Contact element

Abstract

Contact element for electrically contacting at least one battery cell, wherein the contact element (8, 17, 18) comprises at least one lamella (8), wherein the lamella (8) has at least one first opening (11) and at least one bendable tab (12) of the first opening (11), wherein the tab (12) of the first opening (11) projects from an edge of the first opening (11) into the first opening (11) and covers a first partial area of ​​the first opening (11), wherein an electrical contact designed as a pin (6, 7, 21) can be inserted into the first opening (11), wherein a pin (6, 7, 21) inserted into the first opening (11) can be clamped by means of the at least one bendable tab (12), characterized in that the contact element (8, 17, 18) comprises a first and at least one further lamella (8), wherein an underside of the at least one further Slat (8) is arranged above an upper side of the first slat (8).

Description

[0001] The invention relates to a contact element for electrically contacting at least one battery cell.

[0002] In motor vehicles, especially electric or hybrid vehicles, battery cells are used to store electrical energy. The electrical energy from these battery cells is used to supply power to, for example, control units or an electric motor to power the vehicle.

[0003] Typically, many battery cells are combined into a so-called battery block. Several such battery blocks can be arranged in the vehicle. It is known to connect battery cells within the battery blocks in parallel or in series. For this purpose, the positive and negative terminals of each battery cell in a battery block are connected in a suitable manner using so-called battery cell connectors or contact elements. These battery cell connectors also serve to establish electrical contact between battery cells in different battery blocks, for example, to connect two battery blocks in series.

[0004] DE 20 2009 012 647 U1 discloses a battery cell connector with a first connection part formed for connection to a battery pole of a first battery, a second connection part, and a connecting part arranged between the connection parts and electrically contacting the connection parts with one another. The first connection part is formed from a first electrically conductive material at least on the side facing a battery pole. Furthermore, a flat piece formed for connection to a second battery pole is arranged in a materially bonded manner on the second connection part and is formed from a second electrically conductive material different from the first electrically conductive material at least on the side facing the second battery pole. Furthermore, at least one connection part is formed from annealed aluminum.

[0005] Battery cell connectors are also known, which are designed in the form of metal brackets and are plugged onto the poles of the individual battery cells.

[0006] US 2,901,526 A and US 4,024,953 A each disclose generic contact elements for electrically contacting at least one battery cell.

[0007] The technical problem is to create a contact element for electrically contacting at least one battery cell, which enables simple, even automated, assembly and at the same time high assembly flexibility, high-quality contact and compensation of assembly tolerances.

[0008] The solution to the technical problem results from the subject matter having the features of claim 1. Further advantageous embodiments of the invention result from the subclaims.

[0009] A contact element is proposed for making electrical contact with at least one battery cell. The battery cell can have at least one positive pole and at least one negative pole. The contact element for making electrical contact can also be referred to as a battery cell connector or pole connector. The contact element is used for the electrical connection or interconnection of battery cells, in particular battery cells of a battery block, the battery block comprising a plurality of battery cells. In particular, the contact element is used for connecting a plurality of battery cells in series. For this purpose, for example, a positive pole of a first battery cell is electrically connected to a negative pole of a second battery cell by means of the contact element. Furthermore, a positive pole of the second battery cell is electrically connected to a negative pole of a third battery cell by means of a further contact element according to the invention.The contact element can also be used to electrically connect a battery cell of a first battery block to a battery cell of a further battery block. For example, a positive terminal of a battery cell of the first battery block is electrically connected to a negative terminal of a battery cell of the further battery block by means of the contact element. This allows multiple battery blocks to be connected in series. By appropriate wiring, battery cells and / or battery blocks can also be connected in parallel.

[0010] The contact element comprises at least one lamella. A lamella is understood here to be a preferably thin plate made of electrically conductive material, for example a metal sheet. The lamella has a top and a bottom side. The lamella can, for example, be rectangular. In particular, it can have two long sides with a predetermined length and two end faces with a predetermined width, wherein the length is preferably greater than the width. This results in a rectangular shape of the lamella. Other shapes of the lamella are of course also conceivable. It is important that the dimensions of the lamella are adapted to the arrangement of the battery cells to be connected. For example, the length of the lamella must be at least as great as the distance between two poles of two battery cells to be electrically connected.

[0011] The slat has at least one first opening and at least one bendable tab of the first opening. The bendable tab can be formed, for example, by the slat itself. However, it is also possible to attach the bendable tab to the slat using a suitable connection technology. The tab of the first opening projects from an edge of the first opening into the first opening. The tab of the first opening covers a first partial area of ​​the first opening. In an unbent or non-erected state, the at least one tab projects into the first opening, wherein the first tab is arranged or lies in a slat plane in this initial state. The at least one tab does not cover the entire first opening, resulting in a covered first partial area and an uncovered second partial area of ​​the opening. The tab thus reduces the opening area of ​​the first opening.

[0012] An electrical contact in the form of a pin can be inserted into the first opening. The pin can be cuboid-shaped, cylindrical, or a combination of the two. The pin can be a positive or negative terminal of a battery cell. The pin can also be any electrical connector.

[0013] Furthermore, a pin inserted into the first opening can be clamped by means of the at least one flexible tab and thus releasably mechanically connected to the slat. For this purpose, the size of the first opening and the dimensions and shape of the at least one flexible tab are adapted to the size of the pin. In particular, the first opening is larger than the outer diameter of the part of the pin to be clamped in the first opening.

[0014] For example, at least one outer diameter of the pin or of the part of the pin to be clamped can be smaller than a distance between an end face of the at least one flexible tab and an edge of the first opening opposite the end face or an end face of another flexible tab opposite the end face.

[0015] It is also conceivable for the size of a surface area of ​​a second partial region of the first opening to be smaller than a cross-sectional area of ​​the pin. The cross-sectional area of ​​the pin refers to the area of ​​a cross section when the pin is cut in a plane perpendicular to the insertion direction of the pin. It should be noted that the second partial region of the first opening is the portion of the first opening not covered by the at least one tab of the first opening.

[0016] Thus, if the pin is inserted into the first opening or the slat with the first opening is placed onto the pin, the at least one tab of the first opening bends elastically out of the slat plane of the slat. Preferably, the at least one flexible tab of the first opening is designed to be resilient for this purpose, with a spring force of the flexible tab counteracting a change in the position of the flexible tab from its initial position. Inserting the pin into the first opening or placing the slat onto the pin can also be referred to as linear joining.

[0017] The contact element according to the invention advantageously enables clamping of the pin by means of the flexible, preferably spring-elastic, tab. This allows a defined contact force to be exerted on the pin. In addition, by dimensioning the flexible tab, in particular the parts of the flexible tab that rest against the pin in the clamped state, a predetermined electrical contact resistance can be created between the pin and the lamella. Preferably, the lamella has several tabs that project into the first opening. This advantageously enables clamping of the at least one pin on several sides. The linear joining of the pin and lamella described in this way can be easily automated, so that, for example, battery cells arranged in battery blocks can be easily connected in series or parallel in an automated manner.

[0018] Preferably, the first opening is arranged on an end face of the slat.

[0019] The contact element further comprises a first and at least one further lamella, wherein an underside of the at least one further lamella is arranged above an upper side of the first lamella. In this case, a layering of several lamellas is carried out in order to produce a contact element according to the invention. In this case, for example, the previously explained spacer elements, which are arranged on an upper and / or lower side of a lamella, enable the flexible tabs to continue to stand up when a pin is inserted, even in a layered arrangement of lamellas. A plurality of lamellas advantageously results in a greater current carrying capacity of the contact element. The contact element in this case therefore consists of a first number of layered lamellas, wherein the first number depends on a predetermined or desired current carrying capacity, i.e. a level of current to be conducted through the contact element.This advantageously results in the contact element being modular in design and adaptable to various desired current carrying capacities.

[0020] In one embodiment, the at least first opening is rectangular. In this case, edges of the rectangular opening can run parallel to the long sides and end sides of a rectangular slat. In a special embodiment, the first opening is square. Of course, other shapes of the first opening are also conceivable; in particular, the shape of the first opening can be adapted to the geometry of the pin to be inserted into the shape. With a rectangular first opening, this advantageously results in simple production of the rectangular opening, for example by punching, and electrical and mechanical contact with a pin to be inserted by means of four tabs, if bendable tabs are arranged on all four sides of the rectangular opening.

[0021] In a preferred embodiment, the first opening has four tabs, each of which extends from one of the four edges of the first opening into the first opening. As previously described, this provides the advantage that a pin inserted into the first opening can be clamped from four sides. Recesses can be arranged between the bendable, preferably additionally spring-elastic, tabs so that the four tabs can be bent out of the slat plane independently of one another.

[0022] In a further embodiment, the at least one slat has at least one spacer element on a top and / or bottom side of the slat, wherein the at least one spacer element is raised above the top and / or bottom side. This advantageously results in the ability to stack multiple slats one on top of the other. The spacer elements ensure that slats arranged one on top of the other are spaced apart from one another in such a way that the flexible tabs of the first opening can continue to extend out of the slat plane when a pin is inserted, without being hindered in doing so by another slat arranged above the slat.

[0023] In a further embodiment, the slat has at least one further opening and at least one bendable tab of the further opening. The tab of the further opening is also preferably designed to be spring-elastic. The tab of the further opening projects from an edge of the further opening into the further opening and covers a first partial area of ​​the further opening. An electrical contact designed as a pin can also be inserted into the further opening, wherein a pin inserted into the further opening can be clamped by means of the at least one bendable tab of the further opening. The slat can therefore also be detachably mechanically connected to a further pin. The second partial area of ​​the further opening is the part of the first opening not covered by the at least one tab of the further opening. In this embodiment, the slat therefore has two openings.In this case, the first opening can, for example, be inserted over a positive pole, designed as a pin, of a first battery cell, wherein the second opening can be inserted over a negative pole, designed as a pin, of a second battery cell. With regard to the mechanical and electrical connection of a pin to the lamination by means of the at least one further opening, the same properties arise, in particular with regard to a predetermined contact force and a predetermined contact resistance, as when contacting a pin using the first opening of the lamination. Of course, poles of battery cells in different battery blocks can also be electrically connected by means of a lamination designed in this way. This advantageously results in poles of different battery cells being able to be electrically connected to one another in a simple manner by linearly joining or plugging on the lamination.As previously mentioned, such linear joining can be easily implemented in an automated manner.

[0024] In a further embodiment, the further opening is rectangular and has two tabs. The tabs protrude from opposite edges of the further opening into the further opening. As a result, a pin inserted into the further opening is only electrically and mechanically contacted from two sides by means of the two tabs. Thus, a pin inserted into the further opening can be moved in a direction parallel to the opposite edges having the tabs. If, for example, a pole of a first battery cell is connected to a pole of a second battery cell by means of this contact element, this advantageously results in a relative movement between the pole of the first battery cell and the pole of the second battery cell even in the connected state, without an electrical connection being interrupted. Thus, for example,Small relative changes in connected poles caused by vibrations during driving can occur without an electrical connection being interrupted.

[0025] In a preferred embodiment, the tabs protrude from opposite edges of the further opening into the further opening, wherein the edges are arranged parallel to a longitudinal direction of the slat. Preferably, the further opening is designed as an elongated hole, wherein the edges of the further opening arranged parallel to a longitudinal side of the slat have a greater length than the edges of the further opening parallel to, for example, an end face of the slat. The edges of the further opening arranged parallel to a longitudinal side of the slat can also have a greater length than the edges of the first opening parallel to the longitudinal side of the slat. Thus, a pin inserted into the further opening can be displaced in the longitudinal direction of the slat. As described above, this allows, for example,enables a relative movement between a pole designed as a pin of a first battery cell and a pole designed as a pin of a second battery cell, wherein the poles are electrically and mechanically connected by means of the lamella. Furthermore, the inventive design of the further opening results in tolerances in the arrangement of battery cells to be connected within a battery pack and tolerances in the manufacture of the lamella can be compensated for in a simplified manner. Furthermore, a certain variability of distances results between two battery poles designed as pins to be connected by means of the lamella, whereby the lamella is suitable for, for example, different pin geometries or for connecting battery cells of adjacent battery blocks.

[0026] A layering of slats can be achieved in two alternatives. In a first alternative, a center line of the first opening of the first slat, running perpendicular to the top side of the first slat, is aligned with a center line of the first opening of the at least one further slat, running perpendicular to the top side of the at least one further slat. Furthermore, a center line of the further opening of the first slat, running perpendicular to the top side of the first slat, can be aligned with a center line of the further opening of the at least one further slat, running perpendicular to the top side of the at least one further slat.

[0027] In a second preferred alternative, a center line of the first opening of the first slat, running perpendicular to the top side of the first slat, is aligned with a center line of the further opening of the at least one further slat, running perpendicular to the top side of the at least one further slat. Furthermore, a center line of the further opening of the first slat, running perpendicular to the top side of the first slat, can be aligned with a center line of the first opening of the at least one further slat, running perpendicular to the top side of the at least one further slat.

[0028] In the first alternative, all the first openings of the stacked lamellae are arranged one above the other, with the first openings being aligned. A pin can therefore be inserted into the first openings of all lamellae. Preferably, all lamellae are of identical design. If the lamellae are arranged parallel in their longitudinal direction and are of identical design, then in this case all the other openings of the lamellae are also arranged one above the other. This results in the advantages previously described for a lamella with regard to compensating for manufacturing and arrangement tolerances, whereby the desired current-carrying capacity of the contact element can be ensured by layering several lamellae.

[0029] In the second alternative, the further opening of the further lamella is arranged above the first opening of the first lamella. In this case, a first opening of the further lamella is arranged above a further opening in the first lamella. If the lamellas are arranged parallel in their longitudinal direction and the openings are arranged accordingly in the lamellas, then in this case a further opening of the further lamellas is also arranged above a first opening in the first lamella. This results in what is known as alternating layering of lamellas. This alternating layering likewise ensures relative movement between two pins that are electrically and mechanically connected by the lamellas. In an advantageous manner, however, better contact with regard to an electrical and mechanical connection can be achieved by, for example, four tabs alternately on the pins to be connected.This advantageously results in a balanced distribution of contact force and contact resistance between the two pins to be connected.

[0030] The layered structure also makes it possible to accommodate relative movement solely through the contact element's design of individual lamellas. The contact elements can be layered individually or pre-assembled using suitable connection technology and / or integrated into circuit boards and support structures.

[0031] For contacting across multiple levels, a pin can be combined with two coaxially layered contacts at any distance.

[0032] In a further embodiment, the contact element comprises a lamella or at least two stacked lamellas, each having a first opening, wherein each lamella has an electrical interface to an electrical conductor embodied as a mechanically flexible cable. Furthermore, the contact element comprises this electrical conductor embodied as a flexible cable. By means of a contact element embodied in this way, for example, a battery terminal embodied as a pin can be contacted with another electrical contact that cannot be contacted via a further opening in the lamella. In this way, larger distances between two pins to be connected can be bridged.

[0033] In a further embodiment, the contact element comprises a first layer of lamellae with a first opening, an electrical conductor configured as a flexible cable, and a second lamella with a first opening or a second layer of lamellae with a first opening. The first opening of the first lamella can be plugged onto, for example, a terminal configured as a pin of a first battery cell. The first opening of the second lamella can be plugged onto a battery terminal configured as a pin of a second battery cell.

[0034] As a result, battery poles arranged in any direction relative to one another can advantageously be electrically connected by the contact element, in particular larger distances between two pins to be connected can be bridged.

[0035] Of course, these statements also apply to the other openings of the slats.

[0036] The invention is explained in more detail using three exemplary embodiments. The figures show: Fig. 1 a perspective view of a battery block with several battery cells (state of the art), Fig. 2 a plan view of a contact element according to the invention, Fig. 3 a perspective view of layered contact elements, Fig. 4 a plan view of battery cells connected with contact elements, Fig. 5 a plan view of a further embodiment of a contact element and Fig. 6 a plan view of another embodiment of a contact element.

[0037] In the following, the same reference symbols designate elements with the same or similar technical properties.

[0038] Fig. Figure 1 shows a perspective view of a battery block 1. Six battery cells 2 are arranged in a battery cell cage 5 consisting of identical lateral parts 3 and identical frontal parts 4. Each battery cell 2 has a positive pole 6 and a negative pole 7.

[0039] In Fig. 2 shows a plan view of a contact element designed as a lamella 8. The lamella 8 is rectangular and has two long sides 9 and two end faces 10. The lamella 8 also has a first opening 11. Four bendable, spring-elastic tabs 12 protrude into the first opening 11. The tabs 12 cover a first partial area of ​​the first opening 11. Here, it is shown that the first opening 11 is arranged on a first end face 10-1. A further opening 13 is arranged on an end face 10-2 opposite the first end face 10-1. Two tabs 14 protrude into the further opening 13. The tabs 14 are arranged on edges of the further opening 13, which run parallel to the long sides 9 of the lamella 8. In this case, contacts not shown in the first opening 11 and in the further opening 13 of the lamella 8 are designed as pins, e.g. Fig. 1, designed as pins, positive poles 6 and negative poles 7, can be inserted. For example, a positive pole 6-1 of a first battery cell 2 can be electrically connected to a negative pole 7-1 of the battery cell adjacent to the first battery cell 2 by means of the lamella 8. The first opening 11 is plugged onto the positive pole 6-1 designed as a pin, and the further opening 13 is plugged onto the negative pole 7-1 designed as a pin. When plugged in, the flexible tabs 12, 14 stand up and press against an outer surface of the poles 6-1, 7-1 designed as pins. Since only two tabs 14 are arranged in the further opening 13, a relative movement between the positive pole 6-1 and the negative pole 7-1 in the direction of the arrow marked with the reference number 15 is permitted. Tolerances of a relative arrangement of the positive pole 6-1 to the negative pole 7-1 can thus be compensated for in an electrical connection by means of the lamella 8. Furthermore, Fig. 2 schematically shows spacer elements 16 which are arranged on an upper side of the slat 8.

[0040] In Fig. 3 shows a perspective view of slats 8 stacked on top of one another. This shows that the first openings 11 and further openings 13 of the stacked slats 8 are arranged alternately. This means that a first opening 11 of a first slat 8 is arranged above a further opening 13 of the further slat arranged below the first slat 8. At the same time, a first opening 11 of the further slat is arranged below the further opening 13 of the first slat 8. The center lines of the further and first openings of the slats 8 are aligned. The spacer elements 16 make it possible for the tabs 12, 14 to stand up even with layered slats 8 when a pin is inserted into the first or further openings of the slats 8.

[0041] In Fig. 4 shows a plan view of battery cells 2 connected by means of lamellae 8. Here, three battery blocks 1 arranged side by side are shown. The battery blocks 1 each comprise a plurality of battery cells 2, whereby only one battery cell 2 is schematically shown for a left and a right battery block 1. For the middle battery block 1, a series connection of the battery cells 2 is shown by means of the lamellae 8. Here, the positive poles 6 and negative poles 7, which are designed as pins, are each connected by means of the lamellae 8. Here, the negative and positive poles 6, 7, which are designed as pins, are inserted into the further openings 13 and the first openings 11 of the lamellae 8, respectively. Fig. 4 shows that battery cells 2 of adjacent battery blocks 1 can also be electrically and mechanically connected by means of a lamella 8 according to the invention. It is shown that a left battery block 1 is arranged directly adjacent to the middle battery block 1. The lamella 8 connects a positive terminal 6 of a battery cell 2 of the first battery block 1 and a negative terminal 7 of a battery cell 2 of the left battery block 1. Fig. 4 also shows a second contact element 17, which is shown in more detail in Fig. 5. By means of the second contact element 17, battery cells 2 of battery blocks 1 that are not arranged directly adjacent to one another can be electrically connected.

[0042] Fig. 5 shows a plan view of a second contact element 17. The second contact element 17 has a lamella 8. A first opening 11 with four tabs 12 that project into the first opening 11 is arranged in the lamella 8. Furthermore, the second contact element 17 has an electrical interface 19 to an electrical conductor designed as a flexible cable 20. The cable 20 connects the lamella 8 to a further lamella 8, which also has an electrical interface 19 that serves for an electrical connection to the cable 20. The further lamella 8 also has a first opening 11 with tabs 12 projecting into the first opening 11. The first and further lamellas 8 can be plugged onto poles 6, 7 of battery cells 2, which are designed as pins, by means of the first openings 11. The flexible cable 20 can also be used to electrically connect poles 6, 7 that are arranged at a great distance from one another.

[0043] In Fig. 6 shows a plan view of a third contact element 18. The third contact element 18 comprises two lamellae 8. Each of the lamellae 8 has two first openings 11, each with four tabs 12 projecting into the first openings 11. Furthermore, the third contact element 18 comprises two pins 21, which are each inserted into a first opening 11 of a lamella 8. The pins 21 are electrically connected by an electrical conductor designed as a flexible cable 20. By means of the unpopulated, ie free, first openings 11 of the lamellae 8, for example, the Fig.1. For an electrical connection between two poles 6, 7, the free first opening 11 of a first lamella 8 is plugged onto one pole 6, 7. After this, the free first opening 11 of a second lamella 8 is plugged onto another pole 6, 7. The pins 21 can then be plugged into the remaining first openings 11 of the lamellas 8. However, it is also conceivable that the pins 21 are already plugged in when the free first openings 11 are plugged onto the poles 6, 7. List of reference symbols 1 battery block 2 battery cells 3 common part 4 common part 5 Battery cage 6 Positive pole 7 Negative pole 6-1 positive pole 7-1 Negative pole 8 slat, first contact element 9 Long side 10 Front side 10-1 first front side 10-2 second front side 11 first opening 12 tab 13 further opening 14 2 tabs 15 Arrow 16 spacer element 17 second contact element 18 third contact element 19 electrical interface 20 cables 21 cones

Claims

[1] Contact element for electrically contacting at least one battery cell, wherein the contact element (8, 17, 18) comprises at least one lamella (8), wherein the lamella (8) has at least one first opening (11) and at least one bendable tab (12) of the first opening (11), wherein the tab (12) of the first opening (11) projects from an edge of the first opening (11) into the first opening (11) and covers a first partial area of ​​the first opening (11), wherein an electrical contact designed as a pin (6, 7, 21) can be inserted into the first opening (11), wherein a pin (6, 7, 21) inserted into the first opening (11) can be clamped by means of the at least one bendable tab (12), characterized by that the contact element (8, 17, 18) comprises a first and at least one further lamella (8), wherein an underside of the at least one further lamella (8) is arranged above an upper side of the first lamella (8). [2] Contact element according to claim 1, characterized by that the at least first opening (11) is rectangular. [3] Contact element according to claim 2, characterized by that the at least first opening (11) has four tabs (12), wherein in each case one tab (12) projects from one of the four edges of the first opening (11) into the first opening (11). [4] Contact element according to one of the preceding claims, characterized by that the at least one slat (8) forms at least one spacer element (16) on an upper side and / or underside of the slat (8), wherein the at least one spacer element (16) is raised above the upper side and / or underside of the slat (8). [5] Contact element according to one of the preceding claims, characterized byin that the slat (8) has at least one further opening (13) and at least one bendable tab (14) of the further opening (13), wherein the tab (14) of the further opening (13) projects from an edge of the further opening (13) into the further opening (13) and covers a first partial area of ​​the further opening (13), wherein an electrical contact designed as a pin can be inserted into the further opening (13), wherein a pin (6, 7, 21) inserted into the further opening (13) can be clamped by means of the at least one bendable tab (14). [6] Contact element according to claim 5, characterized by that the further opening (13) is rectangular and has two tabs (14), wherein the tabs (14) project from opposite edges of the further opening (13) into the further opening (13). [7] Contact element according to claim 6, characterized bythat the tabs (14) protrude from opposite edges of the further opening (13) into the further opening (13), wherein the edges (13) are arranged parallel to a longitudinal direction of the slat (8). [8] Contact element according to one of the preceding claims, characterized by that a center line of the first opening (11) of the first slat (8) running perpendicular to the top side of the slat (8) is aligned with a center line of the first opening (11) or the further opening (13) of the at least one further slat (8) running perpendicular to the top side of the at least one further slat (8). [9] Contact element according to one of the preceding claims, characterized by that the contact element (17, 18) comprises an electrical conductor designed as a mechanically flexible cable (20).

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