BATTERY CELL, VEHICLE BATTERY, MOTOR VEHICLE AND METHOD FOR PRODUCING A CARRIER ELEMENT FOR AN ELECTRODE OF A BATTERY CELL

Abstract

A battery cell with at least one electrode which has a carrier element and an active layer abutting the carrier element and with an electrode material for the alternating uptake and release of ions, the carrier element electrically connecting the active layer with an electric connecting pole of the battery cell, and having an electrically conductive surface for said exchanging of electrons with the electrode material of the active layer. The electrically conductive surface of the respective carrier element is provided by electrical conducting elements, the conducting elements being provided by fibers and/or granules and/or a slotted and/or perforated film and/or film strip and/or a wad.

Claims

1. A battery cell comprising: at least one electrode which has a carrier element and an active layer abutting the carrier element and with an electrode material for the alternating uptake and release of ions, the carrier element electrically connecting the active layer with an electric connecting pole of the battery cell, and having an electrically conductive surface for exchanging electrons with the electrode material of the active layer, wherein the electrically conductive surface of the respective carrier element is provided by electrical conducting elements, the conducting elements being provided by fibers and/or granules and/or a slotted and/or perforated film and/or film strip and/or a wad.

2. The battery cell according to claim 1, wherein the fibers and/or film strips are provided as a felt or nonwoven fabric or woven fabric.

3. The battery cell according to claim 1, wherein at least some or most or all of the fibers or film strips are oriented towards the electrode terminal.

4. The battery cell according to claim 1, wherein some or all conducting elements are made of an electrically conductive material.

5. The battery cell according to claim 1, wherein some or all conducting elements are each formed by a basic element having an electrically conductive coating and/or jacket.

6. A battery with at least one battery cell according claim 1.

7. A motor vehicle with a vehicle battery according to claim 6.

8. A method for producing a carrier element for an electrode of a battery cell, wherein the carrier element is formed from a felt or nonwoven fabric or woven fabric or granules made of electrically conductive conducting elements and thereby a void for electrode material and/or an electrically conductive connecting material is left between the conducting elements in each case.

9. The method according to claim 8, wherein the conducting elements each are generated from a basic element by coating the basic element with an electrically conductive layer.

10. The method according to claim 8, wherein the electrically conductive layer is generated by metallizing the basic elements.

11. The battery cell according to claim 2, wherein at least some or most or all of the fibers or film strips are oriented towards the electrode terminal.

12. The battery cell according to claim 2, wherein some or all conducting elements are made of an electrically conductive material.

13. The battery cell according to claim 3, wherein some or all conducting elements are made of an electrically conductive material.

14. The battery cell according to claim 2, wherein some or all conducting elements are each formed by a basic element having an electrically conductive coating and/or jacket.

15. The battery cell according to claim 3, wherein some or all conducting elements are each formed by a basic element having an electrically conductive coating and/or jacket.

16. The battery cell according to claim 4, wherein some or all conducting elements are each formed by a basic element having an electrically conductive coating and/or jacket.

17. The method according to claim 9, wherein the electrically conductive layer is generated by metallizing the basic elements.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0027] Exemplary embodiments of the disclosure are described below.

[0028] FIG. 1 shows a schematic representation of a cross section through an electrode of a battery cell according to the prior art and according to the disclosure, respectively; and

[0029] FIG. 2 shows a schematic representation of an embodiment of the motor vehicle according to the disclosure with a vehicle battery according to the disclosure, in which battery cells according to the disclosure are provided.

DETAILED DESCRIPTION

[0030] The embodiments explained below are preferred embodiments of the disclosure. In the exemplary embodiments, the components described of the embodiments each represent individual features of the disclosure to be considered independently of one another, each of which further develops the disclosure independently. Therefore, the disclosure is intended to include combinations of the features of the embodiments other than those shown. Furthermore, the embodiments described can be supplemented by further features of the disclosure of those already described.

[0031] In the figures, the same reference numerals denote elements with the same function.

[0032] FIG. 1 shows two illustrations, a and b, wherein illustration b of a battery cell 10 illustrates an electrode 11 and, for comparison, illustration a shows one of a battery cell 12, as is known from the prior art, an electrode 13 with the same function as electrode 11.

[0033] In the case of battery cell 10, electrode 11 may have a carrier or a carrier element 14, on which, on one side or (as illustrated in FIG. 2) on two opposite sides, in each case an active layer 15 with an active material or electrode material 16, such as, for example, graphite, may be arranged. By means of carrier element 14, the respective active layer 15 can be electrically connected to a connection pole 17 (positive pole or negative pole) of battery cell 10.

[0034] In illustration a, functionally identical elements have the same reference numerals, but shown with apostrophes. In addition, for both illustration a, b, a scale 18 is shown, which, in this case, may be, for example, in a range of 5 to 20 micrometers, may be, for example, 10 micrometers.

[0035] In the case of battery cell 12, its electrode 13 can be a film or a sheet metal as a carrier element 14′. Correspondingly, the smooth or flat surface 19 of the carrier element, the area value of the dimension of carrier element 14′, that is to say length times width.

[0036] In the case of battery cell 10, carrier element 14 has, in contrast to carrier element 14′, conducting elements, that is to say electrically conductive elements (conducting elements 20), of which, for the sake of clarity, in FIG. 1 only a few are provided with reference numerals.

[0037] Conducting elements 20 can be, for example, metal-coated fibers or pieces of wire. Conducting elements 20 may be intertwined as felt, nonwoven fabric or woven fabric with each other. This results in voids 21 between conducting elements 20, of which, for the sake of clarity, again, only a few are provided with reference numerals. This results in an electrically conductive surface 22 on the surface of the conducting elements that in total is greater than a dimension of carrier element 14, that is, a length L and a width B which is perpendicular to the length L and perpendicular to the plane of FIG. 1. Through this electrically conductive surface 22 electrons can be exchanged between carrier element 14 and the at least one active layer 15 or pass over. This results in a lower electrical ohmic resistance in comparison to surface 19 of carrier element 14′.

[0038] FIG. 2 illustrates how electrode 11 or a plurality of such electrodes 11 can be arranged in a battery cell 10. Dots 23 indicate that several of the illustrated layer arrangements of electrodes 11 may be present in battery cell 10. Dots 24 illustrate that a plurality of battery cells 10 can be provided. Battery cells 10 may be provided in a vehicle battery 25 and (not shown) interconnected with battery terminals 26 in a known manner to operate a vehicle electrical system 28. Vehicle battery 25 may be provided in a motor vehicle 29, for example, an electric vehicle or a hybrid vehicle. Vehicle battery 25 can be configured as a high-voltage battery. The battery cell 10 may be based on Lithium-ion technology.

[0039] It is therefore proposed to replace the previous metal films made of, e.g., aluminum or copper with a metallized nonwoven fabric or woven fabric. Advantages at comparable capacity are: [0040] performance due to increase of the electrochemically active surface, [0041] increase of the mechanical strength and thus the potential rate of production, [0042] improved adhesion of the active materials (3D nonwoven fabric compared to 2D film).

[0043] Conversely, with comparable performance, a higher energy density is possible through thicker electrodes.

[0044] A nonwoven fabric or woven fabric may have several layers of nanofibers (comparable to fine-dust air filters) and may be metallized at the surface. Suitable methods for metallization include, e.g., electroplating or evaporating methods such as sputtering or PVD (Physical Vapor Deposition).

[0045] In a further method step, the nonwoven fabric can be compressed to a defined thickness in a calender in order to obtain a nonwoven fabric of homogeneous thickness. The downstream processing steps of coating and drying correspond to the previous methods.

[0046] Further possible variants are obtained by the following features: the nonwoven fabric or woven fabric may be produced from an electrically conductive, from an electrically non-conductive basic material or a mixture thereof. The nonwoven fabric or woven fabric may consist of metal fibers, which means that the coating process is not required. Depending on the application, metallization can be carried out over the entire surface or partially on the nonwoven fabric. Metallized fibers can be used, alternatively the nonwoven fabric can be metallized afterwards. The nonwoven fabric can contain directional fibers or non-directional fibers depending on the application. The nonwoven fabric may consist of a basic structure or a woven fabric (which enable an improved processing rate) and a support structure (forming the backbone of the galvanic surface).

[0047] Overall, the examples show how the performance of battery cells can be provided by increasing the electrical surface of the material of the carrier element.