Battery arrangement and method for replacing a first battery cell in a cell assembly with a second battery cell

Abstract

The invention relates to a method for replacing at least one first battery cell (12') in a cell assembly (14) of a battery arrangement (10) comprising several battery cells (12, 12') and several housing units (16) which enclose respective receiving spaces (24, 24") in the first direction (x), and which each comprise an intermediate wall (18) located between two adjacent receiving spaces (24, 24"), wherein the battery arrangement (10) comprises a clamping device (28) for clamping the cell assembly (14) in the first direction (x), which is released such that a connection between the two housing units (16) adjacent to a first receiving space (24") is released and the first receiving space (24") is opened, and the cell assembly (14) is divided into at least two subassemblies (14a, 14b) which each remain clamped during the opening of the first receiving space (24").In addition, the first battery cell (12') is removed from the opened first receiving chamber (24") and at least one second battery cell (12") is inserted.

Description

[0001] The invention relates to a method for replacing at least one first battery cell in a cell assembly with at least one second battery cell. The cell assembly can be provided as part of a battery arrangement, which additionally comprises a clamping device by means of which the cell assembly is clamped. Furthermore, the invention also relates to a battery arrangement.

[0002] DE 10 2010 041 709 A1 describes a method for bracing a lithium-ion battery comprising a battery cell stack with a top surface, an opposite base surface, and a shell surface with four side surfaces, and at least two battery cells. The battery cell stack is bracing using at least one tension band, which is arranged and tensioned in the area of ​​the shell surface.

[0003] Such bracing of a cell stack is intended to counteract or limit cell swelling. Cell swelling refers to the expansion of battery cells over the course of their service life or during charging. Applying a defined counterforce to the bulging cell sides due to cell swelling improves the service life of the battery cells.

[0004] Today's battery systems or battery modules are designed in such a way that repairing individual cells or small cell packs is impossible. The next smallest unit that can be replaced is a cell module, which, depending on the battery's design, can contain up to 24 individual cells. If one cell fails, these 24 or even more cells must be replaced, making repairs extremely expensive.

[0005] CN 212380492 U describes a battery structure with replaceable battery cells.

[0006] However, this battery structure requires a lot of space.

[0007] The object of the present invention is therefore to provide a method and a battery arrangement which allow the simplest possible replacement of individual or a few cells in a cell assembly and at the same time enable the battery arrangement comprising the cell stack to be designed in the most space-saving way possible.

[0008] This object is achieved by a method and a battery arrangement having the features according to the respective independent patent claims. Advantageous embodiments of the invention are the subject of the dependent patent claims, the description, and the figures.

[0009] In a method according to the invention for replacing at least one first battery cell in a cell assembly with at least one second battery cell, the cell assembly is provided as part of a battery arrangement which, as part of the cell assembly, comprises a plurality of prismatic battery cells, at least one of which represents the at least one first battery cell.In addition, the battery arrangement has, as part of the cell assembly, a plurality of housing units which are arranged next to one another in a first direction, wherein two housing units arranged adjacent to one another in the first direction each enclose a receiving space in which at least one of the plurality of battery cells is arranged, wherein each housing unit comprises an intermediate wall, wherein one of the intermediate walls is located between two receiving spaces adjacent to one another in the first direction, and wherein the receiving spaces comprise a first receiving space in which at least the at least first battery cell is arranged. In addition, the battery arrangement comprises a clamping device by means of which the cell assembly is clamped in the first direction.Furthermore, the clamping device is released in such a way that a connection between the two housing units adjacent to the first receiving space in the first direction is released, the first receiving space is opened, and the cell assembly is divided into at least two subassemblies, each of which remains clamped in the first direction while the first receiving space is opened. Furthermore, at least the first battery cell is removed from the opened first receiving space, and at least the at least one second battery cell is inserted into the opened first receiving space.

[0010] The invention is based on several findings: Firstly, in order to be able to replace individual cells, it is advantageous if a system or module, such as the present battery arrangement, is opened in such a way that the prestress applied to the cells by means of the tensioning device is only released for the cells to be replaced. The remaining cells that are not to be replaced should not lose this prestress or should only lose it to a limited extent, as this would otherwise have a negative impact on the safety and service life of these cells. Cutting or loosening, for example, the straps by which all the cells of a conventional cell assembly are tensioned together in order to replace a single cell would therefore also damage all the other cells in such a conventional system, which would lead to premature failure of all the cells in such a conventional stack or module.This would mean that the entire module would have to be replaced in a very short time. The invention now advantageously makes it possible to release the tension only for the at least one first battery cell that is being replaced with the at least one second battery cell, while the tension of the remaining battery cells is maintained by dividing the cell assembly into at least two subassemblies. Thus, the at least one battery cell can be easily removed from the now opened first receiving space, and a corresponding second battery cell can be inserted into it. The cell assembly can then be reassembled from the subassemblies and tensioned.Furthermore, the invention is based on the finding that the cell assembly can be divided into subassemblies in a particularly simple manner if the housing for the battery arrangement comprises a plurality of individual housing units, between which the respective receiving spaces are enclosed and which accordingly have respective intermediate walls that separate the receiving spaces from one another in the first direction, i.e. are located between these receiving spaces. Such a wall can then advantageously function as a pressure plate when the cell assembly is divided into at least two subassemblies. In particular, by means of the two intermediate walls that delimit the first receiving space on both sides with respect to the first direction, pressure can be exerted on the two subassemblies temporarily created when the first receiving space is opened.These partition walls only need to withstand temporary tension during the replacement of at least one first battery cell, so they can still be designed with relatively thin walls and save space. This enables the replacement of a single battery cell or a few battery cells in a cell assembly in a particularly space-saving manner without compromising the service life of the battery cells that are not being replaced or are not being replaced.

[0011] As explained in more detail later, each receiving space can contain only a single battery cell or multiple battery cells. If multiple battery cells are arranged in each receiving space, then preferably the same number of battery cells is arranged in each receiving space. If the first receiving space, in which the first battery cell is arranged, is opened, then if additional battery cells are arranged in the first receiving space, these additional battery cells can also be replaced. This number of battery cells located in the first receiving space is then preferably replaced with a correspondingly equal number of second battery cells.

[0012] The two housing units adjacent to the first receiving space with respect to the first direction represent the two housing units adjacent to the first receiving space in and opposite to the first direction.

[0013] The first battery cell and the second battery cell are preferably at least geometrically identical or similar. Furthermore, the battery cells can be lithium-ion cells, for example. Furthermore, the battery cells are prismatic battery cells. These typically comprise six cell sides that lie opposite one another in pairs. The battery cells are preferably arranged in the battery arrangement such that their respective largest sides in terms of area are aligned substantially perpendicular to the first direction and / or face the respective adjacent partition walls, in particular up to possibly edge cells that delimit the cell assembly and counter to the first direction. These can, for example, comprise a largest side in terms of area that faces, for example, a pressure plate, which can also be referred to as an end plate, as part of the clamping device.

[0014] The tension applied to the cell assembly by the clamping device and acting in the first direction thus significantly affects the largest surface areas of the battery cells. This allows cell swelling to be most effectively limited.

[0015] The partition wall can be plate-shaped or flat. The partition wall can also have a multi-layer structure. For example, cooling channels for guiding a cooling fluid can also be integrated into the partition wall. This allows the partition wall to simultaneously function as an inter-cell cooling unit, which cools the largest surface areas of the battery cells during operation of the battery arrangement. Furthermore, it is preferred that the battery cell arranged in a receiving space contacts the partition wall or walls adjacent to the receiving space with at least one or both of its largest surface areas, in particular that it bears flatly against the partition wall or walls.

[0016] If multiple battery cells located in different receiving spaces are to be replaced, this is preferably done sequentially rather than simultaneously. Nevertheless, a simultaneous replacement would also be possible, in which case the cell assembly would then be divided into three or more subassemblies, for example, whose tension in the first direction is maintained during the replacement. However, with a sequential replacement, this simplifies the process and / or the device for maintaining the tension of the respective subassemblies.

[0017] The first receiving space is closed when the two housing parts adjacent to the first receiving space are fixed to each other. This fixation can be released, for example, by releasing the clamping device. An additional fixation can also be provided between the respective housing units, as explained in more detail later. This additional fixation can then also be released to open the first receiving space.

[0018] The two subassemblies remain permanently clamped in the first direction during the exchange of the first battery cell with the second battery cell, whereby the clamping force does not necessarily have to remain constant. However, it is preferable that the clamping force does not vary significantly during this time. Thus, the cells not located in the first receiving space never enter a completely relaxed state during the exchange process.

[0019] The battery arrangement can, for example, provide a battery for a motor vehicle, for example a traction battery.

[0020] In particular, the battery arrangement could be a high-voltage battery for a motor vehicle. Applications for stationary energy storage systems are also conceivable.

[0021] In a further advantageous embodiment of the invention, each of the housing units has a first outer wall and a second outer wall which delimit the receiving space in a second direction, wherein the intermediate wall connects the first and second outer walls to one another, in particular wherein the intermediate wall forms a U-profile or a double-T-profile with the outer walls. This profile is obtained in particular in a section perpendicular to a third direction, as defined in more detail later. A second direction can, for example, be defined in the direction from the second outer wall to the first outer wall. The first direction is generally perpendicular to the second direction and the third direction perpendicular to the first and second directions. The intermediate wall is therefore oriented substantially perpendicular to the first direction and extends from the second outer wall to the first outer wall in the second direction.The first outer wall, the second outer wall, and the intermediate wall all extend elongated in the third direction. By forming a U-profile or double-T profile, several cuboid-shaped accommodation spaces can be easily created by arranging several housing units next to each other in the first direction.

[0022] Each such receiving space, in particular again with the exception of the end-side receiving spaces of the cell assembly, is thus delimited both in and against the first direction and in and against the second direction by two housing units and their wall components.

[0023] These outer walls can also be designed with integrated cooling channels, for example. This further increases the cooling effect of the battery cells.

[0024] Furthermore, the outer walls of adjacent housing units 16 can overlap in the z-direction, in particular with a continuous or only partial overlap in the y-direction. The overlapping of the adjacent outer walls of two adjacent housing units can also provide a fluid-tight housing cover layer and a fluid-tight base. The overlapping areas can also include locking elements, by means of which the individual housing units can be locked together and thus connected to one another in a form-fitting manner.

[0025] In a further very advantageous embodiment of the invention, locking elements are arranged on a respective first and / or second outer wall, by means of which locking elements the housing units arranged adjacent to one another in the first direction are coupled to one another, in particular connected in a form-fitting manner. The individual housing units with the battery cells accommodated in the receiving spaces can thus be easily clipped together. This advantageously enables non-destructive, reversible disassembly of the housing units from one another. This in turn makes it possible to open the receiving space to be opened, in this case the first receiving space, in a simple and non-destructive manner, at least without destroying the housing units. In principle, however, other connection techniques would also be possible, if provided at all, such as gluing, welding or the like.

[0026] The clamping device can comprise the locking elements. In particular, the clamping device can also be implemented solely by the locking elements. This allows the housing units to be secured to one another and, accordingly, a clamping force can also be exerted in the first direction on the battery cells accommodated in the respective receiving spaces.

[0027] However, it is preferred that the clamping device is not implemented solely by such locking elements, but comprises another or at least one additional clamping element. This has the advantage that the housing units and their locking elements can be designed with significantly less complexity and stability, since they then do not have to absorb such high tensile forces.

[0028] Accordingly, a further advantageous embodiment of the invention is provided if the clamping device comprises a clamping band and / or a tie rod. The clamping band can, for example, run completely or only partially around the cell stack. The clamping device can, for example, also include pressure plates arranged at the ends of the cell assembly with respect to the first direction. The pressure plates can be fixed and tensioned to one another by means of clamping bands or tie rods. The fixing by means of tie rods can be effected in such a way that these tie rods fix and tension the two pressure plates to one another, for which purpose preferably at least two or four tie rods are used. Instead of the tie rods, at least one clamping band can be used in the same way. It is also possible to use several clamping bands, by means of which the pressure plates are fixed and tensioned to one another.A single, circumferential tensioning band or a continuous fiber band wrapped multiple times around the cell assembly and the pressure plates can also be used, such as a continuous fiber band made of fiber-reinforced plastic or similar. The tensioning band can also be designed as a metal band.

[0029] These clamping devices can absorb particularly large clamping forces.

[0030] In a further advantageous embodiment of the invention, an auxiliary tensioning device is arranged on the cell assembly before the tensioning device is released, by means of which the sub-assemblies are tensioned in the first direction. By means of such an auxiliary tensioning device, the tensioning of the sub-assemblies can be maintained in a particularly simple manner. This auxiliary tensioning device can, for example, be arranged on the cell assembly before the tensioning device is released and takes over the tensioning of the sub-assemblies at the latest when the tensioning device is released. The auxiliary tensioning device can therefore be arranged on the cell assembly and subsequently the tensioning device can be released and, in particular, completely or partially removed from the cell assembly, while the tensioning of the sub-assemblies is maintained by the auxiliary tensioning device.After replacement and when the clamping device or a new clamping device has been re-attached to the cell assembly, the auxiliary clamping device can be removed again.

[0031] In an advantageous embodiment of the invention, a coupling geometry is arranged on an outer side of a respective first and second outer wall facing away from the receiving space, which coupling geometry can be coupled to the auxiliary clamping device. The auxiliary clamping device, in particular comprising at least two clamping clamps, is coupled to the coupling geometries of the housing units adjacent to the first receiving space for clamping the subassemblies. The auxiliary clamping device then serves to maintain the tension of the subassemblies when the clamping device is released or has been released.

[0032] Such coupling geometries can be provided, for example, by pins and corresponding openings or locking lugs and corresponding recesses or similar. A corresponding coupling geometry is then provided accordingly by the auxiliary clamping device, for example by the aforementioned clamps. Thus, for example, clamping clamps can simply be placed around the sub-assemblies and coupled, e.g., hooked, into the corresponding coupling geometries of the housing units adjacent to the first receiving space with the free clamp ends. This allows the sub-assemblies to be clamped easily and efficiently, or their clamping can be maintained during replacement. The outer walls of the respective housing units can therefore also be used at the same time to provide such advantageous coupling geometries in order to attach the described auxiliary clamping device to them.

[0033] In a further advantageous embodiment of the invention, a plurality of battery cells are arranged next to one another in a row in a third direction in each receiving space, in particular wherein each of the battery cells has two first cell sides opposite one another in the first direction, which represent the cell sides with the largest area of ​​the six cell sides of the prismatic battery cell, and two second cell sides opposite one another with respect to the third direction, on each of which a cell pole is arranged. The battery cells can therefore advantageously be arranged in a row in the receiving space with their cell poles facing one another. This results in very flat cell rows. In particular, it is preferred that only one cell row comprising one or more battery cells is arranged in a receiving space. Therefore, several battery cells should not be arranged next to one another in the first direction within the same receiving space.This is particularly advantageous because, in order to replace a battery cell, each individual cell row can be exposed individually by opening the corresponding receiving space.

[0034] This series arrangement of battery cells also enables particularly simple and efficient cell contact, as their cell poles face each other. The interconnection or contacting of the battery cells or their cell poles can be achieved, for example, by directly contacting the cell poles with each other or via cell connectors.

[0035] In a further advantageous embodiment of the invention, after the first receiving space is opened, the plurality of battery cells located in the first receiving space are removed from the first receiving space, and a plurality of second battery cells are inserted into the first receiving space. Therefore, in the case where a plurality of battery cells are accommodated in a respective receiving space, it is preferred that, when the first battery cell is replaced, all of the battery cells located in the first receiving space are also replaced with corresponding second battery cells. This has the advantage of preventing battery cells from remaining in the cell assembly that have already been completely relaxed, which would impair their service life.

[0036] In principle, any number of battery cells can be arranged in a cell row, but preferably a single-digit number of battery cells. Thus, two, three, four, five, etc., battery cells can be arranged next to each other in a cell row.

[0037] In a further advantageous embodiment of the invention, after inserting the at least one second battery cell, the two subassemblies are arranged next to one another in such a way that the first receiving space is closed, and the clamping device or a second clamping device for clamping the cell assembly is arranged thereon. Then, for example, the auxiliary clamping device can also be removed again. If the clamping device is completely or partially destroyed during removal, for example, if a clamping band as part of the clamping device is cut, the clamping device or the destroyed part thereof can be replaced with a correspondingly new clamping device or a correspondingly new part thereof.The new, second clamping device can therefore comprise one or more clamping elements that were also part of the original clamping device, as well as, alternatively or additionally, one or more new clamping elements that were not part of the original clamping device. If the clamping device is a reusable clamping device, for example, two pressure plates that can be reversibly clamped via tie rods, the same clamping device can also be used to clamp the cell assembly with the now at least one replaced battery cell.

[0038] Furthermore, the invention also relates to a battery arrangement with a cell assembly comprising a plurality of prismatic battery cells.The cell assembly has a plurality of housing units which are arranged next to one another in a first direction, wherein two housing units arranged adjacent to one another in the first direction each enclose a receiving space in which at least one of the plurality of battery cells is arranged, wherein each housing unit comprises an intermediate wall, wherein one of the intermediate walls is located between two receiving spaces adjacent to one another in the first direction, wherein the receiving spaces comprise a first receiving space, wherein the battery arrangement comprises a clamping device by means of which the cell assembly is clamped in the first direction, and wherein the housing units adjacent to the first receiving space in the first direction can be detached from one another and the first receiving space can be opened, in particular without opening the other receiving spaces encompassed by the cell assembly.The first recording room can therefore be opened independently of the other recording rooms. This preferably also applies to the other recording rooms.

[0039] The advantages described for the method according to the invention and its embodiments apply equally to the battery arrangement according to the invention.

[0040] Furthermore, the invention also relates to a motor vehicle with a battery arrangement according to the invention or one of its embodiments.

[0041] The invention also includes further developments of the battery arrangement according to the invention that have features already described in connection with the further developments of the method according to the invention. For this reason, the corresponding further developments of the battery arrangement according to the invention are not described again here.

[0042] The motor vehicle according to the invention is preferably designed as a motor vehicle, in particular as a passenger car or truck, or as a passenger bus or motorcycle.

[0043] The invention also encompasses combinations of the features of the described embodiments. The invention therefore also encompasses implementations that each comprise a combination of the features of several of the described embodiments, unless the embodiments are described as mutually exclusive.

[0044] Exemplary embodiments of the invention are described below. Shown are: Fig. 1 a schematic representation of a battery arrangement in a side view in a not yet expanded state of the battery cells, according to an embodiment of the invention; Fig. 2 a schematic representation of the battery arrangement from Fig. 1 in a state in which the cells are swollen, according to an embodiment of the invention; Fig. 3 a schematic representation of the battery arrangement from Fig. 2, in which an auxiliary clamping device has been arranged, and whose clamping device is opened for replacing a battery cell, according to an embodiment of the invention; Fig. 4 a schematic representation of the battery arrangement from Fig. 3 with the battery cell now removed, according to an embodiment of the invention; and Fig. 5 a schematic representation of the battery module from Fig. 4, in which a new battery cell was now inserted into the position of the removed battery cell and the cell assembly was clamped again by means of a clamping device, according to an embodiment of the invention.

[0045] The exemplary embodiments explained below are preferred embodiments of the invention. In the exemplary embodiments, the described components of the embodiments each represent individual features of the invention that can be considered independently of one another, each of which also develops the invention independently of one another. Therefore, the disclosure is intended to encompass combinations of the features of the embodiments other than those shown. Furthermore, the described embodiments can also be supplemented by further features of the invention already described.

[0046] In the figures, the same reference symbols designate elements with the same function.

[0047] Fig. 1 shows a schematic representation of a battery arrangement 10 according to an exemplary embodiment of the invention. The battery arrangement 10 is in a first state Z1, in which the battery cells 12 encompassed by the battery arrangement 10 have not yet swelled or have barely swelled. The battery arrangement 10 also comprises a cell assembly 14 comprising the aforementioned battery cells 12, which are designed as prismatic battery cells. Furthermore, the cell assembly 14 comprises a plurality of housing units 16. These housing units 16 are constructed in a similar manner, so that only one of these housing units 16 will be described below: The housing unit 16 comprises an intermediate wall 18 and two outer walls 20, 22. The intermediate wall 18 connects the two outer walls 20, 22 to one another. The housing units 16 are also arranged next to one another in the x-direction illustrated here, which was previously also referred to as the first direction.In the present example, the intermediate wall 18, together with the two outer walls 20, 22, forms a double-T profile. Alternatively, it is also conceivable for the intermediate wall 18, together with the two outer walls 20, 22, to form a U-profile or C-profile. Both configurations make it possible to form receiving spaces, in particular cuboid-shaped receiving spaces 24, when the housing units 16 are arranged side by side in the x-direction. End-side receiving spaces 24' are each formed between a housing unit 13 and an end plate or pressure plate 26, which is part of a clamping device 28, which will be explained in more detail later.

[0048] The receiving spaces 24 are thus delimited in and opposite to the x-direction by the intermediate walls 18 of the housing units 16, and in and opposite to the z-direction shown by the outer walls 20, 22 of the housing units 16 adjacent to the receiving space 24. Furthermore, the outer walls 20, 22 of adjacent housing units 16 can overlap in the z-direction, in particular according to a continuous or only regional overlap in the y-direction. By overlapping the respective adjacent outer walls 20, 22 of two adjacent housing units 16, a fluid-tight housing cover layer and a fluid-tight base can also be provided. The overlapping regions can also comprise locking elements by means of which the individual housing units can be locked together and thus connected to one another in a form-fitting manner.In each of these receiving spaces 24, as well as in the end-side receiving spaces 24', a cell row 30 is arranged, which comprises at least one battery cell 12 and optionally a plurality of battery cells 12 arranged next to one another in the y-direction. Preferably, a single such cell row 30 is provided per receiving space 24, 24'. Therefore, within a receiving space 24, 24', preferably not a plurality of battery cells 12 are arranged next to one another in the x-direction. Between each two battery cells 12 arranged adjacent to one another in the x-direction, there is therefore an intermediate wall 18 of a corresponding housing unit 16.

[0049] Furthermore, the battery cells 12 are constructed as follows: They have two first sides 12a, which are opposite one another in the x-direction and represent the cell sides with the largest area. They also comprise two second cell sides 12b, which are opposite one another in the y-direction and are correspondingly smaller in area than the respective first cell sides 12a. A cell pole 32 of the battery cell 12 is arranged on each of the second cell sides 12b. Each battery cell 12 comprises two such cell poles 32, which are correspondingly located on the opposite second cell sides 12b. If a cell row 30 comprises several battery cells 12, their respective cell poles 32 face one another. This enables a particularly compact arrangement, especially in the y-direction, and a particularly space-saving contacting of the battery cells 12 of the same row 30 with one another.

[0050] In addition, cooling devices can advantageously also be integrated into the individual housing units 16. In particular, in the present case, each intermediate wall 18 has at least one or more cooling channels 36 through which a coolant can flow. Furthermore, each housing unit 16 can have a coolant supply connection and a coolant discharge connection, so that in cooling operation, the coolant is supplied to the cooling channels 36 via the coolant supply connection and discharged again via the coolant discharge connection. The coolant is preferably a liquid coolant. Optionally, at least one such cooling channel 36 can also be integrated into one or both outer walls 20, 22 of a respective housing unit 16.

[0051] This cell assembly 14 is further encompassed by a clamping device 28 encompassed by the battery assembly 10 to clamp the cells 12 together with respect to the x-direction. In this example, the clamping device 28 comprises two end-side pressure plates 26, which are arranged in and opposite to the x-direction on the end battery cells 12 of the cell assembly 14. These two end plates 26 are clamped together by means of at least one clamping element 34, such as a clamping band 34, or tie rods or the like. The clamping band 34 can be provided, for example, in the form of a belt or a sheet metal.In general, the tensioning band 34 can be made of metal or a plastic, in particular a fiber-reinforced plastic, for example a UD (unidirectional) tape, with which the cell composite 14 including the pressure plates 26 can be wrapped, in particular can be wrapped several times, wherein the unidirectional reinforcing fibers of this UD tape then lie parallel to the direction of travel of the band 34.

[0052] In this example, the clamping device 28 rests on a top and bottom side of the cell assembly 14 relative to the z-direction, as well as on a left and right side relative to the x-direction. The clamping device 28 thus completely surrounds and encircles the cell assembly 14 perpendicular to the illustrated y-direction. Other embodiments of such a clamping device 28 are also conceivable.

[0053] By means of such a clamping device 28, it is now advantageously possible to exert a compressive force F1 on the cell assembly 14. This counteracts the swelling pressure of the cells 12 during their service life or during charging. This is due to the fact that the cells 12 expand during their service life or during charging, as is exemplified in Fig. 2 is illustrated.

[0054] Fig. 2 shows in particular the battery arrangement 10 from Fig. 1 in a second state Z2, in which the battery cells 12 have already aged somewhat and have swelled accordingly in and against the x-direction. The cells 12 thus expand in the x-direction and bulge, particularly on their cell sides 12a with the largest surface area. The clamping device 28 ensures that the battery arrangement 10 as a whole is held in a defined installation space in the x-direction despite the swelling of the cells 12. Due to the swelling of the cells 12, the clamping device 28 consequently exerts a correspondingly greater compressive force F2 on the cell assembly 14. The second compressive force F2 is greater than the first compressive force F1.

[0055] This battery arrangement 10 advantageously enables an efficient replacement of one of the battery cells 12 in the event of a defect. This replacement method will now be described below with reference to Fig. 3 to Fig. 5 is explained in more detail.

[0056] Fig. 3 to Fig. 5 each show the battery arrangement 10, as it is used, for example, for Fig. 1 and Fig. 2, in different states during cell exchange.

[0057] In Fig. 3, the battery cell 12 to be replaced is additionally designated 12', and the receiving space in which this defective battery cell 12' is arranged is now designated 24", but can be designed as previously described for the receiving spaces 24. The receiving space in which this defective battery cell 12' is arranged is also referred to below as the first receiving space 24". The battery cell 12' to be replaced, which is also referred to as the first battery cell 12', can be, for example, a defective battery cell 12'. If a defect occurs in such a battery cell 12' in the cell assembly 14, this defective cell 12' can now advantageously be replaced simply and efficiently, without having to also replace or otherwise impair the other cells 12 arranged in other receiving spaces 24', 24, which are different from the first receiving space 24".

[0058] In this example, an auxiliary clamping device 38 is first arranged on the cell assembly 14. In the present example, the auxiliary clamping device 38 comprises two clamping clamps 38a, 38b. Furthermore, the outer sides of the outer walls 20, 22, which are thus remote from the receiving spaces 24', 24, 24", are each formed with coupling geometries, for example, protruding springs or projections or the like. These coupling geometries can be coupled with corresponding coupling elements 42 of the clamping device 28, for example, end-side hooks arranged on the free clamp ends.

[0059] The first clamp 38a, together with the intermediate wall 18 of a first housing unit 16 adjacent to the first receiving space 24", encompasses or encloses a first subassembly 14a of the cell assembly 14, and the second clamp 38b, together with the intermediate wall 18 of the further housing unit 16 adjacent to the first receiving space 24", encompasses or encloses a second subassembly 14b of the cell assembly 14.

[0060] These partial assemblies 14a, 14b can thus be clamped in the x-direction by the clamps 38a, 38b or generally by the auxiliary clamping device 38, and this clamping can in particular also be maintained when the clamping device 28 is released. This occurs after the auxiliary clamping device 38 has been attached. To release the clamping device 28, in the present case, the clamping band 34 is cut at one or more points. The cutting is illustrated here by the scissors 44, and the cutting line 46 is shown as an example in dashed lines. It is also preferred that the auxiliary clamping device 38 and the clamping band 34 do not overlap. The auxiliary clamping device 38, for example the one or more clamps 38a, 38b, can be arranged offset from the clamping band 34, for example in or opposite to the y-direction.As a result, the tensioning band 34 can be easily removed after cutting open while the auxiliary tensioning device 38 is still in place and can later be replaced with a new tensioning band 34.

[0061] Once the tensioning band 34 has finally been cut, the tensioning force F2 on the cells 12 of the respective subassemblies 14a, 14b is still maintained by the auxiliary tensioning device 38.

[0062] Subsequently, the first receiving chamber 24" is opened and the defective cell 12' is removed from the first receiving chamber 24".

[0063] Fig. 4 shows a schematic representation of the battery arrangement 10 from Fig. 3 in an open state of the first receiving space 24" with the defective cell 12' already removed. If several battery cells 12, 12' are arranged in the first receiving space 24", which do not necessarily all have to be defective, they are nevertheless all removed from the first receiving space 24" to replace the defective cell 12' and replaced with replacement cells 12" (cf. Fig. 5) is replaced, since these additional cells 12 located in the first receiving space 24" are also relaxed when the first receiving space 24" is opened, which can have a negative effect on their service life.

[0064] Subsequently, one or more replacement cells 12" can be inserted into the opened first receiving space 24", and the first receiving space 24" can be closed again by arranging the two partial assemblies 14a, 14b next to one another again. In addition, the clamping device 28 can again be arranged surrounding the cell assembly 14 with the at least one replacement cell 12". For this purpose, the clamping device 28 can be replaced as a whole or in parts by a new clamping device 28. In the present example, the clamping band 34, which was cut, was replaced by a new clamping band 34'. The pressure plates 26 are the same as before. Once the cell assembly 14 with the replacement cell 12" has once again been clamped by the clamping device 28 as intended, the auxiliary clamping device 38 can also be removed again.

[0065] Fig.5 shows a schematic representation of the battery assembly 10 with the replacement cell 12" in the first receiving space 24", wherein the auxiliary clamping device 38 has been removed again and the cell assembly 14 has been re-clamped by the clamping device 28. The clamping force F2 acting on the non-replaced cells 12 is greater than the pre-tensioning force F1 exerted on the replaced cell 12" by means of the clamping device 28, at least if the replaced cell 12" is a cell that is less swollen than the other cells 12, for example, a new battery cell 12". This reduced first clamping force F1 results automatically from the mutual support of the adjacent housing units 16 in the x-direction, as well as from the elastic properties of the partition walls 18.If the replaced cell 12" swells accordingly, its first cell sides 12a press with correspondingly greater force against the adjacent partition walls 18, which then compress elastically to some extent, resulting in a higher restoring force on the replacement cell 12".

[0066] If a cell 12' develops a cell defect in prestressed and corrugated cells 12, i.e., within a cell assembly 14, an auxiliary clamping device 38, for example, an external clamp or an external tension band, can advantageously be applied to molded pins as an example of the coupling geometry 40 or recesses in the outer walls 20, 22 as a further example of the coupling geometries 40, in order not to change, or at least not to completely lose, the prestress of the non-defective and non-replaceable cells 12 in receiving spaces 24', 24 other than the first receiving space 24". The original clamping device 28 can then be separated or otherwise released, and the system, in particular the first receiving space 24", can be opened locally. The defective cell 12' can then be removed, and a new cell 12", or generally a replacement cell 12", can be inserted.The new cell 12" can be pre-tensioned to the desired pre-tension force F1. In addition, new tensioning belts or tensioning plates 34' can be applied as tensioning device 28.

[0067] In particular, the examples show how the invention can provide a repair concept for a high-voltage battery at the cell level. T-profiles or U-profiles can be positioned between the battery cells of a vehicle's traction battery, for example for the housing units. These profiles can have a cooling function, electrical insulation, or even thermal insulation between the cells. The housing units can be made of metal, plastic, or fiber-reinforced plastic, for example. The profiles can be pre-tensioned together with the cells to form a cell module or cell stack and assembled using, for example, tensioning straps or tension struts. This connection is advantageously designed to be detachable. The profiles are preferably shaped above and below the cells in such a way that the respective cell is partially or completely covered by them.The cells, including the profiles, can be mounted using tension straps or tension rods. In the event of repairs, the profiles can be opened again and individual cells replaced. This does not relieve the tension on other aged cells in the battery system that have already expanded. The profile can accommodate one or more cells in a row along its length. The profiles can also be designed to be sealed, eliminating the need for additional covers and base plates. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2010 041 709 A1

[0002] CN 212380492 U

[0005]

Claims

[1] Method for replacing at least one first battery cell (12') in a cell assembly (14) with at least one second battery cell (12"), characterized by the steps: - Providing the cell assembly (14) as part of a battery arrangement (10) • which comprises, as part of the cell assembly (14), a plurality of prismatic battery cells (12, 12'), of which at least one represents the at least one first battery cell (12'), • which, as part of the cell assembly (14), has a plurality of housing units (16) arranged next to one another in a first direction (x), wherein two housing units (16) arranged adjacent to one another in the first direction (x) each enclose a receiving space (24, 24") in which at least one of the plurality of battery cells (12, 12') is arranged, wherein each housing unit (16) comprises an intermediate wall (18), wherein one of the intermediate walls (18) is located between each two receiving spaces (24, 24") adjacent to one another in the first direction (x), and wherein the receiving spaces (24, 24") comprise a first receiving space (24, 24") in which at least the at least first battery cell (12') is arranged; and • which comprises a tensioning device (28) by means of which the cell assembly (14) is tensioned in the first direction (x); - releasing the clamping device (28) in such a way that a connection between the two housing units (16) adjacent to the first receiving space (24") with respect to the first direction (x) is released and the first receiving space (24") is opened, and the cell assembly (14) is divided into at least two partial assemblies (14a, 14b) which each remain clamped in the first direction (x) during the opening of the first receiving space (24"); - Removing at least the first battery cell (12') from the opened first receiving space (24") and inserting at least the second battery cell (12") into the opened first receiving space (24"). [2] Method according to claim 1, characterized byin that each of the housing units (16) has a first outer wall (20) and a second outer wall (22) which delimit the receiving space (24, 24") with respect to a second direction (z), wherein the intermediate wall (18) connects the first and second outer walls (20, 22) to one another, in particular wherein the intermediate wall (18) forms a U-profile or a double-T profile with the outer walls (20, 22). [3] Method according to one of the preceding claims, characterized by that locking elements are arranged on a respective first and / or second outer wall (20, 22), by means of which locking elements the housing units (16) arranged adjacent to one another in the first direction (x) are coupled to one another, in particular are connected in a form-fitting manner. [4] Method according to one of the preceding claims, characterized by that the tensioning device (28) comprises a circumferential tensioning band (34) and / or a tension rod. [5] Method according to one of the preceding claims, characterized bythat before the tensioning device (28) is released, an auxiliary tensioning device (38) is arranged on the cell assembly (14), by means of which the partial assemblies (14a, 14b) are tensioned in the first direction (x). [6] Method according to one of the preceding claims, characterized by that a coupling geometry (40) is arranged on an outer side of a respective first and second outer wall (20, 22) facing away from the receiving space (24, 24"), which coupling geometry can be coupled to the auxiliary clamping device (28), wherein the auxiliary clamping device (28), in particular comprising at least two clamping clamps (28a, 28b), is coupled to the coupling geometries (40) of the housing units (16) adjacent to the first receiving space (24, 24") for clamping the partial assemblies (14a, 14b). [7] Method according to one of the preceding claims, characterized byin that in each receiving space (24, 24") a plurality of battery cells (12, 12') are arranged next to one another in a row (30) in a third direction (y), in particular wherein each of the battery cells (12, 12') has two first cell sides (12a) opposite one another in the first direction (x), which represent the cell sides (12a) with the largest area of ​​the six cell sides of the prismatic battery cell (12'), and two second cell sides (12b) opposite one another with respect to the third direction (y), on each of which a cell pole (32) is arranged. [8] Method according to one of the preceding claims, characterized by that after opening the first receiving space (24"), the plurality of battery cells (12, 12') located in the first receiving space (24") are removed from the first receiving space (24") and a plurality of second battery cells (12") are inserted into the first receiving space (24"). [9] Method according to one of the preceding claims, characterized bythat after the insertion of the at least one second battery cell (12"), the at least two partial assemblies (14a, 14b) are arranged on one another in such a way that the first receiving space (24") is closed, and the clamping device (28) or a second clamping device (28) for clamping the cell assembly (14) is arranged on the latter. [10] Battery arrangement (10) with a cell assembly (14) comprising a plurality of prismatic battery cells (12, 12'), characterized by , that - the cell assembly (14) has a plurality of housing units (16) arranged next to one another in a first direction (x), - wherein each two housing units (16) arranged adjacent to one another in the first direction (x) enclose a receiving space (24, 24") in which at least one of the plurality of battery cells (12, 12') is arranged, - wherein each housing unit (16) comprises an intermediate wall (18), - wherein one of the intermediate walls (18) is located between each two receiving spaces (24, 24") adjacent to each other in the first direction (x), - wherein the receiving spaces (24, 24") comprise a first receiving space (24, 24"), - wherein the battery arrangement (10) comprises a clamping device (28) by means of which the cell assembly (14) is clamped in the first direction (x), and - wherein the housing units (16) adjacent to the first receiving space (24") in the first direction (x) are detachable from one another and the first receiving space (24") is openable.

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