Battery cell and method for manufacturing battery cell

Abstract

A battery cell having at least a cell housing of gas-tight design and at least one stack of electrode films arranged one above the other therein; wherein the cell housing is formed of a film material, wherein the cell housing has a housing part comprising the stack and, at at least one side of the battery cell, has an edge region formed by connecting a first end region of the film material to a second end region of the film material and protruding outwardly from the housing part in a radial direction; wherein the edge region is arranged curved toward the housing part and a channel extending in a circumferential direction is formed between the housing part and the edge region; wherein the channel is filled with additional material to at least 50% in at least one cross section of the channel extending transversely to the circumferential direction. Method for producing a battery cell.

Description

Technical Field

[0001] The invention relates to a battery cell and a method for producing a battery cell. Background Art

[0002] The battery cell comprises a cell housing of gas-tight design and at least one stack of electrode films arranged one above the other therein. The cell housing is formed of a film material. The cell housing has a housing part comprising the stack and has an edge region protruding outwardly in a radial direction from the housing part at at least one side of the battery cell, which is formed by connecting a first end region of the film material to a second end region of the film material.

[0003] A battery cell is an electrical storage device which is used, for example, in a motor vehicle to store electrical energy. In particular, a motor vehicle has, for example, an electrical machine for driving the motor vehicle, wherein the electrical machine can be driven by the electrical energy stored in the battery cell. In a battery cell, electrode films, i.e. anodes and cathodes, are arranged one above the other, wherein the different electrode films are arranged separated from one another by separator films or separator materials. The electrode films are arranged in an electrolyte. For example, battery cells with liquid or solid electrolytes (solid batteries) are known.

[0004] A battery module comprises in particular a plurality of battery cells which are electrically connected in series or in parallel with one another and are arranged in a module housing. Individual battery modules can also be electrically connected in series or in parallel with one another. A battery comprises one battery module or a plurality of battery modules.

[0005] The battery cell can be implemented as a so-called soft pack battery (or pouch battery). The soft pack battery includes a composite material as a film material for the housing. The composite material is a composite material, in particular including aluminum and plastic. The unit housing can be formed by a plurality of film materials, which are arranged one on top of the other and are constructed to include a housing part of the stack and an edge area protruding outward from the housing part in a radial direction. The unit housing can also be constructed by a single film material, wherein the unit housing is formed by folding the film material. In this case, the edge area is not constructed at least on one side of the unit housing. In the edge area, the film materials stacked one on top of the other are connected to each other in an airtight manner, in particular via a sealing seam.

[0006] There may be a requirement to connect the battery cells to a cooling element or cooling surface for cooling. The cooling may not be carried out via the side of the cell housing, where the discharger (Ableiter, sometimes also called conductor) is led out of the cell housing. Usually in soft pack batteries, the longer, narrower side is connected to the cooling surface. The connection is usually only carried out via the side where the film material is folded. On the other side, there is a sealing seam and an edge area that protrudes from the housing part accordingly, which is usually fixed by bending or folding with a tape on the housing part. Due to the folded or bent edge area, the heat conduction to the cooling surface at this side is affected. In addition, higher stresses can be introduced into the sealing seam by folding, so that the airtightness of the sealing seam cannot be guaranteed if necessary.

[0007] The adhesive tape must be attached after the folding and is therefore complex to implement. In addition, different compression states can be achieved in the battery cell by means of the adhesive tape.

[0008] DE 10 2015 110 667 A1 discloses a battery assembly with a plurality of pouch-type cells, in which the cell housing is produced by folding a film material. Thus, at opposite sides of the cell housing, the corresponding edge regions are formed once by welding and once by folding. Both sides are arranged at a cooling element to dissipate heat from the battery cells. Since the sides with welding have a poorer contact with the cooling element, the pouch-type cells are arranged alternately in different orientations. As a result, the pouch-type cells can be cooled more effectively.

[0009] DE 10 2013 016 618 A1 discloses a battery cell in which a film is welded circumferentially around a stack of electrodes to form a sealing seam. Such an edge region of the cell housing is rolled in or twice wrapped in. The sealing seam rolled in or wrapped in this way can be connected to the part of the film surrounding the stack via an adhesive.

[0010] DE 10 2014 014 529 A1 discloses a cell unit in which an arrester protruding from a housing is bent and fixed to the cell unit in a materially bonded manner via an adhesive. The materially bonded fixing is performed by means of a seal or by means of an adhesive tape. Summary of the invention

[0011] The object of the present invention is to at least partially solve the problems cited with respect to the prior art. In particular, a battery cell is to be proposed which enables an alternative fixing of the edge region to a housing part of the battery cell and which in particular enables good heat dissipation to a cooling surface also via the edge region with the sealing seam. In particular, a method for producing such a battery cell is to be proposed.

[0012] The battery cell according to the invention and the method according to the invention for producing the battery cell contribute to achieving these objects. The individual features listed in the invention can be combined with one another in a technically reasonable manner and can be supplemented by explanatory facts from the description and / or details from the drawings, wherein further embodiments of the invention are presented.

[0013] A battery cell is proposed, which has at least a cell housing that is implemented in a gas-tight manner and at least one stack of electrode films arranged one above the other therein. The cell housing is formed of a film material. The cell housing has a housing part that includes the stack, and has an edge area protruding outward from the housing part in a radial direction, which is formed by connecting a first end area of ​​the film material to a second end area of ​​the film material on at least one side of the battery cell or the cell housing. The edge area is arranged in a curved manner toward the housing part, and a channel extending in a circumferential direction is constructed between the housing part and the edge area. In at least one cross section of the channel that extends transversely to the circumferential direction, the channel is filled with additional material to at least 50%, in particular at least 75%, preferably at least 90%, and particularly preferably completely filled.

[0014] In a battery cell, electrode films, i.e. anodes and cathodes, are arranged in a stacked manner, in particular one above the other, wherein the different electrode films are arranged separated from one another by separator films or separator materials. The electrode films are arranged in an electrolyte. For example, battery cells with liquid or solid electrolytes (solid batteries) are known. Battery cells are in particular lithium-ion battery cells. The electrical contacting of the battery cell is carried out in particular via a discharger, which makes conductive contact with the electrode films inside the battery cell and extends outward via the cell housing.

[0015] The battery cell is in particular a pouch cell and differs from known pouch cells in particular by the arrangement of the edge region and the arrangement or filling with additional material.

[0016] The edge region is formed in a known manner, in particular, from regions of film materials lying one above the other, such as end regions of a single film material or end regions of different film materials. The edge region forms a gastight connection of the film materials. In particular, the edge region comprises a known sealing seam.

[0017] The edge region is arranged in a curved manner toward the housing part and a channel is thus formed between the housing part and the edge region, which channel extends around the housing part in the circumferential direction. The edge region can be arranged in a curved manner to such an extent that it contacts the housing part and thus forms a closed channel in cross section. If the edge region does not contact the housing part, the channel is open to the outside in cross section, the cross-sectional area being calculated separately. In this case, the channel is limited by the imaginary shortest connection between the edge region and the housing part.

[0018] The bent edge region is in particular formed on at least one side of the battery cell or the cell housing. The edge region in particular does not extend beyond this side to another side of the cell housing (such as, for example, an adhesive strip in known battery cells). The edge region is therefore arranged only on at least one side of the cell housing.

[0019] The channel defined in this way has in cross section a cross-sectional area which is filled on average with the additional material in the stated proportions.

[0020] No lead-through for the arrester is provided along the extension of the channel.

[0021] The additional material introduced into the channel can ensure low-stress flanging or bending of the sealing seam arranged in the edge region. The additional material arranged in the channel can support the edge region at the housing part, thereby avoiding too small a radius along the extension of the edge region in the radial direction. In particular, flanging or bending of the edge region (i.e. without a radius or with a very small bending radius, for example less than 0.5 mm, measured at the surface of the edge region oriented toward the bending radius) can be prevented.

[0022] Furthermore, uniform pressing of the stack of electrode films in the battery cell can be ensured.

[0023] In particular, if the additional material is selected with regard to heat conduction, the additional material can achieve an improved heat conduction from the battery cell via the housing part to the cooling surface contacting the edge region. Thus, a connection of the edge region of the battery cell to the cooling surface can be achieved, including a connection of the film material, if necessary via a sealing seam, which can achieve a corresponding heat dissipation from the battery cell compared to a side without such an edge region.

[0024] The additional material hardens in particular automatically. Thermal hardening (at room temperature) is possible. The hardening of the additional material can be accelerated by heat treatment.

[0025] In the operationally ready state of the battery cell, the additional material is in particular fixed in position, ie it has not automatically loosened from the original arrangement in the channel. This state is referred to as dimensionally stable. The additional material can be deformed elastically or only plastically in this state.

[0026] The additional material is in particular an adhesive, by which the edge region is connected to the housing part. The edge region is fixed in its position by the adhesive, that is to say the connection between the additional material and the edge region or between the additional material and the housing part can only be undone by destroying the additional material.

[0027] The additional material is in particular a heat-conducting material. The heat conductivity of the additional material is in particular of the order of magnitude of the heat conductivity of the film material, i.e. at least 10%, in particular at least 50%, of the heat conductivity of the film material, which is applied to the unit housing. In particular, the additional material has a higher heat conductivity than the film material.

[0028] In particular, the additional material comprises at least one polymeric material (eg, epoxy, acrylic, silicone) and a filler material having a higher thermal conductivity than the polymeric material.

[0029] The filler material comprises, in particular, metal oxides or carbon. The filler material can be present as particles and / or fibers.

[0030] Furthermore, a method for producing a battery cell, in particular for producing the described battery cell, is proposed. The method comprises at least the following steps:

[0031] a) providing at least one stack of electrode films arranged one above the other;

[0032] b) providing at least one film material;

[0033] c) arranging at least one film material on the stack and forming a cell housing of gas-tight design at least by connecting a first end region of the at least one film material to a second end region of the at least one film material, so that the cell housing has a housing part comprising the stack and, on at least one side of the battery cell, has an edge region formed by connecting the first end region to the second end region and protruding outwardly from the housing part in a radial direction;

[0034] d) Arranging additional material on the unit housing and bending the edge area towards the housing part, thereby constructing a channel extending in the circumferential direction between the housing part and the edge area; wherein the channel is filled with additional material to at least 50% in at least one cross section of the channel extending transversely to the circumferential direction.

[0035] The above (non-final) division of the method steps into a) to d) should only serve to differentiate and not to impose a sequence and / or dependency. The frequency of the method steps can also vary. For example, a plurality of stacks etc. can be provided. It is also possible that the method steps overlap with each other at least partially in time. It is quite particularly preferred that the arrangement of the additional material takes place before, during or after the bending edge region. In particular, steps a) to d) are carried out in the order listed.

[0036] In particular, before or during step d), at least the edge region is heated to at least 35 degrees Celsius, in particular at least 45 degrees Celsius, preferably at least 55 degrees Celsius. In particular, heating to temperatures exceeding 80 degrees Celsius is avoided. In particular, this can accelerate the hardening of the additional material.

[0037] In particular, before step d), the regions of the cell housing, in particular housing parts and / or edge regions, which are contacted by the additional material, are surface treated in order to improve the adhesion of the additional material.

[0038] In particular, the surface treatment can include (chemical) activation and / or plasma cleaning. In particular, a mechanical surface treatment can be performed, for example by introducing a texture, i.e. a surface structuring, for example in the form of increased roughness and / or in the form of depressions and / or elevations. In particular, the surface treatment can be performed during the production of the unit housing, for example during the forming or deep drawing of a film material.

[0039] In particular, in step d), first a preforming of the edge region is performed, then the additional material is applied, and finally the final forming of the edge region is performed. In the context of the preforming, for example, first a bending of the edge region at a first angle (starting from the edge region arranged approximately orthogonally to the side surface after step c) and extending in the radial direction) is performed.

[0040] The first angle amount is, for example, at least 60 degrees, preferably at least 80 degrees, particularly preferably at least 90 degrees, relative to the extension of the edge region present after step c).

[0041] Due to the preforming, the channel is at least preformed in such a way that the application of the additional material is facilitated. In particular, the additional material is prevented from escaping from the channel due to the at least partially curved shape of the edge region. At the same time, the preformed channel remains accessible for applying the additional material, since the channel has an opening between the edge region and the side or housing part that is open to the surroundings and extends in the circumferential direction.

[0042] In particular, after the application of the additional material, the final shaping of the edge region is carried out, wherein the edge region bent by the first angular amount is now bent further toward the housing part by the second angular amount. The sum of the angular amounts is greater than the first angular amount. The first angular amount and the second angular amount together give in particular at least 90 degrees, preferably at least 110 degrees, particularly preferably at least 120 degrees. In particular, the edge region is bent within the scope of the final shaping to such an extent that it contacts the housing part again. Due to the contact with the housing part (and in particular in the at least partial hardening of the additional material carried out here), the channel can be implemented closed at least in the cross section, preferably in all cross sections along the extension of the channel in the circumferential direction.

[0043] In particular, a battery cell comprising at least one film material and at least one stack can be arranged in a device within the scope of step c). The device comprises, for example, a lower mold for receiving the film material and the stack. By combining the lower mold with the upper mold, the cell housing can be formed and the edge region can be constructed.

[0044] In particular, at least one side of the battery cell, a mold (i.e., the lower or upper, preferably the lower mold plate) can be partially swivellable so that the edge region can be preformed by the mold plate, i.e., bent at a first angle. The swivellable mold contacts the edge region so that the edge region is bent toward the other mold plate.

[0045] Then (i.e. after preforming and in particular before applying additional material), the other (preforming) tool can be replaced, in particular relative to the final forming tool, wherein the edge region is further bent toward the housing part by the device. In particular, the final forming (i.e. further bending of the edge region by a second angle) can also be carried out by the or (another) pivotable section of the template, preferably the lower template.

[0046] In particular, at least the edge region is heated (only) during preforming, (only or additionally during application of the additional material), (only or additionally) during final shaping or (only or additionally) after final shaping. In particular, the additional material is hardened while the battery cell is arranged in the device and fixed by the mold, i.e. under prestress.

[0047] Preferably, the additional material is hardened after the final shaping and while the edge region is held under prestress in the position bent at the second angle.

[0048] Furthermore, a battery cell assembly is proposed, which comprises at least the battery cell or the battery cell produced by the method and a cooling surface, wherein the battery cell is arranged on the cooling surface via an edge region or is in thermally conductive contact. In particular, the battery cell assembly comprises a plurality of battery cells.

[0049] The cooling surface is, in particular, a solid body which is acted upon or flows through by a cooling fluid (for example a liquid or a gas), preferably on the side facing away from the cooling surface.

[0050] In particular, during the operation of the battery cell, the heat from the battery cell is conducted to the surroundings via the cooling surface. Obviously, the battery cell can also be temperature-controlled via the cooling surface, that is to say, the battery cell is also heated at least temporarily, that is to say, heat is conducted from the cooling surface toward the battery cell.

[0051] In particular, the statements made regarding the battery cell also apply to the method and the battery cell assembly, and vice versa.

[0052] In particular, the battery cell assembly is used or employed in a motor vehicle, in particular for providing electrical energy for a traction drive.

[0053] In particular, in the present invention, the use of indefinite articles ("a" and "an") is to be understood as such and not as a numeral. The corresponding terms or components introduced therein are therefore to be understood as such, that they exist at least once and in particular may also exist in multiples.

[0054] It should be noted as a precaution that the numerals used here ("first", "second", ...) are primarily (only) used to distinguish between a plurality of similar objects, quantities or processes, i.e., in particular, do not necessarily define a dependency and / or sequence of these objects, quantities or processes. If a dependency and / or sequence is required, this is explicitly stated here or is obvious to a person skilled in the art when studying the specifically described design. As long as a component can appear multiple times ("at least one"), a description of one of these components can also apply to all or part of a plurality of these components, but this is not mandatory. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] The invention and the technical field are explained in more detail below with reference to the accompanying drawings. It should be noted that the invention is not limited to the embodiments listed. In particular, as long as it is not explicitly indicated otherwise, some aspects of the facts illustrated in the figures can also be extracted and combined with other components and insights from the present description. In particular, it should be noted that these figures and the dimensional relationships shown in particular are only schematic. Among them:

[0056] Figure 1 A partial area of ​​a known battery cell is shown in a perspective view;

[0057] Figure 2 A partial area of ​​a first embodiment variant of a battery cell assembly and a battery cell is shown in a side view;

[0058] Figure 3 A partial area of ​​a second embodiment variant of a battery cell is shown in a perspective view;

[0059] Figure 4 The perspective diagram shows the Figure 2 Battery cells;

[0060] Figure 5 A device for producing a battery cell during preforming of the edge region is shown in a side view in section;

[0061] Figure 6 The side view in section shows the final shaping of the edge region according to Figure 5 Devices;

[0062] Figure 7 The perspective diagram shows the Figure 6 devices; and

[0063] Figure 8The side view in section shows the process of curing the additional material according to Figure 6 and Figure 7 device. DETAILED DESCRIPTION

[0064] Figure 1 A partial area of ​​a known battery cell 1 is shown in a perspective view. The battery cell 1 comprises a cell housing 2 which is designed to be gas-tight and a stack 3 of electrode films 4 arranged one above the other arranged therein. The cell housing 2 is formed by a film material 5. The cell housing 2 has a housing part 6 which comprises the stack 3 and, on at least one side 7 of the battery cell 1, has an edge area 11 which is formed by connecting a first end area 8 of the film material 5 to a second end area 9 of the film material 5 and which protrudes outward from the housing part 6 in a radial direction 10.

[0065] The battery cell 1 is designed as a so-called pouch cell. In the edge region 11 , the film materials 5 arranged one above the other are connected to each other in a gas-tight manner via a sealing seam. On the other side 7 arranged adjacent to the side 7 having the edge region 11 , a discharger 19 extends from the cell housing 2 .

[0066] An adhesive tape 20 is provided on the side 7 with the protruding edge region 11, by which the edge region 11 is fixed to the housing part 6 by bending or flanging or folding. Starting from the side 7, the adhesive tape extends via the edge region 11 toward the adjacent side 7 of the unit housing 2.

[0067] Figure 2 A partial area of ​​a first embodiment variant of a battery cell assembly 17 and a battery cell 11 is shown in a side view. Figure 1 implementation plan.

[0068] The battery cell arrangement 17 comprises a battery cell 1 and a cooling surface 18 , wherein the battery cell 17 is arranged on the cooling surface 18 via an edge region 11 .

[0069] The cooling surface 18 is a solid body which is acted upon or flows through by a cooling fluid (for example a liquid or a gas) on the side facing away from the cooling surface 18 .

[0070] The battery cell 1 has a cell housing 2 of gas-tight design and a stack 3 of electrode films 4 arranged one above the other therein. The cell housing 2 is formed of a film material 5. The cell housing 2 has a housing part 6 comprising the stack 3 and has an edge region 11 protruding outward from the housing part 6 in a radial direction 10, formed by connecting a first end region 8 of the film material 5 with a second end region 9 of the film material 5, on a side surface 7 of the battery cell 1. The edge region is bent toward the housing part 6 and a channel 13 extending in a circumferential direction 12 is formed between the housing part 6 and the edge region 11. The channel 13 is completely filled with an additional material 15 in a cross section 14 of the channel 13 extending transversely to the circumferential direction 12.

[0071] The battery cell 1 is a pouch cell and differs from known pouch cells in the arrangement of the edge region 11 and in the arrangement of the additional material 15 .

[0072] The edge region 11 is formed by overlapping regions of the film material 5, for example end regions 8, 9 of a single film material 5 or end regions 8, 9 of different film materials 5. The edge region 11 forms a gastight connection of the film materials 5. The edge region 11 has a sealing seam for connecting the film materials 5 to one another.

[0073] The edge region 11 is arranged bent toward the housing part 6 and thus forms a channel 13 between the housing part 6 and the edge region 11, which extends around the housing part 6 in a circumferential direction 12. The edge region 11 is not bent to such an extent that it again contacts the housing part 6, so that the channel 13 is open to the outside in a cross section 14. As shown, the channel 13 is limited by the imaginary shortest connection between the edge region 11 and the housing part 6.

[0074] The channel 13 defined in this way has, in the cross section 14 , a cross-sectional area which is completely filled with the additional material 15 .

[0075] No lead-through for the arrester 19 is provided along the extension of the channel 13 .

[0076] By means of the additional material 15 introduced into the channel 13, a low-stress flanging or bending of the sealing seam arranged in the edge region 11 can be ensured. The additional material 15 arranged in the channel 13 can support the edge region 11 at the housing part 6, thereby avoiding too small a radius along the extension of the edge region 11 in the radial direction 10. Thus, flanging or bending of the edge region 11 can be prevented. That is, it is prevented that the edge region 11 has too small a bending radius 21 in its extension in the radial direction 10.

[0077] The additional material 15 allows an improved conduction of heat from the battery cell 1 via the housing part 6 to the cooling surface 18 of the contact edge region 11 .

[0078] According to step a) of the method for producing a battery cell 1, a stack 3 of electrode films 4 arranged one above the other is provided. According to step b), at least one film material 5 is provided. According to step c), at least one film material 5 is arranged on the stack 3 and a cell housing 2 of gas-tight design is formed by connecting at least a first end region 8 of the at least one film material 5 and a second end region 9 of the at least one film material 5, so that the cell housing 2 has a housing part 6 comprising the stack 3 and has an edge region 11 protruding outward from the housing part 6 in a radial direction 10 on at least one side 7 of the battery cell 1, which is formed by connecting the first end region 8 and the second end region 9. According to step d), an additional material 15 is arranged on the cell housing 2 and the edge region 11 is bent toward the housing part 6, so that a channel 13 extending in a circumferential direction 12 is formed between the housing part 6 and the edge region 11. The channel 13 is completely filled with the additional material 15 in a cross section 14 of the channel 13 extending transversely to the circumferential direction 12. Figure 2 The state of the battery cell 1 after step d) is shown. Prior to step d), the region 16 of the cell housing 2 , ie the housing part 6 and / or the edge region 11 , which is contacted by the additional material 15 , is surface treated in order to improve the adhesion of the additional material 15 .

[0079] The bent edge region 11 is formed on the side surface 7 of the battery cell 1 or the cell housing 2 and extends only up to the upper edge of this side surface 7 and does not extend beyond this side surface 7 to the other side surface 7 of the cell housing 2 (as for example in the embodiment according to Figure 1 In the case of the known battery cell 1 of FIG. 2 , the edge region 11 is arranged only on one side surface 7 of the cell housing 2 .

[0080] Figure 3 A partial area of ​​a second embodiment variant of a battery cell 1 is shown in a perspective view. Figure 2 implementation plan.

[0081] The edge region 11 is shown before and after the bending. At the other side 7 arranged adjacent to the side 7 with the edge region 11, the arrester 19 extends from the cell housing 2. The edge region 11 has an angled portion of the film material 5. The bending radius 21 generated by the bending and supported by the additional material 15 is arranged along the extension of the edge region in the radial direction 10 between the angled portion and the housing part 6.

[0082] Figure 4 The perspective diagram shows the Figure 2 of battery cell 1. Figure 2 implementation plan.

[0083] The edge region 11 is shown before and after the bending. At the other side surface 7 arranged adjacent to the side surface 7 having the edge region 11 , an arrester 19 extends out of the cell housing 2 .

[0084] Figure 5 A device 22 for producing a battery cell 1 during the preforming of the edge region 11 is shown in a side view in section. Figure 6 The side view in section shows the final shaping of the edge region 11 according to Figure 5 Device 22. Figure 7 The perspective diagram shows the Figure 6 The following describes Figures 5 to 7 . Reference for Figures 2 to 4 implementation plan.

[0085] In step d) of the method, first the edge region 11 is preformed (left side of the device 22) and then the additional material 15 is applied (see Figure 6 On the right side of the device 22), and finally the final shaping of the edge region 11 is carried out (see Figure 6 on the left side of the device 22).

[0086] In the context of preforming (see Figure 5 7 on the left side of the device 22 in the embodiment), firstly, the edge region 11 is bent by a first angle 23 (starting from the edge region 11 which is arranged approximately orthogonally to the side 7 after step c and extends in the radial direction 10, see Figure 5 On the right side of the device 22 ). The first angular amount 23 is approximately 90 degrees relative to the extension of the edge region 11 present after step c).

[0087] Due to the preforming, the channel 13 is preformed at least in such a way that the application of the additional material 15 is facilitated. The additional material 15 is prevented from escaping from the channel 13 due to the at least partially curved shape of the edge region 11. Furthermore, the escape of the additional material 15 from the end of the channel 13 is prevented by the device 22. At the same time, the preformed channel 13 remains accessible for applying the additional material 15, because the channel 13 has an opening between the edge region 11 and the side 7 or the housing part 6 which is open to the surroundings and extends in the circumferential direction 12 (see Figure 6 on the right side of the device 22).

[0088] After the application of the additional material 15, the edge region 11 is finalized (see the side 7 on the left side of the device 22), wherein the edge region 11 bent by the first angular amount 23 is now bent further toward the housing part 6 by the second angular amount 24. The first angular amount 23 and the second angular amount 24 give a total of approximately 120 degrees. In the course of finalization, the edge region 11 is bent to such an extent that it contacts the housing part 6 again. Due to the contact with the housing part 6 (and in particular during the at least partial hardening of the additional material 15 that takes place here), the channel 13 can be designed to be closed in all cross sections 14 along the extension of the channel 13 in the circumferential direction 12.

[0089] To carry out the method, within the scope of step c), the battery cell 1 including the film material 5 and the stack 3 is arranged in an apparatus 22. The apparatus 22 includes a lower mold 25 for accommodating the film material 5 and the stack 3. By combining the lower mold 25 with the upper mold 26, the cell housing 2 can be formed and the edge region 11 can be formed.

[0090] At the side 7 of the battery cell 1, the lower tool 25 is partially pivotable so that the edge region 11 can be preformed by the lower tool 25 or its pivotable section 27, i.e., the edge region 11 can be bent at a first angle 23. In this case, the pivotable section 27 contacts the edge region 11 in such a way that the edge region 11 is bent toward the upper tool 26.

[0091] Then (ie after preforming and in particular before applying the additional material 15) the upper (preforming) mold 26 (see Figure 5 ) relative to the final molding die 28 (see Figure 6 and Figure 7 ) is replaced, wherein the final shaping die 28 does not extend along the side 7 of the battery cell 1. The lower die with the swingable section 27 can now bend the edge region 11 further toward the housing part 6 by an additional second angle 24 (see Figure 6 On the left side of the device 22; see also Figure 7 ).

[0092] Figure 8 The side view in section shows the process during the curing of the additional material 15 according to Figure 6 and Figure 7 The device 22. Figures 5 to 7 implementation plan.

[0093] After preforming and before applying additional material 15 , upper (preforming) template 25 is displaced relative to final forming template 28 , wherein edge region 11 is further bent toward housing part 6 by device 22 or by pivotable section 27 of lower template 25 .

[0094] After the edge region 11 has been formed at the second angle 24, at least the edge region 11 is heated. The curing of the additional material 15 also takes place while the battery cell 1 is arranged in the arrangement 22 and fixed by the templates 25, 28, that is, under prestress. Figure 8 As shown in FIG, this prestress can be generated via a tension spring 29 which connects the pivotable section 27 .

[0095] Reference numerals list

[0096] 1 Battery Cell

[0097] 2-unit housing

[0098] 3 piles

[0099] 4 Electrode film

[0100] 5 film materials

[0101] 6 Shell part

[0102] 7 Side

[0103] 8 First end region

[0104] 9 Second end region

[0105] 10 Radial direction

[0106] 11 Marginal Area

[0107] 12 Circumferential direction

[0108] 13 channels

[0109] 14 Cross section

[0110] 15 Additional Materials

[0111] 16 Regions

[0112] 17 Battery Cell Assembly

[0113] 18 Cooling surface

[0114] 19 Discharger

[0115] 20 Tape

[0116] 21 Bending radius

[0117] 22 Installation

[0118] 23 First Angle Measurement

[0119] 24 Second Angle Measurement

[0120] 25 Lower mold

[0121] 26 Upper mold

[0122] 27 Segment

[0123] 28 Final molding die

[0124] 29 Tension spring.

Claims

1. A battery cell (1) comprising at least a cell housing (2) of gas-tight design and at least one stack (3) of electrode films (4) arranged one above the other therein; wherein: The cell housing (2) is formed of a film material (5), wherein the cell housing (2) has a housing portion (6) including the stack (3), and has an edge region (11) on at least one side (7) of the battery cell (1) formed by connecting a first end region (8) of the film material (5) with a second end region (9) of the film material (5), and protruding outward from the housing portion (6) in a radial direction (10); wherein the edge region (11) is arranged in a bent manner toward the housing portion (6) and is disposed at the housing portion (6). A channel (13) extending along a circumferential direction (12) is constructed between the body part (6) and the edge area (11); wherein the channel (13) is filled with additional material (15) to at least 50% in at least one cross section (14) of the channel (13) extending transversely to the circumferential direction (12), wherein the additional material (15) is able to support the edge area (11) at the shell part (6) so as to prevent the edge area (11) from having an excessively small bending radius (21) in its extension along the radial direction (10).

2. The battery cell (1) according to claim 1, wherein: The additional material (15) is an adhesive, by means of which the edge region (11) is connected to the housing part (6).

3. The battery cell (1) according to any one of the preceding claims 1 to 2, wherein: The additional material (15) comprises at least one polymer material and a filler material having a higher thermal conductivity than the polymer material.

4. The battery cell (1) according to claim 3, wherein: The filler material includes metal oxide or carbon.

5. A method for manufacturing a battery cell (1), comprising at least the following steps: a) providing at least one stack (3) of electrode films (4) arranged one above the other; b) providing at least one film material (5); c) arranging the at least one film material (5) at the stack (3) and constructing a cell housing (2) of gas-tight design at least by connecting a first end region (8) of the at least one film material (5) to a second end region (9) of the at least one film material (5), so that the cell housing (2) has a housing part (6) comprising the stack (3) and has an edge region (11) protruding outwardly from the housing part (6) in a radial direction (10) on at least one side surface (7) of the battery cell (1) formed by connecting the first end region (8) to the second end region (9); d) arranging an additional material (15) at the unit housing (2) and bending the edge region (11) towards the housing part (6), thereby constructing a channel (13) extending along a circumferential direction (12) between the housing part (6) and the edge region (11); wherein the channel (13) is filled with the additional material (15) to at least 50% in at least one cross section (14) of the channel (13) extending transversely to the circumferential direction (12), wherein the additional material (15) is able to support the edge region (11) at the housing part (6), thereby preventing the edge region (11) from having an excessively small bending radius (21) in its extension along the radial direction (10).

6. The method according to claim 5, wherein: Prior to or during step d), at least the edge region (11) is heated to at least 35 degrees Celsius.

7. The method according to any one of the preceding claims 5 and 6, wherein: In step d), the edge region (11) is first preformed, then the additional material (15) is applied, and finally the edge region (11) is final formed; wherein, within the scope of the preformed, the edge region (11) is bent at a first angle (23), and within the scope of the final formed, the edge region (11) is further bent at a second angle (24); wherein the sum of the angles (23, 24) is greater than the first angle (23).

8. The method according to claim 7, wherein: After final shaping and while the edge region (11) is held under prestress in a position bent at the second angle (24), the additional material (15) is allowed to harden.

9. The method according to any one of the preceding claims 5 to 6, wherein: Prior to step d), the area (16) of the cell housing (2) contacted by the additional material (15) is subjected to a surface treatment in order to improve the adhesion of the additional material (15).

10. A battery cell assembly (17) comprising at least a battery cell (1) according to any one of the preceding patent claims 1 to 4 or a battery cell (1) manufactured by a method according to any one of patent claims 5 to 9 and a cooling surface (18), wherein: The battery cell (1) is arranged via the edge region (11) on the cooling surface (18).

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