Method for producing a prismatic battery cell

Abstract

The invention relates to a method for producing a prismatic battery cell (2), wherein an electrode stack (16) is provided with first electrodes (6) and second electrodes which are stacked one over the other. Arresters (10) of the first electrodes (6) protrude beyond an end face of the electrode assembly (16), and arresters (10) of the first electrodes (6) are compacted, wherein the compacted arresters (10) are welded to a contact plate (30), and the contact plate (30) is welded to a contact element (26) of a cell cover (50). The invention additionally relates to such a prismatic battery cell (2).

Description

[0001] Description

[0002] Method for producing a prismatic battery cell

[0003] The invention relates to a method for producing a prismatic battery cell, in which conductors of the first electrodes are compacted and welded to a contact plate. Furthermore, the invention relates to a prismatic battery cell produced according to the method.

[0004] An electrically powered motor vehicle typically has a traction battery (high-voltage battery, HV battery) that supplies energy to an electric motor to drive the motor vehicle. An electrically powered motor vehicle is understood to mean, in particular, an electric vehicle that stores the energy required for propulsion solely in the traction battery (BEV, battery electric vehicle), an electric vehicle with a range extender (REEV, range extended electric vehicle), a hybrid vehicle (HEV, hybrid electric vehicle), a plug-in hybrid vehicle (PHEV, plug-in hybrid electric vehicle), and / or a fuel cell vehicle (FCEV, fuel cell electric vehicle), which temporarily stores the electrical energy generated by a fuel cell in the traction battery.

[0005] Such a traction battery typically comprises several battery cells, in particular lithium-ion battery cells, which are electrically connected to one another in series and / or in parallel.

[0006] Battery cells are classified into different types depending on their design. For example, a pouch cell (coffee bag cell) has a foil, in particular an aluminum composite foil, as a casing in which the battery cell's electrodes are enclosed. A cylindrical battery cell, in contrast, comprises a comparatively rigid housing, in particular made of sheet metal, with the housing essentially having a circular-cylindrical shape. Also known are so-called prismatic battery cells, whose housings are also comparatively rigid, in particular made of sheet metal, and are essentially cuboid-shaped.

[0007] A battery cell is known from US 2012 / 0171568 A1. It comprises a plurality of electrode films, a terminal welded to the plurality of electrodes, and a buffer film welded to the plurality of electrodes, with the plurality of electrodes arranged between the terminal and the buffer film.

[0008] US 11,158,914 B2 discloses a battery with an electrode body and an internal terminal. The electrode body includes positive and negative electrode blades. The internal terminal includes a connector connected to protruding portions of the electrode blades. The protruding portions are bent around a base end.

[0009] US Pat. No. 9,935,305 B2 describes a secondary battery whose battery device is encased in an outer material. The battery device comprises a positive and a negative electrode, with a positive tab electrically connected to the positive electrode and extending to the outside of the outer material. A negative tab is electrically connected to the negative electrode and extending to the outside of the outer material.

[0010] The invention is based on the object of providing a particularly suitable method for producing a prismatic battery cell. Furthermore, such a battery cell and an electrically powered motor vehicle comprising such a battery cell are to be provided.

[0011] With regard to the method, the object is achieved according to the invention by the features of claim 1. With regard to the battery cell, the object is achieved according to the invention by the features of claim 9, and with regard to the motor vehicle by the features of claim 10. Advantageous embodiments and further developments are the subject of the dependent claims. The statements made in connection with the method also apply mutatis mutandis to the battery cell, and vice versa.

[0012] The method serves to produce a prismatic battery cell. This is expediently designed as a lithium-ion battery cell. Preferably, the battery cell is intended and configured for a traction battery of an electrically powered motor vehicle.

[0013] First, an electrode stack is provided which has first electrodes and second electrodes stacked one above the other in a direction referred to here and below as the stacking direction or the stack vertical direction. The electrode stack is therefore formed from a number of first electrodes and a number of second electrodes, wherein the electrodes are arranged one above the other in the stacking direction. The first and second electrodes are expediently arranged alternately, with a separator being arranged between a first electrode and the second electrode adjacent to it. Each of the first electrodes is designed, for example, as a cathode and each of the second electrodes as an anode.

[0014] Each electrode is suitably sheet-like. The respective electrode is formed from a foil-like substrate, in particular from a metal foil. The respective substrate comprises a (first) section coated with an active material and a second section, in particular molded onto this section. The second section is also referred to as a flag. The coated section of the substrate of each of the electrodes expediently has a rectangular, in particular non-square, base area. In the electrode stack, the first sections of the electrodes each span a surface perpendicular to the stacking direction.

[0015] The conductor preferably extends upwards from the shorter side of the rectangular first section of the respective substrate. It is advisable for the conductor not to extend over the entire side.

[0016] Suitably, in the electrode stack, the conductors of the first electrodes extend away from the first section of the respective substrate in a direction referred to as the longitudinal direction, which is perpendicular to the stacking direction, and the conductors of the second electrodes extend away from the first section of the respective substrate opposite to the longitudinal direction. Thus, the conductors of the first electrodes are arranged one above the other in the stacking direction, and the conductors of the second electrodes are arranged one above the other in the stacking direction. The conductors of the first electrodes are arranged on the side of the electrode stack referred to as the first end face, and the conductors of the second electrodes are arranged on the second end face of the electrode stack opposite the first end face, i.e. oriented parallel to the first end face and perpendicular to the stacking direction.

[0017] In summary, the arresters of the first electrodes are arranged on the first end face of the electrode stack and the arresters of the second electrodes are arranged on the second end face opposite the first end face.

[0018] According to the process, the arresters of the first electrodes are compacted. The arresters are pressed and / or crimped together in the stacking direction. A clamping tool, for example, is used for this purpose. Alternatively or additionally, an ultrasonic tool is used for compaction. For example, in addition to compaction, the arresters are pre-fixed to one another by ultrasonically welding them together in sections or at specific points.

[0019] The compacted conductors of the first electrodes are then trimmed, i.e., cut to size, specifically, by cutting them off. A portion of the compacted section is removed so that the free ends of the conductors are aligned in the stacking direction.

[0020] The compacted (and possibly trimmed) arresters of the first electrodes are then welded to an electrically conductive contact plate. Specifically, the arresters are ultrasonically welded to the contact plate. For this purpose, the compacted area of ​​the arresters is placed between the contact plate and a sacrificial plate, so that the ultrasonic welding tools only touch the contact plate or sacrificial plate.

[0021] The contact plate and / or the sacrificial plate are made of aluminum or copper, for example.

[0022] The contact plate is then welded, in particular laser-welded, to a contact element of a cell cover of a cell housing. The contact plate is preferably arranged directly on the contact plate. The contact element is expediently arranged on the side of the contact plate facing away from the conductors and, if applicable, the sacrificial plate. The contact element particularly preferably forms a terminal of the battery cell. In other words, the contact element can be electrically and / or mechanically contacted from the outside of the battery cell. In still other words, the contact element extends through the cell cover. The contact plate is therefore welded to the inside of the contact element.

[0023] In summary, the contact element is electrically connected to the arresters via the contact plate.

[0024] In particular, the contact element is designed as a single piece, i.e., monolithic. Furthermore, the cell cover is conveniently designed as a single assembly, meaning it is pre-assembled. This eliminates the need to install or assemble the cover after welding.

[0025] The cell cover is then particularly preferably arranged on the first end face of the electrode stack. Thus, in the assembled state, the cell cover covers the end face in the longitudinal direction. For this purpose, the conductors of the first electrodes, particularly in their non-compacted area, are bent such that the cell cover covers the end face of the electrode stack after bending. Thus, the conductors of the first electrodes are bent such that the cell cover, particularly its outer side, is oriented parallel to the first end face. The bending (folding over) is expediently carried out using at least one blade. In summary, the inner side of the contact element, i.e. the side of the contact element to which the contact plate is welded, is adjusted towards the first end face due to the bending.

[0026] Due to the rigidity of the contact plate and / or the sacrificial plate, and thus the rigidity of the arresters in the section joined to them, it is advantageously possible to fold the arresters using only one (single) blade. For this purpose, the blade, which extends transversely, is advantageously moved against the arresters in a direction opposite to the stacking direction, i.e., onto the top side of the arresters in their non-welded section.

[0027] According to an advantageous embodiment, to form the electrode stack (before its provision, thus before the conductors of the first electrodes are welded), two separate individual stacks are stacked one on top of the other. Each of the individual stacks comprises first electrodes and second electrodes stacked one on top of the other. The first and second electrodes are fixed to one another, for example, using an adhesive tape (fixing tape). For example, each of the individual stacks comprises between 50 and 200, in particular 100, first electrodes and between 50 and 200, in particular 100, second electrodes.

[0028] The two individual stacks are then stacked on top of each other to form the electrode stack, with the conductors of the first and second electrodes positioned one above the other in the stacking direction. The conductors of the first electrodes are then compacted, preferably cut to size, and welded together.

[0029] Advantageously, a deviation in the positioning of the electrodes relative to one another is smaller when the electrode stack is formed from individual stacks than when a (single) electrode stack is formed with a correspondingly larger number of electrodes.

[0030] As an alternative to forming the electrode stack by stacking the two individual stacks on top of each other, it can be produced using what is known as butterfly welding. Here, the individual stacks are first arranged next to one another in such a way that their end faces with the arresters of the first electrodes lie opposite one another, i.e. face one another, with the individual stacks being inclined towards one another. In particular, the arresters of the two individual stacks are arranged in such a way that the uppermost arrester of the first individual stack, i.e. the arrester facing the second individual stack, is arranged on the uppermost arrester of the second individual stack, i.e. the arrester facing the first individual stack. The arresters of the first electrodes are then welded together, expediently ultrasonically welded. Subsequently, one of the individual stacks is folded onto the other individual stack to form the electrode stack.In this variant, the compaction of the arresters before welding to the contact plate can and is expediently omitted.

[0031] According to an advantageous embodiment, the upper and / or lower conductors with respect to the vertical stack direction are provided with, in particular glued, a protective film, in particular an electrically insulating one. In this way, damage to the conductors during assembly of the battery cell, in particular when the conductors are bent, is advantageously avoided or the risk of such damage is at least reduced. Furthermore, contact of the bent conductors with the edges of the second electrodes on the first end face is avoided.

[0032] Preferably, the respective protective film projects beyond the arresters in a transverse direction oriented transversely to the longitudinal direction and the stacking direction. In other words, the protective films project laterally beyond the arresters, i.e., along the short edge of the first sections of the substrates. For a comparatively secure hold, the protective films are also attached, in particular glued, to the top side of the electrode stack or to the bottom side of the electrode stack in sections, particularly at the ends in the longitudinal direction.

[0033] The top side refers to the upper side of the electrode stack in terms of the stacking direction, and the bottom side refers to the lower side of the electrode stack in terms of the stacking direction. The top side and bottom side are oriented perpendicular to the stacking direction.

[0034] A sweatband is used in particular as a protective film.

[0035] A stopper frame is expediently provided for the battery cell, which covers the first end face. According to an advantageous development of the method, the contact plate welded to the arresters is guided through a passage in the stopper frame, in particular a hole-like passage, i.e., a passage that is continuous in the longitudinal direction, prior to its welding to the contact plate. The stopper frame is preferably arranged on the first end face, in particular placed on the first end face, i.e., pushed onto the first end face. The contact plate and the arresters thus protrude through the passage after the stopper frame is arranged on the first end face.

[0036] The stopper frame and the electrode stack are preferably secured using a securing film. For this purpose, the electrode stack and the stopper frame are wrapped in the securing film, for example. The securing film is then preferably joined to the stopper frame, in particular by hot-staking or welding. The securing film is preferably electrically insulating.

[0037] According to an advantageous embodiment of the method, a housing shell of a cell housing is pushed over the contact plate and over the electrode stack. This method step expediently takes place before the contact plate is welded to the contact element. In this way, the electrode arrangement is accommodated in the cell cup, which delimits the cell interior. The housing shell is formed, for example, from a sheet metal, in particular from aluminum. The housing shell collectively forms the side walls of the battery cell housing, which are oriented parallel to the longitudinal direction. Together with the cell lid or with a cell base, the housing shell forms a so-called cell cup. The housing shell is therefore hollow-cylindrical, with the cylinder having a rectangle as its base.

[0038] In particular, due to the use of the contact plate, an electrical connection of the arrester to the contact element (by means of the contact plate) is possible even when the housing shell has already been pushed on and thus in a comparatively tight installation space.

[0039] According to a practical embodiment, the cell cover is arranged on the free end side of the housing shell, in particular resting against it. The free end side of the housing shell is the side oriented perpendicular to the longitudinal direction, i.e., the direction of extension of the housing shell. The cell cover therefore conceals the housing shell in the longitudinal direction; in particular, the cell cover is aligned with the housing shell in the assembled state in the longitudinal direction. For example, the stopper frame forms a stop or a support for the cell cover. In particular, the stopper frame forms a spacer element by means of which the cover is held at a distance from the electrode stack.

[0040] In summary, the cell lid closes an opening in the housing shell. If the contact plate is welded to the contact element after the contact plate and electrode stack have been passed through the housing shell, the comparatively complex process of passing the cell lid, which is larger than the opening in the cell cup, is avoided. This also reduces the risk of damage to one of the battery cell components.

[0041] To arrange the cell cover welded to the contact plate, thus closing the housing shell, the arresters are bent as described above, for example using a sword.

[0042] According to a preferred embodiment of the method, the weld seam resulting from the welding of the contact plate to the contact element is covered with an additional protective film, preferably before the cell cover is arranged by bending the arresters on the first end face. For this purpose, the additional protective film is glued, for example, to the contact plate. This at least covers the weld seam, preferably also the sacrificial plate. The additional protective film prevents damage to the arresters during the arrangement of the cell cover due to welding residues, a sharp edge, or a burr in the weld seam.

[0043] A further aspect of the invention relates to a prismatic battery cell manufactured according to the method in one of the variants described above. The battery cell thus comprises an electrode stack with first and second electrodes stacked, expediently alternating, one above the other. The conductors of the first electrodes are arranged on a (first) end face of the electrode stack. The conductors are compacted and welded, in particular ultrasonically welded, to a contact plate, with the contact plate in turn being welded, in particular laser-welded, to a contact element of a cell cover.

[0044] Preferably, the electrode stack is again formed by two individual stacks stacked on top of each other.

[0045] Preferably, the upper and / or the lower arrester with respect to the stack vertical direction is provided with a protective film, in particular an electrically insulating one.

[0046] Preferably, the conductors are guided through a passage of a stopper frame arranged on the (first) end face of the electrode stack. Preferably, the electrode stack and the stopper frame are secured to each other by means of a fixing foil.

[0047] Preferably, a housing shell of a cell housing is pushed over the contact plate and the electrode stack (and, if present, over the stopper frame). When assembled, the contact plate and the electrode stack are arranged in the interior of the housing, thus in the space enclosed by the housing shell.

[0048] Preferably, the cell cover is arranged on the (first) end face of the electrode stack. This advantageously rests against the stopper frame. The stopper frame is thus arranged between the cell cover and the end face of the electrode assembly. Particularly preferably, the cell cover is arranged on the free end side of the housing shell, thus covering it in a direction parallel to a central axis of the housing shell.

[0049] Preferably, the weld seam resulting from the welding of the contact plate to the contact element is covered, in particular taped, with a further protective film.

[0050] A further aspect of the invention relates to an electrically driven motor vehicle having a prismatic battery cell formed in one of the variants described above and / or manufactured according to the method in one of the variants described above.

[0051] In particular, the motor vehicle comprises a traction battery (HV battery) designed and configured to provide electrical energy for a traction drive. The prismatic battery cell is part of the traction battery.

[0052] In the following, exemplary embodiments of the invention are explained in more detail with reference to a drawing. In the drawings:

[0053] Fig. 1 is a flow chart representing a process sequence for producing a battery cell,

[0054] Fig. 2 shows a schematic perspective view of two individual stacks which are stacked one above the other to form an electrode stack, Fig. 3 shows a schematic perspective view of the electrode stack, with its second conductors being in contact with a cell bottom,

[0055] Fig. 4 shows a schematic and partial side view of compacted first conductors of the electrode stack, wherein the first conductors are ultrasonically welded to a contact plate,

[0056] Fig. 5 shows a schematic perspective view of the electrode stack, with a stopper frame being pushed over the contact plate,

[0057] Fig. 6 shows a schematic perspective view of the electrode stack, the stopper frame and the cell base, which are fixed by means of a fixing film,

[0058] Fig. 7 shows a schematic perspective view of a housing shell which is pushed over the stopper frame and the electrode stack,

[0059] Fig. 8 shows a schematic perspective view of the contact sheet which is laser welded to a contact element of a cell cover,

[0060] Fig.9 schematically and in perspective view the contact plate is covered with another protective film,

[0061] Fig. 10 schematically and in perspective view the battery cell, with the cell cover closing the housing shell, and

[0062] Fig. 11 a sectional view through the cell lid.

[0063] Corresponding parts and sizes are always provided with the same reference symbols in all figures.

[0064] In Fig. 1, a method for producing a prismatic battery cell 2, in particular designed as a lithium-ion battery cell, is shown using a flow diagram.

[0065] In the method, in a first step I, two separate individual stacks 4 (individual electrode stacks 4) are stacked one above the other. This is represented by an arrow in Fig. 2. Each of the individual stacks 4 comprises a plurality of first electrodes 6 and second electrodes 8, which are alternately stacked one above the other in a stacking direction S, with a separator (not shown further) arranged between each of the first and second electrodes.

[0066] The first and second electrodes 6, 8 of each individual stack 4 are sheet-like. Each comprises a foil-like substrate with a rectangular section coated with active material and with a conductor 10. For the purpose of better differentiation, the conductors of the first electrodes 6 are referred to below as first conductors 10 and the conductors of the second electrodes 8 as second conductors 12. The first and second conductors 10, 12 protrude from the shorter side of the rectangular coated section. In each of the individual stacks 4, the first conductors 10 are arranged one above the other and the second conductors 12 are arranged one above the other, with the first conductors 10 protruding in a longitudinal direction L towards the first section and the second conductors 12 protruding opposite to the longitudinal direction L towards the section of the respective substrate.

[0067] For each of the individual stacks 4, a fixing band 14 is used, by means of which the electrodes 6, 8 of the respective individual stack 4 are fixed. The fixing band 14 is glued to an upper (top) side of the respective individual stack 4 with respect to the stacking direction S and to the lower (bottom) side of the respective individual stack 4 with respect to the stacking direction S, and overlaps a side of the respective individual stack 4 oriented parallel to the stacking direction S.

[0068] In the first step I, the two individual stacks 4 are arranged on top of one another such that the conductors 10 of the first electrodes 6 of both individual stacks 4 are arranged one above the other in the stacking direction S. Accordingly, the conductors 12 of the second electrodes 8 of both individual stacks 4 are arranged one above the other in the stacking direction S.

[0069] The first arresters 10 are arranged on one side of the formed electrode stack 16, referred to as the first end face 18, by stacking the two individual stacks 4. The second arresters 12 are arranged on the second end face 20 of the electrode stack 16, which is opposite the first end face 18, i.e., oriented parallel to it and perpendicular to the stacking direction S.

[0070] The two stacked individual stacks 4 are expediently secured to each other using a fixing band 14. In summary, the stacking of the two individual stacks 4 results in the electrode stack 16, which is provided for the further production of the battery cell 2.

[0071] In a subsequent second step II, the conductors 12 of the second electrodes 8 are connected to a cell base 22 of a cell housing 24. For example, the conductors 12 of the second electrodes 8 are compacted for this purpose and then cut to size. For example, the conductors 12 are ultrasonically welded during the compacting process. Subsequently, the conductors 12 of the second electrodes 8 are welded, for example by laser welding, to a contact element (not shown in detail) of the cell base 22. The cell base 22 is expediently arranged on the second end face 20 of the electrode stack 16, in particular by bending the conductors 12 of the second electrodes 8. The cell base 22 arranged on the second end face 20 is shown, for example, in Fig. 3.

[0072] In a subsequent third step (III), the first arresters 10 are compacted, see also Fig. 3. For this purpose, an ultrasonic tool is used, in particular, whereby the first arresters 10 are compressed. For example, the first arresters 10 are pre-fixed using the ultrasonic tools 28, in particular by ultrasonic welding them together in sections or at specific points. The ultrasonic tools 28 are only schematically indicated by rectangles in Fig. 3. Subsequently, the free end of the arrester stack comprising the compacted first arresters 10 is cut to a predetermined length.

[0073] In a subsequent fourth step IV, the compacted and cut first arresters 10 are ultrasonically welded to a contact plate 30, as shown in Fig. 4. For this purpose, the compacted area of ​​the first arrester 10 is inserted between the contact plate 30 and a sacrificial plate 32. Subsequently, the ultrasonic tools 28 only touch the contact plate 30 and the sacrificial plate 32 during ultrasonic welding, thus avoiding damage to the first arrester 10.

[0074] In a subsequent fifth step V, the first conductor 10 which is upper with respect to a stacking vertical direction Z and / or the first conductor 10 which is lower with respect to the stacking vertical direction Z is provided with an electrically insulating protective film 34.

[0075] The protective film 34 projects beyond the first arresters 10 in a transverse direction Q oriented transversely to the longitudinal direction L and the stacking direction S. The protective film thus projects laterally beyond the arresters 10. For a comparatively secure hold, the protective films 34 are also attached, in particular glued, in sections, in particular at the ends with respect to the longitudinal direction, to the top side 36 of the electrode stack or to the bottom side 38 of the electrode stack. In other words, the protective film 34 extends on the top side 36 or the bottom side 38 of the electrode stack 4, respectively, over the region of the edge of the electrode stack 16 at which the respective arrester 10 is arranged.

[0076] The top side 36 is understood to be the upper side of the electrode stack 16 with respect to the stacking direction S, and the bottom side 38 is understood to be the lower side of the electrode stack 16 with respect to the stacking direction S. The top side 36 and the bottom side 38 are oriented perpendicular to the stacking direction S.

[0077] A sweatband is used in particular as the protective film 34.

[0078] The protective film 34 applied to the upper side 36 can be seen, for example, in Fig. 5.

[0079] In a subsequent sixth step VI, see also Fig. 5, the contact plate 30 welded to the first arresters 10 is guided through a passage 40 of a stopper frame 42 extending in the longitudinal direction L. In other words, the stopper frame 42 is pushed over the contact plate 30 and the arresters 10 so that the contact plate 30 and the arresters 10 protrude through the passage 40 of the stopper frame 42.

[0080] The stopper frame 42 is arranged on the first end face 18. The stopper frame 42 is pushed onto the electrode stack 4. The stopper frame 42 is arranged on the first end face 18 such that the stopper frame 42 covers the electrode stack 16 with respect to the longitudinal direction L.

[0081] The stopper frame 42, the cell base 22, and the electrode stack 16 are then secured to one another using a preferably electrically insulating securing film 44. For this purpose, the securing film is wrapped around the electrode stack and around the side surfaces 46 of the cell base 22 and the stopper frame 42 oriented parallel to the longitudinal direction L (see also Fig. 6). For example, the securing film 44 is secured using an adhesive tape 30 after the wrapping process. Furthermore, the securing film 44 is welded or hot-stitched to the cell base 22 and to the stopper frame 42 at their side surfaces 46 oriented parallel to the longitudinal direction L. In a subsequent seventh step VII, a housing shell 48 of the cell housing 24 is pushed over the contact plate 30, over the stopper frame 42, and over the electrode stack 4 (see also Fig. 7).The housing shell 48 encompasses the cell interior, thus forming the side walls of the cell housing 24 oriented parallel to the longitudinal direction L. The housing shell 48 is thus designed as a hollow prism (hollow cylinder with a rectangular base area).

[0082] The electrode stack 4 and the stopper frame 42 are arranged in the housing shell 48, i.e., are accommodated within the space encompassed by the housing shell 48.

[0083] In a subsequent eighth step VIII, the contact plate 30 is laser-welded to a contact element 26 of a cell cover 50, see also Fig. 8. The contact element 26 forms a terminal of the battery cell 2, i.e., the contact element 26 can be electrically and / or mechanically contacted from outside the battery cell 2, see Fig. 11. The welding of the contact plate 30 thus takes place on a cell inner side of the contact element 26.

[0084] In summary, the contact element 26 is electrically connected to the first arresters 10 by means of the contact plate 30.

[0085] The cell cover 50 is designed as an assembly, meaning it is pre-assembled. The cell cover only needs to be attached.

[0086] In a subsequent ninth step IX, the weld seam 52 resulting from the welding of the contact plate 30 to the contact element 26 is covered with a further protective film 54, see also Fig. 9. In particular, the entire contact plate 30 on its cell interior as well as the sacrificial plate 32 are covered with the further protective film 54. In this way, damage to the first arrester 10, in particular due to welding residues or due to the weld seam 52 itself, is avoided.

[0087] In a subsequent tenth step X, the cell cover 50 is arranged on the free end side 56 of the housing shell 48, see also Fig. 10. Consequently, the cell cover 50 rests on the free end side 56. The free end side 56 is understood to mean the side surface of the housing shell 48 oriented perpendicular to the longitudinal direction L, thus perpendicular to the direction of extension or the central axis of the housing shell 48.

[0088] The cell cover 50 is therefore arranged such that it covers the stopper frame 42 and the first end face 18 of the electrode stack 16. The cell cover 50 thus closes the opening 58 of the housing shell 48. For this purpose, the first arresters 10 are bent accordingly, in particular in their non-compacted area, in particular folded over and / or folded in. The first arresters bent in this way can be seen particularly in the sectional view according to Fig. 11 through the cell cover 50 arranged on the housing shell 48. In summary, the inside of the contact element, i.e. the cell inside of the contact element 26, to which the contact plate 30 is welded, is tilted towards the first end face 18 due to the bending.

[0089] In an analogous manner, the cell bottom 22 is arranged on the other free end side 56 of the housing shell 48.

[0090] The cell bottom 22 and the cell lid 50 are expediently welded to the housing shell 48, in particular by laser welding in a fluid-tight manner, so that a cuboid-shaped cell housing is formed.

[0091] Conveniently, the battery cell 2 is then filled with an electrolyte through a filling opening 60 arranged in the cell lid 50. The filling opening 60 is then closed, for example, with a pin, in particular made of an elastomer. The filling opening 60 and the pin received therein are then covered, for example, by a cover, in particular made of metal, and welded to the outer wall of the cell lid 50. The filling opening 60 is thus sealed.

[0092] In a manner not shown in detail, an electrically driven motor vehicle, in particular its traction battery, has the battery cell 2.

[0093] The invention is not limited to the exemplary embodiment described above. Rather, other variants of the invention can be derived from it by those skilled in the art within the scope of the claims without departing from the subject matter of the invention. In particular, all individual features described in connection with the exemplary embodiment and / or in the claims can also be combined with one another in other ways without departing from the subject matter of the invention. List of reference symbols

[0094] Battery cell

[0095] Single stack first electrode second electrode

[0096] Arrester of a first electrode

[0097] Arrester of a second electrode

[0098] Fixing tape

[0099] Electrode stack first end face second end face

[0100] cell floor

[0101] Cell housing

[0102] Contact element / T erminal

[0103] Ultrasonic tool

[0104] Contact plate

[0105] sacrificial plate

[0106] protective film

[0107] Top of the electrode stack

[0108] Bottom of the electrode stack

[0109] Implementation

[0110] Stopper frame

[0111] Fixing film

[0112] side surface

[0113] Housing shell 50 cell cover

[0114] 52 Weld seam

[0115] 54 additional protective films

[0116] 56 Free end side

[0117] 58 Opening

[0118] 60 filling opening

[0119] L longitudinal direction

[0120] Q transverse direction

[0121] S Stacking direction / Stacking direction

[0122] I Forming the electrode stack

[0123] II Attaching the conductors of the second electrodes to the cell bottom

[0124] III Compacting and cutting the first arresters

[0125] IV Welding the arresters to the contact plate

[0126] V Applying protective films

[0127] VI Attaching the stopper frame to the first end face

[0128] VII Slide on the housing shell

[0129] VIII Welding the contact plate to the contact element of the cell cover

[0130] IX Covering the weld seam

[0131] X Closing the housing shell

Claims

Patent claims 1. A method for producing a prismatic battery cell (2), wherein an electrode stack (16) with first electrodes (6) and second electrodes (8) stacked one above the other is provided, wherein conductors (10) of the first electrodes (6) protrude from an end face (18) of the electrode arrangement (16), wherein the conductors (10) of the first electrodes (6) are compacted, wherein the compacted conductors (10) are welded to a contact plate (30), and wherein the contact plate (30) is welded to a contact element (26) of a cell cover (50).

2. Method according to claim 1, characterized in that to form the electrode stack (16) two separate individual stacks (4) are stacked on top of each other, each having first electrodes (6) and second electrodes (8) stacked one above the other and fixed to each other.

3. Method according to claim 1 or 2, characterized in that the upper conductor (10) with respect to a stack vertical direction (S) and / or the lower conductor (10) with respect to the stack vertical direction (S) are provided with a protective film (34), in particular an electrically insulating one.

4. Method according to one of claims 1 to 3, characterized in that the contact plate (30) welded to the arresters (10) is guided through a passage (40) of a stopper frame (42) before it is welded to the contact plate (30), and / or wherein the stopper frame (42) is arranged on the end face (18).

5. Method according to claim 4, characterized in that that the electrode stack (16) and the stopper frame (42) are fixed to each other by means of a fixing film (44).

6. Method according to one of claims 1 to 5, characterized in that a housing shell (48) of a cell housing (24) is pushed over the contact plate (30) and over the electrode stack (4).

7. Method according to claim 6, characterized in that the cell cover (50) is arranged on the free end side (56) of the housing shell (48).

8. Method according to one of claims 1 to 7, characterized in that the weld seam (52) resulting from the welding of the contact plate (30) to the contact element (26) is covered with a further protective film (54).

9. Battery cell (2) produced by the method according to one of claims 1 to 8.

10. Motor vehicle with a battery cell (2) according to claim 9.

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