CN111095647A

CN111095647A - Method for producing an electrode arrangement, electrode arrangement and battery cell comprising at least one electrode arrangement

Info

Publication number: CN111095647A
Application number: CN201880058901.2A
Authority: CN
Inventors: J.普勒尔; A.林克
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2017-09-12
Filing date: 2018-08-30
Publication date: 2020-05-01
Anticipated expiration: 2038-08-30
Also published as: KR102616553B1; CN111095647B; KR20200051751A; DE102017216101A1; WO2019052819A1

Abstract

A method for manufacturing an electrode arrangement (10) is proposed. The method comprises the following steps: in a first step, a first separator foil (12) is provided. Subsequently, the adhesive is applied to the first separator foil (12) in a first predetermined first coating pattern, wherein a first adhesive coating (16) is formed. Subsequently, the adhesive is at least partially age-hardened. Next, an electrode unit (20) is provided and the electrode unit (20) is placed on the first separator foil (12), wherein the electrode unit (20) includes a first active material layer (22), a current collector (24), and a second active material layer (26). The electrode unit (20) is placed on the first separator foil (12) such that the first active material layer (22) is next to the first separator foil. Subsequently, the adhesive is applied a second time according to a second predefined coating pattern, wherein a second adhesive coating (18) is formed, which is at least partially located on the first adhesive coating (16). The adhesive applied during the second application is at least partially age-hardened. Subsequently, a second separator foil (14) is provided and applied to the exposed side of the electrode unit (20), wherein the second separator foil (14) is connected to the first separator foil (12) by means of an adhesive which is applied during the first application and during the second application. Other aspects of the invention relate to an electrode arrangement (10) manufactured according to the method and to a battery cell comprising such an electrode arrangement.

Description

Method for producing an electrode arrangement, electrode arrangement and battery cell comprising at least one electrode arrangement

Technical Field

The invention relates to a method for producing an electrode arrangement, wherein a first separator foil is provided, an electrode unit is placed on the first separator foil, a second separator foil is placed on the exposed side of the electrode unit, and the two separator foils are connected to one another by means of an adhesive or a polymer. Other aspects of the invention relate to an electrode arrangement manufactured according to the method and to a battery cell comprising at least one such electrode arrangement.

Background

Electrical energy may be stored using a battery pack. In this case, the chemical reaction energy is converted into electrical energy in the battery. Here, the primary battery pack can be discharged only once. The discharge is irreversible and the primary battery cannot be recharged. And the secondary battery pack, also called a secondary battery, can be recharged. Hereinafter, the term battery pack is used not only for a primary battery pack but also for a secondary battery pack, following common usage.

Lithium ion batteries are known in the prior art and are characterized by a high energy density. A lithium ion battery essentially comprises a cathode, an anode, a separator disposed between the anode and the cathode, and an ion-conducting electrolyte. The separator has the following tasks: the anode and cathode are electrically isolated from each other, wherein ionic conduction across the separator can be achieved.

From US 2015/0140394 a1 a method for producing a battery is known, in which a frame region is defined on a surface of an electrically conductive substrate, on which frame region an adhesive is at least partially applied, wherein an inner region enclosed by the frame region is substantially free of adhesive. Cathode material is coated onto the inner region. Next, the cathode current collector is arranged such that there is an electrically conductive connection between the cathode material and the cathode current collector, wherein the cathode current collector is arranged such that it protrudes beyond the area provided with the binder. An electrolyte material is coated onto the cathode material, the electrolyte material being electrically insulating but capable of conducting ions. Next, an anode material is applied to the electrolyte material, wherein a cathode current collector is electrically conductively connected to the anode material and protrudes beyond the substrate. Finally, the substrate with the layers arranged thereon is folded, wherein the battery formed here is sealed with the applied adhesive.

From KR 2004-0079533 an apparatus for the continuous production of battery cells is known, in which the separator material is unwound from a roll, the surface of the separator is coated with an adhesive, the electrode plates are placed on the separator and the adhesion between the separator and the electrode plates is established by means of the action of heat.

To manufacture the membrane bag, two membrane foils may be bonded to each other. Here, there are the following problems: the height of the bond must be similar to the height of the electrode disposed between the two membrane layers. In the known method, the height-to-width ratio of the adhesive bond is limited, so that a relatively large volume of the battery cell is occupied by the adhesive, which does not contribute positively to the energy storage.

Disclosure of Invention

A method for manufacturing an electrode arrangement is proposed. The method comprises the following steps: in a first step, a first separator foil is provided. Next, the adhesive is applied to the first separator foil in a first predefined first coating pattern, wherein a first adhesive coating is formed. Subsequently, the adhesive is at least partially age-hardened. Next, an electrode unit is provided and placed on the first separator foil, wherein the electrode unit includes a first active material layer, a current collector, and a second active material layer. The electrode unit is placed on the first separator foil such that the first active material layer is in close proximity to the first separator foil. Subsequently, the adhesive is applied a second time in accordance with a predefined second coating pattern, wherein a second adhesive coating is formed, which is at least partially located on the first adhesive coating. Preferably, the first coating pattern and the second coating pattern are selected to be the same. The adhesive applied during the second application is at least partially age-hardened. Next, a second separator foil is provided and placed on the exposed side of the electrode unit, wherein the second separator foil is connected to the first separator foil by means of an adhesive which is applied at the first application and at the second application.

The thickness of the first adhesive coating and of the second adhesive coating, respectively, immediately after application, preferably corresponds to the thickness of the first or second active material layer of the electrode unit or is preferably selected to be less thick. Thus, it is preferred that: the thickness of the first adhesive coating layer before the step after the first coating is performed is in a range of 80% to 120% of the thickness of the first active material layer. Also, it is preferable that: the thickness of the second adhesive coating layer before the step after performing the second coating is in a range of 80% to 120% of the thickness of the second active material layer. Particularly preferably, a thickness in the range from 100% to 120% of the thickness of the first or second active material layer is selected for the first adhesive coating and/or for the second adhesive coating.

The first and/or second application of the material can be effected in one layer or in a plurality of layers, respectively. In the case of the application of a plurality of layers, the same coating pattern is preferably used for each of these layers, so that the individual layers of the adhesive coating overlap.

If the coating is realized in the form of multiple layers, the previously applied layers of adhesive can be at least partially age-hardened after each of these layers has been applied. It is also conceivable: such intermediate age hardening is only performed when two or more layers have been applied. Such intermediate age hardening may be performed, for example, every two to five layers.

The coating pattern used to apply the adhesive preferably comprises one or more continuous lines of adhesive. Alternatively or additionally, the coating pattern used may comprise individual adhesive dots, which are arranged, for example, along a straight line.

By means of said one or more continuous adhesive lines and/or by means of said individual adhesive dots, an outer area is defined on the first separator foil, which outer area is provided for a connection between the first separator foil and the second separator foil. The inner area on the first separator foil is used for placing the electrode unit and is free of adhesive. Preferably, the inner region is implemented consecutively. The inner region can be embodied, for example, as a rectangle, wherein the outer region at least partially surrounds the inner region.

Especially when the first diaphragm foil is provided in the form of an endless material, the inner area is preferably defined as a coherent strip-shaped area on the material web representing the first diaphragm foil. The outer regions can be designed in particular discontinuously and be embodied in the form of two strips, each of which adjoins one side of the inner region, so that, viewed along the width of the material web, a first outer region, an inner region and a second outer region are arranged. In this embodiment, one or more continuous lines of adhesive can be applied to each of the first outer region and the second outer region, wherein the lines of adhesive extend in the transport direction of the material web, wherein each of the first outer region and the second outer region comprises at least one continuous line of adhesive. In the case of a coating pattern comprising individual adhesive dots, these adhesive dots can be arranged in particular along a straight line, wherein this straight line preferably extends in the transport direction of the material web. The first outer region and the second outer region each comprise at least one straight line along which the respective adhesive dot is applied.

The one or more continuous adhesive lines preferably have a thickness in the range of 10 to 400 μm. Here, the ratio of the width to the thickness is preferably in the range of 0.5:1 to 2: 1.

The thickness of the adhesive is defined in a direction which runs perpendicular to the surface of the first separator foil and corresponds to the stacking direction during the production of the electrode arrangement. The width of the continuous adhesive line is defined in a direction perpendicular to the thickness and perpendicular to the direction of the line along which the adhesive coating is realized.

When the adhesive is applied in the form of individual adhesive dots, these adhesive dots preferably have a thickness in the range of 10 μm to 400 μm. The diameter of such adhesive dots is preferably in the range of 10 μm to 400 μm. The diameter of the adhesive dots is here relative to a plane which corresponds to the plane of the first diaphragm foil. Here, the ratio of the diameter to the thickness is preferably in the range of 0.5:1 to 2: 1.

A pattern characterizing the adhesive coating in the form of individual adhesive dots or continuous adhesive lines is called a coating pattern.

Preferably, the electrode unit further comprises a conductor tab connected to the current collector, which conductor tab, after being placed on the first separator foil, protrudes beyond the first separator foil and, if necessary, lies at least partially on the adhesive coated by the first adhesive coating. By means of the conductor webs, electrical contacting of the electrode units is possible.

Preferably, after the second separator foil is placed, the previously applied adhesive is allowed to continue to age harden in a subsequent step. In the case of this further age hardening, the adhesive applied in the preceding step is preferably fully age hardened.

Preferably, the binder to be coated is a polymer.

Preferably, the adhesive to be applied is an adhesive which can be hardened by means of electromagnetic radiation, in particular UV radiation. Accordingly, it is preferable that: at least partial curing of the adhesive and further age curing are achieved by the action of UV radiation. In particular, the UV radiation is electromagnetic radiation having a wavelength in the range of approximately 200nm to 380 nm. An example of a binder which hardens by UV radiation is an acrylate, such as Vitralit 4731-VT from Panacol or AD491 from Delo. Another example is light-cured epoxy glue, such as KL6006 from Best corporation.

Alternatively to this, for example, an adhesive that is age-hardened by the action of heat may be used. In this case it is preferred that: at least partial hardening and/or further hardening is achieved by the action of heat.

Hot melt adhesives can be used which are processed in the heated state and age-hardened by cooling. Examples for this are hot-melt adhesives based on olefins, such as Polyethylene (PE) or polypropylene (PP). Suitable hot melts are, for example, Technomelt AS4206 from Henkel.

In the case of a coating in the form of a continuous line of adhesive, the adhesive is preferably applied with a dispenser from which the adhesive is continuously released. In the case of coatings in the form of individual adhesive dots, it is preferable to use an application head which can release individual adhesive drops in a targeted manner as required. Such coating heads are also referred to as spray applicators or sprayers.

The electrode units used for manufacturing the electrode device are preferably electrode units suitable for manufacturing lithium ion batteries. In particular, it relates to electrode units suitable as cathodes or anodes for lithium ion batteries.

The electrode unit designed as an anode preferably comprises: a current collector, for example consisting of copper; and a lithium-containing active material for the first active material layer and/or for the second active material layer. For example, metallic lithium is used as an active material of the anode. Other examples of suitable active materials for the anode besides pure lithium are graphite, silicon and modified graphite.

In the case of a cathode for manufacturing a lithium ion battery, the current collector is preferably made of aluminum and the first active material layer and/or the second active material layer includes a cathode material that can reversibly intercalate and retransfer lithium ions. Examples of suitable active materials for the cathode are, inter alia, metal oxides, such as NCA (lithium nickel cobalt aluminate), NCM (lithium nickel cobalt manganate).

The separator foil is embodied such that it functions as an electrical insulation, but is permeable to lithium ions. Suitable materials for the separator foil include, for example, porous plastic films, such as those based on polyethylene or polypropylene. Also suitable are, in particular, ceramic-coated polyethylene or polypropylene films.

As the electrolyte, for example, a liquid electrolyte containing, for example, lithium hexafluorophosphate (LiPF 6) which is a lithium conductive salt dissolved in an organic solvent can be used.

The invention also relates to an electrode arrangement which is manufactured by means of one of the described methods. Depending on the choice of electrode unit, the electrode means is a cathode or an anode for a battery cell accommodated in a separator bag. Accordingly, the electrode arrangement can be combined into a galvanic cell by combining the electrode arrangement comprising the cathode as electrode unit with the anode and the electrolyte and being accommodated in a housing. It is also possible that: an electrode assembly comprising an anode as an electrode unit is combined with a cathode and an electrolyte and contained in a housing. It is also possible to produce electrode stacks in which one of the described electrode arrangements, which have electrode units enclosed between the separator foils, is alternately stacked with one other electrode each. In one embodiment, the electrode unit arranged between the two separator foils is embodied as a cathode, such that the electrode arrangement is stacked alternately with the anode in each case, while in another embodiment, the anode is accommodated as an electrode unit between the two separator foils, such that the electrode arrangement is stacked alternately with the cathode.

Another aspect of the invention relates to a battery cell comprising at least one of the described electrode arrangements. The electrode arrangement may be combined with other electrodes and with an electrolyte, among other things.

These battery cells can be used in particular in conjunction with electric vehicles, in particular hybrid vehicles, or also for electrically driven tools.

THE ADVANTAGES OF THE PRESENT INVENTION

With the proposed method, an electrode arrangement can be simply manufactured, wherein the electrode unit is enclosed between two membrane foils. The two diaphragm foils are bonded to one another in this case, so that a diaphragm bag is formed. In order to achieve an optimal membrane bag, the adhesive used to connect the two membrane foils should be applied such that the thickness of the adhesive substantially corresponds to the thickness of the electrode unit accommodated between the two membrane foils. In the case of conventional adhesive coatings, for example in the form of continuous adhesive lines or adhesive strips or adhesive drops, the width of the adhesive lines or strips is at least as great as the thickness of the adhesive lines or strips. In the case of the usual coating of the adhesive bead, the following applies correspondingly: the diameter of the adhesive drop is at least as large as its thickness. Therefore, in order to achieve the desired thickness of the adhesive coating, a relatively large amount of space of the battery cell is occupied by the adhesive. The power density of the battery cell is reduced thereby, because the binder does not contribute positively to the energy storage.

In the proposed method, however, provision is made for: the adhesive is applied in at least two steps, wherein the adhesive is at least partially age hardened between the first application and the second application and the adhesive is at least partially disposed on the first adhesive coating when the adhesive is applied for the second application. Thus, according to the invention: at least two adhesive layers are applied in total at least by a first application and a second application, wherein preferably the same application pattern is used in each case and at least two adhesive layers are at least partially stacked together. In a preferred, ideal case, the respective individual layers of adhesive overlap without offset. Since the first adhesive coating is already at least partially age-hardened before the second application, the first adhesive coating does not dissolve and the first adhesive coating is dimensionally stable. If now one adhesive layer is applied in each case on the first adhesive coat and on the second adhesive coat, a total of two adhesive layers is applied and in this way a total thickness of adhesive can be achieved which is much greater than the width of the continuous adhesive line or the diameter of the adhesive dot. For example, in the case of a total of two layers, a thickness to width ratio or a thickness to diameter ratio of 2:1 may be achieved.

In a further preferred variant of the method, the adhesive of the plurality of layers is applied in each case at the first application and/or at the second application. In this way, the thickness-to-width or thickness-to-diameter ratio can also be further improved, so that adhesive coatings of large thickness are achieved with a smaller width or diameter ratio. For example, in the case of a width or diameter of 10 μm to 400 μm, a thickness in the range of 10 μm to 400 μm can be achieved. The ratio of the achievable thickness to the width of the adhesive line or the ratio of the achievable thickness to the diameter of the adhesive dot is for example in the range of 0.5:1 to 10: 1.

The amount of binder required for a defined thickness of the binder coating can be significantly reduced compared to conventional binder coatings in which the entire binder amount is applied as a single layer, thereby providing more space for active material in the battery cell and thereby advantageously improving the power density of the corresponding battery cell.

In embodiments in which the respective coating pattern of the adhesive comprises at least one continuous line of adhesive, the electrode unit can also be sealed at its edges by means of the adhesive. In this case, the coated adhesive serves as a sealing material which otherwise has to be arranged separately at the edges of the electrode unit. By sealing the electrode units at these edges, the properties of the battery cell comprising the electrode arrangement may be improved, since, for example, lithium plating, in which case the metallic lithium is above the active material of the electrode, is thereby prevented or at least reduced.

Furthermore, the provision of adhesive seams in the form of continuous adhesive lines may reduce the migration of particles through the battery, thereby further improving the reliability of the battery cell. Another advantage that can be seen is: the adhesive seams give the electrode arrangement additional stability.

Drawings

Embodiments of the invention are illustrated in the drawings and are further described in the following description.

Wherein:

fig. 1 shows a schematic perspective view of a first embodiment variant of the method;

fig. 2 shows a schematic view of a first embodiment variant of the method from above;

fig. 3 shows a schematic cross-sectional view of a first embodiment of an electrode arrangement;

fig. 4 shows a schematic cross-sectional view of a second embodiment of the electrode arrangement;

fig. 5 shows a schematic perspective view of a second embodiment variant of the method; while

Fig. 6 shows a schematic view of a second embodiment variant of the method from above.

Detailed Description

In the following description of embodiments of the invention, identical components and elements are denoted by the same reference numerals, wherein repeated descriptions of these components or elements are omitted in individual cases. The figures only present the subject matter of the invention schematically.

Fig. 1 schematically shows a first embodiment variant of the method according to the invention, wherein fig. 1 is a perspective view.

In fig. 1 can be seen: the first membrane foil 12 is transported in a transport direction 40. The first membrane foil 12 is provided in the form of an endless material, which is for example rolled up on a roll and unwound for processing. In the first embodiment variant shown in fig. 1, the first diaphragm foil 12 is divided into three strip-shaped regions, wherein along the width of the first diaphragm foil 12, i.e. in a direction perpendicular to the transport direction 40, the first diaphragm foil 12 has a first outer region 52, an inner region 54 and a second outer region 56 in that order. Here, the first outer region 52 and the second outer region 56 are regions in which adhesive coating is to be achieved. The interior region 54 is free of adhesive.

In order to carry out the first adhesive coating 16, two first applicators 30 are provided, by means of which the continuous adhesive lines 48 are applied in each case in the first outer region 52 and in the second outer region 56. Behind these first dispensers 30, viewed in the transport direction 40, first light sources 32 are arranged, in each case, for the first outer region 52 and for the second outer region 56. UV light is emitted by the first light source 32, which is suitable for partially age hardening the applied adhesive. The respective adhesive lines 48 are partially age hardened by means of the first light source 32, so that they are stable in shape. In this case, shape stabilization is understood as: the continuous adhesive line 48 applied by the first dispenser 30 does not melt, i.e. the ratio of the thickness of the adhesive line 48 to the width of the adhesive line 48 does not change. However, the partially age-hardened adhesive is not fully age-hardened so that the adhesive can be joined with subsequently applied adhesive lines 48. The continuous line of adhesive 48 applied by the first dispenser 30 is the first adhesive coating 16.

After the adhesive lines 48 have been partially age-hardened, seen in the transport direction 40, the electrode unit 20 is placed on the inner region 54 of the first separator foil 12. The electrode unit 20 has a first active material layer 22, a current collector 24, and a second active material layer 26, for which reference is made to fig. 3 and 4. In the embodiment shown in fig. 1, the electrode unit 20 further comprises a conductor tab 28 electrically connected to the current collector 24 of the electrode unit 20. Here, the conductor tab 28 projects beyond the first diaphragm foil 12 and is therefore located on the adhesive line 48 or the first adhesive coating 16 applied by means of the first dispenser 30.

The electrode unit 20 is located entirely within the interior region 54 on the first separator foil 12, except for the protruding conductor tab 28, such that the first active material layer 22 of the electrode unit 20 is directly connected to the first separator foil 12.

After the electrode unit 20 has been placed, seen along the transport device 40, the adhesive is applied a second time by means of a second dispenser 31. This second coating is again carried out so that continuous lines of adhesive 48 are released, wherein these continuous lines of adhesive form the second adhesive coating 18. The second adhesive coat 18 is realized according to the same pattern as for the first adhesive coat 16, so that the continuous adhesive line 48 released by the second dispenser 31 is directly on the continuous adhesive line 48 released by the first dispenser 30. The second adhesive coating 18 is applied to the conductor tab 28 only where the conductor tab 28 is located on the first adhesive coating 16 or on the adhesive line 48 that is released by the first dispenser 30.

After the second application of the adhesive, a partial curing of the adhesive ensues, as viewed in the transport direction 40, wherein for this purpose a second light source 33 is provided both for the first outer region 52 and for the second outer region 56. The second light source 33 also emits UV light which is suitable for partially age hardening the applied adhesive.

The continuous line of adhesive 48 applied by the second dispenser 31 is also dimensionally stable after partial age hardening by the second light source 33, but can be connected to the underlying continuous line of adhesive 48 and to the subsequently applied second separator foil 14.

After partial ageing hardening by means of the second light source 33, seen in the transport direction 40, the second separator foil 14 is provided and, using the deflection roller 38, is placed on the electrode unit 20 and on the

adhesive coating

16, 18 at the first outer region 52 and at the second outer region 56. Here, a connection is intermediately established between the first separator foil 12 and the second separator foil 14 by the first adhesive coating 16 and the second adhesive coating 18.

Preferably, the second diaphragm foil 14 is also provided in the form of an endless material, which may be present, for example, in a rolled-up manner and which is unwound for processing.

The electrode arrangement 10 thus obtained can be combined with other electrode arrangements for further processing into galvanic cells, wherein for this purpose the manufactured electrode arrangement 10 is divided, for example, into individual pieces, which each comprise a single electrode unit 20 embedded between two separator foils 12, 14, or the electrode arrangement 10 can be folded along folding lines, which each lie between two electrode units 20.

Optionally, the applied adhesive may be fully age hardened immediately upon application of the second separator foil 14. For this purpose, viewed in the transport direction 40, a third light source 34 can be arranged for each of the first outer region 52 and the second outer region 56, said third light source emitting UV light which is set up for completely curing the adhesive.

In other embodiments in which instead of an adhesive that is age-hardened by means of UV light, an adhesive that is age-hardened by means of heat generation is used, a heat source can be arranged instead of the

light sources

32, 33, 34, respectively. Such a heat source can be designed, for example, as an IR radiator.

Fig. 2 shows a production method of the first embodiment variant schematically shown in fig. 1 in a view from above. As is evident in the illustration in fig. 2: in the embodiment variant shown, both the first adhesive coating 16 produced by the first dispenser 30 and the second adhesive coating 18 produced by the second dispenser 31 are produced according to the same coating pattern, so that the continuous adhesive lines 48 applied by the

respective dispensers

30, 31 are stacked.

The coated adhesive lines 48 are at the first outer region 52 and at the second outer region 56. The inner region 54, which is located between the first outer region 52 and the second outer region 56, is free of adhesive. The electrode unit 20 is located entirely on the first diaphragm foil 12 in the inner region 54, except for its conductor tab 28.

Fig. 3 shows a cross-sectional view of the electrode device 10 according to the first embodiment. Here, the illustration of fig. 3 is incomplete, showing only that portion of the electrode assembly 10 that includes a portion of the first outer region 52 and the inner region 54.

From the illustration in fig. 3 it can be seen that: an electrode unit 20 including a first active material layer 22, a current collector 24, and a second active material layer 26 is located on the first separator foil 12, wherein the first active material layer 22 of the electrode unit 20 is directly connected to the first separator foil 12. Here, the first active material layer 22 is located only in the inner region 54 on the first separator foil 12.

The first adhesive coating 16, which has a thickness d and a width b, can be seen in the visible first outer region 52. Here, the thickness d, which is the same as the thickness of the first active material layer 22, is slightly smaller than the width b. The thickness d of the adhesive coating in the electrode unit shown in fig. 3 may be different from the thickness that exists immediately after the coating is performed. Especially in the case of adhesive coatings having a thickness greater than the thickness of the active material layer, the adhesive is deformed by further adhesive coatings and/or by putting on the second separator foil 14, wherein the thickness of the first adhesive coating 16 or the second adhesive coating 18 is adapted to the total thickness of the electrode unit 20 by increasing the respective width.

The conductor tab 28 of the electrode unit 20 protrudes beyond the first separator foil 12 and is located on the first adhesive coating 16 in the cross-sectional view in fig. 3.

A second adhesive coating 18 is arranged on the side of the conductor tab 28 facing away from the first adhesive coating 16, wherein the thickness d of the second adhesive coating 18 in turn corresponds to the thickness of the second active material layer 26.

The second separator foil 14 is directly connected to the second active material layer 26 of the electrode unit 20 and is also covered with the second adhesive coating 18 in the stacking direction of the electrode device 10, so that the adhesion of the first separator foil 12 to the second separator foil 14 is achieved by means of the first adhesive coating 16 and the second adhesive coating 18.

Fig. 4 shows a second embodiment of the electrode device 10 according to the invention. In contrast to the first embodiment of the electrode device 10 described with reference to fig. 3, in the second embodiment of fig. 4 the first adhesive coating 16 and the second adhesive coating 18 are embodied in the form of a first layer 42 and a second layer 43, respectively. By means of the multilayer application of the adhesive, the first adhesive coating 16 or the second adhesive coating 18 has a total thickness D, which is composed of the thickness D of the

respective layer

42, 43. The total thickness D is much greater than the width b of the first adhesive coating 16 or the second adhesive coating 18. The specification of the thickness of the

individual layers

42, 43, the total thickness D of the first adhesive coating 16 or the second adhesive coating 18 and the width b relates in each case to the state after the second separator foil 14 has been placed.

Fig. 5 shows a second embodiment variant of the method in a schematic perspective view.

In contrast to the first embodiment of the method described with reference to fig. 1, the first application and the second application of the adhesive are not carried out using the dispensing heads 30, 31, but by means of the application heads 44, 46. By means of the first application head 44, a first adhesive coating 16 is applied to the first diaphragm foil 12 not only at the first outer area 52 but also at the second outer area 56, wherein the adhesive is released in the form of a pattern which thus comprises adhesive dots 50 arranged along a straight line. Viewed in the transport direction 40, after the first application, a first partial aging hardening follows, wherein the first light source 32 is used again for this purpose. After partial age hardening, the electrode unit 20 is placed on the first separator foil 12 with the first active material layer 22 again fully located in the interior region 54 and directly connected to the first separator foil 12. The conductor tab 28 again protrudes beyond the first separator foil 12 and may be located on one or more of the adhesive dots 50 of the first adhesive coating 16 if desired.

Immediately after the electrode unit 20 is placed, the adhesive is applied a second time, which is carried out by means of a second application head 46. The same coating pattern is also used for the second application, so that the adhesive dots 50 of the second adhesive coating 18 are applied congruent with and thus lie on the adhesive dots 50 of the first adhesive coating 16. The adhesive is subsequently partially aged a second time, for which purpose a second light source 33 is used again. Next, the second separator foil 14 is placed, wherein the second separator foil 14 is pressed again by means of the deflection roller 38 against the second active material layer 26 of the electrode unit 20 and the adhesive present in the first outer region 52 or the second outer region 56.

If necessary, the adhesive is subsequently fully cured using a third light source 34.

Fig. 6 shows a second embodiment variant of the production method in a schematic view from above. In this view it can be well seen that: adhesive dots 50 are applied to the first outer region 52 and the second outer region 56, respectively, such that the inner region 54 is free of adhesive. In this case, the electrode unit 20 is located completely on the first separator foil 12 in the inner region 54, except for its conductor web 28.

The present invention is not limited to the embodiments described herein and the aspects emphasized therein. Rather, within the scope of protection specified by the claims, a plurality of variants are possible, which are within the scope of processing of the person skilled in the art.

Claims

1. A method for manufacturing an electrode arrangement (10), the method comprising the steps of:

a. providing a first separator foil (12);

b. applying adhesive onto the first separator foil (12) a first time according to a predefined first coating pattern, wherein a first adhesive coating (16) is formed;

c. at least partially age-hardening the adhesive applied in step b);

d. providing an electrode unit (20) and placing the electrode unit onto the first separator foil (12), wherein the electrode unit (20) comprises, in this order, a first active material layer (22), a current collector (24) and a second active material layer (26), and wherein the first active material layer (22) is immediately adjacent to the first separator foil (12);

e. applying the adhesive a second time according to a predefined second coating pattern, wherein a second adhesive coating (18) is formed, which is at least partially located on the first adhesive coating (16);

f. at least partially age hardening the adhesive applied in step e); and also

g. Providing a second separator foil (14) and placing the second separator foil on the exposed side of the electrode unit (20), wherein the second separator foil (14) is connected with the first separator foil (12) by means of the adhesive applied in steps b) and e).

2. The method according to claim 1, characterized in that the thickness of the first adhesive coating (16) before the step after step b) is carried out is in the range of 80 to 120% of the thickness of the first active material layer (22); and/or the thickness of the second adhesive coating (18) is in the range of 80% to 120% of the thickness of the second active material layer (26) before the step after step e) is carried out.

3. Method according to one of claims 1 or 2, characterized in that, in the first application and/or in the second application, the adhesive is applied in the form of one layer (42) or in the form of a plurality of layers (42, 43), respectively, wherein in the application of a plurality of layers (42, 43) the same coating pattern is used for each layer (42, 43) such that the layers (42, 43) overlap.

4. A method according to any one of claims 1 to 3, wherein the coating pattern comprises one or more continuous lines (48) of adhesive.

5. The method according to one of claims 1 to 4, characterized in that the coating pattern comprises individual adhesive dots (50).

6. Method according to one of claims 1 to 5, characterized in that the electrode unit (20) comprises a conductor tab (28) connected to the current collector (24), which conductor tab, after being placed according to step d), protrudes beyond the first separator foil (12) and if necessary at least partially lies on the adhesive applied according to step b).

7. Method according to one of claims 1 to 6, characterized in that after the second separator foil (14) is placed according to step g), the adhesive is allowed to continue to harden in a subsequent step h).

8. Method according to one of claims 1 to 7, characterized in that the adhesive is at least partially hardened by means of UV radiation according to step c) and/or f) and/or further hardening is effected by means of UV radiation according to step h).

9. An electrode arrangement (10) manufactured according to the method of one of claims 1 to 8.

10. A battery cell comprising at least one electrode arrangement (10) manufactured according to the method of one of claims 1 to 8.