ACTIVATABLE BATTERY, ELECTRONIC IGNITER, PROCESS FOR PRODUCING AN ACTIVATABLE BATTERY AND METHOD OF USING AN UNSUPPORTED FILM IN A BATTERY

Abstract

An activatable battery includes at least one cathode, at least one anode, at least one absorptive separator layer in contact with the anode and the cathode and a liquid electrolyte separated therefrom and provided in an apparatus which liberates the electrolyte in order to activate the battery in such a way that it comes into contact with the separator layer and penetrates through the latter at least to such an extent that the electrolyte electrically connects the anode and the cathode to one another. The anode is formed of lithium or a lithium-containing alloy and the cathode includes elemental carbon and is formed of an unsupported film including carbon nanotubes or of a film formed of carbon nanotubes. An electronic igniter, a process for producing an activatable battery and a method of using a film in a battery are also provided.

Claims

1. An activatable battery, comprising: at least one cathode including elemental carbon and being formed of an unsupported film including carbon nanotubes or a film formed of carbon nanotubes; at least one anode formed of lithium or a lithium-containing alloy; at least one absorptive separator layer disposed between said anode and said cathode and being in contact with said anode and said cathode; a liquid electrolyte being separated from said anode, said cathode and said at least one absorptive separator layer; and an apparatus receiving said electrolyte and configured to liberate said electrolyte to activate the battery by causing said electrolyte to come into contact with said separator layer and to penetrate through said separator layer at least to an extent causing said electrolyte to electrically conductively connect said anode and said cathode to one another.

2. The activatable battery according to claim 1, wherein said carbon nanotubes are joined to one another only by interactions between said carbon nanotubes.

3. The activatable battery according to claim 1, wherein said film is formed of from more than 80% to 100% by weight of said carbon nanotubes.

4. The activatable battery according to claim 1, wherein said film is formed of more than 90% by weight of said carbon nanotubes.

5. The activatable battery according to claim 1, wherein said film is formed of more than 95% by weight of said carbon nanotubes.

6. The activatable battery according to claim 1, wherein said film is formed of more than 98% by weight of said carbon nanotubes.

7. The activatable battery according to claim 1, wherein said film is formed of more than 99% by weight of said carbon nanotubes.

8. The activatable battery according to claim 1, wherein said anode is a further film.

9. The activatable battery according to claim 1, which further comprises: a plurality of electrode cells each being formed of one cathode, one separator layer and one anode; said plurality of electrode cells being assembled to form a stack; and in at least two of said electrode cells, said cathode of one of said electrode cells being electrically connected to said cathode of another of said electrode cells and said anode of one of the electrode cells being electrically connected to said anode of another of said electrode cells, or in at least two of said electrode cells, said cathode of one of said electrode cells being electrically connected to said anode of another of said electrode cells.

10. The activatable battery according to claim 9, wherein: said cathode of one of said electrode cells is electrically connected to said cathode of another of said electrode cells and said anode of one of said electrode cells is electrically connected to said anode of another of said electrode cells; and said cathode and said anode of adjacent electrode cells are electrically insulated from one another by an insulator.

11. The activatable battery according to claim 1, wherein said electrolyte includes thionyl chloride and an electrolyte salt, or said electrolyte is formed of thionyl chloride and an electrolyte salt.

12. The activatable battery according to claim 11, wherein said electrolyte salt is lithium tetrachloroaluminate.

13. The activatable battery according to claim 1, wherein said separator layer is formed of a nonwoven or includes a nonwoven.

14. The activatable battery according to claim 13, wherein said nonwoven is formed of glass fibers or includes glass fibers.

15. An electronic igniter assembly, comprising an electronic igniter being supplied with electric power by the activatable battery according to claim 1.

16. A process for producing an activatable battery, the process comprising the following steps: bringing an unsupported film including carbon nanotubes or a film formed of carbon nanotubes forming a cathode into contact with an absorptive separator layer for taking up a liquid electrolyte; bringing the separator layer into contact with an anode composed of lithium or a lithium-containing alloy; providing the electrolyte separately from the anode, the separator layer and the cathode in an apparatus for liberating the electrolyte to activate the battery; using the apparatus to liberate the electrolyte by causing the electrolyte to come into contact with the separator layer and penetrate through the separator layer at least to an extent causing the anode and the cathode to be electrically conductively connected to one another by the electrolyte; and stamping or cutting the cathode from the film by using a laser beam or cutting off the cathode from the film.

17. The process according to claim 16, which further comprises: bringing the film forming the cathode into contact with the separator layer and bringing the separator layer into contact with a further film composed of the lithium or the lithium-containing alloy and forming the anode; and stamping-out or cutting-off electrode cells including the cathode, the separator layer and the anode together in a single stamping operation or cutting operation from the film, the separator layer and the further film disposed on top of one another.

18. The process according to claim 17, which further comprises: assembling a plurality of the electrode cells to form a stack; in at least two of the electrode cells, electrically connecting the cathode of one of the electrode cells to the cathode of another of the electrode cells and electrically connecting the anode of one of the electrode cells to the anode of another of the electrode cells, or in at least two of the electrode cells, electrically connecting the cathode of one of the electrode cells to the anode of another of the electrode cells.

19. The process according to claim 18, which further comprises: in at least two of the electrode cells, electrically connecting the cathode of one of the electrode cells to the cathode of another of the electrode cells and electrically connecting the anode of one of the electrode cells to the anode of another of the electrode cells; and electrically insulating the cathode and the anode of adjacent electrode cells from one another by using an insulator.

20. A method of using a film in a lithium ion battery, the method comprising the following step: using an unsupported film including carbon nanotubes or using a film formed of carbon nanotubes as an electrode in the lithium ion battery.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

[0028] FIG. 1 is a diagrammatic, vertical-sectional view of an activatable battery according to the invention;

[0029] FIG. 2 is an enlarged, fragmentary, vertical-sectional view of an electrode cell stack of the activatable battery with a diagrammatic depiction of an electrode cell; and

[0030] FIG. 3 is a view similar to FIG. 2 of an electrode cell stack of the activatable battery with a diagrammatic depiction of a process for producing the electrode cells.

DETAILED DESCRIPTION OF THE INVENTION

[0031] Referring now to the figures of the drawings in detail and first, particularly, to FIG. 1 thereof, there is seen a diagrammatic depiction of an activatable battery 10 for supplying electric power to an igniter of a projectile. When the projectile is fired, a trigger unit 18 is activated. This as a result damages an electrolyte container 16, so that an electrolyte 17 present therein can exit. The acceleration upon firing of the projectile presses an additional mass 12 against the electrolyte container 16 via a damping element 14. As a result, the electrolyte 17 is at least substantially squeezed out from the electrolyte container 16. The electrolyte 17 therefore comes into contact with respective separator layers 24 of electrode cells 21 of an electrode cell stack 20. The separator layers are permeated by the electrolyte 17 or impregnated by the electrolyte 17. An anode 22 and the cathode 26 are electrically connected to one another by the electrolyte.

[0032] When the activated battery 10 is discharged, lithium is anodically oxidized with a release of electrons to form lithium ions (Li+) which in turn react to form lithium chloride. In a plurality of reaction steps, thionyl chloride is cathodically reduced to elemental sulfur. This also forms sulfur dioxide. The overall equation can be formulated as follows:

4Li+2SOCl.sub.2.fwdarw.4LiCl+S+SO.sub.2

[0033] The reaction products which are formed cathodically deposit in intermediate spaces and channels of the carbon cathode. Sulfur dioxide partly dissolves in the electrolyte 17. Lithium chloride formed anodically deposits in crystalline form on the anode 22.

[0034] The electrode cells 21 are stacked directly on top of one another without insulation in between in the electrode cell stack 20 depicted herein, so that there is direct electrical contact between the anode 22 of one of the electrode cells 21 and the cathode 26 of the adjacent electrode cell 21 and the electrode cells 21 are thereby connected in series. The seven electrode cells 21 stacked on top of one another as depicted herein thus generate seven times the voltage of one of the electrode cells 21 in the electrode cell stack 20.

[0035] FIG. 2 diagrammatically shows the structure of one of the electrode cells 21 made up of the anode 22, the separator layer 24 and the cathode 26.

[0036] FIG. 3 diagrammatically shows a process for producing the electrode cells 21. In this case, a rolled-up lithium foil 28, a rolled-up separator layer 30 and a rolled-up CNT film 32 are each rolled off from a roll and pressed together by two pressing rollers 34 to provide a layer composite. The electrode cells 21 are stamped out from this layer composite by stamping which is indicated by an arrow. The electrode cells 21 which are thus obtained can then be assembled to form the electrode cell stack 20.

LIST OF REFERENCE NUMERALS

[0037] 10 Activatable battery [0038] 12 Additional mass [0039] 14 Damping element [0040] 16 Electrolyte container [0041] 17 Electrolyte [0042] 18 Trigger unit [0043] 20 Electrode cell stack [0044] 21 Electrode cell [0045] 22 Anode [0046] 24 Separator layer [0047] 26 Cathode [0048] 28 Rolled-up lithium foil [0049] 30 Rolled-up separator layer [0050] 32 Rolled-up CNT film [0051] 34 Pressing roller