WO2020001861A1

WO2020001861A1 - Battery cell that comprises an integrated heating element

Info

Publication number: WO2020001861A1
Application number: PCT/EP2019/062990
Authority: WO
Inventors: Simon Nuernberger; Christoph Bauer; Simon LUX
Original assignee: Bayerische Motoren Werke Aktiengesellschaft
Priority date: 2018-06-26
Filing date: 2019-05-20
Publication date: 2020-01-02
Also published as: DE102018210417A1

Abstract

The invention relates to a battery cell comprising a first electrode structure, a second electrode structure opposite the first electrode structure and an electrically non-conductive separator separating the two electrode structures. The first electrode structure, the separator and the second electrode structure are arranged lying on top of one another, and at least one heating element is at least partly integrated into at least the first electrode structure and can be electrically heated.

Description

BATTERY CELL WITH INTEGRATED HEATING ELEMENT

The present invention relates to a battery cell, in particular a lithium-ion cell with an integrated heating element.

Many conventional types of batteries have temperature dependencies. For example, ambient temperatures below 0 ° C reduce the battery capacity of lead batteries, NiMH batteries and lithium-ion batteries. In lithium-ion batteries, this effect is caused, for example, by the temperature-dependent conductivity of the electrolyte and the internal resistance. In order to still be able to operate such battery cells efficiently, their housings are usually heated. This requires a considerable amount of energy to raise the temperature inside the battery, since only the housing of the battery cell is heated directly and the interior of the battery only indirectly. The use of these known indirect battery heaters causes a delayed start-up of the batteries and a poor efficiency, since the indirect battery heater significantly heats both the housing and the surroundings of the battery.

In order to eliminate the heating of the surroundings of the battery by the indirect battery heating, a heating layer can be introduced into the electrode stack in battery cells, the electrodes of which are stacked to form a stack. However, the previously known electrode stack arrangements with an integrated heating layer are only suitable for one-off production and prototype structures.

In battery cells in which the electrodes are wound into an electrode roll ("jelly roll"), no electrode structures are known to date which make it possible to introduce a heating layer within the jelly roll. It is particularly advantageous with these battery cells to insert a heating layer between the individual layers of the jelly roll, because a heating layer that is only applied outside the jelly roll leads to unevenly distributed thermal masses and thus to uneven heating of the interior of the Jelly roll. Especially with battery cells with only one and relatively large jelly roll, the distances between the heating layer and the center of the jelly roll are large, what causes the heat generated by the heating layer to reach the center of the jelly roll with a delay.

The present invention is therefore based on the object to further improve the heating of a battery cell, in particular with a view to increasing the homogeneity of the heating of the battery cell during the heating process.

This object is achieved in accordance with the teaching of claim 1. Various embodiments and developments of the invention are the subject of the dependent claims.

A first aspect of the invention relates to a battery cell comprising: (i) a first electrode structure for forming a first electrical pole; (ii) a second electrode structure for forming a second electrical pole having a second polarity opposite to the first pole; (iii) a separator for the spatial and electrical separation of the two electrode structures; and (iv) at least one electrically heated heating element which is at least partially incorporated into one of the electrode structures.

In particular, the first electrode structure can be an anode and the second electrode structure can be a cathode of the battery cell, or vice versa. The heating element can in particular be heated via its electrical resistance, which in particular can be significantly greater than the electrical resistance of the first or the second electrode structure. The separator is electrically non-conductive.

In the context of the invention, “electrical conductivity” is to be understood as a physical quantity which indicates how strong the ability of a substance is to conduct the electrical current. "Electrically conductive" in the sense of the invention is therefore to be understood as an electrical conductivity which (at 25 ° C.) is at least 10 ⁶ S / m (Siemens / meter), ie at least corresponds to the conductivity of metals. Accordingly, a substance is not conductive in the sense of the invention if its electrical conductivity is less than 10 ⁶ S / m. Two objects are therefore "electrically connected" when between them there is an electrically conductive connection. If, on the other hand, there is no or only an electrically non-conductive connection between them, they are "insulated" from one another.

The battery cell according to the invention enables, due to the integration of the at least one heating element in an electrode structure of the battery cell, a more efficient and homogeneous heating of the battery cell, as well as faster start-up and a higher efficiency of the battery cell or the battery it contains.

Preferred embodiments of the battery cell are described below, each of which, as far as this is not expressly excluded or is technically impossible, can be combined with one another as desired and with the other aspects of the invention described below.

In some embodiments, the first electrode structure has a first electrically conductive carrier layer, to which the heating element in the form of a heating layer and a first electrically conductive layer are applied. In addition, the second electrode structure has a second electrically conductive carrier layer, to which a second electrically conductive layer is applied. The first electrode structure, the separator and the second electrode structure form a set of layers with a longitudinal and a transverse direction, and the thickness of this set is substantially constant along the longitudinal and transverse directions. The electrical resistance of the heating layer is greater than the resistance of one of the two carrier layers and greater than the electrical resistance of one of the electrically conductive layers. As a result, the positioning of the heating layer inside the battery cell can be integrated into the series production process of the battery cell. The heating layer can be applied or integrated into the set of layers in a series production process, in particular by known methods (for example gluing, laminating or knife coating), in such a way that the battery cell is mass-produced by simple winding (for example using a winding mandrel) can be. In some embodiments, the heating layer and the first electrically conductive layer are applied to the surface of the first carrier layer facing the separator. The first electrically conductive layer at least partially surrounds the heating layer laterally and the second electrically conductive layer is brought up on the surface of the second carrier layer facing the separator.

As a result, the interior of the battery cell can be heated more efficiently, in particular when the battery cell is designed as a jelly roll, because radiation of the heat generated by the outermost heating layer to the outside is reduced by the first carrier layer.

The side of the first carrier layer facing away from the separator preferably has a third electrically conductive layer and / or the side of the second carrier layer facing away from the separator has a fourth electrically conductive layer. The performance of the battery storage cell can be increased by attaching the third and / or fourth electrically conductive layer on the side of the first or second carrier layer facing away from the separator.

In some embodiments, the heating layer and the first electrically conductive layer have, at least substantially, the same thickness in the longitudinal and transverse directions. This simplifies the manufacturing process for the battery cell and achieves a cylindrical, undeveloped outer surface of the jelly roll.

In some embodiments, the heating layer is at least in places thicker than the first electrically conductive layer, and the second electrically conductive layer has one or more recesses that accommodate the part of the heating layer that projects beyond the first electrically conductive layer. As a result, the resistance of the heating layer can be set in a simple manner and the heating power of the heating layer can thus be adapted.

In some embodiments, the first electrode structure has at least one first contact point, at least one second contact point and at least one ne third contact point. The first contact point and the second contact point are electrically, ie by means of an electrically conductive connection, connected to the heating layer and the third contact point is electrically connected to the first carrier layer. The second electrode structure has at least one fourth contact point electrically connected to the second carrier layer, and the first contact point is connected to the fourth contact point. This simplifies the connection of the heating layer to a switching device which is suitable for connecting the two contact points of the heating layer to the poles of the battery cell.

Preferably, the first and fourth pads are on a first side of the set of layers and the second and third pads are on a second side of the set of layers opposite the first side in the transverse direction. The arrangement of the first and fourth contact points on one side of the battery cell and the second and third contact points on a side opposite this is particularly advantageous when space is limited (on one side).

In some embodiments, the set of layers containing the first electrode structure, the separator and the second electrode structure is rolled along its longitudinal direction via a winding mandrel to form a jelly roll. This provides a battery cell in the form of a jelly roll, the center of which is mechanically supported by a winding mandrel.

In some embodiments, the winding mandrel is heatable and / or the outside of the jelly roll is in thermal contact with the inside of a U- or O-shaped heating layer, but is electrically insulated from it. The heated winding mandrel and the U- or O-shaped heating layer represent additional heaters that additionally support the heating of the battery cell. The U- or O-shaped heating layer has the advantage that it can be easily made from a flat layer by bending / shaping around the Jolly Roll. In some embodiments, the first electrode structure has a first electrically conductive carrier layer and a second electrically conductive carrier layer running at least in sections parallel to the first electrically conductive carrier layer. The mutually facing sides of the first electrically conductive carrier layer and the second electrically conductive carrier layer are coated with a first electrically conductive layer and with a second electrically conductive layer. The heating element between the first and two th electrically conductive layer is arranged in the form of a heating layer lying parallel to the first and two th electrically conductive layers. The electrical resistance of the heating layer over its layer thickness is greater than the corresponding electrical resistance of one of the two electrically conductive layers. In addition, the first electrode structure, the second electrode structure and the separator in between each have a flat shape and are stacked on top of one another. As a result, the positioning of the heating layer inside the battery cell can be easily integrated into the series production process of the battery cell. The heating layer can in particular be introduced into one of the two electrode structures in a series production process using known methods (for example gluing, laminating, knife coating) in such a way that the battery cell can be mass-produced by stacking electrode structures.

In some embodiments, the battery cell further includes: (i) further planar electrode structures separated from each other by separators, each stacked on the first or second electrode structure and separated from them by separators; (ii) a third electrode structure, which is arranged at a first distance from the first electrode structure, and (iii) a fourth electrode structure, which is arranged at a second distance from the third electrode structure, each have a heating element integrated. The first and the second distance are selected such that the thermal mass of those electrode structures which are arranged between the first and third electrode structures corresponds at least substantially to the thermal mass of the electrode structures which are arranged between the third and fourth electrode structures. As a result, the homogeneity of the heating of the electrode structures which are arranged between the first and the fourth electrode structure can be increased. In front- the third and fourth electrode structures preferably have the same structure as the first electrode structure.

In some embodiments, the first distance or the second distance is included in a range from 2 mm to 20 mm. This improves the homogeneity of the heating throughout the stack. The first distance or the second distance is preferably in a range from 6 mm to 7 mm. This can result in a particularly homogeneous heating of the entire stack.

A second aspect of the invention relates to a battery which has two battery cells according to the first aspect of the invention and a cell housing with a cell cover. The cell housing surrounds the battery cells at least partially. A first, a second, a third and a fourth connection point are provided on the cell cover, each of which is electrically insulated, ie not electrically conductively connected, from the cell cover. Each of the two battery cells has a first, a second, a third and a fourth conductor tab on one of their outer surfaces. The first conductor lug of each battery cell is electrically connected to the respective first electrode structure, the second conductor lug and the third conductor lug of each battery cell is electrically connected to the respective heating layer, and the fourth conductor lug of each battery cell is electrically connected to the respective second electrode structure. The first conductor lugs of both battery cells are electrically connected to the first connection point, the second conductor lugs of both battery cells are electrically connected to the second connection point, the third conductor lugs of the battery cells are electrically connected to the third connection point, and the fourth conductor lugs of both battery cells are connected to the fourth Connection point electrically connected. This simplifies the manufacturing process for batteries which contain two battery cells according to the invention, in particular those battery cells whose electrode structures are in particular arranged either in a jelly roll or in a stack. The manufacturing process is particularly simplified in that only two additional connections (for example laser welding connections) per battery are required to provide the external connection points for the heating layers. A third aspect of the invention also relates to a battery which has two battery cells according to the first aspect of the invention and a cell housing with a cell cover. The cell housing at least partially surrounds the battery cells. A first, a second and a third connection point are provided on the cell cover, each of which is electrically insulated from the cell cover. Each of the two battery cells has a first, a second, a third and a fourth conductor tab on one of their outer surfaces. The first conductor tab of each battery cell is electrically connected to the respective first electrode structure, the second and third conductor tabs of each battery cell are electrically connected to the respective heating layer, and the fourth conductor tab of each battery cell is electrically connected to the respective second electrode structure. The first conductor lugs and the second conductor lugs of both battery cells are electrically connected to one another and to the first connection point, the third conductor lugs of both battery cells are electrically connected to the second connection point, and the fourth conductor lugs of both battery cells are electrically connected to the third connection point. This makes it easier to bind the heating layers to a switching device which is suitable for connecting the heating layer to the poles of the battery cell. The connection of the heating layers to a switching device is particularly simplified in that only one additional connection (for example a welded connection) is required for each battery cell. The connection of the first arrester lugs to the second arrester lugs inside the battery cell is an advantage in tight spaces on the cell cover.

Further advantages, features and possible uses of the present invention result from the following detailed description in connection with the figures. At least partially, they show schematically:

1A is a top view of a set of layers of a battery cell suitable for winding into a jelly roll;

Fig. 1B is a jelly roll made by winding up the set of layers

Figure 1A has arisen; 2A shows the cross section of an embodiment of the set of layers shown in FIG. 1A along the point A - A; FIG. 2B shows the cross section of another embodiment of the set of layers shown in FIG. 1A along the point AA;

Figure 3 shows at least part of a stack of layers of another battery cell;

4A shows an embodiment of a battery cell which contains two battery cells, the electrode structures of which are arranged either in a jelly roll or in a stack; and FIG. 4B shows a further embodiment of a battery cell which contains two battery cells, the electrode structures of which are arranged either in a jelly roll or in a stack.

FIG. 1A shows the top view of a set of layers 2 of a battery cell 1. This set of layers, which is not shown in the form of a roll, has a longitudinal direction 5 and a transverse direction perpendicular to this. On one or both transverse sides of the set of layers 2, contact points K1, K2, K3 and K4 are arranged. In FIG. 1B, the set of layers 2 shown in FIG. 1A is shown as a jelly roll, which was created by winding the set of layers 2 over a mandrel 6. 1B shows that the contact points K2 and K3 are arranged on the sides of the set of layers 2 in such a way that there is sufficient space between them for external connections even when the set of layers 2 is a jelly Roll is wound up. The contact points K2 and K3 are preferably arranged on a base surface of the jelly roll in such a way that the winding mandrel 6 stands between them.

FIGS. 2A and 2B show the cross section of two embodiments of the set of layers 2 shown in FIG. 1A along the point A - A. Each of these embodiments 2 ', 2 "has a first electrode structure, 10 or 10', an opposing second electrode structure, 20 or 20 ', and an electrically non-conductive separator, 15 or 15', separating the two electrode structures the first electrode structure, the separator and the second electrode structure are arranged one on top of the other, and at least one heating element, 12 or 12 ', is at least partially incorporated into the first electrode structure 10 or 10'. The heating element is electrically heatable.

In both embodiments, each of the first electrode structures 10, 10 'has a first electrically conductive carrier layer 11 and each of the second electrode structures 20, 20' has a second electrically conductive carrier layer 21. Furthermore, in each of the embodiments, the thickness of the set of layers, 2 'or 2 ", is substantially constant along the longitudinal and transverse directions, which on the one hand facilitates the production of the jelly roll and on the other hand an undeveloped lateral surface of the jelly roll guarantees.

In the embodiment shown in FIG. 2A, a first electrically conductive layer 13 and the heating element in the form of a heating layer 12 are applied to the surface of the first carrier layer 11 facing the separator 15, the first electrically conductive layer 13 at least partially forming the heating layer 12 wisely surrounds laterally. Furthermore, on the surface of the second carrier layer 21 facing the separator 15, a second electrically conductive layer 13 is brought up, which extends in a flat shape over the surface of the second carrier layer 21 facing the separator 15. Also in this embodiment, the heating layer 12 and the first electrically conductive layer 13 have essentially the same height. This allows a flat separator 15 to be used between the two electrode structures 10 and 20 in this embodiment, which simplifies the manufacture of the separator and the set of layers 2 '.

The embodiment shown in FIG. 2B differs from the embodiment shown in FIG. 2A in that the heating layer 12 'is at least locally higher than the first electrically conductive layer 13, the second electrically conductive layer 23' has one or more cutouts 16 ' having, so as to accommodate the part of the heating layer 12 'which protrudes beyond the first electrically conductive layer 13 and the separator 15' where the heating layer 12 'is higher than that of the first electrically conductive layer 13, so deformed / bent is that it is received together with the raised part of the heating layer 12 'by the recesses 16'. Because the height of the heating layer 12 'can be varied in this exemplary embodiment, its resistance and thus its heating output can also be better adjusted or optimized.

In both embodiments 2 'and 2 "the side of the first carrier layer 11 facing away from the separator preferably has a third electrically conductive layer 14 and / or the side of the second carrier layer 21 facing away from the separator has a fourth electrically conductive layer 24 electrical power of the battery cell increased.

In order to be able to fulfill their heating function, the heating layers 12 and 12 ′ have an electrical resistance that is greater than the resistance of one of the two carrier layers and greater than the electrical resistance of one of the electrically conductive layers.

The present invention is not restricted to embodiments in which the heating layer and the first electrically conductive layer are applied to the surface of the first carrier layer facing the separator. Rather, it also includes the embodiments in which the heating layer and the first electrically conductive layer are applied to the surface of the first carrier layer facing away from the separator.

As shown in FIG. 1A, both embodiments 2 'and 2 "of the set of layers 2 have at least a first contact point K1, at least a second contact point K2, at least a third contact point K3 and at least a fourth contact point K4, the first contact point K1 can be connected to one another with the fourth contact point K4 (for example by soldering or welding). It is not shown in the figures that the first contact point K1 and the second contact point K2 are electrically connected to the heating layer 12 or 12 'are connected, the third contact point K3 is electrically connected to the first carrier layer 11 or one of the two electrically conductive layers 13 and 14; and the fourth contact point K4 is electrically connected to the second carrier layer 21 or one of the two electrically conductive layers 23 (or 23 ') and 24. As a result, the poles of the battery cell are guided to the outside on the one hand, and on the other hand the heating layer can be connected to the poles of the battery cell, for example via a switching device.

The first and fourth contact points lie on a first side of the set of layers 2 and the second and third contact points lie on a side opposite this, as shown in FIGS. 1A and 1B, which is particularly advantageous when space is limited.

FIG. 1B shows a battery cell 1, the electrode structures of which are arranged in a jelly roll. This battery cell contains the set of layers 2, which is wound / rolled up along its longitudinal direction 5 via a winding mandrel 6 to form a jelly roll. The first electrode structure and the second electrode structure of the set of layers 2 can be regarded as the cathode or the anode of the battery cell 1. The winding mandrel 6 can be heated, and / or the outside of the jelly roll can be in thermal contact with the inside of a U-shaped or O-shaped heating layer. This is not shown in the figures.

FIG. 3 shows part of a battery cell 3, the electrode structures of which are arranged in a stack 3 as layers lying next to one another (or stacked one on top of the other). The battery cell 3 has a first electrode structure 30, a second electrode structure 29 opposite this and an electrically non-conductive separator 36 which separates the electrode structures, the first electrode structure 30, the separator 36 and the second electrode structure 29 being arranged one above the other / side by side, at least one heating element 35 is at least partially incorporated into the first electrode structure, and the heating element is electrically heatable. In the embodiment shown in FIG. 3, the first electrode structure 30 has a first electrically conductive carrier layer 31 and a second electrically conductive carrier layer 32 parallel to the first electrically conductive carrier layer. The opposite sides of the first electrically conductive support layer 31 and the second electrically conductive support layer 32 are coated with a first electrically conductive layer 33 and with a second electrically conductive layer 34, respectively, and the heating element is in the form of a between the first and second electrically conductive layers Heating layer 35, arranged parallel to the first and second electrically conductive layers. In order to fulfill its heating effect, the heating layer 35 has an electrical resistance which is greater than the electrical resistance of one of the two electrically conductive layers.

Furthermore, the embodiment shown in FIG. 3 has further electrode structures, for example electrode structures 28 and 29, which are separated from one another by separators 36. All of the electrode structures contained in this embodiment and the separators between them have a flat shape and are arranged in a stack. The structure of the electrode structures 28 and 29 is essentially known. For example, both each have two carrier layers 31 '(or 37) with the current conductor 39 (or 38) in between.

In the embodiment shown in FIG. 3, the first electrode structure can be regarded as the anode and the second electrode structure as the cathode of the battery cell. However, the present invention is not limited to this, but rather also includes an embodiment in which the first electrode structure can be regarded as a cathode and the second electrode structure as an anode.

A battery cell, the electrode structures of which are arranged in a stack, as shown, for example, in FIG. 3, contains a multiplicity of heatable electrode structures, which have a structure corresponding to the first electrode structure 30, and a multiplicity of electrode structures, which cannot be heated (e.g. the electrode structures 28 and 29). The heated electrode structures 30 are distributed in the stack so that the non-heated electrode Structures, which are arranged between two successive heatable electrode structures, form a group with a thermal mass (heat capacity), and the thermal masses of the groups thus formed are essentially the same.

For example, the embodiment shown in FIG. 3 can have further flat electrode structures separated from one another by separators 36, including a third and a fourth heatable electrode structure, the first, third and fourth heatable electrode structures in this order, successively in the order Arranged stack, the third electrode structure is arranged at a first distance from the first electrode structure 30, the fourth electrode structure is arranged at a second distance from the third electrode structure, and the first and second distance are selected so that the thermal mass of the electrode structures, which are arranged between the first and third electrode structures is substantially the same as the thermal mass of the electrode structures which are arranged between the third and fourth electrode structures. This is the case if the first distance and the second distance are in a range from 2 mm to 20 mm. With such a distribution of the electrode structures provided with a heating layer in the stack, a more homogeneous heating of the stack can be achieved. The heating of the stack is homogeneous when the first distance and the second distance are in a range from 6 mm to 7 mm. The third and fourth electrode structure, which preferably have a structure corresponding to the first electrode structure, are not shown in FIG. 3.

FIG. 4A shows a battery which contains two battery cells 40 and 50 according to the invention, the electrode structures of which are arranged either in a jelly roll or in a stack. Furthermore, the figure shows a cell cover 60 that fits into a cell housing that is to accommodate the two battery cells 40 and 50. The cell cover 60 not only has two connection points for the battery poles, but four, namely a first connection point 61, a second connection point 62, a third connection point 63 and a fourth connection point 64, all of which are electrically insulated from the cell cover. Are the Electrode structures of the two battery cells 40 and 50 arranged in a jelly roll, each of the two battery cells has on one of its bases a first conductor tab 41 and 51, a second conductor tab 42 and 52, a third conductor tab 43 and 53, and one fourth arrester lug 44 or 54. If, however, the electrode structures of the two battery cells 40 and 50 according to the invention are arranged in a stack, each of the two battery cells has the conductor tabs on one of their side surfaces. The first conductor tab of each battery cell is electrically connected to the respective first electrode structure (e.g. anode), the second and third conductor tab of each battery cell with the respective heating layer and the fourth conductor tab of each battery cell is connected to the respective second electrode structure (e.g. cathode). The first conductor tabs of both battery cells are electrically connected to the first connection point 61 and the fourth conductor tabs of both battery cells are connected to the fourth connection point 64. In addition, the second conductor lugs of both battery cells are electrically connected to the second connection point 62 and the third conductor lugs of both battery cells are connected to the third connection point 63. Each arrester lug is directly / directly electrically connected to its respective connection point, for example by welding or soldering the arrester lugs to the respective connection point.

FIG. 4B shows a battery which contains two battery cells 70 and 80 according to the invention, the electrode structures of which are arranged either in a jelly roll or in a stack. Furthermore, the figure shows a cell cover 90 that fits into a cell housing that is to accommodate the two battery cells 70 and 80. The cell cover 90 has three connection points, namely a first connection point 91, a second connection point 92 and a third connection point 93, all of which are electrically insulated from the cell cover. If the electrode structures of the two battery cells 70 and 80 are arranged in a jelly roll, then each of the two battery cells has a first conductor tab 71 or 81, a second conductor tab 72 or 82, a third conductor tab 73 or 83, and a fourth arrester lug 74 or 84. If, however, the electrode structures of the two battery cells 70 and 80 according to the invention are arranged in a stack, each of the two battery cells has the conductor tabs on one of its side faces. The first arrester flag each battery cell is electrically connected to the respective first electrode structure (for example anode), the second and third conductor lugs of each battery cell with the respective heating layer and the fourth conductor lug of each battery cell with the respective second electrode structure (for example cathode). On the one hand, the first conductor tabs of both battery cells are electrically connected to the first connection point 91 and the fourth conductor tabs of both battery cells are electrically connected to the third connection point 93. On the other hand, the second conductor tabs of both battery cells 70 and 80 are electrically connected to the first connection point 91 and the third conductor tabs of both battery cells 70 and 80 are connected to the third connection point 92.

In the battery cell shown in FIG. 4B, the first, third and fourth conductor lugs of both battery cells 70 and 80 are directly / directly electrically connected to the respective connection point, for example by laser welding or soldering the conductor lugs to the respective connection point.

The second conductor tabs of the battery cells 70 and 80 can be electrically connected directly to the first connection point of the cell cover. However, the first conductor tabs and the second conductor tabs are preferably connected to one another in the interior of the battery cell, and thus the second conductor tabs are only electrically connected to the first connection point 91, but not directly (for example by soldering or welding). Therefore, the second arrester tabs 72 and 82 are only drawn in broken lines in FIG.

In FIGS. 4A and 4B, the conductor tabs of the two battery cells 40 and 50 (or 70 and 80) essentially form a right angle with the base surface (or side surface) from which they protrude; and the two battery cells 40 and 50 (or 70 and 80) are arranged with respect to the cell cover 60 (or 90) in such a way that their laterally protruding conductor tabs are essentially parallel to the cell cover 60 (or 90) and stand above the respective connection points of the cell cover. After the conductor tabs are connected to the respective connection points of the cell cover (e.g. by soldering or welding), the conductor tabs are bent / deformed so that the two battery cells 40 and 50 (or 70 and 80) next to each other one side of the cell cover 60 (or 90). The two battery cells standing next to each other are inserted into a suitable cell housing, and the cell cover is welded to the cell housing. The walls of the cell housing can be heated and can be in thermal contact with the two battery cells 40 and 50 (or 70 and 80). This additionally supports the heating of the battery cells.

While at least one exemplary embodiment has been described above, it should be noted that a large number of variations exist. It should also be noted here that the exemplary embodiments described are only non-limiting examples, and it is not intended to thereby limit the scope, the applicability or the configuration of the devices and methods described here. Rather, the preceding description will provide the person skilled in the art with instructions for implementing at least one exemplary embodiment, it being understood that various changes in the mode of operation and arrangement of the elements described in an exemplary embodiment can be carried out without the the attached subject matter as well as its legal equivalents are deviated from.

LIST OF REFERENCE NUMBERS

1 battery cell in the form of a jelly roll

2, 2 ', 2 set of layers for winding into a jelly roll

3 stacks of layers

5 Longitudinal direction of the set of layers

6 mandrel

10, 10 'First electrode structure, for example cathode

1 1 Electrically conductive carrier layer, for example the cathode

12, 12 'heating layer

13 Electrically conductive layer

14 Electrically conductive layer

15, 15 'separator

16 'recess in an electrically conductive layer

20, 20 'Second electrode structure, for example anode

21 Electrically conductive carrier layer, for example the anode

23, 23 'Electrically conductive layer

24 Electrically conductive layer

28 Known electrode structure in a stack, for example anode 29 Known electrode structure in a stack, for example cathode

30 First electrode structure, for example anode

31, 31 'Electrically conductive carrier layer, for example anode layer

32 Electrically conductive carrier layer, for example anode layer

33 current arrester (electrically conductive layer),

34 current arrester (electrically conductive layer)

35 heating layer

36 separator

37 Electrically conductive carrier layer, for example cathode layer

38 current arrester (electrically conductive layer)

39 current arrester (electrically conductive layer)

40 First battery storage unit (jelly roll or stack arrangement)

41 - 44 arrester tabs of the first battery storage unit

50 second battery storage unit (jelly roll or stack arrangement)

51 - 54 arrester lugs of the second battery storage unit 60 cell covers with four connection points

61 - 64 connection points of the cell cover

70 First battery storage unit (jelly roll or stack arrangement)

71 - 74 arrester tabs of the first battery storage unit

80 Second battery storage unit (jelly roll or stack arrangement)

81 - 84 arrester tabs of the second battery storage unit

90 cell covers with three connection points

91 - 93 Connection points of the cell cover

Claims

EXPECTATIONS

1 battery cell:

a first electrode structure (10, 10 ', 30) for forming a first electrical pole;

a second electrode structure (20, 20 ') for forming a second electrical pole with a polarity opposite to that of the first pole;

a separator (15, 15 ') for the spatial and electrical separation of the two electrode structures; and

at least one electrically heated heating element (12, 12 ', 35) which is at least partially incorporated into one of the electrode structures.

2. The battery cell of claim 1, wherein:

the first electrode structure (10,

10 ') has a first electrically conductive carrier layer (11), to which the heating element in the form of a heating layer (12, 12') and a first electrically conductive layer (13) are arranged next to one another;

the second electrode structure (20, 20 ') has a second electrically conductive carrier layer (21) to which a second electrically conductive layer (23, 23') is applied;

the first electrode structure, the separator and the second electrode structure form a set of layers (2) with a longitudinal and a transverse direction and the thickness of this set along the longitudinal and transverse directions is substantially constant; and

the electrical resistance of the heating layer is greater than the resistance of one of the two carrier layers and greater than the electrical resistance of one of the electrically conductive layers. 3. The battery cell of claim 2, wherein:

the heating layer (12, 12 ') and the first electrically conductive layer (13) on the surface of the first carrier layer facing the separator (15, 15')

(1 1) are applied; the first electrically conductive layer also at least partially surrounds the heating layer laterally; and

the second electrically conductive layer (23, 23 ') is applied to the surface of the second carrier layer (21) facing the separator (15, 15').

Battery cell according to claim 3, wherein the heating layer (12) and the first electrically conductive layer (13), at least substantially, have the same thickness in the longitudinal and transverse directions.

The battery cell according to claim 3, wherein the heating layer (12 ') is at least in places thicker than the first electrically conductive layer (13), and the second electrically conductive layer (23') has one or more recesses (16 ') which form the part the heating layer that protrudes beyond the first electrically conductive layer.

A battery cell according to any one of claims 2 to 5, wherein:

the first electrode structure (10, 10 ') has at least one first contact point (K1), at least one second contact point (K2) and at least one third contact point (K3), the first contact point and the second contact point being electrically connected to the heating layer (12,

12 ') are connected, and the third contact point (K3) is electrically connected to the first carrier layer (11); and

the second electrode structure (20, 20 ') has at least one fourth contact point (K4) electrically connected to the second carrier layer (21), and the first contact point (K1) is connected to the fourth contact point (K4).

The battery cell according to one of claims 2 to 5, wherein the set (2) of layers comprising the first electrode structure (10, 10 '), the separator (15, 15') and the second electrode structure (20, 20 ') along its longitudinal direction (5) rolled up into a jelly roll via a mandrel (6). Battery cell according to claim 7, wherein the winding mandrel is electrically heatable; and or

the outside of the jelly roll is in thermal contact with the inside of a U- or O-shaped heating structure, but is electrically insulated from it.

The battery cell of claim 1, wherein:

the first electrode structure (30) has a first electrically conductive carrier layer (31) and a second electrically conductive carrier layer (32) running at least in sections parallel to the first electrically conductive carrier layer;

the mutually facing sides of the first electrically conductive carrier layer (31) and the second electrically conductive carrier layer (32) are coated with a first electrically conductive layer (33) and with a second electrically conductive layer (34);

the heating element is arranged between the first and second electrically conductive layers in the form of a heating layer (35) lying parallel to the first and second electrically conductive layers;

the electrical resistance of the heating layer over its layer thickness is greater than the corresponding electrical resistance of one of the two electrically conductive layers; and

the first electrode structure (30), the second electrode structure (29) and the intermediate separator (36) each have a flat shape and are stacked on top of one another.

The battery cell according to claim 9, further comprising further plane-shaped electrode structures separated from one another by separators (36), each of which is stacked on the first electrode structure (30) or the second electrode structure (29), and by these by separators (36 ) are separated;

wherein a third electrode structure, which is arranged at a first distance from the first electrode structure (30), and a fourth electrode structure, which is arranged at a second distance from the third electrode structure, each have a heating element integrated; and the first and second distances are selected such that the thermal mass of those electrode structures which are arranged between the first and third electrode structures corresponds at least substantially to the thermal mass of the electrode structures which are arranged between the third and fourth electrode structures.

The battery cell according to claim 10, wherein the first distance or the second distance or both are each in a range from 2 mm to 20 mm, preferably the first and the second distance are each in a range from 6 mm to 7 mm.

Battery, comprising:

two battery cells (40.50), each according to one of the preceding claims 7 to 1 1; and

a cell housing with a cell cover (60);

in which:

the cell housing at least partially surrounds the battery cells (40, 50); a first, a second, a third and a fourth connection point (61, ..., 64) are provided on the cell cover (60), each of which is electrically insulated from the cell cover;

each of the two battery cells (40, 50) has a first, a second, a third and a fourth conductor tab (41, ..., 44; 51, ..., 54) on one of their outer surfaces;

the first conductor lug (41, 51) of each battery cell with the respective first electrode structure, the second conductor lug (42,52) and the third conductor lug (43,53) of each battery cell with the respective heating layer and the fourth conductor lug (44,54) each Battery cell is electrically connected to the respective second electrode structure; and

the first conductor lugs (41, 51) of both battery cells (40, 50) are electrically connected to the first connection point (61), the second conductor lugs (42, 52) of both battery cells are electrically connected to the second connection point (62), the third Discharge tabs (43, 53) of both battery cells are electrically connected to the third connection point (63) and the fourth conductor tabs (44, 54) of both battery cells are electrically connected to the fourth connection point (64).

13. Having battery:

two battery cells (70, 80), each according to one of claims 7 to 1 1; and

a cell housing with a cell cover (90);

in which:

the cell housing at least partially surrounds the battery cells (40, 50); on the cell cover (90) a first, a second and a third connection point (91, ..., 93) are provided, each of which is electrically insulated from the cell end;

each of the two battery cells (70, 80) has a first, a second, a third and a fourth conductor tab (71, ..., 44; 81, ..., 84) on one of their outer surfaces;

the first conductor tab (71, 81) of each battery cell with the respective first electrode structure, the second (72.82) and third conductor tab (73.83) of each battery cell with the respective heating layer and the fourth conductor tab (74.84) of each battery cell is electrically connected to the respective second electrode structure; and

the first conductor tabs (71, 81) and the second conductor tabs (72, 82) of both battery cells are electrically connected to one another and to the first connection point (91), the third conductor tabs (73, 83) of both battery cells to the second connection point (92) electrically connected, and the fourth conductor tabs (74, 84) of both battery cells are electrically connected to the third connection point (93).