Electrochemical accumulator

Abstract

The invention relates to an electrochemical accumulator comprising at least one housing and at least one electrochemical cell disposed in said housing as well as at least two electrical connection terminals for electrically contacting the accumulator, wherein at least one of the connection terminals is formed from at least two interconnected sections of differing metals or metal alloys. The invention furthermore relates to a method for manufacturing an electrochemical accumulator.

Claims

1. An electrochemical accumulator comprising: at least one housing; at least one electrochemical cell disposed in the at least one housing; and at least two electrical connection terminals for electrically contacting the electrochemical accumulator, wherein at least one electrical connection terminal of the at least two electrical connection terminals is formed from at least two interconnected sections of differing metals or metal alloys coupled at an interface, wherein the interface is disposed within a passage defined in a housing wall of the at least one housing, wherein a fastening assembly extends between the passage and the at least one electrical connection terminal, wherein the at least one electrical connection terminal is rotationally symmetric about a central axis of the at least one electrical connection terminal, wherein an upper section of the at least two interconnected sections extends from the interface to an upper surface of the upper section protruding past the fastening assembly, wherein a lower section of the at least two interconnected sections includes a flange that extends from a lower surface of the lower section toward the interface, wherein the lower surface extends substantially parallel to the interface between diametric sides of the flange, and wherein the at least one electrical connection terminal comprises one or more connection features selected from the group consisting of: a first connection feature, wherein the first connection feature includes an additional flange formed within the upper section between the upper surface and the interface, wherein the additional flange extends along the central axis from an intermediate surface of the additional flange toward the interface, wherein the intermediate surface is positioned axially between the upper surface and the interface; a second connection feature, wherein the second connection feature includes the additional flange formed within the upper section between the upper surface of the upper section and the interface, wherein the upper section includes a connection portion extending between the additional flange and the upper surface, and wherein a radial dimension of the connection portion at the additional flange is less than a radial dimension of the upper portion at the interface; or a third connection feature, wherein the third connection feature includes the lower section of the at least two interconnected sections extending from the interface to the lower surface of the lower section, wherein the lower surface is coupled to a positive terminal or a negative terminal of the at least one electrochemical cell, and wherein the fastening assembly comprises: a washer disposed about a circumference of the at least one electrical connection terminal, wherein the washer is positioned between the upper surface of the upper section and the interface; and an insulator disposed about the circumference of the at least one electrical connection terminal, wherein the insulator extends from the lower surface of the lower section and protrudes past the interface, wherein the insulator is disposed about a circumference of the washer and extends along a height of the washer, and wherein the insulator is a single piece component.

2. The electrochemical accumulator according to claim 1, wherein the upper section is indirectly connected to the positive terminal or the negative terminal of the at least one electrochemical cell via the lower section.

3. The electrochemical accumulator according to claim 1, wherein one section of the at least two interconnected sections comprises copper or consists of copper and another section of the at least two interconnected sections comprises aluminum or consists of aluminum.

4. The electrochemical accumulator according to claim 1, wherein the interface extends substantially parallel to the housing wall.

5. The electrochemical accumulator according to claim 1, wherein the at least one electrical connection terminal is sealed relative the housing.

6. The electrochemical accumulator according to claim 1, wherein at least one additional electrical connection terminal of the at least two electrical connection terminals is formed from a housing material of the electrochemical accumulator.

7. The electrochemical accumulator according to claim 6, wherein the at least one additional electrical connection terminal is molded into the housing wall of the electrochemical accumulator such that the at least one additional electrical connection terminal protrudes from an outer contour of the at least one housing.

8. The electrochemical accumulator according to claim 1, wherein the at least one electrochemical cell is a lithium-ion cell.

9. A method for manufacturing an electrochemical accumulator, comprising: providing at least one housing, wherein at least one electrochemical cell is disposed in the at least one housing and at least two electrical connection terminals for electrically contacting the electrochemical accumulator extend from the at least one housing: forming at least one electrical connection terminal of the at least two electrical connection terminals from at least two sections of different metals or metal alloys, wherein the at least two sections of different metals or metal alloys are coupled at an interface; and positioning the at least one electrical connection terminal within a passage defined in a housing wall of the at least one housing, wherein the interface is disposed within the passage, wherein a fastening assembly extends between the passage and the at least one electrical connection terminal, wherein the at least one electrical connection terminal is rotationally symmetric about a central axis of the at least one electrical connection terminal, wherein an upper section of the at least two sections of differing metals or metal alloys extends from the interface and protrudes past the fastening assembly, wherein a lower section of the at least two sections of differing metals or metal alloys includes a flange that extends from a lower surface of the lower section toward the interface, wherein the lower surface extends substantially parallel to the interface between diametric sides of the flange, wherein the fastening assembly comprises a washer disposed about a circumference of the upper section and an insulator disposed about a circumference of the washer, wherein the insulator extends from the lower surface and extends along a height of the washer, and wherein the at least one electrical connection terminal comprises one or more connection features selected from the group consisting of: a first connection feature, wherein the first connection feature includes an additional flange formed within the upper section between an upper surface of the upper section and the interface, wherein the additional flange extends along the central axis from an intermediate surface of the additional flange toward the interface, wherein the intermediate surface is positioned axially between the upper surface and the interface; a second connection feature, wherein the second connection feature includes the additional flange formed within the upper section between the upper surface of the upper section and the interface, wherein the upper section includes a connection portion extending between the additional flange and the upper surface, and wherein a radial dimension of the connection portion at the additional flange is less than a radial dimension of the upper section at the interface; or a third connection feature, wherein the third connection feature includes the lower section of the at least two sections of differing metals or metal alloys, wherein the lower section extends from the interface to the lower surface of the lower section, wherein the lower surface is coupled to a positive terminal or a negative terminal of the at least one electrochemical cell, wherein the washer is positioned between the upper surface of the upper section and the interface, and wherein the insulator is a single piece component that extends from the lower surface of the lower section and protrudes past the interface.

10. The method according to claim 9, comprising coupling the at least two sections of differing metals or metal alloys at the interface via a friction welding process.

11. The method according to claim 10, comprising coupling the lower surface of the lower section to the positive terminal or the negative terminal of the at least one electrochemical cell, wherein the lower surface extends substantially parallel to the housing wall.

12. The electrochemical accumulator according to claim 1, wherein, when the additional flange is formed within the upper section, the washer is disposed axially between the additional flange and a receiving surface of the insulator with respect to the central axis of the at least one electrical connection terminal.

13. The electrochemical accumulator according to claim 12, wherein a radial dimension of the additional flange extends substantially parallel to the interface.

Description

(1) The following will reference the drawings in describing the invention in greater detail by way of embodiments.

(2) Shown are:

(3) FIG. 1 an isometric view of an electrochemical accumulator;

(4) FIG. 2 a sectional representation of part of the electrochemical accumulator of FIG. 1; and

(5) FIG. 3 an isometric view of a further embodiment of an electrochemical accumulator.

(6) The figures make use of the same reference numerals for equivalent elements.

(7) FIG. 1 shows an electrochemical accumulator 1 having a prismatic; i.e. substantially rectangular housing 2. Two electrical connection terminals 4, 5 protrude from the housing 2 of the accumulator 1 at one housing wall 3 of said housing 2. The connection terminals 4, 5 are electrically connected to one or more electrochemical cells disposed within the housing. Connection terminal 4 can have for example the cylindrical form recognizable in FIG. 1. The other connection terminal 5 exhibits a more complex form which will be described below in greater detail referencing the sectional representation provided in FIG. 2.

(8) The connection terminal 5 is configured as a connection terminal having at least two interconnected sections of differing metals or metal alloys. This is depicted in FIG. 2 by means of an upper section 11 of the connection terminal along with a lower section 10 of the connection terminal arranged underneath. A junction 12 can be seen between the sections 10, 11 extending substantially parallel to the housing wall 3 or to the respective external surface of the housing wall 3 respectively. The upper section 11 is composed e.g. of aluminum, the lower section 10 of copper. The lower section 10 is connected to an electrical terminal 7 of a lithium-ion cell 6 disposed in the housing 2 by means of metal strips 8, 9, e.g. copper strips.

(9) Components 8, 9, 10 are in particular formed from the same metal material. They can be connected together by welding, for example. The upper section 11 of the connection terminal Scan be welded to the lower section 10 by spin welding.

(10) The housing 2 can in particular consist of a metallic, i.e. electrically conductive material. For this reason, the seal 13 is made from an electrically insulating material, particularly a plastic material. Connection terminal 5 is inserted through the seal 13 into the housing opening of the housing wall 3 and additionally sealed against the housing. The seal 13 in particular prevents external environmental influences from having any effect on components within the interior of the housing 2 or on the junction between the sections 10, 11 of the connection terminal 5. The upper section 11 of connection terminal 5 can additionally be secured in the seal 13 by a washer 14 to protect and mechanically support the seal 13.

(11) FIG. 3 shows a further embodiment of an electrochemical accumulator which differs from the embodiment of FIG. 1 by a different embodiment to the connection terminal 4. It can be seen that the connection terminal 4 has a rectangular contour when viewed from above. The connection terminal 4 can be made from the material of housing 2, e.g. aluminum, and directly formed on the housing wall 3 in a molding process. Doing so does away with the manufacturing and mounting of a second connection terminal 4 as a separate component.