Method for arranging a contact element, contact element and battery stack

Abstract

Method for arranging a contact element (1) on a battery cell (60) of a battery level (50) of a battery stack (40) for a battery device of a vehicle, characterized by the following steps: a) providing a contact element (1) with at least one contact plate section (10), a transition section (20) and a positive pole section (30), wherein the contact plate section (10) surrounds the transition section (20) and the transition section (20) surrounds the positive pole section (30), and wherein furthermore the contact plate section (10) and the positive pole section (30) are spaced apart from one another and arranged parallel or at least substantially parallel, b) arranging the contact element (1) provided in step a) on the battery cell (60) of the battery level (50), wherein when arranging the contact element (1), the contact plate section (10) is arranged on a contact plate (51) of the battery level (50) and the positive pole section (30) is arranged on a positive pole (61) of the battery cell (60) of the battery level (50), and c) introducing at least one securing opening (22) according to method steps a) and b) into a perforation region (21) of the transition section (20) to create at least one securing section (23) in the transition section (20), wherein the securing section (23) is designed such that it can be melted open for securing purposes under high loads.

Description

The present invention relates to a method for arranging a contact element on a battery cell of a battery level of a battery stack for a battery device of a vehicle. Furthermore, the invention relates to a contact element for a battery cell of a battery plane of a battery stack for a battery device of a vehicle, having a contact plate section, a transition section and a positive pole section, wherein the contact plate section surrounds the transition section and the transition section surrounds the positive pole section, and wherein furthermore the contact plate section and the positive pole section are arranged spaced apart from one another and parallel or at least substantially parallel. The invention also relates to a battery stack, having at least one battery plane having at least one battery cell, wherein a contact element is arranged on the battery cell.Electrical energy stores are widely used in modern technology, for example in electric and / or hybrid vehicles. Possible embodiments of such energy stores are, for example, lithium-ion batteries. In order to increase the performance of such batteries, it is known, for example, to connect a plurality of individual battery cells in a battery plane electrically in parallel. For this electrically parallel interconnection, contact plates are usually used which consist of an electrically conductive material, for example copper. In order to achieve a further increase, two or more of these battery levels can be connected in series to form a battery stack. For this purpose, in particular the individual battery planes can be arranged on top of one another, in particular stacked, and electrically conductively connected. In this way, in particular for battery devices of vehicles, electrical energy stores having a high power density and at the same time a low pack size can be provided.According to the prior art, it is also known to use contact elements for establishing an electrically conductive contact between battery cells of two battery levels. Such contact elements are likewise manufactured at least in sections from an electrically conductive material. In other words, these contact elements are arranged in particular between two battery cells from two different battery levels. It is known here to configure the contact plate of the battery plane with receiving openings for a respective battery cell, wherein the contact element is connected to the contact plate in an electrically conductive manner on the one hand and passes through the receiving opening of the contact plate on the other hand and makes electrically conductive contact there with a pole of the battery cell, preferably a positive pole of the battery cell. The next battery cell can then be arranged, preferably with its negative pole, on a side of the contact element which is remote from the contact plate. This automatically results in a serial connection of the individual battery levels or of the battery cells of the battery levels.To increase the safety of a battery stack, it is also known to introduce securing sections into the contact elements, in which securing sections a cross section available for a current conduction between the battery cells is reduced. This can be provided, for example, by introducing securing openings into the contact element. In the event of an excessively high electrical load, in particular in the event of excessively high flowing currents, the contact element is fused at this reduced cross section and the electrically conductive connection is thereby interrupted. An increase in safety when using a battery stack with such contact elements can thereby be achieved.According to the prior art, it is known to produce the contact elements completely and then arrange them in the battery plane, in particular on the contact plate of the battery plane. Such a contact element is known, for example, from DE 10 2015 005 529 A1. In order to ensure the mechanical stability of the contact element, it is often provided that the securing openings for creating the securing sections with the reduced cross section are arranged in a region of the contact element which is provided for connecting the contact element to the contact plate. Furthermore, when introducing the securing openings, it must also be taken into account that the removal of material of the contact element at this point does not impair a mechanical stability of the entire contact element too much. This represents a limitation of the possible sizes of the introducible securing sections and thus of the safety that can be provided against, for example, overloading in the case of excessively high currents.Further contact elements are known from the publications DE 24 51 332 A1 and US 2008 / 0 182 160 A1.It is an object of the present invention to at least partially eliminate the disadvantages described above. In particular, it is the object of the present invention to provide, in a cost-effective and simple manner, a method for arranging a contact element, a contact element and a battery stack, by means of which both an arrangement of the contact element on a battery cell of a battery plane can be simplified, wherein, in particular, restrictions and boundary conditions during the introduction or provision of a securing section with a reduced cross section in the contact element can be reduced at the same time.The above object is achieved by a method for arranging a contact element having the features of independent claim 1, by a contact element having the features of independent claim 11 and by a battery stack having the features of subordinate claim 16. Features and details which are described in connection with the method according to the invention naturally also apply in connection with the contact element according to the invention and the battery stack according to the invention and vice versa, so that with regard to the disclosure reference is or can always be made reciprocally to the individual aspects of the invention.According to a first aspect of the invention, the object is achieved by a method for arranging a contact element on a battery cell of a battery level of a battery stack for a battery device of a vehicle. A method according to the invention is characterized by the following steps: a) providing a contact element having at least one contact plate section, a transition section and a positive pole section, wherein the contact plate section surrounds the transition section and the transition section surrounds the positive pole section, and wherein furthermore the contact plate section and the positive pole section are spaced apart from one another and arranged parallel or at least substantially parallel, b) arranging the contact element provided in step a) on the battery cell of the battery plane, wherein during the arrangement of the contact element the contact plate section is arranged on a contact plate of the battery plane and the positive pole section is arranged on a positive pole of the battery cell of the battery plane, and c) introducing at least one securing opening into a perforation region of the transition section in order to create at least one securing section in the transition section.Contact elements are used in battery stacks in order in particular to connect battery cells of different battery levels to one another in an electrically conductive manner. Preferably, a positive and a negative pole of the individual battery cells of the different battery levels are connected to one another. Terms relating to a positive pole and a negative pole of a battery cell can be interchanged throughout the application, so that battery cells with reverse polarity can also be connected by a method for arranging a contact element according to the invention. By means of a method according to the invention, such a contact element can be arranged on a battery cell of a battery level, wherein the battery level is part of a battery stack for a battery device of a vehicle. Such battery stacks can have a multiplicity of battery levels and these battery levels in turn have a multiplicity of battery cells, with the result that a large number of such contact elements must be arranged in order to produce or mount a battery stack.In a first step a) of a method according to the invention, the contact element which is to be arranged is provided. This contact element has at least one contact plate section, a transition section and a positive pole section. The contact plate section is provided for this purpose and is correspondingly designed to contact, in particular to contact electrically conductively, a contact plate of the battery level. By means of such a contact plate, the battery cells of a battery plane can be electrically conductively connected and thus connected in parallel. The positive pole section is that part of the contact element which is provided for making contact, in particular in an electrically conductive manner, with a positive pole of a battery cell and is correspondingly designed. A transition section is provided between the contact plate section and the positive pole section in the case of a contact element which can be arranged by a method according to the invention. In this case, the contact plate section, the transition section and the positive pole section are arranged relative to one another in such a way that the contact plate section surrounds the transition section and the transition section surrounds the positive pole section. The respective surrounding of the individual sections is preferably complete, but can also be configured only as a partial surrounding. In other words, the contact element has a structure which has the contact plate section on the outside, has the positive pole section on the inside and has the transition section therebetween. Furthermore, the contact plate section and the positive pole section are arranged relative to one another in such a way that they are spaced apart from one another on the one hand and are arranged parallel to one another or at least substantially parallel to one another on the other hand. In other words, the contact plate portion and the positive pole portion are arranged offset from one another along a depth direction. The depth direction corresponds in particular preferably to the longitudinal extent of the individual battery cells. The arrangement of the transition section between the contact plate section and the positive pole section automatically results in the transition section having a surface orientation which is formed non-parallel or at least substantially non-parallel to the contact plate section and the positive pole section. For example, in the case of an essentially rotationally symmetrical contact element, the transition section can be designed conically. After completion of the first step a) of a method according to the invention, just one such contact element is provided and is available for further method steps.In the next step b) of a method according to the invention, the contact element provided in step a) is arranged on the battery cell of the battery plane. This arrangement is carried out in particular in such a way that the contact plate section of the contact element is arranged on the contact plate of the battery plane. As described above, the contact plate section is in particular also provided for this use and is correspondingly designed. At the same time, the positive pole section of the contact element is arranged in step b) on a positive pole of the battery cell of the battery plane. Here too, as already described above, the positive pole section is provided and formed accordingly for this use. In particular, the transition section enables and provides that the contact plate section and the positive pole section of a contact element according to the invention are arranged spaced apart from one another. In this way, a receiving opening in the contact plate, in which the battery cell, in particular the positive pole of the battery cell, is arranged, can be penetrated by the positive pole section of the contact element. In this case, the contact plate section of the contact element is arranged on a side of the contact plate facing away from the battery cell, the positive pole section passes through the opening and can thus contact the positive pole of the battery cell. In particular, after completion of the arrangement of the contact element, an electrically conductive connection can be established between the positive pole via the contact element to the contact plate of the battery plane.In the next step c) of a method according to the invention, at least one securing opening is now introduced into a perforation region of the transition section. The perforation region can fill the entire transition section or only parts of the transition section. By inserting the securing opening, a securing section is simultaneously created in the transition section. In other words, the fuse opening provides a hole in the contact element, which is thereby no longer available in particular for conducting current between the battery cell and the contact plate. The entire electrical line of the contact element is thus provided in the region of the transition section only by the at least one securing section. The at least one securing section thus represents the region of the contact element which is subjected to particular stress in the event of an overload and can thereby melt in the event of too high a load. This can provide protection of the battery cell and thus of the entire battery stack against damage in the event of an overload occurring.Overall, a method according to the invention brings several advantages. It is essential to the invention in a method according to the invention in particular that the securing opening is only introduced into the contact element at a point in time after the contact element is arranged on the battery cell of the battery plane. An impairment of the mechanical stability of the contact element due to securing openings already introduced during the production of the contact element can thereby be avoided. The contact element used can thus be formed lighter or thinner overall, since the weakening of the mechanical stability by the inserted securing opening does not have to be compensated by the remaining material of the contact element. Furthermore, in a method according to the invention, the advantage results that the securing section is introduced into a perforation region of the transition section between the contact plate section and the positive pole section. This transition section represents a part of the contact element which is not subjected to mechanical stress, or at least only a small amount of stress. Due to the already effected arrangement of the contact element, in step c) the securing opening can also be introduced in the perforation region of the transition section without limiting the size. In this way, it is possible to provide particularly small fuse sections in the contact element. However, such a small fuse section is melted through even in the event of an overload which is smaller than in the case of the fuse sections of the known contact elements of the prior art. In this way, it can be provided in particular that, in the event of an internal faulty behavior of one of the battery cells, for example in the event of a short circuit in this battery cell, a passivation of this one specific battery cell can be carried out particularly easily and reliably and in particular automatically. Furthermore, an increase in the safety against damage due to overload can also be provided for the entire battery stack in this way. In summary, the arrangement of a contact element can thus be simplified by a method according to the invention, since the contact elements have a greater mechanical stability during the arrangement. The mounting of the contact element can thus take place more quickly. In addition, the possibility of particularly small safety sections can increase the safety during the operation of a battery stack against damage in the event of overload.Preferably, a method according to the invention can be further developed to the effect that in step c) a single securing opening is introduced and a single securing section is thereby created. In this way, a free cross section of the securing section which is available for the power line can be adjusted particularly easily and with high precision. Moreover, the introduction of a single securing opening represents only a single working step, so that the entire introduction of the securing opening can be simplified overall. As a result of this further development of a method according to the invention, the arrangement of the contact element can thus be further accelerated, resulting in a reduction in the production costs of the battery stack.In addition, a method according to the invention can preferably be further developed to the effect that the securing opening is formed annularly in sections, wherein an extent of the securing opening corresponds to the extent of a full ring by over 75%, preferably over 85%, particularly preferably over 95%. Such a partially ring-shaped securing opening represents a particularly preferred embodiment. In particular in the case of a contact element whose transition section is conical, a securing opening which is annular at least in sections represents a favorable embodiment. In other words, the securing opening is designed as an annular groove in this case. The securing opening can extend over a major part of the extent of a full ring, preferably significantly over 75%, in particular particularly preferably even over 95% of the extent of a full ring. Free cross sections of the securing section for the current flow between the positive pole of the battery and the contact plate of less than 0.1 mm 2 can thereby be achieved. Safety against an overload occurring during operation of the battery stack can thereby be further increased.Furthermore, in a method according to the invention, it can be provided that the introduction of the at least one securing opening in step c) is carried out by a laser perforation. In laser perforations, laser beams are used to melt or even evaporate the material of the contact element, in particular of the perforation region. The use of laser beams can increase the local accuracy of the introduction of the securing opening. A particularly precise introduction of the securing opening or of the securing section, in particular also of filigran structures of the securing opening or of the securing section, into the perforation region of the transition section can thus be provided by the use of laser perforation.In addition, a method according to the invention can be further developed to the effect that material of the perforation region is vaporized by the laser perforation, wherein the vaporized material is preferably suctioned off. By evaporating the material of the perforation region, it is possible in particular to prevent molten material of the perforation region from remaining on the contact element in an uncontrolled manner, in particular. Undesired contact bridges across the securing opening, which are formed by the melted material, can thereby be avoided. The preferred removal by suction of the vaporized material can moreover ensure that the vaporized material does not deposit in an uncontrolled manner in the region of the contact element. A particularly clean and secure method of introducing the at least one securing opening can be provided in this way.Furthermore, a method according to the invention can be configured such that, during the arrangement in step b), the contact plate section of the contact element is fastened to the contact plate and the positive pole section of the contact element is fastened to the positive pole of the battery cell. The fastening of the contact plate section to the contact plate and the positive pole section to the positive pole represents a mechanical fastening of the respective elements to one another. In this way, a relative positioning of the individual components, in particular of the contact element, the contact plate and the battery cell, with respect to one another can be ensured. By ensuring the mechanical fastening, it can simultaneously and additionally also be ensured that an electrically conductive connection is produced between the components. In this way, a flow of electrical charge between the contact plate and the positive pole of the battery cell via the contact element can be ensured.In addition, a method according to the invention can be further developed to the effect that the contact plate section of the contact element is fastened to the contact plate and the positive pole section is fastened to the positive pole of the battery cell by a fastening device in a materially integral manner, in particular that the contact plate section of the contact element is fastened to the contact plate and the positive pole section is fastened to the positive pole of the battery cell by a laser device in a materially integral manner by laser welding. The preferred cohesive fastening of the individual elements to one another by a fastening device makes it possible in particular to avoid the need for further fastening elements, such as screws, clamps or the like, for example, in order to fasten the contact element to the contact plate or to the positive pole section. A mechanical complexity of both the fastening process and of the entire battery stack can thereby be reduced. Particularly preferably, a laser device can be used for this cohesive fastening, by means of which the contact plate section is laser welded to the contact plate and the positive pole section is laser welded to the positive pole. By means of this laser welding, the materials of the components involved, that is to say of the contact plate section and the contact plate or of the positive pole section and the positive pole, are locally melted and are thereby connected to one another in a materially bonded manner. This represents a particularly simple and therefore preferred cohesive fastening of the contact element to the contact plate and to the positive pole of the battery cell.Particularly preferably, a method according to the invention can be further developed in that the fastening device used in step b), in particular the laser device, is used for introducing the at least one securing opening in step c). In this way, it can be made possible, for example, that the fastening of the contact element to the contact plate and to the positive pole and the introduction of the securing opening can be carried out without any need to change the equipment used therebetween. The arrangement of a contact element can be accelerated overall in this way. Overall, this saving in time during the production and assembly of a battery stack also makes it possible to save costs. By using a laser device, the advantages of introducing the securing opening by a laser perforation, which have already been described above, can additionally be provided.Furthermore, in the method according to the invention, it can be provided that an insulation volume of the battery plane, which is bounded at least in sections on one side by the transition section, is at least partially filled with an insulation material. Such an insulation volume represents in particular a cavity which is bounded at least in sections by the transition section of the contact element. Further limitations of the insulation volume can be, for example, the contact plate and the battery cell or else, for example, an insulation plate of the battery plane. By at least partially filling with an insulation material, it is possible to prevent unfilled volumes from remaining in the battery level of the battery stack. By using an insulation material, a better electrical insulation can be provided at the same time, wherein in particular an undesired conduction of current through this insulation volume can be prevented. Furthermore, by filling the insulation volume, a mechanical stability of the entire battery stack can also be increased.According to a preferred development of a method according to the invention, it can furthermore be provided that the insulation material has at least one of the following properties:- flowable - flowable- free-flow flow-capable- curing- dimensionally stableThis list is not concluded, so that the insulation material can also have further properties, insofar as technically expedient and possible. The individual properties can be identified by the insulation material individually or simultaneously. It is also conceivable for a plurality of the properties to be provided in chronological succession by the insulation material. Thus, for example, a flowable or free-flowing insulation material can be filled into the insulation volume in particular through the securing opening, wherein it subsequently cures and finally assumes a dimensionally stable shape. A variety of filling of the insulation volume by the insulation material can be provided in this way.According to a second aspect of the invention, the object is achieved by a contact element for a battery cell of a battery plane of a battery stack for a battery device of a vehicle, having a contact plate section, a transition section and a positive pole section, wherein the contact plate section surrounds the transition section and the transition section surrounds the positive pole section, and wherein furthermore the contact plate section and the positive pole section are spaced apart from one another and arranged parallel or at least substantially parallel. A contact element according to the invention is characterized in that the transition section has a perforation region for introducing at least one securing opening for creating at least one securing section.A contact element according to the invention is provided for providing an electrically conductive connection between a contact plate of a battery plane and a positive pole of a battery cell. For this purpose, the contact element has a contact plate section which is provided and designed for arrangement on a contact plate of a battery plane. At the same time, the contact element has a positive pole section which is correspondingly provided and designed for arrangement on a positive pole of a battery cell. The contact plate section surrounds the positive pole section, wherein a transition section is arranged between the contact plate section and the positive pole section. Thus, for example in the case of an at least substantially rotationally symmetrical configuration of a contact element, the contact plate section is arranged on the outside and the positive pole section on the inside, wherein the transition section is located between the contact plate section and the positive pole section. The contact plate section preferably completely surrounds the transition section, but can also only partially surround the latter. The same applies to the transition section and the positive pole section, so that the transition section preferably completely surrounds the positive pole section, but can also only partially surround it. In addition, the contact plate section and the positive pole section are provided on the contact element in such a way that they are arranged at a distance from one another and are arranged parallel or at least substantially parallel to one another. In other words, the contact plate section and the positive pole section are arranged spaced apart from one another in a depth direction, wherein the depth direction preferably corresponds at least substantially to the longitudinal extent of the battery cell. This means in particular that the transition section, which extends between the contact plate section and the positive pole section, has a surface orientation which is planar and not parallel or at least substantially not parallel to the contact plate section and to the positive pole section. In an at least substantially rotationally symmetrical configuration of a contact element, for example, the transition section can preferably be designed conically. In this way, it can be provided that the contact plate portion contacts the contact plate of the battery plane on one side and the positive pole portion engages with an arrangement opening of the contact plate in which the battery cell is arranged.According to the invention, it is provided in a contact element according to the invention that the transition section has a perforation region for introducing at least one securing opening for creating at least one securing section. In particular, it can be provided that this introduction of the at least one securing opening takes place only when the contact element is already arranged, preferably fastened, on the contact plate and the battery cell. In this way, the contact element can be arranged as a stable component, in particular without securing openings, on the battery cell and on the contact plate. The securing opening is only produced after completion of this arrangement in the perforation region of the transition section. The transition section particularly preferably represents a region of the contact element with little mechanical stress, since the attachment of the contact element to the contact plate is preferably effected in the contact plate section and the attachment of the positive pole section to the positive pole is effected. In this way, the contact element can be formed mechanically simpler overall and, for example, also lighter. Furthermore, no restrictions on the fuse opening and the at least one fuse section result from specifications which are predefined by the arrangement or mounting of the contact element on the battery plane. A better adaptation of the at least one securing opening and of the at least one securing section to the requirements of the electrical power to be secured can thereby be made possible. Overall, it is thus possible to simplify the mounting of a contact element according to the invention on a battery cell and at the same time to increase safety during the operation of a battery stack having such contact elements.Particularly preferably, the contact element according to the invention can provide that the contact element is arranged using a method according to the first aspect of the invention. In this way, all the advantages which have already been described in detail with respect to a method according to the first aspect of the invention arise, of course, also for a contact element which has been arranged using such a method according to the first aspect of the invention.In addition, in the case of a contact element according to the invention, it can be provided that the perforation region consists at least in sections of a evaporable material. In this way, it can be made possible for the introduction of the securing opening to be carried out by evaporation of this evaporable material. In particular, in contrast to simple melting, for example, no waste material arises which, in the worst case, produces an undesired conductive connection between, for example, the contact plate and the positive pole. It can particularly preferably be provided that the evaporable material is present only at those locations of the perforation area at which the securing opening is to be introduced. For example, the transition section can be made particularly thin in the area of the perforation area in order to create evaporable material there. A particularly simple introduction of the securing opening into the transition section can thereby be provided.A contact element according to the invention can also be designed such that, in a position of the contact element arranged on the battery cell of the battery plane, the transition section delimits at least in sections a side of an insulation volume of the battery plane at least on one side. Such an insulation volume can be filled with an insulation material in particular preferably. Other sides of the insulation volume can be bounded, for example, by the contact plate, the battery cell and / or an insulation plate of the battery plane. By means of such an insulation volume, in particular by means of an insulation volume filled with an insulation material, an even better insulation can be provided between the contact plate and, for example, the battery cell. In particular, it can thereby be avoided that unfilled volumes are present in the battery level. By filling the insulation volume, in particular a mechanical stability of the entire battery stack can also be increased.Furthermore, in the case of the contact element according to the invention, it can be provided that the contact element has fastening means, in particular fastening clamps, for fastening a negative pole of a battery cell of a further battery plane of the battery stack, wherein the fastening means are preferably arranged on the contact plate section. In this way, it is possible in particular in a particularly simple manner to provide a stackable nature of the individual battery levels of the battery stack. By providing fastening means on the contact element, in particular an integration of the fastening of the battery cells of the next battery level can already be provided by the contact element. An increase in the compactness of a battery stack can thereby be made possible.According to a third aspect of the invention, the object is achieved by a battery stack, having at least one battery plane having at least one battery cell, wherein a contact element is arranged on the battery cell. A battery stack according to the invention is characterized in that the contact element is formed according to one of the claims according to the second aspect of the invention and / or is arranged on the battery cell according to a method according to the first aspect of the invention. In this way, a battery stack according to the invention can provide the same advantages which have already been described in detail with respect to a contact element according to the second aspect of the invention and / or with respect to a method according to the first aspect of the invention.Further advantages, features and details of the invention will become apparent from the following description, in which exemplary embodiments of the invention are described in detail with reference to the drawings. The features mentioned in the claims and in the description can be essential to the invention individually or in any combination. The explanation of the embodiments describes the present invention solely in the context of examples. Of course, individual features of the embodiments can be freely combined with one another, insofar as technically expedient, without departing from the scope of the present invention. Elements with the same function and mode of operation are provided with the same reference numerals in the figures. They show schematically: FIG. 1 shows a method according to the invention for arranging a contact element according to the invention, FIG. 2 shows a battery stack according to the invention, and FIG. 3 shows a further embodiment of a contact element according to the invention.FIG. 1 shows the steps of a method according to the invention for arranging a contact element 1 on a battery cell 60. The battery cell 60 is part of a battery plane 50 of a battery pack 40 (each not shown) for a battery device of a vehicle. In each case, a view from above of the contact element 1 is shown on the left side, and a sectional view is shown on the right side. The top figure shows step a) of a method according to the invention and is denoted by A. The middle illustration shows step b) of a method according to the invention and is correspondingly denoted by B. In addition, the bottom figure shows step c) of a method according to the invention and is denoted by C. In the individual figures, in order to improve the clarity, only newly occurring elements are in each case usually provided with reference symbols.In step a) of a method according to the invention, a contact element 1 is provided. In the depicted embodiment of the contact element 1, the latter has, in particular, a contact plate section 10, a transition section 20 and a positive pole section 30. The positive pole section 30 is surrounded by the transition section 20, which in turn is surrounded by the contact plate section 10. In this substantially radially symmetrical embodiment of a contact element 1 according to the invention, the transition section 20 is of conical design. As a result, it can be provided in a particularly simple manner that the contact plate section 10 and the positive pole section 30 are arranged spaced apart from one another, in particular spaced apart from one another along a depth direction T. The depth direction T corresponds in particular to a longitudinal extent of the battery cell 60. At the same time, the contact plate section 10 and the positive pole section 30 are arranged substantially parallel to one another. The transition section 20 further comprises a perforation region 21, into which a securing opening 22 and thereby a securing section 23 will be introduced later in step c) of a method according to the invention. At the edge of the contact plate section 10, fastening means 11 designed as fastening clamps 12 are arranged. These serve for fastening a further battery cell 60 of a further battery plane 50 (in each case not shown).In the next step b) of a method according to the invention, the provided contact element 1 is arranged on the battery cell 60. This arrangement is carried out in particular in such a way that the positive pole section 30 is arranged on a positive pole 61 of the battery cell 60 and at the same time the contact plate section 10 is arranged on a contact plate 51 of the battery plane 50. The battery cell 60 can also be located, for example, in an insulation plate 52 of the battery plane 50 or can be arranged therein. As illustrated, particularly preferably, the contact plate section 10 can be fastened to the contact plate 51 and the positive pole section 30 to the positive pole 61 at fastening points 53. This fastening is particularly preferably carried out by a fastening device in a materially integral manner, particularly preferably by laser welding carried out by a laser device. A particularly secure, mechanical hold of the contact element 1 both on the contact plate 51 and on the positive pole 61 of the battery cell 60 can thereby be provided. Furthermore, the securing of an electrically conductive connection between the positive pole 61 via the contact element 1 to the contact plate 51 can be ensured particularly easily by this mechanical fastening.In the final step c) of a method according to the invention, a securing opening 22 is introduced in a perforation region 21 of the transition section 20. This automatically produces a securing section 23. Alternatively, a plurality of securing openings 22 and thus a plurality of securing sections 23 can also be produced. Furthermore, it can be provided particularly preferably that the same fastening device, in particular the laser device, is used for introducing the securing opening 22, which fastening device was used in step b) for fastening the contact element 1 at the fastening points 53 to the contact plate 51 or the positive pole 61. The mounting of the contact element 1 can thereby be simplified overall. Particularly preferably, during the introduction of the securing opening 22, the material of the perforation region 21 is vaporized and particularly preferably suctioned off. For this purpose, it can be provided that the perforation region 21 consists at least in sections of a evaporable material. Contamination of the contact element 1 by the vaporized material can be avoided by the suction. As depicted, the securing opening 22 can preferably extend at least in sections annularly in the transition section 20. In this embodiment, the securing opening 22 extends over 95% of the extent of a full ring. The securing section 23 can thereby be designed to be particularly small. Particularly preferably, the securing section 23 can have a cross section for a current flow of less than 0.1 mm 2. A particularly good protection against an overload can be provided in this way, since in the event of an excessively high current flow through the safety section 23, the latter fuses and the electrical connection between the positive pole 61 and the contact plate 51 is thereby interrupted.Overall, by using a method according to the invention, the arrangement of a contact element 1 on a battery cell 60 of a battery plane 50 can be simplified. In particular, because the securing opening 22 is only introduced into the contact element 1 when it is already arranged, preferably fastened, on the battery cell 60, it can be provided that the contact element 1 can be formed in a simpler and mechanically more stable manner overall. Restrictions and boundary conditions, which are caused during the planning of the securing section 23 on the basis of mechanical considerations with regard to stability of the entire contact element 1, can also be dispensed with by the use of a method according to the invention.FIG. 2 shows a section of a battery stack 40 according to the invention. In particular, two battery levels 50 and of these in each case one battery cell 60 are shown. A contact element 1 according to the invention ensures an electrically conductive connection of a positive pole 61 of the one battery cell 60 to the negative pole 62 of the battery cell 60 in the further battery plane 50. The contact element 1 is connected in a materially integral manner to a contact plate 51 of the lower battery plane 50 and to the positive pole 61 of the corresponding battery 60 at fastening points 53. Fastening means 11 designed as fastening clamps 12 ensure a hold of the battery cell 60 of the upper battery level 50, which fastening means are arranged in particular on the contact plate section 10 of the contact element 1. As a result, a stackable nature of the individual battery planes 50 of the battery stack 40 along a depth direction T, which corresponds to a longitudinal extent of the battery cells 60, can be provided particularly easily. The contact element 1 has, in particular, a contact plate section 10, a positive pole section 30 and a transition section 20 arranged therebetween. Since the contact plate section 10 and the positive pole section 30 are arranged spaced apart along the depth direction T, the transition section 20 likewise extends at least partially along the depth direction T; in the embodiment shown, the transition section 20 is in particular of conical configuration. An insulation plate 52 further ensures a mechanically stable arrangement of the battery 60 and at the same time electrical insulation. According to the invention, a perforation region 21 is provided in the transition section 20 with little mechanical stress, into which perforation region a securing opening 22 and thus a securing section 23 is introduced. According to the invention, this introduction of the securing opening 22 takes place only when the contact element 1 is already arranged, preferably fastened, on the contact plate 51 or the positive pole 61 according to a method according to the invention. In this way, the contact element 1 can be designed to be mechanically particularly simple, as a result of which, for example, a reduction in the thickness of the contact element 1 can also be provided. Boundary conditions for planning the securing section 23, which are aimed only at a mechanical stability of the contact element 1, can also be avoided. The design of the safety section 23 is thus effected only for reasons which take into account electrical safety, for example against overload. Safety during the operation of a battery stack 40 can thereby be increased. Furthermore, FIG. 2 shows an insulation volume 70 which is bounded at least in sections by the transition section 20 of the contact element 1. Further sides of the insulation volume 70 form, for example, the contact plate 51 and the insulation plate 52. The insulation volume 70 is furthermore filled with an insulation material 71 which, for example, is flowable or free-flowing during filling, subsequently cures and finally fills the insulation volume 70 in a dimensionally stable manner. In this way, on the one hand, better electrical insulation can be provided between the battery 60 and the contact plate 51. On the other hand, by filling cavities, a mechanical stability of the battery stack 40 can be increased.FIG. 3 shows a further possible embodiment of a contact element 1 according to the invention. In this embodiment, too, the contact element 1 is at least substantially rotationally symmetrical. A plan view of the contact element 1 according to the invention is shown. It is clearly visible in this embodiment too that the contact plate section 10 surrounds the transition section 20, which in turn has a perforation region 21 for arranging a securing opening 22 and a securing section 23. Furthermore, the transition section 20 again surrounds the positive pole section 30, and fastening means 11 likewise designed as fastening clamps 12 are also arranged on the outer edge of the contact plate section 10. In comparison, for example, with the embodiment of a contact element 1 according to the invention shown in FIG. 1, the securing opening 22 and the securing section 23 are now of different design in this embodiment. Thus, in this embodiment, it is provided that the securing section 23 comprises the positive pole section 30 substantially semicircular. In other words, this means that the contact points between the securing section 23 and the contact plate section 10 or the securing section 23 and the positive pole section 30 are opposite each other with respect to the center of the contact element 1. A securing section 23 with a large longitudinal extent can be provided in a particularly simple manner in this way. Melting through of the fuse section 23, for example in the event of an excessively high current load, can thereby be ensured in a particularly simple manner. It can also be provided by such a configuration of the securing section 23 that it at least substantially also has spring properties. When arranging the contact element 1 on a contact plate 51 and a positive pole 61 of a battery cell 60 (in each case not shown), it can thereby be made possible for the positive pole section 30 to be pressed against the positive pole 61 of the battery cell 60 by the spring action of the securing section 23. This already ensures reliable contacting of the positive pole section 30 on the positive pole 61 of the battery cell 60. Fastening, in particular welding by a laser device, of the positive pole section 30 to the positive pole 61 of the battery cell 60 can also be simplified as a result.Reference numerals denote reference numerals1 Contact element 10 Contact plate section 11 Fastening means 12 Fastening bracket 20 Transition section 21 Perforation region 22 Securing opening 23 Securing section 30 Positive pole section 40 Battery stack 50 Battery plane 51 Contact plate 52 Insulation plate 53 Fastening point 60 Battery cell 61 Positive pole 62 Negative pole 70 Insulation volume 71 Insulation material T Depth direction

Claims

Method for arranging a contact element (1) on a battery cell (60) of a battery plane (50) of a battery stack (40) for a battery device of a vehicle, characterized bythe following steps: a) providing a contact element (1) having at least one contact plate section (10), a transition section (20) and a positive pole section (30), wherein the contact plate section (10) surrounds the transition section (20) and the transition section (20) surrounds the positive pole section (30), and wherein furthermore the contact plate section (10) and the positive pole section (30) are spaced apart from one another and arranged parallel or at least substantially parallel, b) arranging the contact element (1) provided in step a) on the battery cell (60) of the battery plane (50), wherein, when the contact element (1) is arranged, the contact plate section (10) is arranged on a contact plate (51) of the battery plane (50) and the positive pole section (30) is arranged on a positive pole (61) of the battery cell (60) of the battery plane (50), and c) introducing at least one securing opening (22) according to method steps a) and b) into a perforation region (21) of the transition section (20) in order to create at least one securing section (23) in the transition section (20), wherein the securing section (23) is designed such that it can be melted on under high load for securing purposes.Method according to claim 1, characterised in that in step c) a single securing opening (22) is introduced and thereby a single securing section (23) is created.Method according to claim 2, characterised in that the securing opening (22) is formed annularly in sections, wherein an extension of the securing opening (22) over 75%, preferably over 85%, particularly preferably over 95%, corresponds to the extension of a full ring.Method according to one of the preceding claims, characterized in that the introduction of the at least one securing opening (22) in step c) is carried out by laser perforation.Method according to claim 4, characterised in that material of the perforation region (21) is vapourised by the laser perforation, wherein this vapourised material is preferably sucked off.Method according to one of the preceding claims, characterized in that, during the arrangement in step b), the contact plate section (10) of the contact element (1) is fastened to the contact plate (51) and the positive pole section (30) of the contact element (1) is fastened to the positive pole (61) of the battery cell (60).Method according to Claim 6, characterized in that the contact plate section (10) of the contact element (1) is fastened to the contact plate (51) in a materially integral manner and the positive pole section (30) is fastened to the positive pole (61) of the battery cell (60) by a fastening device, in particular in that the contact plate section (10) of the contact element (1) is fastened to the contact plate (51) in a materially integral manner and the positive pole section (30) is welded by a laser device to the positive pole (61) of the battery cell (60).Method according to claim 7, characterised in that for introducing the at least one securing opening (22) in step c) the fastening device used in step b), in particular the laser device, is used.Method according to one of the preceding claims, characterized in that an insulation volume (70) of the battery plane (50), which is bounded at least in sections on at least one side by the transition section (20), is at least partially filled with an insulation material (71).Method according to claim 9, characterised in that the insulation material (71) has at least one of the following properties: - flowable - free-flowing - curing - dimensionally stableBattery stack (40), having at least one battery plane (50) with at least one battery cell (60), wherein a contact element (1) is arranged on the battery cell (60), the contact element (1) having a contact plate section (10), a transition section (20) and a positive pole section (30), wherein the contact plate section (10) surrounds the transition section (20) and the transition section (20) surrounds the positive pole section (30), and wherein furthermore the contact plate section (10) and the positive pole section (30) are arranged spaced apart from one another and parallel or at least substantially parallel, characterized in that the transition section (20) has a perforation region (21) for introducing at least one securing opening (22) for creating at least one securing section (23), wherein the securing section (23) is designed such that it can be melted on under high load for securing purposes, wherein the contact element (1) is arranged using a method according to any one of claims 1 to 10.Battery stack (40) according to Claim 11, characterized in that the perforation region (21) consists at least in sections of a evaporable material.Battery stack (40) according to one of Claims 11 to 12, characterized in that, in a position of the contact element (1) arranged on the battery cell (60) of the battery plane (50), the transition section (20) delimits, at least in sections, a side of an insulation volume (70) of the battery plane (50) at least on one side.Battery stack (40) according to one of Claims 11 to 13, characterized in that the contact element (1) has fastening means (11), in particular fastening clamps (12), for fastening a negative pole (62) of a battery cell (60) of a further battery plane (50) of the battery stack (40), wherein the fastening means (11) are preferably arranged on the contact plate section (10).

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