Method for producing an electrically conductive bond between an electrical line and an electrically conductive component and assembly produced using the method

Abstract

To provide a method for producing an electrically conductive bond between an electrical line, which includes a plurality of individual conductors, and an electrically conductive component, including producing from a crimp element blank a crimp element enclosing portions of the individual conductors, the crimp element including a continuous side and a discontinuous side, at which edge regions of the crimp element lie opposite one another, and substance-to-substance bonding of the crimp element with a contact surface of the component, which is simple to carry out and nevertheless always results in a robust substance-to-substance bond between the crimp element and the component, it is proposed that the crimp element be produced in such a way that the continuous side of the crimp element includes two bearing surfaces which are spaced from one another, at which the crimp element is substance-to-substance bondable to the contact surface of the component.

Claims

1. A method for producing an electrically conductive bond between an electrical line, which comprises a plurality of individual conductors, and an electrically conductive component, comprising the following: producing from a crimp element blank a crimp element enclosing portions of the individual conductors, the crimp element comprising a continuous side and a discontinuous side, at which edge regions of the crimp element lie opposite one another; and substance-to-substance bonding of the crimp element at the continuous side thereof with a planar contact surface of the component; wherein the crimp element is produced in such a way that the discontinuous side of the crimp element comprises two bearing surfaces which are formed by crests of the edge regions of the crimp element and are spaced from one another in a transverse direction of the crimp element by an intermediate recess formed on the discontinuous side of the crimp element, wherein the crimp element is substance-to-substance bondable to the contact surface of the component at said bearing surfaces on the discontinuous side of the crimp element, and that the continuous side of the crimp element comprises two bearing surfaces which are spaced from one another in the transverse direction of the crimp element, wherein the crimp element is substance-to-substance bondable to the contact surface of the component at said bearing surfaces on the continuous side of the crimp element, wherein a recess is produced on the continuous side of the crimp element before the crimp element comes into contact with the contact surface of the component, wherein the recess extends from a front edge of the crimp element to a rear edge of the crimp element, wherein the crimp element is substance-to-substance bonded to the contact surface of the component by an ultrasonic welding process at the bearing surfaces on the continuous side of the crimp element between the front edge and the rear edge of the crimp element, and wherein said bearing surfaces on the continuous side of the crimp element are arranged on an outer surface of the crimp element, facing away from the individual conductors of the electrical line.

2. The method according to claim 1, wherein the recess is produced by impressing.

3. The method according to claim 1, wherein the crimp element has a cross-section which resembles the number 8.

4. The method according to claim 1, wherein the crimp element blank contains a metallic material.

5. The method according to claim 1, wherein substance-to-substance bonding of the crimp element with the component proceeds by a welding process.

6. The method according to claim 1, wherein the component is formed as a cell connector for electrically conductively bonding cell terminals of electrochemical cells of an electrochemical device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic perspective representation of an end region of an electrical line, which comprises a plurality of individual conductors, which have been enclosed by a crimp element in the form of a B-crimp;

(2) FIGS. 2 and 3 are schematic perspective representations which illustrate the production of a crimp element from a crimp element blank at end portions of the individual conductors of the electrical line;

(3) FIG. 4 shows a schematic section through an assembly comprising an electrical line with a plurality of individual conductors, a crimp element in the form of a B-crimp enclosing end portions of the individual conductors and a component welded to a continuous side of the crimp element;

(4) FIG. 5 shows a schematic section through an alternative embodiment of the assembly of FIG. 4, in which the component is welded to a discontinuous side of the crimp element;

(5) FIG. 6 is a schematic perspective representation of an end portion of an electrical line, which comprises a plurality of individual conductors, and a crimp element enclosing portions of the individual conductors, the continuous side of which crimp element comprises two bearing surfaces which are spaced from one another, at which the crimp element is substance-to-substance bondable to a contact surface of a component;

(6) FIG. 7 shows a schematic section through an assembly, which comprises the electrical line and the crimp element of FIG. 6 and a component welded to the crimp element on the discontinuous side thereof; and

(7) FIG. 8 shows a schematic section through an alternative embodiment of the assembly of FIG. 7, in which the component is welded to the crimp element on the continuous side thereof.

(8) Identical or functionally equivalent elements are provided with the same reference signs in all the figures.

DETAILED DESCRIPTION OF THE INVENTION

(9) An assembly according to the prior art illustrated in FIGS. 1 to 5 and designated overall as 100 comprises an electrical line 102 in the form of a cable 104 which comprises a plurality of stranded wires or individual conductors 106 and an electrically insulating covering 108, a crimp element 110 in the form of a B-crimp 112, which encloses end portions of the individual conductors 106, and a component 114 of an electrically conductive material (see in particular FIGS. 1, 4 and 5).

(10) The crimp element 110 has been produced from a crimp element blank 116 illustrated in FIG. 2 in that, using a crimping tool (not shown), mutually opposing edge regions 118a, 118b are bent around the end portions 120, not provided with the covering 108, of the individual conductors 106 and pressed against the individual conductors 106 in such a way as to result in the crimp element 110 with the substantially B-shaped cross-section illustrated in FIGS. 1, 4 and 5.

(11) During production of the crimp element 110, the end portions 120, enclosed by the crimp element 110, of the individual conductors 106 are compacted and pressed together in force-locking manner.

(12) The resultant crimp element 110 comprises a continuous side 122 with an unbroken, substantially planar bearing surface 124 and a side opposite the continuous side 122, hereinafter designated discontinuous side 126, at which the curved edge regions 118a and 118b of the crimp element 110 lie opposite one another.

(13) Provision is preferably made for the edge regions 118a and 118b to end at a short spacing from one another or to touch one another.

(14) The crests of the edge regions 118a and 118b remote from the continuous side 122 of the crimp element 110 form two bearing surfaces 128a and 128b respectively of the discontinuous side 126 of the crimp element 110, which are spaced from one another in a transverse direction 130 of the crimp element 110 by an intermediate recess 132.

(15) The base of the recess 132 is formed for example by the free edges 134a and 134b of the edge regions 118a or 118b respectively of the crimp element 110.

(16) The transverse direction 130 of the crimp element 110 is oriented perpendicular to a longitudinal direction 136 of the crimp element 110, which direction extends substantially parallel to the longitudinal direction of the electrical line and substantially parallel to the free edges 134a and 134b of the crimp element 110.

(17) The lateral free edges 134 of the crimp element 110 join a front edge 138 to a rear edge 140 of the crimp element 110.

(18) For substance-to-substance bonding of the crimp element 110 to the component 114, the crimp element 110 may be applied in two different orientations to a contact surface 142 of the component 114, namely with the continuous side 122 facing the component 114, as shown in FIG. 4, or with the discontinuous side 126 facing the component 114, as shown in FIG. 5. In the case of the orientation illustrated in FIG. 4, the crimp element 110 is welded, for example by an ultrasonic welding process, along the entire planar bearing surface 124 of the continuous side 122, forming a weld zone 144.

(19) In the case of the alternative orientation shown in FIG. 5, the crimp element 110 is welded, for example by an ultrasonic welding process, at the bearing surfaces 128a and 128b which are spaced from one another, forming two weld zones 146a and 146b which are spaced from one another in the transverse direction 130.

(20) In the two alternative embodiments of the substance-to-substance bond according to FIGS. 4 and 5, the peel forces, i.e., the shear forces, needed to detach the crimp element 110 from the component 114 are very different, specifically the peel forces in the variant embodiment illustrated in FIG. 5, in which the crimp element 110 faces the component 114 with its discontinuous side 126, are markedly higher than in the variant embodiment illustrated in FIG. 4, in which the crimp element 110 rests with its continuous side 122 against the component 114.

(21) The reason for this in particular resides in the greater localization of the energy input into the weld zones 146a, 146b between the crimp element 110 and the component 114 during substance-to-substance bonding and in the greater localization of the shear forces acting on the weld zones 146a, 146b in the orientation of the crimp element 110 relative to the component 114 shown in FIG. 5.

(22) Since higher peel forces mean a more robust and durable bond between the crimp element 110 and the component 114, the crimp element 110 must therefore be applied to the component 114 in the orientation illustrated in FIG. 5 in order to achieve higher peel forces and thus a more robust substance-to-substance bond between the crimp element 110 and the component 114.

(23) In the assembly 100 formed according to the invention and illustrated in FIGS. 6 to 8 of an electrical line 102 with individual conductors 106, a crimp element 110 and a component 114, the peel forces are on the contrary always substantially of equal magnitude, irrespective of whether the crimp element 110 is applied with its discontinuous side 126 against the component 114, as illustrated in FIG. 7, or with its continuous side 122, as illustrated in FIG. 8.

(24) This is achieved in that the crimp element 110 is produced in such a way that the continuous side 122 of the crimp element 110 also comprises two bearing surfaces 148a and 148b which are spaced from one another, at which the crimp element 110 is substance-to-substance bondable with the contact surface 142 of component 114, wherein the bearing surfaces 148a and 148b are separated from one another in the transverse direction 130 of the crimp element 110 by a recess 150 arranged therebetween.

(25) The recess 150 preferably extends from the front edge 138 of the crimp element 110 as far as to the rear edge 140 thereof.

(26) The recess 150 is preferably produced during the crimping process, i.e., during production of the crimp element 110 from the crimp element blank 116, for example by impressing.

(27) Impressing may proceed for example using a die provided in a crimping tool, which die is preferably substantially complementary in form to the recess 150.

(28) The crimp element 110 preferably has substantially the same radius of curvature in the region of the bearing surfaces 148a and 148b of the continuous side 122 of the crimp element 110 as at the bearing surfaces 128a and 128b respectively of the discontinuous side 126 of the crimp element 110.

(29) It is particularly favorable for the crimp element 110 to be substantially mirror-symmetrical with regard to the bearing surfaces 148a, 148b of the continuous side 122 of the crimp element 110 and the bearing surfaces 128a, 128b of the discontinuous side 126 of the crimp element 110 relative to a longitudinal central plane 152 of the crimp element 110 oriented parallel with the transverse direction 130 and parallel with the longitudinal direction 136 of the crimp element 110 and/or substantially rotationally symmetrical with regard to rotation of the crimp element 110 by 180 about a longitudinal center axis 154 of the crimp element 110 extending parallel to the longitudinal direction 136.

(30) In this way it is ensured that the crimp element 110 is substance-to-substance bonded to the component 114, for example by an ultrasonic welding process, at two weld zones 156a and 156b spaced from one another in the transverse direction 130 of the crimp element 110 even if said crimp element is applied with its continuous side 122 against the component 114.

(31) The weld zones 156a and 156b which bring about the substance-to-substance bond between the crimp element 110 and the component 114 when the crimp element 110 is applied with its continuous side 122 against the component 114 thus have substantially the same geometry as the weld zones 146a and 146b which bring about the substance-to-substance bond between the crimp element 110 and the component 114 when the crimp element 110 is applied with its discontinuous side 126 against the component 114, as illustrated in FIG. 7.

(32) When using the crimp element 110 according to the invention, the peel forces are thus of substantially equal magnitude irrespective of the position of the crimp element 110 relative to the component 114 such that, when bonding the crimp element 110 to the component 114, it is not necessary to note whether the crimp element 110 is applied with the discontinuous side 126 or with the continuous side 122 against the component 114.

(33) Assembly work is thereby significantly simplified.

(34) In contrast with the substantially B-shaped crimp element 110 according to the prior art, as illustrated in FIGS. 1 to 5, the crimp element 110 according to the invention illustrated in FIGS. 6 to 8 has a cross-section which resembles the number 8.

(35) Apart from the additional impressing of the recess 150 on the continuous side 122 of the crimp element 110, production of the crimp element 110 corresponds to the production process according to the prior art as explained above with reference to FIGS. 1 to 5.

(36) A material which may be considered for the crimp element blank 116 is in principle any electrically conductive, workable material.

(37) Preferably, the crimp element blank 116 is formed from a metallic material, for example from copper or a copper alloy.

(38) The individual conductors 106 of the electrical line 102 may in principle also be formed from any material that has sufficient electrical conductivity.

(39) The individual conductors 106 may in particular be formed from copper or a copper alloy.

(40) Component 114 may in principle be formed from any material that has sufficient electrical conductivity.

(41) Component 114 is preferably a constituent of a cell contacting system, with which cell terminals of electrochemical cells of an electrochemical device are bonded together.

(42) Provision may in particular be made for component 114 to be a cell connector 156 which serves to electrically conductively bond cell terminals of various electrochemical cells of an electrochemical device.

(43) Such a cell connector 156 is preferably formed from an electrically conductive metallic material, for example from copper or a copper alloy or from aluminum or an aluminum alloy.

(44) The electrically conductive bond between the electrical line 102 and such a cell connector 156 may in particular serve to transfer the electrical potential prevailing at the connection point of the cell connector 156 via the electrical line 102 to a monitoring device of the electrochemical device.

(45) An assembly 100 according to the invention of the above-described type may furthermore be used to produce an electrically conductive bond between a temperature sensor and a monitoring device of the electrochemical device.