DE102017216786B4 - Vehicle battery with several cell modules and at least one cell module monitoring device - Google Patents

Abstract

Vehicle battery (12) with a plurality of cell modules (10) and with at least one cell module monitoring device (1), comprising a first component (4) which comprises an evaluation unit (4.1) and a wireless communication device (4.2, 4.3), and an at least partially flexible carrier plate (2), wherein the at least partially flexible carrier plate (2) has a region (3) in which the first component (4) is arranged, wherein each of the cell modules (10) is coupled to the at least one cell module monitoring device (1) by means of at least one line (8) which is arranged on the at least partially flexible carrier plate (2), characterized in that the lines (8) are arranged evenly distributed over the entire surface of the at least partially flexible carrier plate (2), so that heat released by the lines (8) is evenly distributed over the at least partially flexible carrier plate (2), wherein the at least partially flexible carrier plate (2) is arranged near the cell modules (10) in such a way that the at least partially flexible Carrier plate (2) heats the cell modules (10), wherein the at least partially flexible carrier plate (2) is guided around the cell modules (10).

Description

The invention relates to a vehicle battery with several cell modules and at least one cell module monitoring device.

The increasing popularity of electric vehicles and hybrid vehicles means that cost-effective and space-saving solutions are being sought for the manufacture of vehicle batteries that at least partially power these vehicles. Vehicle batteries, which are particularly integrated into the traction network of vehicles, usually comprise several cell modules, the battery parameters of which are measured and monitored by at least one cell module monitoring device. Such cell module monitoring devices comprise a large number of components, the installation and construction of which is very complex. In particular, the attachment of resistors and connectors leads to a high installation space requirement. In addition, separate heating systems are installed to ensure that vehicle batteries can deliver satisfactory performance even at low temperatures. But this is also associated with high costs and a large installation space requirement.

From the DE 10 2015 202 601 A1 An accumulator is known in which resistances are provided by means of resistance lines.

Furthermore, the WO 2013/066926 A1 A battery module is known which comprises cell modules. Heating mats are arranged between the cell modules, by means of which the cell modules can be heated.

The DE 10 2017 107 966 A1 describes a cell module with an outer housing in which several battery cells are accommodated. The cell module is covered on the top by a circuit board assembly and a module cover. The circuit board assembly comprises a surface on which an RF communication circuit (wireless radio interface) and a cell detection circuit are arranged. The cell detection circuit is used to measure a respective operating voltage of each of the battery cells. This data is made available to the communication circuit and transmitted wirelessly by it as radio signals to a higher-level controller (master battery controller).

From the DE 10 2011 088 440 A1 An energy storage cell module comprising several energy storage cells is known, in which each individual energy storage cell has its own energy storage monitoring device in addition to an energy storage device. Recorded properties (such as voltage, temperature or pressure) of an energy storage device can be transmitted wirelessly via a communication connection to another communication connection of another energy storage cell. The transmission can be capacitive, inductive or optical. Compensating resistors distributed on a carrier substrate can be used for cell voltage compensation and/or as cell heating.

Finally, the DE 10 2016 210 204 A1 a wiring module for a battery assembly consisting of a plurality of batteries. The wiring module comprises an insulating resin substrate, furthermore connection structures for connection to electrodes of the battery assembly. Voltage detection wiring structures are conductively connected to one another by meander-like fuse structures. An edge region of the connection structures, the voltage detection wiring structures and the fuse structures are covered by an insulating resin layer. A pair of through holes into which the electrodes of the battery assembly are inserted are formed in each connection structure and the insulating resin substrate.

The present invention is based on the object of providing a vehicle battery whose cell modules can be heated in a simple manner.

According to the invention, this object is achieved by a vehicle battery having the features of claim 1. Advantageous embodiments and further developments emerge from the dependent claims.

A cell module monitoring device also disclosed comprises a first component which comprises an evaluation unit and a wireless communication device. Furthermore, the cell module monitoring device comprises an at least partially flexible carrier plate, wherein the at least partially flexible carrier plate has a region in which the first component is arranged.

A flexible carrier plate is understood to mean, in particular, a flexible carrier plate. By arranging the cell module monitoring device on a flexible carrier plate, it is possible in particular to connect the cell module monitoring device in a compact and secure manner to the on-board network wiring, which is also routed via flexible carrier plates. The cell module monitoring device can then be designed together with the wiring to the cell modules as a compact single component. Here This in turn saves installation space and individual parts.

Furthermore, the fact that the cell module monitoring device comprises the first component with the wireless communication device makes it possible to provide wireless communication between the cell module monitoring device and devices in the vehicle. This makes it possible in particular to replace previous plug and/or cable connections of the cell module monitoring device, which are used to connect the cell module monitoring device to devices in the vehicle for data transmission. The arrangement of the wireless communication device therefore advantageously makes it possible to save installation space.

The cell module monitoring device is designed in particular to detect and monitor voltages and temperatures of a cell module. This is done in particular via the evaluation unit, which is designed as a microcontroller, for example. The microcontroller is used in the vehicle battery to control the voltage and temperature monitoring of the cell modules using control signals.

By integrating the evaluation unit with the wireless communication device into the first component, it is possible to dispense with the attachment of many individual parts. This provides a compact design for the cell module monitoring device.

In one embodiment of the cell module monitoring device, the first component is integrated into the area of the at least partially flexible carrier plate. This advantageously allows the design of the cell module monitoring device to be made even more compact.

Furthermore, the area of the at least partially flexible carrier plate in which the first component is arranged can be rigid. The carrier plate which is surrounded by the cell module monitoring device therefore does not have to be completely flexible. The rigid design of the carrier plate in the area in which the first component is arranged can advantageously increase the robustness of the area in which the electronics, which are generally sensitive to environmental influences, are located. In order to ensure a safe and compact design of the cell module monitoring device, the area in which the first component is arranged can be surrounded by a flexible part of the flexible carrier plate.

The rigid design of the area can be achieved in particular by mechanically reinforcing the area. For example, several layers of material can be applied in the area. This strengthens the at least partially flexible carrier plate in the area and makes it rigid. Alternatively, the area can also be made rigid by integrating a conventional circuit board, on which the first component is applied, into the at least partially flexible carrier plate.

The at least partially flexible carrier plate is made in particular from a plastic. The plastic is in particular polyester, polyethylene naphthalate or polyimide. The thickness of the at least partially flexible carrier plate can in particular be in a range from 25 µm to 75 µm.

The at least partially flexible carrier plate can in particular be an FPC film. FPC stands for "flexible printed circuit". The integration of the first component into the FPC film can be achieved, for example, by printing the first component onto the FPC film. This creates a particularly compact cell module monitoring device.

In another embodiment, the wireless communication interface comprises in particular a radio interface for communication with a battery management system, a vehicle bus and/or a user interface. Connection plugs are then no longer required. This advantageously saves installation space. In addition, it is advantageously also possible to dispense with the need to produce soldered connections. Because a soldering process can be dispensed with, no inadequate connections are produced that lead to failures of the cell module.

In a further embodiment, a second and/or third component is arranged in the area, the second component comprising an application-specific integrated circuit and/or the third component comprising a compensation filter. All necessary electronic components of the cell module monitoring device are then advantageously integrated in the area of the at least partially flexible carrier plate. This makes it possible to provide a compact and space-saving design for the cell module monitoring device.

An application-specific integrated circuit, also known as ASIC, is generally understood to be an electronic circuit that is designed as an unchangeable circuit. This means that a once implemented mented function of an ASIC can no longer be changed. The integration of such an ASIC can be implemented in particular in the form of a microchip. In vehicle batteries with central parameter recording, the ASIC is programmed to determine relevant battery parameters required for calculating the current performance of the battery system and to transmit these to a battery management system, which calculates the current performance. In vehicle batteries with decentralized parameter recording, the ASIC can be programmed to determine the current performance relevant for energy management from the various battery parameters recorded. The third component can be designed as a compensation filter, for example. Since individual cell modules of the vehicle battery can differ from one another in terms of their capacity, for example, it can happen that when the vehicle battery is being charged, the cell module with the lowest capacity has reached its final charge voltage, while other cell modules still need to be charged in order to reach their final charge voltage. If the charging process is continued, however, there is a risk that the cell module that has already been fully charged will be damaged by overcharging. If the charging process is interrupted, the vehicle battery cannot reach its optimal charge level. To compensate for these differences, balancing systems are installed in vehicles. These consist of balancing resistors and a balancing filter, which enable controlled discharging of the cell modules.

In another embodiment, the region comprises connection points to which lines for connecting the cell module monitoring device to a cell module can be attached. The lines can in particular also be integrated into the at least partially flexible carrier plate.

The present description also describes a cell module for a vehicle battery with a cell module monitoring device. The cell module is coupled to the cell module monitoring device by means of lines that are arranged on an at least partially flexible carrier plate. The cell module monitoring device can be integrated into the cell module. This means that each cell module of a vehicle battery has its own cell module monitoring device. The parameters of one of the cell modules of a vehicle battery are then recorded decentrally. By communicating with the vehicle's battery management system, the information from the cell module monitoring devices of all cell modules can then be processed centrally. Alternatively, the cell module monitoring device can also be arranged outside the cell module. In this case, in particular, all cell modules of a vehicle battery are coupled to this cell module monitoring device. The parameters of the cell modules are recorded centrally in this case. By arranging a cell module monitoring device in a cell module of a vehicle battery, a compact and space-saving integration of the cell module monitoring device into the cell module can be provided.

As already mentioned, the invention relates to a vehicle battery with several cell modules and at least one cell module monitoring device. Each of the cell modules is coupled to the at least one cell module monitoring device by means of at least one line that is arranged on an at least partially flexible carrier plate. The lines can be attached in particular to the connection points of the cell module monitoring device.

In particular, a cell module monitoring device is arranged for each cell module, wherein each cell module is connected to the cell module monitoring device assigned to it by means of at least one line.

The at least partially flexible carrier plate can then be designed in the area of the cable in particular as a flat conductor foil, in which the cable is printed as a flat track in an FPC foil. This allows the connection of the cell modules to the cell module monitoring device and the connection of the cell modules to one another to be carried out in a compact and space-saving manner.

The line is in particular a resistance line, wherein the resistance that the line provides is determined by means of the material from which the line is made, the line diameter, the line width and/or the line routing on the at least partially flexible carrier plate. This means that physical balancing resistors normally installed in the cell module monitoring device can be replaced by resistance lines. This in turn makes it possible to save installation space and individual parts. Furthermore, the heat produced by the resistance lines can be easily dissipated via the at least partially flexible carrier plate.

The resistance provided by the resistance line can be determined in particular by the material used. The line can in particular be a wire. Possible alloys for the wire preferably contain a high copper content. For example, a copper-nickel, copper-manganese, copper-manganese-tin, copper-nickel-iron-manganese or a copper-nickel-manganese alloy is used. However, the copper-nickel-manganese alloy is preferably used, especially in a composition that results in a constantan alloy. Constantan has an almost constant specific electrical resistance over wide ranges. Because the specific electrical resistance of constantan is independent of temperature, constantan wires are particularly well suited to replacing physical balancing resistors.

Furthermore, the resistance that the cable is to provide can be selected based on the diameter or cross-sectional area of the cable. If a flat conductor foil is used, the resistance of the cable is selected based on the width of the cable. A very small thickness in a range of 10 µm to 50 µm with a length in a range of, for example, 0.05 m to 0.2 m can be achieved. This then results in a resistance for a cable in a range of 0.1 kΩ up to and including 0.5 kΩ.

Furthermore, the resistance that the line is to provide can also be selected by routing the lines in a certain way in the at least partially flexible carrier plate. The line can in particular be routed in a meandering manner through the at least partially flexible carrier plate.

In one implementation of the vehicle battery according to the invention, several lines are arranged evenly distributed over the entire surface of the at least partially flexible carrier plate, so that heat released by the lines is evenly distributed over the at least partially flexible carrier plate, wherein the at least partially flexible carrier plate is arranged near the cell modules in such a way that the at least partially flexible carrier plate heated by means of the lines heats the cell modules. The at least partially flexible carrier plate is guided around the cell modules. This makes it possible for energy from the cell modules to be converted into heat. By controlling the current that is guided through the lines, the heat generated by the lines can be controlled. In this way, the lines can provide heating for the vehicle battery without a separate heating system having to be integrated into the battery. The routing around the cell modules is in particular meander-like. This advantageously leads to each cell module being surrounded by the at least partially flexible carrier plate on at least three sides. The at least partially flexible carrier plate can lie directly against the cell modules. This allows particularly effective heating of the cell modules to be provided.

Furthermore, a fuse can be provided by the line on the at least partially flexible carrier plate. The fuse can be provided in particular by reducing the diameter or width of the line in the area of the fuse compared to the diameter or width of the line when it does not run in the area of the fuse. Furthermore, the routing of the line in the area of the fuse can also be changed. In particular, the line runs in a meandering manner in the fuse area. Such a fuse can advantageously replace conventional fuses, which have to be incorporated into the cell modules using a complex soldering process. The soldering process is therefore initially eliminated. In particular, the soldering process for the fuses can result in an inadequate connection being made between the fuse and the lines. This leads to a failure of the balancing unit of a cell module. This soldering process can be eliminated by arranging the fuses. Therefore, no inadequate connections are made that lead to failures of the balancing unit of the cell module. Furthermore, the separate component of the fuse can be saved. This in turn leads to a reduction in costs and installation space.

• 1 zeigt ein Ausführungsbeispiel für eine Zellmodulüberwachungsvorrichtung,
• 2 zeigt ein Ausführungsbeispiel für die Anordnung einer Zellmodulüberwachungsvorrichtung aus 1 in einer Fahrzeugbatterie in einem Fahrzeug,
• 3 zeigt einen Aufbau eines Zellmoduls und die Verbindung des Zellmoduls mit der Zellmodulüberwachungsvorrichtung,
• 4 zeigt ein erstes Ausführungsbeispiel für die Ausgestaltung von Widerstandsleitungen auf einer flexiblen Trägerplatte,
• 5 zeigt ein zweites Ausführungsbeispiel für die Ausgestaltung von Widerstandsleitungen auf der flexiblen Trägerplatte,
• 6 zeigt eine Anordnung mehrerer Zellmodule und der flexiblen Trägerplatte als Heizsystem in einer Fahrzeugbatterie, und
• 7 zeigt eine Anordnung mehrerer Zellmodule und der flexiblen Trägerplatte in einer Fahrzeugbatterie mit einem Wärmeabtransport aus der Fahrzeugbatterie.

The invention will now be explained using embodiments with reference to the drawings.

• 1 shows an embodiment of a cell module monitoring device,
• 2 shows an embodiment of the arrangement of a cell module monitoring device from 1 in a vehicle battery in a vehicle,
• 3 shows a structure of a cell module and the connection of the cell module with the cell module monitoring device,
• 4 shows a first embodiment for the design of resistance lines on a flexible carrier plate,
• 5 shows a second embodiment for the design of resistance lines on the flexible carrier plate,
• 6 shows an arrangement of several cell modules and the flexible carrier plate as a heating system in a vehicle battery, and
• 7 shows an arrangement of several cell modules and the flexible carrier plate in a vehicle vehicle battery with heat removal from the vehicle battery.

With reference to the 1 and 2 an embodiment of a cell module monitoring device 1 and an arrangement of the cell module monitoring device 1 in a vehicle 15 are explained.

The vehicle 15 is at least partially powered by a vehicle battery 12, which is in particular a traction battery. The vehicle 15 is an electric vehicle or a hybrid vehicle, which is powered partly by the traction battery 12 and partly by an internal combustion engine.

The traction battery 12 comprises, for example, six cell modules 10. Each of the six cell modules 10 has its own cell module monitoring device 1. The parameters of the cell modules 10 are therefore recorded in a decentralized manner.

The cell module monitoring device 1 comprises a first component 4. The first component 4 in turn comprises an evaluation unit 4.1, which is designed as a microcontroller.

Furthermore, the first component 4 comprises a wireless communication device, which is composed of a transceiver 4.2 and an antenna 4.3. The transceiver 4.2 and the antenna 4.3 form a radio interface for communication with a battery management system 17, the vehicle bus 13 and a user interface 14 of the vehicle 15.

The user interface 14 is designed as a display surface on which information about the vehicle battery 12 can be displayed to a user. The display surface 14 receives this information via the radio interface 4.2, 4.3.

Through the radio communication of the cell module monitoring device 1 with the battery management system 17, the information of the cell module 10 can then be processed together with the information of other cell modules 10.

The cell module monitoring device 1 also comprises a second component 5 and a third component 6. The second component 5 is an application-specific integrated circuit, referred to below as ASIC. The third component 4.3 is designed as a balancing filter.

The cell module monitoring device 1 also comprises a flexible carrier plate 2. The flexible carrier plate 2 is made of a plastic, in particular polyester, polyethylene naphthalate or polyimide. The thickness of the flexible carrier plate is in a range from 25 to 75 µm. The flexible carrier plate 2 is in particular an FPC film (FPC = flexible printed circuit).

The FPC film 2 also has an area 3 in which the first 4, second 5 and third component 6 are integrated. The area 3 is designed to be rigid. This ensures that the area 3, which includes sensitive electronic components, can be designed to be robust against environmental influences. The area 3 is made rigid, for example, by mechanical reinforcement. In this case, additional material layers are glued to the FPC film 2 in area 3, which reinforce the area 3. The components 4 to 6 can then be printed on the FPC film 2 in area 3. The FPC film 9 is therefore not completely flexible, but partially flexible.

In another embodiment, however, the region 3 is designed as a conventional circuit board which is integrated into the flexible carrier plate 2 and which comprises the components 4 to 6.

The area 3 also includes connection points 7 to which lines 8 for connecting the cell module monitoring device 1 to a cell module 10 of the vehicle battery 12 can be attached.

The lines 8 are integrated into the FPC film 2 by being printed onto the FPC film 2 as flat tracks. In the area of the lines 8, the FPC film 2 is designed as a so-called flat conductor film 2'.

With reference to 3 an embodiment of a cell module 10 as arranged in the vehicle battery 12 is explained.

The cell module 10 is in particular a cell module 10 with decentralized characteristic value acquisition, into which the cell module monitoring device 1 is integrated. The cell module monitoring device 1 is arranged in particular in a lower region of the cell module 10.

At the connection points 7 of the area 3 of the FPC film 2, lines 8 are attached, which extend upwards into the interior of the cell module 10.

The cell module 10 comprises connecting elements 11 for connecting the cell module 10 to adjacently arranged cell modules 10. The connecting elements 11 are copper rails, which are also integrated on the FPC film 2.

A fuse 9 is also arranged in front of each connecting element 11. The fuse 9 provided is defined in particular by the width of the lines 8 and/or the routing of the lines 8 on the flat conductor foil 2'. The width of the lines 8 in the area of the fuse 9 is smaller than the width of the lines 8 in the areas that do not serve as a fuse 9. Alternatively or additionally, the lines 8 are routed in a meandering manner in the fuse area. This makes it possible to replace conventional fuses that are incorporated into the cell modules 10 using a complex soldering process.

Furthermore, the lines 8 can be designed as resistance lines. This can replace physical balancing resistors, which create a balance between the voltages of individual cell modules 10.

As in 4 shown, each line 8 may have a different width. Alternatively or additionally, the lines 8, as shown in 5 shown, meandering through the flat conductor foil 2'. In particular, the line length resulting from the meandering of the line leads to different resistances.

Furthermore, the material from which the resistance lines 8 are made can determine the resistance of the resistance lines 8. The resistance lines 8 are in particular wires made of constantan.

In another embodiment, the cell module monitoring device 1 is not integrated into the cell module, but is arranged outside the cell module 10. In this case, all cell modules 10 present in the vehicle battery 12 are connected to the cell module monitoring device 1 via the flat conductor foil 2' by means of resistance lines 8.

With reference to the 5 and 6 A heating system for the vehicle battery 12 is explained. The recording of the parameters of the 6 The vehicle battery 12 shown is monitored centrally with only one cell module monitoring device 1.

The resistance lines 8 are evenly distributed over the flat conductor foil 2'. The resistance lines 8 are heated by the current that is passed through them. The heat generated is dissipated via the flat conductor foil 2'.

Compared to cell module monitoring devices 1 with physical resistors, a significantly higher balancing current can be passed through the resistance lines 8, since they can dissipate significantly more heat by transporting the heat away via the flat conductor foil 2'.

This heat can simultaneously be used to heat the cell modules 10 at low temperatures. For this purpose, the flat conductor foil 2' with the evenly distributed resistance lines 8 is guided in a meandering manner around the cell modules 10, as shown in 6 As a result, each cell module 10 can be surrounded by the flat conductor foil 2' on three sides. The heat dissipated by the flat conductor foil 2' can thus be passed on directly to the cell modules 10.

Furthermore, heat that is not passed on to the cell modules 10 can be conducted through a free space from the vehicle battery 12. This is in 7 indicated by arrow 16.

The heating system of the 5 to 7 can also be used in a vehicle battery 12 with decentralized characteristic value recording. For this purpose, the cell modules 10 can then be connected to one another by means of a flat conductor foil 2', which in turn is guided in a meandering manner around the cell modules 10.

Claims (4)

Vehicle battery (12) with a plurality of cell modules (10) and with at least one cell module monitoring device (1), comprising a first component (4) which comprises an evaluation unit (4.1) and a wireless communication device (4.2, 4.3), and an at least partially flexible carrier plate (2), wherein the at least partially flexible carrier plate (2) has a region (3) in which the first component (4) is arranged, wherein each of the cell modules (10) is coupled to the at least one cell module monitoring device (1) by means of at least one line (8) which is arranged on the at least partially flexible carrier plate (2), characterized in that the lines (8) are arranged evenly distributed over the entire surface of the at least partially flexible carrier plate (2), so that heat released by the lines (8) is evenly distributed over the at least partially flexible carrier plate (2), wherein the at least partially flexible carrier plate (2) is arranged near the cell modules (10) in such a way that the at least partially flexible Carrier plate (2) heats the cell modules (10), wherein the at least partially flexible carrier plate (2) is guided around the cell modules (10). Vehicle battery (12) after claim 1 , characterized in that a cell module monitoring device (1) is arranged for each cell module (10), wherein each cell module (10) is connected to the cell module monitoring device assigned to it device (1) by means of at least one line (8). Vehicle battery (12) after claim 1 or 2 , characterized in that the lines (8) are resistance lines, wherein the resistance provided by a line (8) is determined by means of the material from which the lines are made, the line diameter, the line width and/or the line routing on the at least partially flexible carrier plate (2). Vehicle battery (12) according to one of the Claims 1 until 3 , characterized in that the carrier plate (2) is guided in a meandering manner around the cell modules (10).

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