Method and device for the adhesive bonding of layers of an energy cell

Abstract

A method for producing stacked energy cells having a plurality of separator sheets and a plurality of electrodes, specifically alternately arranged anodes and cathodes, arranged between the separator sheets, wherein at least one electrode is fixed to at least one of the separator sheets by means of an adhesive bond, in which the adhesive substance for the at least one adhesive bond is applied using the gravure printing method, provides a particularly precise bonding.

Description

[0001] Method and device for adhesively bonding layers of an energy cell

[0002] The present invention relates to a method for producing stacked energy cells with a plurality of separator sheets and a plurality of electrodes arranged between the separator sheets, namely alternately arranged anodes and cathodes, wherein at least one electrode is fixed to at least one of the separator sheets by means of an adhesive connection, as well as to a device for producing stacked energy cells with a plurality of separator sheets and a plurality of electrodes arranged between the separator sheets, namely alternately arranged anodes and cathodes, wherein the separator sheets and electrodes are fed individually or in prefabricated composite units consisting of at least two components for stack formation, comprising a stacking station in which the stacks are formed from the individual components and the prefabricated composite units, comprising at least one adhesive application device,which is designed and equipped to apply adhesive to at least one of the supplied components.,

[0003] Energy cells or energy storage devices within the meaning of the invention are used, for example, in motor vehicles, other land vehicles, ships, aircraft, or even in stationary systems such as photovoltaic systems in the form of battery cells or fuel cells, where very large amounts of energy must be stored over longer periods of time. For this purpose, such energy cells have a structure consisting of a large number of segments stacked together to form a stack. These segments are each formed from alternating anode sheets and cathode sheets, which are separated from one another by separator sheets that are also in the form of segments. Various methods are known for producing the stacks. Typically, the segments are pre-cut during the manufacturing process and then placed on top of one another to form the stacks in the predetermined sequence separator - anode - separator - cathode and joined together by lamination.The four-layer stacks formed in this way are called monocells. In another process, the anode and cathode sheets are first cut from a continuous sheet and then individually placed at intervals on a continuous sheet of separator material. This subsequently formed "double-layer" continuous sheet of separator material with the applied anode and cathode sheets is then cut into segments in a second step using a cutting device. In this case, the segments are formed in a double layer, consisting of a separator sheet with an anode or cathode sheet arranged on top.If technically feasible or necessary, the continuous sheets of separator material with the anode and cathode sheets applied can also be stacked on top of each other before cutting, forming a continuous sheet with a first continuous layer of separator material with anode or cathode sheets applied on top, and a second continuous layer of separator material with anode or cathode sheets applied on top. This "four-layer" continuous sheet is then cut into segments using a cutting device, which in turn forms monocells. The individual layers or sheets are usually bonded to the layers by lamination. Bonding is extremely important, as the segments must be stacked very precisely with only a small tolerance and must not be able to shift relative to each other.The separator sheets must reliably separate the anode and cathode to prevent short circuits. Devices and methods for producing a cell stack for battery cell production are known, for example, from DE 10 2017 216 138 A1 and DE 10 2017 216 213 A1 or DE 10 2018 219 000 A1.

[0004] Laminating is an energy-intensive process, and the manufacturing costs of the laminating units are very high. Suitable materials must also be used for the lamination process. In particular, the separator must be capable of being laminated, which severely limits the choice of possible materials, especially since other requirements (e.g., low layer thickness) must also be met.

[0005] Therefore, alternative methods for attaching the layers to one another have been proposed. For example, EP 3 588 653 A1 discloses applying adhesive to the anode and cathode sheets using adhesive nozzles, thus producing sheets with bonded electrodes, which are then cut into monocells.

[0006] Applying the adhesive from the nozzles is problematic. Especially when applying the adhesive across the web's travel direction, it is difficult to achieve a clean application. The low viscosity of the adhesives used, in particular, makes precise application difficult. Controlling the process is difficult because the adhesive must be pulled over a stationary nozzle at a specified web tension. It would therefore be desirable to provide a device and method that enable adhesive application without the use of nozzles.

[0007] A further problem arises during further processing, namely when several of these monocells are to be stacked together to form the final energy cells. The stacked monocells must also be secured together to prevent slipping. This is achieved in the current technology either by lamination or by adhesive tape. Alternatively, the stack is secured with adhesive tape and, if necessary, subsequently passed through a hot press and laminated in a subsequent process. The problem with this is that a stack is created without directly securing it. Lamination and / or gluing are used to create monocells and then assemble them into an inhomogeneous stack. In some cases, attempts are made to subsequently bond (homogeneize) the entire stack.

[0008] The object of the present invention was therefore to provide a method and a device that creates homogeneous energy cells, ensures a secure fixation of the individual layers to one another, which also survives subsequent processes such as cutting and enables a secure fixation in the desired position and ensures a clean, sharp application of the adhesive.

[0009] This object is achieved in that, in a method of the type mentioned at the outset, the adhesive for the at least one adhesive bond is applied by a gravure printing process, and in that, in a device of the type mentioned at the outset, the at least one adhesive application device is a gravure printing roller.

[0010] Such a gravure roller has recesses on its outer surface for receiving and transporting adhesive. These recesses create a corresponding adhesive pattern on the layer to be coated. Different recesses can have the same or different recess volumes per surface.

[0011] This makes it possible to apply razor-sharp single or multiple adhesive dots, or any other adhesive pattern, to the electrode or, in particular, the separator. This ensures very good fixation of the electrodes and separators.

[0012] It is possible that the adhesive is applied using a gravure roller for only some of the bonded joints, while the adhesive for others is applied using a nozzle, for example. However, it is particularly advantageous if all required adhesive applications are carried out using the gravure printing process.

[0013] Particularly advantageously, anodes are fed along conveyor path A, cathodes along conveyor path B, and separator sheets are fed along conveyor paths C and D as separator webs. The two separator webs, the anodes, and the cathodes are first formed into continuous webs with cut cathode and anode sections. All connections between separators and electrodes are formed by adhesive bonding. The continuous webs are then separated into individual monocells in a subsequent step. This allows for increased production speed and offers the advantage of being able to test individual products for quality in a continuous process.

[0014] The object is further achieved in that, in a method of the type mentioned at the outset, the stack-shaped energy cells are formed by stacking a plurality of monocells, wherein the monocells are fixed to one another by means of an adhesive connection or - in the event that the energy cells are not produced via the intermediate step of forming monocells, but by alternately stacking the desired number of electrodes and separators - in that the adhesive is applied immediately before the stacking of the stack-shaped energy cells by alternately stacking separator sheets and electrodes.

[0015] "Immediately before stack formation" specifically means that the adhesive is applied to the electrode / separator sections when they are on the accelerator roller. Ideally, the adhesive is applied to the accelerator roller because this is where the products are correctly aligned and the speed can be adjusted if necessary. At certain positions on the accelerator roller, there is a standstill or a constant speed, while at others it is accelerating. The term "immediately before stack formation" also encompasses an alternative embodiment. Alternatively, the adhesive can be applied to the stack during deposit. This can advantageously be done by the deposit lever or after deposit by an additional moving device.

[0016] Finally, the object is achieved by a device of the type mentioned at the outset, which has a monocell stacking device for stacking a plurality of monocells to form the stacked energy cells, wherein the stacking device is assigned an adhesive application device, or - again in the case that the energy cells are not produced via the intermediate step of forming monocells, but by alternately stacking the desired number of electrodes and separators - which has a stacking device for forming stacked energy cells by alternately stacking separator sheets and electrodes, to which an adhesive application device is assigned.

[0017] Here, the adhesive is applied directly to the stacking wheel, i.e., directly during the stacking process. This inline bonding process allows for seamless integration of the fixation into the manufacturing process. Fixation by bonding occurs immediately when the individual layers or monocells are stacked on top of one another, eliminating the need to bridge any process steps or manage a processing time during which the stacks are stacked but not yet fixed to one another. This significantly improves the stack quality and significantly increases the reliability of the manufactured energy cells.

[0018] Particularly advantageous in this process is the application of the adhesive by means of a gravure printing process using a gravure roller. As described above, this allows for a particularly precise and precise application of the adhesive in the desired pattern.

[0019] Particular preference is given to using an adhesive with a melting point above 20°C, in particular above 30°C. Such an adhesive is solid at normal process temperatures and thus ensures immediate, firm fixation. It is heated before application. Therefore, the adhesive application device advantageously has an adjustable and controllable heater for the adhesive. "Melting point" here refers to the melting point of the adhesive, provided it is a material with a clearly definable melting point. However, many polymeric adhesives do not have a clear melting point, but rather a melting range. In the case of a melting range, "melting point" refers to the lower limit of the melting range.

[0020] The upper limit of the melting point is determined by the melting point of the separator material. The melting point of the adhesive (in the case of a melting range, the upper limit of the melting range) should always be below the melting point of the separator material. Therefore, the melting point of the adhesive is preferably at most 100°C, preferably at most 80°C, and particularly preferably at most 50°C.

[0021] The adhesive application device can apply the adhesive continuously or intermittently.

[0022] In a particularly advantageous embodiment, the adhesive is soluble in the electrolyte used for the energy cell. In this case, the adhesive is not a foreign body on the electrode that essentially "passivates" part of the electrode, i.e. the entire electrode surface is available for energy generation because the electrically active area is not reduced. This means that it is irrelevant which part of the electrode surface is covered with adhesive. If the adhesive does not dissolve in the electrolyte, it is particularly advantageous if only the smallest possible area of ​​the electrode is coated with adhesive. One should therefore always select the minimum application for the required fixation strength. If, on the other hand, the adhesive is soluble in the electrolyte, the restriction of the smallest possible application of adhesive does not apply, and it is not necessary to work with the smallest possible application of adhesive.Rather, the fixation can be improved by using a larger amount of adhesive without having to fear a loss in energy cell performance.

[0023] Preferably, the adhesive is heated immediately before application. For this purpose, an adjustable and controllable heater is assigned to the adhesive application system, in particular to the adhesive reservoir of the gravure roller.

[0024] The adhesive solidifies and thus the bonding of the materials to be bonded occurs by cooling the adhesive below its melting point. Furthermore, it is therefore preferred if the adhesive is cooled below its melting point after application, with the cooling occurring actively or passively. Depending on the melting point of the adhesive, a sufficiently long cooling section can passively cool the adhesive sufficiently due to free convection to solidify. If an even faster solidification of the adhesive is desired, the adhesive can also be actively cooled. For this purpose, the device has a cooling unit for actively cooling the applied adhesive. This advantageously has control means by means of which the cooling process can be regulated.

[0025] There are many options for applying the adhesive. Full-surface application is possible. This is preferred if, as described above, the adhesive dissolves in the electrolyte. Bonding can then be achieved over the entire surface without affecting the performance of the energy cell. In another preferred embodiment, the adhesive is applied to a portion of the electrode and / or separator. Other options include applying the adhesive in strips or dots. Partial application of the adhesive to the four corners of the electrode sheet to be bonded or to the corresponding locations on the separator is particularly preferred. Applying the smallest possible amount of adhesive is particularly preferred, as this saves material.

[0026] The adhesive can be applied to the web material in various ways:

[0027] In a preferred embodiment, the adhesive is applied continuously or intermittently to the separator film, after which the electrodes are placed on top and fixed. Fixing occurs in particular by cooling and thus solidifying the adhesive. In another preferred embodiment, the adhesive is applied continuously or intermittently to the electrode track (anode track and cathode track) and joined to the separator. In a third preferred embodiment, the adhesive is applied continuously or intermittently to the electrode sections, which are then joined to the separator.

[0028] The device according to the invention advantageously comprises control means for controlling the application of the adhesive. These can, in particular, control the application temperature and / or application quantity of the adhesive. Key parameters for the control are, in particular, the heat capacity, the thermal conductivity, the web speed of the anode, cathode, and separator webs, as well as the length of the cooling section and the cooling power. Particularly preferably, the bonding is followed by a step of pressing the bonded materials together, in which the bonded materials are bonded even more tightly to one another. For this purpose, the device according to the invention preferably comprises means for pressing the bonded materials together. Such pressing can occur without contact. This can preferably be achieved by adjusting the web tension of the endless web of the separator or by means of a directed air stream.In a preferred embodiment, the device according to the invention therefore further comprises control means for adjusting the web tension of the separator web and / or means for introducing an air flow, which are arranged downstream of the adhesive application device and the location where the respective materials are joined. In a further preferred embodiment, the means for pressing the bonded materials together are designed to contact each other, in particular as laminating rollers, preferably made of rubber, which press the bonded materials together with a defined force, or as soft brushes with which a pressure is applied.

[0029] In a further advantageous embodiment, the application is carried out using a transfer device, which can be designed, in particular, as a transfer roller. This method is used primarily when electrode and / or separator sections are to be coated with adhesive. A transfer device can also be used for application to web-like material, but this is not absolutely necessary. Rather, in this case, the application can be carried out directly via the gravure roller.

[0030] If the energy cells are manufactured by first forming monocells and then stacking them to form the energy cells, it is particularly advantageous if all layer connections—both the layers within the monocells and the interconnections between the monocells—are made using adhesive. This ensures a homogeneous bond. It is particularly advantageous to use an adhesive that dissolves in the electrolyte of the energy cell.

[0031] The present invention makes it possible to produce an energy cell without the need for lamination. If all required connections between the layers are made by adhesive, lamination can be completely dispensed with. Such a "lamination-free" process is particularly preferred because it is more energy-efficient and also ensures a homogeneous bond between all layers. Furthermore, the lamination-free process according to the invention opens up greater variability in separator materials, for which lamination capability is no longer a prerequisite. Materials that exhibit good wettability are particularly preferred as separators according to the invention; ceramic-coated separators are particularly preferred.

[0032] In principle, all solvent-free and non-aqueous adhesives with a melting point above 20°C are suitable as adhesives. In a particularly preferred embodiment, at least one compound from the group consisting of acrylates, methacrylates, SBS block copolymers, SIS block copolymers, polyurethanes, silicones, natural rubbers, synthetic rubbers, epoxy resins, polyolefin resins, and ethylene carbonate is used as the adhesive. In particular, the adhesive can be a pressure-sensitive adhesive. Ethylene carbonate is a cyclic ester with a melting point of 36°C. Ethylene carbonate is a common solvent and is used as an electrolyte in lithium-ion batteries. Due to its melting point, it is particularly well suited as an adhesive for the present application.

[0033] The dependent claims are directed to the aforementioned and other expedient and advantageous embodiments of the invention. Only particularly expedient and advantageous embodiments and possibilities are described in more detail in the following description of the exemplary embodiments illustrated in the schematic drawings. Each individual or detailed design described within an exemplary embodiment is to be understood as a structurally independent detailed example of other embodiments and designs falling within the scope of the invention that are not described or not fully described.

[0034] It shows

[0035] Fig. 1 a section of a stacking station with two stacking devices with adhesive application

[0036] Fig. 2 shows an embodiment of a monocell production device with adhesive application to the separator Fig. 1 shows a section of a stacking station 1 with two stacking devices with adhesive application device 20, feed device 2, two transfer drums 5 and a reversing drum 6 arranged between the transfer drums 5. Furthermore, the stacking station comprises two cell stacking devices 11, each with a removal device 111 and an associated depositing element 112. The removal device 111 is designed as a rotary body in the form of a drum driven to rotate and has three transfer dies 113 aligned at angles of 120 degrees to one another. The transfer dies 113 have an outer surface which in its outer dimensions corresponds at least to the outer shape of the segments 16 or can also be larger than these.The transfer punches 113 have, in their cross-section perpendicular to the rotational axis of the removal device 111, an outer contour in the shape of a circular arc, each with identical radii, so that they complement each other to form a virtual circle. Furthermore, the removal devices 111 with their transfer punches 113 are arranged and their radii are dimensioned such that, during the rotational movement, the outer surfaces of the transfer punches 113 touch the outer surfaces of the transfer drum 5 with a gap corresponding at least to the thickness of the segments 16. The rotational movement of the removal device 111 is controlled relative to the respective transfer drum 5 such that the transfer punches 113 each take over exactly one segment 16 from the transfer drum 5 during rotation.For this purpose, the movement of the removal device 111 is controlled such that the lateral surfaces of the transfer punches 113 at the point of shortest distance to the transfer drum 5, which corresponds to the transfer point I, have a circumferential speed corresponding to the circumferential speed of the segments 16 held on the transfer drum 5, and the segments 16 are ideally taken over by the transfer punches 113 without a relative speed in the circumferential direction.

[0037] Vacuum lines are provided in the webs of the transfer dies 113, which can be subjected to negative pressure and whose openings open into the end-side lateral surfaces of the webs and / or transfer dies 113. Furthermore, corresponding openings of vacuum lines capable of being subjected to negative pressure can also be provided in the lateral surfaces of the transfer drums 5. The segments 16 are then held to the lateral surfaces of the transfer drums 5 by applying negative pressure in the vacuum lines and are taken over by the removal device 111 by switching off the negative pressure in the vacuum lines of the transfer drum 5 and by switching on the negative pressure in the vacuum lines of the transfer die 113 passing through the transfer point I.

[0038] Individual separator blades or monocells with separator blades can be considered as segments 16. If the segments are monocells, the stacking device is a monocell stacking device.

[0039] The rotary movement of the removal devices 111 and thus of the transfer punches 113 is controlled such that they receive the segments 16 in a predetermined sequence from the transfer drums 5. In the present exemplary embodiment, two cell stacking devices 11 are provided, so that each of the cell stacking devices 11 receives segments 16 in a fixed sequence in a two-by-two rhythm from the feed device 2. Thus, the first removal device 111 of the first cell stacking device 11 assigned to the first transfer drum 5 receives the first segments 13 of a group of two from the first transfer drum 5 during one rotation with one of its transfer punches 113 in a rhythm. Subsequently, the segments 16 of the groups of two remaining on the first transfer drum 5 are received by the first reversing drum 6 and transferred further to the second transfer drum 5.The second cell stacking device 11 then removes the second segments 16 of the groups of two from the second transfer drum 5 in the same way using the transfer punches 113 of the second removal device 111. Since each of the removal devices 111 has three transfer punches 113, the segments 16 are removed from the feed in three groups of two by the transfer punches 113 until all segments 16 have been removed after transfer by the second transfer drum 5.

[0040] The removal devices 111 are each arranged between a transfer drum 5 and a storage member 112 and receive the segments 16 from the transfer drum 5 according to the sequence described above. The removal devices 111 are driven to rotate counterclockwise, as can also be seen from the direction of the arrow in Figure 1. While each of the segments 16 is being received from a transfer drum 5, the removal device 111 is located with one of its receiving stamps 113 in the "12 o'clock position" and passes with it through the receiving point I. This position of the removal device 111 with a receiving stamp 113 arranged in the "12 o'clock position" is also referred to in the sense of the invention as the receiving position of the removal device 111. The transfer stamp 113, which has taken over segment 16 of the previous group of four of the removal drum 5, is in this position in the “8 o’clock position”.In this takeover position, the removal device 111 rotates at a circumferential speed of the outer surfaces of the takeover punches 113 which corresponds to the circumferential speed of the segments 16 on the transfer drum 5 and takes over a segment 16 with the takeover punch 113 arranged in the “12 o’clock position”. Another takeover punch 113 is located in the “4 o’clock position”, which does not carry a segment 16 and therefore has a free outer surface, since it has just delivered a segment 16 to the depositing member 112.

[0041] The adhesive application device 20 is also provided in the "8 o'clock position." In the embodiment of Fig. 1, this consists of the gravure roller 21, the adhesive reservoir 22, and the transfer roller 23. The adhesive in the adhesive reservoir 22 is heated to 40°C using a heating device (not shown) and thus liquefied. The gravure roller 21 has depressions in the form of cups to create the desired adhesive pattern on the segment 16. The heated adhesive flows from the adhesive reservoir 22 into the corresponding cups of the gravure roller 21. These cups release the adhesive onto the transfer roller 23 in the predetermined adhesive pattern.

[0042] Transfer roller 23 is synchronized with the removal device 111 such that the transfer roller 23 has the same speed as the removal device 111 in the "8 o'clock position." In this way, the gluing pattern can be transferred from the transfer roller 23 to the segment 16 in the "8 o'clock position."

[0043] To transfer segment 16 from the transfer die 113, which is located in the "8 o'clock position" in the transfer position of the removal device 111, the removal device 111 continues to rotate until the removal device 111, with the transfer die 113 previously positioned in the "8 o'clock position," is positioned in the "6 o'clock position" and passes through transfer point II. The adhesive is thus applied in the "8 o'clock position" immediately before the stack formation, which follows transfer point II.

[0044] Transfer point II is the point of shortest distance between the outer surface of the transferring receiving punch 113 and the depositing member 112. Since the number of receiving punches 113 is odd, transfer point II can be arranged in the "6 o'clock position" opposite transfer point I in the "12 o'clock position" without two of the receiving punches 113 passing through transfer point I and transfer point II at the same time. The position of the removal device 111 with the receiving punch 113 arranged in the "6 o'clock position" is also referred to in the context of the invention as the transfer position of the removal device 111.

[0045] During this rotational movement, the removal device 111 can be decelerated to such an extent that the removal device 111 rotates at a lower peripheral speed in the transfer position to facilitate the release of the segment 16. In the transfer position of the removal device 111, the segment 16 is released from the transfer punch 113 arranged in the "6 o'clock position" to the depositing member 112.

[0046] The depositing member 112 has a receptacle 115 and a stripper 117 with a comb-like structure with a plurality of webs directed parallel to one another, the width and arrangement of which are dimensioned such that, as the removal device 111 rotates, they engage in the gap between the webs of the receiving punches 113 of the removal device 111 due to their position or through an active movement and, in the transfer point II, passively and / or actively comb out the segment 16 held thereon from the receiving punch 113 through their own movement and / or the movement of the removal device 111. The cell stack is thus formed on the receptacle 115, which is transported from there and fed to the completion of the energy cell.

[0047] Fig. 2 shows an embodiment of a monocell manufacturing device with adhesive application to the separator. Anodes are fed along a conveyor path A, cathodes along a conveyor path B, and separator sheets are fed as separator webs along conveyor paths C and D. The anodes and cathodes are first formed into continuous webs with cut cathode and anode sections.

[0048] Separator web 30 is fed along a conveyor path C and guided around deflection roller 31. Adhesive, heated and thus liquefied, is applied to a first surface of separator web 30 by the adhesive application device 21a, designed as a gravure roller. The gravure roller 21a has depressions in the form of cups arranged in a pattern corresponding to the desired adhesive pattern. The adhesive is applied by the gravure roller 21a to the separator web 30 in repeating sections according to the desired adhesive pattern.

[0049] The anode is fed along a conveyor path A, where it is separated into anode sections 50 by a cutting drum 52. The anode sections 50 are fed to the separator web 30 via an anode dispenser roller 51 and arranged on the separator web according to the adhesive pattern. Control means (not shown) synchronize the gravure roller 21a with the anode conveyor path A so that the anode sections 50 are arranged at the desired adhesive-coated locations on the separator web 30. Once the anode sections have been applied to the adhesive-coated separator web 30, the separator web passes through a cooling device 80, in which the adhesive is cooled and solidified, thus affixing the anode sections 50 to the separator web 30.

[0050] In an analogous manner, separator web 40 is fed along a conveyor path D and guided around deflection roller 41. Adhesive application device 21b, designed as a gravure roller, applies heated and thus liquefied adhesive to a first surface of separator web 40. This adhesive is the same adhesive that is also applied to separator web 30. Gravure roller 21b has depressions in the form of cups arranged in a pattern corresponding to the desired adhesive pattern. This adhesive pattern can be the same as that for separator web 30, but it can also differ. The adhesive is applied to separator web 40 by gravure roller 21b in repeating sections according to the desired adhesive pattern.

[0051] The cathode is fed along a conveyor path B, where it is separated into cathode sections 60 by a cutting drum 62. The cathode sections 60 are fed to the separator web 40 via a cathode dispenser roller 61 and arranged on the separator web according to the adhesive pattern. Control means (not shown) synchronize the gravure roller 21b with the cathode conveyor path B so that the cathode sections 60 are arranged at the desired adhesive-coated locations on the separator web 40. Once the anode sections have been applied to the adhesive-coated separator web 30, the separator web passes through a cooling device 81, in which the adhesive is cooled and solidified, thus fixing the cathode sections 60 to the separator web 40.

[0052] Further along the separator web 30 is a further adhesive application device 21c, designed as a gravure roller, which in turn applies heated and liquefied adhesive to the second surface of the separator web 30. The two separator webs, separator web 40 with cathode sections 60 and separator web 30 with anode sections 50, meet at pressure roller 90. The separator web 30 is placed with its second surface, provided with adhesive, on the surface of the cathode sections 60 located on the second separator web 40, in such a way that the centers of the anode and cathode sections 50, 60 each lie one above the other. The adhesive fixes the separator track 30 to the cathode sections and a monocell track is formed, consisting of the two separator tracks 30, 40, the anode sections 50 and the cathode sections 60.This is cut into the finished mono cells by a cutting device (not shown).

[0053] REVISED SHEET (RULE 91) ISA / EP

Claims

Claims 1. Method for producing stacked energy cells with a plurality of separator sheets and a plurality of electrodes arranged between the separator sheets, namely alternately arranged anodes and cathodes, wherein at least one electrode is fixed to at least one of the separator sheets by means of an adhesive bond, characterized in that the adhesive for the at least one adhesive bond is applied by gravure printing.

2. Method according to claim 1, characterized in that anodes are fed onto a conveying path A, cathodes onto a conveying path B, and separator sheets are fed onto separate conveying paths C and D as separator tracks (30, 40), continuous tracks with cut cathode and anode sections (50, 60) are initially formed from the two separator tracks (30, 40) and the anodes and the cathodes, wherein all connections of separators and electrodes are formed by means of adhesive bonding, and the continuous tracks are separated into individual monocells in a further step.

3. Method for producing stacked energy cells with a plurality of separator sheets and a plurality of electrodes arranged between the separator sheets, namely alternately arranged anodes and cathodes, wherein at least one electrode is fixed to at least one of the separator sheets by means of an adhesive bond, in particular according to claim 1 or 2, characterized in that the stacked energy cells are formed by stacking several monocells, wherein the monocells are fixed to one another by means of an adhesive bond.

4. Method for producing stacked energy cells with a plurality of separator sheets and a plurality of electrodes arranged between the separator sheets, namely alternately arranged anodes and cathodes, wherein at least one electrode is fixed to at least one of the separator sheets by means of an adhesive bond, in particular according to claim 1, characterized in that the stacked energy cells a method is formed by alternately stacking separator sheets and electrodes, wherein the adhesive is applied immediately before the stacking process. A method according to one or more of claims 1 to 4, characterized in that the adhesive has a melting point above 20°C, in particular above 30°C. A method according to one or more of claims 1 to 5, characterized in that the adhesive is soluble in the electrolyte used for the energy cell. A method according to one or more of claims 1 to 6, characterized in that the adhesive is heated immediately before its application. A method according to one or more of claims 1 to 7, characterized in that the adhesive is cooled after application, wherein the cooling is active or passive. A method according to one or more of claims 1 to 8, characterized in that the application is carried out by means of a transfer roller (23).A method according to one or more of claims 1 to 9, characterized in that the adhesive is applied over the entire surface, partially over the surface, or at specific points to the separator sheet, the electrode, or both. A method according to one or more of claims 1 to 10, characterized in that the bonding is followed by a step of pressing the bonded materials together. A method according to one or more of claims 1 to 11, characterized in that the stacked energy cells are produced without lamination. A method according to one or more of claims 1 to 12, characterized in that the adhesive consists of at least one compound from the group comprising acrylates, methacrylates, SBS block copolymers, SIS-, etc. Block copolymers, polyurethanes, silicones, natural rubbers, synthetic rubbers, epoxy resins, polyolefin resins and ethylene carbonate are used.

14. Device for the production of stacked energy cells with a plurality of separator sheets and a plurality of electrodes arranged between the separator sheets, namely alternately arranged anodes and cathodes, wherein the separator sheets and electrodes are fed individually or in prefabricated composite units consisting of at least two components for stack formation, comprising a stacking station (1) in which the stacks are formed from the individual components and the prefabricated composite units, comprising at least one adhesive application device (20) which is designed and configured to apply adhesive to at least one of the fed components, characterized in that the at least one adhesive application device (20) is a gravure roller (21).

15. Device according to claim 14, characterized in that the device has a conveying path A for anodes, a conveying path B for cathodes and a conveying path C and D each for separator tracks (30, 40) and further comprises an anode positioning device (51) which places the anodes on one separator track (30) for the production of an anode-separator composite unit, and a cathode positioning device (61) which places the cathodes on the other separator track (40) for the production of a cathode-separator composite unit, wherein at least one of the anode positioning device (51) and the cathode positioning device (61) is associated with an adhesive application device (20, 21a, 21b) for applying adhesive to the electrodes and / or in particular the separator, which is designed as a gravure roller (21, 21a, 21b).

16. Device according to claim 15, characterized in that the device further comprises a mono-cell manufacturing unit for the production of mono-cells from the anode-separator and cathode-separator composite comprises units and the mono-cell manufacturing unit is assigned an adhesive application unit (20) which is designed as a gravure printing roller (21c).

17. Device for producing stacked energy cells with a plurality of separator sheets and a plurality of electrodes arranged between the separator sheets, namely alternately arranged anodes and cathodes, wherein the separator sheets and electrodes are fed individually or in prefabricated composite units consisting of at least two components for stacking, comprising a stacking station (1) in which the stacks are formed from the individual components and the prefabricated composite units, comprising at least one adhesive application device (21) which is designed and configured to apply adhesive to at least one of the fed components, in particular according to at least one of claims 14 to 16, characterized in that the device has a single-cell stacking device for stacking several single cells to form the stacked energy cells.wherein the stacking device (1) is assigned the adhesive application device (20).

18. Device for producing stacked energy cells with a plurality of separator sheets and a plurality of electrodes arranged between the separator sheets, namely alternately arranged anodes and cathodes, wherein the separator sheets and electrodes are fed individually or in prefabricated composite units consisting of at least two components for stacking, comprising a stacking station (1) in which the stacks are formed from the individual components and the prefabricated composite units, comprising at least one adhesive application device (20) which is designed and configured to apply adhesive to at least one of the fed components, in particular according to claim 14, characterized in that it includes a stacking device (11) for forming stacked energy cells by alternately stacking separator sheets. and has electrodes, wherein the stacking device (11) is associated with the adhesive application device (20).

19. Device according to claim 17 or 18, characterized in that the adhesive application device (20) associated with the mono-cell stacking device or the stacking device (11) is designed as a gravure printing roller (21).

20. Device according to one or more of claims 17 to 19, characterized in that the stacking device (11) or the mono-cell stacking device has an accelerator drum (111) and that the adhesive application device (20) is associated with the accelerator drum (111).

21. Device according to at least one of claims 14 to 20, characterized in that it further comprises one or more transfer rollers (23) which are associated with the gravure printing roller(s) (21).

22. Device according to at least one of claims 14 to 21, characterized in that it has a cooling device (80) for cooling the applied adhesive.

23. Device according to claim 22, characterized in that it has control means for the cooling device (80).

24. Device according to claim 22 or 23, characterized in that it has a heating device for heating and liquefying the cooled adhesive mass.

25. Device according to claim 24, characterized in that it has control means for the heating device.

26. Device according to at least one of claims 14 to 25, characterized in that it has control means for controlling the application of the adhesive. Device according to at least one of claims 14 to 26, characterized in that it has means for compressing (90) the bonded materials.

Images