Energy storage device and cell holder for an energy storage device

Abstract

Cell holders (10, 110, 14) for multiple energy storage cells for use in an energy storage device, comprising: - a contact side (45) with a connecting surface (54), - a cell receiving side (44) facing away from the contact side, on which multiple cell receivings (108) are arranged, wherein several connecting projections (56) extend away from the cell receiving side starting from the connecting surface, and - several connecting recesses (52) extend towards the cell receiving side, wherein the connecting projections and the connecting recess each have a continuous fastening recess (126) which extends between the contact side and the cell receiving side through the cell holder, characterized in that the connecting recesses and the connecting projections are arranged alternately on an imaginary circle around a cell receiving.

Description

[0001] The invention relates to an energy storage device in which a plurality of energy storage cells are arranged between cell holders in at least two packing levels, and to a cell holder for an energy storage device.

[0002] For many applications of energy storage devices – such as in electromobility with vehicles equipped with electric drive components or in stationary operation for a remote energy supply – it has become clear that it is particularly cost-effective to assemble the energy storage system from a number of standardized energy storage cells in a tailored assembly. Due to the high production volumes achievable with standardized energy storage cells, such solutions tend to be more cost-effective than using application-specific, customized energy storage cells.

[0003] The voltage or battery capacity required for a desired application can then be set as desired by an appropriate arrangement, for example in several packing levels, and a suitable electrical connection of the energy cells.

[0004] Typically, modules are built from individual cells and then connected together. The cells are usually mechanically fixed within the module by a housing. The modules, consisting of several fixed cells, are then secured in a further housing.

[0005] German patent application DE 10 2011 119 253 discloses an energy storage device with multiple packing levels consisting of multiple axially parallel cells, wherein the mechanical and electrical connection of the cells in the individual packing levels is realized with a pin-socket connection arranged in the cell spaces.

[0006] One disadvantage of energy storage devices assembled from standard energy storage cells, compared to those with application-specific shaped energy storage cells, is that they can only be made sufficiently rigid to withstand deformation by means of a complex, rigid and, above all, space-consuming housing, in order to be used in space-limited application fields such as vehicles with electric drive components.

[0007] It is therefore an object of the invention to provide a deformation-resistant energy storage device with a high energy density.

[0008] This problem is solved according to the invention by an energy storage device in which a plurality of energy storage cells are arranged in at least two packing levels between at least one first cell holder and at least one second cell holder of the respective packing level, wherein at least one of the energy storage cells of one of the packing levels is electrically connected to a corresponding energy storage cell of at least one adjacent packing level to form a cell stack by means of at least one contact element arranged between the facing cell holders of the adjacent packing levels. Preferably, several, in particular all, energy storage cells of one of the packing levels are electrically connected to a corresponding energy storage cell of the adjacent packing level, so that several cell stacks are formed.

[0009] According to the invention, in particular the first and the second cell holders of the at least two packing levels each have at least one continuous fastening recess, wherein a fastening means under tension extends through these fastening recesses, by means of which at least the energy storage cells of the at least one cell stack, in particular all corresponding cell pairs or / or cell stacks of the two packing levels, are clamped together.

[0010] Preferably, a fastening recess of a first and a second cell holder, both of a first packing level and of an adjacent, second packing level, together form a fastening channel through which the fastening means extends.

[0011] The invention is based on the basic idea of ​​applying a compressive force to superimposed energy storage cells of adjacent packing levels of the energy storage device by means of the tension-bearing fastening means, which ensures the electrical connection of the facing poles of these energy storage cells, in particular via a contact element.

[0012] This eliminates the need to use conventional "modules" in which a small number of energy storage cells are shrunk into a plastic casing and often the individual energy storage cells are crimped, soldered, or welded together. An energy storage device according to the invention can therefore be constructed from one or more cell stacks and exhibit a significantly higher energy density than energy storage devices with pre-assembled modules, particularly because the housings of the individual modules are no longer required.

[0013] A further advantage of an energy storage device according to the invention is that it can be integrated into the force flow of its installation environment, whereby the corresponding forces can be transmitted not only through an outer housing of the energy storage device, but also through the clamped cell stacks. This is because the energy storage cells are arranged between two cell holders in their packing plane (i.e., held in the cell holders) and additionally clamped to form a cell stack, forces and / or moments from the installation environment can be transmitted through the energy storage device to a certain extent. The transmissible compressive forces are limited, in particular, by the compressive force that a single cell can withstand. If, for example, cells of type 18650 are installed – as intended – the transmissible compressive force, according to preliminary measurements, is approximately 1 kN per cell.

[0014] For example, if the energy storage device were used as a bicycle battery, it could be integrated into the seat tube of the bicycle, where it would absorb forces, thus allowing for a smaller frame. A similar integration of the energy storage device into load-bearing components is also planned for hybrid and / or electric vehicles.

[0015] In various designs, an energy storage cell with more than two packing levels and / or more than one first and / or second cell holder in at least one of the packing levels can also be specified.

[0016] To ensure the simplest possible application of the compressive force to the cell stack and / or to facilitate the installation of the fastening device, one embodiment features a fastening channel extending along a common longitudinal axis of the at least one fastening recess of the first and second cell holders, in particular through all packing levels of the cell stack. In this embodiment, straight tension rods can be easily used as the fastening device. Alternatively, the fastening recesses and the fastening channel can be designed with a curvature to match each other, which is advantageous in suitable installation environments, such as a bicycle frame. In such a case, a tension cable would preferably be used as the fastening device.

[0017] To optimize the integration of the energy storage device into a force flow of the installation environment, the fastening channel is formed through at least two packing levels, in particular through all packing levels of the cell stack.

[0018] In order for the tension-bearing fastener, in particular several tension-bearing fasteners, to transmit a compressive force to the cell stack(s), the fastener and cell stack must be connected to each other for force transmission. To ensure this, the energy storage device has an end plate on an outer cell holder of a first packing level and / or a last packing level, in particular of one or all cell stacks, to which the fastener is attached and / or folded. The end plate then exerts a direct or indirect force, through the tensile force of the fastener, on the adjacent energy storage cell or the associated outer cell holder of the outermost packing level.

[0019] Despite the fact that an end plate is provided according to this design, simple electrical contacting of the energy storage cells from outside the energy storage device must be possible. For this purpose, the end plate preferably has at least one recess for the at least one fastening element and / or at least one recess for a conductive element that is electrically connected to a contact element of the outer cell holder of an outermost packing level.

[0020] According to one embodiment, particularly with a relatively large number of energy storage cells per packing level, several fastening passes, especially through several or all packing levels, are provided to ensure a reliable pressing force for electrical connection for all cell stacks and / or energy storage cells.

[0021] To ensure the application of sufficient pressure to cell stacks arranged inside a packing plane, according to one embodiment, at least one fastening path runs between at least two cell stacks, in particular such that this fastening path is arranged further away from an outer boundary of the energy storage device in at least one of the packing planes than at least one energy storage cell of that packing plane. In such an embodiment, for example, a plurality of fastening paths, each with a fastening element, can run through a packing surface of a packing plane at substantially equal intervals, thereby exerting a substantially equal pressure on all cell stacks of that packing plane.

[0022] In particular, to enable the parallel electrical connection of several cell stacks, according to one embodiment, the contact elements of several cell stacks between two adjacent packing planes are electrically connected to each other to form a contact element group. Preferably, a parallel-connected cell stack group is formed by means of the contact element group.

[0023] In order to enable an electrical parallel connection of several cells, according to one embodiment the contact elements of several cells in a packing plane can also be electrically connected to each other to form a contact element group.

[0024] For example, the number of packing levels in a cell stack can be used to set a desired nominal voltage of the energy storage device, while the number of cell stacks or cells connected by means of a contact element group can be used to set a desired nominal capacity of the energy storage device.

[0025] According to one embodiment, at least one contact tab for connection to a battery management system (BMS), a sensor, and / or another contact element is arranged on a contact element and / or a group of contact elements. If such a contact tab is arranged at the edge of a contact element or group of contact elements, this can facilitate the application of a BMS, a sensor, or another contact element.

[0026] In one embodiment, a temperature sensor can be arranged in at least one fastening channel instead of or in addition to a fastening means, in particular to measure the temperature inside the energy storage device.

[0027] In order to accommodate different requirements such as the compressive force to be applied between the energy storage cells, the geometry of the installation environment and / or mounting boundary conditions, the fastening device has a tension strut and / or a tension cable in one version.

[0028] A tension strut can be designed, for example, like a simple bicycle spoke, made of a metallic material and / or a plastic material, possibly reinforced. A tension cable can be made of spring steel or a plastic with elastic properties and may contain reinforcing fibers.

[0029] In order to enable cost-effective production even in high quantities, according to one embodiment a first cell holder of a packing level and a second cell holder of an adjacent packing level facing this first cell holder are integrally connected to each other to form a double-sided cell holder, wherein at least one contact element is arranged between the two sides of the double-sided cell holder.

[0030] In order for the cell stacks to be clamped together in accordance with the invention (i.e., so that compressive force can be exerted on the individual energy storage cells of the cell stack by means of the fastening means), it may be necessary to determine the position of the energy storage cells in their packing plane and / or to align the position of corresponding energy storage cells of different packing planes with each other, in particular in the sense of a coaxial alignment. According to one embodiment, the cell holders of a packing plane have a cell receptacle on a cell receptacle side for each energy storage cell assigned to them, wherein the cell receptacle side of a first cell holder faces that of a second cell holder, in particular such that an energy storage cell can be received at its two opposite ends.

[0031] In particular, for the arrangement of a contact element, the cell holders in one embodiment have a contact side facing away from a cell receiving side, wherein the contact sides of cell holders arranged adjacent to each other in neighboring packing planes each have a connecting surface facing the other contact side. The connecting surface is also specifically designed to transfer the compressive force acting between adjacent energy storage cells of a cell stack to the contact element and thus fix it, for example, in a plane parallel to a packing plane. Preferably, at least one contact element is arranged between the mutually facing connecting surfaces.

[0032] To reliably position the adjacent cell holders of two neighboring packing levels relative to each other, according to one embodiment, a first cell holder and an adjacent second cell holder are aligned relative to each other by means of a connecting projection on either the first or the second cell holder. This connecting projection extends from the connecting surface of the second cell holder and is at least partially received in the at least one mounting recess of the adjacent cell holder. By aligning the cell holders of different packing levels relative to each other, a coaxial alignment of one or more cell stacks with respect to the longitudinal axis of the energy storage cells of the cell stack can be ensured.

[0033] If, according to one embodiment, the connecting projection is designed with a continuous recess, particularly as part of a fastening recess, the connecting projection can also serve as a guide and / or as a passage for a fastening element.

[0034] To ensure reliable positioning of all cell holders in the energy storage device, one embodiment provides at least one connecting projection on each first and / or second cell holder, preferably with a continuous recess. In another embodiment of the energy storage device, it may be desirable to manufacture the first and second cell holders from a single mold, for example, using an injection molding process. In this embodiment, the connecting projections on the first and / or second cell holders are each associated with a mounting recess of the adjacent cell holder, which does not have a connecting projection.

[0035] To facilitate electrical insulation, at least one mounting recess is positioned at a distance from the cell recesses and / or the contact element. This allows, for example, the use of a conductive material for the mounting device, because contact between the mounting device and the cell recesses and / or the contact element is prevented from the outset.

[0036] According to one embodiment, several mounting recesses are arranged between the cell recesses according to a predetermined pattern, particularly at regular intervals, preferably in the circumferential direction, on an imaginary circle around a cell receptacle. Such a design allows the use of fewer or even a single "basic" cell receptacle for very different geometries of an energy storage device, thus saving costs for the design and manufacture of the cell receptacles.

[0037] To enable a simple design of the contact element, it has a conductive metal sheet, in particular with an iron, brass, copper and / or aluminum active material.

[0038] According to one embodiment, the contact element is shaped such that it can be positioned on and / or around at least one connecting projection. This ensures precise alignment of the contact element on a cell holder. For example, the contact element can have at least one recess into which it can be inserted onto the connecting projection.

[0039] To facilitate the formation of the cell stacks, the corresponding energy storage cells are arranged at least essentially coaxially with respect to a longitudinal axis of the energy storage cells that runs perpendicular to the packing planes in one embodiment.

[0040] To enable a space-saving energy storage device, particularly one with the highest possible energy density, the longitudinal axes of the mounting channels and the energy storage cells are arranged essentially parallel to each other. Also for space optimization, according to one embodiment, the energy storage cells are arranged hexagonally or in a matrix pattern next to each other in their packing plane.

[0041] To utilize widely available and therefore cost-effective standard energy storage cells, the energy storage cells have a shape that is at least substantially cylindrical. Preferably, only one type of energy storage cell is used in an energy storage device, in particular type 18650. However, other common types of energy storage cells, especially cylindrical ones, can also be used in accordance with the invention.

[0042] According to another aspect of the invention, a cell holder for several energy storage cells is proposed, in particular, but not exclusively, for use in an energy storage device according to one embodiment of the invention.

[0043] A cell holder according to this aspect has a contact side with a connecting surface and a cell receiving side facing away from the contact side, on which several cell receiving surfaces are arranged.

[0044] In the cell holder, at least one connecting projection extends from the connecting surface away from the cell receiving side and at least one connecting recess extends towards the cell receiving side.

[0045] The at least one connecting projection and the at least one connecting recess each have a continuous fastening recess which extends between the contact side and the cell receiving side through the cell holder, in particular through it.

[0046] This design, particularly with a suitable arrangement of the connection recess and the connection projection relative to each other, allows for the simple attachment of two cell holders at their contact surfaces. Furthermore, an energy storage device can be designed with only one type of cell holder, resulting in significant cost savings.

[0047] Advantageous embodiments of the invention are set forth in the dependent claims; exemplary embodiments can be found in the following descriptions in conjunction with the figures. The figures show in detail:

[0048] Fig. 1 in a sectional view a section of an energy storage device according to an embodiment of the invention with energy storage cells in three packing levels and with two continuous fastening means;

[0049] Fig. 2 in an upper perspective view a cell holder according to one embodiment of the invention;

[0050] Fig. 3 the cell holder out Fig. 2 in a lower perspective view;

[0051] Fig. 4 a contact element for use in an energy storage device according to one embodiment of the invention;

[0052] Fig. 5 in a perspective view an exemplary arrangement of energy storage cells in an energy storage device according to an embodiment of the invention;

[0053] Fig. 6 in a perspective view an energy storage device according to an embodiment of the invention with a single contact element arranged between two packing planes;

[0054] Fig. 7 in a perspective view an energy storage device according to an embodiment of the invention with a double contact element between two packing planes;

[0055] Fig. 8 in a partially cutaway perspective view an energy storage device according to an embodiment of the invention with a cover plate; and

[0056] Fig. Figure 9 shows a perspective view of the top of an energy storage device according to an embodiment of the invention with a cover plate.

[0057] In Fig. 1 is an energy storage device 5 with three packing levels 1 , 2 , 3 depicted, in each of which a plurality of energy storage cells 4.1a -c, 4.2a -c and 4.3a –c is arranged in a matrix-like distribution. In Fig. 1 are in the x-direction (see coordinates) in each of the packing planes 1 , 2 and 3 Each has three energy storage cells 4arranged. A plurality of energy storage cells (not shown) are also arranged in the y-direction, so that, together with the extension in the z-direction over three packing planes, the energy storage device essentially has a cuboid shape. 5 results.

[0058] The energy storage cells 4 each packing level 1 , 2 and 3 are at their upper end with the protruding battery contact 6 each in a cell image 8 of a first cell holder 10 recorded. The other axial end of each energy storage cell 4 is each in a cell image 12 a second cell holder 14 recorded.

[0059] The cell images 8 of the first cell holder 10 each packing level 1 , 2 and 3 as well as the cell images 12 of the second cell holder 14each packing level 1 , 2 and 3 are designed in such a way that corresponding energy storage cells (here e.g. 4.1a , 4.2a and 4.3a , likewise with b or c) are arranged coaxially to each other with respect to a central longitudinal axis L.

[0060] In the presentation of the Fig. 1 above the first packing level 1 The energy storage device is equipped with an upper end plate 16 completed; below the packing level 3 through a lower end plate 18 .

[0061] Between the upper end plate 16 and the energy storage cells 4.1 the first packing level 1 as well as between the packing levels 1 and 2 , the packing levels 2 and 3 and between the packing level 3 and the lower end plate 18 Each is a contact element 20inserted, whereby the contact elements 20.2 and 20.3 are trained to operate the energy storage cells 4.x to electrically connect adjacent packing planes. The contact elements 20.1 and 20.4 are designed to house the energy storage cells of one of the outer packing levels 1 and 3 by means of a guiding element 22.1 or 22.4 with an electrical connection outside the energy storage device 5 to connect.

[0062] The contact elements 20 In the region of the central longitudinal axis L of the cell stacks a, b and c (or parallel to it) each exhibit a thickening at the connection point between two energy storage cells of different packing levels. 24 or a depression (not shown here) that supports the electrical connection.

[0063] In the x-direction between the cell stacks a and b or b and c, each of the one-piece formed first cell holders has 10.1 , 10.2 and 10.3 as well as each of the one-piece formed second cell holders 14.1 , 14.2 and 14.3 a mounting recess 26 or 28 which is shown in detail A for better visibility. All mounting recesses. 26 , 28 The first cell stack a and the second cell stack b are arranged coaxially on an axis parallel to the axis L. This also applies analogously to the mounting recesses. 26 and 28 the different packing levels 1 – 3 between the second cell stack b and the third cell stack c. Also in the end plates 16 and 18 Corresponding coaxial recesses are provided.

[0064] Thus, the representation of Fig. 1 two fastening channels each formed by coaxial fastening recesses 30.1 and 30.2 along the z-direction through the entire energy storage device 5 , in particular also through the corresponding mounting recesses of the cell holders 10.1 until 10.3 and 14.1 until 14.3 .

[0065] Through each of the fastening channels 30.1 and 30.2 is a fastening device designed as a metal strut 32.1 or 32.2 guided, which has an external thread at both ends. By means of nuts 34 and locknuts 36 , which are located on each z-side of the energy storage device 5 The fasteners are screwed onto the respective external thread of the fastener, thus clamping the fasteners. 32 the energy storage device 5 and thus, in particular, the cell stacks a, b, and c together.

[0066] To the extent that the fasteners 32 The fully assembled energy storage device is placed under tensile stress. 5 under a corresponding compressive stress, which is exerted in particular by the nuts 34 on the end plates 16 and 18 is transmitted, and from these via the metallic contact elements 20 on the battery contacts 6 and the opposing battery contacts of each cell stack.

[0067] This ensures, firstly, the electrical contact between the energy storage cells of the individual packing levels of each cell stack by means of the contact elements. 20 This is ensured because sufficient pressure can be applied. Furthermore, the tensioning of the different packing levels of the energy storage device ensures... 5for increased mechanical stability of the energy storage device against bending forces, bending moments, shear forces, shear moments and / or torsional moments applied to the energy storage device from the outside.

[0068] The cell holders 14.1 and 10.2 as well as 14.2 and 10.3 are connected by means of connecting projections 38 of the first cell holder involved 10.1 or 10.3 in a mounting recess, which may be widened and / or made elastic 28 of the second cell holder involved 14.1 or 14.2 positioned with respect to a determination in the x and y directions.

[0069] The connecting protrusions 38 They also serve to roughly define the contact elements. 20 , which circular recesses 40 exhibiting features with which they can be used to work around the connecting projections during assembly 38 be inserted.

[0070] In the energy storage device 5 according to Fig. Figure 1 shows an exemplary, very simple circuit in which (in the illustration) the three energy storage cells of each packing level are electrically connected in parallel to a cell group, which are connected by means of the associated contact elements. 20 They are connected in parallel. The other packing levels, which are connected in parallel in an analogous manner, are connected in series with them, so that a contact element group is formed which forms the energy storage device. 5 the increased capacity of the parallel connection of three cells and the increased voltage of the pure connection of three packing levels provides.

[0071] In this embodiment, cylindrical cells of type 18650 are used as standard. On the contact element 20.3 The contact tab on the right is an example. 42indicated, which in accordance with the invention may also be provided on each or some contact elements and may serve as a connection for a battery management system and / or a temperature, current and / or similar sensor (not shown here).

[0072] In Fig. 2 is a cell holder 110 The illustration shows multiple energy storage cells for use in an energy storage device. The cell holder 110 has a cell uptake side 44 on, at which several cell images 108 are arranged. The cell images 108 They have an essentially circular cross-section to accommodate a cylindrical energy storage cell, which is not shown here. For improved fixation in the cell holder. 108 small bulges can occur 46 be included in every cell recording.

[0073] The individual cell images 108are arranged in a hexagonal pattern, so that for each inner cell image, six further cell images are equidistant on an imaginary circle around the center of the middle cell image 108 are arranged. At the nodes 48 the bridges remaining between the cell images 50 Each is a connecting recess. 52 trained (see Fig. 3), wherein each of the connecting recesses is part of a continuous fastening recess 126 is formed, which is located between the cell uptake side 44 and one from Fig. 3 visible contact page 45 through the cell holder 110 extends.

[0074] Out of Fig. 3 shows that the contact page 45 a connecting surface 54 exhibits connecting projections extending from which 56 away from the cell uptake side 44and connecting recesses 52 towards the cell uptake side 44 extend.

[0075] The connecting projections as well 56 are designed in such a way that they are hollow inside, forming part of the mounting recess 126 represent.

[0076] The connecting recesses 52 are so widened and / or elastic that they form a connecting protrusion 56 a second cell holder also designed according to this embodiment of the invention 110 can absorb. Through the alternating formation of connecting projections. 56 and connecting recesses 52 in the Fig. 2 and Fig. The embodiment shown in 3 thus enables an energy storage device with identically designed first and second cell holders. 120 can be equipped, which can lead to significantly lower manufacturing costs and simpler assembly logistics.

[0077] In Fig. 4 is an example contact element 20 illustrated according to one embodiment of the invention. It is evident that smaller recesses 40 for positioning the contact element made with a metal sheet 20 are provided on the cell holders. Thickenings are also included. 24 designed to ensure electrical contact between the corresponding energy storage cells of adjacent packing levels, between which the contact element 20 is inserted. The thickenings 24 of the contact element 20 These are formed here by a deformation of the metal sheet out of its main plane. At the contact element 20 are also guiding elements 22 and a contact tab 42 planned.

[0078] A simplified schematic representation of a hexagonal arrangement of cylindrical energy storage cells 4 in three packing levels1 , 2 and 3 according to Fig. 5 should in particular describe the arrangement of the energy storage cells 4 an associated energy storage device, for example with cell holders 110 according to the Fig. 2 and Fig. 3 and / or with one or more contact elements 20 according to Fig. 4 per transition between adjacent packing levels 1 and 2 or 2 and 3 , represent.

[0079] In Fig. 6 is an energy storage device 5 shown in a partially cutaway section, where it is evident that in each packing level 1 and at least 2 a large number of energy storage cells 4 is installed in a hexagonal arrangement. Between the second cell holder 14 the first packing level 1 and the first cell holder 10 the packing level 2is the same as for the upper contacting of the energy storage cells 4 the packing level 1 a single contact element 20 arranged, which forms the connection between the packing levels or between the top packing level 1 and should ensure an electrical connection.

[0080] In contrast, in the energy storage device 5 according to Fig. 7 between the packing levels 1 and 2 as well as for the upper electrical connection of the packing level 1 a double contact element 201 and 202 installed, which is what the manufacturing of the individual contact elements entails 201 and 202 simplified. The thickenings 24 They only need to be inserted into the base plate in one direction.

[0081] In Fig. 8 is an energy storage device 5 with a partially cut end plate 16This illustrates how the fasteners 32 above the end plate 16 with spoke nipples 34 , 36 to be fastened, with tensile stress being applied simultaneously by the screwing. It is also evident that the end plate 16 Exclusions 58 to accommodate a connecting projection 56 features which also serve, among other things, to position the end plate.

[0082] Out of Fig. 8 is also evident that in an energy storage device 5 the energy storage cells 4 a packing level 1 with separate contact elements 203 and 204 can be contacted at the location marked with the reference numbers 60The designated points are spaced apart from each other and therefore not electrically connected. This allows for more complex circuits to be implemented in the energy storage device, where, for example, a voltage build-up first occurs in one direction across several packing levels and then in the other direction across several packing levels of the energy storage device, provided the circuitry is appropriate.

[0083] In Fig. 9 is a top view of a cover plate 16 with a variety of fasteners 32 depicted. QUOTES INCLUDED IN THE DESCRIPTION

[0084] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0085] DE 102011119253

[0005]

Claims

[1] Energy storage device ( 5 ), in which at least two packing levels ( 1 , 2 , 3 ) each a plurality of energy storage cells ( 4 ) between a first cell holder ( 10 , 110 ) and a second cell holder ( 14 ) are arranged at the respective packing level at least one of the energy storage cells of one of the packing levels by means of at least one contact element ( 20 ), which is arranged between the facing cell holders of adjacent packing levels, is electrically connected to a corresponding energy storage cell of at least one adjacent packing level to form a cell stack, characterized by that the first cell holders and the second cell holders of at least two packing levels each have a continuous fastening recess ( 26 , 28) exhibiting a fastening element under tension passing through the fastening recesses of these cell holders ( 32 ) extends, by means of which at least the energy storage cells of the at least one cell stack (a, b, c) are connected. [2] Energy storage device according to claim 1, wherein a fastening channel is formed along a common longitudinal axis of the fastening recesses of this cell holder. [3] Energy storage device according to one of the preceding claims, wherein a fastening channel is formed through all packing levels. [4] Energy storage device according to one of the preceding claims, comprising an end plate on an outer cell holder of a first packing level and / or a last packing level ( 16 , 18 ) exhibits, on which the fastening element is fixed and / or deflected. [5] Energy storage device according to one of the preceding claims, wherein at least one contact tab is located on a contact element and / or on a contact element group ( 42 ) is arranged for connection to a BMS, a sensor and / or another contact element. [6] Energy storage device according to one of the preceding claims, wherein the fastening means comprises a tension strut and / or a tension cable. [7] Energy storage device according to one of the preceding claims, wherein a first cell holder of a packing level and a second cell holder of an adjacent packing level facing this first cell holder are integrally connected to each other to form a double-sided cell holder, wherein the at least one contact element is arranged between the two sides of the double-sided cell holder. [8] Energy storage device according to one of the preceding claims, wherein the cell holders of a packing level provide a cell receptacle for each energy storage cell assigned to them ( 8 , 12 ) on a cell uptake side, wherein the cell uptake side of a first cell holder faces that of a second cell holder. [9] Energy storage device according to one of the preceding claims, wherein a first cell holder and an adjacent second cell holder are aligned to each other by means of a connecting projection on one of the cell holders, which extends from the connecting surface of one cell holder and which is at least partially received in the at least one mounting recess of the adjacent cell holder. [10] Energy storage device according to one of the preceding claims, wherein the at least one fastening recess is arranged spaced apart from the cell recesses and / or the contact element. [11] Energy storage device according to one of the preceding claims, wherein several fastening recesses are arranged between the cell recesses according to a predetermined pattern, in particular at regular intervals on an imaginary circle around a cell receptacle. [12] Energy storage device according to one of the preceding claims, wherein the contact element is shaped such that it can be positioned on at least one and / or around at least one connecting projection. [13] Energy storage device according to one of the preceding claims, wherein the corresponding energy storage cells are arranged at least substantially coaxially with respect to a longitudinal axis of the energy storage cells perpendicular to the packing planes. [14] Energy storage device according to one of the preceding claims, wherein the longitudinal axes of the fastening channels and the energy storage cells are substantially parallel. [15] Cell holder (10 , 110 ) for multiple energy storage cells for use in an energy storage device, in particular according to one of the preceding claims, comprising – a contact page ( 45 ) with a connecting surface ( 54 ), – one of the cell uptake sides facing away from the contact side ( 44 ), in which several cell images ( 108 are arranged, in which, starting from the connecting surface – at least one connecting advantage ( 56 ) extends away from the cell uptake side, and – at least one connecting recess ( 52 ) extends towards the cell uptake side, characterized by that the at least one connecting projection and the at least one connecting recess each have a continuous fastening recess ( 126) exhibiting a gap that extends between the contact side and the cell reception side through the cell holder.

Images