Battery device

Abstract

The invention relates to a battery arrangement (1) comprising a plurality of identically oriented battery cells (2), a first electrically conductive track (3) and a second electrically conductive track (4), the longitudinal axes (15) of the battery cells being arranged in parallel, wherein the first electrically conductive track (3) and the second electrically conductive track (4) are arranged on the same side of the battery cells (2) along the respective longitudinal axes (15), wherein the respective positive poles (21) of the battery cells (2) are connected with the first electrically conductive track (3) by means of first bonding connections (5), and wherein the respective negative poles (22) of the battery cells (2) are connected with the second electrically conductive track (4) by means of second bonding connections (6).

Description

Technical Field

[0001] The present invention relates to a battery device having a bonding connection for electrically connecting to a battery cell. Background Technology

[0002] Battery modules used as energy storage devices in vehicles typically consist of multiple individual battery cells (such as lithium-ion battery cells). Electrical connections are made at the terminals of each battery cell via contact elements, which are usually connected to the battery cell using a resistance welding process. However, this resistance welding connection is costly to manufacture and limits the choice of materials for the contact elements. Summary of the Invention

[0003] In contrast, the battery device according to the invention, possessing the features of the invention, offers the advantage of improved electrical connection of the battery cells, enabling rapid and simple assembly, excellent electrical characteristics, and low cost. According to the invention, this is achieved by a battery device comprising multiple battery cells, a first conductive rail (Stromschiene), and a second conductive rail. The longitudinal axes of the battery cells are arranged parallel to each other. Furthermore, all battery cells are arranged in the same orientation, meaning that the positive electrodes of the battery cells point in the same direction about the longitudinal axis. In particular, all battery cells are arranged side-by-side with each other, preferably at the same height, i.e., such that all positive electrodes are located in a common plane. Here, the first and second conductive rails are arranged about the same side of the battery cell about the longitudinal axis. This means that the two conductive rails, preferably constructed in the form of metal plates, are not arranged on opposite ends of the battery cells, but rather on exactly one side of the battery cell. Particularly preferably, the two conductive rails are arranged in a common plane perpendicular to the longitudinal axis and preferably substantially in the plane of the positive electrode.

[0004] Here, the positive terminal of the battery cell is connected to the first conductive rail via a first bonding connection. The negative terminal of the battery cell is connected to the second conductive rail via a second bonding connection. Here, a conductive connection including wire-like connecting elements is considered a bonding connection, wherein the wire-like connecting elements are respectively bonded to one of the conductive rails and one of the terminals of the battery cell. Preferably, it involves an ultrasonic bonding connection manufactured using ultrasound. More preferably, the bonding connection is a so-called ultrasonic wedge-wedge bonding connection. Here, the wire-like connecting elements of the bonding connection provide a certain degree of flexibility or adaptability. This ensures a reliable and durable connection, even when vibration or shock is applied to the battery device.

[0005] Another advantage is that battery devices can be assembled using simple, cost-effective, and low-maintenance machine and equipment techniques, i.e., bonding connections can be manufactured. Furthermore, cost-effective materials with particularly good electrical properties (e.g., high conductivity) can be used for bonding connections.

[0006] Of particular advantage, the single-sided connection of the battery cell also has benefits. On the one hand, this keeps the manufacturing process very simple, cost-effective, and space-saving, since accessibility to the battery cell is only required from one direction. On the other hand, the arrangement of conductive rails bonded to only one side of the battery cell allows for a particularly compact structure of the battery device itself, since, for example, it is not necessary to connect the battery cell from both sides. In particular, single-sided connection avoids the costly handling and rotation of the battery cell during manufacturing.

[0007] The preferred embodiments include preferred extensions of the present invention.

[0008] Preferably, the two conductive rails are located on the side of the battery cell where the positive electrode is located. Here, every other bonding connection is connected to the shoulder region of the battery cell forming the negative electrode, which surrounds the corresponding positive electrode. Preferably, the second bonding connection is arranged tangentially with respect to the outer periphery of the battery cell to achieve optimal utilization of the narrow shoulder region. In particular, the battery cell is configured such that each battery cell has a single positive electrode, which is circularly constructed and located only on exactly one end side of the battery cell. Furthermore, each battery cell has exactly one negative electrode, which is formed, in particular, through the housing of the battery cell. The negative electrode extends across the shoulder region surrounding the positive electrode, the outer periphery of the battery cell (i.e., especially the housing region), and the end side of the battery cell opposite the positive electrode. Here, the shoulder region is constructed, in particular, in a non-insulated manner. For example, the insulation on the shoulder region can be removed before establishing the second bonding connection. Due to this arrangement, in addition to the compact geometry of the battery device, particularly simple manufacturability can be achieved. Since all the components to be bonded are placed side by side and are accessible from the same direction, this arrangement can be handled particularly simply when manufacturing the bonding connection, where, in particular, there is no need to rotate the battery cell.

[0009] Particularly preferably, each bonding connection comprises copper and / or aluminum. Specifically, the wire-like connecting elements of the bonding connection are formed of copper and / or aluminum. This provides a particularly cost-effective bonding connection with optimal electrical characteristics, such as high conductivity.

[0010] Preferably, the thickness of each bonding connection is at least 100 μm, and preferably a maximum of 500 μm. Here, the minimum and / or maximum dimension of the bonding connection in the cross-section of the bonding connection is considered as the thickness. For example, in the case of a bonding connection with a circular cross-section, i.e., in the case of a wire bonding connection, the thickness corresponds to the diameter of the circular cross-section. Preferably, the bonding connection involves a so-called thick wire bonding connection.

[0011] Particularly preferably, the cross-section of each bonding connection is designed such that the bonding connection functions as a fuse. Here, when a predefined maximum current is exceeded, the fuse interrupts the current flow from and / or to the battery cell. Specifically, the minimum cross-section of each bonding connection is considered here. This means that if, for example, a predefined maximum current is exceeded due to a short circuit in the battery device, each bonding connection exceeding that maximum current is broken, thereby interrupting the electrical connection between the battery cell and the corresponding conductive rail. Therefore, the electrical connection of the battery cell via the bonding connections provides a particularly simple and cost-effective possibility for implementing overcurrent protection devices in the battery device.

[0012] Preferably, the battery device further includes a cell retainer, which has a housing for each cell. This housing is configured to hold exactly one cell respectively. Here, the cell retainer provides a defined hold of the cell cells relative to each other. Through a special one-sided connection of the cell cells via bonding, the cell retainer can be constructed in a particularly simple and cost-effective manner, as there is a low requirement for the accessibility of the cell cells. Preferably, the cell retainer is formed of a non-conductive material, especially plastic.

[0013] Preferably, the battery cell holding device completely surrounds each battery cell except for exactly one end of the battery cell, particularly the end where the bonding connection and conductive rail (i.e., the positive terminal of the battery cell) are located. In other words, the battery cell holding device completely surrounds the entire periphery of each battery cell and exactly one end. Preferably, the receiving portion of the battery cell holding device is constructed as a blind hole corresponding to the geometry of the battery cell. This means that the battery cell can be easily pushed into the receiving portion without considering the further accessibility of the unconnected end of the battery cell. Preferably, the battery cell holding device has a one-piece battery cell holding device element in which multiple receiving portions are constructed to accommodate the battery cells. Preferably, the battery cell holding device additionally has a cover that can be connected to the battery cell holding device element and that partially covers exactly any one of the exposed end of the battery cell to secure the battery cell in the receiving portion.

[0014] More preferably, for each battery cell, the battery cell holding device has a wall disposed between the positive and negative electrodes. Here, the wall forms a shield in the region between the first and second bonded connections. Preferably, this wall is part of the cover of the battery cell holding device, which is removable and configured to secure the battery cell in the receiving portion. Here, the wall achieves the following effect: in the event of bonded connection damage, it prevents short circuits between the side-by-side first and second bonded connections. In particular, when a bonded connection breaks, the wall forms a non-conductive barrier that prevents bond remnants from the broken bonded connection from contacting the nearest bonded connection.

[0015] Preferably, the height of the wall is designed such that the minimum length of the virtual line extending across the wall from the negative electrode to the positive electrode or vice versa is greater than the maximum bonding length of each of the bonded connections. Here, the maximum dimension of the wall in the direction parallel to the longitudinal axis of the battery cell is considered the height. In the event of a bonded connection breakage, particularly at one of the bottom points (Fuβpunkte) of the bonded connection, the wall prevents bonding residues from contacting adjacent positive or negative electrodes or adjacent bonded connections.

[0016] More preferably, the highest point of the wall above the respective battery cell about the longitudinal axis is arranged higher than the highest point of each bonding connection above the respective battery cell. This means that the bonding connections are always arranged lower than the wall about the longitudinal axis. Therefore, the wall protrudes beyond the bonding connections in a direction parallel to the longitudinal axis and above the battery cell. This enables contact protection of the bonding connections in a simple and cost-effective manner. Especially during the transportation of the battery device or in the event of an impact or drop (Sturz) on the battery device, thus reducing the probability of damage to the bonding connections.

[0017] More preferably, for each bonded connection, the battery cell holding device has two walls, with each bonded connection arranged between the two walls. This provides particularly effective contact protection for the bonded connections, especially when each wall is higher than the highest point of each bonded connection. This makes it difficult, for example, during manual operation or transport of the battery device, for objects to come into contact with the bonded connections, thereby causing damage, short circuits, etc.

[0018] Preferably, the battery cells are constructed in a non-insulated manner. This means that the battery cells do not have any insulating portion, which is at least partially located on the outside of each battery cell for contact protection. In particular, no insulating shrink sleeve is provided on the outside of the battery cells. Instead, the insulating portion is preferably formed by a battery cell holding device made of a non-conductive material. This allows for the particularly easy-to-manufacture electrical connection of the battery cell, especially the negative electrode, by means of a bonding connection.

[0019] Preferably, each bonding connection is a line bonding connection or a strip bonding connection. Here, a bonding connection using a line with a circular cross-section is considered a line bonding connection. A bonding connection using a strip with a rectangular cross-section is considered a strip bonding connection.

[0020] Particularly preferably, the battery device includes a plurality of first conductive rails and / or a plurality of second conductive rails. Thus, multiple battery cells can be connected in series and / or in parallel. Specifically, here, not only the positive electrode but also the negative electrode can be connected to the first conductive rails. Similarly, not only the positive electrode but also the negative electrode can be connected to the second conductive rails, so that, for example, multiple battery cells can be connected in series. Attached Figure Description

[0021] The present invention will now be described with reference to the accompanying drawings and embodiments. In the drawings, components with the same function are labeled with the same reference numerals. Here are:

[0022] Figure 1 A view of a battery device according to a preferred embodiment of the present invention is shown;

[0023] Figure 2 Show Figure 1 Detailed cross-sectional view of the battery device. Detailed Implementation

[0024] Figure 1 A detailed top view of a battery device 1 according to a preferred embodiment of the present invention is shown. Figure 2 The middle shows Figure 1 Detailed cross-sectional view of battery device 1.

[0025] The battery device 1 includes a plurality of cylindrical battery cells 2 and a battery cell holding device 7. For each battery cell 2, the battery cell holding device has a receiving portion 70 in which the battery cell 2 is housed. The battery cells 2 are cylindrical. Here, all battery cells 2 are arranged parallel to each other along their longitudinal axes 15. Furthermore, all battery cells 2 are oriented identically, meaning that the positive electrode 21 points in the same direction.

[0026] Here, each battery cell 2 has a single positive electrode, which is circularly constructed and located on exactly one end of the battery cell (see [link]). Figure 2 In addition, each battery cell 2 has exactly one negative electrode 22 that extends over the shoulder region 20 of the battery cell 2, the housing region and the end side of the battery cell 2 opposite to the positive electrode 21.

[0027] The battery cell holding device 7 includes a battery cell holding device element 78 in which the battery cell 2 is arranged in a receiving portion 70. The receiving portion 70 is constructed as a cylindrical blind hole, in which only the end side with the positive electrode 21 of the battery cell 2 is exposed. Furthermore, the battery cell holding device 7 includes a cover 77 that is directly adjacent to and connected to the battery cell holding device element 78 in the direction of the longitudinal axis 15. Here, the cover 77 covers the exposed end side of the battery cell 2 with the positive electrode 21 and secures the battery cell 2 within the receiving portion 70.

[0028] Furthermore, the battery device 1 includes a first conductive rail 3 and a second conductive rail 4, which are constructed as plates and made of conductive material, such as copper or aluminum. The two conductive rails 3 and 4 are arranged about the longitudinal axis 15 on the same side of the battery cell 2, i.e., on the side of the positive electrode 21. Here, the two conductive rails 3 and 4 are integrated into the cover 77 of the battery cell holding device 7. (As in...) Figure 1 As can be seen, a row of battery cells 2 is arranged between two adjacent conductive rails 3 and 4.

[0029] Conductive rails 3 and 4 are used for parallel and series connections of multiple battery cells 2, and for current transmission from or to battery cells 2.

[0030] Here, the corresponding positive electrode 21 of battery cell 2 is connected to the first conductive rail 3 via the first bonding connection 5. Furthermore, the corresponding negative electrode 22 of battery cell 2 is connected to the second conductive rail 4 via the second bonding connection 6.

[0031] Here, the first bonding connection 5 and the second bonding connection 6 are both formed of aluminum.

[0032] The bonding connections 5 and 6 relate to linear bonding connections, characterized in that the wires having circular cross-sections are bonded to two contact partners by means of ultrasonic wedge-wedge-bonden bonding, namely bonded to one of the conductive rails 3 and 4 and one of the poles 21 and 22.

[0033] Here, the first bonding connection 5 is centrally bonded to the positive electrode 21 on the battery side. The second bonding connection 6 is bonded to the shoulder region 20 of the battery cell 2 that forms the negative electrode 22 on the battery side. Figure 1 As can be seen, the bonding line of the second bonding connection 6 extends tangentially about the cylindrical battery cell 2.

[0034] Here, the electrical connection of battery cell 2 via bonding connections 5 and 6 and by means of conductive rails 3 and 4 arranged on one side offers many advantages. In particular, the unilateral arrangement and operation of all components facilitating electrical connection allows for particularly simple assembly of battery device 1, as all assembly steps can be performed from exactly one side of battery device 1. Furthermore, this enables a particularly compact geometry of battery device 1, since space is required for accessibility from only one direction.

[0035] Furthermore, the bonding connections 5 and 6 offer advantages in the operation of the battery device 1. Thus, the bonding connections 5 and 6 allow for some compensation of the relative movement between the battery cell 2 and the conductive rails 3 and 4, for example, due to different thermal expansion. By using aluminum as the material for the bonding connections 5 and 6, optimal electrical characteristics with low transmission losses can also be achieved. Moreover, the bonding connections 5 and 6 can be manufactured particularly cost-effectively and simply, especially due to the availability of cost-effective aluminum and the cost-effective machine and equipment components that can be used to manufacture the bonding connections 5 and 6.

[0036] Furthermore, the bonding connections 5 and 6 allow for the implementation of overcurrent protection devices on the battery device 1 in a simple and cost-effective manner. For this purpose, the minimum cross-sectional area of ​​each bonding connection 5 and 6 (i.e., the minimum diameter of each wire in the bonding connection 5 and 6) is sized such that each bonding connection 5 and 6 is designed as a fuse. In the event of a predefined maximum current flowing through the bonding connection 5 and 6, the bonding connection 5 and 6 automatically burns out due to their respective dimensions, thereby interrupting the current flow through the bonding connection 5 and 6. Specifically, for this purpose, the diameter of each bonding connection 5 and 6 is at least 100 μm and at most 500 μm, preferably 300 μm.

[0037] In order to provide mechanical protection for the bonding connections 5, 6 and thus provide a particularly durable battery device 1, the cover 77 of the battery cell holding device 7 includes a plurality of walls 71, which extend parallel to the longitudinal axis 15.

[0038] As in Figure 2 As can be seen, the height 72 of each wall 71, measured from the connection plane 76 between the cover 77 and the battery cell holding device element 78, is designed such that the minimum length of the conceived virtual line 75 connecting the negative electrode 22 and the positive electrode 21 to each other through the wall 71 is greater than the maximum bonding length 51 of each of the bonding connections 5 and 6 (see [link]). Figure 1 Thus, each wall 71 provides shielding, thereby preventing the wire block from unintentionally connecting to adjacent poles 21 and 22 if bonding connections 5 and 6 are broken. This avoids short circuits even if bonding connections 5 and 6 are broken.

[0039] Furthermore, the height 72 of the wall 71 is designed such that the highest point 73 of the wall 71 about the longitudinal axis 15 is higher than the highest point 52 of each bonding connection 5, 6 above the corresponding battery cell 2. This provides protection for the bonding connections 5, 6 from mechanical impacts, preventing damage to the bonding connections 5, 6, for example, during the transport of the battery assembly 1. Figure 2 As shown in the diagram, this prevents larger objects 80 from contacting the bonded connections 5 and 6. In particular, this also provides contact protection to prevent unintentional human contact with the bonded connections 5 and 6. (As shown in...) Figure 1 and Figure 2 As can be seen from the diagram, wall 71 is advantageously positioned on both sides of each bonded connection.

Claims

1. A battery device (1), the battery device comprising: - Multiple battery cells (2) with the same orientation, the longitudinal axes (15) of the battery cells being arranged in parallel. - First conductive rail (3). - Second conductive rail (4) - Wherein, the first conductive rail (3) and the second conductive rail (4) are arranged on the same side of the battery cell (2) along their respective longitudinal axes (15), - Wherein, the corresponding positive electrode (21) of the battery cell (2) is connected to the first conductive rail (3) by means of a first bonding connection (5), - Wherein, the corresponding negative electrode (22) of the battery cell (2) is connected to the second conductive rail (4) by means of a second bonding connection (6), Two conductive rails (3, 4) are located on the side of the battery cell (2) where the positive electrode (21) is located, wherein each second bonding connection (6) is connected to the following shoulder region (20) of the battery cell (2): the shoulder region (20) forms the negative electrode (22) and surrounds the positive electrode (21). The battery device further includes a battery cell holding device (7), wherein the battery cell holding device (7) has a wall (71) for each battery cell (2) as follows: the wall (71) forms a shield in the region between the first bonding connection (5) and the second bonding connection (6) between the positive electrode (21) and the negative electrode (22).

2. The battery device (1) according to claim 1, wherein, Each bonding connection (5, 6) has copper and / or aluminum.

3. The battery device (1) according to claim 1 or 2, wherein, The thickness (50) of each bonded connection (5, 6) is at least 100 µm.

4. The battery device (1) according to claim 3, wherein, The thickness (50) of each bonded connection (5, 6) is a maximum of 500µm.

5. The battery device (1) according to claim 1 or 2, wherein, The cross-section of each bonding connection (5, 6) is designed such that each bonding connection (5, 6) is designed as a fuse that interrupts current flow when a predefined maximum current is exceeded.

6. The battery device (1) according to claim 1 or 2, wherein, The battery cell holding device (7) has a receiving portion (70) for holding the battery cell (2) for each battery cell (2).

7. The battery device (1) according to claim 6, wherein, Except for exactly one end (25) of the battery cell (2), the battery cell holding device (7) completely surrounds each battery cell (2).

8. The battery device (1) according to claim 1 or 2, wherein, The height (72) of the wall (71) is designed such that the minimum length of the virtual line (75) from the negative electrode (22) to the positive electrode (21) or vice versa across the wall (71) is greater than the maximum bonding length (51) of each of the bonding connections (5, 6).

9. The battery device (1) according to claim 1 or 2, wherein, The highest point (73) of the wall (71) above the corresponding battery cell (2) about the longitudinal axis (15) is higher than the highest point (52) of each bonding connection (5, 6) above the corresponding battery cell (2).

10. The battery device (1) according to claim 1 or 2, wherein, Each bonded connection (5, 6) is arranged between the two walls (71).

11. The battery device (1) according to claim 1 or 2, wherein, The battery cell (2) is constructed in a non-insulated manner.

12. The battery device (1) according to claim 1 or 2, wherein, Each bonding connection (5, 6) is either a line bonding connection or a band bonding connection.

13. The battery device (1) according to claim 1 or 2, the battery device comprising a plurality of first conductive rails (3) and / or a plurality of second conductive rails (4), the plurality of first conductive rails (3) and / or the plurality of second conductive rails (4) being used to connect a plurality of battery cells (2) in series and / or to connect a plurality of battery cells (2) in parallel.

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