect to a mirror plane 12, which runs perpendicular to the module longitudinal direction 4 and which can also be referred to as first mirror plane 12. In both battery module types 2a, 2b, the

module poles

5, 6 are also arranged mirror-inverted with respect to a mirror plane 13, which runs parallel to the module longitudinal direction 4 and perpendicular to the module cross section and can also be referred to as second mirror plane 13. The second battery module type 2b shown in fig. 3, which is produced by mirroring at the first mirror plane 12, can be converted into the second battery module type 2b produced by mirroring at the second mirror plane 13 by rotating 180 ° about a rotational axis running perpendicular to the module cross section. In this regard, the two second battery module types 2b are identical.

According to fig. 1, the battery modules 2 are arranged in the battery device 1 such that the module longitudinal directions 4 of the battery modules run parallel to one another. Furthermore, the battery modules 2 adjacent in parallel to the module longitudinal direction 4 are alternately of a first battery module type 2a and a second battery module type 2b. Furthermore, the battery modules 2 laterally adjacent to the module longitudinal direction 4 are alternately of a first battery module type 2a and a second battery module type 2b. In particular, the battery modules 2 are arranged in the battery device 1 such that the battery modules 2 following one another in the series circuit 7 are alternately of a first battery module type 2a and a second battery module type 2b.

Therefore, the battery modules 2 of the first battery module type 2a and the battery modules 2 of the second battery module type 2b are disposed adjacent to each other in the battery device 1 such that the module positive electrode 5 of the battery module 2 of the first battery module type 2a is disposed adjacent to the module negative electrode 6 of the battery module 2 of the second battery module type 2b so as to be electrically connected thereto with one of the connectors 10. In fig. 1, a module length 14, measured parallel to the module longitudinal direction 4, and a module width 15, measured transversely to the module longitudinal direction 4, representing all battery modules 2, are introduced into one of the battery modules 2. At this point it can be seen that: each connector 10 electrically connecting the module positive electrodes 5 and the module negative electrodes 6 of two adjacent battery modules 2 to each other is shorter than a module width 15, which in turn is smaller than a module length 14.

In the example of fig. 1, the battery device 1 has an even number of battery modules 2, wherein the number of battery modules 2 is at least four. In the example shown, exactly eight battery modules 2 are provided. The first half of the battery module 2 is here a first battery module type 2a, while all other battery modules 2, i.e. the second half of the battery module 2, are a second battery module type 2b. Therefore, in the example of fig. 1, four battery modules 2 of a first battery module type 2a and four battery modules 2 of a second battery module type 2b are provided. Furthermore, the battery modules 2 are arranged in the battery device 1 such that the battery modules 2 of the first battery module type 2a and the battery modules 2 of the second battery module type 2b alternate parallel to the module longitudinal direction 4 and transverse to the longitudinal direction 4. There are also provided: the module positive electrode 5 of the battery module 2 of one battery module type 2a, 2b forms the device positive electrode 8. In the example of fig. 1, the device positive electrode 8 is formed by the module positive electrode 5 of the battery module 2 of the first battery module type 2 a. The module negative pole 6 of the battery module 2 of the other battery module type 2a, 2b forms the device negative pole 9. In the example of fig. 1, the device negative electrode 9 is formed by the module negative electrode 6 of the battery module 2 of the second battery module type 2b. The battery module 2 is arranged here such that the device positive electrode 8 and the device negative electrode 9 are arranged next to one another.

The battery modules 2 of the battery device 1 include a first battery module 2' and a second battery module 2 ″. The first battery module 2' is located at a first end 16 of the series circuit 7, while the second battery module 2 ″ is located at a second end 17 of the series circuit 7. Here, the first battery module 2' is one battery module type 2a, 2b, and the second battery module 2 ″ is another battery module type 2a, 2b. In the example of fig. 1, the first battery module 2' is a first battery module type 2a, and the second battery module 2 ″ is a second battery module type 2b. Furthermore, the first battery module 2 'and the second battery module 2 ″ are arranged adjacent to one another such that the module positive pole 5 of the first battery module 2' forms the device positive pole 8 and is arranged adjacent to the module negative pole 6 of the second battery module 2 ″ which forms the device negative pole 9.

At least in one battery module 2, the battery cells 3 can have an odd number, wherein all battery cells 3 are connected in series, thereby forming a 1P circuit. It is also conceivable: at least in one battery module 2, every second battery cell 3 is connected in parallel and forms a battery cell pair 3'. The two battery cells 3 of each battery cell pair 3' are connected in parallel. All the pairs 3' of battery cells of each battery module 2 are connected in series. Thereby, the battery cells 3 form a 2P circuit in the battery module 2. Furthermore, each battery module 2 then has an odd number of battery cell pairs 3'.

According to fig. 2 and 3, each battery module 2 has two module

longitudinal sides

18 and 19, which each run parallel to the module longitudinal direction 4 and are spaced apart from one another transversely to the module longitudinal direction 4. The battery unit 3 is flat and has two end sides 20, 21 facing away from each other. One end side 20 has a cell cathode 22 and the other end side 21 has a cell anode 23. The end sides 20, 21 and the cell poles 22, 23 are provided with reference numerals in fig. 2 and 3 only in a purely exemplary and representative manner. In any case, the battery cells 3 are arranged one behind the other in the module longitudinal direction 4, such that the cell anodes 22 and the cell cathodes 23 alternate at the respective module

longitudinal sides

18, 19. This applies to the configuration in which the battery cells 3 of the battery module 2 form a 1P circuit.

On the other hand, if the battery cells 3 form a 2P circuit within the battery module 2, the adjacent battery cells 2 respectively define a battery cell pair 3' in which two battery cells 3 are connected in parallel. Thus, in each battery cell pair 3, the cell positive electrodes 22 of the two battery cells 3 form a cell pair positive electrode 22 'at one end side of the battery cell pair 3', and the cell negative electrodes 23 of the two battery cells 3 form a cell pair negative electrode 23 'at the other end side of the battery cell pair 3'. Within the battery module 2, the battery cell pairs 3' are arranged one behind the other in the module longitudinal direction 4, such that the cell pair positive pole 22' and the cell pair negative pole 23' alternate at the respective module

longitudinal side

18, 19. Also applicable here are: in fig. 2 and 3, the cell pair positive pole 22 'and the cell pair negative pole 23' are provided with reference numerals in a representative and purely exemplary manner only.

Claims

1. A battery device (1) for a battery electric vehicle,

-having a plurality of battery modules (2) each having a plurality of battery cells (3) which are arranged alongside one another in a module longitudinal direction (4),

-wherein the battery cells (3) in each battery module (2) are electrically connected to each other such that each battery module (2) has exactly one module positive pole (5) and exactly one module negative pole (6),

-wherein battery modules (2) are arranged alongside each other in the battery device (1), connected in series and forming a series circuit (7) having exactly one device positive pole (8) and exactly one device negative pole (9) at the battery device (1),

-wherein in the series circuit (7) every two battery modules (2) following each other are electrically connected to each other by means of an electrical connector (10) which electrically connects the module positive pole (5) of one battery module (2) with the module negative pole (6) of the other battery module (2),

-wherein the battery modules (2) are configured as rectangles in a module cross section running parallel to the module longitudinal direction (4),

-wherein the battery cells (3) are electrically connected in each battery module (2) such that each module positive electrode (5) and each module negative electrode (6) are located in diagonally opposite regions (11 a, 11b, 11c, 11 d) of each battery module (2),

-wherein the battery modules (2) form a first battery module type (2 a) and a second battery module type (2 b), which differ from each other in that the module positive pole (5) and the module negative pole (6) are arranged mirror-inverted.

2. The battery device (1) according to claim 1,

it is characterized in that the preparation method is characterized in that,

-battery modules (2) are arranged in the battery device (1) such that the module longitudinal directions (4) of the battery modules run parallel to each other,

-battery modules (2) adjacent parallel to the module longitudinal direction (4) and/or transverse to the module longitudinal direction (4) are alternately of the first battery module type (2 a) and of the second battery module type (2 b).

3. The battery device (1) according to claim 1 or 2,

it is characterized in that the preparation method is characterized in that,

-in the battery device (1), the battery modules (2) of the first battery module type (2 a) and the battery modules (2) of the second battery module type (2 b) are arranged adjacently such that the module positive pole (5) of the battery module (2) of the first battery module type (2 a) is arranged adjacently to the module negative pole (6) of the battery module (2) of the second battery module type (2 b) and is electrically connected with the module negative pole of the battery module of the second battery module type with one of the connectors (10).

4. The battery device (1) according to one of claims 1 to 3,

it is characterized in that the preparation method is characterized in that,

-each battery module (2) having a module length (14) measured parallel to the module longitudinal direction (4) and a module width (15) measured transverse to the module longitudinal direction (4), the module width being smaller than the module length (14),

-the connector (10) electrically connecting the module positive pole (5) and the module negative pole (6) of two adjacent battery modules (2) to each other is shorter than the module width (15).

5. The battery device (1) according to one of claims 1 to 4,

it is characterized in that the preparation method is characterized in that,

-the battery device (1) has an even number of battery modules (2) and at least four battery modules (2),

-a first half of the battery modules (2) is of the first battery module type (2 a) and a second half of the battery modules (2) is of the second battery module type (2 b),

-battery modules (2) are arranged in the battery device (1) such that battery modules (2) of the first battery module type (2 a) and battery modules (2) of the second battery module type (2 b) alternate parallel to the module longitudinal direction (4) and transverse to the module longitudinal direction (4).

6. The battery device according to claim 5, wherein the battery pack,

it is characterized in that the preparation method is characterized in that,

-the module positive electrode (5) of a battery module (2) of one battery module type (2 a, 2 b) forms the device positive electrode (8),

-the module negative pole (6) of a battery module (2) of another battery module type (2 a, 2 b) forms the device negative pole (9),

-the device positive pole (8) and the device negative pole (9) are arranged adjacent to each other.

7. The battery device (1) according to one of claims 1 to 6,

it is characterized in that the preparation method is characterized in that,

-a first battery module (2') located at a first end (16) of the series circuit (7) is of a battery module type (2 a, 2 b),

-a second battery module (2') located at a second end (17) of the series circuit (7) is of another battery module type (2 a, 2 b),

-the first battery module (2 ') is arranged adjacent to the second battery module (2 ") such that the module positive pole (5) of the first battery module (2') forms the device positive pole (8) and is arranged adjacent to the module negative pole (6) of the second battery module (2") which forms the device negative pole (9).

8. The battery device (1) according to one of claims 1 to 7,

it is characterized in that the preparation method is characterized in that,

-at least in one battery module (2), the battery cells (3) have an odd number and form a 1P circuit.

9. The battery device (1) according to claim 8,

it is characterized in that the preparation method is characterized in that,

each battery module (2) having two module longitudinal sides (18, 19) running parallel to the module longitudinal direction (4) and spaced apart from one another transversely to the module longitudinal direction (4),

the battery cell (3) is flat and has two end sides (20, 21) facing away from each other, wherein one end side (20) has a cell negative pole (22) and the other end side (21) has a cell positive pole (23),

-the battery cells (3) follow each other in the module longitudinal direction (4) such that cell positive poles (22) and cell negative poles (23) alternate at each module longitudinal side (18, 19).

10. The battery device (1) according to one of claims 1 to 9,

it is characterized in that the preparation method is characterized in that,

-at least in one battery module (2), the battery cells form a 2P circuit and have an odd number of battery cell pairs (3').

11. The battery device (1) according to claim 10,

it is characterized in that the preparation method is characterized in that,

the battery cell (3) is flat and has two end sides (20, 21) facing away from each other, wherein one end side (20) has a cell positive pole (22) and the other end side (21) has a cell negative pole (23),

-every second battery cell (3) adjacent in the module longitudinal direction (4) forms a battery cell pair (3 '), in which the two battery cells (3) are connected in parallel, and wherein the cell anodes (22) of the two battery cells (3) form a cell pair anode (22 ') and the cell cathodes (23) of the two battery cells (3) form a cell pair cathode (23 '),

-cell pairs (3 ') follow each other in the module longitudinal direction (4) such that cell pair positive poles (22 ') and cell pair negative poles (23 ') alternate at each module longitudinal side (18, 19).