DEVICE FOR BREAKING THE ELECTRICAL CONNECTION TO A BATTERY CELL IN THE EVENT OF OUTGASSING

Abstract

A device for breaking the electrical connection to a battery cell (1) in the event of outgassing has the cell pole (3) on the outgassing valve side connected to an electrical contact point (5) at a connection point (4) via a connecting lead (2) which forms a fuse. The device, requiring few components and having a compact design, enables a reliable electrical and thermal protection of neighboring cells of an outgassing battery cell against overloading and prevents the spread of a thermal runaway. The device provides a spacer (6) between the connection point (4) and the contact point (5) that electrically isolates the connection point (4) from the contact point (5) in the event of outgassing and that retains the cell pole (3).

Claims

1. A device for disconnecting an electrical connection to a battery cell in the event of outgassing, said device comprising: a connecting conductor electrically connecting a connecting point electrically contacting a cell pole on an outgassing valve side of the battery cell to an electrical contact point; said connecting conductor forming a fuse; and a spacer supported between the connection point and the contact point; wherein the spacer retains the cell pole and electrically insulates the connection point from the contact point in the event of outgassing.

2. The device according to claim 1, wherein an outgassing channel is defined between the electrical contact point and the cell pole of the outgassing valve side of the battery cell, and the spacer and the connecting conductor extend through the outgassing space.

3. The device according to claim 1, wherein the connecting conductor extends helically around the spacer.

4. The device according to claim 3, wherein the connecting conductor is a double helix.

5. The device according to claim 1, wherein the spacer is inserted from the contact point into an intermediate space defined by the connecting conductor.

6. The device according to claim 1, wherein the spacer is spaced from the cell pole of the outgassing valve side during operation in which outgassing does not occur.

7. The device according to claim 1, wherein the spacer comprises a flame protection base and a retaining extension projecting from said flame protection base toward the cell pole of the outgassing valve side.

8. The device according to claim 7, wherein the retaining extension comprises an insulation chamber.

9. The device according to claim 1, wherein the contact point forms a cell receptacle for an adjacent battery cell connected in a joining direction, wherein the cell receptacle is inserted with the connecting conductor into a base body and is stop-limited against movement therein beyond a point in the joining direction.

10. The device according to claim 9, wherein the adjacent battery cell has a groove therein, and the base body forms latching arms circumferentially engaging in the groove of the adjacent battery cell.

11. The device according to claim 2 wherein the connecting conductor extends helically around the spacer.

12. The device according to claim 11 wherein the connecting conductor is a double helix.

13. The device according to claim 2, wherein the spacer is inserted from the contact point into an intermediate space defined by the connecting conductor.

14. The device according to claim 3, wherein the spacer is inserted from the contact point into an intermediate space defined by the connecting conductor.

15. The device according to claim 4, wherein the spacer is inserted from the contact point into an intermediate space defined by the connecting conductor.

16. The device according to claim 2, wherein the contact point forms a cell receptacle for an adjacent battery cell connected in a joining direction, wherein the cell receptacle is inserted with the connecting conductor into a base body and is stop-limited against movement therein beyond a point in the joining direction.

17. The device according to claim 16, wherein the adjacent battery cell has a groove therein, and the base body forms latching arms circumferentially engaging in the groove of the adjacent battery cell.

18. The device according to claim 3, wherein the contact point forms a cell receptacle for an adjacent battery cell connected in a joining direction, wherein the cell receptacle is inserted with the connecting conductor into a base body and is stop-limited against movement therein beyond a point in the joining direction.

19. The device according to claim 18, wherein the adjacent battery cell has a groove therein, and the base body forms latching arms circumferentially engaging in the groove of the adjacent battery cell.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In the drawing, the subject matter of the invention is shown by way of example, wherein:

[0017] FIG. 1 shows an exploded view of a device according to the invention, and

[0018] FIG. 2 shows a schematic sectional view of a device according to the invention in the installation position in normal operation.

BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] A device according to the invention for disconnecting the electrical connection to a battery cell 1 in the event of outgassing has a connecting conductor 2 which forms a fuse and connects the outgassing valve-side cell pole 3 of the battery cell 1 at a connection point 4 to an electrical contact point 5 in the form of a contact spring base. A spacer 6, which electrically insulates the connection point 4 from the contact point 5 in the event of outgassing and retains the cell pole 3, is provided between the connection point 4 and the contact point 5. In the event of outgassing, the device according to the invention thus enables, on the one hand, the electrical connection of the defective battery cell 1 to the contact point 5 to be disconnected due to the fusing of the connecting conductor 2 and, on the other hand, the spacer 6 prevents the pole cap 7 on the outgassing valve side from detaching from the battery cell 1, so that the electrode winding cannot escape from the latter but is retained in the defective battery cell 1.

[0020] As can be seen from the embodiment of a device according to the invention shown in FIG. 1 and FIG. 2, the contact point 5 can form a cell receptacle 8 for a battery cell 9 adjoining against a joining direction F, wherein the cell receptacle 8 is inserted with the connecting conductor 2 into a base body 10 and is stop-limited against the joining direction F via stop hooks 11. The base body 10 can also form latching arms 12 for peripheral engagement in a groove 13 of the adjacent battery cell 1. As shown in FIG. 1, contact tongues 14 can project from the contact point 5, which is formed as a contact spring base, against the joining direction F for engaging around the battery cell 9 to be accommodated on the casing side.

[0021] In particular, it can be seen from FIG. 2 that the spacer 6 together with the connecting conductor 2 can pass through an outgassing channel 15 for the hot gas to be discharged, which extends between the electrical contact point 5 and the cell pole 3 on the outgassing valve side. In the shown embodiment of the device according to the invention, the connecting conductor 2 extends as a double helix around the spacer 6, with the conductor tracks of the connecting conductor 2 opening together in the connection point 4. In this case, the spacer 6 is inserted from the contact point 5 into the intermediate space 16 spanned by the connecting conductor 2. The connection point 4 can preferably be connected to the cell pole 3 by a material bond, for example with the aid of a welding process.

[0022] The spacer 6 can have a disk-shaped flame protection base 17, preferably having the diameter of the battery cell, and a retaining extension 18 projecting from this flame protection base 17 in the direction of the cell pole 3 on the outgassing valve side. In this case, the spacer 6 can be inserted into the cell receptacle 8 in a simple manner and, for example, can be stop-limited in the joining direction F by the support edge of the contact point 5. In addition, to further promote the discharge of the hot gas into the outgassing channel 15, the spacer 6 can form guide surfaces 19 extending from the retaining extension 18 to the flame protection base 17. For improved thermal protection, the retention extension 18 may comprise an insulation chamber 20. For example, the spacer 6 may form a cavity that is open to the flame protection base 17. As can be seen, in particular, from FIG. 2, the flame protection base 17 may be provided between the contact point 5 and the cell receptacle 8 of the spacer 6. As can also be seen from FIG. 2, the spacer 6 can be spaced from the cell pole 3 in order, on the one hand, to allow sufficient escape of hot gas and, on the other hand, to prevent the cell pole 3 from escaping and thus a short circuit in the event of outgassing.