Solid-state cell battery and method for manufacturing such a solid-state cell battery - Patents.com

Abstract

To facilitate the manufacture of solid-state cell batteries and overcome the drawbacks known from the prior art. A method for manufacturing a solid-state cell battery includes the following steps: - placing a carrier film on a placement table 30; - providing a first layer of collector film using a payout device 40; - providing a separator, a cathode and a further separator in a lamination process, whereby a cell stack is formed; - providing a second layer of collector film, the collector film being provided using a pay-out device 40; Including, The collector film is positioned relative to the cell stack by horizontal displacement of the rest 30 and / or by horizontal displacement of the guide rollers 42, 44, 46 of the unwinding device 40, whereby folding of the collector film is achieved.

Description

[Technical field]

[0001] The present invention relates to a solid-state cell battery according to the preambles of the independent claims and to a method for manufacturing such a solid-state cell battery. [Background technology]

[0002] To manufacture solid-state cell batteries, solid (immobile) ionically conductive separators are used, which are mostly made of ceramic materials that cannot be continuously processed or deformed (molded). Therefore, to manufacture the cell stacks of such batteries, the separators cannot be folded in a Z-shape around the anode and cathode as in conventional lithium-ion batteries with liquid electrolyte. This limitation can be explained on the one hand by the characteristic material properties of the separator material and on the other hand by the thickness of the separator.

[0003] For the production of cell stacks, preferably a monolayer stapler is used, in which the battery stack is built up layer by layer. In this case, the battery stack is made up of individual electrodes and separators, gradually increasing in height. An essential drawback of such a method is the relatively long process time during the construction of the cell stack from individual elements, due to the many stacking operations. Another drawback in the production of solid-state cell batteries using monolayer staplers is due to the fact that conventional monolayer staplers are not intended for the placement of adhesive-applied collectors. Therefore, the adhesive must be applied by an additional robot during or after the installation of the collector for a given cell type. This is particularly difficult due to the electrical conductivity of the adhesive and the aerosol-like application of the adhesive.

[0004] As in the case of conventional lithium-ion cells, the use of Z-folding allows for an increase in productivity of approximately 25% simply by reducing the number of layers during cell stack assembly. Furthermore, the Z-folding process allows for the use of collectors that are already wetted with adhesive, which can avoid several problems. In addition, the cell stack has a significantly higher mechanical stability, which greatly facilitates the operation of the otherwise relatively unstable cell stack.

[0005] At present, no solid electrodes are known to be folded into a Z-shape in a solid-state cell, and no process for the corresponding folding of the electrodes or separators is known so far due to the above-mentioned material properties of the ceramic separator material.

[0006] A method for manufacturing a solid-state cell battery, in particular a lithium-ion solid-state cell, having a first conductor layer, a second conductor layer and at least one separating layer, which are stacked into a layer stack from at least two first conductor layers and at least two second conductor layers, is known from US Pat. No. 5,399,366, wherein the first conductor layer is separated from the second conductor layer by a separating layer. The layers of the first conductor layer separated by the separating layer and / or the layers of the second conductor layer separated by the separating layer are electrically connected to each other in a layered manner, wherein at least one of the conductor layers is made of a flexible strip, which is inserted into the layer stack as a continuous layer forming at least the two first conductor layers and / or the two second conductor layers in common. A solid-state cell battery manufactured by such a method is also known from US Pat. No. 5,399,366.

[0007] Patent Document 2 discloses a method for manufacturing an energy storage device, in which a stack is formed including at least one first electrode layer, a first current collector layer, and an electrolyte layer arranged between the first electrode layer and the first current collector layer. For this purpose, a first groove in the stack is formed by the first electrode layer and the electrolyte layer, thereby forming an exposed edge portion of the first electrode layer and the electrolyte layer. Then, at least a part of the first groove is filled with an electrically insulating material, thereby covering the exposed edge portion of the first electrode layer and the electrolyte layer with the insulating material. To form the exposed edge portion of the first current collector layer, the insulating material and the first current collector layer are cut along at least a part of the first groove.

[0008] A method for producing a galvanic lithium-ion cell (battery) is known from US Pat. No. 5,399,666, in which a separator is provided to spatially separate a first electrode material from a second electrode material of the lithium-ion cell. The first electrode material is provided on a first side of the separator by a coating. Also known from US Pat. No. 5,399,666 is a galvanic lithium-ion cell produced by such a method. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] DE 102015201281 A1 [Patent Document 2] International Publication No. 2017 / 158319 [Patent Document 3] DE 102016219661 A1 Summary of the Invention [Problem to be solved by the invention]

[0010] The problem underlying the present invention is to facilitate the production of solid-state cell batteries and to overcome the drawbacks known from the prior art. [Means for solving the problem]

[0011] The problem is solved by a method for manufacturing a solid-state cell battery having a carrier film, a separator, a cathode and a continuous collector film, the method comprising the following steps: - placing a carrier film on a placement table; - providing a first layer of continuous collector film using a payout device; - providing a separator, a cathode and a further separator in a lamination process, whereby a cell stack is formed; - providing a second layer of continuous collector film, the continuous collector film being provided using a payout device; Including, The continuous collector film is positioned relative to the cell stack by horizontal displacement of the mounting table and / or by horizontal displacement of at least one guide roller of the unwinding device, whereby folding of the collector film is achieved.

[0012] It is particularly advantageous here if the solid-state cell battery does not have a solid (immobile) anode formed by lamination of a lithium anode in the cell stack, but has an anode formed in situ on the surface of the separator opposite the cathode. Alternatively, the separator can be coated with metal on the side facing the collector film. Thus, additional stacking options during the formation of the cell stack can be eliminated, which significantly accelerates the production of the solid-state cell battery.

[0013] The proposed method allows a significantly faster and easier production of solid-state cell batteries. In particular, the process time during the production of solid-state cell batteries can be reduced, since the collector film is not provided to the cell stack by an additional stacking process, but is instead supplied by a pay-out device as an endless material, in particular as a strip or film material. In particular, in such a method, only the collector film and not the separator is folded, which allows a reduction in the number of stacking operations during the formation of the cell stack by as much as 25%.

[0014] The number of stacking operations can be further reduced if a functional unit consisting of a separator and a cathode, a so-called monocell, is introduced instead of a separator and a cathode during stacking of the cell stack. If the functional unit comprises a separator, a cathode and a further separator and is configured as a so-called bicell, the number of stacking operations can be further reduced and the cycle time during the production of the solid-state cell battery can be further shortened.

[0015] Advantageous improvements and developments of the method for manufacturing a solid-state cell battery as defined in the independent claims are possible with the additional features defined in the dependent claims.

[0016] In a preferred embodiment of the invention, the collector film is provided with an adhesive layer on at least one side thereof, such that the collector film is adhered to the cell stack when the collector film is positioned against the free surface of the cell stack. By providing the collector film with an adhesive layer, the manufacturing process can be further improved and accelerated. In addition, an additional gluing process can be omitted, which increases the process reliability of the manufacturing process. Furthermore, the mechanical strength of the cell stack is increased, since the components of the cell stack are fixed to the collector film by the adhesive layer. This in particular facilitates the manipulation of the cell stack and also the lamination of further elements of the cell stack, in particular further separators, cathodes.

[0017] It is particularly advantageous here if the adhesive layer is applied to the collector film as a UV-activatable adhesive and is activated by means of a UV radiation source, in particular a UV lamp, when the collector film is positioned relative to the cell stack. A UV-activatable adhesive allows a particularly easy feeding of the collector film, since there is no risk of the collector film adhering to the guide rollers of the unwinding device during feeding.

[0018] In another preferred embodiment of the invention, the adhesive layer is applied to the collector film as a pressure-sensitive adhesive, which likewise makes it possible in an easy and inexpensive manner to supply the collector film already provided with an adhesive layer to a cell stack of a solid-state cell battery and to glue the cell stack to the collector film.

[0019] Alternatively, the adhesive layer is provided on the collector film as a reactive adhesive, which is activated upon contact with the cell stack or an activator, particularly air.

[0020] It is particularly preferred if the collector film is covered with a protective layer, in particular a protective film, which is removed when the collector film is fed to the cell stack. In this case, in particular the pressure-sensitive adhesive layer or the reactive adhesive can be covered by the protective layer until the collector film is fed directly to the cell stack by the last guide roller of the unwinding device. Thus, it is possible to minimize the risk of adhesion of the unwinding device or premature activation of the reactive adhesive.

[0021] In an alternative configuration of the method, an adhesive is applied, particularly jetted, to the cell stack such that the collector film adheres to the cell stack.

[0022] In an advantageous configuration of the method, the solid-state cell battery comprises a plurality of compartments, and the feeding direction of the collector film alternates between the different compartments, so that the serpentine folding of the collector film can be easily achieved.

[0023] In another advantageous configuration of the method, the height of the cell stack is monitored and the collector film is separated when the cell stack reaches a predetermined target height or a predetermined number of compartments, which allows separation of the collector film and its final adhesion to the cell stack to occur.

[0024] In another refinement of the method, the cell stack is covered with a carrier film after a predefined number of compartments or after a predefined stack height of the cell stack is reached, which allows easy separation of the cell stack.

[0025] Another aspect of the invention relates to an apparatus for manufacturing such solid-state cell batteries, the apparatus comprising at least one mounting table, at least one robot for constructing a cell stack, a payout device for feeding a collector film, a separation device for separating the collector film, and a control device. The control device comprises a memory unit and a computing unit, and the memory unit stores machine-readable program code. The control device performs the above-mentioned method when the machine-readable program code stored in the memory unit is executed by the computing unit of the control device. Such an apparatus allows for fast and inexpensive production of solid-state cell batteries.

[0026] Another partial aspect of the present invention relates to a solid-state cell battery including a carrier film, a first separator, a cathode, a second separator, and a continuous collector film, which is manufactured by the above-mentioned method. The manufacturing cost for such a solid-state cell battery can be reduced by reducing the stacking operations and the time consumption in the stacking process.

[0027] In one advantageous configuration of the solid-state cell battery, the collector film is a metallic film, in particular a copper film, an aluminum film or a synthetic resin film with a coating of an electrically conductive metal. The use of a metallic film as the collector film is advantageous so that the collector film is electrically conductive on the one hand and has a sufficiently high mechanical strength on the other hand. With regard to electrical conductivity and availability as an endless material, a copper film as the collector film is particularly preferred. Alternatively, a collector film made of aluminum or a collector film coated with aluminum can be used. This can only work in solid-state cells, since there is no liquid electrolyte on the anode side that can dissolve the aluminum.

[0028] The collector film may also include an additional coating having at least one additional layer, which may include, for example, a conductive metal or a separator.

[0029] The collector film can also consist of a thermoplastic or thermosetting synthetic resin coated on both sides with a conductive material, in particular copper, aluminum or a synthetic resin.

[0030] In another improvement of the solid-state cell battery, the collector film is provided with discharge contours. The discharge contours allow the weight of the collector film to be reduced. In addition, the electrical contact of the compartments can be facilitated, since between each of the discharge contours there is a free space that facilitates electrical contact. In addition, the targeted geometrical configuration of the discharge contours allows the temperature distribution in the solid-state cell to be optimized and the boundary resistance (contact resistance) to be adapted to the contact on the cathode side.

[0031] According to an advantageous configuration of the solid-state cell battery, the collector film is provided on at least one side with an adhesive layer of electrically conductive adhesive. Preferably, the collector film is provided on both sides with electrically conductive adhesive. Alternatively or additionally, electrically conductive adhesive is provided (applied) on the collector film or on the component to be joined to the collector film. To allow easy passage of electrons at the bonding points, it is advantageous for at least one side of the collector film, preferably both sides of the collector film, to be provided with electrically conductive adhesive. This can be done in particular by coating or spray application of the adhesive.

[0032] In one advantageous configuration of the solid-state cell battery, the solid-state cell battery comprises a plurality of compartments, and the collector film is arranged between the individual compartments in a serpentine or S-shape, which makes it possible to bond the endless material, in particular the film material or strip material, in a simple manner to the solid (immovable) components, in particular the separator and the cathode of the cell stack.

[0033] The various embodiments of the invention presented in this application can be advantageously combined with one another, unless otherwise stated in individual cases.

[0034] The present invention will now be described in detail with reference to the accompanying drawings, in which: FIG. [Brief description of the drawings]

[0035] [Figure 1] FIG. 1 illustrates one embodiment of a solid-state cell battery according to the present invention. [Diagram 2] FIG. 1 illustrates an installation for manufacturing a solid-state cell battery according to the present invention. [Diagram 3] FIG. 2 illustrates a method according to the invention for manufacturing such a solid-state cell battery. [Figure 4] FIG. 2 shows a flow chart for carrying out a method according to the present invention for manufacturing a solid-state cell battery. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0036] In Fig. 1, a cell stack 19 of a solid-state cell battery 10 according to the invention is shown in a schematic manner. Depending on the structure of a given solid-state cell battery 10, it is possible to fold the collector film 14 in a serpentine or S-shape around the cell stack 19 consisting of the separator 16 and the cathode 20. In this case, a metallic collector film 14 is preferably used, in particular a copper film 28, an aluminum film or a synthetic resin film coated with a conductive metal, which is wetted or coated with a conductive adhesive, in particular a conductive adhesive layer 24. By folding in a serpentine shape, an additional "pick and place" process can be avoided, which can reduce the process time during the manufacture of the solid-state cell battery 10. The collector film 14 can be formed with a discharge contour 22. The adhesive layer 24 can in particular comprise a UV-activatable adhesive 26, a pressure-sensitive adhesive (glue) 36 or a reactive adhesive 38. Although in Fig. 1 a monocell with only one compartment 34 is shown, the proposed method is particularly suitable for solid-state cell batteries 10 with several compartments 34, 35, 37. The adhesive layer 24 can be configured as a single compartment or a multi-compartment adhesive layer 24. If the collector film 14 is provided with a protective layer 52, in particular a protective film 54, the protective layer 52 is removed immediately prior to bonding of the collector film 14 with the cell stack 19.

[0037] FIG. 2 shows an installation 100 for manufacturing such a solid-state cell battery 10. The installation 100 includes at least one mounting table 30, at least one robot 50, in particular a pick-and-place system for constructing a cell stack 19, a pay-out device 40 for feeding the collector film 14 to the cell stack 19, a separation device 48 for separating the collector film 14, and a control device 60 for controlling the manufacturing process. The control device 60 includes a memory unit 62 in which a machine-readable program code 66 is stored and a computing unit 64 for executing the program code. To manufacture the solid-state cell battery 10, firstly a carrier film (base film) 12, in particular a synthetic resin base layer, is placed and fixed on the mounting table 30 shown in FIG. 2. Then the collector film 14 is transferred and / or glued to the carrier film 12. At this time, the collector film 14 can be unwound by displacing one or more guide rollers 42, 44, 46 of the unwinding device 40 or by displacing the mounting table 30, as shown in FIG. 2. Preferably, as shown in FIG. 2, the unwinding device 40 has a first guide roller 42, a second guide roller 44, and a third guide roller 46. Here, the collector film 14 is tensioned by the guide rollers 42, 44, 46. The third guide roller 46 is used to position the collector film 14 relative to the cell stack 19. In addition to the tensioning function of the collector film 14, the first guide roller 42 and the second guide roller 44 can have an additional function, in particular, the function of providing (applying) an adhesive layer or removing a protective film 54 provided on the collector film 14. In order to displace the mounting table 30, a displacement device 32 capable of displacing the mounting table 30 in the horizontal direction is provided on the mounting table 30. In a subsequent process step, the separator 16, the cathode 20 and a further separator 16 are deposited (laminated) into a cell stack 19 on the collector film 14 in a defined manner by one or more robots 50.After the battery elements are deposited, the guide rollers 42, 44, 46 move the collector film 14 moistened with the adhesive 24 onto the cell stack 19, where the collector film 14 is folded in a serpentine shape. The above process is repeated until the predetermined number of compartments 34, 35, 37 is reached. Finally, the collector film 14 is separated by a separation device 48 and awaits the construction of the next cell stack 19. Preferably, a robot 50 is present on each side of the cell stack 19 to accelerate the construction of the cell stack 19 and to improve the availability of components. To accelerate the construction of the cell stack 19, it is possible to use pre-assembled member elements with a separator-cathode composite or a separator-cathode-separator composite. The anode (metallic lithium) of the solid-state cell battery 10 can be formed in situ on the separator 16 opposite the cathode 20. The anode can therefore be part of the separator 16 and can be installed during each charge process of the solid-state cell battery 10 and removed again during each discharge process. Alternatively, the anode may be part of the collector film 14 or may be formed on the surface of the collector film facing the separator 16. Essentially, metallic lithium of the anode may be installed by an electrochemical process in the solid-state cell battery 10 according to the present invention.

[0038] The robot 50 may be equipped with a spray device 56 that applies adhesive 58 to the cell stack 19 for adhering the cell stack 19 to the collector film 14 .

[0039] 3 illustrates the flow diagram for manufacturing a solid-state cell battery 10 according to the present invention. As described above with respect to FIG. 2, in a first manufacturing step, the carrier film 12 is placed and fixed on the mounting table 30. Then, the collector film 14 is transferred and / or glued to the carrier film 12, and the corresponding separator 16 and cathode 20 are deposited on the collector film 14. Then, a second layer of collector film 14 is applied to the cell stack 19, with the feeding direction being opposite to that of the first layer of collector film 14. The feeding is controlled by the guide rollers 42, 44, 46 of the unwinding device 40.

[0040] In a further process step 2, the non-flexible components 16, 18, 20 are stacked in the cell stack 19. And in a process step 3, the mounting platform 30 is displaced downwards and / or the bottom most guide roller 46 of the unwinding device 40 is displaced upwards in order to obtain additional space for further compartments 35, 37 in the cell stack 19 of the solid-state cell battery 10.

[0041] In process step 4, a further layer of collector film 14 is deposited onto the cell stack 19 and the lowermost guide roller 46 and / or the mounting table of the unwinding device 40 are displaced horizontally to fold the collector film 14 into a serpentine shape as described above.

[0042] Further lamination of separator 16, anode 18, cathode 20 and other non-flexible battery components occurs in process step 5. In the final process step 6, once a predetermined number of compartments 34, 35, 37 has been reached or the cell stack 19 has reached a predetermined height, the collector film 14 is separated such that the free end of the collector film 14 is bonded to the surface of the overlying separator 18 in the cell stack 19.

[0043] A flow chart for manufacturing such a solid-state cell battery 10 is shown in Figure 4. Method steps <100> First, the carrier film 12, in particular a synthetic resin substrate, is placed on the support table 30 and fixed there. <110> In the method, a collector film 14 is provided in the form of a strip of material, and then the method steps <120> 3. The adhesive is adhered to the carrier film 12 in <130> In, a separator 16, a cathode 20 and a further separator 16 are laminated to the collector film 14 by one or more robots 50 so as to produce a cell stack 19. <140> In the method step 1, the mounting table 30 and / or at least one guide roller 42, 44, 46 of the unwinding device 40 is displaced in order to feed the collector film 14 again to the cell stack 19. The feeding is performed in the opposite direction to the first feeding so that the collector film 14 is folded in a meandering manner. <150> In the method step 14, the height of the cell stack 19 or the number of compartments 34, 35, 37 of the cell stack 19 is determined. When the cell stack 19 reaches its target height and / or the desired number of compartments, the method step 14 is performed. <160> In the second stage, the collector film 14 is separated from the strip material and finally adhered to the surface of the last free separator 16 . [Explanation of symbols]

[0044] 10 Solid-state cell battery 12 Career Film 14 Collector Film 16 Separator 19 Cell Stack 20 Cathode 22 Discharge contour section 24 Adhesive layer 26 UV Activatable Adhesives 28 Copper Film 30 Placement table 32 Displacement device 34 First Compartment 35 Second Compartment 36 Pressure Sensitive Adhesives 37 Third Compartment 38 Reactive adhesives 40 Payout device 42 First guide roller 44 Second guide roller 46 Third guide roller 48 Separation device 50 Robot 52 Protective layer 54 Protective Film 56 Spray Equipment 58 Adhesive 60 Control Equipment 62 Memory Unit 64 arithmetic units 66 Machine-readable program code

Claims

1. A method for manufacturing a solid-state cell battery (10) including a carrier film (12), a separator (16), a cathode (20) and a continuous collector film (14), the method comprising the steps of: - placing said carrier film (12) on a mounting table (30); - providing a first layer of said continuous collector film (14) using a payout device (40); - providing said separator (16), said cathode (20) and a further separator (16) in a lamination process, whereby a cell stack (19) is formed; - providing a second layer of said continuous collector film (14), said collector film (14) being provided using a pay-off device (40); Including, - a method for manufacturing a solid-state cell battery (10), characterized in that the continuous collector film (14) is positioned with respect to the cell stack (19) by horizontal displacement of the mounting table (30) and / or by horizontal displacement of at least one guide roller (42, 44, 46) of the unwinding device (40), whereby folding of the collector film (14) is achieved.

2. 2. The method of claim 1, further comprising providing the collector film with an adhesive layer on at least one side of the collector film, such that the collector film is adhered to the cell stack when the collector film is positioned against a free surface of the cell stack.

3. 3. The method of claim 2, wherein the adhesive layer (24) is applied to the collector film (14) as a UV-activatable adhesive and is activated using a UV radiation source when the collector film (14) is positioned against the cell stack (19).

4. The method for manufacturing a solid state cell battery (10) according to claim 2, characterized in that the adhesive layer (24) is applied to the collector film (14) as a pressure sensitive adhesive (36).

5. 3. The method of claim 2, wherein the adhesive layer (24) is applied to the collector film (14) as a reactive adhesive (38), the reactive adhesive (38) being activated upon contact with the cell stack (19).

6. 6. The method for manufacturing a solid-state cell battery (10) according to any one of claims 3 to 5, characterized in that the collector film (14) is covered with at least one protective layer (52), in particular with at least one protective film, which protective layer (52) is removed when the collector film (14) is provided to the cell stack (19).

7. 2. The method for manufacturing a solid-state cell battery (10) according to claim 1, wherein an adhesive (58) is sprayed onto the cell stack (19) to bond the collector film (14) to the cell stack (19).

8. 8. The method for manufacturing a solid-state cell battery (10) according to any one of claims 1 to 7, characterized in that the solid-state cell battery (10) comprises a plurality of compartments (34, 35, 37), and the supply direction of the collector film (14) is alternated between the different compartments (34, 35, 37).

9. 9. The method of manufacturing a solid state cell battery (10) according to any one of claims 1 to 8, characterized in that the height of the cell stack (19) is monitored and the collector film (14) is separated when the cell stack (19) reaches a predetermined target height.

10. 10. The method for manufacturing a solid-state cell battery (10) according to any one of claims 1 to 9, characterized in that the cell stack (19) is covered with the carrier film (12) after reaching a predetermined number of compartments (34, 35, 37) or after reaching a predetermined stack height of the cell stack (19).

11. 11. An installation (100) for manufacturing a solid-state cell battery (10) according to any one of claims 1 to 10, the installation (100) comprising at least one placement table (30), at least one robot (50) for constructing a cell stack (19), a payout device (40) for feeding the collector film (14), a separation device (48) for separating the collector film (14), and a control device (60) having a memory unit (62), a computing unit (64) and a machine-readable program code (66) stored in the memory unit (62), characterized in that the control device (60) is configured to perform the method according to any one of claims 1 to 8 when the machine-readable program code (66) is executed by the computing unit (64).

12. A solid-state cell battery (10) comprising a carrier film (12), a first separator (16), a cathode (20), a second separator (16) and a continuous collector film (14), characterized in that the solid-state cell battery (10) is manufactured by the method according to any one of claims 1 to 10.

13. 13. The solid-state cell battery (10) according to claim 12, characterized in that the collector film (14) is a metallic film, in particular a copper film (28), an aluminum film or a synthetic resin film coated with a conductive metal.

14. 14. The solid-state cell battery (10) of claim 12 or 13, characterized in that the collector film (14) is formed with a discharge contour (22).

15. 15. The solid-state cell battery (10) according to any one of claims 12 to 14, characterized in that the solid-state cell battery (10) includes a plurality of compartments (34, 35, 37), and the collector film (14) is arranged in a serpentine or S-shape between the individual compartments (34, 35, 37).

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