DE102019216043A1 - Process for the production of an energy cell as well as an energy cell - Google Patents

Abstract

A method for producing an energy cell (2) is specified, several separator layers (8) and several electrode layers (10) being placed on top of one another in a stacking direction (S) so that a stack (4) is formed, with the separator layers (8) an adhesive (12) is applied, by means of which the separator layers (8) are connected to one another so that the separator layers (8) are fixed, the entire stack (4) subsequently being surrounded by a cell envelope (6) so that the separator layers (8 ) and the electrode layers (10) are fixed by the cell envelope (6). An energy cell (2) is also specified.

Description

The invention relates to a method for producing an energy cell and an energy cell.

Energy cells are also referred to as battery cells or accumulator cells and are used as a mobile energy source. An energy cell can in principle be used individually. Typically, however, several often identical energy cells are combined to form a battery module. The voltage and current of the battery module can then be set by appropriately interconnecting the energy cells. Energy cells and also battery modules are used, for example, in an electric or hybrid vehicle to supply an electric drive train of the vehicle with energy. An example of an energy cell is a lithium-ion cell.

A single energy cell is composed of at least two different electrodes, namely an anode and a cathode, between which a separator is arranged. Frequently, several such elements consisting of anode, separator and cathode are arranged next to one another and separated by additional separators. An electrolyte is arranged between the electrodes. The separator prevents direct contact of the electrodes with one another and is usually porous, thereby allowing charges to move from one electrode to the other. In the production of an energy cell, the electrodes and the separators are suitably combined and provided with a common cover, namely a cell cover, which protects the electrodes and separators from the environment and vice versa. Only two poles for contacting the energy cell are led out of the cell envelope.

Energy cells and processes for their production are described, for example, in US Pat DE 10 2014 215 948 A1 and the U.S. 4,802,275 A . There a rolled energy cell is described in each case, in which several layers are rolled up to form a roll. Finally, one end of the roll is glued to a previous winding of the roll.

Against this background, it is an object of the invention to provide an improved method for producing an energy cell and an improved energy cell. The handling of the electrodes and separators during assembly during the production of the energy cell should be as simple as possible and influence the finished energy cell as little as possible.

The object is achieved according to the invention by a method with the features according to claim 1 and by an energy cell with the features according to claim 10. Advantageous configurations, developments and variants are the subject matter of the subclaims. The statements in connection with the method also apply mutatis mutandis to the energy cell and vice versa.

The method is used to manufacture an energy cell and is therefore a manufacturing method. In the method, a plurality of separator layers and a plurality of electrode layers are laid one on top of the other in a stacking direction, i.e., stacked, so that a stack is formed. The electrode layers and the separator layers are also generally referred to as “layers”. In the stack, the electrode layers and the separator layers are alternately placed on top of one another, i.e. viewed in the stacking direction, a separator layer is followed by an electrode layer and vice versa. The electrode layers are in particular formed alternately as a cathode layer and as an anode layer. Overall, there are at least two electrode layers in the stack, namely at least one anode and at least one cathode, which are then separated from one another by a separator layer. An electrode layer which is an anode consists for example of graphite, silicon or titanium oxides, an electrode layer which is a cathode consists for example of lithium nickel / cobalt / manganese oxides or lithium iron phosphates. The specific choice of material is immaterial in the present case. A respective electrode layer is expediently connected to a current collector, which preferably consists of a metal, e.g. copper for the anode and aluminum for the cathode.

An adhesive is applied to the separator layers, by means of which the separator layers are connected to one another, so that the separator layers are fixed. In particular, the adhesive is applied directly and immediately to a respective separator layer. In particular, however, the adhesive is not applied to the electrode layers and thus only connects the separator layers to one another, but not the separator layers to the electrode layers. The adhesive is advantageously used to fix the separator layers during the production of the energy cell, before the entire stack is surrounded by the cell envelope. This prevents the layers from slipping in the loose state, so to speak, without a cell envelope. The adhesive thus represents a kind of auxiliary material in production and is basically no longer required in the finished energy cell, since the cell envelope then takes over the fixation.

Subsequently, ie after the stack has been completely formed and after the adhesive has been applied, the entire stack is included surrounded by a cell envelope, so that the separator layers and the electrode layers are fixed by the cell envelope. In particular, the cell envelope lies against the stack. The stack is tightly enclosed by the cell envelope and thereby fixed, so that the electrode layers and the separator layers are firmly positioned relative to one another. The adhesive remains on the separator layers and is thus arranged as part of the stack within the cell envelope. As a result of the method, the stack is preferably completely enclosed by the cell cover, in particular only two poles for contacting the electrode layers are led to the outside through the cell cover.

Since the layers are placed on top of one another in a stacking direction and are not rolled, in the present case no roll is formed, but a stack. Each layer preferably extends as a flat, straight plane. In particular, all layers are aligned parallel to one another. The stack is in particular open to the side, that is to say perpendicular to the stacking direction, so that the electrode layers between the separator layers are basically accessible, at least during manufacture. When viewed perpendicular to the stacking direction, a corresponding layer structure can then also be seen. In the finished energy cell, on the other hand, the entire stack is enclosed by the cell envelope and the layer structure and the open sides of the stack are correspondingly covered.

An embodiment is particularly preferred in which the separator layers are designed as layers that are separate from one another, so that the stack is a so-called single sheet stack. The assembly of the layers to form a stack is then also referred to as “single-sheet-stacking”, since each layer is a separate sheet. The electrode layers are also each preferably in the form of a separate sheet. In principle, however, an alternative with a so-called Z-fold is also conceivable and suitable, in which a separator is guided in a Z-shape alternately over several in particular separate electrode layers and thereby forms several separator layers which are, however, connected to one another, namely by one or more corresponding folds at the side of the stack. In this respect, a certain amount of fixation has already been achieved. In this case too, however, the application of an adhesive for further fixing is advantageous, in particular in order to glue those folds of the separator to one another which are arranged on the same side of the stack and are adjacent in the stacking direction.

The invention is initially based on the observation that an additional fixation of at least the separator layers in the stack is advantageous in order to subsequently safely surround the stack with a cell envelope and thereby prevent the layers from slipping relative to one another. In principle, it is possible to use an adhesive tape for this purpose, which is adhered to or around the stack after the stack has been formed, in order to fix the separator layers. The problem here, however, is that such an adhesive tape has a certain thickness and is correspondingly thick, which leads to an inhomogeneous surface of the stack with attached adhesive tape. This in turn leads to an uneven pressure load after the stack is wrapped with the cell envelope. For example, the adhesive tape is composed of a carrier and the actual adhesive, which is applied to the carrier, so that the overall thickness is in the range from 20 μm to 60 μm. Since the adhesive tape protrudes from the rest of the stack, the cell envelope presses more strongly on the stack in these areas. This uneven pressure load specifically affects the charge carrier mobility and typically leads to premature degradation in the affected areas. When charging and discharging the energy cell, these areas age faster than the other areas. In contrast, the adhesive in the present case forms a particularly thin adhesive layer, which is typically only a few micrometers or a few 10 micrometers thick and in any case is below the thickness of an adhesive tape, since there is effectively no carrier for the adhesive. An adhesive may be less convenient to use than an adhesive tape, but this is accepted in order to obtain the advantageously more homogeneous pressure load in the finished energy cell.

In addition, when using an adhesive, it is advantageously possible to fasten the separator layers to one another laterally, whereas an adhesive tape has to be guided around the stack in the manner of a clamp. When using an adhesive tape, this also runs accordingly over an upper side and an underside of the stack, so that a pressure load arises here in the finished energy cell through the cell envelope. In the present case, therefore, the adhesive is preferably applied to the side of the stack on the separator layers and precisely not on an upper side and a lower side of the stack, so that these remain free of an adhesive and each form a correspondingly homogeneous surface, which is particularly homogeneously loaded with pressure by the cell envelope .

The adhesive is preferably applied to a respective separator layer before the next separator layer is applied. Accordingly, a separator layer is alternately applied and adhesive is applied to it, and this is carried out repeatedly. The electrode layers are either separate from the Separator layers and placed alternately with them, or a respective electrode layer is already connected in advance to a separator layer and is then placed together with it. A combination of the two aforementioned variants is also possible. Two variants are also possible and suitable for the sequence in which the separator layer is applied and the adhesive is applied. In a variant, a respective separator layer is applied first, ie integrated into the stack, and only then is the adhesive applied to this separator layer. Alternatively or additionally, the adhesive is first applied to a respective separator layer and this is prepared, so to speak, and only then applied.

A respective separator layer is suitably placed on top of it and, in the process, pressed together with the subsequent, i.e. the underlying, separator layer in the area in which the adhesive is applied. With this compression, the applied adhesive is advantageously distributed across the width, i.e. between the separator layers. Two or more separator layers are pressed together in this way in the stacking direction, so that the separator layers are connected by the adhesive. The adhesive is applied in particular in an adhesive area which is in each case a partial area of a surface of a respective separator layer, so that the separator layers are accordingly connected in the adhesive area.

In a preferred embodiment, the separator layers protrude beyond the electrode layers and thereby form an electrode-free edge area in which the adhesive is or is applied. The separator layers are accordingly wider than the electrode layers, measured perpendicular to the stacking direction, so that the former protrude laterally from the stack. The edge area thus formed preferably has a width in the range from 0.5 mm to 2 mm. The adhesive is now preferably applied exclusively in this edge area or is applied there so that there is no connection to the electrode layers. Also, viewed in the stacking direction, the electrode layers as a whole are not covered by adhesive; rather, all of the adhesive is arranged to the side of the electrode layers and not above or below the electrode layers.

A respective separator layer has, in particular, several, preferably four, outer corners. In an advantageous embodiment, the adhesive is applied in the outer corners. Accordingly, the separator layers are also glued to one another at their outer corners, i.e. generally connected. The outer corners are in particular part of the edge area. The outer corners and in particular the entire edge area are particularly susceptible to deformations due to mechanical stress, e.g. kinking when handling the stack. The risk of such a deformation is significantly reduced by the described gluing at the outer corners. In a suitable embodiment, the separator layers are only glued in the outer corners, and the adhesive is accordingly applied exclusively in the outer corners.

A respective separator layer is suitably placed and held in a holding area in which the adhesive is also applied. The holding area is therefore used to handle the separator layer when the stack is assembled. The separator layer is held in the holding area, in particular by means of a holding tool, and is brought up to the stack and integrated into it. In this holding area, pressure is preferably also exerted, by means of which the separator layer is pressed together with the subsequent separator layer. Since the adhesive is now also applied here, the separator layers are specifically pressed together in the adhesive area and thus connected particularly effectively.

In an advantageous embodiment, a respective separator layer is applied by means of a tool, in particular a holding tool, which also applies the adhesive to the separator layer. The adhesive is applied during, before or after application. In particular, it is essential that the same tool fulfills two functions, namely, on the one hand, handling the separator layer, namely the application, and on the other hand, applying the adhesive. This significantly simplifies the production of the energy cell.

In a suitable embodiment, the adhesive is liquid and is applied, for example, by means of a nozzle from which the adhesive is sprayed onto a respective separator layer in an adhesive area. Alternatively or additionally, the adhesive is pasty and is sprayed on or painted on. As an alternative or in addition, the adhesive is a solid and is simply placed or put on, e.g. in the form of a preformed adhesive pad. Regardless of how the adhesive is actually discharged and applied, a corresponding discharge device is preferably mounted on the holding tool for this purpose, via which the adhesive is then applied in the holding area as described above. However, the use of a separate adhesive tool and application outside the holding area are also possible and suitable.

The adhesive is preferably applied with a layer thickness in the range from 5 μm to 20 μm. A layer thickness im is particularly preferred Range from 10 µm to 15 µm. This means that the adhesive does not apply very much and material is saved at the same time. Since a respective electrode layer between two separator layers is typically significantly thicker than the adhesive layer between these two separator layers, the separator layers are in particular deformed during connection, for example bent over, in particular in the adhesive area, so that the difference in thickness is overcome. An electrode layer has, for example, a layer thickness in the range from 100 μm to 200 μm and is thus at least one order of magnitude thicker than the adhesive layer. A respective separator layer has a layer thickness of 20 μm, for example.

The adhesive is applied, for example, in dots, circles or strips. A respective adhesive area, which is determined by the extent of the adhesive at one point, has a width, measured perpendicular to the stacking direction, which is preferably in the range from 5 μm to 500 μm, especially in the case of adhesive applied in dots or circles. If the adhesive is applied in the form of a strip, the result is a strip with a width preferably as mentioned above and a length preferably in the range from 0.5 mm to 5 mm. Other dimensions for the adhesive area are conceivable and in principle also suitable.

The adhesive and the separator layers are expediently designed in such a way that the adhesive is at least partially drawn into the separator layers. This results in a particularly firm connection of the separator layers by means of the adhesive. In particular, a respective separator layer is designed to be porous for this purpose. In an advantageous embodiment, the adhesive layer then has a layer thickness of at most 1 μm. Often the separator layers are porous anyway in order to accommodate the electrolyte and allow charge carriers to move between the electrodes. In the present case, the adhesive is now advantageously matched to the already porous separator layers in such a way that the adhesive is at least partially drawn into the separator layers.

An energy cell according to the invention has a stack and a cell cover, the stack being composed of a plurality of separator layers and a plurality of electrode layers which are stacked in a stacking direction, the cell cover surrounding the stack so that the separator layers and the electrode layers are fixed by the cell cover, wherein the separator layers are connected with an adhesive and are thereby advantageously additionally fixed. The adhesive is preferably only arranged on the side of the stack and connects the separator layers there in an edge region. In a suitable embodiment, the energy cell is a so-called pouch cell or a prismatic cell.

The energy cell is preferably produced by means of a method as described above.

• 1 eine Energiezelle in einer Schnittansicht,
• 2 die Energiezelle aus 1 in einer Draufsicht,
• 3 einen ersten Schritt bei der Herstellung der Energiezelle,
• 4 ein andere Ansicht der 3,
• 5 einen zweiten Schritt bei der Herstellung der Energiezelle,
• 6 einen dritten Schritt bei der Herstellung der Energiezelle,
• 7 einen vierten Schritt bei der Herstellung der Energiezelle,
• 8 einen fünften Schritt bei der Herstellung der Energiezelle.

Exemplary embodiments of the invention are explained in more detail below with reference to a drawing. They each show schematically:

• 1 an energy cell in a sectional view,
• 2 the energy cell off 1 in a plan view,
• 3 a first step in the manufacture of the energy cell,
• 4th another view of the 3 ,
• 5 a second step in the production of the energy cell,
• 6th a third step in the manufacture of the energy cell,
• 7th a fourth step in the manufacture of the energy cell,
• 8th a fifth step in the manufacture of the power cell.

In 1 is an energy cell 2 in a sectional view along a stacking direction S. shown. The energy cell 2 is a so-called pouch cell in the embodiment shown. In an alternative not shown is the energy cell 2 a prismatic cell. In 2 is the energy cell 2 in a plan view in the stacking direction S. shown. The energy cell 2 assigns a stack 4th on and a cell envelope 6th . The stack 4th consists of several layers of separator 8th and multiple electrode layers 10 composed which in the stacking direction S. are stacked. The electrode layers 10 and the separator layers 8th are also commonly referred to as "layers". The cell envelope 6th surrounds the pile 4th so that the separator layers 8th and the electrode layers 10 through the cell envelope 6th are fixed. The separator layers 8th are also with an adhesive 12th connected and thereby additionally fixed. The adhesive 12th is only on the side of the stack here 4th arranged and connects the separator layers there 8th in an edge area 14th .

The energy cell 2 in 1 is for example by means of a method as in 3 to 8th shown manufactured. They show 3 and 5 to 8th one step at a time in the manufacture of the energy cell 2 in a sectional view as in 1 . 4th illustrates the positioning of the adhesive 12th by taking a view of the situation 3 in a plan view as in 2 is shown. The 3 to 8th represent successive steps.

The method is generally used to manufacture an energy cell 2 . The process uses multiple layers of separator 8th and multiple electrode layers 10 in the stacking direction S. placed on top of one another, ie stacked, so that a stack 4th is formed. In the pile 4th are the electrode layers 10 and the separator layers 8th alternately laid on top of each other. The application of a separator layer 8th is in the 5 and 6th shown. The application of an electrode layer 10 is in 8th shown. The electrode layers 10 are in the present case alternately designed as a cathode layer and an anode layer. There are at least two electrode layers in total 10 in the stack 4th present, namely at least one anode and at least one cathode, which then through a separator layer 8th are separated from each other.

On the separator layers 8th becomes an adhesive 12th applied, by means of which the separator layers 8th are connected together so that the separator layers 8th be fixed. For the embodiment shown is the application of the adhesive 12th on one of the separator layers 8th explicitly in 7th shown. The adhesive 12th is in the present case directly and immediately on a respective separator layer 8th applied, but not on the electrode layers 10 so the glue 12th only the separator layers 8th connects with each other. The adhesive 12th serves to fix the separator layers 8th during the manufacture of the energy cell 2 before the entire stack 4th with the cell envelope 6th is surrounded. This will cause the layers to slip 8th , 10 in a loose state, so to speak, without a cell envelope 6th prevented. The adhesive 12th thus represents a kind of auxiliary material in production and is used in the finished energy cell 2 Basically no longer needed, because then the fixation of the cell envelope 6th is taken over.

After the stack 4th has been finished and after the adhesive has been formed 12th has been applied, the entire stack becomes 4th with a cell envelope 6th surrounded so that the separator layers and the electrode layers through the cell envelope 6th be fixed. The end result of this is in 1 shown. The cell envelope 6th is on the pile 4th which corresponds to the cell envelope 6th is tightly enclosed and thereby fixed. It can clearly be seen that the adhesive 12th on the separator layers 8th remains and thus part of the stack 4th is. How 2 made clear is the stack 4th from the cell envelope 6th completely enclosed, only two poles 16 for contacting the electrode layers 10 are through the cell envelope 6th outwards.

Because the layers 8th , 10 in the stacking direction S. are placed on top of one another and are not rolled, in the present case, accordingly, no roll is formed, but a stack 4th . As can be seen from the figures, each layer extends in the exemplary embodiment shown 8th , 10 as a flat, straight plane and all layers 8th , 10 are aligned parallel to each other. The stack 4th is open to the side, i.e. perpendicular to the stacking direction S. considered so that the electrode layers 10 between the separator layers 8th are in principle accessible, at least during manufacture, as in the 3 to 8th is shown. The layer structure can also be seen here. With the finished energy cell 2 is the entire stack 4th on the other hand from the cell envelope 6th enclosed and the layer structure as well as the open sides of the stack 4th are covered accordingly.

In the exemplary embodiment shown here, the separator layers are 8th formed as separate layers from one another, so that the stack 4th is a so-called single sheet stack. Putting the layers together 8th , 10 to the stack 4th is then also referred to as "single-sheet-stacking", as each layer is here 8th , 10 is present as a separate sheet, in this case also the electrode layers 10 . In an alternative, not shown, with a so-called Z-fold, a separator is Z-shaped alternately over several electrode layers 10 out and thereby several separator layers 8th forms, which are, however, connected to one another, namely by one or more corresponding folds on the side of the stack 4th . In this case too, an adhesive is used 12th specially applied to glue the folds of the separator to one another.

In principle, it is possible to fix the separator layers 8th to use an adhesive tape which after the formation of the stack 4th is glued to or around it. However, such an adhesive tape is dispensed with in the present case. Instead, the glue is used 12th used. This forms a particularly thin adhesive layer, which is typically only a few micrometers or a few 10 micrometers thick and in any case is below the thickness of an adhesive tape, since it is effective on a carrier for the adhesive 12th is waived.

In addition, when using an adhesive 12th the separator layers 8th attached to each other at the sides, whereas an adhesive tape clasps around the stack 4th must be led around and then accordingly also over an upper side and a lower side of the stack 4th would run. The adhesive 12th is only on the side of the stack 4th on the separator layers 8th applied and just not on a top and a bottom of the stack 4th so that they remain free of the adhesive 12th and each form a correspondingly homogeneous surface, which is covered by the cell envelope 6th is then particularly homogeneously loaded with pressure.

In the present case, the adhesive is used 12th on a respective separator layer 8th applied before the next separator layer 8th is launched. Accordingly, a separator layer is alternating 8th laid on and glue 12th applied to these and carried out repeatedly. This can first be seen in 3 , which is a separator layer 8th with applied adhesive 12th shows and an electrode layer 10 , which on the separator layer 8th and between the glue 12th is hung up. In the 5 and 6th becomes another separator layer 8th placed on the electrode layer 10. Then as in 7th shown on this further separator layer 8th another glue 12th applied. This is followed by another electrode layer 10 hung up, as in 8th is recognizable. Then the process is repeated.

In the exemplary embodiment shown, the electrode layers are 10 separate from the separator layers 8th and hung up alternately with these. In a variant that is not shown, however, a respective electrode layer is alternatively or additionally 10 already in advance with a separator layer 8th and is placed together with this as a semi-finished product, so to speak.

A respective separator layer is also used in the exemplary embodiment shown 8th first applied and only then is the adhesive 12th on this separator layer 8th applied. In a variant that is not shown, however, the adhesive is used first as an alternative or in addition 12th on a respective separator layer 8th applied and these prepared, so to speak, and only then placed and placed in the pile 4th integrated.

How out 6th can be seen, in the present case a respective separator layer is used 8th placed and thereby with the subsequent, ie the underlying, separator layer 8th in the area in which the adhesive 12th is applied, compressed. With this compression, the applied adhesive is distributed 12th advantageous in width, ie between the separator layers 8th . Two or more separator layers 8th are in this way in the stacking direction S. pressed together so that the separator layers 8th through the glue 12th get connected.

As can also be seen from the figures, the separator layers are present here 8th over the electrode layers 10 over and thereby form the edge area 14th which one is electrode-free and in which one the adhesive 12th is or is applied. The separator layers 8th are therefore perpendicular to the stacking direction S. measured wider than the electrode layers 10 so that the former is on the side of the stack 4th protrude. This is also particularly evident in the top view in 4th recognizable. The adhesive 12th is only in this edge area in the exemplary embodiment shown 14th applied or is applied there so that no connection with the electrode layers 10 he follows. Also are the electrode layers 10 in the stacking direction S. does not consider glue as a whole 12th covered, rather all glue 12th side of the electrode layers 10 arranged and not above or below the electrode layers 10 .

A respective separator layer 8th has several and here especially four outside corners 18th on where the glue is 12th is applied. The separator layers are accordingly 8th at their outer corners 18th glued together. The outside corners 18th are part of the border area 14th . In the present case, the separator layers are 8th even only in the outer corners 18th glued, the glue 12th is therefore only in the outer corners 18th applied.

In the exemplary embodiment shown, a respective separator layer is used 8th when hanging up in a holding area 20th recorded in which also the adhesive 12th is applied. The holding area 20th serves to handle the separator layer 8th when assembling the stack 4th . As from the 5 to 7th can be seen, the separator layer 8th in the present case by means of a tool 22nd , especially a holding tool, held and brought to the 4 stack and integrated into it. With the tool 22nd will be in the hold area 20th also exerted a pressure by which the separator layer 8th with the subsequent separator layer 8th is squeezed. This is in 6th shown. Since in the holding area 20 also the adhesive 12th is applied, the separator layers 8th also specifically pressed together in the adhesive area.

In the present case, the tool carries 22nd also the glue 12th on the separator layer 8th on, either during, before or after hanging up. This is in 7th shown. Same tool 22nd thus fulfills two functions, namely the application of the separator layer on the one hand 8th and also applying the glue 12th .

The adhesive 12th is liquid in one embodiment and is, for example, by means of a nozzle in the tool 22nd applied from which the adhesive 12th on a respective separator layer 8th is sprayed on in an adhesive area. As an alternative or in addition, there is the adhesive 12th pasty and is sprayed on or painted on. As an alternative or in addition, there is the adhesive 12th a solid and is simply placed or put on, for example in the form of a preformed adhesive pad.

In the present case, the adhesive is used 12th with a layer thickness d1 in the range from 5 µm to 20 µm applied. A respective electrode layer 10 between two separator layers 8th is typically significantly thicker than the adhesive layer between these two separator layers 8th , such as from 1 can be seen, so that the separator layers 8th deformed when joining. Out 6th it can be seen that in the exemplary embodiment shown, the separator layers 8th be bent in the adhesive area so that the difference in thickness is overcome. An electrode layer 10 has a layer thickness, for example d2 in the range from 100 µm to 200 µm and is thus at least one order of magnitude thicker than the adhesive layer. A respective separator layer 8th has a layer thickness, for example d3 of 20 µm.

In the embodiment shown, the adhesive 12th and the separator layers 8th designed such that the adhesive 12th at least partially in the separator layers 8th moves in. For this purpose there is a respective separator layer 8th porous. The drawing in of the glue 12th into the separator layer 8th however, it is not imperative that the adhesive is sufficient 12th Sufficient static friction is generated around the stack 4th for covering with the cell envelope 6th to fix.

List of reference symbols

2

Energy cell

4th

stack

6th

Cell envelope

8th

Separator layer

10

Electrode layer

12th

adhesive

14th

Edge area

16

pole

18th

Outside corner

20th

Holding area

22nd

Tool

d1

Layer thickness of the adhesive

d2

Layer thickness of the electrode layer

d3

Layer thickness of the separator layer

S.

Stacking direction

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 102014215948 A1 [0004]
• US 4802275 A [0004]

Claims (10)

Method for producing an energy cell (2), wherein a plurality of separator layers (8) and a plurality of electrode layers (10) are placed on top of one another in a stacking direction (S) so that a stack (4) is formed, with an adhesive (12) being applied to the separator layers (8) ) is applied, by means of which the separator layers (8) are connected to one another so that the separator layers (8) are fixed, the entire stack (4) subsequently being surrounded by a cell envelope (6) so that the separator layers (8) and the electrode layers (10) are fixed by the cell envelope (6). Procedure according to Claim 1 , wherein the adhesive (12) is applied to a respective separator layer (8) before the next separator layer (8) is applied. Method according to one of the Claims 1 or 2 , whereby a respective separator layer (8) is applied and in the process is pressed together with the subsequent separator layer (8) in the area in which the adhesive (12) is applied. Method according to one of the Claims 1 to 3 wherein the separator layers (8) protrude beyond the electrode layers (10) and thereby form an electrode-free edge region (14) in which the adhesive (12) is or is applied. Method according to one of the Claims 1 to 4th , wherein a respective separator layer (8) has several outer corners (18) and the adhesive (12) is applied in the outer corners (18). Method according to one of the Claims 1 to 5 , wherein a respective separator layer (8) is applied and is held in a holding area (20) in which the adhesive (12) is also applied. Method according to one of the Claims 1 to 6th wherein a respective separator layer (8) is applied by means of a tool (22) which also applies the adhesive (12) to the separator layer (8). Method according to one of the Claims 1 to 7th , the adhesive (12) being applied with a layer thickness (d1) in the range from 5 µm to 20 µm. Method according to one of the Claims 1 to 8th wherein the adhesive (12) and the separator layers (8) are designed in such a way that the adhesive (12) is at least partially drawn into the separator layers (8). Energy cell (2) which has a stack (4) and a cell envelope (6), the stack (4) being composed of several separator layers (8) and several electrode layers (10) which are stacked in a stacking direction (S), wherein the cell envelope (6) surrounds the stack (4) so that the separator layers (8) and the electrode layers (10) are fixed by the cell envelope (6), the separator layers (8) being connected with an adhesive (12).

Images