BATTERY CELL MODULE, POSITIONING DEVICE FOR THE PRODUCTION OF BATTERY CELL MODULES, AND METHOD FOR THE PRODUCTION OF BATTERY CELL MODULES

Abstract

Battery cell module for electrically operated vehicles, which has a plurality of elongated, in particular cylindrical, battery cells whose longitudinal axes are aligned parallel to one another, the battery cells being arranged in such a way that a first row of battery cells runs parallel to a second row of battery cells, so that in each case two battery cells are arranged opposite one another in pairs, the respectively opposite battery cells being electrically and mechanically rigidly connected to one another by means of at least one contact sheet in each case. In each case adjacent contact sheets are rigidly connected to one another electrically and mechanically by means of at least one contact sheet connector in each case.

Claims

1. A battery cell module for electrically operated vehicles, comprising a plurality of elongated, in particular cylindrical, battery cells whose longitudinal axes are aligned parallel to one another, the battery cells being arranged in such a way that a first row of battery cells runs parallel to a second row of battery cells, so that in each case two battery cells are arranged opposite one another in pairs, the battery cells are each positioned relative to one another such that the cylindrical surfaces of the battery cells are not in physical contact and a respective clearance is provided between the battery cells which is configured for an expected thermally induced circumferential expansion of the battery cells; the respective opposing battery cells being electrically and mechanically rigidly connected to one another by means of at least one contact sheet in each case; and wherein in each case adjacent contact sheets are electrically and mechanically rigidly connected to one another by means of in each case at least one contact sheet connector, wherein the battery cells connected to one another in each case by the at least one contact sheet are held spaced apart from one another by the respective at least one contact sheet, and wherein the battery cell pairs connected to one another in each case by the at least one contact sheet connector are held spaced apart from one another by the respective at least one contact sheet connector.

2. (canceled)

3. The battery cell module, according to claim 1, wherein adjacent battery cell pairs are offset from each other such that the first and second rows of battery cells are parallel in a zigzag shape.

4. The battery cell module according to claim 3, wherein the zigzag shape is selected such that the longitudinal axes of all respectively adjacent battery cells have the same distance from each other.

5. The battery cell module according to claim 1, wherein the battery cells have contact surfaces spaced apart from one another along their longitudinal axes on their upper sides and their lower sides in each case, wherein the at least one contact sheet of the battery cells connected by means of contact sheets is fastened, in particular welded, to the respective contact surfaces of the connected battery cells on both upper sides and/or on both lower sides in each case.

6. The battery cell module according to claim 1, wherein the at least one contact sheet connector is formed integrally with the contact sheets connected thereto and adjacent to one another.

7. The battery cell module according to claim 1, wherein the at least one contact sheet has two contact sections and a central web connecting the contact sections, wherein the contact sections are rounded at the ends.

8. A positioning device for the production of battery cell modules for electrically powered vehicles according to claim 1, having a carrier element for holding a plurality of positioning elements, at least one of the positioning elements having at least one battery cell receptacle pointing away from the carrier element, and at least one positioning arm which is connected to the carrier element by its side facing away from the battery cell receptacle, the at least one battery cell receptacle being designed to receive and/or fix an outer circumferential section of an elongate, in particular cylindrical, battery cell.

9. The positioning device of claim 8, wherein the plurality of positioning elements are spaced side-by-side on the support member, the positioning arms of adjacent positioning elements having a length difference such that the battery cell receptacles face different distances away from the support member.

10. The positioning device according to claim 8, wherein the battery cell receptacles of the plurality of positioning elements are arranged with respect to each other such that the longitudinal axes of fixed battery cells are parallel to each other and the battery cells can be aligned with their outer surfaces not in contact with each other, so that a free space can be formed between adjacent battery cells, respectively.

11. The positioning device according to claim 8, wherein the battery cell holder comprises at least one of a vacuum gripper and an electromagnetic gripper.

12. A method of manufacturing battery cell modules for electrically powered vehicles, comprising: Adjacent and spaced apart pickup of at least two battery cells with a first positioning device; Adjacent and spaced picking of at least two battery cells with a second positioning device; Moving the first and second positioning devices such that the battery cells received by the first positioning device are brought into a spaced, opposite position to the battery cells received by the second positioning device with respect to each other; Welding in each case a first battery cell received by the first positioning device to in each case a second battery cell opposite the first battery cell and received by the second positioning device by means of in each case at least one contact sheet to form in each case a battery cell pair, the at least two adjacent contact sheets being formed integrally with a contact sheet connector connecting the contact sheets.

13. The method according to claim 12, further comprising: using two positioning devices for the production of battery cell modules for electrically powered vehicles, each of the two positioning devices having a carrier element for holding a plurality of positioning elements, at least one of the positioning elements having at least one battery cell receptacle pointing away from the carrier element, and at least one positioning arm which is connected to the carrier element by its side facing away from the battery cell receptacle, the at least one battery cell receptacle being designed to receive and/or fix an outer circumferential section of an elongate, in particular cylindrical, battery cell; wherein the positioning arms of both positioning devices are formed complementary to each other, so that opposing positioning arms have the same length difference as adjacent positioning arms.

14. The method of claim 12, wherein neither the battery cells respectively received in the first and second positioning devices nor the respectively opposing battery cells of a battery cell pair are in contact with their outer surfaces, so that a free space is formed between adjacent battery cells respectively.

15. The method of claim 12, wherein welding the battery cells by means of at least one contact sheet in each case to form a battery cell pair in each case comprises: welding the at least one contact sheet to the battery cell upper side of the first and the second battery cell, respectively, and/or welding the at least one contact sheet to the battery cell lower side of the first and the second battery cell, respectively.

Description

DRAWINGS

[0043] The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

[0044] Further features, advantages and characteristics of the invention can be seen in the following description of preferred embodiments of the invention with reference to the accompanying drawings, in which show:

[0045] FIG. 1 a perspective view of a top side of a battery cell module with cylindrical battery cells connected to each other via contact sheets and contact sheet connectors;

[0046] FIG. 2 a perspective view of a bottom side of a battery cell module with cylindrical battery cells connected to each other via contact sheets and contact sheet connectors;

[0047] FIG. 3 a top view of a battery cell module with spaced battery cells;

[0048] FIG. 4 a perspective view of a one-piece cell connector consisting of contact sheets and contact sheet connectors;

[0049] FIG. 5 a perspective view of a positioning device with positioning arms and battery cell receptacles;

[0050] FIG. 6 a top view of a positioning device and battery cell receptacles;

[0051] FIG. 7 a front view of a positioning device with adjacent battery cell receptacles and vacuum grippers;

[0052] FIG. 8 a perspective rear view of a positioning device with positioning elements arranged on a support element and a vacuum reservoir;

[0053] FIG. 9 a rear view of a positioning device with the closure element in place;

[0054] FIG. 10 a top view of an arrangement of two positioning devices arranged so that adjacent positioning arms each have the same length difference as opposite positioning arms;

[0055] FIG. 11 a front view of a micromodule received in a positioning device;

[0056] FIG. 12 a rear view of a micromodule received in a positioning device.

DETAILED DESCRIPTION

[0057] Example embodiments will now be described more fully with reference to the accompanying drawings.

[0058] FIGS. 1 and 2 each show a battery cell module 100 having a plurality of elongated and cylindrical battery cells 2 arranged in a zigzag shape in a row of two. The zigzag shape runs such that adjacent battery cell pairs 12 each have an offset from one another, with the direction changing after each battery cell pair 12. In this case, one battery cell 2 of each battery cell pair 12 projects into one or two adjacent free spaces of the adjacent battery cell pairs 12, depending on whether the respective battery cell pair 12 is arranged between two further battery cell pairs 12 or on the outside of the battery cell module 100. In this case, the battery cells 2 projecting into the free spaces are each arranged at the level of the midpoint between the longitudinal axes X of the battery cells 2 of the adjacent battery cell pairs 12. The longitudinal axes X of the plurality of battery cells 2 are each aligned parallel to one another. Each battery cell 2 of the first row is in each case opposite a battery cell 2 of the second row, so that these opposite battery cells 2 each form a battery cell pair 12. The battery cell pairs 12 are each connected to one another via a contact sheet 3, which is welded to respective contact surfaces 18 of the battery cells 2. The contact sheets 3 are connected to one another via contact sheet connectors 6, which determine the course of the zigzag shape by means of a diamond shape and by projecting at an angle from the contact sheets 3 in each case. The battery cells 2 are each positioned relative to one another in such a way that the cylindrical surfaces 8 of the battery cells 2 are not in contact and a free space 10 is provided between the battery cells 2 in each case, which is designed for an expected thermally induced circumferential expansion of the battery cells 2. For the dimensioning of the free space 10, on the one hand the thermal expansion to be expected in operation must be taken into account, on the other hand the expansion of the battery cells 2 over their service life and furthermore a tolerance with regard to the positioning of the cells 2 relative to each other during the welding process.

[0059] FIG. 1 shows the upper side 14 of a battery cell module 100, whereby it can be seen that the positive terminals of the battery cells 2 are each aligned towards the upper side 14. This can be seen from the fact that a circular groove is formed between the contact surfaces 18 and the outer edge of the battery cells 2 in each case. The battery cell module 100 is thus connected in parallel. FIG. 2 shows the underside 16 of the battery cell module 100, to which the negative poles of the battery cells are connected in a zigzag manner via respective contact sheets 3 and contact sheet connectors 6. The negative poles can be recognized by the fact that the contact surfaces 18 are flat and do not have circular grooves like the positive poles.

[0060] The spaced positioning of the battery cells 2 relative to one another and the rigid mechanical connection of the battery cells 2 via the contact sheets 3 welded to the top and bottom of the battery cell module 100 and the contact sheet connectors 6 rigidly connected to the contact sheets 3 means that the battery cells 2 are contacted via the contact sheets 3 and the contact sheet connectors 6 on the one hand and are held by them at a distance from one another which is necessary for the thermal expansion of the battery cells 2 during operation. The battery cells 2 are therefore rigidly connected to each other, so that relative movements of connected cells 2 with respect to each other are prevented.

[0061] FIG. 3 shows a top view of a battery cell module 100, wherein the battery cell pairs 12 are each connected to each other via contact sheets 3 (the contact sheet connectors 6 are not shown for illustrative purposes). In particular, it can be seen that a clearance 10 is formed between all the battery cells 2 so that the outer surfaces 8 of the battery cells 2 are not in contact. The zigzag arrangement of the battery cells 2 with respect to each other is selected such that the free spaces 10 of the respective adjacent battery cells 2 are each of equal dimensions, or, respectively, that the distances between the outer surfaces 8 of the adjacent and opposing battery cells 2 are substantially equal. It can be seen that in each case one battery cell 2 of a battery cell pair 12 projects into one or two free spaces 10 of one or two adjacent battery cell pairs 12, and that the longitudinal axes X of these battery cells 2 are in each case at the level of the midpoint between the longitudinal axes X of the battery cells 2 of the one or both adjacent battery cell pairs 12.

[0062] FIG. 4 shows a one-piece embodiment of a sheet or cell connector which has a plurality of contact sheets 3 and a corresponding number of contact sheet connectors 6. The sheet has the zigzag contour described above due to the obliquely extending contact sheet connectors 6. Each of the contact sheets 3 has a central web 22 and two contact sections 20 in each case, the contact sections 20 being intended to be welded to the contact surfaces 18 of the battery cells 2. For adaptation to the cylindrical battery cells 2 and their circular contact surfaces 18, the contact sections 20 each have circular end sections. The center web 22 connects the two contact sections 20 and is dimensioned to span the battery cells 2 to be connected and, moreover, to bridge the clearance 10 to be provided. In the embodiment shown, the contact sections 20 are angled in a shape from the center web 22. This is particularly necessary if the contact areas 18 are recessed above the outer rim of the battery cells 2.

[0063] FIGS. 5-12 show the positioning device 200, which has a carrier sheet 24 on which, in the embodiments shown, eleven positioning elements 26 are arranged parallel to one another in each case. However, the number of positioning elements 26 on the carrier sheet 24 can be scaled down or up in any desired manner. Each positioning element 26 has a positioning arm 30, which is attached to or integrally formed with the carrier sheet 24. A battery cell receptacle 28 is provided at the end of each positioning element 26 remote from the carrier sheet 24. In the embodiments shown, the battery cell receptacles 28 each have two vacuum grippers for picking up and holding battery cells 2 or for subsequently unloading welded battery cell modules 100. Alternatively, it is conceivable that the battery cell receptacles 28 have other means for holding battery cells 2, as well as permanent magnets or electromagnets. For circumferential gripping of battery cells 2, the battery cell receptacles 28 each have an abutment surface with a concave shape. The contact surface extends in the longitudinal direction over at least half of the battery cells 2 to be gripped. The contact surface of the battery cell receptacle 28 extends to a maximum of half around the circumference of the battery cell 2 to be gripped. The concave shape serves in particular to align the battery cells 2 in the respective battery cell receptacle 28 correctly parallel to and at the correct distance from the other gripped battery cells 2. Thus, if a battery cell 2 is unintentionally gripped off-center or not parallel to the battery cell receptacle 28, the concave shape of the battery cell receptacle 28 ensures that the battery cell 2 is pulled in the direction of the vacuum grippers or magnets. The picked-up battery cell 2 is thus centered in the battery cell receptacle 28. A stop is provided at the lower end of each battery cell receptacle 28, which in the embodiments shown is in the form of a protruding lip 29. This stop serves to allow the gripped battery cells 2 to be longitudinally centered in each of the battery cell receptacles 28. It may happen that, although the gripped battery cells 2 are aligned laterally with respect to one another and parallel as described above, these are held at different heights in the respective battery cell receptacles 28 or have different distances from the lips 29. In order to center the cells 2 at one height, provision can be made to briefly release the received battery cells 2 so that they slide down along the contact surfaces onto the respective stops due to their weight force. In this context, releasing means loosening or at least loosening the grip by the vacuum grippers or the electromagnet. Alternatively, it can be provided that the battery cells 2 in the gripped state are pressed down onto the stops 29 by means of a hold-down device, for example in the form of a sheet.

[0064] The vacuum grippers are designed in such a way that the contact surfaces of the battery cell receptacles 28 each have openings 38 which open into vacuum lines which can be provided in the positioning arms 30, as shown in FIGS. 5-7. These vacuum lines 36 open into through-holes 40 on the carrier sheet side, which are shown in FIG. 8 and open into a vacuum reservoir 44 on the rear side of the carrier sheet 24, via which the required vacuum can be provided for the positioning elements. The vacuum reservoir 44 extends to the rear of the carrier sheet 24 in accordance with the lateral spread of the positioning elements 26 and the arrangement of the vacuum grippers in the longitudinal direction of the battery cells 2 to be accommodated in the respective battery cell receptacles 28. For fluid-tight closure of the vacuum reservoir 44, an annular seal 46 is provided which surrounds the reservoir in an annular manner. FIG. 9 shows a closure element 48 for closing the vacuum reservoir 44, which can be attached to the carrier sheet 24 via through-holes 50 in corresponding threaded holes 42 in the carrier sheet 24. The closure element 48 further includes a vacuum port 52 in the form of a through bore opening into the vacuum reservoir 44. The vacuum reservoir can be evacuated via the vacuum port 52, and the vacuum grippers disposed in the battery cell receptacles 28 can be actuated therefrom. Furthermore, the closure element has a receptacle 54 via which the unit comprising positioning elements 26, carrier sheet 24 and closure element 48 can be gripped and fixed by means of a handling module.

[0065] FIGS. 5 and 6 further show that respective adjacent positioning arms 30 have a length difference ΔLy, which results from the length difference L2−L1 of the positioning arms. Furthermore, it is shown that the positioning elements 26 each have a lateral distance ΔLx from each other. If the same free space d is provided between all battery cells 2 in each case and the battery cells 2 each have the same cell diameter Z, the lateral distance ΔLx between the positioning elements 26 is greater by a factor of √{square root over (3)} greater than the difference in length ΔLy of the positioning arms. This results from the fact that with equal distances d between adjacent battery cells 2 with the same cell diameter Z in each case, their longitudinal axes X each form an equilateral triangle whose internal angles α are all 60°. This results in the lateral distance ΔLx of the positioning elements 30:

ΔLx=(Z+d)×sin(α)

and for the length difference ΔLy of the positioning arms 30:

ΔLy=(Z+d)×cos(α),

so that for an angle of 60° the factor:

[00001]$\frac{\Delta \mathrm{Lx}}{\Delta \mathrm{Ly}}=\sqrt{3}\mathrm{follows}.$

[0066] FIG. 10 shows an exemplary arrangement of two positioning devices 200 with respect to each other, which is necessary for manufacturing a battery cell module 100. In this case, a first positioning device 200 is positioned opposite a second positioning device 200 in such a way that the positioning elements 26 each point to one another. The positioning devices 200 are further designed to be complementary to one another, so that a positioning element 26 of length L1 of the second positioning device 200 is assigned opposite each positioning element 26 of length L2 of the first positioning device 200, and a positioning element 26 of length L2 of the second positioning device 200 is assigned opposite each positioning element 26 of length L1 of the first positioning device 200. As a result, positioning elements 26 arranged adjacent to each other on the carrier sheet 24 of the first or the second positioning device 200 have the same length difference ΔLy as respectively opposite positioning elements 26 of the first and the second positioning device 200. The number of positioning elements of length L1 of the first positioning device 200 corresponds to the number of positioning elements of length L2 of the second positioning device 200 and vice versa.

[0067] To produce the battery cell modules 100, each positioning device 100 receives a plurality of battery cells 2 via its battery cell receptacle 28. The cylindrical and elongated battery cells 2 are gripped circumferentially so that the cylindrical outer surface of the battery cells 2 rests against the concave contact surface of the battery cell receptacles 28 and the longitudinal axes X of the battery cells 2 are aligned parallel to one another. Preferably, all positive poles of the accommodated cells 2 can be oriented upwards and all negative poles downwards, or vice versa. To pick up the battery cells 2, the positioning devices 200 can be linearly moved or given away in multiple axes via handling modules. When the battery cells 2 are respectively gripped by the positioning devices 200, they are positioned opposite each other such that the battery cells 2 of both positioning devices 200 are at the same height and all axes X of the cells 2 are aligned parallel to each other. Furthermore, the positive poles and the negative poles of all gripped battery cells 2 preferably each point in the same direction. The positioning devices 200 are positioned opposite each other in such a way that a free space d remains between the respective opposing battery cells 2 and the outer surfaces of the battery cells 2 are not in contact. Accordingly, the distance between two battery cell receptacles is 2Z+d once the positioning devices are moved to their final spaced position. Whereby the final spacing position describes the distance at which the received battery cells 2 are welded together via the cell connector. Subsequently, the battery cells 2 are centered to a height via the stops or the lips 29. This position of the cells relative to each other now corresponds to the desired positioning in the welded state. The preferably one-piece sheet consisting of contact sheets 3 and contact sheet connectors 6 is then placed on the oppositely positioned battery cells 2 and positioned in such a way that each contact surface 18 of each battery cell 2 is assigned a contact section 20. Alternatively, individual contact sheets 3 and contact sheet connectors 6 can be used. The contact sections 20 are then each welded to the associated contact surface 18.

[0068] FIGS. 11 and 12 show an example of a battery cell module 100 held by a positioning device 200, in which the battery cells 2 are mechanically rigidly and electrically connected to one another via the welded-on contact sheets 3 and the contact sheet connectors 6, respectively, with a free space d being formed between all adjacent and opposing cells 2 in each case, so that the individual cells 2 do not touch one another. For illustrative purposes, one of the positioning elements 26 shown is not occupied. For depositing the module 100, this is held and transferred from a positioning device 100 by means of the handling module to a target location and deposited there by applying air to the vacuum grippers or by interrupting the voltage of the electromagnets.

[0069] The features disclosed in the foregoing description, figures, and claims may be significant both individually and in any combination for the realization of the invention in the various embodiments.

[0070] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.