Energy module for an energy storage device of an electrically driveable motor vehicle, energy storage device, and motor vehicle

Abstract

The invention relates to an energy module for an energy storage device of an electrically driveable motor vehicle, wherein the energy module has a plurality of stacks; each of the stacks has a layered arrangement of battery cells characterized by a stacking direction; each of the battery cells has a layer structure with a solid-state electrolyte; the layer structure of each of the battery cells within a stack is oriented according to the stacking direction; and the plurality of stacks are arranged next to one another in such a way that a force and / or a pressure can be transferred from a first stack of the stacks to an adjacent second stack of the stacks, and the first stack and the second stack have different stacking directions from one another.

Description

[0001] 24-1456

[0002] 1

[0003] Energy module for an energy storage device of an electrically powered motor vehicle,

[0004] Energy storage device, motor vehicle

[0005] The present disclosure relates to an energy module for an energy storage device of an electrically powered motor vehicle. The disclosure relates equally to an energy storage device for an electrically powered motor vehicle and to an electrically powered motor vehicle itself.

[0006] Such an energy storage device typically comprises a plurality of battery cells connected in parallel and / or series, thus forming a high-voltage storage system for the vehicle, also known as a traction battery. The energy storage device is designed to discharge the battery cells and provide electrical energy to operate the vehicle and / or to supply electrical energy externally, for example via a charging station, and to be supplied with electrical energy via the charging station and / or through recuperation during driving in order to charge the battery cells of the energy storage device.

[0007] Several architectures for constructing such an energy storage device are known. For example, it is known to provide energy modules with battery cells and to build the energy storage device with multiple energy modules. It is also known to provide exactly one energy module with battery cells and to build an energy storage device with this single energy module; this is known as the cell-to-pack architecture. In addition to the energy module(s), an energy storage device typically also includes, for example, a battery control unit and structural elements, such as a housing.

[0008] Solid-state battery cells are used as an energy storage device, particularly for electric vehicles, to increase the energy density of lithium-ion (LiB) batteries at a given safety level compared to liquid-electrolyte battery cells. These solid-state battery cells are assembled in layers or as electrode stacks, with a battery cell consisting of individual layers: an anode layer, a separator layer containing a solid electrolyte, and a cathode layer. Such a battery cell is also referred to as a single cell. 24-1456

[0009] 2

[0010] The individual layers can be flat and stacked parallel to each other. Several individual cells are also stacked and combined to form a space-saving stack. This stack can be called a pouch cell or a prismatic cell.

[0011] For an energy storage device for an electrically powered vehicle, several individual stacks are assembled in a specific arrangement. To ensure sufficiently good contact between the individual layers, particularly between the solid electrolyte and the active materials of the anode and / or cathode, pressurization perpendicular to the layers is necessary. More precisely, good contact means that the charge carriers (ions) can overcome the boundary layers between the individual layers—microscopically, between the particles—with reduced electrical resistance. An increase in pressure through pressurization reduces this resistance. Furthermore, good contact also means that the contact is as homogeneous as possible across the entire contact surface.

[0012] In solid-state electrolyte battery cells, the anode is designed, for example, as a lithium metal anode (LMA) and / or sodium metal anode (NMA) to benefit from the comparatively high energy density of this anode type. Instead of an active material into which lithium can intercalate, elemental lithium metal is used.

[0013] When battery cells are cycled, i.e., charged and discharged, the active materials (including lithium metal), especially those of the anode, undergo expansion and contraction. This mechanical behavior necessitates adjusting the pressure so that the pressure level remains nearly constant even during expansion and / or contraction.

[0014] DE 102023107490 A1 discloses an electrochemical electrode arrangement for a solid-state battery, comprising a layer sequence with at least one first electrode current collector, a first electrode, a solid electrolyte, and a second electrode. The first current collector has an elastic and conductive material with a defined force-to-displacement function and is configured to exert pressure on the layer sequence.

[0015] According to DE 102021 107991 A1, a battery module for storing electrical energy is described, wherein the battery module comprises one or more battery cells that are between two24-1456

[0016] 3

[0017] Pressure plates are arranged side by side along the transverse axis of the battery module. The battery module is designed such that the distance between the two pressure plates can be varied within a specified range, thus allowing for changes in the spatial distribution of one or more battery cells along the transverse axis. Furthermore, the battery module is designed such that the two pressure plates exert a pressure force on the one or more battery cells throughout the entire range of available space.

[0018] It is known to apply pressure, also called stack pressure, using pre-tensioned compensating pads, coil, leaf, and / or gas springs, and / or hydraulic devices. The pressure is applied exclusively perpendicular to the battery layers to ensure good contact. Fincher CD, Athanasiou CE, Gilgenbach C, Wang M, Sheldon BW, Carter WC, et al. “Controlling dendrite propagation in solid-state batteries with engineered stress”. ChemRxiv. 2022; doi:10.26434 / chemrxiv-2022-0mmvj describes the inhibition and / or deflection of dendrite growth by mechanical stress. Chen YT, Jang J, Oh JAS, Ham SY, Yang H, Lee DJ, et al. “Enabling Uniform and Accurate Control of Cycling Pressure for All-Solid-State Batteries”. ChemRxiv. 2023; doi:10.26434 / chemrxiv-2023-8s8zw describes a significant increase in reversible discharge capacity with constant Coulomb efficiency through the application of cyclic pressure.These publications also describe how, in addition to perpendicular stack pressure, compressive stresses in the layers can be advantageous with regard to inhibiting dendrite growth and increasing the reversible discharge capacity.

[0019] The cycle stability of solid-state electrolyte battery cells, that is, their robustness against degradation during repeated charging and discharging, can still be improved in practical applications. In particular, lithium dendrites, originating from, for example, the LMA, can, despite the high strength, work their way through the solid electrolyte after only a few cycles and cause a short circuit in the battery cell.

[0020] Furthermore, the decrease in reversible discharge capacity with increasing cycle count may be in need of improvement. This can be attributed to a loss of contact or an increase in resistance between the active materials and the solid electrolyte during the repeated expansion and contraction of the cycling process.

[0021] In light of this prior art, one objective of the present disclosure is to specify a device which is suitable for enriching the prior art and improving at least the aspects of the prior art mentioned above. 24-1456

[0022] 4

[0023] In particular, the purpose of the disclosure is to provide an improved arrangement of battery cells with solid electrolytes that enables improved cycle stability.

[0024] The problem is solved by the features of the independent claims. The dependent claims contain further developments of the disclosure.

[0025] The problem is then solved according to one aspect of the disclosure by an energy module for an energy storage device of an electrically powered motor vehicle, wherein the energy module has a plurality of stacks; each of the stacks has a layered arrangement of battery cells characterized by a stacking direction; each of the battery cells has a layered structure with a solid electrolyte; the layered structure of each of the battery cells within a stack is oriented according to the stacking direction; and the plurality of stacks are arranged side by side such that a force and / or pressure can be transmitted from a first stack of stacks to an adjacent second stack of stacks, and the first stack and the second stack have different stacking directions from each other.

[0026] To improve the robustness of solid-state battery cells (i.e., battery cells with a solid electrolyte) against dendrite growth, a major degradation mechanism, and to further reduce the decrease in reversible discharge capacity, arrangements of solid-state battery cells within an energy module, particularly for electric vehicles, are proposed. It has been recognized that it is practically possible to arrange the battery cells in such a way that, in addition to vertical compressive stresses (i.e., parallel to the stacking direction), perpendicular compressive stresses (i.e., perpendicular to the stacking direction or within the layers of the layered structure) can also be present.

[0027] For this purpose, the stacks, and thus the battery cells and their layers, are arranged with different stacking directions. A force can act from the first stack to the second stack and vice versa, and the stacking direction of the first stack differs from that of the second. An external application of pressure and / or force, due to the intended stacking arrangement, causes each stack to experience a vertical force and a force perpendicular to it. In other words, each stack experiences a force in the stacking direction and a force perpendicular to it. This induces a mechanical stress in each stack, which can counteract dendrite growth. Furthermore, this arrangement minimizes any potential relative movement of the stacks during cycling.24-1456

[0028] 5

[0029] This results in minimal mechanical stress on the stacks or battery cells.

[0030] Overall, the proposed arrangement or energy module results in a particularly cycle-resistant energy module.

[0031] Optionally, each stack has a leveling layer oriented in the same direction on an outer surface of the stack. This ensures that pressure is applied as homogeneously as possible across the respective surfaces. In other words, a rigid leveling layer or plate is optionally proposed as the final layer of each stack. This leveling plate compensates for manufacturing deviations and / or tolerances in the dimensions of the battery cells.

[0032] Optionally, the energy module includes a pressure device; the pressure device is configured to apply a force and / or pressure to the majority of the stacks. In other words, pressure plates are proposed around the energy module to apply pressure as homogeneously as possible to the stacks. Such external printing or clamping is possible with constant force per unit area, constant distance, and / or a combination thereof.

[0033] Optionally, the stacks are arranged in a plane and / or two-dimensionally; and adjacent stacks have alternating stacking directions. The resulting application of pressure can also be described as hydrostatic or isostatic printing in a plane perpendicular to the layers and in a direction within the layers. This allows the energy module to be arranged in a relatively space-efficient manner, and electrical contacting of the battery cells is comparatively simple and effective.

[0034] Optionally, the stacks are arranged spatially and / or three-dimensionally; adjacent stacks exhibit a non-constant sequence of stacking directions; and within a row, column, and column, stacks with all stacking directions are provided. The resulting application of pressure can also be described as hydrostatic or isostatic printing in space perpendicular to the layers and in both directions within the layers. This enables multidimensional printing within the layers.24-1456

[0035] 6

[0036] Optionally, the arrangement of several stacks is geometrically characterized by a unit cell; and the energy module exhibits a translationally symmetric arrangement of stacks according to the unit cell. The unit cell allows for the definition of a transformation with a larger number of stacks of elementary arrangements, which serve as basic building blocks for larger arrangements.

[0037] Optionally, the stacks contain at least partially different numbers of battery cells. It was observed that the stack arrangements expand and / or contract uniformly in all spatial directions during cycling. It is important to consider that the expansion and / or contraction occurs to a different extent in the layer plane (perpendicular to the stack direction) compared to the vertical direction (in the stack direction). This can be taken into account to position the stacks relative to each other and to determine how many battery cells are stacked per stack. Therefore, the number of battery cells can vary between the stacks.

[0038] Optionally, a volume is provided between four adjacent stacks in a two-dimensional arrangement. Alternatively or additionally, a volume is provided between eight adjacent stacks in a three-dimensional arrangement. The volumes can be designed such that no collision of the individual stacks occurs during cycling, thus preventing pressure inhomogeneities.

[0039] According to one aspect of the disclosure, an energy storage device for an electrically powered motor vehicle is provided, wherein the energy storage device comprises an energy module as described in the disclosure. Optionally, the energy storage device and / or its energy module has one or more features described as advantageous or optional in order to achieve an associated technical effect.

[0040] According to one aspect of the disclosure, an electrically powered motor vehicle is provided, comprising an energy storage device according to the disclosure and / or an energy module according to the disclosure. Optionally, the motor vehicle, the energy storage device, and / or its energy module have one or more features described as advantageous or optional in order to achieve an associated technical effect.

[0041] One embodiment of each is described below with reference to the figures. 24-1456

[0042] 7

[0043] Fig. 1 schematically shows a motor vehicle according to one aspect of the disclosure;

[0044] Fig. 2 schematically shows an energy module according to one aspect of the revelation;

[0045] Fig. 3 schematically shows stacks of an energy module according to one aspect of the revelation; Fig. 4 schematically shows a detail of an energy module according to one aspect of the revelation; Fig. 5 schematically shows an energy module according to one aspect of the revelation;

[0046] Fig. 6 schematically shows stacks of an energy module according to one aspect of the disclosure; and Fig. 7 schematically shows sections of an energy module according to one aspect of the disclosure.

[0047] Figure 1 schematically shows a motor vehicle 50 according to one aspect of the disclosure. The motor vehicle 50 is a land vehicle. The motor vehicle 50 is a passenger car.

[0048] The motor vehicle 50 comprises an energy storage device 55 and an electric drive 52. The energy storage device 55 has an energy module 54 with stacks 60. Each of the stacks 60 has battery cells 56, the number of which are shown only schematically. In another embodiment (not shown), the energy storage device 55 has a plurality of energy modules 54. The energy modules 54 can be identical to one another with respect to the number of stacks 60 and / or battery cells 56 and / or different in their construction. The battery cells 56 can be single cells, but also pouch cells and / or multi-layer pouch cells, comprising several single cells arranged in layers and packed together with a pouch film.

[0049] The energy storage device 55, or the battery cells 56, are configured to be supplied with electrical energy in order to charge the battery cells 56, i.e., to increase their state of charge. The energy storage device 55, or the battery cells 56, are also configured to provide electrical energy for operating the motor vehicle 50 and / or the electric drive 52, whereby the battery cells 56 are discharged, i.e., their state of charge decreases. The majority of battery cells 56 are thus configured to store and provide electrical energy.

[0050] The battery cells 56 each have a positive electrode 59a, a solid electrolyte 58, and a negative electrode 59b. The solid electrolyte 58 is configured to transport charge carriers. The battery cells 58 can have lithium ions as charge carriers and / or other metal ions as charge carriers. The solid electrolyte 58 is arranged between the positive electrode 59a and the negative electrode 59b. Thus, the solid electrolyte 58 provides a mechanical separation between the positive electrode 59a and the 24-1456

[0051] 8

[0052] The negative electrode 59b is provided, allowing charge carriers to move through the solid electrolyte 58. The positive electrode 59a, the solid electrolyte 58, and the negative electrode 59b form a layered structure 57. The positive electrode 59a, the solid electrolyte 58, and the negative electrode 59b are each stacked in layers along a stacking direction x, y, z (not shown).

[0053] Further features of the energy module 54, the stack 60 and / or the battery cells 56 are described with reference to Figures 2 to 7.

[0054] Figure 2 schematically shows an energy module 54 according to one aspect of the disclosure. The energy module 54 according to Figure 2 is an energy module 54 for an energy storage device 55 of an electrically powered motor vehicle 50. Such a motor vehicle 50 and features of such an energy module 54 are described with reference to Figure 1. Figure 2 is described with reference to Figure 1.

[0055] The energy module 54 comprises a plurality of stacks 60 (for clarity, only an upper row of stacks 60 is shown). Each stack 60 has a layered arrangement of battery cells 56 characterized by a stacking direction x, y, z (for clarity, only a portion of the battery cells 56 from two of the stacks 60 are shown). The stacking direction x, y, z is identical for all battery cells 56 in each stack 60. The battery cells 56 are stacked on top of each other according to the stacking direction x, y, z. The battery cells 56 are stacked planarly, meaning that each battery cell 56 has two large, opposing surfaces, and adjacent battery cells 56 are arranged in contact with each other at these large surfaces.

[0056] Each of the battery cells 56 has a layered structure 57 with a solid electrolyte 58. This is described and shown with reference to Figure 1. The layered structure 57 of each of the battery cells 56 within a stack 60 is oriented according to the stacking direction x, y, z. In other words, the battery cells 56 of a stack 60 and the respective stack 60 have an identical stacking direction x, y, z. The stacking direction x, y, z of the stacks 60 is schematically indicated in each of the stacks 60 by an index for the stacking direction x, y, z shown in a white circle. A coordinate system is also shown below left next to the energy module 54, which clarifies the stacking directions x, y, z.

[0057] The majority of stacks 60 are arranged side by side in such a way that a force and / or pressure from a first stack 60a of the stacks 60 is exerted on an adjacent second stack 60b of the24-1456

[0058] 9

[0059] The force can be transferred between stacks 60. For this purpose, the stacks 60 within the energy module 54 are arranged in mechanical contact with each other. Through this mechanical contact, a force can be transferred from the first stack 60a to the adjacent second stack 60b.

[0060] The first stack 60a and the second stack 60b have different stacking directions x, y. In other words, the first stack 60a has the stacking direction y and the second stack 60b has the stacking direction x. The stacking directions x, y of the first stack 60a and the second stack 60b are therefore 90° different from each other.

[0061] The stacks 60 of the energy module 54 according to Figure 2 are arranged in a plane and two-dimensionally. In other words, the different stacking directions x, y of adjacent stacks 60 mean that adjacent stacks 60 have alternating stacking directions x, y.

[0062] Each of the stacks 60 has a compensating layer 61 oriented in the same direction (x, y) on an outer surface (not indicated) of the stack 60 that is oriented in the same direction (x, y) as the stack 60. Furthermore, stacks 60, in particular stacks 60 that are not located at the edge of the energy module 54, can have two compensating layers 61. A compensating layer 61 of one of the stacks 60 contacts all battery cells 56 of an adjacent stack 60. This allows a homogeneously distributed pressure and / or a corresponding force to be transferred or exerted from one of the stacks 60 to a correspondingly adjacent stack 60.

[0063] The energy module 54 incorporates a pressure device 70. The pressure device 70 can, for example, have a plurality of pressure plates arranged around the energy module 54. A continuous pressure plate can be provided on each side of the energy module 54. The pressure device 70 is configured to exert a force and / or pressure on the stacks 60 arranged at the edge of the energy module 54 (schematically indicated by arrows). Through contact between the stacks 60, the force or pressure is propagated through the plurality of stacks 60 of the energy module 54. The pressure device 70 is configured to exert a force and / or pressure on the plurality of stacks 60.

[0064] In the two-dimensional arrangement of stacks 60 according to Figure 2, a volume 75 is provided between four adjacent stacks 60 (not indicated in Figure 2), see Figure 4.24-1456

[0065] 10

[0066] The arrangement of several stacks 60 according to Figure 2 is geometrically characterized by a unit cell. The energy module 54 has a translationally symmetric arrangement of stacks 60 according to the unit cell. For the two-dimensional arrangement of the stacks 60, two possibilities of a unit cell can be distinguished: two stacks 60 in the direction of the stacking direction x and two stacks 60 in the direction of the stacking direction y. The unit cells can be represented by a 2x2 matrix, where the entries of the matrix index the stacking direction x, y of a stack 60 arranged in the unit cell according to the index of the matrix: [x, y; y, x] and [y, x; x, y], where a divider separates the rows of the matrix and a divider separates the entries of the matrix within a row. When considering the stacking direction, the arrangement according to the unit cell describes an exclusive singulation criterion.

[0067] The stacks 60 have at least partially different numbers of battery cells 56. For example, the stack 60 located at the coordinate (x=4, y=2) has fewer battery cells 56 and thus a smaller thickness (in the x-direction) than the stack 60 located at the coordinate (x=4, y=1). This results in the free volume 75. Taking into account the number of battery cells 56, the elementary time described above can be extended to a 4x4 matrix.

[0068] Figure 3 schematically shows stacks 60 of an energy module 54 according to one aspect of the revelation. Figure 3 shows a section or side view of the energy module 54 according to Figure 2. Figure 3 is described with reference to Figures 1 and 2. Figure 3 illustrates the alternating arrangement of the stacks 60, which extends across the energy module 54 in rows and columns.

[0069] Figure 4 schematically shows a detail of an energy module 54 according to an aspect of the revelation. Figure 4 depicts the energy module 54 as shown in Figures 2 and 3. Figure 4 is described with reference to Figures 1 to 3.

[0070] The detail shown in Figure 4 is indicated in Figures 4 and 2 by a circle with a dotted line. This illustrates, in particular, how the compensating surfaces 61 of four adjacent stacks 60 abut each other. A volume 75 is formed between the stacks 60, and especially between the compensating surfaces 61. The size of the volume 75 is determined by an overlap dx in the stacking direction x of a first stack 60a and an adjacent second stack 60b, and an overlap dy in the stacking direction y of a first stack 60a and an adjacent second stack 60b. The overlap dx, dy, and thus the size of the volume 75, depend on the extent of all stacks 60 arranged around the volume 75 in the x and y directions from this position to the module edges or printing plates 70.The volume 75 can increase when the stacks of 60 shrink and decrease when the stacks of 60 expand.

[0071] Figure 5 schematically shows an energy module 54 according to one aspect of the disclosure. The energy module 54 according to Figure 5 is a different or alternative embodiment compared to the energy module 54 according to Figures 2 to 4. Figure 5 is described with reference to Figures 2 to 4, and the differences of the energy module 54 are described.

[0072] In Figure 5, the battery cells 56 and the equalization layers 61 are hidden.

[0073] The stacks 60 are arranged spatially and three-dimensionally. This results in an arrangement of stacks 60 in three different stacking directions x, y, z. The stacks 60 thus form rows, columns, and columns. The rows of the energy module 54 can also be referred to as levels I, II, III. The energy module 54 according to Figure 5 has, by way of example, a first level I, a second level II, and a third level III. Adjacent stacks 60 have a non-constant sequence of stacking directions x, y, z; and within a row, a column, and a column, stacks 60 with all stacking directions x, y, z are provided, as described with reference to Figures 6 and 7.

[0074] Figure 6 schematically shows stacks 60 of an energy module 54 according to one aspect of the revelation. The stacks 60 in Figure 6 illustrate the orientations of the stacks 60 of the energy module 54 according to Figure 5. Figure 6 is described with reference to Figures 1 to 5.

[0075] In Figure 6, the battery cells 56 are schematically indicated. Possible leveling layers 71 are hidden. Figure 6 is divided into three sections (A), (B), (C), each of which has a stack 60 with an index for the stack direction x, y, z listed in a white circle.

[0076] Figure 7 schematically shows sections of an energy module 54 according to one aspect of the revelation. The sections of energy module 54 illustrate the energy module 54 according to Figures 5 and 6. Figure 7 is described with reference to Figures 1 to 6.12

[0077] In Figure 1, the battery cells 56 and the balancing layers 61 are hidden.

[0078] Figure 7 is divided into three sections (A), (B), (C), each showing one of the levels I, II, III of the energy module 54 according to Figure 5. The stacks 60 have a stacking direction x, y, z, with an index for the stacking direction x, y, z indicated by a white circle. Due to the three-dimensional arrangement of the stacks 60, the energy module 54 has, in addition to first stacks 60a and second stacks 60b, third stacks 60c. Adjacent stacks 60 also have different stacking directions x, y, z, which are perpendicular to each other or form a 90° angle with each other.

[0079] In the three-dimensional arrangement of stacks 60, a volume 75 is provided between eight adjacent stacks 60, as well as between four adjacent stacks 60 (not shown), comparable to a two-dimensional arrangement in which an elongated cuboid volume 75 is provided.

[0080] In the case of the 3D arrangement of the stacks, the matrix notation described with reference to Figure 2 is extended by another dimension, and the unit cell is a 3x3x3 matrix—both with respect to the stacking direction x, y, z. One possible form of the matrix is ​​[[x, y, z; z, x, y; y, z, x], [z, x, y; y, z, x; x, y, z], [y, z, x; x, y, z; z, x, y]]. Furthermore, other corresponding permutations exist. With the exclusive singulation criterion "stack direction," the unit cell is a 3x3x3 matrix. With "number of cells per stack," the unit cell matrix can be larger.

[0081] As a configuration for energy modules 54, multiples in the x and y directions (2D arrangement) or in the x, y, and z directions (3D arrangement) of the respective elementary arrangements of stacks 60 are conceivable. The outer dimensions of a battery cell 56, which, for example, has a cuboid shape, define the dimensions of the respective stacks 60, but do not necessarily have to consist of cuboids with two sides of equal length, as shown in the figures.13

[0082] Reference symbol (part of the description)

[0083] 50 motor vehicles

[0084] 52 electric drive

[0085] 54 Energy module

[0086] 55 Energy storage device

[0087] 56 battery cells

[0088] 57 Layer structure

[0089] 58 Solid-state electrolytes

[0090] 59a positive electrode

[0091] 59b negative electrode

[0092] 60 stacks

[0093] 60a first stack

[0094] 60b second pile

[0095] 60c third stack

[0096] 61 Leveling layer

[0097] 70 Printing device

[0098] 75 volume

[0099] dx overlap

[0100] dy overlap

[0101] I first level

[0102] II second level

[0103] III third level

[0104] x Stacking direction

[0105] y Stacking direction

[0106] z Stacking direction

Claims

24-1456 14 Claims 1. Energy module (54) for an energy storage device (55) of an electrically powered motor vehicle (50), wherein - the energy module (54) has a plurality of stacks (60); - each of the stacks (60) has a layered arrangement of battery cells (56) characterized by a stacking direction (x, y, z); -each of the battery cells (56) has a layered structure (57) with a solid electrolyte (58); - the layer structure (57) of each of the battery cells (56) within a stack (60) is oriented according to the stack direction (x, y, z); and - the majority of stacks (60) are arranged such that a force and / or pressure can be transferred from a first stack (60a) of the stacks (60) to an adjacent second stack (60b) of the stacks (60) and the first stack (60a) and the second stack (60b) have different stacking directions (x, y, z) from each other.

2. Energy module (54) according to claim 1, wherein - each of the stacks (60) has a leveling layer (61) oriented in accordance with the stacking direction (x, y, z) of the stack (60) on an outer surface of the stack (60) oriented in accordance with the stacking direction (x, y, z).

3. Energy module (54) according to claim 1 or 2, wherein - the energy module (54) has a pressure device (70); wherein - the pressure device (70) is configured to apply a force and / or pressure to the majority of the stacks (60).

4. Energy module (54) according to one of the preceding claims, wherein - the stacks (60) are arranged in a plane and / or two-dimensionally; and - adjacent stacks (60) have alternating stacking directions (x, y).

5. Energy module (54) according to one of the preceding claims, wherein - the stacks (60) are arranged spatially and / or three-dimensionally; - adjacent stacks (60) exhibit a non-constant sequence of stacking directions (x, y, z); and24-1456 15 - within each row, column and line, stacks (60) are provided with all stacking directions (x, y, z).

6. Energy module (54) according to one of the preceding claims, wherein - the arrangement of several of the stacks (60) is geometrically characterized by a unit cell; and - the energy module (54) has a translationally symmetric arrangement of stacks (60) according to the unit cell.

7. Energy module (54) according to one of the preceding claims, wherein - the stacks (60) have at least partially different numbers of battery cells (56).

8. Energy module (54) according to one of the preceding claims, wherein - in a two-dimensional arrangement of stacks (60) a volume (75) is provided between four adjacent stacks (60); and / or - in a three-dimensional arrangement of stacks (60) a volume (75) is provided between eight adjacent stacks (60).

9. Energy storage device (55) for an electrically powered motor vehicle (50), wherein the energy storage device (55) comprises an energy module (54) according to one of the preceding claims.

10. Electrically powered motor vehicle (50) comprising an energy storage device (55) according to claim 9 and / or an energy module (54) according to any one of claims 1 to 8.

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