Method for producing a battery cell

Abstract

The invention relates to a method (2) for producing a battery cell (4), in particular a pouch-type cell, comprising an electrode stack (6) and a cell housing (150) for accommodating the electrode stack (6), the electrode stack comprising a plurality of first and second current arresters (8, 10), in which the first current arresters (8) are joined together in a non-melting material-bonded manner to form a common cathode (62) and the second current arresters (10) are joined together in a non-melting material-bonded manner to form a common anode (64), in which the electrode stack (6) is inserted into two housing halves (104), wherein the cathode (62) and the anode (64) are joined together in a non-melting material-bonded manner. The pole (64) at least partially protrudes from the housing half (104), and the housing half (104) has a pre-fixed pre-sealing strip (106, 108) in the area of the cathode (62) and the anode (64), respectively. In the method, the housing half (104) is joined circumferentially to form a cell housing (150) in a material-bonded manner, and in the method, a joining process is carried out in the area of the cathode (62) and / or the anode (64) to seal the cell housing (150), in which joining process the cathode (62) and / or the anode (64) is joined in a material-bonded manner to the respective pre-sealing strip (106, 108).

Description

Technical Field

[0001] The present invention relates to a method for producing a battery cell, in particular a pouch-type cell, comprising an electrode stack and a cell housing for accommodating the electrode stack, the electrode stack comprising a plurality of first and second current arresters. The invention also relates to a device for carrying out the method and a battery cell. Background Art

[0002] Electrically or electromechanically driven or electrically or electromechanically driven motor vehicles, such as electric vehicles or hybrid vehicles, generally include an electric motor, which can drive one or two axles. To supply electrical energy, the electric motor is generally connected to a (high-voltage) battery inside the vehicle as an electrical energy storage device.

[0003] In particular, electrochemical cells are understood here and below to mean so-called secondary batteries of motor vehicles. In such (secondary) vehicle batteries, consumed chemical energy can be recovered by a charging process. Such vehicle batteries are designed, for example, as electrochemical batteries, in particular as lithium-ion batteries. To generate or provide a sufficiently high operating voltage, such vehicle batteries typically have at least one battery cell module in which a plurality of individual battery cells are connected in a modular manner.

[0004] Battery cells are designed, for example, as electrochemical (thin) layer cells. They have a layered structure comprising a cathode layer (cathode) and an anode layer (anode), as well as a separator layer (diaphragm) arranged between the cathode and anode layers. A liquid electrolyte, for example, flows through these components, which provides an ionically conductive connection or charge compensation for the components.

[0005] To produce a battery cell, for example, layers of active material or electrode material are applied to a current collector. The current collector is typically designed as a metal film, with copper films typically used for the anode layer and aluminum films for the cathode layer. The current collectors coated in this manner serve as electrodes for a stack (electrode stack). The current collectors of the electrode stack or cell stack are in electrical contact with one another to form a common anode and a common cathode, which are also referred to below as current collectors or current collectors.

[0006] In order to protect the electrode stack from the ingress of moisture and / or dirt, and on the other hand to prevent the escape of chemicals or liquid electrolyte in the event of damage to the battery cell, a cell housing is usually provided as a sheath. The cell housing is designed, for example, as an aluminum composite film with polypropylene (PP), wherein battery cells having such flexible or film-like cell housings (bags, pouches) are also referred to as pouch-type cells or soft pack cells.

[0007] With regard to the sealing of the cell housing, the electrical connection region in which the anode and cathode are led out of the cell housing is susceptible to leaks and leakages.

[0008] Especially for applications in vehicle batteries for electrically powered or electrically driven vehicles, rapid charging of the battery cells is desirable to minimize vehicle waiting times while the vehicle battery is being charged. Due to the tightness of the seal, gases formed accumulate inside the cell housing and thus cause the cell housing to increase in volume or expand. During rapid charging, a significant volume change of the battery cell occurs within a relatively short period of time, resulting in mechanical stresses in the connection area. The bonded connection between the plastic of the cell housing and the metal surface of the cathode or anode is generally relatively weak, so the resulting stresses can lead to leakage and irreversible damage to the battery cell.

[0009] In bag-type cells, to guide the current collectors out of the cell housing, as is known, for example, from DE 10 2014 019 505 A1, the current collectors are welded to metal strips, for example, using lasers or ultrasound. These metal strips are made, for example, from a nickel alloy and have adhesive strips conventionally made from polypropylene. These adhesive strips are also known, for example, as pre-sealing strips.

[0010] The adhesive strip is sealed to the cell housing by heating to 180°C. Heating or heat-sealing methods melt the polypropylene of the cell housing and adhesive strip, creating a leak-tight connection. A disadvantage is that the metal strip with the adhesive strip is a relatively expensive additional component. Furthermore, laser welding the metal strip to the current collector heats the adhesive strip, which reduces its connection to the metal strip and, therefore, its sealing. Furthermore, the metal strip increases the structural weight of the battery cell. Currently, removing the metal strip is not possible because it prevents the current collector from being directly connected to the bag.

[0011] The current arrester is welded to the current collector, for example, by means of laser welding. During laser welding, only a small surface area of the current collector is welded with a linear weld seam. Other areas of the current collector are not welded. Because this welding is only localized, this area heats up more rapidly because, during operation, all electrons of the battery current flow through this weld seam area as they enter or exit the electrode.

[0012] The resistance in the laser weld seam is many times higher than the resistance of the collector material (copper or aluminum). This means that (ohmic) power losses occur in the area of the laser weld seam. If the collector could be welded over its entire surface instead of using linear seam welding, the resistance during welding could be reduced. However, welding over the entire collector surface is not feasible because a metal strip with an adhesive strip is applied to the collector. The adhesive strip is not resistant to high temperatures due to surface welding.

[0013] Laser welding is a high-energy method. It melts highly conductive materials such as copper and aluminum. The heat generated during welding can be transferred to the active material, creating areas of high thermal conductivity on the collector.

[0014] Alternatively, it is possible to connect the current collector and the metal strip by ultrasonic welding (with adhesive strips). However, this disadvantageously results in mechanical vibrations that cause tolerance deviations in the stack and deformation of the arrester film. Furthermore, ultrasonic welding is highly dependent on the surface quality of the current collector. The presence of oxides, moisture, dirt, or oil films can significantly deteriorate the quality of the welded connection.

[0015] The connection of aluminum and copper in battery cells can cause galvanic corrosion, which results in connections between the metals that reduce the conductivity of the current collectors.

[0016] To address the aforementioned issues, for example, the tolerances in the heat-relevant areas of the collector region can be increased. This allows for greater collector lengths and thus allows laser welding to be performed at a greater distance from the active material and the adhesive strip.

[0017] It is known, for example, from WO 2012 / 157892 A2 and DE 10 2017 217 676 A1 to carry out a heat sealing method in the region of the collecting electrodes for sealing the cell housing. Summary of the Invention

[0018] The technical problem to be solved by the present invention is to provide a particularly suitable method for producing a battery cell. In particular, an alternative to laser welding of current collectors to metal strips with adhesive strips should be provided, which allows leak-proof sealing of the cell housing. The technical problem to be solved by the present invention is also to provide a particularly suitable device for carrying out the method and a particularly suitable battery cell.

[0019] According to the invention, this object is achieved with respect to the method by a method for producing a battery cell, in particular a pouch-type cell, and a device for carrying out the method, and with respect to the battery cell by a battery cell, in particular a pouch-type cell, as described below.

[0020] If method steps are described below, an advantageous embodiment of the device is formed in particular in that the device is designed to carry out one or more of these method steps.

[0021] The method according to the invention is provided and suitable and designed for producing battery cells. The battery cells are, in particular, pouch cells (or pouch batteries), pocket cells (or pocket batteries), or pouch cells (or pouch batteries). The battery cell comprises a cell housing and an electrode stack accommodated therein, the electrode stack comprising a plurality of first and second current arresters.

[0022] The electrode stack comprises a plurality of thin-film cells stacked on top of one another, each comprising a cathode layer and an anode layer, as well as a separator layer (diaphragm) arranged between the cathode and anode layers. For example, a layer of active material or electrode material is applied to a current arrester. The current arrester is designed, for example, as a metal film, with copper films being suitable for the anode layer and aluminum films for the cathode layer. A high-silicon-based anode layer is preferably used in this case to achieve a battery cell with the highest possible power density and, on the other hand, to enable rapid charging of the battery cell. The first current arrester is understood below to be, in particular, an aluminum film, and the second current arrester is understood to be, in particular, a copper film.

[0023] According to the method, a first current arrester is joined together without melting to form a common cathode, and a second current arrester is joined together without melting to form a common anode. "Without melting" or "without melting" is understood here to mean a material-bonded joining in which one or both of the joining partners does not transition to a melting phase. This means that the joining partners are largely not melted during the joining process.

[0024] A “material bond” or a “material-bonded connection” between at least two interconnected components is understood here and below in particular to mean that the interconnected components are joined at their contact surfaces by material bonding or crosslinking (for example due to atomic or molecular bonding forces) and, if necessary, by the action of additives.

[0025] Next, the contacted electrode stack is installed in the two housing halves, wherein the cathode and anode at least partially protrude from the housing halves as connection areas. Here, the housing halves each have a pre-fixed pre-sealing strip in the area of the cathode or anode.

[0026] "Pre-fixed" or "pre-fixed" is understood here in particular to mean that the pre-sealing strip is held or fixed in a pre-assembled state, ie in the delivery position or transport position. In other words, the pre-sealing strip is held in a pre-positioned position on the respective housing half.

[0027] The housing halves are joined circumferentially and materially to form a cell housing, for example by heat-sealing at a defined pressure, a defined (sealing) time, and a defined (sealing) temperature, thereby producing a circumferential, edge-side sealing seam as a joint.

[0028] To seal the cell housing, the invention provides for a joining process to be carried out in the region of the cathode and / or anode, in which the cathode and / or anode are materially joined to the corresponding pre-sealing strip. This results in a particularly suitable method for producing battery cells.

[0029] The order in which the cell housing and the pre-sealing strips are joined is not important. For example, the housing halves are first joined to form the cell housing and then the anode / cathode are joined to the corresponding pre-sealing strips. It is also conceivable, for example, to first connect the anode / cathode to the corresponding pre-sealing strips in the housing halves and then join the housing halves around the cell housing to form the cell housing.

[0030] The conjunction “and / or” is understood here and below to mean that the features connected by this conjunction can be designed both together and as alternatives to one another.

[0031] In an advantageous embodiment, the first and second current arresters are joined as cathode and anode by solid-state welding, in particular by thermocompression welding. In other words, the current collectors are connected by a solid-state welding method, such as thermocompression welding. The current collectors, i.e., the anode and cathode, are preferably adjusted to their final dimensions during the solid-state welding process.

[0032] The method according to the present invention eliminates the need for additional metal strips with adhesive strips, allowing the current collectors to be connected using a solid-state welding method (hot-press welding). This means that, unlike the prior art, the connection originates solely from the current collectors. This reduces the amount of heat introduced into the electrode stack or onto the active layers (cathode and anode layers). The solid-state welding of the current collectors forms a surface weld, not a linear seam weld as in laser welding. Therefore, compared to laser welds, contact and connection of the current arrester is achieved over a (large) surface area, which advantageously reduces ohmic heat losses during battery operation.

[0033] "Solid-state welding" or "solid-state welding method" is understood to mean, in particular, a joining method in which the joint connection is produced solely by the use of pressure or by a combination of heat and pressure. When heat is used, the temperature in this method is below the melting point of the metals to be welded. Furthermore, no additional materials are used.

[0034] Solid-state welding is understood to include, for example, diffusion welding, in which the joining partners are joined under pressure at an elevated temperature, and the components melt by solid-state diffusion. Preferably, in the method according to the invention, pressure welding or friction welding is used as solid-state welding, in which the joining regions of the metallic joining partners are heated by friction and connected under pressure.

[0035] Suitably, the first and second current arresters are cleaned before contact or before joining in a non-melting material-joining manner. In other words, the surfaces of the current arresters are free of contaminants. The surfaces of the current arresters are free of contaminants, for example, using a plasma cleaning device. In a preferred embodiment, the first and second current arresters are cleaned, in particular in an ultrasonic bath, before joining or solid welding. This ensures that the joining region is largely free of contaminants. Clean surfaces improve the quality of the joint connection and, therefore, the quality of the electrical contact.

[0036] To prevent galvanic corrosion, in a suitable embodiment, the anode and / or cathode are provided with a protective layer after the non-melting joining. In particular, tinning is applied to the copper side, i.e., the anode side, immediately after solid welding or pressure welding. In other words, the anode is provided with a tin layer as a protective layer. Alternatively, a nickel coating of the anode is also conceivable.

[0037] An additional or further aspect of the invention provides for the use of a multi-layer pre-sealing tape having a metal layer and a plastic layer and an insulating layer arranged between the metal layer and the plastic layer, wherein the metal layer faces the cathode or anode and the plastic layer faces the housing half.

[0038] Unlike the prior art, the pre-sealing tape or adhesive strip according to the present invention is not made exclusively of polypropylene. The pre-sealing tape according to the present invention comprises three base layers, which are joined together to form the pre-sealing tape, for example, using a roll lamination process. The first layer is made of metal (copper or aluminum) and has a layer thickness of, for example, approximately 0.05 mm. The second layer is made of a plastic material, such as polypropylene (PP) or polyester (PET), and has a layer thickness of, for example, 0.1 mm. To connect the metal layer to the plastic layer, a silicone-based adhesive is preferably used as the insulating layer. This insulating layer is preferably temperature-resistant up to 200°C (Grad Celsius).

[0039] In a suitable design, a metal layer adapted to the cathode or anode is used. This means that the pre-sealing strip according to the invention is provided in two types or designs. A copper layer is used as the metal layer for the anode, wherein an aluminum layer is used as the metal layer for the cathode. The metal layer is preferably made of the same material as the material of the associated collector. Suitably, the housing halves also comprise plastic material at least in part. This makes it possible to achieve a reliable and sealed material-bonded connection between the plastic layer and the housing halves on the one hand and between the metal layer and the corresponding collector on the other hand, wherein the plastic layer and the housing halves are material-bonded during a circumferential heat-sealing method, and wherein the metal layer and the corresponding collector are material-bonded in an additional joining process.

[0040] In an advantageous extended design, electromagnetic pulse welding (EMP welding) is used as a joining process for connecting the corresponding pre-sealing strip materially to the collector, which joins the metal layer to the corresponding collector material. This means that magnetic forming is performed, during which one of the joining partners is pulsed contactlessly with the help of a magnetic field and collides with the other partner. Due to the high speeds at which the joining partners collide, a material-joined connection in the solid phase is produced, as in explosion welding. EMP welding only introduces relatively little heat, so that thermal warping of the cell housing and / or the collector is essentially avoided.

[0041] The cell housing is designed, for example, as an aluminum composite film with polypropylene (PP) and / or polyester (PET). In a preferred embodiment, the housing halves are produced using a deep-drawing process, wherein the pre-sealing strip is pre-attached to the housing halves during the deep-drawing process. This means that the pre-sealing strip is directly attached to the pouch cell during the deep-drawing process.

[0042] For this reason, the pre-sealing tape is connected to the housing halves, for example, by a double-sided adhesive tape (with hot melt adhesive). For this reason, the pre-sealing tape, for example, has an additional hot melt adhesive layer on the plastic layer, the hot melt adhesive layer having a layer thickness of approximately 0.01 mm, so that the pre-sealing tape is fixed on the housing halves.

[0043] In an additional or alternative embodiment, a texture is embossed into the housing halves to pre-fix the pre-sealing strip. This means that a texture is preferably produced on the housing halves during the deep-drawing process, which improves the adhesion between the housing halves and the pre-sealing strip. In particular, in this embodiment, an additional adhesive layer with hot-melt adhesive on the plastic layer is not necessary.

[0044] The device according to the invention is intended, suitable, and configured to carry out the method described above. In this case, the embodiments described with respect to the method also reasonably apply to the device, and vice versa. This results in a particularly suitable device for producing battery cells.

[0045] The battery cell according to the invention is designed in particular as a pouch cell and is provided, for example, for use in a vehicle battery of an electrically driven or electrically drivable motor vehicle.

[0046] The battery cell comprises an electrode stack and a cell housing for accommodating the electrode stack, the electrode stack comprising a plurality of first and second current arresters. The first current arresters are joined to a common cathode in a material-bonded manner without melting, and the second current arresters are joined to a common anode in a material-bonded manner without melting, wherein the cell housing comprises two circumferentially joined housing halves, from which the cathode and anode at least partially protrude. The housing halves each comprise a pre-sealing strip in the region of the cathode and anode, which is material-bonded to the respective current collector. This results in a particularly suitable battery cell. The advantages and configurations described with respect to the method and / or the device can also be appropriately applied to the battery cell, and vice versa. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The following is a detailed description of an embodiment of the present invention based on the accompanying drawings. In the drawings, there are schematic and simplified views:

[0048] Figure 1 A flow chart showing a method according to the invention for producing a battery cell;

[0049] Figure 2 Showing the cleaning process of the method;

[0050] Figure 3 The preheating process of the method is shown;

[0051] Figure 4 A pressure welding process showing a method for contacting the collector;

[0052] Figure 5 Shows the separation process of the pressure welding process;

[0053] Figure 6 Showing the coating process of the method

[0054] Figure 7 Pre-sealing tapes for the cathode and for the anode are shown;

[0055] Figure 8 An embossing process for creating textures on the housing halves is shown;

[0056] Figure 9 The joining process for pre-fixing the pre-sealing strip on the housing halves is shown;

[0057] Figure 10 Shown are casing halves with texture and with pre-sealed tape;

[0058] Figure 11 、 Figure 12 An alternative joining process for pre-fastening the pre-sealing strip to the housing halves is shown;

[0059] Figure 13 Showing the housing halves with pre-sealing strips;

[0060] Figure 14 The heat sealing process of the method is shown;

[0061] Figure 15 A battery cell is shown in side view;

[0062] Figure 16 、 Figure 17 A joining process for material-bonding the pre-sealing strip to the current collector is shown;

[0063] Figure 18 shows an alternative embodiment of the pre-sealing tape for the cathode and for the anode; and

[0064] Figure 19 An alternative bonding process to the method for contacting the current collector is shown. DETAILED DESCRIPTION

[0065] Corresponding parts and dimensions are always provided with the same reference symbols in all figures.

[0066] Figure 1 The method according to the invention for producing a battery cell 4 (see Figure 15 ) Method 2. The following is based on Figures 2 to 19The method described in this embodiment essentially has nine consecutive method steps OP1 ... OP9. The apparatus for carrying out the method 2 or the method steps OP1 ... OP9, which is not specifically indicated, is also described below according to Figures 2 to 19 Elaborate in detail.

[0067] The battery cell 4 has an electrode stack or cell stack 6, which comprises a plurality of thin-layer cells arranged one above the other, each having a cathode layer and an anode layer, and a separator layer (diaphragm) arranged between the cathode and anode layers. For example, layers of active material or electrode material are applied to respective current arresters 8, 10. The current arresters 8, 10 are designed, for example, as metal films, copper films being suitable for the anode layer and aluminum films for the cathode layer. The current arresters 8, 10 extend beyond the electrode stack 6 at the edges. The first current arrester 8 is understood below to be, in particular, an aluminum film, and the second current arrester 10 is understood to be, in particular, a copper film.

[0068] Figure 2 The figures that follow one another show method step OP1 of method 2. In method step OP1, the surface of the arrester 8, 10 is cleaned by ultrasound. During the surface cleaning, oxides, moisture, and oily products are removed from the surface of the arrester 8, 10.

[0069] For this purpose, the device comprises an ultrasonic cleaner 12 having an ultrasonic tank 14. An ultrasonic generator 16 for frequencies up to 40 kHz (kilohertz) is arranged in the ultrasonic tank 14, wherein the ultrasonic tank 14 is filled with a liquid 18. The liquid 18 is, for example, distilled water with an alkaline solvent or an additive for cleaning oxides. During operation, the ultrasonic generator 16 generates ultrasonic waves 20, which have a maximum amplitude in the area of the immersed current arresters 8, 10. The ultrasonic waves 20 generate rapidly moving cavitation bubbles 22 in the liquid 18, which move at ultrasonic frequencies and remove dirt and oily substances from the surfaces of the current arresters 8, 10. The alkaline additive in the liquid 18 facilitates the removal of oxides on the surface.

[0070] The ultrasonic bath 14 is covered with a cover 24. The cover 24 is made of rubber and has slots for guiding the current arresters 8, 10. A cleaning roller brush 26 is arranged in the area of the cover 24. The cleaning roller brush 26 has polyamide fibers for mechanically cleaning the current arresters 8, 10. The cleaning roller brush 26 moves by contact with the current arresters 8, 10.

[0071] The electrode stack 6 is fixed by a gripper 28 in a guide plate 30 for ultrasonic cleaning. The electrode stack 6 is lowered by means of the guide plate 30, so that the current arrester 8 is immersed in the ultrasonic tank 14 through the slotted cover 24 and cleaned by the cavitation bubbles 22 and the cleaning roller brush 26. The electrode stack 6 is then moved vertically upward by means of the gripper 32 and tilted 180° by means of the hinge 34. The current arrester 10 is then immersed in the ultrasonic tank 14 and cleaned. The electrode stack 6 is accommodated in a protective cover 36 so that as little liquid 18 as possible reaches the electrode stack 6. Finally, the electrode stack 6 is removed from the guide plate 30 by the gripper 38 and guided to method step OP2.

[0072] As an alternative to method step OP1 , it is conceivable, for example, to clean the current arresters 8 , 10 by means of plasma.

[0073] Once the surface is cleaned, it is preheated in method step OP2 by means of induction heating or resistance heating in an inert nitrogen atmosphere. During resistance heating, for example, two current-carrying punches are pressed against the current arresters 8, 10. The punches are made, in particular, of graphite, titanium or tungsten.

[0074] For example, the copper anode of the current arrester 10 is preheated to 600° C. For example, the aluminum cathode of the current arrester 8 is preheated to 300° C. For this purpose, the device has a heating chamber 40 . The heating chamber 40 has a gas 42 in its interior.

[0075] The inert gas 42 is designed, for example, as nitrogen and is introduced into the heating chamber 40 at an overpressure of, for example, 15 mbar (millibar). To prevent undesired heating of the electrode stack 6, two cooling plates 44 are provided. These cooling plates 44 are pressed against the electrode stack 6 on both sides by means of grippers 46 with a clamping force indicated by arrows, thereby maintaining a temperature of a maximum of 50° C. during preheating. The cooling plates 44 are cooled by a water and glycol suspension, with the temperature control being set or adjusted depending on the water cooling rate.

[0076] The current arresters 8 , 10 are each preheated by means of a heating device 48 . The heating device 48 heats the current arresters 8 , 10 , for example, by induction or by means of a (heating) resistor.

[0077] After preheating or preheating, the current arresters 8, 10 are pressed in method step OP3 inside the heating chamber 40 by means of heated punch devices 50, 52. The punch devices 50, 52 each have a movable (pressure) punch 54 and a fixed punch 56 as mating supports. The punch 56 is supported on a base plate 58. The fixed and movable punches 54, 56 are heated by a cartridge heater 60, which is embedded in a ceramic cover or a ceramic sheath.

[0078] The punch 54 of the punch device 50 is heated in particular to a temperature between 350° C. and 600° C., for example, to 400° C., and a pressure of, for example, 4 to 6 bar is generated on the arrester 8. The punch 54 of the punch device 52 is heated in particular to a temperature between 550° C. and 750° C., for example, to 700° C., and a pressure of, for example, 6 to 7 bar is generated on the arrester 10. The temperature of the punch 54 is therefore always below the melting point of the respective arrester material. The arresters 8 are joined together to form a common cathode 62 without melting by means of the punch devices 50 , 52 , and the arresters 10 are joined together to form a common anode 64 without melting by means of the punch device 52 . In particular, pressure welding is performed, wherein the force 65 required for pressure welding is calculated according to the following formula:

[0079] Surface area of the collector * flow start pressure (approximately 50 MPa) * coefficient (5 to 10)

[0080] The current arresters 8, 10 are suitably heated to a temperature such that the flow start pressure is approximately the same, allowing the current arresters 8, 10 to be press-welded with essentially the same punch pressure. At 700°C and 550°C, the flow surface of copper and aluminum is approximately 50 MPa. If lower temperatures are used, the pressure for press welding is correspondingly increased. The factor (5 to 10) is pre-characterized using measurements and depends essentially on the cleanliness or surface purity of the current arresters 8, 10. Press welding is also performed in an inert nitrogen atmosphere of gas 42. The electrode stack 6 is cooled to below 50°C by means of a cooling plate, as in method step OP2. During press welding, the current collectors 62, 64 are held under the heated punches 54, 56 for three to five seconds.

[0081] During pressure welding, the material of current collectors 62, 64 deforms by a maximum of 5%. Due to shear strain, the remaining oxide layer breaks apart, and atomic contact is formed between the connecting metals. The materials are welded here by a solid diffusion method. Importantly, the materials do not melt during this welding process, and therefore no intermetallic connection is formed in current collectors 62, 64.

[0082] Next, after the pressure welding is completed, the joined collectors 62 and 64 are also adjusted. Figure 5 The trimming shown for the anode 64 in FIG is performed with the same stroke as in pressure welding, wherein the collector dimensions are within the tolerance limits. Since the trimming is performed at a higher temperature of the metals being joined, less cutting force is advantageously required.

[0083] The punch 54 has an integrated cutting punch 66 for separating or adjusting the anode 64. The cutting punch 66 is coupled to a pneumatic system having a spring piston 68 and a spring cylinder head 70, wherein the spring cylinder head 70 is supported on a pressure slide 72 via the punch 54. The punch 56 is designed as a mating support for the cutting punch 66 with a cutting template 74, which is equipped with a scrap drop chute 76 for the separated material.

[0084] Next, an optional method step OP4 is performed. Here, a protective coating is applied to the anode 64 as corrosion protection. Figure 6 In the illustrated method step OP4, a tin coating is applied to the copper discharger of the anode 64. For this purpose, the apparatus comprises a tin bath 78. A cartridge heater 82 is arranged in a housing 80 of the bath 78, which serves to uniformly heat the bath 78, which is heated to between 250° C. and 300° C. The bath 78 is covered by a temperature-resistant cover 84, which has a slot for the anode 64.

[0085] Optional method step OP4 improves the conductivity of the anode 64 and provides protection against galvanic corrosion. After the conditioning process, the anode or copper current collector 64 is immersed in a bath of molten tin. To this end, at the beginning of method step OP4, the electrode stack 6 is secured by grippers 86 to guide plates 88. The electrode stack 6 is lowered using guide plates 80, so that the anode 64 passes through the slotted cover 84 and is immersed in the molten tin bath 78 and coated with a protective layer having a coating thickness of approximately 0.01 mm. Tin melts at 232°C, and the molten tin bath is therefore maintained at 300°C. The coating subsequently produced during hot-dip coating consists of a very thin intermetallic layer, which initially forms at the interface between copper and tin, followed by a layer of pure tin (approximately 0.01 mm). The electrode stack 6 is then moved vertically upward using grippers 90 and tilted 180° using hinges 92. The coated anode 64 is then cooled to room temperature using cooling plates 94.

[0086] During hot-dip tinning, it is important that the rest of the current collector is cooled outside the hot-dip tinning area. In this way, no heat is transferred to the rest of the electrode. The electrode stack 6 is accommodated in a protective cover 96 for cooling the coating, similar to method step OP2.

[0087] After the tin layer has solidified, the coated anode 64 is cleaned by means of a tin particle cleaning device 98 with an air flow, wherein a suction device 100 is provided. The electrode stack 6 is then removed from the guide plate 88 by a gripper 102 and guided to method step OP6.

[0088] Hot-dip tinning is also performed in an oxygen-free environment (preferably in nitrogen) as in the previous operation. Although no tin layer is present on the aluminum, it is also advisable to cool the aluminum current collector or cathode 62 to room temperature using a cooling plate (not shown in detail). Once the electrode stack leaves the nitrogen-rich environment, the tin reduces copper oxidation.

[0089] On the one hand, the tin coating prevents oxidation of the copper on the anode 64. On the other hand, it prevents galvanic corrosion when the copper is connected to the aluminum. The tin reduces the voltage difference between the aluminum and the copper and thus slows down the galvanic corrosion.

[0090] Instead of a tin coating, a nickel coating is also conceivable, for example.

[0091] After method step OP4, the electrode stack 6 is placed in a deep-drawn bag or housing half (bag half-shell) 104. Two pre-sealing strips 106, 108 are arranged on the housing half 104 designed as a deep-drawn bag.

[0092] In method step OP5, pre-sealing tapes 106, 108 are provided. Figure 7 Two embodiments of the pre-sealing strips 106 , 108 are explained in detail.

[0093] Pre-sealing tapes 106 and 108 have a multi-layer structure comprising metal layers 110 and 112, an insulating layer 114, and a plastic layer 116. Metal layers 110 and 112 have a layer thickness of 0.05 mm. In pre-sealing tape 106, metal layer 110 is an aluminum plate, and in pre-sealing tape 108, metal layer 112 is a copper plate. Pre-sealing tape 106 is used for cathode 62, and pre-sealing tape 108 is used for anode 64.

[0094] Metal layers 110, 112 are attached to a polypropylene strip as plastic layer 116. The plastic or polypropylene layer has a layer thickness of approximately 0.1 mm. A silicone-based adhesive is provided as insulating layer 114 to secure layers 110, 112, 114. Silicone can withstand temperatures up to 200°C and also serves as an insulator. The copper used in copper layer 112 is 99.99% E-copper, and the aluminum in aluminum layer 110 is greater than 99.3% pure aluminum.

[0095] In a second embodiment, pre-sealing strips 106, 108 each have an additional layer. Layer 118 is designed as a hot melt adhesive applied to polypropylene 116. Layer 118, in particular, designed as a hot melt adhesive, has a layer thickness of 0.01 mm and has an adhesive effect on both sides. This fourth layer 118 is used to attach pre-sealing strips 106, 108 to housing half 104. This is explained below. The hot melt adhesive in layer 118 melts at approximately 100°C.

[0096] The following is based on Figures 8 to 10A first exemplary embodiment for method steps OP6 and OP7 is explained in detail, in which pre-sealing tapes 106 , 108 without layer 118 are preferably used.

[0097] In method step OP6, Figure 8 The deep-drawing process shown uses deep-drawing of an aluminum composite film into housing halves 104. For this purpose, the apparatus comprises a template 118 with a die cavity 120 serving as a negative mold for housing halves 104. The aluminum composite film is positioned as a blank on template 118 and laterally secured by sheet metal holders 122. In this embodiment, sheet metal holders 122 have inserts 124 that emboss a texture 126 into the flange surface of housing half 104. During the deep-drawing process, a punch 128 is lowered, and the film is formed into die cavity 120.

[0098] During the deep-drawing process, a texture 126 is pressed into the film, where the pre-sealing strips 106, 108 are then installed. This texture is produced using a pressing device, which is an insert 124. A negative mold for the texture 126 is created on the surface of the insert 124. As the insert 124 presses the film against the template surface, the texture 126 forms on the film or housing half 104. Once the insert 124 or the sheet metal holder 122 has applied its pressure, the (deep-drawing) punch 128 moves downward and the deep-drawing process is carried out.

[0099] exist Figure 9 , method step OP7 is shown, during which the pre-sealing strips 106, 108 are pre-fastened to the housing halves 104 and the housing halves 104 are cut. The device here has two magazines 130, from which the pre-sealing strips 106, 108 are removed. Figure 9 The magazine 130 for the pre-sealing strip 106 is shown only by way of example.

[0100] The deep-drawn bag or housing half 104 is fixed in the negative mold cavity 120 of the template 118 in method step OP7. The pre-sealing strips 106, 108 are removed from the magazine 130 and conveyed toward the collar or flange of the housing half 104. The pre-sealing strips 106, 108 are positioned precisely on the bag flange of the housing half 104 by means of the spring-loaded stop 132 of the cutting jaw 134 (see Figure 9 The cutting jaw 134 then moves downward and creates a compressive pressure on the flange and pre-sealing strips 106, 108 on the template surface (see Figure 9(right side). Pre-sealing strips 106, 108 are connected to the bag flange of housing half 104 through strong adhesion due to the texture 126 produced in method step OP6. In other words, pre-sealing strips 106, 108 are welded to the housing flange. Thereafter, cutting punch 136, designed as an upper blade, moves downward and, together with the lower blade serving as the mating support / blade 138, cuts the bag flange to the correct size. This means that method step OP7 installs pre-sealing strips 106, 108 on housing half 104 and also cuts the flange to the correct size. The separated or sheared pieces 140 are guided out via the inclined surface 142 of template 118.

[0101] exist Figure 9 In the view of FIG, for example, two upper and lower blades 136, 138 are provided on both sides of the housing half 104. It is also conceivable that the upper and lower blades 136, 138 are provided on only one side. In other words, the upper and lower blades 136, 138 can be designed optionally on one side or on both sides. It is also conceivable, for example, that when the template 118 with the lower blade 138 is moved toward the cutting jaw 134, the upper blade 136 is not provided.

[0102] The installation of pre-sealing strips 106, 108 is temporary. This pre-fixing only ensures that pre-sealing strips 106, 108 do not move from their position on the bag flange during transport to further processing. Pre-sealing strips 106, 108 do not yet have a leak-tight connection with the bag surface to achieve a leak-proof seal. The leak-proof sealing of pre-sealing strips 106, 108 with the two housing halves 104 and collecting electrodes 62, 64 is achieved in method step OP8.

[0103] Figure 10 The two housing halves 104 are shown in a perspective view. The upper housing half 104 is shown after method step OP6, wherein the texture 126 has been pressed into the flange of the housing half 104, while the lower housing half 104 is shown after method step OP7, wherein the pre-sealing strips 106, 108 have been pre-fixed and the flange has been cut.

[0104] The following is based on Figures 11 to 13 A second exemplary embodiment for method steps OP6 and OP7 is explained in detail, in which a pre-sealing tape 106 , 108 having a layer 118 is preferably used.

[0105] exist Figure 11 and Figure 12, an alternative embodiment of method steps OP6 and OP7 for positioning and pre-fixing the pre-sealing strips 106, 108 is shown. In this embodiment, a transport guide structure 144 is provided from the silo 130 to the flange. The plate holder 122 has a stop 132. The spring-loaded punch 136 is supported on the deep-drawing punch 128. In addition, the upper blade of the cutting punch 136 is supported on the punch 128 by means of a gas pressure spring 148. In an alternative embodiment not shown, rollers can also be used for the pre-sealing strips 106, 108 instead of the silo 130, and the pre-sealing strips 106, 108 are supplied as continuous material on the rollers and separated or split by the blades.

[0106] exist Figure 11 and Figure 12 In the illustrated embodiment, the aluminum laminate film rests on the surface of template 118. The sheet holder 122, acting as a blank holder, is lowered downward and presses the film against the surface of template 118. The pre-sealing strips 106, 108 are positioned from a hopper 130 via a transport guide 144 at a stop 132, and a punch 128, acting as a deep-drawing punch, is moved downward. The punch 146 is used to connect the pre-sealing strips 106, 108 to the housing half 104, and a cutting device (cutting punch 136, mating support 138) is used to separate the flange. The first deep-drawing process is performed by the deep-drawing punch 128 as the film is deformed in the die cavity 120. Approximately 1 mm before the lower dead center of the punch 128, the pre-sealing strips 106, 108 are pressed onto the housing half 104 as a layer 118, and the flange is cut to its final dimensions. The flange texture 126 is omitted here, since the hot melt adhesive layer 114 is already connected to the flange of the housing half 104 under slight pressure.

[0107] Therefore, Figure 11 and Figure 12 In the embodiment of FIG. 1 , the deep drawing of the housing halves 104 , the final cutting of the bag flange and the mounting of the pre-sealing strips 106 , 108 on the bag flange are essentially performed in one working step.

[0108] The fixing or pre-fixing of the pre-sealing strips 106, 108 on the bag flange by means of the layer 118 is temporary and ensures that the pre-sealing strips 106, 108 do not move from their position on the bag flange during transport to other operations. The pre-sealing strips 106, 108 do not yet have a fixed connection to the surface of the housing half 104 for leak-tight sealing.

[0109] Figure 13 In the perspective view, the Figure 11 and Figure 12Housing half 104 after method step OP6, in which the pre-sealing strips 106, 108 were pre-attached and the flanges were cut. The pre-sealing strips 106, 108 are fixed to the bag film of housing half 104 via a layer of adhesive 118. The adhesive is activated only by pressure. This initially creates a transport-safe connection between the pre-sealing strips 106, 108 and housing half 104. In a subsequent process, the pre-sealing strips 106, 108 are heated, and a cohesive connection is formed between the pre-sealing strips 106, 108 and housing half 104.

[0110] Figure 14 Method step OP8 is schematically shown, in which the electrode stack 6 is inserted between two housing halves 104 provided with pre-sealing strips 106, 108. Subsequently, the housing halves 104 are brought into contact in the region of the edge flanges and are joined or sealed in a material-bonded manner by means of a heat sealing method. During the heat sealing process, a temperature of not more than 180°C and pressure are applied to the housing halves 104. The pressure is Figure 14 By means of pressure and temperature, the polypropylene of the two housing halves 104 melts. The melting and re-hardening of the polypropylene achieves a leak-free, all-around sealing of the housing halves 104, wherein a single cell housing 150 is formed (see Figure 15 ).

[0111] As in Figure 15 It can be seen relatively clearly that the electrode stack 6 is completely accommodated in the cell housing 150, wherein only the anode 64 and the cathode 62 protrude from the cell housing 150. The electrode stack 6 is arranged essentially in one half of the cell housing 150, wherein the other half acts as a free space or gas pocket 152 in order to accommodate gases formed during operation as a buffer volume.

[0112] The heat sealing process creates a circumferential sealing edge 154 by a material-bonded connection of the flanges of the housing halves 104. In the region of the pre-sealing strips 106, 108, a material-bonded connection 156 between the housing halves 104 and the plastic layer 116 is achieved.

[0113] Figure 16 and Figure 17 The process is shown in cross section before method step OP9 (see Figure 16 ) and after (see Figure 17) in the area of the anode 64 of the collector 64. In method step OP9, the metal layer 112 of the pre-sealing tape 108 is welded or connected to the metal anode 64 in a material-jointed manner. Welding is achieved in particular by electromagnetic pulse welding (EMP welding). The EMP welding technique is preferred because it does not cause a temperature increase and produces a localized weld between the metal layers 112, 64 by atomic-to-atomic contact. In the EMP welding method, the magnetic pulse causes the metal layer 112 of the pre-sealing tape 108 to move at a high speed in the direction of the collector 64. The metal layer 112 is thereby welded to the collector 64, thereby forming a leak-free connection between the metal layers 112, 64. In Figure 17 The integrally bonded connection 158 achieved thereby is shown in FIG. 1 by means of a line.

[0114] Therefore, plastic layer 116 of pre-sealing strips 106 , 108 is particularly designed and suitable and provided for heat-sealing connection with the plastic of housing half 104 , and metal layers 110 , 112 of pre-sealing strips 106 , 108 are particularly designed and suitable and provided for EMP welding with collecting electrodes 62 , 64 .

[0115] Alternatively, it is also possible to use an external moving device which moves at a relatively high speed and, by means of collision, produces a weld between the pre-sealing strip 108 and the collecting electrode 64. The external device is moved by an induced magnetic field.

[0116] Ultrasonic welding is also a viable alternative to EMP welding. Ultrasonic welding can also connect polypropylene. Using ultrasonic welding avoids the need for heat sealing. Ultrasonic welding connects the housing halves 104 to each other, to the plastic layer 116, and to the metal layer 112 of the pre-sealing strips 106 and 108 and the current collectors 62 and 64. It is important to test the weld strength using vibration loading after ultrasonic welding.

[0117] Method steps OP8 and OP9 can be interchanged, for example. In other words, the order of OP8 and OP9 can be reversed, and EMP welding can be performed first to connect pre-sealing strips 106 , 108 to current collectors 62 , 64 in a material-bonded manner, and then a heat sealing method can be performed to connect housing halves 104 in a material-bonded manner.

[0118] In the case of battery cells 4 having a liquid electrolyte, the liquid electrolyte is preferably filled into the gas bag 152 during method step OP8 or OP9 before the cell housing 150 is completely closed and sealed.

[0119] The following is based on Figure 18Further alternative embodiments for method step OP9 are explained in detail. In this case, a conductive adhesive layer 160 is applied to the metal layers 110 , 112 of the pre-sealing strips 106 , 108 . Figure 18 Embodiments of pre-sealing tapes 106 , 108 are schematically shown with a layer 118 (right side) and without a layer 118 (left side).

[0120] Conductive adhesive layer 160 is made, for example, of acrylate with carbon fiber fillers. The conductive adhesive melts during heat sealing of housing halves 104 and, after hardening, creates a strong connection between metal layers 110, 112 and the corresponding current collectors 62, 64. If this bonding method is used, pre-sealing tapes 106, 108 have four or five layers. First, a 0.02 mm thick layer of acrylate-based conductive adhesive is applied as layer 160, followed by a 0.05 mm thick copper / aluminum metal layer as metal layers 110, 112, followed by a 0.02 mm thick silicone-based adhesive as insulating layer 114, followed by a 0.05 mm thick polypropylene layer as plastic layer 116, and finally, optionally, a hot melt adhesive layer 118 with a layer thickness of 0.02 mm.

[0121] The acrylate-based adhesive of layer 160 preferably softens at 170°C, so that the adhesive can withstand higher temperatures than the heat sealing temperature of 180°C. Acrylate adhesives are pressure-based adhesives, which means that they connect the components by applying pressure. The pressure is applied during the heat sealing process. If higher temperatures are required during heat sealing, silicone-based adhesives can be used. Silicone-based adhesives with a thickness of 0.02 mm can withstand temperatures of no more than 200°C. If there is no filler material (such as carbon or graphite / silver or other metals), both acrylate adhesives and silicone adhesives can be used as insulators between the metal layer on the pre-sealing tapes 106, 108 and the collectors 62, 64.

[0122] Adhesives based on epoxides (with or without conductive components) can also be used. These adhesives usually have to be cured at higher temperatures. The temperatures are specified for heat sealing.

[0123] exist Figure 19, an alternative joining method for joining the current arresters 8, 10 to the current collectors 62, 64 in a material-bonded manner without melting is shown. In this case, the current arresters 8, 10 are first cleaned of contaminants in a first method step OP1' using an ultrasonic cleaning device. Subsequently, in a method step OP2', the current arresters 8, 10 are immersed in an adhesive bath 162 and provided with a conductive adhesive layer. Excess adhesive residues are removed using an air flow from a blower device 164. Subsequently, in a method step OP3', pressure is applied to the stacked current arresters 8, 10 using a pressure device 166, thereby joining the current arresters 8, 10 via the adhesive layer. Subsequently, in a method step OP4', the adhesive layer is cured using a heating device 168, for example at 150° C., thereby joining the current collectors 62, 64 in a material-bonded manner. Figure 19 The joining method according to method steps OP1 ′ to OP4 ′ replaces, for example, method steps OP1 to OP3 of method 2 .

[0124] The method 2 according to the invention eliminates the need for separate metal strips for connecting the current collectors 62 , 64 , thereby advantageously reducing the production costs of the battery cells 4 . Furthermore, no cost-intensive and energy-intensive laser welding is performed.

[0125] When the current collectors 62 and 64 are joined, the current arresters 8 and 10 do not melt. Therefore, no metal-to-metal connection is formed during joining. The conductivity (or electrical conductivity) after welding is as good as that of the base metal. This helps reduce power losses during charging and discharging of the battery cell 4.

[0126] The arrester membranes of the current arresters 8 and 10 are ultrasonically cleaned to remove dirt, oxide particles, and grease particles. This surface cleanliness makes the subsequent weld or joint connection stronger. The weld strength is as good as the weld strength of the base metal.

[0127] Instead of linear welding, as in laser welding, the method described involves surface welding via hot-press welding. Consequently, during operation, electrons can flow over a much larger surface area, both inside and outside the battery cell 4. This results in a lower heating of the collectors 62, 64. The electron transfer rate can be very high, which facilitates ultra-fast charging.

[0128] The welding and adjustment (or trimming) of the collecting electrodes 62 , 64 are carried out in particular in the same machine and in a single pass. This reduces the space requirement of the process and the costs of the cutting machine.

[0129] The copper current collector 64 is coated with tin to prevent oxidation. This improves conductivity and also reduces galvanic corrosion when connecting copper to aluminum.

[0130] Hot-press welding and tinning are performed, and the closed container of the device is filled with nitrogen. This prevents oxide formation on the copper and aluminum. The aluminum is preferably not coated with tin. Aluminum forms a stable oxide layer over time. This oxide formation can be prevented by coating the aluminum with a conductive epoxy-based adhesive as a protective layer before it leaves the nitrogen-filled machine chamber.

[0131] A leak-free connection (no helium leaks) is formed between the housing halves 104 and the current collectors 62 , 64 . This is particularly advantageous when the battery cells 4 experience significant expansion and contraction during charging and discharging, particularly when using silicon-based anodes.

[0132] The pre-sealing strips 106, 108 are attached to the housing halves 104 during the deep-drawing process. No additional machinery is required to attach the pre-sealing strips 106, 108 to the cell housing 150. The pre-sealing strips 106, 108 rest precisely on the flanges of the housing halves 104. Cutting or adjusting the deep-drawing process and inserting the pre-sealing strips 106, 108 into the housing halves 104 are performed in the same process. This reduces operating costs and increases precision.

[0133] The claimed invention is not limited to the aforementioned embodiments. Those skilled in the art may also derive other variations of the invention within the scope of the disclosed claims without departing from the technical solution of the claimed invention. Furthermore, in particular, all individual features described in conjunction with the various embodiments may be combined in various ways within the scope of the disclosed claims without departing from the technical solution of the claimed invention.

[0134] Therefore, the embodiment of the pre-sealing strips 106 , 108 is inventive in itself and is therefore an independent invention.

[0135] List of Reference Numerals

[0136] 2 Methods

[0137] 4 battery cells

[0138] 6 Electrode stack

[0139] 8 current discharger (cathode)

[0140] 10 Current discharger (anode)

[0141] 12 Ultrasonic Cleaner

[0142] 14 Ultrasonic bath

[0143] 16 Ultrasonic generator

[0144] 18 liquid

[0145] 20 Ultrasound

[0146] 22 Cavitation Bubbles

[0147] 24 Cover

[0148] 26 Cleaning Roller Brush

[0149] 28 Grabber

[0150] 30 guide plate

[0151] 32 Grabber

[0152] 34 hinges

[0153] 36 Protective cover

[0154] 38 Grabber

[0155] 40 Heating Chamber

[0156] 42 Gas

[0157] 44 cooling plates

[0158] 46 Grabber

[0159] 48 Heating device

[0160] 50, 52 punch device

[0161] 54, 56 punch

[0162] 58 foundation plate

[0163] 60 Cartridge Heater

[0164] 62 cathode, collector

[0165] 64 anode, collector

[0166] 65 Strength

[0167] 66 Cutting Punch

[0168] 68 Spring piston

[0169] 70 Spring Cylinder Head

[0170] 72 Press the slider

[0171] 74 Cutting Template

[0172] 76 Waste drop chute

[0173] 78 Molten Pool

[0174] 80 shell

[0175] 82 Cartridge Heater

[0176] 84 Cover

[0177] 86 Grabber

[0178] 88 guide plate

[0179] 90 Grabber

[0180] 92 hinge

[0181] 94 cooling plate

[0182] 96 protective cover

[0183] 98 Tin particle cleaning device

[0184] 100 Suction device

[0185] 102 Grabber

[0186] 104 shell halves

[0187] 106 pre-sealing tape (cathode)

[0188] 108 pre-sealing tape (anode)

[0189] 110, 112 metal layers

[0190] 114 insulation layer

[0191] 116 plastic layer

[0192] 118 Template

[0193] 120 cavity

[0194] 122 board holder

[0195] 124 Inserts

[0196] 126 Textures

[0197] 128 Punch

[0198] 130 Silo

[0199] 132 Stop

[0200] 134 Cutting Jaw

[0201] 136 Cutting Punch

[0202] 138 Matching support

[0203] 140 separators

[0204] 142 bevel

[0205] 144 Transport guide structure

[0206] 146 Punch

[0207] 148 Gas Pressure Spring

[0208] 150 single cell shell

[0209] 152 Airbag

[0210] 154 Sealed Edges

[0211] 156 connections

[0212] 158 connections

[0213] 160th floor

[0214] 162 Adhesive Pool

[0215] 164 Fan Equipment

[0216] 166 Pressure equipment

[0217] 168 Heating device

[0218] OP1…OP9 Method and Steps

[0219] OP1'…OP4' method steps

Claims

1. A method (2) for producing a battery cell (4), the battery cell comprising an electrode stack (6) and a cell housing (150) for accommodating the electrode stack (6), the electrode stack comprising a plurality of first and second current arresters (8, 10), In the method, the first current arrester (8) is joined together in a material-bonded manner without melting to form a common cathode (62), and the second current arrester (10) is joined together in a material-bonded manner without melting to form a common anode (64), In the method, an electrode stack (6) is inserted into two housing halves (104), wherein: The cathode (62) and the anode (64) at least partially protrude from the housing half (104), and the housing half (104) has a pre-fixed pre-sealing strip (106, 108) in the region of the cathode (62) and the anode (64), respectively, so that the pre-sealing strip is held in a pre-positioned position on the respective housing half. In the method, the housing halves (104) are joined circumferentially and materially to form a cell housing (150), and In the method, a joining process is carried out in the region of the cathode (62) and / or anode (64) to seal the cell housing (150), in which the cathode (62) and / or anode (64) is joined in a material-bonding manner to the respective pre-fixed pre-sealing strip (106, 108), wherein the active material layer or the electrode material layer is applied to the first current arrester or the second current arrester, respectively, A multi-layer pre-sealing tape (106, 108) is used, comprising a metal layer (110, 112) and a plastic layer (116) as well as an insulating layer (114) arranged between the metal layer and the plastic layer, wherein the metal layer (110, 112) faces the cathode (62) or the anode (64) and the plastic layer (116) faces the housing half (104). Wherein, the battery cell is a bag-type cell.

2. The method (2) according to claim 1, characterized in that The first and second current arresters (8, 10) are joined to form a cathode (62) and an anode (64) by means of solid welding.

3. The method (2) according to claim 2, characterized in that The first and second current arresters (8, 10) are joined to form a cathode (62) and an anode (64) by means of thermocompression welding.

4. The method (2) according to claim 1, characterized in that The first and second current arresters (8, 10) are cleaned in an ultrasonic bath (14) before joining.

5. The method (2) according to claim 1, characterized in that The anode (64) and / or cathode (62) are provided with a protective layer.

6. The method (2) according to claim 1, characterized in that A metal layer (110, 112) adapted to the cathode (62) or the anode (64) is used.

7. The method (2) according to claim 1, characterized in that Electromagnetic pulse welding is used as a joining process for connecting the cathode (62) and / or the anode (64) to the corresponding pre-sealing strip (106, 108) in a material-bonding manner.

8. The method (2) according to claim 1, characterized in that The housing halves (104) are produced by means of a deep-drawing process, wherein the pre-sealing strips (106, 108) are pre-fixed on the housing halves (104) during the deep-drawing process.

9. The method (2) according to claim 1, characterized in that A texture (126) is embossed into the housing halves (104) to pre-secure the pre-sealing strips (106, 108).

10. A device for carrying out the method (2) according to one of claims 1 to 9.

11. A battery cell (4) comprising an electrode stack (6) and a cell housing (150) for accommodating the electrode stack (6), the electrode stack comprising a plurality of first and second current dischargers (8, 10), -in, The first current arrester (8) is joined to form a common cathode (62) in a material-bonded manner without melting, and the second current arrester (10) is joined to form a common anode (64) in a material-bonded manner without melting, wherein the cell housing (150) comprises two housing halves (104) joined circumferentially and integrally to each other, from which the cathode (62) and the anode (64) at least partially protrude, wherein the housing halves (104) each comprise a pre-sealing strip (106, 108) in the region of the cathode (62) and anode (64), said pre-sealing strip being materially bonded to the cathode (62) or anode (64), wherein the pre-sealing tape (106, 108) is a multi-layer pre-sealing tape having a metal layer (110, 112) and a plastic layer (116) and an insulating layer (114) arranged between the metal layer and the plastic layer, wherein the metal layer (110, 112) faces the cathode (62) or the anode (64) and the plastic layer (116) faces the housing half (104), -Wherein, the battery cell is a pouch-type cell.

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