Battery module

Abstract

Battery module (1) with a plurality of electrically interconnected individual cells (2a, 2b), wherein the individual cells (2a, 2b) each have pole contacts (3, 4) with a first and a second polarity, wherein the individual cells (2a, 2b) are connected to a carrier plate (5) in such a way that the respective pole contacts (3, 4) penetrate the carrier plate (5), wherein the pole contacts (3) with the first polarity of at least two individual cells (2a) are each electrically conductively and mechanically firmly connected to a first cell connector (6.1) and the pole contacts (4) with the second polarity of at least two further individual cells (2b) are each electrically conductively and mechanically firmly connected to a second cell connector (6.2), wherein the carrier plate (5) is made of an electrically non-conductive material on which the cell connectors (6.1, 6.2) rest directly, and the carrier plate (5) in the region between the first and the second cell connector (6.1, 6.2) has a web (7) which is configured such that in the event of deformation of the carrier plate (5), electrical contact between the first and the second cell connector (6.1, 6.2) is prevented, characterized in that the individual cells (2a, 2b) are designed as flat cells or pouch cells, each with flag-like pole contacts (3, 4), and the cell connectors (6.1, 6.2) are essentially plate-shaped, and in that the cell connectors (6.1, 6.2) have slots (11) for the respective pole contacts (3, 4) of the individual cells (2a, 2b) to penetrate.

Description

[0001] A battery module with several electrically interconnected individual cells according to the preamble of patent claim 1 is considered. The arrangement of such battery modules in a stable housing results in the traction battery of an electrically powered motor vehicle.

[0002] From DE 10 2008 034 868 A1 or DE 10 2008 034 697 A1, battery modules with several electrically interconnected individual cells are known. If the motor vehicle with this battery module has an accident, a force acting on the battery module can lead to electrical contact between the two pole contacts of an individual cell, which results in the risk of an electrical short circuit. Therefore, according to DE 10 2008 034 697 A1, a support element is arranged between the two pole contacts of the individual cells. From DE 10 2008 034 868 A1, it is known to equip a heat-conducting plate assigned to the individual cells with force transmission elements, which interact with flat elements arranged above them, such asa battery housing or an electronic component, distributes a force acting from above on the battery module across all the individual cells, thus avoiding a direct force acting on one or more pole contacts of a single cell. A battery module of this type is known from DE 10 2013 021 639 A1.

[0003] The object of the invention is to provide a particularly simple and space-saving design for a battery module which prevents an electrical short circuit when a force is applied to the battery module.

[0004] The problem is solved by the features of patent claim 1.

[0005] A battery module is provided with a plurality of electrically interconnected individual cells, wherein the individual cells each have pole contacts with a first and a second polarity, wherein the individual cells are connected to a carrier plate in such a way that the respective pole contacts penetrate the carrier plate, wherein the pole contacts with the first polarity of at least two individual cells are each electrically conductively and mechanically firmly connected to a first cell connector and the pole contacts with the second polarity of at least two further individual cells are each electrically conductively and mechanically firmly connected to a second cell connector, wherein the carrier plate is made of an electrically non-conductive material on which the cell connectors rest directly, and the carrier plate has a web in the region between the first and the second cell connector, which web is configured in such a waythat in the event of deformation of the carrier plate, electrical contact between the first and second cell connectors is prevented. According to the invention, the individual cells are designed as flat cells or pouch cells, each with flag-like pole contacts, and the cell connectors are essentially plate-shaped, and the cell connectors have slots for the respective pole contacts of the individual cells to penetrate. The battery module is very space-saving, since only a relatively thin carrier plate made of electrically non-conductive material is required as a mechanical support and electrical insulator, and the two or more electrical cell connectors resting directly on it. In addition, a particularly simple arrangement results, in that only the pole contacts with a respective polarity of two or more individual cells each need to be connected to the respective cell connectors.to establish the electrical conduction and mechanical strength of the battery module. For example, the positive pole of two or more first individual cells is connected to the first cell connector, and the negative pole of two or more second individual cells—different from the first individual cells—is connected to the second cell connector.

[0006] This advantageously results in a particularly secure connection. High electrical currents can occur, especially when individual cells are connected in parallel, as is the case here with the use of cell connectors. And here, an electrical short circuit between the two adjacent cell connectors is reliably prevented by the web arranged between them. Just like the carrier plate itself, the webs are also made of an electrically non-conductive material. This results in reliable electrical separation of the cell connectors, which are each connected to different polarities of the two or more individual cells. Even if the carrier plate is severely deformed in the event of an accident between the motor vehicle and the battery module, causing the cell connectors to shift, the webs reliably prevent electrical contact between cell connectors with different polarities.

[0007] In addition, the webs can be designed to be relatively small and thin, saving material, since they do not absorb or transmit any force acting on the battery module, but only have to prevent electrical contact between the respective cell connectors.

[0008] A particularly simple design solution is achieved by the inventive design of the individual cells as flat cells or pouch cells, each with flag-like, i.e., flat and elongated, pole contacts and with essentially plate-shaped cell connectors, if the cell connectors have slots for the penetration of the respective pole contacts of the individual cells. Thus, after penetrating the carrier plate, only a further penetration of the corresponding slots in the cell connectors is necessary for the respective pole contacts to establish a connection.

[0009] A particularly easy-to-manufacture battery module is achieved when the terminal contacts of the individual cells penetrate the respective slots of the cell connectors, are approximately orthogonally routed, and are electrically conductive and mechanically secure on the surface of the cell connectors facing away from the individual cells. This achieves a particularly simple and secure electrical and mechanical connection within the battery module.

[0010] A further increase in electrical safety is achieved if, in the case of a slot in a cell connector adjacent to a web of the carrier plate, the pole contacts are relocated away from the web. This minimizes the electrically effective height of the cell connector in the area of ​​the web, i.e., adjacent to the next cell connector.

[0011] In a particularly preferred embodiment of the invention, the respective pole contacts of the individual cells are formed at two opposite ends, with two carrier plates being provided such that the respective pole contacts at the opposite ends of the individual cells are electrically conductively and mechanically firmly connected to first cell connectors with the first polarity and to second cell connectors with the second polarity. In other words, for individual cells with opposing pole contacts, e.g., positive poles on the left and negative poles on the right of the individual cells, two approximately identical carrier plates can be used.

[0012] First and second, essentially plate-shaped, cell connectors rest directly on each of the two carrier plates. The individual cells are arranged in groups such that, within such a group, the pole contacts with the same polarity point in the same direction. For example, in a first group, a first number of individual cells are arranged such that the positive poles point toward the first carrier plate, and consequently the negative poles point toward the second carrier plate. Adjacent to this, in a second group, a second number of individual cells are arranged such that their positive poles point toward the second carrier plate, and consequently the negative poles point toward the first carrier plate.

[0013] This arrangement provides a surprisingly simple way to connect specially designed individual cells, namely flat cells or pouch cells with flag-like pole contacts at two opposite ends. Simply by using two carrier plates configured according to the invention, on which the first and second cell connectors rest directly, an electrically conductive and mechanically strong connection is achieved, which is also particularly secure.

[0014] In other words, the use of a first and second carrier plate, each with first and second cell connectors, is sufficient to produce a battery module from the specially designed individual cells. Depending on the design of the first and second cell connectors, and taking into account the values ​​of the individual cells, battery modules with a desired voltage and current can be realized. For example, two groups of three individual cells each, whose positive and negative poles are connected by first and second cell connectors, respectively, resting directly on the two carrier plates, result in a battery module with three times the current and the same voltage as the individual cells.

[0015] A particularly stable battery module is achieved when the carrier plate or each carrier plate is manufactured in one piece with molded-on plastic webs. The use of polypropylene or polyethylene, in particular, results in a strong and highly elastic, yet non-brittle, carrier plate. It was found that a thickness of two to three millimeters for the carrier plate or each carrier plate and a width of three to five millimeters for the web(s) is sufficient.

[0016] Safety is further enhanced if the or each carrier plate has a surrounding frame made of an electrically non-conductive material with a width of three to five millimeters around its outer edge. This frame, preferably seamless and integral with the or each carrier plate, prevents the lateral penetration of foreign metal objects in the event of a collision between the motor vehicle and the battery module.

[0017] It is advantageously proposed that a cover made of an electrically non-conductive material be provided, which rests on the frame and / or on the webs. This increases security against the cell connectors slipping over the webs in the event of an accident between the motor vehicle and the battery module. The cover can be manufactured relatively thin and light, preferably only five millimeters thick, since it only has to prevent electrical contact between the cell connectors and does not have to absorb or transmit any forces. The cover is preferably connected to the top of the frame or the webs in a force-fitting or form-fitting manner, e.g. by welding.

[0018] The invention will now be described in more detail with reference to a drawing. Fig. 1 a part of a battery module, Fig. 2 schematically shows a section through part of a first embodiment, Fig. 3 schematically shows a section through part of a second embodiment.

[0019] Fig. 1 shows part of a battery module 1 comprising a plurality of individual cells 2a, 2b. The individual cells 2a, 2b are designed as flat or pouch cells, with the respective pole contacts located at two opposite ends of the individual cells 2a, 2b. The individual cells 2a, 2b are arranged in groups next to one another, for example, within a protective housing (not shown). The individual cells 2a, 2b are cooled, for example, by a cooling plate (not shown), which is positioned beneath the individual cells 2a, 2b and supports them from below.

[0020] In the present case, it can be seen that on the left and right side of the battery module 1, a group of four individual cells 2a is arranged in such a way that their pole contacts 3 with first polarity, e.g. positive pole 3, point forwards, while in between a further group of four individual cells 2b is arranged in such a way that their pole contacts 4 with second polarity, e.g. negative pole 4, point forwards.

[0021] Since in Fig. 1 only shows one half of the battery module 1, this is due to the fact that the pole contacts 4 with second polarity, e.g. negative pole 4, of the groups of four individual cells 2b arranged on the left and right sides of the battery module 1 each point to the rear, and the pole contacts 3 with first polarity, e.g. positive pole 3, of the further group of four individual cells 2a arranged in between point to the rear. This is not in each case Fig. 1 shown.

[0022] At the respective ends of the battery module 1 support plates 5 are arranged, of which only the front one is Fig. 1. The carrier plates 5 are made of plastic, e.g. polypropylene or polyethylene.

[0023] Electrical cell connectors 6.1, 6.2, which are essentially plate-shaped, rest directly on the carrier plate 5. The electrical cell connectors 6.1, 6.2 are made of a highly electrically conductive material, e.g., copper. In this case, the electrical cell connectors 6.1, 6.2 are screwed to the carrier plate 5.

[0024] The electrical cell connectors 6.1, 6.2 serve to electrically connect several pole contacts 3, 4 of the same polarity of several individual cells 2a, 2b and to mechanically secure the individual cells 2a, 2b. In the present case, it can be seen that a first cell connector 6.1 contacts four pole contacts 3 of four individual cells 2a with a first polarity, e.g., positive pole 3. A second cell connector 6.2, in contrast, contacts four pole contacts 4 of four further individual cells 2b with a second polarity, e.g., negative pole 4.

[0025] For this purpose, the cell connectors 6.1, 6.2 each have slots 11 for the penetration of the respective pole contacts 3, 4 of the individual cells 2a, 2b. Since the pole contacts 3, 4 are each flag-like, i.e. flat and elongated, penetration of the respective slots 11 of the cell connectors 6.1, 6.2 and the carrier plates 5 is easily achieved for the respective pole contacts 3, 4 of the individual cells 2a, 2b. An approximately orthogonal relocation of the respective pole contacts 3, 4 of the individual cells 2a, 2b and an electrically conductive and mechanically strong fixation on the surface of the cell connectors 6.1, 6.2, for example by soldering, results in a good electrically conductive and mechanically strong connection.

[0026] The battery module 1 shown is suitable for different embodiments of an inventive design.

[0027] In Fig. 2 and Fig. 3 schematically shows sections through a carrier plate 5 according to two different embodiments of the invention.

[0028] In a first embodiment according to Fig. 2, two cell connectors 6.1 and 6.2 rest directly on a carrier plate 5. The cell connectors 6.1 and 6.2 each connect pole contacts 3, 4 of different individual cells 2a, 2b. Here, the cell connector 6.1 connects three pole contacts 3 of three individual cells 2a, each with a first polarity, e.g., positive pole 3. The cell connector 6.2 connects three pole contacts 4 of three other individual cells 2b with a different polarity, e.g., negative pole 4.

[0029] In addition, a continuous frame 8 with a width of three to five millimeters is provided on the outer edge of the carrier plate 5. The carrier plate 5 has a thickness of two to three millimeters. The webs 7 have a width of three to five millimeters.

[0030] The support plate 5 is made of plastic in one piece with the molded webs 7 and frame 8.

[0031] According to the invention, in the event of a crash of the motor vehicle with the battery module 1, a dangerous short circuit between the cell connectors 6.1 and 6.2 is prevented if the carrier plate 5 is deformed. This is because if, for example, the cell connector 6.1 is pushed toward the cell connector 6.2 due to a deformation of the carrier plate 5, the web 7 reliably prevents electrical contact between the two cell connectors 6.1, 6.2.

[0032] According to Fig. 3, a cover made of an electrically non-conductive material is additionally provided, which rests on the frame and / or on the webs 7. This prevents the connectors 6.1 or 6.2 from slipping over the web 7 in the event of a crash of the motor vehicle with the battery module 1.

Claims

[1] Battery module (1) with a plurality of electrically interconnected individual cells (2a, 2b), wherein the individual cells (2a, 2b) each have pole contacts (3, 4) with a first and a second polarity, wherein the individual cells (2a, 2b) are connected to a carrier plate (5) in such a way that the respective pole contacts (3, 4) penetrate the carrier plate (5), wherein the pole contacts (3) with the first polarity of at least two individual cells (2a) are each electrically conductively and mechanically firmly connected to a first cell connector (6.1) and the pole contacts (4) with the second polarity of at least two further individual cells (2b) are each electrically conductively and mechanically firmly connected to a second cell connector (6.2), wherein the carrier plate (5) is made of an electrically non-conductive material on which the cell connectors (6.1, 6.2) lie directly, and the carrier plate (5) in the region between the first and the second Cell connectors (6.1, 6.2) has a web (7) which is configured such that, in the event of deformation of the carrier plate (5), electrical contact between the first and the second cell connector (6.1, 6.2) is prevented, . characterized by that the individual cells (2a, 2b) are designed as flat cells or pouch cells, each with flag-like pole contacts (3, 4), and the cell connectors (6.1, 6.2) are essentially plate-shaped, and that the cell connectors (6.1, 6.2) have slots (11) for the respective pole contacts (3, 4) of the individual cells (2a, 2b) to penetrate. [2] Battery module (1) according to claim 1, wherein for the respective pole contacts (3, 4) of the individual cells (2a, 2b) a penetration of the respective slots (11) of the cell connectors (6.1, 6.2), an approximately orthogonal laying and an electrically conductive and mechanically strong fixing on the surface of the cell connectors (6.1, 6.2) is provided. [3] Battery module (1) according to claim 2, wherein, in the event that a slot (11) of the cell connector (6.1, 6.2) is provided adjacent to a web (7) of the carrier plate (5), a folding in the direction away from the web (7) is provided for the respective pole contact (3, 4). [4] Battery module (1) according to one of the preceding claims, wherein the respective pole contacts (3, 4) are formed at two mutually opposite ends of the individual cells (2a, 2b), and wherein two carrier plates (5) are provided such that the respective pole contacts (3, 4) at the mutually opposite ends of the individual cells (2a, 2b) are electrically conductively and mechanically firmly connected with the first polarity to first cell connectors (6.1) and with the second polarity to second cell connectors (6.2). [5] Battery module (1) according to one of the preceding claims, wherein the or each carrier plate (5) is made in one piece with molded-on web (7) or webs (7) made of plastic. [6] Battery module (1) according to claim 5, wherein the or each carrier plate (5) has a thickness of two to three millimeters and the web (7) or webs (7) has a width of three to five millimeters. [7] Battery module (1) according to claim 6, wherein the or each carrier plate (5) has at its outer edge a circumferential frame (8) made of an electrically non-conductive material with a width of three to five millimeters. [8] Battery module (1) according to claim 7, wherein a cover made of an electrically non-conductive material is provided, which rests on the frame (8) and / or on the webs (7). [9] Battery module (1) according to claim 8, wherein the cover is connected in a force-fitting or form-fitting manner to the upper side of the frame (8) or the webs (7).

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