Cover for electrically coupling multiple storage cells of an electrical energy storage module

Abstract

Cover (1) for electrically coupling several storage cells (2) of an electrical energy storage module, with electrically conductive contact sockets (5; 15) embedded in an electrically insulating material (7) of the cover (1), tapering inwards on their inner sides, into which poles (4) of the memory cells (2) can be inserted in an electrically contacting manner; two terminals (13, 14), one of which forms a positive terminal and the other a negative terminal of the electrically coupled memory cells (2), and several conductor tracks (6; 16) for electrically coupling the memory cells (2), in particular for serially coupling the memory cells (2), in a predefined manner, wherein the conductor tracks (6; 16) are completely contained within the cover (1), wherein the cover (1) can be mounted on the storage cells in a non-destructive manner; and wherein the contact sockets (5; 15) are conically shaped on their inner sides.

Description

[0001] The invention relates to a cover for electrically coupling a plurality of storage cells of an electrical energy storage module, an electrical energy storage module with such a cover and a motor vehicle with such an energy storage module.

[0002] Currently, there are several options available for electrically connecting the individual storage cells of an electrical energy storage module. Typically, the terminals of the storage cells are connected in series using cell connectors. The cell connectors are welded to the terminals of the storage cells, and these connections cannot be removed without damaging them. However, if a storage cell fails, the entire energy storage module must be replaced, which is associated with high costs.

[0003] DE 10 2009 053 344 A1 discloses a battery cell connector. This connector has a first connecting part designed for connection to a battery terminal of a first battery and a second connecting part designed for connection to a battery terminal of a second battery. The first connecting part is formed from a first electrically conductive material on the side facing a battery terminal, and the second connecting part is formed from a second electrically conductive material on the side facing a battery terminal.

[0004] DE 10 2011 087 040 A1 relates to a cell contact arrangement for an energy storage module with multiple electrochemical storage cells. Each storage cell has two electrical connection terminals. Also shown is a carrier plate that can be placed on the energy storage module, several cell connectors inserted into or integrated into the carrier plate for contacting the connection terminals, a cable harness for contacting the cell connectors, and a separate cable harness carrier that can be placed on the carrier plate for accommodating the cable harness.

[0005] DE 20 2009 015 277 U1 relates to a battery comprising at least one handle and a locking device for fastening the battery to a battery holder.

[0006] US 6 346 011 B1 shows a battery connection plate consisting of busbars for connecting the batteries to each other and a wire protector containing terminals and their connecting wires in a predetermined arrangement to determine the voltage of the desired batteries. The busbars and wire protector are overmolded into a resin plate, with the busbars arranged according to the batteries and the terminals held in contact with the corresponding busbars.

[0007] US 2014 / 0 038 008 A1 describes a battery cell module comprising a plurality of battery cells arranged adjacent to one another, busbars used to connect external terminals of the plurality of battery cells, and separators provided between adjacent battery cells. Each battery cell comprises an electrode body, a housing that accommodates the electrode body, and external terminals provided outside the housing and electrically connected to the electrode body. The separator comprises a heat transfer section that performs heat transfer between the heat transfer section and the battery cell, and an insulator that electrically insulates between the heat transfer section and the battery cell.

[0008] US 2017 / 0077487 A1 describes interconnects for connecting a series of battery cells, assemblies comprising these interconnects, methods for forming such interconnects, and methods for forming such assemblies. An interconnect has a conductor having two sections electrically insulated from each other. One section includes two contacts for connecting to battery cells and a fuse that establishes an electrical connection between these two contacts. The interconnect also has an insulator that adheres to the conductor and mechanically supports the two sections of the conductor. The insulator has an opening such that the fuse overlaps this opening, and the opening does not interfere with the operation of the fuse.

[0009] US 5 017 441 A shows an improved power source with a container means suitable for accommodating a plurality of polygonal dry cell batteries, wherein connection means are capable of contacting their terminals regardless of their angular arrangement.

[0010] Another possibility of coupling storage cells by means of an attachable carrier plate is known, for example, from DE 10 2011 087 040 A1.

[0011] It is an object of the present invention to provide a cover for electrically coupling multiple storage cells of an electrical energy storage module, which provides easier handling. This object is achieved by a cover according to claim 1, an electrical energy storage module according to claim 9, and a motor vehicle according to claim 11. Advantageous developments of the invention are the subject of the dependent claims.

[0012] According to one embodiment of the invention, a cover for electrically coupling a plurality of storage cells of an electrical energy storage module is provided, comprising electrically conductive contact sockets embedded in an electrically insulating material of the cover, which contact sockets taper inwards on their inner sides (i.e. in the direction away from the storage cells), into which poles of the storage cells can be inserted in an electrically contacting manner; two connections, one of which forms a positive pole and the other a negative pole of the electrically coupled storage cells, and a plurality of conductor tracks for electrically coupling the storage cells, in particular for serially coupling the storage cells, in a predefined manner, wherein the conductor tracks are completely accommodated within the cover, wherein the cover can be detachably mounted on the storage cells in a non-destructive manner.The contact sockets are preferably accommodated in the cover in such a way that, of the outer sides of the contact sockets, at most the sides facing the memory cells are exposed. In this case, the contact sockets would not protrude beyond the outer side of the cover. However, it is also possible for the contact sockets to protrude slightly beyond the outer side of the cover; in particular, they protrude a maximum of 30% of the contact socket depth beyond the outer side. The contact socket depth is the depth inside the contact socket along the insertion direction of the poles of the memory cells. The conductor tracks are completely accommodated within the cover, which means that the conductor tracks are not exposed to the outside surrounding the cover. The advantage of this exemplary embodiment is that it creates a one-piece, compact cover that can be assembled by pressing on orThe cover is already secured to the terminals of the storage cells, as the tapered contact sockets secure the cover to a certain extent to the energy storage module when plugged onto the terminals. The non-destructively removable cover allows the cover to be removed to replace a single storage cell in the event of a fault and then reattached after the defective cell has been replaced.

[0013] Furthermore, the contact sockets are conical on their insides. This serves both as a guide during insertion and thus the alignment of the cover relative to the energy storage module. It also secures the cover to the energy storage module by pressing the terminals into the conical contact sockets, thereby holding them in place with friction.

[0014] According to a further embodiment of the invention, the cover has at least three layers, with a conductor layer embedded between two electrically insulating cover layers. The two cover layers thus form a contact protection layer, and the intermediate conductor layer can be adapted depending on the desired memory cell connection or coupling, so that various covers with different circuits, for example, covers for a serial electrical connection of the memory cells and covers for a parallel electrical connection of the memory cells, can be provided with relatively little effort.

[0015] According to a further embodiment of the invention, the cover has a cavity for liquid coolant or refrigerant. The advantage of this embodiment is that the waste heat from the energy storage module is dissipated at the top, in the area of ​​the poles and conductor tracks. In the prior art, energy storage modules are often cooled at the bottom, i.e., on the opposite side of the storage cells, but there is a greater cooling requirement on the pole side.

[0016] According to a further embodiment of the invention, the cavity is formed adjacent to the conductor tracks, but outside the conductor tracks.

[0017] According to a further embodiment of the invention, the cover has an inlet and an outlet opening into the cavity, via which the coolant or refrigerant can be supplied or discharged.

[0018] According to a further embodiment of the invention, the coolant is a phase change material, in particular a two-phase phase change material.

[0019] According to a further embodiment of the invention, the cavity for the coolant or refrigerant is provided by a tube which is coated in sections with electrically conductive material to form the conductor tracks or is composed of sections of electrically conductive material and electrically insulating material.

[0020] Furthermore, the invention provides an electrical energy storage module with a plurality of storage cells that are electrically coupled to a cover according to one of the preceding embodiments.

[0021] According to one embodiment of the energy storage module, the storage cells are lithium-ion batteries.

[0022] Furthermore, the invention provides a motor vehicle with such an electrical energy storage module.

[0023] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. These drawings show the following: Fig. 1 is a schematic three-dimensional representation of a cover according to the invention and a plurality of storage cells; Fig. 2 is a schematic detailed view of a contact socket and a section of a conductor track in the cover of Fig. 1; Fig. 3 is a schematic representation of a further development of the cover from Fig. 1, with a coolant or refrigerant flow adjacent to the conductor tracks, and Fig. 4 is a schematic representation of a further development of the cover from Fig. 1, with a coolant or refrigerant flow in the conductor tracks.

[0024] Fig. 1 is a schematic three-dimensional representation of a cover 1 according to the invention and a plurality of storage cells 2 (only some are provided with a reference numeral). Fig. 2 is a schematic detailed view of a contact socket and a section of a conductor track in the cover of Fig. 1. The storage cells 2 are preferably prismatic, rechargeable lithium-ion batteries. The plurality of storage cells 2 are preferably electrically connected to one another in series, but a parallel connection would also be conceivable depending on the application. This plurality of storage cells 2, which are electrically coupled to one another and assigned to a single cover 1, together with the cover 1 form an electrical energy storage module 3. In motor vehicles, several such energy storage modules 3 are usually electrically connected to one another in parallel and form an electrical energy storage device that provides the energy at least for the propulsion of the motor vehicle. The storage cells 2 each have two poles 4, more precisely an anode and a cathode terminal, which are arranged on the same side of the storage cell 2.The poles 4 (only some are provided with a reference number) protrude from the storage cell 2 and taper their outer circumference in the direction away from the storage cell 2. In particular, the poles 4 taper a diameter of their circular cross-section in the direction away from the storage cell 2. Preferably, the poles 4 are conical or conical or truncated cone-shaped.

[0025] The cover 1 is preferably prismatic and has contact sockets 5 embedded in the cover 1 (only some are provided with reference numerals), into which the poles 4 of the storage cells can be inserted. The inside of a contact socket 5 is adapted to the outside of the pole 4 assigned to this contact socket, i.e. they have a substantially identical shape, so that the insides of the contact sockets 5 fit as well as possible against the outsides of the poles 4 in order to establish good electrical contact. The contact sockets 5 of an energy storage module 3 are connected to one another by means of conductor tracks 6 such that the desired coupling of the storage cells 2, for example an electrical series or parallel connection, is realized. For example, as in Fig. 1, an anode terminal of a storage cell 2 can be connected to a cathode terminal of an adjacent storage cell 2 by electrically connecting the contact sockets 4 in contact with these terminals by means of a conductor track 6. The conductor tracks 6, in particular the ends of the conductor tracks 6, are connected to the contact sockets 5 in an electrically conductive manner, in particular in a non-destructively detachable manner. For example, the conductor tracks 6 can be welded or soldered to the contact sockets 5. However, it is also possible for the contact sockets 5, for example two, to be each formed integrally with a conductor track 6. The conductor tracks 6 and the contact sockets 4 are embedded in an electrically insulating material 7 of the cover 1. The conductor tracks 6 are preferably not exposed to the outside (i.e. to the environment surrounding the cover 1) at any point.The contact sockets 5 are at least predominantly embedded in the cover 1, wherein the contact sockets 5 are preferably received in the cover 1 in such a way that, of the outer sides of the contact sockets, at most the sides 8 facing the storage cells 2 are exposed. In this case, the contact sockets would not protrude beyond the outer side of the cover. However, it is also possible for the contact sockets to protrude beyond the outer side of the cover, in particular they protrude a maximum of 30% of the contact socket depth beyond the outer side. The contact socket depth is the depth inside the contact socket 5 along the insertion direction of the poles 4 of the storage cells 2. The contact sockets 5 are tapered on their inner side in the direction away from the storage cell 2 along an insertion direction of the poles 4.In particular, the contact sockets 5 taper a diameter of their circular cross-section (perpendicular to the insertion direction) on their inner side in the direction away from the storage cell 2. The contact sockets 5 are preferably conical or truncated cone-shaped. The cover 1 can, but does not necessarily have to, be detachably connected to the rest of the energy storage module (not shown) or to a frame (not shown) holding the energy storage modules by means of screw connections 9. The cover 1 can be made of rigid materials. Likewise, the cover 1 can be made of flexible materials so that it is bendable. The latter would facilitate plugging the contact sockets 5 onto the poles 4 and thus the application of the cover 1 to the storage cells 2 and ensure a better frictional hold.

[0026] Various implementations of this inventive concept are conceivable. For example, the electrically insulating material 7 can be cast as a casting compound around the contact sockets 5 and conductor tracks 6. Furthermore, the electrically insulating material 7 can be designed in the form of two plates, one plate facing the memory cells 2 and one plate facing away from the memory cells 2, between which the conductor tracks 6 are formed in the form of a third layer. The plates could be rigid or flexible plates. The conductor track layer could be countersunk in one of the two or both plates made of electrically insulating material. The conductor tracks 6 can be designed as a plurality of individual, separate, rod-shaped, flat conductor tracks, in particular made of metal. It is also conceivable for the conductor tracks to be designed in the form of metallic conductor tracks on a circuit board or printed circuit board.The conductor tracks 6 can also be implemented in the form of a plug-in system, so that the wiring of the contact sockets 5 can be changed. In this case, plug-in options could be provided in one of the two or both plates made of electrically insulating material, into which plug-in options the conductor tracks 6 can be plugged depending on the desired wiring during the manufacture of the cover 1, so that covers with different wiring of the contact sockets 5 can be provided with relatively little effort. The cover 1 has a total of two connections 13 and 14, one of which forms a positive pole and the other a negative pole of the electrically coupled storage cells 2. This means that in the case of storage cells 2 connected in series by means of the cover 1, connection 13 would be the positive pole of this series connection and connection 14 would be the negative pole of this series connection.

[0027] Fig. 3 is a schematic representation of a further development of the cover 1 from Fig. 1, with a cooling or refrigerant flow adjacent to the conductor tracks. According to a further development, the cover 1 can be provided with an integrated cooling system. As shown in Fig. 3, a cavity 9 is provided adjacent to the conductor tracks 6, which are provided between the contact sockets 5. In the embodiment in Fig. 3, the contact sockets 5 and the conductor tracks 6 connecting them are formed in one piece, in particular monolithically. The cavity 9 is adapted to accommodate a cooling medium, wherein the cooling medium can directly contact the contact sockets 5 and the conductor tracks 6, or an electrically insulating coating, for example Teflon or a polymer coating, is formed between them. If the cooling medium directly contacts the contact sockets 5 and the conductor tracks 6, the cooling medium must be an electrically non-conductive cooling medium, for example, a non-electrically conductive oil. The cooling medium is preferably a liquid coolant or refrigerant.

[0028] The cavity 9 can also be a liquid-tight space filled with a phase-change material as the cooling medium. Preferably, however, the cavity 9 is provided with an inlet 10 and an outlet 11 and, apart from these inlets and outlets, is sealed liquid-tight. By means of the inlets and outlets 10, 11, the cavity 9 is integrated into a closed cooling or refrigeration circuit.

[0029] Fig. 4 is a schematic representation of a further development of the cover from Fig. 1, with a coolant or refrigerant flow in the conductor tracks. In the embodiment shown in Fig.4, the cavity 9, which is adapted to receive the cooling medium, is formed by the interior of a tube 12 which extends continuously from the inlet 10 to the outlet 11. In the tube 12, the contact sockets 15 are formed by indentations in the tube 12 in a shape as described in connection with the contact sockets 5. To form the conductor tracks 16 or to produce the electrical conductivity of the conductor tracks 16, which connect selected contact sockets 15 to one another, as well as to form the electrical conductivity of the contact sockets 15, the sections of the tube 12 which form the conductor tracks 16 and the contact sockets 15 are made of electrically conductive material and the remaining sections of the tube 12 are made of electrically insulating material.However, the tube 12 could also be made entirely of electrically insulating material and covered or coated in sections with an electrically conductive material to ensure electrical conductivity of the conductor tracks 16 and the contact sockets 15.

[0030] While the invention has been illustrated and described in detail in the drawings and the foregoing description, this illustration and description is to be understood as illustrative or exemplary rather than restrictive, and it is not intended to limit the invention to the disclosed embodiments. The mere fact that certain features are recited in various dependent claims is not intended to suggest that a combination of these features could not also be used to advantage.

Claims

[1] Cover (1) for electrically coupling several storage cells (2) of an electrical energy storage module, with electrically conductive contact sockets (5; 15) embedded in an electrically insulating material (7) of the cover (1) and tapering inwards on their inner sides, into which poles (4) of the storage cells (2) can be inserted in an electrically contacting manner; two terminals (13, 14), one of which forms a positive pole and the other a negative pole of the electrically coupled storage cells (2), and a plurality of conductor tracks (6; 16) for electrically coupling the memory cells (2), in particular for serially coupling the memory cells (2), in a predefined manner, wherein the conductor tracks (6; 16) are completely accommodated within the cover (1), wherein the cover (1) can be mounted on the storage cells in a non-destructive manner; and wherein the contact sockets (5; 15) are conical on their inner sides. [2] Cover (1) according to one of the preceding claims, wherein the cover (1) is constructed in at least three layers, wherein a conductor track layer is embedded between two electrically insulating cover layers. [3] Cover (1) according to one of the preceding claims, wherein the cover (1) has a cavity (9) for liquid coolant or refrigerant. [4] Cover (1) according to claim 3, wherein the cavity (9) is formed adjacent to the conductor tracks (6), but outside the conductor tracks (6). [5] Cover (1) according to one of claims 3 or 4, wherein the cover (1) has an inlet and outlet (10, 11) opening into the cavity (9), via which cooling or refrigerant can be supplied or discharged. [6] Cover (1) according to one of claims 3 or 4, wherein the coolant is a phase change material. [7] Cover (1) according to claim 3, wherein the cavity (9) for the cooling or refrigerant is provided by a tube (12) which is coated in sections with electrically conductive material to form the conductor tracks (16) or is composed of sections of electrically conductive material and electrically insulating material. [8] Electrical energy storage module with a plurality of storage cells (2) which are electrically coupled to a cover (1) according to one of claims 1 to 8. [9] Electrical energy storage module according to claim 8, wherein the storage cells (2) are lithium-ion batteries. [10] Motor vehicle with an electrical energy storage module according to claim 8 or 9.

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