Cell module for a battery system

Abstract

Cell module (10) for a battery system, comprising: - at least two individual cells (20) which are electrically interconnected to provide a module voltage of the cell module (10), - at least one electric heating mat (30) for heating the individual cells (20), wherein the heating mat (30) is integrated in the cell module (10) and is electrically connected to at least one of the individual cells (20) in order to provide a power supply to the heating mat (30) via the module voltage, wherein at least one conductor element (60) is provided, which comprises an electronics (61) of the cell module (10) and the at least one heating mat (30), wherein the conductor element (60) is arranged between the individual cells (20) and has a bend so that the shape of the conductor element (60) is adapted to the arrangement of the individual cells (20) in the cell module (10).

Description

The present invention relates to a cell module for a battery system. The invention further relates to a battery system having at least two cell modules.It is known from the prior art that in cell modules for a battery system, heating of the individual cells can be carried out by an external supply of heat.DE 10 2013 015 757 A1 discloses a cell block for a battery having a plurality of individual cells electrically connected to one another in series and / or in parallel and at least one temperature control device arranged on the cell block.DE 10 2005 022 204 B4 discloses a method for heating a battery in a vehicle having a battery heater.DE 10 2015 010 983 A1 discloses a battery having a plurality of individual cells or cell blocks electrically connected to one another in parallel, and a basic tempering device for basic tempering of all individual cells.Further batteries with temperature control devices are disclosed in DE 10 2015 010 925 A1, U.S. Pat. No. 2016 / 0 028 128 A1 and DE 0 857 348 T1.It is frequently disadvantageous in the known solutions that a complicated interconnection and an increased space requirement are necessary in order to provide the heating, for example via heating devices. It is therefore an object of the present invention to at least partially eliminate the disadvantages described above. In particular, it is an object of the present invention to reduce the complexity of the cell module required for providing the heating.The above object is achieved by a cell module having the features of claim 1 and by a battery system having the features of claim 8. Features and details which are described in connection with the cell module according to the invention naturally also apply in connection with the battery system according to the invention, and vice versa, so that with regard to the disclosure reference is or can always be made to the individual aspects of the invention in a mutually alternating manner.The object is achieved in particular by a cell module for a battery system, in particular for a vehicle, having:at least two individual cells, preferably pouch cells, which are electrically interconnected to one another in order to provide an (electrical) module voltage of the cell module,at least one electric heating mat for heating the individual cells.In this case, it is provided that the at least one heating mat is integrated in the cell module and is electrically connected to at least one of the individual cells in order to provide an energy supply of the at least one heating mat via the module voltage (i.e. optionally also at least a part of the module voltage, e.g. only via the voltage of the at least one connected individual cell). This has the advantage that the operation of the heating mat can be made possible independently of external voltage sources, i.e. preferably can be provided completely by the cell module. In this way, the interconnection outlay and the complexity of the cell module are significantly reduced.In this case, it is also a further advantage in particular that improved operation of the cell module is possible by the heating by means of the at least one heating mat. This is primarily associated with the fact that the internal resistance deteriorates at low temperatures due to the influence of the electrolyte on the internal resistance. This effect has an influence on the performance of the cells and thus also on the performance of a vehicle in which the cell module can optionally be used.A heating mat can advantageously comprise at least one heating element, e.g. at least one heating wire or the like, which is electrically operated for heating. The heating mat is characterized in particular by a flat shape and thus preferably has a much greater (for example at least 10 times or at least 100 times) extension in the longitudinal and width direction than in the depth. A heating mat is optionally also understood to mean a heating film which is designed to be flexible in a deformable and / or bendable manner. Due to the electric current flow through the heating element, which is made possible by means of the energy supply of the heating mat, heat radiation can occur in this case. This can be suitable for heating the individual cells of the cell module and thus optimizing the operation of the individual cells. It can be decisive here that the heating mat is operated primarily and in a targeted manner for heating the individual cells, that is to say it is not merely a parasitic heating.For example, it can be provided that the energy supply of the at least one heating mat is provided exclusively via the module voltage, that is to say an autonomous energy supply of the heating mat is used in the sense of a self-supplying system, wherein at least a part of the module voltage is preferably supplied to the heating mat for this purpose, wherein the module voltage is preferably provided by the individual cells and / or via an electrical connection of the cell module. The connection, preferably a high-voltage connection, is used, for example, for tapping off the cell voltage of the individual cells, i.e., the module voltage, and / or for charging the individual cells. For this purpose, the connection is formed in particular on the outside of the cell module, i.e. is configured such that it can be contacted from the outside of the cell module. For example, the connection serves for electrical connection to further cell modules in a battery system and / or for connection to vehicle electronics and / or an on-board power supply system. To provide the connection, at least one or two terminals can be fastened to a housing of the cell module, for example. Via electrical conductors in the housing, the connection can be connected internally to the individual cells and / or the heating mat. This has the advantage that no additional external connections have to be provided for providing the energy supply of the heating mat.For the energy supply of the at least one heating mat, the latter can have, for example, an electrical supply terminal which is electrically connected to at least one voltage tap of at least one of the individual cells via an electrical conductor, such as at least one conductor track, a cable or the like. Since the voltages of the individual cells can together form the module voltage, at least a part of the module voltage can be tapped in this way for the energy supply of the heating mat. This has the advantage that the energy supply can be provided internally, that is to say a dedicated external voltage supply for the heating mat can be dispensed with. In other words, it is not necessary for a separate heating mat connection to be used for the energy supply for starting up the at least one heating mat. It is thus possible for the heating mat to be operated "autonomously" by the cell module. In this way, the cell module can be provided as a closed system. In addition, it can be provided that the module voltage is also supplied externally, in particular via high-voltage connections of the cell module. However, this is not a dedicated energy supply for the heating mat, but rather an external provision of the module voltage. This externally provided module voltage is used in particular primarily to supply the individual cells with current, e.g. to charge them up. Only secondarily in this case is this module voltage also used in this case for supplying energy to the at least one heating mat. In the case of fully charged individual cells, the module voltage and thus also the energy supply of the at least one heating mat can also be provided exclusively internally by the individual cells.Furthermore, in the cell module according to the invention, at least one conductor element is provided, which has an electronics of the cell module and the at least one heating mat. A conductor element is understood to mean, for example, a (in particular flexible) circuit board or circuit or else a composite thereof or the like. The conductor element has the at least one heating mat, for example, in such a way that at least some of the components of the heating mat are formed by electrical conductors of the conductor element. For example, the conductor element can have heating wires of the at least one heating mat. This has the advantage that a space-saving and cost-effective integration of the heating mat in the cell module is possible.Advantageously, it is provided that the individual cells are interconnected in parallel or in series with one another, and thus provide the module voltage (e.g. depending on the circuit as the sum of the voltages at the individual cells or corresponding to the voltage of an individual cell). For this purpose, at least one module voltage tap of this interconnection of the individual cells can be provided, for example via at least one electrically conductive connection of respective connections of the individual cells. In order to supply the at least one heating mat with energy, i.e. in order to enable a heating operation of the heating mat, at least one of the individual cells can provide a voltage supply for the heating mat. In other words, the energy supply can be provided via the module voltage, i.e. the voltages of the individual cells. It is advantageous here if the proportion of the module voltage which is used for the energy supply is adapted to a specification of the heating mat (that is to say in particular to the energy requirement). For this purpose, a corresponding circuit of the cell module can be used, which can be provided at least partially by an electronic and / or conductor element, for example a voltage divider or the like.It is also advantageous if the conductor element is designed as a flexible printed circuit board, and preferably at least a part of the heating mat, in particular at least one component of the heating mat, is printed on a carrier element (of the conductor element). For this purpose, it is possible, for example, for heating ink, in particular PTC heating ink, to be printed on the printed circuit board or on the carrier element in order to provide a heating element (PTC stands for "positive temperature coefficient"). This achieves the advantage that the heating mat can be accommodated in the cell module in a space-saving manner.The conductor element can be embodied, for example, as at least one printed circuit board, in particular a flexible printed circuit board. Below a flexible printed circuit board, an FPC (Engl. Flexible printed circuit) is understood to mean an arrangement with printed electrical conductor tracks and / or circuits, which are preferably formed on a flexible base material. This has the advantage that the printed circuit board can be designed to be flexible and can therefore optionally also be brought into different shapes and geometries (e.g. wound or bent). The conductor tracks and circuits can be printed on the base material, for example, with an electrically conductive ink. The base material is embodied, for example, as a carrier element, in particular a carrier film, and is preferably produced from polyimide and / or polyester. The conductor element can have a thickness of a maximum of 10 micrometers and / or a bending radius of a maximum of 1 mm.Furthermore, it is provided within the scope of the invention that the conductor element is arranged between the individual cells, i.e. between at least two individual cells of the cell module, and in particular between all adjacent individual cells of the cell module. The conductor element has a bend, so that the shape of the conductor element is adapted to the arrangement of the individual cells in the cell module. The conductor element can be guided and / or wound and / or wound at least partially around the individual cells and / or run in a serpentine manner in the cell module, for example, in order advantageously to thus achieve space saving. Furthermore, the energy efficiency can be improved by an arrangement directly on the individual cells, since the heat does not first have to be transported to the cells via a plurality of material layers.Furthermore, it is optionally possible for the conductor element and / or the heating mat to be formed in one piece, and / or for only a single conductor element and / or for only a single heating mat to be provided in a cell module. It is advantageous here if exactly one conductor element and / or exactly one heating mat is provided in a cell module, since this can be arranged between many or all individual cells due to the flexibility or flexibility, i.e. no further conductor elements or heating mats are necessary for extensive and large-area heating. Alternatively or additionally, a plurality of conductor elements and / or heating mats can also be provided, which are each arranged - in particular sandwiched - between individual cells.Preferably, it can be provided that the conductor element is formed as a flat conductor with a flexible carrier film as carrier element, and is preferably formed as a flexible printed circuit. This allows flexible and adaptable integration in the cell module.A further advantage within the scope of the invention can be achieved if an electronics of the cell module has at least one electronic switch element which electrically connects the at least one heating mat to the at least one individual cell in order to switch the energy supply of the heating mat, wherein the switch element is preferably designed to be activatable externally via a connection (e.g. a pin). Alternatively or additionally, the electronics of the cell module can have a temperature sensor system in order to detect the temperature in the cell module and / or the individual cells. In this way, the heating of the individual cells can be regulated particularly advantageously via the at least one heating mat, e.g. automatically via an electronic control and / or regulation unit. For example, the detected temperature is evaluated by the control and / or regulating unit in order to actuate the switch element as a function thereof. The switching element, such as a transistor or relay or the like, controls a current flow to the at least one heating mat, for example, in order to regulate the heating and thus influence the temperature of the individual cells.In a further possibility, it can be provided that the at least one heating mat is arranged between each pair of adjacent individual cells, and preferably directly contacts the respective individual cells, wherein preferably at least four or at least eight or at least 10 individual cells are integrated in the cell module. This enables particularly efficient heating, in particular by a sandwich-like arrangement of the heating mat.Optionally, in embodiments of the cell module according to the invention, it is provided that an electrical connection, in particular a high-voltage connection, is arranged on a housing of the cell module for electrical connection to an external electrical system, as a result of which the module voltage can be provided and / or influenced externally. The external electrical system is, for example, vehicle electronics or a component of an on-board power supply system, in particular a high-voltage on-board power supply system, of the vehicle and / or a voltage source or a battery management system or the like.The invention likewise relates to a battery system for a vehicle having at least two cell modules, preferably cell modules according to the invention, each having:at least two individual cells which are electrically interconnected to one another in order to provide a module voltage of the cell module,at least one electric heating mat for heating the individual cells.In this case, it is provided that the heating mat is integrated in the cell module and is electrically connected to at least one of the individual cells in order to provide the energy supply to the heating mat via the voltage of this at least one individual cell, that is to say via the module voltage. The battery system according to the invention thus brings with it the same advantages as have been described in detail with reference to a cell module according to the invention. The battery system and the individual cells can be embodied in a rechargeable manner, and thus form, for example, a rechargeable energy store (rechargeable battery) for a vehicle.The vehicle is designed, for example, as a trackless agricultural vehicle, preferably with a high-voltage on-board power supply system and / or an electric motor. In particular, the vehicle is designed as a passenger motor vehicle and / or electric vehicle and / or hybrid vehicle. In embodiments of electric vehicles, an internal combustion engine is preferably not provided in the vehicle, and is then driven exclusively by electrical energy.Further advantages, features and details of the invention will become apparent from the following description, in which exemplary embodiments of the invention are described in detail with reference to the drawings. The features mentioned in the claims and in the description can be essential to the invention individually or in any combination. They show in each case schematically: FIG. 1 shows a perspective view of a cell module according to the invention, FIG. 2 shows a further perspective view of a cell module according to the invention, FIG. 3 shows an exploded illustration of a cell module according to the invention, FIG. 4 shows a further exploded illustration of a cell module according to the invention, FIG. 5 shows an electronic system of the cell module.In the following figures, the identical reference numerals are also used for the same technical features of different exemplary embodiments.FIG. 1 schematically shows a cell module 10 according to the invention, in which a housing 40 of the cell module 10 can be seen in the assembled state. At least one heating mat 30, which serves for heating individual cells 20 of the cell module 10, is not visible from the outside. Thus, the at least one heating mat 30 is completely integrated in the cell module 10. The housing 40 has at least one front end plate 41, a bottom 42 and at least one side wall 43. A heating mat 30 can optionally be provided on each of these housing elements 41, 42, 43. This enables heating with high heating efficiency, which is matched to the arrangement of the individual cells 20.It can also be seen that a connection 50, i.e. a terminal of the cell module 10, is arranged on the housing 40. This makes it possible to establish an electrically conductive connection to the individual cells 20 and thereby to tap off the module voltage.A particular advantage results from the fact that this module voltage is also used for supplying energy to the at least one heating mat 30. Thus, no further external connection is necessary for the energy supply of the heating mat 30.It can be seen in FIG. 2 that the heating mat 30 can be arranged on a large surface on a housing side (e.g. a housing element 41, 42, 43), extends in particular completely or predominantly or at least to an extent of 90% on this housing side or on this housing element 41, 42, 43. In this case, the heating mat 30 according to FIG. 2 can extend on the top side or (alternatively or additionally) according to FIG. 3 on the bottom 42 of the housing 40, in order to provide the most efficient possible heating of the individual cells 20.According to FIG. 3, it can be seen on the basis of the schematic illustration shown therein that the heating mat 30 can be integrated in a conductor element 60, for example a flexible printed circuit board. In addition to the components of the heating mat 30, this can also have conductor tracks and / or an electronics 61 of the cell module 10. The electronics 61 is shown in FIG. 5 by way of example with a switch element 63 and a temperature sensor system 64. It can also be seen that the printed circuit board can have a carrier element 62 as the base material, which is designed in particular to be flexible and bendable.An advantage of the flexible configuration of the carrier element 62 and thus also of the heating mat 30 is evident with reference to FIG. 4. Thus, the heating mat 30 can be laid and / or wound flexibly and uniformly between the individual cells 20 in order to transfer the heat to the individual cells 20 in a manner as space-saving as possible. It is also possible, if appropriate, for a plurality of heating mats 30 to be provided, which are formed, if appropriate, separately and / or at a distance from one another. Thus, for example, at least two or at least three or at least 5 heating mats 30 or at least one heating mat 30 per individual cell 20 can be provided. Depicted in FIG. 4 by way of example is a first heating mat 31 and a second heating mat 32 and an nth heating mat 34, wherein n can be any desired positive integer. Alternatively or additionally, a heating mat 30 can also be arranged in the region of a housing element 44.The foregoing explanation of the embodiments describes the present invention solely by way of examples. Of course, individual features of the embodiments can be freely combined with one another, insofar as technically expedient, without departing from the scope of the present invention.List of reference characters10 Cell module 20 Individual cell 30 Heating mat 31 First heating mat 32 Second heating mat 34 Nth heating mat 40 Housing 41 End plate 42 Base 43 Side wall 44 Further housing element 50 Connection, terminal 60 Conductor element, flexible printed circuit board 61 Electronics 62 Carrier element 63 Switch element 64 Temperature sensor system

Claims

Cell module (10) for a battery system, having: - at least two individual cells (20) which are electrically interconnected to one another in order to provide a module voltage of the cell module (10), - at least one electrical heating mat (30) for heating the individual cells (20), wherein the heating mat (30) is integrated in the cell module (10) and is electrically connected to at least one of the individual cells (20) in order to provide an energy supply of the heating mat (30) via the module voltage, wherein at least one conductor element (60) is provided which has an electronics system (61) of the cell module (10) and the at least one heating mat (30), wherein the conductor element (60) is arranged between the individual cells (20) and has a bend, such that the shape of the conductor element (60) is matched to the arrangement of the individual cells (20) in the cell module (10).Cell module (10) according to Claim 1, characterized in that the energy supply of the at least one heating mat (30) is provided exclusively via the module voltage, at least some of the module voltage being supplied to the heating mat (30) for this purpose, the module voltage being provided by the individual cells (20) and / or via an electrical connection (50) of the cell module (10).Cell module (10) according to Claim 1 or 2, characterized in that the conductor element (60) is designed as a flexible printed circuit board, and at least one component of the heating mat (30) is printed on a carrier element (62) of the printed circuit board.Cell module (10) according to Claim 3, characterized in that the conductor element (60) is designed as a flat conductor with a flexible carrier film as carrier element (62), and is preferably designed as a flexible printed circuit.Cell module (10) according to one of the preceding claims, characterized in that an electronic system (61) of the cell module (10) has at least one electronic switch element (63), which electrically connects the at least one heating mat (30) to the at least one individual cell (20) in order to switch the energy supply of the heating mat (30), wherein the switch element (63) is preferably designed to be activatable externally via a connection (50).Cell module (10) according to one of the preceding claims, characterized in that the at least one heating mat (30) is arranged between each pair of adjacent individual cells (20), and preferably makes direct contact with the respective individual cells (20), wherein preferably at least four or at least eight or at least 10 individual cells (20) are integrated in the cell module (10).Cell module (10) according to one of the preceding claims, characterized in that an electrical high-voltage connection for electrical connection to an external electrical system is provided on a housing (40) of the cell module (10), as a result of which the module voltage can be provided and / or influenced externally.Battery system for a vehicle having at least two cell modules (10), each having: - at least two individual cells (20) which are electrically interconnected with one another in order to provide a module voltage of the cell module (10), - at least one electrical heating mat (30) for heating the individual cells (20), wherein the heating mat (30) is integrated in the cell module (10) and is electrically connected to at least one of the individual cells (20) in order to provide the energy supply of the heating mat (30) via the module voltage, wherein at least one conductor element (60) is provided which has an electronics system (61) of the cell module (10) and the at least one heating mat (30), wherein the conductor element (60) is arranged between the individual cells (20) and has a bend, such that the shape of the conductor element (60) is matched to the arrangement of the individual cells (20) in the cell module (10).

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