EP1831962A2

EP1831962A2 - Battery connector and method for the production thereof

Info

Publication number: EP1831962A2
Application number: EP05826374A
Authority: EP
Inventors: Jens Trimborn
Original assignee: Froetek Kunststofftechnik GmbH
Current assignee: Froetek Kunststofftechnik GmbH
Priority date: 2004-12-21
Filing date: 2005-12-21
Publication date: 2007-09-12
Also published as: DE102004062676A1; WO2006067166A3; WO2006067166A2

Abstract

The invention relates to a battery connector (100) for accumulator batteries in which the connecting plate (23) of the contact piece (20) is matched to the cross-section of the cable (10) to be connected so that the ratio of width (d) to height (h) of the flatly pressed bundle of the individual wires (11) of the cable (10) is between 2:1 and 10:1. In addition, the invention relates to other designs of battery connectors and to the production thereof, particularly by connecting the individual wires to a contact piece under pressure, while heating, and while adding a molten metallic additive substance.

Description

FRÖTEK Kunststofftechnik GmbH An der Unteren Söse 24-30 37520 Osterode

Battery connector and method for its manufacture

The invention relates to battery connectors for accumulator batteries and contact pieces thereof and to devices and methods for producing such battery connectors.

From WO 00/08718 a battery connector is known, in which at the ends of an insulated copper wire cable in each case the connection plate of a contact piece made of copper or brass is attached. The contact plates of the contact pieces have holes through which a pole screw can be plugged and screwed into the battery terminal of a storage battery to electrically couple the cells of the battery to the battery connector. Also the contact plates are insulated like the copper wire cable. By welding, a good connection between the wires of the battery connection cable and the contact piece is achieved, which is suitable for the electrical conduction of the withdrawn, typically high currents. The contact pieces of said battery connector are punched from a band-shaped flat material and have a substantially rectangular shape in plan view.

Against this background, it was an object of the present invention to provide improved battery connectors, in particular, the reliability of the connection between the cable and contact piece to be increased and the application of the battery connector to be extended.

This object is achieved by preferably fully insulated battery connectors with the features of claim 1 or 7, by a contact piece with the features of claim 6, by a device having the features of claim 9 and solved by methods having the features of claims 8 and 10. Advantageous embodiments are contained in the subclaims.

A. Contact pieces with dimensions adapted to the cable cross-section

According to a first aspect, the invention relates to a preferably fully insulated battery connector for storage batteries, which includes a contact piece with a contact plate and a connection plate and a cable. The contact plate is used in the usual way to make the electrical contact to the pole of a rechargeable battery or the like, including the contact plate usually has a through hole for inserting a pole screw, with which the contact piece can be screwed to the lead terminal of a battery. The cable of the battery connector further includes a plurality of individual wires which, as a bundle of substantially rectangular cross-section, fills the width of the terminal region after joining and is connected to the terminal plate (e.g.

B. by welding, soldering or crimping) are connected.

According to a first variant, the battery connector described above is characterized in that the width of the terminal plate to the cable after joining is different (preferably smaller) than the width of the contact plate (i.e., in the terminal region to the battery post). According to a second variant, the battery connector is characterized in that the ratio of the width of the connection plate to the cable to the height of the extended bundle of individual wires is approximately 2: 1 to 10: 1. Of course, both variants can also be realized simultaneously in a battery connector.

In a particularly advantageous embodiment, the width of the connection plate in the joining area to the cable is approximately 12.5 to 15.5 mm (ie 14 mm ± 10%) and the cross-sectional area of the associated cable is approximately 25-35 mm ² . In another preferred dimension, the width of the terminal plate is 17 mm ± 10% with a cross-sectional area of the cable of 50-95 mm ² . In the preferably fully insulated battery connector according to the first aspect of the invention, the width of the connection plate of the contact piece is matched to the cable to be connected or its cross section. This ensures that the spread out to a rectangular bundle cable in the connection area on the terminal plate assumes a certain dimension or certain proportions, on the one hand have a favorable effect on the mechanical connectivity to the terminal plate and on the other hand cause a good power transfer. Furthermore, the emergence of loose individual wires is avoided, which is often observed in conventional methods in parts of the wire bundle.

B. Row connector

According to a second aspect of the present invention, this relates to a contact piece for a battery connector, which has at least one connection in the cable center, wherein the contact piece has a contact plate and at least two connection plates for fixing the ends of two cables. Furthermore, the invention relates to a battery connector which contains such a contact piece.

Battery connectors with at least one medial connection point are known per se as "row connectors". They are usually made by sliding a copper sleeve over the cable of the battery connector and flattening it at a stripped point of the cable. Since the sleeve has to fit over the insulation of the cable, it has an oversize, which has an adverse effect on the resulting from the flattened sleeve contact piece with respect to the pressing ratio. Such disadvantages are avoided in the battery connector described above, since there is a contact piece with two connection plates is used, to which the ends of two individual cables are attached. The middle contact piece therefore has the same solid mechanical and electrical connection to the cable as the contacts at the ends of the battery connector. Unlike conventional row connectors no loosening of the individual wires by changing heating operations on.

C. Simultaneous application of contact pieces

According to a third aspect, the invention relates to a method for producing a battery connector, wherein at two or more locations of a cable, contact pieces are fixed in a thermal process (in particular welding or soldering). Corresponding thereto, the invention comprises a device for producing a battery connector which comprises at least two thermal connection stations (in particular welding and / or soldering stations) which can be operated in parallel to simultaneously connect at least two contact pieces to the ends (at least) of a cable.

In battery connectors, each with a contact piece at the two ends of a cable, the two contact pieces are usually connected sequentially to the cable by welding or soldering. In this case, a single welding or soldering station is used, in which the cable ends are inserted one after the other. However, it has been found that the connections thus obtained between the cable ends and the contact pieces can not be optimal or at least of different quality. One reason for this seems to be that the cable is already preheated when attaching the second contact piece and the second connection process thereby takes place differently. This is particularly noticeable in short battery connectors. The above-proposed method or apparatus avoids such problems because the plurality of contact pieces are simultaneously connected to the cable (eg, to its ends or optionally to the central area of the cable as well). All connection processes run in the same way, so that the connections are all of the same quality, which can be uniformly optimized. D. Diffusion welding or joining with additive

According to a fourth aspect, the invention relates to a method for producing an electrically conductive, permanent connection between a cable having a plurality of individual wires and a metallic connecting piece, in particular for connecting the contact pieces of a battery connector with the associated cable. The procedure is characterized by the following steps:

a) pressing a bundle of individual wires to the connector. Under certain circumstances, high forces of, for example, 4200 to 6500 Newton can be exerted here.

b) heating the pressed bundle of individual wires, without resulting in total melting of the individual wires and / or the connecting piece. A local melting, in particular of the individual wires at their points of contact, is permissible on the other hand. The heating can be carried out in particular by passing an electrical current in the transverse direction through the individual wires and the connecting piece.

c) adding a metallic additive, which melts during the preceding step b) and penetrates into the voids between the individual wires of the bundle. As a metallic additive, various metals or alloys may come into question, which melt at the temperatures involved. In particular, the metallic additive may be a silver alloy, the silver content of which is preferably at least 40% by weight.

With the method described compounds of high mechanical strength and good electrical conductivity can be achieved. In contrast to (soft) soldering processes, in the described method preferably no flux is used which would etch the surfaces of the metals involved. It is therefore not a soldering in the usual sense. Furthermore, the connection is not made by conventional welding or crimping with subsequent addition of metallic filler material, in which the metals involved in the connection area are completely converted to the melting state. However, the combination of pressure and heating can locally lead to melting and / or diffusion processes on the contacting surfaces.

E. Further embodiments: cranking, recess etc.

The features of the contacts or battery connectors, which are designed according to the above-described various aspects of the invention, can be combined with each other and / or supplemented by further optional features. Thus, for example, in the contact pieces, the contact plate, which establishes the electrical contact with the battery, and the connection plate, to which the cable is attached, be arranged offset in height relative to one another. By such a "cranking" of the contact piece can be achieved that the connection plate comes to lie approximately at the height of the central axis of the cable, so that the battery connector receives a total of a symmetrical shape.

According to another embodiment of the contact pieces or battery connector, the contact piece on its underside, which by definition is in the use state of the battery facing, at least one recess into which engages a top of the contact piece covering Isolierumspritzung. Even if the entire other bottom of the contact piece remains free of the Isolierumspritzung, pushing out of the contact piece is prevented from the encapsulation by their intervention in the recesses.

In other developments, the contact piece including its encapsulation and an associated pole screw may be rounded, reference being made in this respect to DE 103 27 349.2, in which further embodiment variants are described and which is therefore fully incorporated into the present application. Furthermore, the contact piece can be provided with a coating of a soft material (cf. DE 103 02 270.8, which is also incorporated in full in the present application).

In the following, the invention will be explained by way of example with the aid of the figures. It shows:

Figure 1 is a plan view and a cross section of the connection region of a cable to a contact piece;

Figure 2 is a side view of a battery connector (partially in section) with cranked contacts;

Figure 3 is a section through and a plan view of a battery connector with a center port;

Figure 4 shows a longitudinal section and a cross section through a single wire bundle on a connection plate during diffusion welding with the addition of a filler material.

The battery connectors shown in the figures are used in particular for connecting the poles of accumulator batteries, in which respect reference is made to WO 00/08718 and DE 103 27 349 for more detailed description. In principle, however, other applications of the illustrated constructions and methods are possible.

1 shows a plan view (left) and a cross section (right) along the dashed line AA of the plan view through the end region of a battery connector 100, with a metallic contact piece 20 (eg of copper or brass) and a cable 10 too recognize. The cable 10 includes a plurality of individual wires 11 (e.g., copper) which are stripped of the outer cable insulation at the end of the cable and laid out into a flat bundle of substantially rectangular cross-section. The bundle extends with a height h over the entire width d of the connection plate 23 of the Contact piece 20, wherein the product of width and height gives the cross-section Q of the cable: Q = h d.

In conventional battery connectors, the contact piece is designed as a rectangular plate of uniform width D, this width being predetermined by the contact plate 21 and in particular the through hole 22 to be accommodated therein. In contrast, in the contact piece 20 shown in FIG. 1, the widths D of the contact plate 21 and d of the terminal plate 23 are independent of each other and (as a rule) different. Thus, the width D of the contact plate 21 can be optimally selected as usual with regard to the battery terminal to be connected and the pole screw or the through-hole 22. The width d of the terminal plate 23, however, depends on the cross-section Q of the cable 10 to be connected in such a way that on the one hand, the bundle of individual wires 11 over the entire width d of the terminal plate 23 can be pressed flat while the other one with respect to the mechanical and electrical connection has optimal height h or reserves. It turns out that the ratio of width d to height h is preferably in a range of d: h = 2: 1 to 10: 1. In particular, it is preferred if, on a connection plate with the width d = 14 mm, a cable 10 with the cross section Q = 25 to 35 mm ² and on a connection plate with the width d = 17 mm, a cable 10 with the cross section Q = 50 to 70 mm ^{2 is} connected. The connection between the bundle of individual wires 11 and the connection plate 23 can be effected by welding, soldering or other (see below) techniques.

Furthermore, in Figure 1 in the contact plate 21 of the contact piece 20, a nose or recess 24 on the outer edge recognizable, in which a plastic encapsulation (not shown) can engage, which surrounds the contact piece and the cable connection protective in the finished battery connector. By this engagement prevents the contact piece 20 can be pushed down from the extrusion coating.

Figure 2 shows a battery connector 200 in a side view (90 ° rotated relative to the left part of Figure 1), wherein the mutually rotated by 180 ° mounted contact pieces 20 and the associated insulation injection 30 are shown in section along its center line. Evident here is a cranking or step between the contact plate 21 and the connection plate 23 of the contact piece 20. The step, which can be easily produced without machining by bending, the contact plate 21 comes to lie approximately at the height of the cable 10 , The entire battery connector 200 can be formed in this way with matching heights of the contact pieces 20 in relation to the top and bottom.

FIG. 3 shows a battery connector 300 with a central connection piece. This so-called "row connector" consists of (at least) two cable sections 10a, 10b, which are connected at their outer ends on the one hand with terminal contact pieces 20 and on the other hand with a central contact piece 120. The middle contact piece 120 has a contact plate 121 with a through hole for a pole screw and two connection plates 123a, 123b, which attach at the opposite ends of the contact plate 121 in the example shown. Alternatively, however, more than two such connection plates could be provided and / or attach the connection plates at different angles to the contact plate 121. The cable ends can each be connected in a known manner to the connection plates 123a, 123b (eg welding, soldering).

In the battery connectors 200, 300 shown in FIGS. 2 and 3, the plurality of contact pieces 20, 120 are preferably connected to the cables 10, 10a, 10b simultaneously, e.g. B. verscheißt or soldered. Thus, for example, a device may be provided in which the left and right contact piece 20 are stored according to Figure 2 in parallel in two opposing stations, and wherein the laid-cable 10 is simultaneously connected to the contact pieces. The attachment of the contacts is carried out in this way completely symmetrical, ie, over a successive attachment of the contacts no asymmetries arise by preheating a page. In FIG. 4, in a longitudinal section (left) and a cross section along the line AA (right) through the connection region between a bundle of individual wires 11 and a connecting piece 23, a preferred method for producing a mechanically and electrically good connection is shown. The metallic connection piece 23 rests on a support 42 (lower electrode) and is clamped on both sides by jaws 41, 43 (ceramic slide). The jaws 41, 43 at the same time enclose the bundle of the individual wires 11 between them, this bundle being compressed from above by a pressing jaw 44 (upper electrode). In a manner known from resistance welding, an electric current can be conducted from the pressing jaw 44 to the carrier 42 through the individual wires 11 and the connecting piece 23, which leads to heating. However, unlike resistance welding, this heating should not be so great that the individual wires 11 or the connecting piece 23 melt more or less completely. Rather, only the melting point of an additive 50, z. Example, a silver alloy with at least 40 wt .-% silver can be achieved, so that the additive 50 penetrates in liquid form into the cavities between the individual wires 11. In the example shown, the additive is located as a band 50 between the connector 23 and the bundle of individual wires 11. A flux as soldering is not applied. Due to the heating, the pressure and the current flow, a diffusion of atoms can occur in the contact points between the individual wires 11 ("diffusion welding"). It turns out that the explanatory connection technique, which is neither pure welding nor pure soldering, leads to extremely good mechanical and electrical connections.

Claims

claims

1. Battery connector (100, 200, 300) for storage batteries, comprising a contact piece (20, 120) with a contact plate (21, 121) and a connection plate (23, 123 a, 123 b) and a cable (10, 10 a, 10 b) a plurality of individual wires (11), which are laid out as bundles of substantially rectangular cross-section over the entire connection plate and connected thereto, characterized in that the width (d) of the connection plate (23) is different from the width (D) of the contact plate (20) is.

Second battery connector (100, 200, 300) for storage batteries, in particular according to claim 1, comprising a contact piece (20, 120) with a contact plate (21, 121) and a connection plate (23, 123 a, 123 b) and a cable (10, 10a, 10b) having a plurality of individual wires (11) which are laid out as bundles of substantially rectangular cross-section over the entire terminal plate and connected thereto, characterized in that the ratio of width (d) of the terminal plate (23) to the height (h) of the spread bundle of the individual wires (11) is about 2: 1 to 10: 1.

3. Battery connector according to claim 1 or 2, characterized in that the width (d) of the terminal plate 14 mm ± 10% at a cross-sectional area of the cable (10) of 25-35 mm ² , or 17 mm ± 10% at a cross-sectional area of the Cable (10) of 50-70 mm ² .

4. Battery connector according to at least one of claims 1 to 3, characterized in that it comprises an insulation injection, which surrounds the contact piece and the cable connection protective.

5. Battery connector according to at least one of claims 1 to 4, characterized in that the cable (10) with the connection plate (23) is joined together by welding, soldering or crimping.

6. contact piece (120) for a battery connector (300) having at least one central terminal, characterized in that it comprises a contact plate (121) and two connection plates (123a, 123b) for fixing the ends of two cables (10a, 10b).

7. battery connector (300), characterized by a contact piece (120) according to claim 6.

8. A method for producing a battery connector (100, 200, 300), characterized in that at several points of a cable (10, 10 a, 10 b) contact pieces (20, 120) attached at the same time with a thermal process, in particular welded or soldered become.

9. A device for producing a battery connector (100, 200, 300), comprising at least two thermal connection stations, in particular welding stations and / or soldering stations, which can be operated in parallel to two contact pieces (20, 120) simultaneously with the ends of a cable (10 , 10a, 10b).

10. A method for producing an electrically conductive, permanent connection between a cable (10, 10a, 10b) with a plurality of individual wires (11) and a metallic connecting piece (23, 123a, 123b), characterized by the following steps: a) pressing a Bundle of the individual wires (11) to the connecting piece (23, 123 a, 123 b); b) heating the bundle of individual wires, without there being an overall melting of the individual wires and / or the connecting piece; c) adding a metallic additive (50), which melts during step b) and penetrates into the voids between the individual wires (11) of the bundle.

11. The method according to claim 10, characterized in that the

Additive (50) is a silver alloy, preferably having a silver content of at least 40%.

12, contact piece (20, 120) or battery connector (100, 200, 300), designed or manufactured according to at least one of claims 1 to 11, characterized in that the connection plate (23, 123 a, 123 b) and the contact plate (21, 121 ) are offset in height.

13. contact piece (20, 120) or battery connector (100, 200, 300), designed or manufactured according to at least one of claims 1 to 12, characterized in that the contact piece on its underside at least one recess (24), in which a the top of the contact piece covering Isolierumspritzung (30) engages.