Energy storage system of a motor vehicle

Abstract

Energy storage device (8) of a motor vehicle (2), comprising two battery modules (14), each having two poles (20) and each having a straight guide hole (22), and comprising a push rod (28) which is arranged to be transversely displaceable in the two guide holes (22), and which has an electrically conductive section (34), wherein by means of the electrically conductive section (34) one of the poles (20) of one battery module (14) can be electrically contacted with one of the poles (20) of the other battery module (14) by means of the electrically conductive section (34) by means of displacing the push rod (28), wherein the push rod (28) has a number of individual segments (52) corresponding to the number of battery modules (14), wherein each battery module (14) is assigned one of the segments (52).

Description

[0001] The invention relates to an energy storage device for a motor vehicle and a method for manufacturing an energy storage device.

[0002] Motor vehicles, such as passenger cars, have a primary drive system for propulsion, which increasingly includes an electric motor. In this case, for example, only one or more electric motors are used to propel the vehicle, making it an electric vehicle. Alternatively, the vehicle may also include an internal combustion engine.

[0003] An energy storage system is typically used to power the electric motor. The energy storage system itself consists of several battery modules, which are usually identical in construction. Each battery module, in turn, contains several individual battery cells, some of which are connected in series and some in parallel. Thus, each battery module provides a DC voltage, which is either a single or multiple of the voltage of one of the battery cells. The individual battery modules are electrically interconnected to form the energy storage system for the respective vehicle. For example, the individual battery modules are connected partly in parallel and partly in series, so that the energy storage system provides the desired DC voltage, with the energy storage system having a specific capacity.This allows for a modular design of the battery modules, enabling their use in different vehicle types and thus allowing for large-scale production, which reduces manufacturing costs. Only the wiring of the battery modules needs to be adapted to the specific vehicle type.

[0004] To connect the battery modules, the terminals are typically made using screw terminals or connectors. Each screw terminal has a cable with a cable lug at each end. Each cable lug is then placed on a corresponding terminal of a different battery module and secured with a nut or bolt. Alternatively, the individual terminals of the battery modules can be welded together, or the terminals can be designed as manually connectable plug connectors.

[0005] The aforementioned connection types each require a relatively large number of individual work steps, which increases manufacturing time. Furthermore, some of these steps must be performed manually. Because the wiring involves comparatively high electrical voltages, the risk to the person performing the work cannot be ruled out. Therefore, appropriate training is required, which further increases manufacturing costs.

[0006] A battery module is known from CN 206098528 U. The battery module has a battery terminal to which an external terminal is attached. The two terminals are in contact with each other via an electrically conductive section of a rod. When a force is applied, the rod is displaced between the two terminals, so that they are connected by means of another part of the rod, which is electrically insulating.

[0007] In US 2014 / 0363720A1 a housing for several energy cells is described, and in JP 2013-145757 A a battery with one pole to which a busbar is screwed is disclosed.

[0008] DE 10 2020 200 005 A1 shows a battery module for a traction battery in whose module housing two cell packs are arranged one behind the other in a longitudinal direction of the module, wherein the electrical poles of the cell packs are arranged between the two cell packs with respect to the longitudinal direction of the module.

[0009] From JP 2014 - 171 366 A, a high-voltage energy storage device is known. The connection of a positive electrode and a negative electrode between adjacent accumulator modules arranged in series is established by axially displacing the conductive section of a rod, which has alternating conductive and insulating parts in the axial direction.

[0010] The invention is based on the objective of providing a particularly suitable energy storage device for a motor vehicle and a particularly suitable method for manufacturing an energy storage device, advantageously simplifying assembly and / or increasing safety.

[0011] With regard to the energy storage device, this problem is solved according to the invention by the features of claim 1, and with regard to the method by the features of claim 9. Advantageous further developments and embodiments are the subject of the respective dependent claims.

[0012] The energy storage device is a component of a motor vehicle. The motor vehicle is preferably land-based and preferably has a number of wheels, at least one, preferably several or all, of which are driven by a drive system. Adequately, one, preferably several, of the wheels is designed to be steerable. This makes it possible to move the motor vehicle independently of a specific roadway, such as rails or the like. It is advantageously possible to position the motor vehicle essentially arbitrarily on a roadway, which is made, in particular, of asphalt, tar, or concrete. The motor vehicle is, for example, a commercial vehicle such as a truck or a bus. However, it is particularly preferred that the motor vehicle be a passenger car.

[0013] The motor vehicle has, in particular, a drive system by means of which the motor vehicle is propelled. For example, the drive system, especially the main drive system, is at least partially electric, and the motor vehicle is, for example, an electric vehicle. The electric motor is expediently operated by means of the energy storage device. The energy storage device is suitable for this purpose, and in particular is provided and configured accordingly. Preferably, an electrical converter is arranged between the energy storage device and the electric motor, by means of which the current supplied to the electric motor is regulated. Alternatively, the drive system additionally includes an internal combustion engine, so that the motor vehicle is configured as a hybrid vehicle.

[0014] The energy storage device expediently provides a direct current voltage, wherein the voltage is, for example, between 12 V and 80 V or between 200 V and 800 V, and, for example, essentially 400 V. Preferably, the energy storage device is a high-voltage battery.

[0015] The energy storage device comprises two battery modules, i.e., exactly two or more than two. Each battery module has two (electrical) poles, between which, during operation, a direct current (DC) voltage is applied. The battery modules thus each constitute an energy storage unit, and the two poles of each battery module represent, in particular, electrical poles, one of which is assigned a negative electrical potential and the other a positive electrical potential. The DC voltage is advantageously between 12 V and 80 V, and, for example, between 24 V and 60 V. In particular, the electrical voltage is essentially 30 V, 40 V, 50 V, or 60 V, with, for example, a deviation of 10%, 5%, or 0%.

[0016] Each battery module advantageously comprises one or more battery cells electrically connected between the two poles. The battery cells are connected, for example, in parallel and / or in series, so that the (electrical) voltage supplied at the two poles is generated by the battery cells. Each battery module advantageously has a housing within which the battery cells are arranged. Preferably, the two battery modules are mechanically fastened to one another in the assembled state, preferably their housings. In other words, the two battery modules are directly mechanically connected. Alternatively, they are spaced apart from each other to allow expansion during the charging / discharging process without the development of excessive mechanical stresses.

[0017] Furthermore, each battery module has a straight guide hole, which is expediently designed in the form of a channel. The cross-section of the guide hole is particularly round or, for example, rectangular or square. For example, the respective guide hole is open laterally, so that it is slotted, particularly along its longitudinal direction. However, it is particularly preferred that the guide hole is circumferentially closed and thus projects through an area spaced away from an edge of the battery module. In particular, the guide hole is at least partially formed by the housing, if any. The guide holes of the two battery modules are in particular arranged parallel to each other and are aligned with each other.

[0018] A push rod is arranged within the guide holes, allowing for transverse movement within the two guide holes. In particular, the push rod is at least partially supported by the guide holes. A clearance fit or, in some cases, an interference fit is implemented between the guide holes and the push rod. In summary, the push rod is guided by the guide holes. This design allows the push rod to be removed from the guide holes for disassembly of the energy storage device.

[0019] The push rod has an electrically conductive section, which is made, for example, of a metal. Preferably, the electrically conductive section is made of copper, such as pure copper or a copper alloy, silver, or gold. Particularly preferably, the electrically conductive section is made of nickel-plated copper or has a tin coating. This prevents oxidation.

[0020] The electrically conductive section is, for example, cylindrical or, more preferably, hollow cylindrical. This reduces the amount of material required. Adequately, the electrically conductive section is mounted on another section of the push rod, thus stabilizing it. Advantageously, the electrically conductive section forms the circumferential side of at least part of the push rod, preferably covering the entire circumference so that it is closed.

[0021] The electrically conductive section allows one pole of one battery module to be electrically connected to one pole of the other battery module. This requires sliding the push rod within the guide holes. In other words, sliding the push rod establishes or breaks the electrical contact between the two poles, thus electrically isolating them from each other. For example, depending on the battery module configuration, the two poles electrically connected by this section can have the same or different electrical polarities.

[0022] In the assembled state, the two poles are electrically contacted by means of the electrically conductive section. Specifically, this involves at least partial direct mechanical contact of the electrically conductive section with one of the poles or with a component electrically contacted by it. By moving the push rod within the guide holes, this direct mechanical contact can be broken, thereby also terminating the electrical contact.

[0023] In this energy storage device, creating the electrical contact requires only a transverse movement of the push rod, which conveniently has only a single degree of freedom: transverse displacement. This simplifies assembly. The number of required work steps is also reduced, thus shortening manufacturing time. Furthermore, no specialized expertise is required, allowing assembly to be carried out by untrained personnel. Additionally, at least some of the energy storage device's electrically potential components are surrounded or located within the guide holes, preventing accidental contact. Consequently, safety is increased.

[0024] In one variant, the sub-rod has a guide tip or at least a chamfer, thus simplifying assembly even with battery modules that are at least partially spaced apart. Alternatively, the battery modules are widened in the area of ​​the guide holes. These designs take into account that a change in the volume of the battery modules, or at least a change in their geometry, can occur during charging / discharging. These measures prevent mechanical stress. Alternatively, the battery modules are made relatively rigid in the area of ​​the guide holes, preferably the entire housing, so that the push rod is not subjected to stress during operation.

[0025] For example, the electrical contact allows the voltage supplied by the battery modules to be adjusted to the desired voltage of the energy storage system. For this purpose, the battery modules are conveniently connected in series using a pushrod. Alternatively, the pushrod can be used to connect the two battery modules in parallel, thus increasing the energy storage capacity. For instance, one of the battery modules is permanently installed in the vehicle or at least permanently assigned to it. The other battery module is then installed as needed and connected to the existing one, thereby increasing the vehicle's range.The additional battery module is rented for a specific period, allowing the vehicle's range to be temporarily increased without requiring it to be equipped with two costly battery modules from the outset. Each battery module consists primarily of a high-voltage battery.

[0026] Alternatively, both battery modules, or preferably all of them, are arranged in a housing of the energy storage system. A battery management system is preferably arranged in the housing of the energy storage system, by means of which the charging or discharging of the battery modules is regulated and / or controlled. This increases the service life of the battery modules.

[0027] For example, the electrically conductive section is directly electrically contacted with one of the poles of one of the battery modules. Specifically, a conductor, such as a cable, is used for this purpose. This allows the push rod to continue sliding within the guide holes. The cable is conveniently soldered or welded to the electrically conductive section. In particular, the guide hole of the other battery module has an area lined with an electrical contact. By sliding the push rod, the section is made into contact with this electrical contact.

[0028] Preferably, each guide hole is lined with an electrical contact. This electrical contact is, for example, strip-shaped or, more preferably, hollow cylindrical, such as a ring, thus forming a contact ring. The electrical contact is advantageously made of a metal such as copper, silver, or gold. More preferably, the electrical contact is made of nickel-plated copper or has a tin coating. Suitablely, the electrical contact is made of the same material as the electrically conductive section of the push rod. Each electrical contact is electrically connected to one of the poles of the respective battery module. This connection is preferably rigid, and the electrical contact is, for example, welded to the respective pole.By moving the push rod, the electrically conductive section is moved over the electrical contacts so that it preferably rests directly against the two electrical contacts, thus establishing electrical contact between them via the conductive section. Alternatively, for example, the electrically conductive section is rigidly connected to one of the poles, and the pole of the other battery module is connected, or can be connected, to the electrically conductive section by means of a corresponding electrical contact.

[0029] In a further development, the electrically conductive section is mechanically connected to the electrical contact(s). For example, the electrical contact has an internal thread, and the electrically conductive section has at least a partial external thread, allowing the electrically conductive section to be screwed into the respective electrical contact. This prevents unintentional removal or movement of the push rod. Alternatively, the electrical contact is designed like a bayonet and rotatably mounted in the respective guide hole. When the push rod is inserted transversely, the electrical contact is partially rotated, and elements on the electrical section and the electrical contact engage with each other. These elements then lock together, preventing unintentional removal.To release the locking mechanism, for example for disassembly, it is advantageous to use a suitable device to release the locking. Alternatively, the electrical contact can be spring-loaded, so that there is contact pressure between the respective electrical contact and the electrically conductive section. This reduces the contact resistance between the two. Alternatively, or in combination with this, an electrically conductive paste, such as copper paste, can be applied between them, further reducing the electrical contact resistance. Another alternative is to clamp the electrically conductive section using the respective electrical contact, thus creating a frictional connection between them.Alternatively or in combination with this, the electrically conductive section and / or the respective electrical contact is deformed, for example elastically and / or plastically, when electrical contact is made. This increases stability. In particular, the push rod is designed as a hollow rod, which is moved transversely in the guide holes so that electrical contact is made. For example, due to appropriate dimensions, the electrically conductive section is pressed into the interior of the push rod. Subsequently, another rod is inserted into the hollow push rod, by means of which the electrically conductive section is pressed radially outwards against the electrical contact. Alternatively, forces directed towards each other are applied to both ends of the push rod to deform it.

[0030] Preferably, the energy storage system comprises more than two battery modules. Ideally, the battery modules are identical in construction, resulting in a modular energy storage system. This allows the energy storage system to be adapted to different requirements by using identical components, thus reducing manufacturing costs. For example, the energy storage system may have only a single battery management system that regulates / controls all battery modules. The number of battery modules is preferably between 3 and 50, and ideally between 5 and 30.

[0031] At a minimum, each battery module has two poles and a straight guide hole. The push rod extends through all guide holes, and at least two battery modules are electrically connected to each other via the push rod. Ideally, all battery modules are electrically connected to each other via the push rod. This allows for electrical contact to be made by sliding the push rod transversely, thus simplifying manufacturing.

[0032] For example, one of the poles of each battery module is electrically contacted by the same electrically conductive section of the push rod. All battery modules are connected in parallel. For instance, the push rod consists of only this single electrically conductive section. This simplifies manufacturing. Each battery module conveniently has an additional guide hole within which another push rod is mounted for transverse movement. The two push rods are advantageously identical in construction. The remaining electrical pole of each battery module is assigned to this additional guide hole, so that the remaining poles of the battery modules are electrically contacted by means of this additional push rod. This simplifies the complete wiring of the energy storage system.For example, the two push rods are assigned to different ends of each battery module, or alternatively to the same side.

[0033] Alternatively, each guide hole is assigned a second electrical contact, which lines a second area of ​​the same guide hole. This second electrical contact is electrically connected to the remaining pole of the respective battery module. Thus, each guide hole has two electrical contacts, each connected to different poles of the respective battery module. The push rod has several electrically conductive sections that are electrically insulated from each other. Between these electrically conductive sections, there is another section, preferably made of plastic. Specifically, the electrically conductive sections alternate with the non-conductive sections in the transverse direction of the push rod.For example, the number of electrically conductive sections is equal to two or corresponds to the number of battery modules, and in particular is equal to the number of battery modules or reduced by one.

[0034] Each electrically conductive section of the push rod is contacted by two electrical contacts. Advantageously, the electrical contacts of each conductive section are assigned to different battery modules. This makes it possible to connect all battery modules in series using a single push rod. In this case, the electrical section is advantageously continuous. Alternatively, each electrically conductive section has several subsections connected by a suitable conductor. This makes it possible to connect all battery modules in parallel using a single push rod. Preferably, the second electrical contact and the electrical contact of each battery module are identical in design, which simplifies manufacturing.In particular, electrical contact is also made with the respective electrically conductive section of the push rod in the same way, thus simplifying assembly.

[0035] For example, the push rod has a base body made of plastic, onto which the electrically conductive sections are applied along its longitudinal direction. Preferably, the electrically conductive sections are each formed by means of a cylinder. These cylinders are, for example, hollow, and are suitably placed on the continuous base body of the push rod and / or, for example, at least partially overmolded with the same material as the base body. This increases its robustness.

[0036] The push rod has a number of individual segments corresponding to the number of battery modules. Each battery module is assigned one of the segments, which is expediently positioned in the respective guide hole. Preferably, each segment is assigned at least one of the electrically conductive sections. In particular, each segment extends to both ends of the respective guide hole, so that each guide hole is filled by the respective segment. The segments are initially separate from each other, and when the battery modules are joined together, the individual segments are also joined together to form the push rod. The individual segments may, for example, simply rest loosely against each other or be connected to one another. Preferably, when the battery modules are joined together, the individual segments are also fastened to one another. In particular, they are snapped together.

[0037] By means of a transverse movement of the push rod, each segment is at least partially inserted into the guide hole of the directly adjacent battery module, thus efficiently establishing electrical contact. Since the individual segments are in direct contact with one another, applying pressure to one of the outer segments causes all segments to be moved transversely, thereby establishing electrical contact. Only a relatively small movement of the push rod is required to create complete electrical contact. Consequently, damage to the individual components of the energy storage system due to the transverse movement of the push rod for electrical contact is avoided. The force required is also reduced.Furthermore, it is possible to disable the electrical contact by moving the push rod by the same amount in the opposite direction and, for example, to replace one of the battery modules.

[0038] For example, one of the battery modules has a connection by means of which the energy storage device is electrically connected to other components of the vehicle. Particularly preferably, however, the pushrod has a connection that is electrically connected to the electrically conductive section. The connection is, for example, integrally formed with the electrically conductive section or connected to it by means of an electrical conductor, which is, for example, embedded in the base body of the pushrod. Thus, it is possible to electrically connect the energy storage device by means of the electrical contact of the connection. Therefore, the battery modules can be designed to be identical in construction, and it is not necessary to equip all of them with a connection, a large proportion of which would not be used.Preferably, the connection is an integral part of one end of the push rod and expediently forms the end of the push rod. The connection itself has, for example, a threaded bolt or a flat section so that a cable can be welded to it.

[0039] For example, to establish an electrical connection, the push rod is moved transversely within the guide holes, either manually or using a tool. A force is applied directly to the push rod, parallel to the guide holes and acting directly on it. Advantageously, the energy storage device incorporates a lever that is operatively connected to the push rod. Actuating the lever moves the push rod transversely. This eliminates the need to touch the push rod for movement, and the lever provides electrical insulation. Consequently, safety is increased. Furthermore, the lever allows for the application of comparatively large forces.

[0040] The lever is advantageously mounted on one of the battery modules to increase robustness. Preferably, each battery module is assigned a corresponding lever, and the lever moves the portion of the push rod located in its respective guide hole transversely. During assembly, all levers are suitably connected to one another so that actuation of one lever moves all of them. In other words, the levers are coupled to each other. The levers ensure that the force is applied evenly to the push rod, preventing tilting or compression of any part of the push rod. Advantageously, the push rod is divided into individual segments, and each segment is operatively connected to the lever assigned to the same battery module.

[0041] The method serves to manufacture an energy storage device, which is particularly a component of a motor vehicle. The method provides for the supply of two or more battery modules, each having two poles and a straight guide hole. The two poles of each battery module are advantageously electrically contacted with at least one battery cell of the same battery module, so that an electrical potential difference exists between the two poles. Preferably, the two battery modules are fastened together, for which they advantageously have suitable fastening means, for example, snap-fit ​​elements. Alternatively, the fastening means are, for example, designed to be flexible, so that movement of the battery modules relative to each other is at least partially possible. In particular, after fastening, the two guide holes are arranged parallel to each other and aligned.In this configuration, the two battery modules are electrically isolated from each other. In other words, the two poles of each battery module are electrically insulated from the poles of the other battery module.

[0042] In a subsequent step, a push rod with an electrically conductive section is moved transversely within the guide holes. This movement brings the conductive section into electrical contact with one of the poles of each battery module. For example, the push rod is either fully inserted into the guide holes or moved only a fraction of the length of each hole, particularly if the push rod has multiple segments, each of which is already assigned to a specific battery module. The push rod is then assembled when the battery modules are joined together.

[0043] Furthermore, the invention relates to a motor vehicle with such an energy storage device.

[0044] The advantages and further training described in connection with the energy storage system can also be applied analogously to the manufacturing process / motor vehicle and to each other, and vice versa.

[0045] Exemplary embodiments of the invention are explained in more detail below with reference to a drawing. The drawing shows: Fig. 1. Schematically simplified, a motor vehicle that has an energy storage device. Fig. 2 a method for manufacturing the energy storage device, Fig. 3, Fig. 4 each section shows the energy storage device comprising several battery modules and a push rod during its manufacture at different stages of production, Fig. 5. Partially shown is a second embodiment of the energy storage device during its manufacture. Fig. 6. Partially shown is a third embodiment of the energy storage device during its manufacture. Fig. 7, Fig. 8 each shows a section of a fourth embodiment of the energy storage device during its manufacture at different stages of production, Fig. 9 a fifth embodiment of the energy storage device, and Fig. 10 an alternative embodiment of the battery modules.

[0046] Corresponding parts are marked with the same reference symbols in all figures.

[0047] In Fig. Figure 1 schematically simplifies the representation of a motor vehicle 2 in the form of a passenger car. The motor vehicle 2 has several wheels 4, at least two of which are driven by an electric motor 6. The electric motor 6 is powered by an energy storage device 8, which is a high-voltage battery. The energy storage device 8 provides a direct current voltage of 400 V or 800 V.

[0048] In Fig. Figure 2 shows a schematically simplified method 10 for manufacturing the energy storage device 8. In a first step, several battery modules 14 are provided, as shown in Fig. Figure 3 shows only two of the five battery modules 14, which are identical in construction and each have a cuboid housing 16. A plurality of battery cells 18, such as lithium-ion battery cells, are arranged within each housing 16. Between two poles 20 of each battery module 14, some of the battery cells 18 are connected electrically in parallel and some in series. Therefore, a DC voltage of 50 V is present between the two poles 20.

[0049] Furthermore, each battery module 14 has a guide hole 22 that is straight and extends through the entire housing 16. The cross-section of the guide hole 22 is round. Each of the guide holes 22 has two areas 24, each lined by an electrical contact 26. The two electrical contacts 26 of each battery module 14 are separated from each other and therefore not directly electrically connected. In summary, each of the guide holes 22 is lined in one of the areas 24 with one of the electrical contacts 26, and in the remaining area 24 with the remaining electrical contact 26.

[0050] Each of the two electrical contacts 26 of each battery module 14 is electrically contacted with one of the poles 20 of the respective battery module 14. Thus, the battery cells 18 of each battery module 14 are connected between the two electrical contacts 26. The electrical contacts 26 are formed by rings made of nickel-plated copper and define the boundary of the respective guide hole 22 in the respective area 24.

[0051] The two battery modules 14 are attached to one another. In this process, one side of the housing 16 is directly mechanically pressed against the adjacent housing and fixed in place. In one alternative configuration (not shown), the housings 16 have corresponding fastening elements for this purpose. In another alternative configuration, the modules are fastened using separate fasteners, such as screws or a strip spanning all battery modules 14. Regardless of the fastening method, the battery modules 14 are arranged such that the guide holes 22 are parallel and aligned with each other.

[0052] Furthermore, in the first work step 12, a push rod 28 is provided. The cross-section of the push rod 28 is also round and corresponds to the cross-section of the guide holes 22. The push rod 28 has a base body 30, which is made of a plastic and is essentially cylindrical. A total of five hollow cylindrical rings 32, which form contact rings and are made of nickel-plated copper, are mounted on the base body 30. The identical rings 32 each form an electrically conductive section 34 and are spaced apart from each other, so that, by means of the base body 30, a further section 36, which is electrically insulating, is formed between each of the electrically conductive sections 34.In other words, the electrically conductive sections 34 and the further sections 36 alternate along the extension of the push rod 28, with each of the electrically conductive sections 34 being formed by means of a cylinder, namely a hollow cylinder. Each of the electrically conductive sections 34, i.e., one of the rings 32, forms one of the ends 38 of the push rod 28 and is used as a connection 40. Thus, the connection 40 is integral with the respective electrically conductive section 34 and is therefore electrically contacted with it.

[0053] In a subsequent second work step 42, the push rod 28 is inserted into the guide holes 22, as shown in Fig. Figure 4 shows the length of the push rod 28, which is equal to the length of the joined guide holes 22. The push rod 28 is inserted into the guide holes 22 until both ends 38 are flush with the housing of the two outer battery modules 14 (not shown). When the push rod 28 is positioned in this way, the two electrically conductive sections 34 forming the terminals 40 are in direct mechanical contact with one of the electrical contacts 26 each and are thus electrically connected to it. The remaining three electrically conductive sections 34 in between are each in direct mechanical contact with two of the electrical contacts 26 and are consequently connected to them, with each of the two electrical contacts 26 being assigned to different battery modules 14.Thus, by means of one of the electrically conductive sections 34, two poles 20 of different battery modules 14 are electrically contacted with each other, and the battery modules 14 are electrically connected in series by means of the push rod 28. Therefore, five times the DC voltage provided by each of the battery modules 14 and present between the respective poles 20 is present between the two terminals 40. In summary, the electrical contact of the poles 20 of different battery modules 14 of the energy storage device 8 is achieved by sliding the push rod 28 in the guide holes 22.

[0054] When installed in the motor vehicle 2, a corresponding cable is welded to the two terminals 40. In one variant (not shown in detail), each terminal 40 has an external thread and protrudes at least partially beyond the assembly of the battery modules 14. This makes it possible to attach a cable lug there.

[0055] If the push rod 28 is moved in the opposite direction by an amount corresponding to the extension of half of the respective electrically conductive section 34 along the direction of extension of the push rod 28, the electrical contact between one of the parts of the electrically conductive sections 34 and one of the associated electrical contacts 26 is broken, so that the battery modules 14 are again electrically isolated from each other.

[0056] In one detailed embodiment, each of the electrical contacts 26 has a spring mechanism or is spring-loaded, so that it is pressed against its respective electrically conductive section 34, thus reducing contact resistance. A suitable conductive paste can also be used to further reduce this resistance. In another, not shown, alternative, the rings 32 are snapped into place with their respective electrical contacts 26, thereby increasing robustness and stability.

[0057] In Fig. Figure 5 shows an alternative embodiment of the energy storage device 8, in which the battery modules 14 remain unchanged and thus each again have the guide hole 22 with the two electrical contacts 26. The push rod 28, however, is modified and now has only two electrically conductive sections 34, each of which comprises five subsections 44 in an annular form. The extent of these subsections along the longitudinal direction of the push rod 28 is equal to the length of the electrical contacts 26 along the direction of extension of the guide hole 22. All subsections 44 of the same electrically conductive section 34 are connected to each other by means of a common conductor 46, which is embedded in the base body 30. Due to the conductors 46, all subsections 44 of the same electrically conductive section 34 are therefore at the same electrical potential.

[0058] When the push rod 28 is fully positioned in the guide holes 22 of the battery modules 14, the poles 20 are always electrically connected to each other with the same electrical polarity by means of the subsections 44, so that the battery modules 14 are connected in parallel by means of this push rod 28. The subsection 40, located at each end 38 of the push rod 28, forms the terminal 40 to which further components of the motor vehicle 2 can be electrically connected.

[0059] In Fig. Figure 6 shows a further alternative of the energy storage device 8 during assembly. Here, the battery modules 14 are modified, and in these, the guide hole 22 has only one of the electrical contacts 26. The remaining electrical contact 26 is part of another guide hole, which is identical in construction to the guide hole 22 of the respective battery module 14, but is located at a different end of the housing 16. In this example, the push rod 28 is made of a single material, namely nickel-plated copper, and is thus formed entirely by the electrically conductive section 34. A further push rod 50, identical in construction to the push rod 28, is also present and is inserted into the additional guide hole 48.Here, the additional push rod 50 electrically contacts all electrical contacts 26 of the additional guide holes 48, and the push rod 28 connects all electrical contacts 26 of the guide holes 22 to each other. In this example, each of the push rods 28, 50 is assigned electrical contacts 26 with the same electrical polarity. In summary, each of the poles 20 of each battery module 14 is electrically contacted by the same push rod 28, 50 and thus by the same electrically conductive section 34.

[0060] In Fig. 7 and Fig. Figure 8 shows an alternative embodiment of the energy storage device 8. The battery modules 14 essentially correspond to those shown in Fig. In the variant shown in Figure 3, each of the guide holes 22 again has the two electrical contacts 26. In contrast, a segment 52 of the push rod 28 is arranged in each of the guide holes 22. In other words, the push rod 28 is divided into several segments 52, which are initially separate from each other. Each of the segments 52 has one of the electrically conductive sections 34 and one of the other sections 36. Each of the electrically conductive sections 34 is already in direct mechanical contact with one of the electrical terminals 26 of the same battery module 14. In a variant not shown in detail, a locking mechanism is provided, preventing the removal of the segment 52 from its assigned guide hole 22. However, transverse movement of the segment 52 within the respective guide hole 22 is still possible.

[0061] Once the battery modules 14 are mechanically aligned, the individual segments 52 also abut each other. In one variant, not shown in detail, the individual segments 52 are fastened together, for example by means of adhesives or snap-fit ​​elements.

[0062] Following this, as in Fig. As shown in Figure 8, a force is exerted on the outer end of one of the outermost segments 52, parallel to the guide holes 22, in the direction of the remaining segments 52. This force is transmitted via this segment 52 to the adjacent segment 52 and successively to the remaining segments 52. As a result, all segments 52 are displaced in the same direction within the guide holes 22, with the electrically conductive sections 34, except for one of the outermost segments 52, penetrating the guide hole 22 of the respective adjacent battery module 14 and coming into direct mechanical contact with the electrical contact 26 located there.Thus, these electrically conductive sections 34 are mechanically directly connected to two of the electrical contacts 26, which are consequently electrically contacted with each other by means of this associated electrically conductive section 34, so that all battery modules 14 are electrically connected in series.

[0063] In Fig. Figure 9 shows a further development. In this version, each of the battery modules 14 has a lever 54 mounted on the respective housing 16. When the lever 54 is pivoted, the respective segment 52 is displaced transversely in the respective guide hole 22. In other words, each of the levers 54 is operatively connected to the respective segment 52 of the push rod 28. During assembly, after the battery modules 14 are fastened to one another, the free ends of the levers 54 are also coupled by means of a common operating rod 56, whereby the coupling in the example shown here is achieved by means of elongated holes. When the operating rod 56 is moved, all levers 54 are pivoted and therefore all segments 52 are also moved in the respective guide hole 22. Due to the elongated holes that serve for the coupling, this also occurs with only a transverse movement of the operating rod 56.Due to the levers 54, no direct mechanical contact between the individual segments 52 is required to move them, allowing for comparatively large manufacturing tolerances. This also ensures a uniform application of force to the push rod 28. When the operating rod 56 is moved in the opposite direction, the electrical contact between the battery modules 14 is broken, allowing it to be used, for example, to shut down the energy storage unit 8 in an emergency.

[0064] In Fig. 10 is a variation of the one in Fig.The battery module 14 is shown in Figure 7. In this case, the electrically conductive section 34 is directly contacted with one of the poles 20 of the battery module 14, in particular by means of a wire or cable. As a result, the guide hole 22 has only a single electrical contact 26, which reduces costs. Furthermore, contact resistances are reduced due to the direct electrical contact.

[0065] The invention is not limited to the embodiments described above. Rather, other variants of the invention can also be derived by a person skilled in the art without departing from the subject matter of the invention. In particular, all individual features described in connection with the individual embodiments can also be combined with one another in other ways without departing from the subject matter of the invention. Reference symbol list 2 motor vehicles 4-wheeler 6 electric motor 8 Energy storage 10 procedures 12 First step 14 Battery module 16 cases 18 battery cells 20 poles 22 guide holes 24 area 26 electrical contact 28 Push rod 30 basic shapes 32 rings 34 electrically conductive section 36 further section 38 End 40 connection 42 second step 44 Subsection 46 Management 48 additional guide holes 50 more push rods 52 segments 54 levers 56 Control rod

Claims

[1] Energy storage device (8) of a motor vehicle (2), comprising two battery modules (14), each having two poles (20) and each having a straight guide hole (22), and comprising a push rod (28) which is arranged to be transversely displaceable in the two guide holes (22), and which has an electrically conductive section (34), wherein by means of the electrically conductive section (34) one of the poles (20) of one battery module (14) can be electrically contacted with one of the poles (20) of the other battery module (14) by means of the electrically conductive section (34) by means of sliding the push rod (28), wherein the push rod (28) has a number of individual segments (52) corresponding to the number of battery modules (14), wherein each battery module (14) is assigned one of the segments (52). [2] Energy storage device (8) according to claim 1, characterized by, that each guide hole (22) in an area (24) is lined with an electrical contact (26) which is electrically contacted with one of the poles (20) of the respective battery module (14). [3] Energy storage device (8) according to claim 1 or 2, characterized by further battery modules (14), wherein the push rod (28) extends through all guide holes (22). [4] Energy storage device (8) according to claim 3, characterized by , that each of the poles (20) of each battery module (14) are electrically contacted by means of the same electrically conductive section (34). [5] Energy storage device (8) according to any one of the preceding claims, characterized by, that each guide hole (22) has a second electrical contact (26) by means of which a second area (24) is lined which is electrically contacted with the other pole (20) of the respective battery module (14), and that the push rod (28) has several electrically conductive sections (34) which are electrically insulated from each other and are each contacted with two of the electrical contacts (36). [6] Energy storage device (8) according to claim 5, characterized by , that the electrically conductive sections (34) are each formed by means of a cylinder. [7] Energy storage device (8) according to any one of claims 1 to 6, characterized by , that one of the ends (38) of the push rod (28) has a connection (40) which is electrically contacted with the electrically conductive section (34). [8] Energy storage device (8) according to any one of claims 1 to 7, characterized by a lever (54) which is in operative connection with the push rod (28). [9] Method (10) for manufacturing an energy storage device (8) according to one of claims 1 to 8, in which two battery modules (14) are provided, each having two poles (20) and each having a straight guide hole (22), and in which a push rod (28) having an electrically conductive section (34) is moved transversely in the two guide holes (22) such that, by means of the electrically conductive section (34), one of the poles (20) of one battery module (14) is electrically contacted with one of the poles (20) of the other battery module (14).

Images