CN111095647B

CN111095647B - Electrode device, method of manufacturing the same, and battery cell including the electrode device

Info

Publication number: CN111095647B
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: 2023-10-31
Anticipated expiration: 2038-08-30
Also published as: KR102616553B1; KR20200051751A; DE102017216101A1; WO2019052819A1; CN111095647A

Abstract

A method for manufacturing an electrode arrangement is proposed. The method comprises the following steps: a first separator foil is provided. An adhesive is first applied to the first separator foil in a first coating pattern to form a first adhesive coating. The adhesive is at least partially age hardened. An electrode unit is provided and placed on the first separator foil, the electrode unit including 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. The adhesive is applied a second time in a second coating pattern to form a second adhesive coating that is at least partially over the first adhesive coating. The adhesive applied during the second application is at least partially age hardened. A second separator foil is provided and is placed on the bare side of the electrode unit, the second separator foil being connected to the first separator foil by means of an adhesive that is applied at the time of the first coating and at the time of the second coating.

Description

Electrode device, method of manufacturing the same, and battery cell including the electrode device

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 bare side of the electrode unit and the two separator foils are connected to each other 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

The electrical energy may be stored with the use of 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 charged again. And the secondary battery pack, which is also called a secondary battery, can be recharged. Hereinafter, the term battery pack is used for not only the primary battery pack but also the secondary battery pack, following common usage.

Lithium ion batteries are known in the prior art and are characterized by high energy density. The lithium ion battery basically includes a cathode, an anode, a separator disposed between the anode and the cathode, and an ion-conducting electrolyte. Here, the membrane has the following tasks: the anode and cathode are electrically isolated from each other, wherein ion conduction through the membrane is enabled.

A method for manufacturing a battery is known from US 2015/0140394 A1, wherein a frame area is defined on the surface of a conductive substrate, on which frame area an adhesive is at least partially applied, wherein an interior area enclosed by the frame area is substantially free of adhesive. A cathode material is coated onto the interior 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 adhesive-equipped region. An electrolyte material is coated onto the cathode material, which is electrically insulating but ion conductive. Next, an anode material is applied to the electrolyte material, wherein a cathode current collector is conductively connected to the anode material and protrudes beyond the substrate. Finally, the substrate is folded together with the layers arranged thereon, wherein the battery formed therein is sealed with the applied adhesive.

From KR 2004-0079033 an apparatus for continuous manufacturing of battery cells is known, in which separator material is unwound from a roll, the surface of the separator is coated with an adhesive, electrode plates are placed on the separator and a bond between the separator and the electrode plates is established by means of the action of heat.

To manufacture the diaphragm bag, two diaphragm 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 separator layers. In the known method, the ratio of the height to the width of the bond is limited such that a relatively large volume of the battery cells 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. The adhesive is then applied to the first separator foil for a first time in accordance with a predetermined first coating pattern, wherein a first adhesive coating is formed. The adhesive is then 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. The adhesive is then applied a second time in accordance with a predetermined second coating pattern, wherein a second adhesive coating is formed, which is at least partially disposed 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 bare side of the electrode unit, wherein the second separator foil is connected to the first separator foil by means of an adhesive that is applied at the time of the first coating and at the time of the second coating.

The thickness of the first adhesive coating and of the second adhesive coating, respectively, immediately after the 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 preferable that: the thickness of the first adhesive coating layer is in the range of 80% to 120% of the thickness of the first active material layer before the step after the first coating is performed. Also, it is preferable that: the thickness of the second adhesive coating layer is in the range of 80% to 120% of the thickness of the second active material layer before the step after the second coating is performed. It is particularly preferred that for the first adhesive coating and/or for the second adhesive coating, a thickness in the range of 100% to 120% of the thickness of the first or second active material layer is selected.

The first and/or second application of the material may be realized in the form of one layer or in the form of multiple layers, respectively. In this case, when a plurality of layers are applied, 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 a plurality of layers, the previously coated layers of adhesive may be at least partially age-hardened after each of these layers is applied. Also conceivable are: this intermediate age hardening is only performed when two or more layers have been applied. For example, such intermediate age hardening may be performed 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.

An outer area is defined on the first separator foil by means of the one or more continuous adhesive lines and/or by means of the individual adhesive dots, which outer area is provided for connection between the first separator foil and the second separator foil. The inner area on the first separator foil is used to put the electrode unit on and is free of adhesive. Preferably, the inner region is implemented coherently. The inner region may be embodied, for example, as a rectangle, wherein the outer region at least partially encloses the inner region.

In particular when the first separator 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 separator foil. The outer region can in particular be designed discontinuously and can be embodied in two strips, which are each adjacent to 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 adhesive lines can be applied in each case both to the first outer region and to the second outer region, wherein the adhesive lines extend in the transport direction of the material web, wherein the first outer region and the second outer region each comprise at least one continuous adhesive line. In the case of a coating pattern comprising individual adhesive dots, these adhesive dots can in particular be arranged along a straight line, wherein the 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 individual adhesive dots are applied.

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

The thickness of the adhesive is defined in this case in a direction which runs perpendicularly to the surface of the first separator foil and corresponds to the stacking direction in the production of the electrode arrangement. The width of the continuous adhesive line is defined here in the direction perpendicular to the thickness and to the direction of the line along which the adhesive coating is to be effected.

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. Here, the diameter of the adhesive dot is relative to a plane corresponding to the plane of the first separator foil. The ratio of diameter to thickness is preferably in the range from 0.5:1 to 2:1.

The pattern characterizing the adhesive coating in the form of individual adhesive dots or continuous lines of adhesive is referred to as a coating pattern.

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

Preferably, after the second separator foil has been placed, the previously coated 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 adhesive that is 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 hardening of the adhesive and further age hardening is achieved by the action of UV radiation. In this case, the UV radiation is in particular electromagnetic radiation having a wavelength in the range of approximately 200nm to 380 nm. Examples of binders which harden by UV radiation are acrylates, such as Panacol company4731-VT or AD491 from Delo corporation. Another example is a photo-cured epoxy such as KL6006 by Best corporation.

Alternatively, an adhesive that hardens by the action of heat can be used, for example. In this case it is preferred that: at least partial hardening and/or further hardening is achieved by means of 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-melt adhesives are, for example, those from Henkel companyAS4206。

In the case of a coating in the form of a continuous line of adhesive, the adhesive is preferably applied using a dispenser from which the adhesive is continuously released. In the case of a coating in the form of individual adhesive dots, it is preferable to use a coating head which can release individual adhesive drops in a targeted manner as required. Such a coating head is also called a spray dispenser or a sprayer.

The electrode unit used to manufacture the electrode device is preferably an electrode unit suitable for manufacturing a lithium ion battery. In particular, the invention relates to an electrode unit suitable as a cathode or anode of a lithium ion battery.

The electrode unit designed as an anode preferably comprises: a current collector composed of copper, for example; 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, in addition to 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 include a cathode material that can reversibly intercalate and re-transfer lithium ions. Examples of suitable active materials for the cathode are in particular metal oxides such as NCA (lithium nickel cobalt aluminate), NCM (lithium nickel cobalt manganate).

The separator foil is embodied such that it acts as an electrical insulation, but is permeable to lithium ions. Suitable materials for the separator foil include, for example, porous plastic films, for example porous plastic films 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 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 using one of the described methods. Depending on the choice of electrode unit, the electrode means is a cathode or anode for a battery cell, which is accommodated in a separator pouch. Accordingly, the electrode device can be combined into a galvanic cell by combining an electrode device comprising a cathode as electrode unit with an anode and an electrolyte and being accommodated in a housing. It is also possible that: an electrode device including an anode as an electrode unit is combined with a cathode and an electrolyte and is accommodated in a case. It is also possible to manufacture electrode stacks in which one of the described electrode arrangements, with an electrode unit enclosed between the separator foils, is stacked alternately with one other electrode each. In this case, in one embodiment variant, the electrode units arranged between the two diaphragm foils are implemented as cathodes, so that the electrode arrangements are each stacked alternately with anodes, while in another embodiment variant, anodes are each accommodated between the two diaphragm foils as electrode units, so that the electrode arrangements are stacked alternately with cathodes.

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

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

THE ADVANTAGES OF THE PRESENT INVENTION

With the proposed method, an electrode arrangement can be manufactured simply, wherein an electrode unit is enclosed between two separator foils. Here, the two membrane foils are bonded to each other, so that a membrane pouch is formed. In order to achieve an optimal separator pouch, the adhesive used to connect the two separator foils should be applied such that the thickness of the adhesive essentially corresponds to the thickness of the electrode unit accommodated between the two separator 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 coatings of adhesive drops, correspondingly applicable are: the adhesive drop has a diameter at least as large as its thickness. Thus, in order to achieve the desired thickness of the adhesive coating, relatively much space of the battery cell is occupied by the adhesive. Because the adhesive does not positively contribute to energy storage, the power density of the battery cells is reduced thereby.

And in the proposed method 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 and second applications and is at least partially located on the first adhesive coating when the adhesive is applied to the second application. Thus, according to the invention, provision is made for: at least two adhesive layers are applied in total by at least a first application and a second application, wherein preferably the same coating pattern is used separately and the at least two adhesive layers are at least partially stacked together. In a preferred ideal case, the respective individual layers of adhesive overlap without misalignment. Because the first adhesive coating has at least partially age hardened prior to the second coating, the first adhesive coating does not break apart and the first adhesive coating is dimensionally stable. If one adhesive layer is now applied in each case in the first adhesive coating and in the second adhesive coating, a total of two adhesive layers are applied, and in this way a total thickness of the adhesive can be achieved which is considerably greater than the width of the continuous adhesive line or the diameter of the adhesive dots. For example, in the case of a total of two layers, a thickness to width ratio or 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 during the first application and/or during the second application. In this way, the thickness-to-width ratio or thickness-to-diameter ratio can be further improved, so that an adhesive coating of large thickness is achieved with a relatively small width or diameter. 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 achievable thickness to width ratio of the adhesive lines or the achievable thickness to diameter ratio of the adhesive dots is for example in the range of 0.5:1 to 10:1.

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

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

In addition, the provision of adhesive joints in the form of continuous adhesive lines may reduce 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 device additional stability.

Drawings

Embodiments of the invention are illustrated in the accompanying drawings and 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 representation of a first variant of the embodiment 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 an electrode arrangement;

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

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

Detailed Description

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

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

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

To perform the first adhesive coating 16, two first applicators 30 are provided, by means of which the continuous adhesive line 48 is applied in each of the first outer region 52 and in the second outer region 56. Behind these first drip emitters 30, seen in the transport direction 40, the first light sources 32 are arranged in each case not only for the first outer region 52 but also for the second outer region 56. UV light is emitted by the first light source 32, which UV light is suitable for partially age hardening the coated adhesive. The respective adhesive lines 48 are partially age hardened by means of the first light source 32 such that the adhesive lines are stable. In this case, shape stabilization is understood to be: the continuous adhesive line 48 applied by the first dispenser 30 does not break apart, 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 attached to the 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, the electrode unit 20 is placed onto the inner region 54 of the first separator foil 12, seen in the transport direction 40. 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, which is electrically connected to the current collector 24 of the electrode unit 20. The conductor webs 28 project beyond the first membrane foil 12 and are thus located on the adhesive lines 48 or the first adhesive coating 16 that are applied by means of the first dispenser 30.

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

After the electrode unit 20 is discharged, the adhesive is applied a second time by means of the second dispenser 31, as seen along the transport means 40. This second coating is again performed so that continuous lines of adhesive 48 are released, wherein these continuous lines of adhesive form the second adhesive coating 18. The second adhesive coating 18 is implemented according to the same pattern as for the first adhesive coating 16 such 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 released by the first dispenser 30.

After the second application of the adhesive, the adhesive is then partially age-hardened, as seen in the transport direction 40, wherein for this purpose the second light source 33 is provided in each case for both the first outer region 52 and the second outer region 56. The second light source 33 also emits UV light which is suitable for partially age hardening the coated adhesive.

After the second light source 33 has been partially age hardened, the continuous adhesive line 48 applied by the second dispenser 31 is also dimensionally stable, but can be connected to the underlying continuous adhesive line 48 and to the subsequently applied second separator foil 14.

After partial age hardening by means of the second light source 33, the second separator foil 14 is provided and, as seen in the transport direction 40, is placed onto the electrode unit 20 and onto the adhesive coating 16, 18 at the first outer region 52 and at the second outer region 56 using the deflection roller 38. Here, a connection is intermediately established between the first and second separator foils 12, 14 by means of the first and second adhesive coating 16, 18.

Preferably, the second separator foil 14 is also provided in the form of an endless material, which may for example be present in the form of a roll on a drum and be unwound for processing.

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

Optionally, the second separator foil 14 may be placed next to it, allowing the applied adhesive to fully age harden. For this purpose, as seen in the transport direction 40, third light sources 34 can be arranged in each case both for the first outer region 52 and for the second outer region 56, which third light sources emit UV light which is set up for the complete age hardening of the adhesive.

In other embodiments in which instead of an adhesive age-hardened by means of UV light, an adhesive age-hardened by means of heat generation is used, heat sources may be arranged separately from the light sources 32, 33, 34. Such a heat source may be designed, for example, as an IR radiator.

Fig. 2 shows a schematic top view of the method for producing the first embodiment variant schematically shown in fig. 1. As 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 in 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 between the first outer region 52 and the second outer region 56 is free of adhesive. The electrode unit 20 is located entirely in the inner region 54 on the first separator foil 12, except for its conductor tab 28.

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

As can be seen from the illustration in fig. 3: an electrode unit 20 including a first active material layer 22, a current collector 24, and a second active material layer 26 is positioned on the first separator foil 12, wherein the first active material layer 22 of the electrode unit 20 is directly connected with 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 can be seen in the first visible outer region 52, which has a thickness d and a width b. 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 existing immediately after the coating is performed. In particular in the case of adhesive coatings having a thickness greater than the thickness of the active material layer, the adhesive is deformed by other adhesive coatings and/or by placing 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 sectional view in fig. 3.

On the side of the conductor tab 28 facing away from the first adhesive coating 16, a second adhesive coating 18 is placed, 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 likewise covered with the second adhesive coating 18 in the stacking direction of the electrode arrangement 10, so that the bonding 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 an electrode arrangement 10 according to the invention. In the second embodiment of fig. 4, the first adhesive coating 16 and the second adhesive coating 18 are implemented in the form of a first layer 42 and a second layer 43, respectively, with respect to the first embodiment of the electrode device 10 described with reference to fig. 3. By means of a multilayer application of the adhesive, the first adhesive coating 16 or the second adhesive coating 18 has a total thickness D, which consists of the thickness D of the individual layers 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. Here, the regulations concerning the thickness of the respective layers 42, 43, the total thickness D of the first adhesive coating 16 or the second adhesive coating 18, and the width b relate to the state after the second separator foil 14 has been placed, respectively.

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

In contrast to the first embodiment variant of the method described with reference to fig. 1, the first and second application of adhesive is not carried out using the dispenser 30, 31, but rather by means of the applicator heads 44, 46. The first adhesive coating 16 is applied to the first membrane foil 12 by the first application head 44 both in the first outer area 52 and in the second outer area 56, wherein the adhesive is released in a pattern comprising adhesive dots 50 arranged along a straight line. The first application is followed by a first partial age hardening, seen in the transport direction 40, wherein the first light source 32 is used again for this purpose. After partial age hardening, the electrode unit 20 is placed onto the first separator foil 12, wherein the first active material layer 22 is again located entirely in the inner region 54 and is 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 has been placed, a second application of the adhesive takes place, which is carried out by means of the second application head 46. The same coating pattern is also used for the second coating such that the adhesive dots 50 of the second adhesive coating 18 are applied congruently with and thus are located on the adhesive dots 50 of the first adhesive coating 16. The adhesive is then partially age-hardened a second time, for which purpose the second light source 33 is again used. Next to this is a second separator foil 14, wherein the second separator foil 14 is pressed again by means of the deflection roller 38 onto 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 then cured completely using the third light source 34.

Fig. 6 shows a second embodiment variant of the production method in a schematic view from above. This view can be seen well: the 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 entirely in the inner region 54 on the first separator foil 12, except for its conductor webs 28.

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

Claims

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

a. providing a first membrane foil (12);

b. applying an adhesive to the first separator foil (12) for a first time in accordance with a predetermined first coating pattern, wherein a first adhesive coating (16) is formed;

c. partially age-hardening the adhesive coated in step b);

d. providing an electrode unit (20) and placing the electrode unit on the first separator foil (12), wherein the electrode unit (20) comprises a first active material layer (22), a current collector (24) and a second active material layer (26) in this order, 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 predetermined second coating pattern, wherein a second adhesive coating (18) is formed, which is at least partially located on the first adhesive coating (16);

f. partially age hardening the adhesive coated in step e); and also

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

wherein the coating pattern comprises one or more continuous lines of adhesive (48), and/or wherein the coating pattern comprises individual adhesive dots (50),

wherein the first adhesive coating (16) and the second adhesive coating (18) are formed such that the total thickness of the adhesive is greater than the width of the adhesive line or the diameter of the adhesive dot.

2. The method according to claim 1, characterized in that the thickness of the first adhesive coating (16) is in the range of 80% to 120% of the thickness of the first active material layer (22) before the step after step b) is performed; 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 performed.

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

4. Method according to claim 1 or 2, characterized in that the electrode unit (20) comprises a conductor tab (28) connected to the current collector (24), which conductor tab protrudes beyond the first separator foil (12) after being placed according to step d) and is optionally at least partially located on the adhesive applied according to step b).

5. Method according to claim 1 or 2, characterized in that after the second separator foil (14) has been placed according to step g), the adhesive is allowed to continue to harden in the next step h).

6. Method according to claim 1 or 2, characterized in that the adhesive is partially hardened by means of UV radiation according to steps c) and/or f) and/or further hardening is achieved by means of UV radiation according to step h).

7. An electrode arrangement (10) manufactured according to the method of one of claims 1 to 6.

8. Battery cell comprising at least one electrode arrangement (10) manufactured according to the method of one of claims 1 to 6.