Current Collector for an Electrochemical Energy Storage Apparatus

Abstract

An electrochemical energy storage apparatus, in particular a rechargeable lithium-ion battery, having at least one current collector device with at least one current conductor arm, and at least one energy storage cell which has at least one anode, one cathode and one separator. The separator touches the anode and the cathode at least in sections in, in each case, a separator contact area. The current conductor arm can be electrically conductively connected to, in each case, at least one anode or cathode by way of a current output conductor contact area. A surface normal on the current output conductor contact area and a surface normal on the separator contact area form an acute angle α. This angle α is selected from a range which is greater than 5°, with preference greater than 15°, preferably greater than 25° and particularly preferably greater than 35°, and furthermore the angle α is less than or equal to 90°, with preference less than 75°, preferably less than 65° and particularly preferably less than 45°.

Claims

1. An electrochemical energy storage apparatus, comprising: at least one current collector device with at least one current conductor arm; at least one energy storage cell which has at least one anode, one cathode and one separator, wherein the separator touches the anode and the cathode at least in sections in, in each case, a separator contact area, the current conductor arm is electrically conductively connectable to, in each case, at least one anode or cathode via a current output conductor contact area, a surface normal on the current output conductor contact area and a surface normal on the separator contact area enclose an acute angle α, and the angle α is selected from a range which is greater than one of: 5°, 15°, 25° or 35°, and is less than or equal to one of: 90°, 75°, 65° or 45°.

2. The electrochemical energy storage apparatus according to claim 1, wherein the apparatus is a rechargeable lithium-ion battery.

3. The electrochemical energy storage apparatus according to claim 1, wherein the current collector device has a second current conductor arm, a surface normal on a second current output contact area and the surface normal on the separator contact area encloses an acute angle β, the angle β is selected from a range which is greater than one of: 5°, 15°, 25° or 35°, and is less than or equal to one of 90°, 75°, 65° or 45°.

4. The electrochemical energy storage apparatus according to claim 2, wherein the first and the second current conductor arm are inclined diametrically opposed to each other.

5. The electrochemical energy storage apparatus according to claim 2, wherein the current conductor arms are arranged mirror symmetrically with respect to each other at least in sections or completely.

6. The electrochemical energy storage apparatus according to claim 1, further comprising: at least one second energy storage cell, wherein the first current conductor arm is electrically conductively connectable to the first energy storage cell, and the second current conductor arm is electrically conductively connectable to the second energy storage cell.

7. The electrochemical energy storage device according to claim 6, wherein a separating area is arranged between the first energy storage cell and the second energy storage cell, the first current conductor arm on the side of the first energy storage cell extends as far as said separating area or is spaced apart therefrom by a first defined distance, and the second current conductor arm on the side of the second energy storage cell extends as far as said separating area or is spaced apart therefrom by a second defined distance.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] FIGS. 1A and 1B show an energy storage apparatus as is known from the prior art.

[0025] FIGS. 2A and 2B shows the top view and a perspective view of a current output conductor according to an embodiment of the invention.

[0026] FIGS. 3A and 3B show a further embodiment of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

[0027] FIG. 1A illustrates a partial portion of an energy storage apparatus as is known from the prior art. The energy storage apparatus has two energy storage cells 1, 2. The electrodes (not illustrated) of the energy storage cells 1, 2 can be connected to the current output conductor device 5. For this purpose, the current output conductor device 5 has a first current conductor arm 3 and a second current conductor arm 4. A current output conductor contact area is arranged on each of the current conductor arms, illustrated here as an area 3a only for the current conductor arm 3.

[0028] The energy storage cells have a width extent B, a longitudinal extent L and a thickness extent D. The complete longitudinal extent L of the energy storage cells is not illustrated here.

[0029] It can be seen in the top view in FIG. 1B that a surface normal on the cell stack or a separator contact area (not illustrated) of an energy storage cell 1 points in the direction 1.n. The surface normal 1.n is parallel to the surface normal 3.n. The surface normal 3.n is the surface normal on the area 3a which is arranged on the current output conductor 3 and is designed for contacting the electrodes (not illustrated) of the first energy storage cell 1. The surface normal 4.n should likewise be understood as the surface normal of the contact area 4a of the second current conductor arm 4. In the event of a deformation in the direction F, the current conductor arms 3, 4 can penetrate into the energy storage cells 1, 2 and can cause a short circuit therein. Further damage in the energy storage cells may occur due to a short circuit in the energy storage cells 1, 2.

[0030] FIGS. 2A and 2B illustrate an exemplary energy storage apparatus according to the invention. FIG. 2A shows a perspective partial illustration of an energy storage apparatus and FIG. 2B shows a top view of the energy storage apparatus. The energy storage cells 1, 2 are separated from each other by a separating plane T. It can be seen that, in contrast to the solution known from the prior art, the current conductor arms 3, 4 are rotated about the axis in the width direction B. The surface normal 4.n encloses the acute angle β with the normal 2.n on a separator contact area 8. The same applies for the first energy storage cell 1. The normal 3.n of the first current output conductor 3 on the current output conductor contact area 3a encloses the acute angle α here with the normal on the separator contact area 7 of the energy storage cell 1.

[0031] The first current output conductor 3 is arranged in the region of the thickness extent D of the first energy storage cell 1 and extends to the separating plane T up to the distance t.1. The second current conductor arm 4 is arranged in the thickness region of the second energy storage cell 2 and extends to the separating area T up to the distance t.2. In this embodiment, the two current conductor arms 3, 4 with the current output conductor contact areas 3a, 4a are arranged mirror-symmetrically with respect to the separating plane T. The current conductor arms are pushed into the energy storage cells 1, 2 in the deformation direction F as a type of plough or wedge, and the tendency to cause a short circuit in the energy storage cells is reduced or avoided by this geometrical shape.

[0032] FIGS. 3A and 3B illustrate a top view and a partially perspective view of an energy storage apparatus, respectively. The surface normal 1.n on the separator contact area 7 of the storage cell 1 encloses an acute angle α with the surface normal 3.n on the current output conductor contact area 3a of the first current output conductor 3. In the event of a deformation in the direction F, the tendency to produce a short circuit is reduced in comparison to the known prior art by way of the current conductor arm 3 of the current output conductor device 5.

[0033] The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.