Cell connector and method for contacting at least two galvanic cells - Patents.com

Abstract

The present invention relates to a cell connector (1) for connecting at least two conductors (2) and / or Litz wires (3) to one another, which consists of at least one substantially stripe-shaped element (4). The cell connector (1) of the invention is characterized by at least five sections (4.1, 4.2, 4.3, 4.4, 4.5) arranged successively in the longitudinal direction (L) of the stripe-shaped element (4), in which the first section (4.1) forms a first half (5.1) of the closure element, the second section (4.2) forms a first clamping surface (6.1), the third section forms a bent element (7), the fourth section (4.4) forms a second clamping surface (6.2), the fifth section (4,5) forms a second half (5.2) of the closure element, and the third section (4.3) forms a first half (5.1) of the closure element, the second section (4.2) forms a first clamping surface (6.1), the third section (4.4) forms a second clamping surface (6.2), the fifth section (4,5) forms a second half (5.2) of the closure element, and the third section (4.3) forms a second half (5.2) of the closure element, in which the first section (4.1) and the second section (4.2) form a second clamping surface (6.3). , the fourth section (4.4) and the fifth section (4.5), so that in the folded state of the stripe-shaped element (4), at least a part of the first clamping surface (6.1) and the second clamping surface (6.2) face each other, thereby forming a receiving portion (9) for the conductor (2) and / or the Litz wire (3), and the first section (4.1) and the fifth section (4,5) are connectable to each other in order to fix the at least one stripe-shaped element (4) in the folded state, when the stripe-shaped element (4) is in the folded state.

Description

Technical Field

[0001] The present invention relates to a cell connector for connecting at least two conducting wires and / or busbars to each other, consisting of at least one substantially Strip-shaped element, and a method for making a contact connection between at least two galvanic cells using at least one such cell connector.

Background Art

[0002] A galvanic cell, also referred to as a battery cell, is a device that converts chemical energy into electrical energy. Such galvanic cells can also be used to supply electrical energy to mobile devices. Here, various embodiments of galvanic cells and battery modules consisting of a plurality of galvanic cells circuit-connected to each other are known from the general prior art. For example, individual galvanic cells can be connected in series to boost the voltage output from the galvanic cells. To increase the capacity of a battery module consisting of a plurality of galvanic cells, a plurality of galvanic cells connected individually or in series can also be connected in parallel. The electrical connection of individual galvanic cells is here effected via corresponding contact connection elements. In particular, in the case of so-called pouch cells, aluminum or copper conducting wires are used therefor.

[0003] In order to robustly connect the conductors, these are welded. Such connections require a minimum cross-sectional area because a relatively large current is transmitted through the conductor and thus also through the corresponding connection point. If the cross-sectional area is excessively small, the connection point may be heated so strongly that damage or destruction of the individual components of the pouch cell and / or the battery module is feared. In order to ensure a high process reliability when forming a welded connection between a plurality of conductors, several problems need to be overcome. For example, the two conductors to be connected need to abut against each other with as large an area as possible. This is because if the contact connection between the two conductors is insufficient, a gap may occur between the conductors after welding the conductors. Therefore, the conductors to be connected are often pressed together before the welding process by means of spring-type clamp fingers, a clamp frame, etc., and the gap between the conductors is adjusted. Here, a self-frame is often used as the mating receiver. Nevertheless, due to tolerances when bending the conductors or stacking the galvanic cells, a gap may be formed between the conductors to be connected due to the collapse of the galvanic cells during transport and due to an incorrect setting of the clamping force of the clamping device. Furthermore, the clamping force cannot be arbitrarily selected to be large because the maximum clamping force is limited by the stability or strength of the self-frame.

[0004] Typically, the first conductor of the conductor pair to be welded comprises aluminum or an aluminum alloy, and the further conductor comprises copper or a copper alloy. Thereby, a material-bonding connection is established between two different materials. Therefore, it is particularly difficult to select and maintain the correct welding parameters. For example, there is a significant risk that penetration welding from the conductor into the self-frame may occur. When a plurality of galvanic cells are connected in parallel, a plurality of layers of conductors are welded to each other, whereby tolerances and stacking errors may accumulate.

[0005] Typically, the conductors of the pouch cells are connected by laser welding. Another welding method such as ultrasonic welding can also be applied, but this is accompanied by inherent drawbacks. For example, ultrasonic welding requires access from both sides to the workpiece to be welded and a large space for pulling the workpiece. Therefore, ultrasonic welding equipment is relatively large. In addition, the electrodes used for welding are consumable. Furthermore, the conductors to be connected may adhere to the welding electrodes.

[0006] Furthermore, it is known to circuit-connect a plurality of galvanic cells in parallel by means of so-called cell connectors. The cell connectors are, for example, metal Strip-shaped elements. If the galvanic cells to be connected have a height offset from each other, the cell connector abuts obliquely on the conductor to be connected, so that only a point-like or linear contact occurs between the cell connector and the conductor. As a result, the cross-sectional area of the electrical contact connection of the galvanic cells to be connected is reduced. In order to compensate for such a height offset, such a cell connector can be curved along at least one section. However, in this case, the problem arises that the cell connector must be positioned accurately in order to be able to produce a welding seam of sufficient quality. The more numerous the cells connected to the cell connector, the more serious the problems resulting from the height offset can become. For example, in a single cell, the height offset may be so large that a gap occurs between the conductor and the cell connector. In addition, it is known to provide the cell connector with an opening for guiding the conductor therethrough. However, this requires the conductor to be passed through the cell connector, and since the conductor is mechanically loaded, there is a risk of damage to the conductor. In addition, there is also a risk that the laser beam hits the galvanic cell to be contact-connected. To avoid this, strict requirements are imposed on the positioning of the galvanic cells or conductors to be connected, and the cell connector in the laser welding machine.

[0007] Furthermore, from Patent Document 1, a method of making electrical terminals in contact connection with a battery conductor is known. In many electronic devices, the battery is connected to the electrical circuit of the electronic device by welding or brazing. However, since the structural space available within the electronic device is small, the accessibility to the corresponding welding or brazing location is poor. The method disclosed in this cited document describes forming a metal strip on the conductor of the battery cell, which increases the area and improves the accessibility, so that the conductor can be more easily brought into contact connection with a further current-carrying component or an electrical terminal. For this purpose, a metal strip is flatly placed on the conductor for each conductor, curved around it, and as a result, the metal strip surrounds the conductor over as wide an area as possible. The layer structure consisting of the conductor and the metal strip thus formed is then mounted in an ultrasonic welding machine, and the individual layers are connected by ultrasonic welding. Subsequently, the layer structure fixed by welding is cut to a predetermined size. [Patent Document 1] US 6,641,027 B2 [Summary of the Invention] [Problems to be Solved by the Invention]

[0008] The problem underlying the present invention is to provide a cell connector for connecting at least two conductors and / or litz wires to each other, by means of which the conductors or litz wires to be connected are reliably mutually aligned, thereby reducing the effort while establishing a reliable welded connection between the conductors and / or litz wires to be connected. A further problem of the present invention is to provide a method for making contact connection between at least two galvanic cells by means of at least one such cell connector. [Means for Solving the Problems]

[0009] According to the present invention, these problems are solved by a cell connector having the features of claim 1 and a method for contact-connecting at least two galvanic cells having the features of claim 10. Advantageous embodiments and developments are apparent from the dependent claims.

[0010] At least one substantially Strip-shaped The cell connector for connecting at least two conductors and / or litz wires to each other, which consists of at least one element, according to the present invention Strip-shaped Has at least five sections arranged continuously in the longitudinal direction of the element. Here, the first section forms the first half of the closing element, the second section forms the first clamping surface, the third section forms the bending element, the fourth section forms the second clamping surface, and the fifth section forms the second half of the closing element. The third section is configured such that the first section and the second section can be folded around a folding axis extending through the third section in a width direction orthogonal to the longitudinal direction with respect to the fourth section and the fifth section. Thereby, Strip-shaped The element is movable into a folded state, in which at least a part of the first clamping surface and the second clamping surface substantially face each other in a thickness direction extending orthogonally to the longitudinal direction and the width direction, thereby forming a receiving portion for the conductor and / or litz wire. The first section and the fifth section are Strip In the folded state of the element, at least one Strip-shaped Elements can be connected to each other to fix the folded state.

[0011] Using the cell connector of the present invention, particularly reliable mutual adjustment and fixation of the connected conductors and / or litz wires are possible, which improves the process reliability for materially connecting the conductors and / or litz wires in the welding process following the mutual adjustment. Therefore, by folding at least one substantially Strip-shaped Element (hereinafter referred to as "closing"), the conductors and / or litz wires to be connected are pressed against each other, thereby compensating for the stacking tolerance. At least one substantially Strip-shapedWhen the element is closed, the conductors and / or litz wires to be connected are fixed and cannot move relative to each other or thus become detached from each other even during the transportation process to the welding station. At least one substantially Strip-shaped The element completely circumferentially surrounds the receiving part in the folded state. Thus, the fourth section or the second clamping surface forms a substrate or base material for the laser welding process, which makes through-welding of the conductors and / or litz wires difficult. The second section or the first clamping surface is arranged between the conductors and / or litz wires to be connected and the laser light source in the laser welding process and thus serves as a material reservoir. Thus, it is possible to similarly melt the second section and incorporate it into the material-bonded connection between the conductors and / or litz wires to be connected. Thereby, potential gaps can be filled. Furthermore, by appropriate material selection, the weld connection can be properly alloyed.

[0012] Furthermore, the manufacturing costs for making contact connections between a plurality of galvanic cells via conductors can also be reduced by using the cell connector of the present invention. For example, the cumbersome adjustment of the clamping tools used to press the conductors to be connected against each other is omitted. By using the cell connector of the present invention, the conductors to be connected are pressed against each other particularly simply and reliably. Thereby, different cell shapes can also be flexibly connected to each other because there is no need to change the clamping technique used to press the conductors. Correspondingly, a flexible laser cavity of a certain format or version can be considered. Thereby, the program costs of the laser welding machine used to weld the conductors and / or litz wires to be connected are also reduced. Since the weld seam is not covered by complex clamping techniques, the generated weld seam can be inspected more simply. Furthermore, the cell connector of the present invention can be manufactured particularly simply and inexpensively. Thus, the cell connector is, for example, a simple plate bending and punching part. The cell connector of the present invention in an advantageous form can also be punched out of a single plate.

[0013] In an advantageous development form of the cell connector, it is contemplated that the third section includes at least one perforation, hinge and / or elastic material, and / or is at least partially contoured. The third section is used to enable bending or folding of the individual sections of the cell connector in order to close or fold at least one substantially strip-shaped element. By introducing a perforation into the third section, the bending stiffness of the third section is reduced, whereby the substantially Strip-shaped element can be bent particularly easily about the folding axis. The perforation can be configured arbitrarily. For example, this can be one or more rectangular punches. However, the punches can also have any shape. Thus, the punches or perforations can be implemented, for example, in an elliptical, circular, or any polygonal shape. In addition to or instead of the perforation, a hinge can be incorporated into or formed in the third section. By means of a two-part hinge, the cell connector can be formed by connecting at least two substantially Strip-shaped elements to each other. Here, the first substantially Strip-shaped element includes the first and second sections, and the second substantially Strip-shaped element includes the fourth and fifth sections. For example, the third section can have or be formed by a film hinge. Additionally or alternatively, the third section can include an elastic material. For example, the third section can include rubber, such as an elastomer. Since the elastic material can be bent, stretched, or compressed particularly easily, at least one substantially Strip-shaped element can be transitioned into a folded state particularly easily. A joint can also be incorporated into or formed in the third section. Additionally or alternatively, the third section can be contoured. For example, the third section can be configured like the cover of a joint of an accordion or a joint bus. This is at least one Strip-shapedIt further facilitates the folding or bending of the individual sections of the element. The profiling section can here be optionally implemented and, in particular, can have any orientation in the third section. For example, the profiling section preferably extends in the longitudinal direction. Thereby, a certain minimum bending stiffness is ensured in the width direction and the bending stiffness around the folding axis is reduced. Thus, at least one substantially Strip-shaped element can be transitioned into the folded state particularly easily, and the inclination of the opposing sections is prevented or reduced. Thereby, it is ensured that in the folded state the second and fourth sections, or the first and second clamping surfaces, are maintained in a state adjusted as closely as possible parallel to each other, which improves the reliability of the crimping of the conductors and / or litz wires to be connected.

[0014] Corresponding to a further advantageous form of the cell connector, the first section and the fifth section are designed to be shape-coupled, in particular by bending, beading, rounding, or caulking at least one of the sections, and / or the first section and the fifth section are designed to be friction-coupled and / or material-coupled, in particular by riveting, screwing, welding, and / or gluing the sections. Thereby, the first and fifth sections can be fixed particularly reliably. Thereby, an undesired opening of at least one substantially Strip-shaped element from the folded state can be reliably prevented. In particular, the first and fifth sections have geometric shapes that are correspondingly adapted to each other, whereby these sections can be connected particularly easily. For example, the first section can be implemented as a tab and the fifth section can be implemented as a pocket for receiving the tab. Thus, the tab can be bent into the pocket, whereby the first and fifth sections can be connected to each other particularly easily. In addition, this connection can be fixed, for example, by crimping. It is also possible to fix the shape-coupled connection between the first section and the fifth section, for example, by brazing the two sections. Generally, at least one substantially Strip-shapedThe element can be fixed in the folded state by covering it with additional clamping means or fixing it in another way. For example, a relatively thin rubber band can be placed over the element in the folded state. For this purpose, a shrink tube can also be used, for example. Strip-shaped For this purpose, for example, a shrink tube can also be used.

[0015] In a further advantageous form of the cell connector, it is furthermore contemplated that the second section has a notch for forming a welding window, in particular a substantially rectangular notch, which extends completely through the second section in the thickness direction, and the long side of this notch extends in the longitudinal direction. By introducing the notch into the second section or the first clamping surface, the laser of the laser welding machine can directly access the conductor and / or the litz wire to be connected. Thus, there is no need to weld through the second section or the first clamping surface. As a result, the thermal load on the elements to be connected is reduced. Furthermore, it is possible to achieve a higher welding speed and / or a lower laser output. In addition, the generated weld seam can be visually inspected more easily. By the notch or the welding window extending particularly substantially in the longitudinal direction, the long side of the notch preferably coincides with the selected weld seam direction. It is also conceivable to implement the notch so that it is interrupted, so that the individual parts of the generated weld seam are alloyed by melting the material of the element. This allows the conductivity and / or mechanical load resistance of the weld seam to be adjusted more appropriately. Similar to the perforations introduced into the third section, the notch for forming the welding window can also be introduced into the second section, for example by punching out the notch. However, it is also possible to cut out the notch from the second section, for example by means of a laser beam or a water jet. Strip-shaped The elements can be alloyed by melting the material of the element. This allows the conductivity and / or mechanical load resistance of the weld seam to be adjusted more appropriately. Similar to the perforations introduced into the third section, the notch for forming the welding window can also be introduced into the second section, for example by punching out the notch. However, it is also possible to cut out the notch from the second section, for example by means of a laser beam or a water jet.

[0016] Corresponding to a further advantageous form of the cell connector, at least two elements arranged parallel to each other in the longitudinal direction Strip-shaped are from the second and / or fourth section in the width direction Strip-shapedIt extends away from the element and is connected via at least one web that extends in the longitudinal direction. Using such a cell connector, individual galvanic cells and / or cells connected in series can be connected in parallel particularly simply and reliably. Here, the web can have any form. In particular, the web extends longitudinally over the entire length of the second and / or fourth section. Thereby, the cross-sectional area of the web in the width direction is increased, and as a result, the heat load on the web due to a relatively large current can be reduced. In particular, the web, when viewed in the thickness direction, is substantially Strip-shaped having the same material thickness as the remaining section of the element. Thereby, the corresponding cell connector can be manufactured particularly simply. The cell connector can likewise be punched or cut from a plate.

[0017] In a further advantageous form of the cell connector, it is contemplated that the web has at least one perforation. In particular, the web is substantially Strip-shaped having a thickness smaller than that of the element in the thickness direction and / or the web is corrugated in the width direction. Thereby, the height deviation of the galvanic cells arranged side by side and connected by the cell connector of the present invention is compensated more easily. By the perforations introduced into the web, the individual substantially Strip-shaped elements can be easily relatively moved in the thickness direction. The corresponding rigidity of the web can be further reduced by reducing the thickness of the web in the thickness direction. The cross-sectional shape of the web when viewed in the longitudinal direction can also have the corresponding profile. For example, the cross-section can be made corrugated in order to more easily compensate for the height deviation between the individual substantially strip-shaped elements of the cell connector in the thickness direction.

[0018] Corresponding to a further advantageous form of the cell connector, at least one substantially Strip-shaped element has a connection flange that extends in the longitudinal direction and extends away from the second and / or fourth section in the width direction, and substantially Strip-shaped is arranged on the energizing component arranged overlapping the element and substantially Strip-shapedIt is provided for making contact connections between components. Using this connection flange, the cell connector of the present invention can be easily contact-connected to, for example, a current contact rail. Thereby, it is further possible to circuit-connect a plurality of battery modules or cell blocks to each other particularly easily. Here, the connection flange can have a shape that is specially adapted to a specific installation situation or geometric situation, similar to the first or fifth section. For example, in order to be able to screw the connection flange to the current contact rail, one or more through-holes can be introduced into the connection flange. Here, the current can flow through a screw that is passed through the through-hole and through-guided. Generally, it is conceivable that a connection by any form fit, friction fit, and / or material bond is established between at least one connection flange and at least one energized component arranged in an overlapping manner. For example, the connection flange can also be welded or riveted to the current contact rail. Advantageously, the connection flange is substantially one of a plurality included in the cell connector Strip-shaped among the components, and is substantially one at the edge Strip-shaped included in the component.

[0019] In a further advantageous form of the cell connector, in order to increase the pressing force of the first and second clamping surfaces acting in the thickness direction on the conductor and / or litz wire arranged in the accommodating part, at least one substantially Strip-shapedIn the folded state of the element, it is contemplated that the second section is at least partially curved in the thickness direction and / or at least one half of the closure element has a contour extending in the thickness direction when the closure element is connected. Preferably, the conductors and / or litz wires to be connected are pressed against each other with a relatively large pressing force in order to fix them to each other particularly securely. Due to the curvature of the second section, this pressing force is increased by the spring action of the second section resulting from the curvature. Here, the entire second section may be curved or may have at least partially individual curvatures. The individual curvatures can have the same radius of curvature or different radii of curvature. In addition to or instead of the curvature of the second section, one or both halves of the closure element can also have a contour extending in the thickness direction. These can have any cross-sectional shape. For example, this can be a conical or pyramidal tip. At least one half of the closure element can also be partially corrugated in the thickness direction. Due to the contour, the first and second sections need to be further folded around the folding axis until the first and fifth sections can be closed. Thereby, the distance between the first clamping surface and the second clamping surface is reduced in the thickness direction, thereby increasing the pressing force on the conductors and / or litz wires present in the receiving portion.

[0020] Preferably, at least one substantially Strip-shaped The element is completely formed from a conductive material, in particular a metal and / or metal alloy, preferably from a metal sheet, or at least one substantially Strip-shaped The element is at least partially formed from a conductive material, in particular a metal or metal alloy, preferably a metal sheet, and at least partially from a current insulating material, and the insulating material preferably forms at least the fourth section. At least one substantially Strip-shaped When the element contains a conductive material, the current between the plurality of conductors and / or litz wires to be connected can at least partially flow through at least one substantially strip-shaped element. Thus, at least two Strip-shaped Elements can be used to realize, for example, a particularly simple parallel connection of a plurality of galvanic cells. At least one substantiallyStrip-shaped If the element contains a metal or a metal alloy, for example, the second section can also be welded and incorporated into a materially bonded weld connection of the conductor and / or the litz wire to be connected.

[0021] If the cell connector consists of at least two substantially Strip-shaped elements, the first substantially Strip-shaped element includes a first and a second section, and the second substantially Strip-shaped element may include a fourth and a fifth section. In this case, the first substantially Strip-shaped element is made entirely of a metal alloy, and the second substantially Strip-shaped element is made of an insulating material. If the fourth section, i.e., the second clamping surface, contains an insulating material, this material can function as a weld bead support. On the other hand, if the fourth section also contains a metal or a metallic material, it can also be welded, which ensures a highly reliable contact connection of the conductor and / or the litz wire.

[0022] Generally, it is also conceivable that the entire cell connector is made of an insulating material.

[0023] In a method of making a contact connection between at least two galvanic cells using at least one of the aforementioned cell connectors, according to the invention, at least the following method steps, namely, · a step of mutually adjusting the conductors and / or litz wires to be connected; · a step of arranging the cell connector with respect to the conductors and / or litz wires such that the fourth section is supported at least partially on the cover of at least one galvanic cell on the side opposite to the receiving part and / or at least one conductor and / or at least one litz wire is placed on the side of the fourth section facing the receiving part; · Strip-shaped a step of folding the first and second sections about a folding axis extending in the width direction through the third section to bring the element into a folded state; · a step of closing the closing element; ·Welding the conductor and / or litz wire to be connected, or welding at least a part of the cell connector to the conductor and / or litz wire to be connected, in particular by means of at least one welding seam extending in the longitudinal direction, and preferably using laser welding as the welding method; is carried out.

[0024] Here, the conductor and / or litz wire to be connected are mutually adjusted so that they contact or overlap with as large an area as possible in order to enable a low-resistance contact connection of the galvanic cell to be connected. The conductor and / or litz wire to be connected are fixed in this state using the cell connector of the present invention. For this purpose, the cell connector of the present invention is guided and closed around the conductor and / or litz wire to be connected, like a clamp. Here, optionally, the cell connector of the present invention can be supported on at least one galvanic cell or on the cover of a battery module and / or battery housing containing a galvanic cell. Preferably, at least one conductor and / or at least one litz wire are placed flat on at least one of the clamping surfaces. Thereby, a pressing force is applied, in particular evenly, to the conductor and / or litz wire to be connected. The closing of the closing element is performed by any form fit, friction fit and / or material bond. For example, individual parts of the half of the closing element, such as tabs or protrusions, can be folded, crimped, wound up, etc., and thereby introduced or received, for example, from an opening or receiving part into the corresponding mating half of the closing element. The closed closing element can be additionally fixed by riveting, screwing, welding, soldering, adhesion, etc. Subsequently, the galvanic cell to be contact-connected can be safely transported without the conductor and / or litz wire to be connected shifting or slipping during transportation. This is because the pressing force applied to the conductor and / or litz wire by the cell connector of the present invention prevents this. Next, the conductor and / or litz wire to be connected are welded. For this purpose, any welding method, preferably laser welding, can be used. Since the conductor and / or litz wire are pressed by the cell connector of the present invention, it is possible to form a particularly reliable welded connection.

[0025] Further advantageous forms of the cell connector of the present invention and of the method of the present invention can also be obtained from the embodiments described in detail below with reference to the figures.

Brief Description of the Drawings

[0026]

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Embodiments for Carrying Out the Invention

[0027] FIG. 1 is used to explain the problems when a plurality of so-called pouch cells 19 are circuit-connected to each other in the prior art. Here, FIG. 1a) shows the problems when the pouch cells 19 are circuit-connected in series with each other, and FIG. 1b) shows the problems when a plurality of pouch cells 19 are circuit-connected to each other according to a parallel connection. In order to connect at least two pouch cells 19 in series with each other, a large number of conductors 2, often made of copper or aluminum, drawn out from the pouch cells 19, are welded to each other. For this purpose, advantageously, the conductors 2 to be connected come into contact flatly along as large an area as possible. Due to the bending error and / or component tolerance during the mutual adjustment of the conductors 2 to be connected, the conductors 2 to be connected do not extend parallel to each other but obliquely to each other, whereby they do not come into contact with each other flatly but only pointwise along one line, let alone in a continuous manner. In this case, it is not possible to form the continuous welding seam 18 shown in FIG. 11 for the connection of the two conductors 2, or a defective welding seam 18 is formed.

[0028] To compensate for such bending errors or component tolerances, the conductors 2 to be connected are pressed against each other by applying a pressing force F by a pressing tool 20. This is shown on the right side of FIG. 1a). Thereby, the conductors 2 become flat with each other and can be reliably welded. Here, typically, at least one cover 17 of the pouch cells 19 is used as a support. This cover 17 may be, for example, one of the cell frames of the pouch cells 19 or a battery module housing or the like. The drawback here is that the bending error cannot be completely compensated, so that the gap between the conductors 2 to be connected cannot be made zero. Furthermore, the corresponding pressing tool 20 has to be adjusted laboriously.

[0029] A further problem is to connect a plurality of pouch cells 19 to form a parallel connection. For this purpose, typically, cell connectors 21 known from the prior art are used. If the pouch cells 19 connected in parallel, or their covers 17, or the self-frames of the pouch cells 19 have a height deviation from each other, this may cause the cell connector 21 to abut obliquely against the conductor 2 to be connected. Similarly, a gap is generated thereby, so that the cell connector 21 cannot be welded flatly to the conductor 2 to be connected. To compensate for this height difference, cell connectors 21 having a curved portion are known. This is shown on the right of FIG. 1b). However, here, in the welding process, a relatively high requirement is imposed on the positioning of the components to be connected as accurately as possible. When connecting more than two pouch cells 19 in parallel, this problem may become more serious.

[0030] By using the cell connector 1 shown in FIG. 2, the pouch cells 19 to be connected or in contact connection can be particularly reliably connected in contact by welding. The cell connector 1 of the present invention includes at least one substantially Strip-shaped element 4. This includes five sections 4.1, 4.2, 4.3, 4.4, 4.5, which are arranged continuously in the longitudinal direction L and substantially Strip-shaped on the element 4. Substantially Strip-shaped The element 4 has a small size in the thickness direction D orthogonal to the longitudinal direction L and the width direction B orthogonal to the longitudinal direction L, compared to the size in the longitudinal direction L and the size in the width direction B. The first section 4.1 and the fifth section 4.5 each form a half of the closing elements 5.1 and 5.2. The second section 4.2 forms the first clamping surface 6.1, and the fourth section 4.4 forms the second clamping surface 6.2. The third section 4.3 forms a bending element 7. A folding axis 8 extends in the width direction B through the bending element 7. Substantially Strip-shaped The element 4 can be folded or closed around the folding axis 8. Substantially Strip-shapedTo enable relatively easy bending or folding around the folding axis 8 of the element 4, the bending stiffness of the bending element 7 is reduced by applying perforations 10 to the bending element 7 or the third section 4.3. Here, the perforations 10 can be formed by rectangular cutouts as shown in FIG. 2. However, the perforations 10 can have any shape. In addition to or instead of the perforations 10, the bending element 7 can include or be formed by a hinge 11. This is shown in detail in FIG. A. When the hinge 11 forms the third section 4.3, the cell connector 1 of the present invention is composed of at least two substantially Strip-shaped constituted by the element 4. In this case, each substantially Strip-shaped element 4 can also be made of the same or different materials. For example, substantially Strip-shaped one of the elements 4 can be made of a conductive material M as shown in FIG. 11, and the other substantially Strip-shaped element 4 can be made of a current-insulating material I. However, generally, the entire cell connector 1 can be made only from the conductive material M or only from the insulating material I. The cell connector 1 can also be made of a conductive material. In this case, substantially Strip-shaped one of the elements 4 is made of a first conductive material M, for example aluminum, and the second substantially Strip-shaped element 4 is made of another conductive material M, for example copper. FIG. 2 shows a further detailed view A, where instead of the hinge 11, an elastic material 12 for forming the third section 4.3 is shown. In this case, this can be, for example, an elastomer. However, any elastic material, such as rubber, natural rubber, silicone, etc., can be considered for forming the third section 4.3. In particular, the third section 4.3 or the bending element 7 can also be at least partially perforated. Thereby, the bending resistance around the folding axis 8 or around the longitudinal direction L can be appropriately adjusted. The third section 4.3 can also have a conductive material M, especially in the form of a film hinge.

[0031] The first section 4.1 and the fifth section 4.5 or the respective halves 5.1 and 5.2 of the closure element here have geometric shapes that match each other. In the example of Figure 2, the first section 4.1 forms a tab and the fifth section 4.5 forms a pocket for receiving the tab. Approximately Strip-shaped When the element 4 is bent around the folding axis 8, the respective halves 5.1 and 5.2 of the closure element are mutually adjusted so that they can form a shape connection. To fix the shape connection, the respective closure element halves 5.2 and 5.2 can be joined by additional frictional connection and / or material connection.

[0032] Figure 3 shows a plan view of the cell connector 1 according to an alternative embodiment. Here, a substantially rectangular notch for forming a welding window 13 is provided in the second section 4.2 or the first clamping surface 6.1. However, the welding window 13 can also have any shape different from a rectangle. Through the welding window 13, the accessibility of the welding tool to the conductor 2 and / or the litz wire 3 surrounded by the cell connector 1 is improved, as shown in Figures 10 and 11.

[0033] Figure 4 shows a plan view of the cell connector 1 of the present invention comprising a plurality of substantially Strip-shaped elements 4. Here, a plurality of substantially Strip-shaped elements 4 are connected to each other via one web 14 each. In the example of Figure 4, the webs 14 are each connected to the second section 4.2 of the substantially Strip-shaped element 4. Here, one or more of the substantially Strip-shaped elements 4 can also have a welding window 13. In this case, it is not necessarily required that all the bending elements 7 of the substantially Strip-shaped element 4 are configured identically. Thus, any number of substantially Strip-shaped elements 4 can have, for example, perforations 10, hinges 11 and / or elastic material 12 for forming the bending elements 7. However, generally, at least one web 14 is substantially Strip-shapedIt is also conceivable that it is at least partially connected to a fourth section 4.4 of one of the elements 4. Using the cell connector 1 shown in FIG. 4, a plurality of galvanic cells or pouch cells 19 can be circuit-connected to each other in parallel particularly simply.

[0034] In the closed or folded state approximately Strip-shaped The element 4 surrounds the two conductors 2 and / or the litz wire 3 to be connected. In doing so approximately Strip-shaped The element 4 exerts a pressing force F on the component to be connected. In order to increase this pressing force F, as shown in FIG. 5, approximately Strip-shaped At least one region of any one section of the element 4 can be curved. In the example of FIG. 5, the entire second section 4.2 is curved around the width direction B. The resulting elastic action can increase the pressing force F. Approximately Strip-shaped It is also conceivable that a plurality of sections 4.1 to 4.5 of the element 4 are curved or have a region that is only partially curved.

[0035] It is also possible to increase the pressing force F by profiling the first and / or second halves 5.1 and 5.2 of the closing element. For this purpose, FIG. 6 shows a detailed view of the cross-section B-B shown in FIG. 5. Here, the profile 22 can have any shape. For example, the profile 22 can be formed by a conical or pyramidal stub protruding in the thickness direction D. The closing element half 5.1 or the closing element half 5.2 can also have a wavy cross-section in the width direction B.

[0036] FIG. 7 shows a plan view of the cell connector 1 of the present invention having a plurality of approximately Strip-shaped elements 4 according to an alternative embodiment. In the example of FIG. 7, the perforation 15 is provided in the web 14 connecting the two approximately Strip-shaped elements 4. The perforation 15 reduces the bending stiffness of the web 14 around the longitudinal direction L. Thereby, the height deviation in the thickness direction D when connecting two pouch cells 19 in parallel can be compensated more easily. Here too, the perforation 15 can have any cross-sectional shape. Preferably, the perforation 15 has a rectangular shape.

[0037] Figure 8 shows a detailed view of cross-section C-C shown in Figure 7. By reducing the material strength at the material part of the web 14, the bending rigidity of the web 14 can be appropriately adjusted to a desired value. The web 14 can also have a specific cross-sectional shape in the width direction B, for example, a corrugated cross-sectional shape.

[0038] Figure 9 shows a plan view of the cell connector 1 of the present invention according to a further alternative embodiment. In the example of Figure 9, substantially Strip-shaped Element 4 has a connection flange 16, and this connection flange extends away from the second section 4.2 and / or the fourth section 4.4 in the width direction B. By using the connection flange 16, substantially Strip-shaped it is possible to easily and reliably make a contact connection between element 4 and an energized component disposed thereon, such as a current contact rail or a conductor of a battery module. Here, the connection flange 16 can be connected to the energized component disposed thereon in any form and manner by form fit, friction fit, and / or material bond. In the example of Figure 9, substantially Strip-shaped two through holes are introduced into the connection flange 16 to connect element 4 to an energized element disposed thereon by screw connection. When a metal screw is used, it is possible to conduct electricity through the screw. However, the connection flange 16 can also be welded, brazed, or riveted to the energized component disposed thereon. For example, corresponding structural changes can also be made in the connection flange 16 to insert it into the energized component disposed thereon.

[0039] Figure 10 shows a principle diagram of the method 100 of the present invention for making a contact connection between at least two galvanic cells, for example, two pouch cells 19. In method step 101, the conductors 2 and / or litz wires 3 (not shown here) to be connected are mutually adjusted so that they overlap as flat as possible, thereby forming a particularly reliable welding seam 18. In method step 102, it is also possible to optionally bend in advance, substantially Strip-shapedThe cell connector 1 of the present invention consisting of element 4 is pushed between the conductor 2 to be connected and the cover 17 of the pouch cell 19 or the frame of the battery module. In method step 103, at least one substantially Strip-shaped Element 4 is folded around the folding axis 8, whereby the first and second clamping surfaces 6.1 and 6.2 are flatly placed on the conductor 2 or the litz wire 3 to be connected and pressed against each other by the pressing force F. At that time, at least one substantially Strip-shaped Element 4 forms a receiving portion 9 for receiving the component to be connected. In the folded state, the first half 5.1 of the closing element and the second half 5.2 of the closing element are connected to prevent at least one substantially Strip-shaped Element 4 from opening undesirably. Next, the pouch cell 19 to be in contact connection is transported to the welding device. Thanks to the closed cell connector 1, the fixed components to be in contact connection, namely the conductor 2 and / or the litz wire 3, cannot move relative to each other. In method step 104, the conductor 2 and / or the litz wire 3 are welded. For this purpose, laser welding is preferably used.

[0040] Figure 11 shows various cross-sectional views of cross-section D-D shown in Figure 10. Depending on the embodiment of the cell connector 1 used, four different welding seams 18 occur. Here, Figures 11a) and b) show the welding seam 18 by the cell connector 1 without the welding window 13, and Figures 11c) and d) show the welding seam 18 when using the cell connector 1 with the welding window 13. Furthermore, Figures 11a) and c) show the application of the conductive material M for forming the fourth section 4.4 or the second clamping surface 6.2. Thus, the welding seam 18 can extend so as to enter the second clamping surface 6.2. According to Figures 11b) and d), this is not possible because the fourth section 4.4 or the second clamping surface 6.2 is formed from the current insulating material I. Thereby, the cell connector 1 can function as a welding bead support. On the other hand, when the welding seam 18 enters into the fourth section 4.4, a particularly process-reliable contact connection of the conductor 2 and / or the litz wire 3 to be connected can be ensured. In the example of Figures 11a) and b), the welding seam 18 can also be appropriately alloyed by welding the second section 4.2. Generally, in the embodiment of Figure 11d), it is also possible that the entire cell connector 1 consists of the current insulating material I. Nevertheless, the welding window 13 ensures the weldability of the conductor 2 and / or the litz wire 3 to be connected.

[0041] Figure 12 shows a side view of a laser welding process for contact-connecting two electrical cables by means of the cell connector 1 of the present invention. Figure 12 is used to explain that instead of at least one conductor 2, one or more litz wires 3 of one or more conductive cables can also be fixed according to one of the above-described embodiments in order to enable them to be welded particularly reliably.

Claims

1. A cell connector (1) for connecting at least two conductors (2) and / or litz wires (3) to each other, consisting of at least one strip-shaped element (4), characterized by at least five sections (4.1, 4.2, 4.3, 4.4, 4.5) arranged continuously in the longitudinal direction (L) of the strip-shaped element (4), wherein the first section (4.1) forms the first half (5.1) of the closing element, the second section (4.2) forms the first clamping surface (6.1), the third section forms the bending element (7), the fourth section (4.4) forms the second clamping surface (6.2), the fifth section (4.5) forms the second half (5.2) of the closing element, and the third section (4.3) is configured such that the first section (4.1) and the second section (4.2) can be folded around a folding axis (8) extending through the third section (4.3) in a width direction (B) orthogonal to the longitudinal direction (L) with respect to the fourth section (4.4) and the fifth section (4.5). As a result, in the folded state of the strip-shaped element (4), at least a part of the first clamping surface (6.1) and the second clamping surface (6.2) are substantially opposed in a thickness direction (D) extending orthogonal to the longitudinal direction (L) and the width direction (B), thereby forming a receiving portion (9) for the conductor (2) and / or the litz wire (3), and the first section (4.1) and the fifth section (4.5) are connectable to each other to fix the at least one strip-shaped element (4) in the folded state, The cell connector (1), wherein at least two strip-shaped elements (4) arranged parallel to each other in the longitudinal direction (L) extend away from the strip-shaped element (4) in the width direction (B) from the second section (4.2) and / or the fourth section (4.4) and are connected via at least one web (14) extending in the longitudinal direction (L).

2. The cell connector (1) according to claim 1, characterized in that the third section (4.3) comprises at least one perforation (10), hinge (11) and / or elastic material (12) and / or is at least partially contoured.

3. The first section (4.1) and the fifth section (4.5) are designed to be shape - joined, in particular, by bending, beading, rounding, or caulking at least one of these sections (4.1, 4.5), and / or The first section (4.1) and the fifth section (4.5) are designed to be friction - joined and / or material - joined, in particular, by riveting, screwing, welding, and / or gluing these sections (4.1, 4.5). The cell connector (1) according to claim 1 or 2 is characterized by this.

4. The second section (4.2) has a notch, in particular a substantially rectangular notch, for forming a welding window (13) that extends through the second section (4.2) in the thickness direction (D). The long side of the notch extends in the longitudinal direction (L). The cell connector (1) according to claim 1 or 2 is characterized by this.

5. The web (14) has at least one perforation (15). In particular, the web (14) has a thickness smaller than that of the strip - shaped element (4) in the thickness direction (D), and / or the web (14) is corrugated in the width direction (B). The cell connector (1) according to claim 1 or 2 is characterized by this.

6. At least one strip - shaped element (4) has a connection flange (16) that extends in the longitudinal direction (L) and extends away from the second section (4.2) and / or the fourth section (4.4) in the width direction (B). It is used to make a contact connection between the strip - shaped element (4) and an energizing component disposed on the strip - shaped element (4). The cell connector (1) according to claim 1 or 2 is characterized by this.

7. In order to increase the pressing force (F) of the first clamping surface (6.1) and the second clamping surface (6.2) acting in the thickness direction (D) on the conductor (2) and / or the litz wire (3) disposed in the accommodating part (9), when the at least one strip - shaped element (4) is in a folded state, the second section (4.2) is at least partially curved in the thickness direction (D), and / or at least one half (5.1, 5.2) of the closing element has a contour portion (22) that extends in the thickness direction (D) when the closing element is connected. The cell connector (1) according to claim 1 or 2 is characterized by this.

8. The at least one strip-shaped element (4) is completely formed from a conductive material (M), in particular a metal or a metal alloy, preferably a metal sheet, or the at least one strip-shaped element (4) is at least partially formed from a conductive material (M), in particular a metal or a metal alloy, preferably a metal sheet, and at least partially from a current-insulating material (I), and the insulating material (I) advantageously forms at least the fourth section (4.4). The cell connector (1) according to claim 1 or 2, characterized in that.

9. A method of contact-connecting at least two galvanic cells using at least one cell connector (1) according to claim 1 or 2, At least the following method steps, namely - Adjusting the conductors (2) and / or litz wires (3) to be connected to each other; - The fourth section (4.4) is at least partially on the side (S １ opposite to the receiving part (9), supported on the cover (17) of at least one galvanic cell, and / or at least one conductor (2) and / or at least one litz wire (3) is on the side (S ２ ) of the fourth section (4.4) facing the receiving part (9), arranging the cell connector (1) relative to the conductor (2) and / or the litz wire (3) such that the conductor (2) and / or the litz wire (3) is placed thereon; - Folding the first section (4.1) and the second section (4.2) through the third section (4.3) by means of the folding axis (8) extending in the width direction (B) to bring the strip-shaped element (4) into a folded state; - Closing the closing element; - Welding the conductors (2) and / or litz wires (3) to be connected, or welding at least part of the cell connector (1) to the conductors (2) and / or litz wires (3) to be connected, in particular by means of at least one welding seam (18) extending in the longitudinal direction (L), and preferably laser welding being used as the welding method; The method, characterized by the above.

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