Electrical energy storage device, device and / or vehicle and method for producing an electrical energy storage device

Abstract

An electrical energy accumulator, a device and / or a vehicle and a method for producing an electrical energy accumulator. An electrical energy accumulator (1), a device and / or a vehicle and a method for producing an electrical energy accumulator (1) having a control unit (11) and electrical energy storage cells (2), each of which has a battery control device (31), wherein the control unit (11) has a printed circuit board which is connected to the corresponding battery control device (31) of each electrical energy storage cell (2) in a material-locking manner.

Description

Technical Field

[0001] The invention relates to an electrical energy storage device, a device and / or a vehicle and a method for producing an electrical energy storage device according to the preambles of the independent patent claims. Background Art

[0002] EP 3 142 165 A1 shows a battery system with overcharge and / or deep discharge protection, which has a rapid discharge unit and a trigger unit having an electrically conductive mechanical component for triggering the rapid discharge unit.

[0003] EP 3 142 172 A1 shows a battery system with overcharge and / or deep discharge protection. The battery system comprises: a fast discharge unit for quickly discharging an electric energy storage device, the electric energy storage device having a first connection terminal electrically connected to a first pole of the battery, the electric energy storage device having a second connection terminal electrically connected to a second pole of the battery; and a trigger unit for triggering the fast discharge unit.

[0004] EP 3 128 575 A1 shows a rechargeable battery with a charging and discharging unit arranged above the battery. Summary of the invention

[0005] The core of the invention with respect to an electrical energy storage device having a control unit and electrical energy storage cells, each of which has a battery control unit, is that the control unit has a printed circuit board which is integrally connected to the respective battery control unit of each electrical energy storage cell.

[0006] The invention is based on the fact that the electrical energy storage device can be designed compactly and lightly. A printed circuit board of the battery control device and a printed circuit board component are connected in a cohesive manner, in particular wherein conductor tracks of the printed circuit board are electrically conductively connected to other conductor tracks of the printed circuit board component.

[0007] Advantageously, the energy density of the electrical energy storage device is improved.

[0008] Further advantageous embodiments of the invention are the subject of the following description.

[0009] According to an advantageous embodiment, the printed circuit board has a first cutout and a conductor track, wherein the corresponding conductor track is connected to the corresponding contact surface of the battery control device through the first cutout by material fit, in particular by welding, in particular by means of laser welding. As a result, the conductor track can be reliably connected to the contact surface. Compared to, for example, a soldering process, the energy input into the electrical energy storage cell can be reduced by using laser welding. As a result, the printed circuit board can be connected to the battery control device connected to the electrical energy storage cell without the electrical energy storage cell reaching a critical temperature for the electrical energy storage cell.

[0010] It is advantageous here if the printed circuit board has a control circuit which is connected to the battery control device by means of conductor tracks and contact surfaces. The electrical energy storage device can thus be designed in a compact manner.

[0011] It is also advantageous if the control unit has a housing part, wherein the housing part has a third recess, wherein the third recess covers each first recess. The housing part at least partially forms a housing around the control unit. Through the respective third recess, a material connection of the printed circuit board to the respective battery control unit can be established. Thus, the electrical energy storage device can first be installed before the printed circuit board is materially connected to the respective battery control unit.

[0012] Advantageously, the third recess is sealed by means of a transparent film, in particular a laser-transparent film. Here, the film is transparent to the laser beam used for laser welding. The film also seals the third recess in a liquid-tight manner.

[0013] According to an advantageous embodiment, the printed circuit board is connected to each electrical energy storage cell in a form-fitting manner. The form-fitting connection allows the printed circuit board and the electrical energy storage cell to be oriented relative to one another. Advantageously, the printed circuit board and the electrical energy storage cell are first connected to one another in a form-fitting manner and then in a materially bonded manner. As a result, the corresponding connection surfaces between the printed circuit board and the respective electrical energy storage cell can be positioned with high precision before the materially bonded connection is established.

[0014] It is advantageous if each electrical storage cell has at least one projection which is guided through a respective second cutout in the printed circuit board. The printed circuit board and the respective electrical storage cell can thus be easily aligned relative to one another by means of the projection and the second cutout.

[0015] It is also advantageous if the projections of the electrical storage cells are arranged in alignment and the second cutouts in the printed circuit board are arranged in alignment. As a result, the electrical storage cells can be easily oriented relative to one another, in particular with the aid of a mounting device.

[0016] According to another advantageous embodiment, each electrical energy storage cell has a discharge device which can be controlled by means of the battery control device. Advantageously, the electrical energy storage cell can be discharged by means of the discharge device in critical operating states. This makes it possible to establish a safe state of the electrical energy storage cell. Advantageously, the electrical energy storage device can continue to be used after the electrical energy storage cell has been discharged.

[0017] The core of the invention with regard to a device and / or a vehicle is that the device and / or the vehicle has at least one electrical energy storage device as described above.

[0018] The background of the invention is that the electrical energy storage device can be designed compactly and lightly. As a result, the energy density of the electrical energy storage device is improved. The electrical energy storage device can be designed smaller and / or lighter. As a result, the mass of the device and / or the vehicle can be reduced and / or the range of the vehicle can be increased.

[0019] The core of the invention with respect to a method for producing an electrical energy storage device, in particular an electrical energy storage device as described above, is that the method has the following method steps which are sequential in time:

[0020] wherein in a first method step, the electrical energy storage cells of the electrical energy storage device are arranged next to one another;

[0021] wherein in a second method step, the electrical energy storage cells are connected to one another, in particular fastened to one another;

[0022] wherein in a third method step, cell connectors are arranged on the electrical energy storage cells and connected to cell terminals of the electrical energy storage cells;

[0023] wherein in a fourth method step, a control unit is oriented relative to the electrical energy storage cells and connected to the electrical energy storage cells;

[0024] In a fifth method step, the control circuit of the control unit is connected to the battery control unit in a signal-conducting and / or electrically conductive manner, in particular by means of laser welding.

[0025] The background of the invention is that the electrical energy storage devices are arranged, oriented and connected to one another and to a control unit before the control circuit is connected to the battery control device in a signal-conducting manner. As a result, a reliable signal-conducting connection of the control circuit to the battery control device can be achieved, since the components of the electrical energy storage devices are fixed relative to one another. The control circuit and the battery control device can be connected in a signal-conducting manner at points.

[0026] Advantageously, laser welding is used to produce the signal-conducting connection, whereby the energy input into the electrical energy storage cell can be reduced compared to, for example, soldering processes. Thus, the printed circuit board can be connected to a battery control unit connected to the electrical energy storage cell without the electrical energy storage cell reaching temperatures that are critical for these electrical energy storage cells.

[0027] According to an advantageous embodiment, in a first method step, the electrical energy storage cells are arranged such that the positive and negative electrical connections of the respective energy storage cells are arranged alternately. It is advantageous here that, in the case of a series connection of the electrical energy storage cells, the cell connector can be designed compactly for connecting the positive and negative electrical connections of adjacent electrical energy storage cells.

[0028] Advantageously, the electrical energy storage cells are oriented such that the projections on the electrical energy storage cells are oriented in alignment. As a result, the electrical energy storage cells can be oriented relative to one another in a simple manner, in particular by means of a mounting aid.

[0029] The above-mentioned designs and extensions can be combined with each other arbitrarily as long as they are reasonable. Other possible designs, extensions and implementations of the present invention also include combinations of features not explicitly mentioned before or after the present invention are described in relation to the embodiments. In this regard, those skilled in the art will also add individual aspects as improvements or supplements to the corresponding basic form of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In the following paragraphs, the invention is explained based on embodiments from which other inventive features can be derived, but to which the invention is not limited within its scope of protection. These embodiments are shown in the accompanying drawings.

[0031] in:

[0032] Figure 1 An exploded view of an electrical energy storage device 1 according to the invention is shown;

[0033] Figure 2 Shown in Figure 1 A perspective side view of an electrical energy storage device 1 according to the invention is shown in FIG.

[0034] Figure 3 Shown in Figure 1 A detailed view of an electrical energy storage device 1 according to the invention is shown in FIG.

[0035] Figure 4 A flow chart of a method according to the invention for producing an electrical energy storage device 1 is shown. DETAILED DESCRIPTION

[0036] exist Figure 1 The electrical energy storage device 1 according to the invention shown in FIG. 1 has:

[0037] - at least two electrical energy storage batteries 2,

[0038] - at least one cell connector 13 for electrically conductively connecting the electrical energy storage cell 2,

[0039] - Top cover 14,

[0040] - fastening means 12,

[0041] - a control unit 11, and

[0042] - Cooling equipment 6.

[0043] The electrical energy storage cells 2 are embodied in a cuboid shape and each have six side faces. The electrical energy storage cells 2 are arranged stacked in the electrical energy storage device 1. In this case, two electrical energy storage cells 2 are each contacted by means of the largest side face of the respective energy storage cell 2.

[0044] The electrical energy storage cell 2 is fastened by means of a cover part 14 and a fastening device 12. Here, the cover part 14 and the fastening device 12 extend along a stacking direction 17 of the electrical energy storage device 1. The cover part 14 and the fastening device 12 are arranged opposite one another. The electrical energy storage cell 2 is arranged between the cover part 14 and the fastening device 12, in particular clamped by means of the cover part 14 and the fastening device 12.

[0045] Preferably, the cover part 14 and / or the fastening device 12 are designed as sheet metal parts, in particular as stamped and bent parts.

[0046] The cover element 14 has a cover part 18 and two first cover element side parts 20 and two second cover element side parts 19, wherein the first and second cover element side parts (19, 20) protrude from the cover part 18. Preferably, the first or second cover element side parts (20, 19) and the cover part 18 each enclose an angle, wherein the angle is between 60° and 120°, in particular wherein the angle is a right angle. The cover part 18 completely covers the side of each electrical energy storage cell 2.

[0047] The first cover part side parts 20 are arranged opposite one another on the cover part 18. The first cover part side parts 20 each partially cover the largest side of the outer electrical energy storage cells 2 of the electrical energy storage device 1, preferably to 20% to 50%.

[0048] The second cover part side parts 19 are arranged opposite one another on the cover part 18. The second cover part side parts 19 each partially cover the other side of each electrical energy storage cell 2 of the electrical energy storage device 1, preferably to 5% to 20%.

[0049] The fastening devices 12 extend along the other side surfaces of the electrical energy storage cells 2 and in each case partially cover the other side surfaces of the electrical energy storage cells 2 , preferably to 5% to 20%.

[0050] At least one cooling device 6 is arranged adjacent to the energy storage cell 2, preferably one cooling device 6 is arranged in each case next to the energy storage cell 2 on the outside of the energy storage device 1 in the stacking direction 17. The cooling device 6 is preferably designed as a ventilator.

[0051] The electrical energy storage cells 2 can be connected to one another in an electrically conductive manner by means of cell connectors 13. For this purpose, the cell connectors 13 are arranged on other sides of the electrical energy storage cells 2.

[0052] The control unit 11 is at least partially arranged in the housing element 22. The control unit 11 extends along other sides of the electrical energy storage cell 2. Between the control unit 11 and the electrical energy storage cell 2 a cell connector 13 is arranged.

[0053] The electrical energy storage cell 2 has:

[0054] - a housing 16 in which the electrodes, the separator and the electrolyte of the electrical energy storage cell 2 are arranged,

[0055] - discharge device 15,

[0056] - a battery control device 31, which has a discharge control device,

[0057] - safety valve,

[0058] - at least one battery terminal 7 for contacting the electrode, and

[0059] An insulation system having a first insulation device 3 , a second insulation device 8 , a third insulation device 5 , a fourth insulation device 10 , a fifth insulation device 4 and a sixth insulation device 9 .

[0060] The housing 16 is designed as a metal housing and surrounds the electrodes, the separator and the electrolyte in a housing-like manner. The battery terminals 7 and the battery control unit 31 are arranged on a third side of the housing 16 .

[0061] The housing 16 is preferably electrically conductively connected to the electrodes of the electrical energy storage cell 2 and serves as a further cell terminal.

[0062] The housing 16 is completely surrounded by the insulation system, the battery terminal 7, the battery control device 31 and the discharge device 15. The first insulation device 3 and the second insulation device 8 each have two side parts and a base part, and the first and second insulation devices (3, 8) are preferably implemented in a U shape. The housing 16 is arranged between the two side parts of each first and second insulation device (3, 8). Here, the side parts of the first and second insulation devices (3, 8) overlap.

[0063] The first side, especially the largest side, of the housing 16 is covered, especially completely covered, by the side portions of the first insulating device 3 and the second insulating device 8. Preferably, the side portions of the first insulating device 3 completely cover the side portions of the second insulating device 8.

[0064] The side parts of the first insulating device 3 and the side parts of the second insulating device 8 are covered by means of the third insulating device 5 .

[0065] Another side portion of the first insulating device 3 and another side portion of the second insulating device 8 are covered by means of a fourth insulating device 10 .

[0066] The third insulating device 5 and the fourth insulating device 10 are each designed to be plate-shaped and / or flat.

[0067] The first and / or second and / or third and / or fourth insulation device (3, 8, 5, 10) is embodied as a molded part and / or from a film, in particular from plastic.

[0068] The sixth insulating device 9 is arranged on a third side of the housing 16. For this purpose, the sixth insulating device 9 has a recess having the shape of the outer shape of the battery terminal 7, the battery control unit 31 and the discharge device 15.

[0069] The electrical energy storage cells 2 of the electrical energy storage device 1 and the insulation systems of the further electrical energy storage cells 2 are arranged in the stacking direction 17 in the following stacking sequence:

[0070] - a third insulating device 5 of the electrical energy storage cell 2,

[0071] - a first insulating device 3 of the electrical energy storage cell 2,

[0072] - a second insulating device 8 of the electrical energy storage cell 2,

[0073] - the housing 16 of the electrical energy storage cell 2,

[0074] - a second insulating device 8 of the electrical energy storage cell 2,

[0075] - a first insulating device 3 of the electrical energy storage cell 2,

[0076] - a fourth insulating device 10 of the electrical energy storage cell 2,

[0077] - a third insulating device 5 of the further electrical energy storage cell 2,

[0078] - a first insulating device 3 of the further electrical energy storage cell 2,

[0079] - a second insulating device 8 of the further electrical energy storage cell 2,

[0080] - the housing 16 of the further electrical energy storage cell 2,

[0081] - a second insulating device 8 of the further electrical energy storage cell 2,

[0082] - a first insulating device 3 of the further electrical energy storage cell 2,

[0083] A fourth insulation device 10 of the further electrical energy storage cell 2 .

[0084] In this case, the order of the first and second insulating devices (3, 8) can be interchanged in each case.

[0085] Instead of the fourth insulation device 10 of the electrical energy storage cell 2 and the third insulation device 5 of the further electrical energy storage cell 2 , a single insulation device can be arranged between the first insulation device 3 of the electrical energy storage cell 2 and the first insulation device 3 of the further electrical energy storage cell 2 .

[0086] The housing 16 has a safety valve. The safety valve is arranged on the second side of the housing 16, in particular, opposite to the battery terminal 7, the battery control device 31 and the discharge device 15. The safety valve is at least partially covered by the fifth insulating device 4. Preferably, the fifth insulating device 4 has a recess in the area of ​​the safety valve. That is, the fifth insulating device 4 is arranged on the side of the housing 16 opposite to the sixth insulating device 9.

[0087] The fifth and sixth insulating means (4, 9) are designed as cast parts, in particular as plastic cast parts.

[0088] Preferably, the insulating means (3, 8, 5, 10, 4, 9) are adhesively bonded to the electrical energy storage cell 2, in particular wherein the insulating means (3, 8, 5, 10, 4, 9) each comprise an adhesive. Preferably, the first and / or second and / or third and / or fourth insulating means (3, 8, 5, 10) are designed as adhesive films.

[0089] exist Figure 2 , an electrical energy storage device 1 is shown in a side view.

[0090] The cell connectors 13 each connect a cell terminal 7 of an electrical energy storage cell 2 to a housing 16 of an adjacent electrical energy storage cell 2. The electrical energy storage cells 2 are preferably arranged in series by means of the cell connectors 13.

[0091] In this case, the cell terminals 7 are first electrical connections of the electrical storage cells 2 and the housing 16 serves as a second electrical connection of the electrical storage cells 2. The respective cell terminals 7 are arranged electrically insulated from the respective housing 16 of the respective electrical storage cells 2.

[0092] The housing 16 of the electrical energy storage cell 2 on the outside in the stacking direction 17 is electrically conductively connected to a connection device 30 for electrically conductively connecting the electrical energy storage cell 2 to a connection device 40 of the electrical energy storage device 1. The connection device 30 is designed as a sheet metal part, in particular as a stamped and bent part. For example, the connection device 40 is designed as a screw part, in particular as a screw.

[0093] The discharge device 15 is connected to a battery control device 31, which has a discharge control device for controlling the discharge device 15. Alternatively or additionally, the battery control device 31 is connected to at least one sensor for determining an operating parameter of the electrical energy storage cell 2, in particular the battery control device 31 is designed to determine an operating state of the electrical energy storage cell 2.

[0094] The battery control unit 31 is embodied as an integrated circuit, for example, on a printed circuit board component.

[0095] Each electrical energy storage cell 2 has a separate discharge device 15 and a separate cell control unit 31 .

[0096] The respective electrical energy storage cell 2 can be discharged in a controlled manner by means of the discharge device 15. For this purpose, the discharge device 15 is respectively connected in an electrically conductive manner to the cell terminals 7 and the housing 16 of the respective electrical energy storage cell 2.

[0097] The electrical energy storage cell 2, in particular the discharge device 15, has a projection 41 for connecting the electrical energy storage cell 2 to the control unit 11. The respective projection 41 projects from the electrical energy storage cell 2, in particular from the discharge device 15, and is designed, for example, as a pin.

[0098] The electrical energy storage cells 2 are arranged in the electrical energy storage device 1 such that all projections 41 are arranged in alignment.

[0099] The battery control unit 31 has at least one contact surface 43 which is arranged on a printed circuit board component. The battery control unit 31 can be connected to the control unit 11 in a signal-conducting manner by means of the contact surface 43 .

[0100] exist Figure 31 shows an electrical energy storage device 1 with a control unit 11. Here, the housing part 22 of the control unit 11 is concealed, so that a printed circuit board 42 is visible, on which a control circuit 44, in particular a microcontroller, is arranged. Preferably, the printed circuit board 42 is designed as a flexible printed circuit board.

[0101] The printed circuit board 42 has conductor tracks 45 for electrically conductively connecting the control circuit 44 to the battery control unit 31. The printed circuit board 42 has a first recess 46 and a second recess 47 which are each spaced apart from one another.

[0102] By means of the second recesses 47 the printed circuit board 42 can be aligned relative to the electrical energy storage cell 2 , in particular relative to the discharge device 15 and / or relative to the battery control unit 31 . To this end, the respective projection 41 is at least partially guided through the respective second recess 47 .

[0103] By means of the respective first recess 46 , the respective conductor track 45 can be connected to the respective contact surface 43 of the respective battery control unit 31 , in particular by means of laser welding.

[0104] The housing part 22 of the control unit 11 has third cutouts 21 spaced apart from one another. When the housing part 22 is mounted on the control unit 11, the corresponding conductor tracks 45 are connected to the corresponding contact surfaces 43 by means of the third cutouts 21. For this purpose, the third cutouts 21 are preferably covered with a laser-transparent material, in particular a laser-transparent film. The third cutouts 21 are arranged in an aligned manner.

[0105] exist Figure 4 Detailed Description of the Invention A flow chart of a method 100 according to the invention for producing an electrical energy storage device 1 is shown in FIG.

[0106] The method 100 has the following method steps which are sequential in time:

[0107] In a first method step 101 , the electrical storage cells 2 are arranged next to each other, wherein the positive and negative electrical connections of the respective storage cells 2 are arranged alternately. In this case, the electrical storage cells 2 are oriented such that all projections 41 are aligned.

[0108] In a second method step 102 , the electrical energy storage cells 2 are connected to one another, in particular fixed to one another, by means of the cover part 14 and the fastening device 12 .

[0109] In a third method step 103 , the cell connector 13 is arranged on the electrical energy storage cell 2 and connected to the cell terminals 7 .

[0110] In a fourth method step 104 , the control unit 11 is aligned relative to the electrical energy storage cell 2 and connected to the electrical energy storage cell 1 .

[0111] In a fifth method step 105 , the control circuit 44 of the control unit 11 is connected to the battery control unit 31 in a signal-conducting and / or electrically conductive manner, in particular by means of laser welding.

[0112] In this case, an electrical energy storage device is understood to be a rechargeable energy storage device which has, in particular, an electrochemical energy storage cell and / or an energy storage module having at least one electrochemical energy storage cell and / or an energy storage pack having at least one energy storage module. The energy storage cell can be designed as a lithium-based battery cell, in particular a lithium-ion battery cell. Alternatively, the energy storage cell is designed as a lithium polymer battery cell or a nickel metal hydride battery cell or a lead-acid battery cell or a lithium-air battery cell or a lithium-sulfur battery cell.

Claims

1. An electrical energy storage device (1), comprising a control unit (11) and electrical energy storage cells (2), each of which has a battery control device (31), It is characterized in that The control unit (11) has a printed circuit board (42) which is materially connected to a corresponding battery control unit (31) of each electrical energy storage cell (2). The printed circuit board (42) comprises a first cutout (46) and a conductor track (45), wherein the corresponding conductor track (45) passes through the first cutout (46) and is connected to the corresponding contact surface (43) of the battery control unit (31) in a materially bonded manner. The control unit (11) has a housing part (22), wherein the housing part (22) has third recesses (21), wherein the third recesses (21) respectively cover the first recesses (46).

2. The electrical energy storage device (1) according to claim 1, It is characterized in that The corresponding conductor tracks (45) are connected to the corresponding contact surfaces (43) of the battery control unit (31) by welding through the first recess (46).

3. The electrical energy storage device (1) according to claim 2, It is characterized in that The corresponding conductor tracks (45) are connected through the first cutouts (46) to the corresponding contact surfaces (43) of the battery control unit (31) by means of laser welding.

4. The electrical energy storage device (1) according to claim 2, It is characterized in that The printed circuit board (42) has a control circuit (44) which is connected to the battery control unit (31) by means of the conductor tracks (45) and the contact surfaces (43).

5. The electrical energy storage device (1) according to any one of claims 2 to 4, It is characterized in that The third recess (21) is sealed by means of a transparent film.

6. The electrical energy storage device (1) according to claim 5, It is characterized in that The third recess (21) is sealed by means of a laser-transparent film.

7. The electrical energy storage device (1) according to any one of claims 1 to 4, It is characterized in that The printed circuit board (42) is connected in a form-fitting manner to each electrical energy storage cell (2).

8. The electrical energy storage device (1) according to claim 7, It is characterized in that Each electrical energy storage cell (2) has at least one projection (41) which is respectively guided through a corresponding second recess (47) in the printed circuit board (42).

9. The electrical energy storage device (1) according to claim 8, It is characterized in that The printed circuit board (42) can be aligned by means of the projection (41) and the second recess (47).

10. The electrical energy storage device (1) according to claim 8, It is characterized in that The projections (41) of the electrical energy storage cells (2) are arranged in an aligned manner, and the second recesses (47) in the printed circuit board (42) are arranged in an aligned manner.

11. The electrical energy storage device (1) according to any one of claims 1 to 4, It is characterized in that Each electrical energy storage cell (2) has a discharge device (15) which can be controlled by means of the battery control unit (31). 12 . A device and / or a vehicle having at least one electrical energy storage device ( 1 ) according to claim 1 .

13. A method (100) for producing an electrical energy storage device (1) according to claim 1, comprising the following method steps which are sequential in time: wherein in a first method step (101), the electrical energy storage cells (2) of the electrical energy storage device (1) are arranged next to one another; wherein in a second method step (102), the electrical energy storage cells (2) are connected to one another; wherein in a third method step (103), a cell connector (13) is arranged on the electrical energy storage cell (2) and connected to a cell terminal (7) of the electrical energy storage cell (2); wherein in a fourth method step (104), a control unit (11) is oriented relative to the electrical energy storage cell (2) and connected to the electrical energy storage device (1); In a fifth method step (105), the control circuit (44) of the control unit (11) is connected to the battery control unit (31) in a signal-conducting and / or electrically conductive manner.

14. The method according to claim 13, It is characterized in that In a second method step (102), the electrical energy storage cells (2) are fastened to one another.

15. The method according to claim 13, It is characterized in that In a fifth method step (105), the control circuit (44) of the control unit (11) and the battery control unit (31) are connected by means of laser welding.

16. The method according to any one of claims 13 to 15, It is characterized in that In a first method step (101), the electrical energy storage cells (2) are arranged in such a way that the positive and negative electrical connections of the respective energy storage cells (2) are arranged alternately.

17. The method according to claim 16, It is characterized in that The electrical energy storage cells (2) are oriented such that the projections (41) on the electrical energy storage cells (2) are oriented in an aligned manner.

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