Printed circuit board assembly for monitoring traction battery of a battery electric vehicle

Abstract

The invention relates to a printed circuit board assembly for monitoring a traction battery of a battery-driven vehicle, comprising a plurality of battery cell monitoring circuit boards, wherein each battery cell monitoring circuit board is assigned to a corresponding battery cell group of the traction battery, wherein each battery cell monitoring circuit board comprises a conductor bundle having a plurality of voltage measurement lines for determining a voltage drop across the respective battery cell of the traction battery, and a main circuit board having a plurality of accommodation positions for accommodating the plurality of battery cell monitoring circuit boards, wherein each battery cell monitoring circuit board is mechanically fixed in the corresponding accommodation position of the main circuit board, wherein the main circuit board has a conductor bundle with a plurality of data lines designed for transmitting the voltage drop across the respective battery cell to a battery management system for monitoring a state of charge of the traction battery.

Description

TECHNICAL FIELD

[0001] The present invention relates to the field of battery systems and battery-driven vehicles, in particular electrically driven vehicles. In particular, the present invention relates to a printed circuit board assembly and a method for monitoring traction batteries of battery-driven vehicles. BACKGROUND

[0002] The battery systems currently used for monitoring electric vehicle batteries have a large number of electronic circuit boards or individual components, which are connected to one another via plug-in connectors in order to monitor the individual battery cells of the battery system. For each battery cell group, i.e. a group of battery cells, a CSC ("Cell Supervising Circuit", battery cell monitoring circuit) is assigned, which is implemented on its own printed circuit board or PCB ("Printed Circuit Board"). In the high-performance batteries of current electric vehicles, the battery is composed of a large number of battery cell groups, for which their own CSC is assigned. Connecting these individual CSCs to the battery management system (BMS) via their own cable harnesses quickly leads to a tangle and to wiring errors when the individual modules are manually connected to one another. The assembly of the individual components is also difficult to automate and is usually carried out manually, which means high costs and therefore is disadvantageous for production, in particular in the case of high-power battery systems for driving electric vehicles. SUMMARY

[0003] The technical problem addressed by the present invention is therefore to implement an advantageous design for simplifying and safely assembling a battery system of a traction battery of a battery-driven vehicle, in particular for simplifying the assembly of the individual CSC modules of the battery system, which can advantageously be applied to high-power traction batteries having a large number of battery cells.

[0004] One idea of the present invention is based on automating the contact between the battery cells and the battery cell monitoring circuits (CSC) and thereby simultaneously eliminating cable harnesses and manual assembly processes. This is achieved by connecting the battery cells and by simultaneously integrating a plurality of battery cell monitoring circuits by means of a printed circuit board (hereinafter also referred to as backplane).

[0005] This eliminates the cumbersome, complex and error-prone approach of connecting the battery cells to the monitoring circuits (CSC) via cable harnesses. There is no longer a need for communication between the monitoring circuits via cable harnesses, since communication takes place via the backplane.

[0006] The solution described here can be compatible with existing battery systems. Due to the high degree of automation, it has the advantage of a process-reliable assembly and a low labor input. There are clear cost advantages.

[0007] The technical solution of the present invention is based on integrating a plurality of cell monitoring circuits into one backplane. Formerly independent CSC modules are combined into one central backplane and integrated cell monitoring circuits. This results in a reduction to only one central backplane with integrated cell monitoring circuits or CSCs. Thus, the wiring of the formerly connected CSCs to the battery management system can be omitted. This technical solution is much cheaper to manufacture and is more reliable because potential sources of error can be avoided.

[0008] The technical solution of the present invention also provides the advantage that when using a backplane, on the one hand, a certified CSC developed once can also be used for other projects, so that when using a common component, the costs or expenses and time for component production, development and certification can thus be reduced. On the other hand, due to the size of the backplane, the printed circuit board with electronic components and components cannot be produced in the usual way, i.e. by soldering the components in a reflow oven. However, the backplane itself can be manufactured in the size required for this.

[0009] The present disclosure describes a cell and a cell group or a cell group and a module.

[0010] A cell is an electrical or electrochemical cell, thus an electrochemical energy store and energy converter. During discharge, the stored chemical energy is converted into electrical energy. This energy can be used by a consumer.

[0011] A high-voltage battery consists of a large number of cells. These cells are combined into groups, which are referred to as cell groups in the present disclosure. These cell groups are monitored and balanced by CSCs (cell supervising circuits). The total number of groups gives the voltage of the battery. For example, 96 cell groups x 3.65 V = 350.4 V, which corresponds to a 400 V battery. This voltage multiplied by the number of groups of batteries (e.g. 40) and multiplied by the capacity of the individual cell (e.g. 5 Ah) gives the total capacity of the battery.

[0012] A module or battery module can have a plurality of cell groups. Usually, a housing for a plurality of cells is described as a module. However, these cells do not necessarily have to belong to one group. That is, several groups of cells can be arranged in one module.

[0013] According to a first aspect, the above mentioned technical problem is solved by a printed circuit board assembly for monitoring a traction battery of a battery electric vehicle, wherein the traction battery comprises a plurality of battery cells, which are combined into a plurality of groups of battery cells, wherein the groups of battery cells are combined into one or more groups of battery modules, wherein each battery cell has two battery electrodes, wherein the printed circuit board assembly comprises: a plurality of battery cell monitoring circuit boards, wherein each battery cell monitoring circuit board is assigned to a respective group of battery cells of the plurality of groups of battery cells, wherein each battery cell monitoring circuit board has a wire harness with a plurality of voltage measurement wires, which are connectable to the individual battery electrodes of the battery cells of the respective group of battery cells for measuring the voltage of the individual battery electrodes, and a processor designed to determine a voltage drop over the individual battery cells from the measured voltages of the battery electrodes and to compensate for charging differences of the individual battery cells, and a main circuit board with a plurality of accommodation positions for accommodating the plurality of battery cell monitoring circuit boards, wherein the individual battery cell monitoring circuit boards are mechanically fixed in the respective accommodation position of the main circuit board, wherein each accommodation position is provided with an electrical plug-in connector designed for electrically connecting the processor of the respective battery cell monitoring circuit board with the main circuit board, wherein the main circuit board comprises a wire harness with a plurality of data lines designed for transmitting the voltage drops over the individual battery cells determined by the processors of the battery cell monitoring circuit boards to a battery management system for monitoring the state of charge of the traction battery and for transmitting instructions of the battery management system to the respective processors of the battery cell monitoring circuit boards for balancing the state of charge of the individual battery cells.

[0014] Such a printed circuit board assembly (in the following also referred to as “backplane”) provides the technical advantage of integrating a plurality of separate component groups into one backplane. Thus, the main circuit board and the plurality of battery cell monitoring circuit boards are realized by one common backplane (i.e. the printed circuit board assembly). The formerly separate CSC component groups (i.e. the individual battery cell monitoring circuit boards) are merged into one central backplane. This results in a reduction to only one central backplane (i.e. the printed circuit board assembly), on which the battery cell monitoring tasks of the plurality of battery cell monitoring circuit boards are integrated. The cumbersome wiring of the prior battery cell monitoring assemblies can thus be omitted, no additional wiring is needed anymore. Such a printed circuit board assembly can be produced more cost-effectively and is more reliable compared to assembling the various separate component groups, because potential sources of error during the assembly process can be avoided, since the components are already assembled.

[0015] Another advantage of using a backplane is that a once developed and certified CSC can also be used for other projects, so that common components can be saved and the costs and time for production, development and certification of components can be reduced. On the other hand, due to the size of the backplane, the printed circuit board with the electronic components and components cannot be manufactured in the usual way, i.e. by soldering the components in a reflow oven. However, the printed circuit board assembly itself can be manufactured in the size required for this.

[0016] According to an exemplary embodiment of the printed circuit board assembly, the individual battery cell monitoring circuit boards are pressed into the respective receiving positions of the main circuit board by means of press contacts or are soldered by means of a soldered connection.

[0017] This provides the technical advantage of a fixed mechanical connection, so that the printed circuit board assembly or backplane appears as a single module, in which the wiring of the individual battery cell monitoring circuit boards to the respective battery cell group and the battery management system has already been preconfigured, so that the printed circuit board assembly only needs to be connected to the respective battery module group of the traction battery. This can be done, for example, by inserting it into the respective battery module group during production and can be automated.

[0018] According to an exemplary embodiment of the printed circuit board assembly, the printed circuit board assembly is designed for monitoring one battery module group of one or more battery module groups.

[0019] This provides the technical advantage that a plurality of battery cell groups can be monitored with one printed circuit board assembly, that is to say, a large power traction battery can be monitored with the printed circuit board assembly. If there are more battery cells, a second printed circuit board assembly can be used to monitor the battery cells of a second battery module group.

[0020] According to an exemplary embodiment of the printed circuit board assembly, the individual battery module groups each have a module side along which the battery cell group of the respective battery module group is arranged, wherein the size of the main circuit board corresponds to the size of the module side of the individual battery module groups.

[0021] This provides the technical advantage that the main circuit board can simply be inserted or otherwise connected to the module side of the respective battery module group, thereby simplifying assembly.

[0022] According to an exemplary embodiment of the printed circuit board assembly, the main circuit board comprises a board upper side on which the individual battery cell monitoring circuit boards are fixed, wherein the board upper side is oriented opposite the module side of the respective battery module group.

[0023] This provides the technical advantage that the main circuit board can simply be plugged in on the module side of the corresponding battery module group, so that the individual battery cell monitoring circuit boards are arranged opposite the battery cell groups to be monitored thereby. This leads to a simple and effective structure.

[0024] According to one exemplary embodiment of the printed circuit board assembly, the size and shape of the board-on side of the main circuit board corresponds to the size and shape of the module side of the corresponding battery module group.

[0025] This provides the technical advantage that the individual battery cell monitoring circuit boards are arranged opposite the battery cell groups to which they are correspondingly assigned. This leads to a simple and effective design.

[0026] According to one exemplary embodiment of the printed circuit board assembly, the accommodation positions on the main circuit board for accommodating the plurality of battery cell monitoring circuit boards on the board-on side of the main circuit board are oriented opposite the relevant battery cell groups of the module side of the corresponding battery module group.

[0027] This provides the technical advantage that the battery cell monitoring circuit boards can be easily electrically and mechanically connected to the battery cell groups to which they are correspondingly assigned. Such a connection can already be made automatically during production of the battery system.

[0028] According to one exemplary embodiment of the printed circuit board assembly, a wire harness with a plurality of data lines is printed as a printed conductor group on the main circuit board.

[0029] This provides the technical advantage that the main circuit board can be designed as a printed circuit board (PCB), which can be efficiently manufactured.

[0030] According to one exemplary embodiment of the printed circuit board assembly, the wire harness with a plurality of data lines is constructed on the main circuit board to route a data stream between the processors of the battery cell monitoring circuit boards and the battery management system via the main circuit board.

[0031] This provides the technical advantage that no cables are required to route or forward the data stream. The main circuit board can be designed in such a way that there is no EMC interference. Thus, unnecessary electromagnetic interference radiation can be avoided and the damage to vehicle electrical components by electromagnetic interference radiation can be minimized.

[0032] According to one exemplary embodiment of the printed circuit board assembly, the main circuit board comprises a plug-in connector for a wired electrical connection of the main circuit board to the battery management system.

[0033] This provides the technical advantage that the printed circuit board assembly together with the battery can be placed in different places of the vehicle from the battery management system. Thus, the two systems can be designed independently of each other.

[0034] According to one exemplary embodiment of the printed circuit board assembly, each battery cell monitoring circuit board comprises a wire harness having a plurality of temperature measuring wires which are connectable to the respective temperature sensors of the battery cells of the respective battery cell group for detecting a temperature sensor value of the respective battery cell, wherein the processor of the respective battery cell monitoring circuit board is designed to determine a temperature of the respective battery cell from the detected temperature sensor value and to transmit it to the battery management system via the wire harness of the main circuit board.

[0035] This provides the technical advantage that the printed circuit board assembly can perform temperature monitoring of the battery cells in addition to state of charge monitoring.

[0036] According to a second aspect, the above technical problem is solved by a battery system of a battery electric vehicle, wherein the battery system comprises: a traction battery of the battery electric vehicle having a plurality of battery cells, the plurality of battery cells being combined into a plurality of battery cell groups, wherein the battery cell groups are combined into one or more battery module groups, wherein each battery cell has two battery electrodes; and a printed circuit board assembly according to the above described first aspect for monitoring the traction battery.

[0037] This means that the cumbersome, complex and error-prone process of connecting the battery cells with the battery cell monitoring circuit boards or CSCs via a cable harness can be dispensed with. There is no longer a need for communication between the monitoring circuits via a cable harness, since the communication takes place via the backplane or the printed circuit board assembly.

[0038] According to one exemplary embodiment of the battery system, the printed circuit board assembly is designed for monitoring one of the one or more battery module groups.

[0039] This provides the technical advantage that the battery system can be monitored with one printed circuit board assembly with a plurality of battery cells, that is to say, the battery system can be equipped with a high-power traction battery having a plurality of battery cells.

[0040] According to one exemplary embodiment of the battery system, the printed circuit board assembly is arranged opposite the battery module group to be monitored.

[0041] This provides the technical advantage that the main circuit board can be simply plugged onto the battery module group to be monitored or connected in another way, which simplifies assembly.

[0042] According to one exemplary embodiment of the battery system, the main circuit board of the printed circuit board assembly is mounted on the battery module group to be monitored and electrically connects the battery electrodes of the respective battery group with the wire harness of the respective battery cell monitoring circuit board.

[0043] This provides the technical advantage that the battery cell monitoring circuit boards can easily be electrically and mechanically connected with the battery cell groups to which they are assigned. Such connections can already be made automatically during the production of the battery system. Thereby, a source of errors that could occur in the manual wiring of individual printed circuit boards or CSC modules is eliminated. The safety of the battery system is thereby also improved.

[0044] According to a third aspect, the above mentioned technical problem is solved by a method for monitoring a traction battery of a battery electric vehicle having a printed circuit board assembly according to the above mentioned first aspect, wherein the traction battery comprises a plurality of battery cells combined into a plurality of battery cell groups, wherein the battery cell groups are combined into one or more battery module groups, wherein each battery cell has two battery electrodes, wherein the method comprises: detecting a voltage of each battery electrode of each battery cell by means of the voltage measurement lines of the respective battery cell monitoring circuit board; determining a voltage drop over each battery cell from the detected voltage of each battery electrode; transmitting the voltage drop over each battery cell to a battery management system by means of the wire bundle of the main circuit board for monitoring a state of charge of the traction battery; and receiving instructions of the battery management system to each processor of the battery cell monitoring circuit board for balancing the state of charge of each battery cell.

[0045] Such a method has the same advantages as the above mentioned printed circuit board assembly. That is, compared to assembling various individual component groups, the printed circuit board assembly can be more cost efficient and more reliable, because potential sources of errors during the assembly process can be avoided since the components are already assembled. Thus, using such a printed circuit board assembly, the method can be performed more reliably.

[0046] According to a fourth aspect, the above mentioned technical problem is solved by a computer program comprising program code for executing the method according to the third aspect on a computer.

[0047] This realizes a technical advantage that the computer program can easily be executed on a control device like a microcontroller. BRIEF DESCRIPTION OF DRAWINGS

[0048] The application will be described in more detail with reference to embodiments and to the attached drawings. In which:

[0049] Figure 1a a schematic diagram of a battery system 100 of a battery electric vehicle according to an embodiment is shown;

[0050] Figure 1b a schematic diagram of a backplane 110 of a battery system 100 of a battery electric vehicle according to an embodiment is shown;

[0051] Figure 2a schematic diagram showing a portion of the back plate 110 of the battery system 100 of a battery driven vehicle, according to one embodiment; and

[0052] Figure 3 a schematic diagram showing a portion of the back plate 110 of the battery system 100 of a battery driven vehicle, according to one embodiment; and

[0053] Figure 4 a schematic diagram showing a method for monitoring a battery driven vehicle, according to one embodiment.

[0054] The figures are merely schematic representations, and are included only to facilitate explanation of the present application. Elements having the same or similar function are designated with the same reference numerals throughout. DETAILED DESCRIPTION

[0055] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which are shown by way of illustration specific embodiments in which the application can be practiced. It is understood that other embodiments can be utilized and structural or logical changes can be made without departing from the scope of the present application. Therefore, the following detailed description is not to be taken in a limiting sense, as the scope of the embodiments are defined by the appended claims and equivalents thereof. It is to be understood that features of the various embodiments described herein can be combined with each other, unless specifically noted otherwise.

[0056] These aspects and embodiments will be described with reference to the accompanying drawings, wherein like reference numerals generally indicate corresponding elements throughout the various figures. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more aspects or embodiments. It can be evident, however, that one or more aspects or embodiments can be practiced without using all the specific details. In other instances, well-known structures and elements are shown in block diagram form in order to facilitate describing one or more aspects or embodiments. It should be noted that one or more aspects or embodiments can be practiced using other structures and elements, and that the specific details given are not to be interpreted as limiting.

[0057] A printed circuit board assembly and a printed circuit board or circuit board is described. In the sense of the present application, such a printed circuit board assembly is a fixed arrangement of different printed circuit boards or circuit boards, which are firmly connected to each other, so that the work of plugging in the individual components by means of plugs or cables can be dispensed with. The printed circuit board assembly can thus be produced easily by means of a machine and can be manufactured in advance. The individual printed circuit boards and circuit boards can be connected to each other by means of various connection techniques, for example by means of soldering, welding, adhesion, gluing or other techniques, for example.

[0058] Circuit boards or printed circuit boards, PCBs, are carriers for electronic components. Printed circuit boards are used for mechanical fastening and electrical connection. Printed circuit boards consist of an electrically insulating material and electrically conductive connections adhered thereto, i.e. a printed conductor group. Fibre-reinforced plastic is usually used as the insulating material.

[0059] A battery cell monitoring circuit board is described. This circuit board is used for battery cell monitoring and comprises a battery cell monitoring circuit (CSC). The battery cell monitoring circuit CSC is an electronic circuit which is used to ensure an even state of charge of individual battery cell groups or battery packs of a battery driving a vehicle.

[0060] Due to various mechanisms, for example manufacturing tolerances of the battery or similar, repeated charging and discharging leads to different states of charge of the battery packs. The battery pack with the highest state of charge determines the maximum charging cut-off time of the entire battery (battery "full"); the battery pack with the lowest state of charge determines the minimum discharging cut-off time (battery "empty"). The greater the state difference, the lower the available capacity of the battery. In the "worst case", the capacity is zero, although the battery is not "worn out / broken".

[0061] In order to avoid these disadvantages described here, the state of charge of all battery packs is monitored to its most important characteristic value when charging the traction battery. This function is carried out by the battery cell monitoring circuit. If individual charging curves deviate, the charging parameters of the corresponding battery pack are also changed or balanced accordingly. This ensures that after the charging process is complete, all battery packs have the same state of charge.

[0062] The state of charge ("State of Charge", SoC) is a characteristic value of the state of charge of a battery. The state of charge indicates the available capacity of the battery in relation to the rated value, usually expressed in percent of the fully charged state. Thus, 10% means that the battery or accumulator still has 10% of the total amount of electricity compared to 100% of the full amount of electricity.

[0063] The individual battery cell monitoring circuit of a battery cell group is controlled by a battery management system (BMS), which communicates with the main control via the vehicle bus.

[0064] The BMS comprises an electronic control circuit for monitoring and controlling the charging and discharging of the vehicle battery. The battery parameters to be monitored include, for example, the battery type, the battery voltage, the temperature and voltage of the individual battery cells, the battery capacity, the state of charge, the current consumption, the remaining operating time, the charging cycle and the detection of other battery parameters.

[0065] The task of the BMS is to ensure that the remaining energy available in the battery is used optimally. To prevent damage to the battery, the BMS protects the battery from deep discharges, overvoltage, too fast charging and too large discharging currents. In a battery consisting of multiple battery cells, the BMS is used for battery balancing, i.e. for making the different battery cells have the same state of charge and state of discharge.

[0066] The communication of the battery management system with other connected units, like the CSC, can be done through a serial interface, like the I2C bus or the CAN bus.

[0067] Figure 1a A schematic view of a battery system 100 of a battery driven vehicle is shown, according to an embodiment, Figure 1b A schematic view of a backplane 110 of a battery system 100 of a battery driven vehicle is shown, according to an embodiment.

[0068] The battery system 100 comprises a printed circuit board assembly 110 and a battery or high voltage battery or traction battery 140 of a battery driven vehicle.

[0069] The traction battery 140 comprises a plurality of battery cells, which are combined into a plurality of battery cell groups 130. The battery cell groups 130 are combined into one or more battery module groups 141. Figure 1a Some 5 by 18 battery cell groups 130 are exemplarily shown, which are combined into one battery module group 141 or module and monitored by the printed circuit board assembly 110.

[0070] Each battery cell 131a, 131b, 131c, 131d has two battery electrodes 132, 133, like Figure 2 is shown in more detail.

[0071] The printed circuit board assembly 110 is used for monitoring the traction battery 140 of a battery driven vehicle. The printed circuit board assembly 110 comprises a plurality of battery cell monitoring circuit boards 120 and a main circuit board 160.

[0072] Each battery cell monitoring circuit board 120 is assigned to a respective one of the plurality of battery cell groups 130. Each battery cell monitoring circuit board 120 comprises a wire harness 121 having a plurality of voltage measurement wires, which are connectable to the individual battery electrodes 132, 133 of the battery cells 131a, 131b, 131c, 131d of the respective battery cell group 130 for detecting the voltage of the individual battery electrodes, like Figure 2 is shown.

[0073] Each battery cell monitoring circuit board 120 comprises a processor 122 designed to determine a voltage drop 134 over the respective battery cell 131a from a detected voltage of the battery electrode and to compensate for differences in the charge of the respective battery cells 131a, 131b, 131c, 131d, as shown in Figure 2

[0074] The main circuit board 160 comprises a plurality of accommodation positions 123, as shown in Figure 3 in more detail, for accommodating a plurality of battery cell monitoring circuit boards 120, wherein each battery cell monitoring circuit board 120 is mechanically fixed 302 in a respective accommodation position 123 of the main circuit board 160.

[0075] Each accommodation position 123 has an electrical plug-in connector 301 designed to electrically connect the processor 122 of the respective battery cell monitoring circuit board 120 with the main circuit board 160.

[0076] The main circuit board 160 has a wire harness 113 with a plurality of data lines designed to transmit the voltage drops 134 over the respective battery cells 131a, 131b, 131c, 131d determined by the processors 122 of the battery cell monitoring circuit boards 120 to the battery management system 150 for monitoring the state of charge of the traction battery 140 and to transmit instructions of the battery management system 150 to the respective processors 122 of the battery cell monitoring circuit boards 120 for balancing the state of charge of the battery cells.

[0077] Each battery cell monitoring circuit board 120 can be press-fitted (e.g. by press contacts 302) into the respective accommodation position 123 of the main circuit board 160, as shown in Figure 3 or welded with a soldered connection. In one embodiment, the press contacts 302 can be released again in order to, for example, replace a defective battery cell monitoring circuit board 120 or to change the configuration of the battery cell monitoring circuit boards 120.

[0078] The printed circuit board assembly 110 can be designed for monitoring one battery module group 141 of one or more battery module groups 141.

[0079] The battery module groups 141 each comprise a module side 142 along which the battery cell groups 130 of the respective battery module group 141 can be arranged. The size of the main circuit board 160 can correspond to the size of the module side 142 of the respective battery module group 141.

[0080] ​The main circuit board 160 comprises a board upper side 161 on which each battery cell monitoring circuit board 120 is fixed. The board upper side 161 can be oriented opposite to the module side 142 of the corresponding battery module group 141. In this case, the battery cell monitoring circuit board 120 is arranged directly opposite (or behind Figure 1a corresponding battery cell group 130, such that long wires do not need to be provided for detecting sensor data of the battery cell group 130.

[0081] The size and shape of the board upper side 161 of the main circuit board 160 can correspond to the size and shape of the module side 142 of the corresponding battery module group 141.

[0082] The receiving positions 123 on the board upper side 161 of the main circuit board 160 for receiving the plurality of battery cell monitoring circuit boards 120 can be oriented opposite to the associated battery cell group 130 on the module side 142 of the corresponding battery module group 141, as shown in Figure 1a corresponding battery cell group 130, such that long wires do not need to be provided for detecting sensor data of the battery cell group 130.

[0083] For example, the wire harness 113 with the plurality of data lines can be pre-printed as a printed wire group on the main circuit board 160. This pre-printing of the main printed circuit board 160 eliminates the otherwise necessary wiring needs for the respective battery cell monitoring circuit boards 120, thus providing for an easier and safe installation.

[0084] The wire harness 113 with the plurality of data lines on the main circuit board 160 can be designed to route or forward data streams between the processor 122 of the battery cell monitoring circuit board 120 and the battery management system 150 through the main circuit board 160.

[0085] The main circuit board 160 can comprise a plug-in connector 301 for wired electrical connection of the main circuit board 160 with the battery management system 150.

[0086] The battery system 100 can be installed in a battery compartment of a vehicle, while the BMS 150 can be installed in a control box located at different locations of the vehicle. For electrical connection, a cable can be used, which can be part of a wire harness or cable harness in the vehicle.

[0087] Each battery cell monitoring circuit board 120 can further comprise a wire harness with a plurality of temperature measurement wires, which can be connected to the respective temperature sensors of the battery cells 131a, 131b, 131c, 131d of the corresponding battery cell group 130 for detecting the temperature sensor values of the individual battery cells.

[0088] To this end, the processor 122 of the battery cell monitoring circuit board 120 can be designed to determine the temperature of the respective battery cell 131a, 131b, 131c, 131d from the detected temperature sensor value and to transmit the temperature sensor value to the battery management system 150 via the wire harness 113 of the main circuit board 160.

[0089] As mentioned above, the battery system 100 comprises a traction battery 140 and a printed circuit board assembly 110 for monitoring the traction battery 140. The printed circuit board assembly 110 can be designed for monitoring one battery module group 141 of one or more battery module groups 141. As Figure 1a shown, the printed circuit board assembly 110 can be arranged opposite the battery module group 141 to be monitored.

[0090] The main circuit board 160 of the printed circuit board assembly 110 can be mounted (e.g. plugged or soldered or welded or glued) on the battery module group 141 to be monitored and electrically connects the respective battery electrodes 132, 133 of the battery cells 131a, 131b, 131c, 131d of the respective battery cell group 130 with the wire harness 121 of the respective battery cell monitoring circuit board 120.

[0091] Figure 2 A schematic diagram of a battery cell monitoring circuit board 120 of a battery system 100 for a battery-driven vehicle according to one embodiment is shown.

[0092] As Figure 1a and Figure 1b shown, the battery cell monitoring circuit board 120 is associated with a respective battery cell group 130 of a plurality of battery cell groups 130. The battery cell monitoring circuit board 120 comprises a wire harness 121 having a plurality of voltage measurement wires connectable to the respective battery electrodes 132, 133 of the battery cells 131a, 131b, 131c, 131d of the respective battery cell group 130 to detect the voltage of the respective battery electrode.

[0093] The battery cell monitoring circuit board 120 comprises a processor 122 designed to determine the voltage drop 134 over the respective battery cell 131a from the detected voltage of the battery electrodes 132, 133 and to compensate for differences in the state of charge of the respective battery cells 131a, 131b, 131c, 131d.

[0094] Figure 3 A schematic diagram of a portion of a back plate 110 of a battery system 100 for a battery-driven vehicle according to one embodiment is shown.

[0095] As mentioned above with regard to Figure 1a , Figure 1b and Figure 2The backplane 110 or printed circuit board assembly 110 is used for monitoring a traction battery 140 of a battery-driven vehicle. The printed circuit board assembly 110 comprises a plurality of battery cell monitoring circuit boards 120 (two of which are exemplarily shown here) and a main circuit board 160.

[0096] As shown in Figure 1a , Figure 1b and Figure 2 each battery cell monitoring circuit board 120 is assigned to a respective one of a plurality of battery cell groups 130.

[0097] The main circuit board 160 comprises a plurality of accommodation positions 123 for receiving the plurality of battery cell monitoring circuit boards 120, wherein each battery cell monitoring circuit board 120 is mechanically fixed 302 in a respective accommodation position 123 of the main circuit board 160. This can be done, for example, by means of press contacts 302 as shown in Figure 3 Alternatively, the fixing can also be done by means of soldering connections, or welding or gluing.

[0098] As shown in Figure 3 each accommodation position 123 can be provided with an electrical plug-in connector 301 designed to electrically connect a processor 122 of a respective battery cell monitoring circuit board 120 with the main circuit board 160. Figure 3 The two battery cell monitoring circuit boards 120 in are arranged rotated by 180° relative to each other. The electrical plug-in connectors 301 are visible in the upper battery cell monitoring circuit board 120, while the press contacts 302 are visible in the lower battery cell monitoring circuit board 120.

[0099] Each battery cell monitoring printed circuit board 120 can be press-fitted (for example, by means of press contacts 302) or soldered by means of soldering connections into a respective accommodation position 123 of the main circuit board 160. In one embodiment, the press contacts 302 can also be released again in order to, for example, replace a defective battery cell monitoring circuit board 120 or to change the configuration of the battery cell monitoring circuit boards 120.

[0100] The printed circuit board assembly 110 can be designed for monitoring one of a plurality of battery module groups 141.

[0101] Figure 4 A schematic diagram of a method 400 for monitoring a battery-driven vehicle according to one embodiment is shown.

[0102] The method is for monitoring a battery-driven vehicle having a traction battery 140 as described above with respect to Figs. 1 to Figure 3The printed circuit board assembly 110 is a traction battery of a battery driven vehicle, wherein the traction battery comprises a plurality of battery cells, which are combined into a plurality of battery cell groups, wherein the battery cell groups are combined into one or more battery module groups, wherein each battery cell has two battery electrodes.

[0103] The method 400 comprises detecting 401 the voltage of each battery electrode of a battery cell using the voltage measurement wires of the battery cell monitoring circuit board, as described above in relation to Figures 1 to 3. Figure 3

[0104] The method 400 comprises determining the voltage drop over each battery cell from the detected voltage of each battery electrode, as described above in relation to Figures 1 to 3.

[0105] The method 400 comprises transmitting the voltage drop over each battery cell to the battery management system via the wire harness of the main circuit board for monitoring the state of charge of the traction battery, as described above in relation to Figures 1 to 3. Figure 3

[0106] The method 400 comprises receiving instructions from the battery management system to each processor of the battery cell monitoring circuit board to balance the state of charge of each battery cell, as described above in relation to Figures 1 to 3. Figure 3

[0107] The method can be implemented on a processor, for example a processor of the battery cell monitoring circuit board, as described above in relation to Figures 1 to 3. Figure 3

[0108] List of reference signs

[0109] 100 battery system

[0110] 110 printed circuit board assembly

[0111] 113 wire harness with a plurality of data lines

[0112] 114 electrical plug connector to BMS

[0113] 120 battery cell monitoring circuit board

[0114] 121 wire harness with a plurality of voltage measurement wires

[0115] 122 processor

[0116] 123 accommodation location of main circuit board

[0117] 130 battery cell group

[0118] 131a first battery cell

[0119] ​​​​131b second battery cell

[0120] 131c third battery cell

[0121] 131d fourth battery cell

[0122] 132 first pole or positive pole of the battery cell

[0123] 133 second pole or negative pole of the battery cell

[0124] 134 voltage drop over the battery cell

[0125] 140 traction battery or battery

[0126] 141 battery module group or module

[0127] 142 module side of the battery module group

[0128] 150 battery management system

[0129] 160 main circuit board

[0130] 161 on-board side of the main circuit board

[0131] 301 electrical plug-in connector

[0132] 302 mechanical fixing, pressing-on of the battery cell monitoring circuit board 120 on the main circuit board 160

[0133] 400 method for monitoring a traction battery

[0134] 401 first method step

[0135] 402 second method step

[0136] 403 third method step

[0137] 404 fourth method step

Claims

1. A printed circuit board assembly (110) for monitoring a traction battery (140) of a battery-powered vehicle, wherein, The traction battery (140) includes multiple battery cells (131a, 131b, 131c, 131d), which are combined into multiple battery cell groups (130). The battery cell groups (130) are further combined into one or more battery module groups (141). Each battery cell has two battery electrodes (132, 133). The printed circuit board assembly (110) includes: Multiple battery cell monitoring circuit boards (120), wherein each battery cell monitoring circuit board (120) is configured for a corresponding battery cell group (130) among multiple battery cell groups (130), wherein each battery cell monitoring circuit board (120) has a wire harness (121) with multiple voltage measuring wires that can be connected to the respective battery electrodes (132, 133) of the battery cells (131a, 131b, 131c, 131d) of the corresponding battery cell group (130) for detecting the voltage of the respective battery electrodes; and a processor (122) designed to determine the voltage drop (134) on each battery cell (131a) based on the detected voltage of the battery electrodes and to compensate for the charging differences of the battery cells (131a, 131b, 131c, 131d); and The main circuit board (160) has multiple receiving positions (123) for receiving multiple battery cell monitoring circuit boards (120), wherein each battery cell monitoring circuit board (120) is mechanically fixed (302) in a corresponding receiving position (123) of the main circuit board (160), wherein each receiving position (123) is provided with an electrical connector (301) designed for electrically connecting the processor (122) of the corresponding battery cell monitoring circuit board (120) to the main circuit board (160), wherein the main circuit board ( 160) includes a wire harness (113) with multiple data lines, the wire harness being designed to transmit voltage drops (134) at each battery cell (131a, 131b, 131c, 131d) determined by the processor (122) of the battery cell monitoring circuit board (120) to the battery management system (150) to monitor the state of charge of the traction battery (140), and to transmit instructions to the corresponding processor (122) of the battery monitoring circuit board (120) to the battery management system (150) to balance the state of charge of each battery cell.

2. The printed circuit board assembly (110) according to claim 1, in, Each battery cell monitoring circuit board (120) is pressed into the corresponding receiving position (123) of the main circuit board (160) by pressing the contact (302) or by soldering.

3. The printed circuit board assembly (110) according to claim 1 or 2, in, The printed circuit board assembly (110) is designed to monitor one of the battery module groups (141) in one or more battery module groups (141).

4. The printed circuit board assembly (110) according to claim 1 or 2, in, The battery module group (141) each has a module side (142), and the battery cell group (130) of the corresponding battery module group (141) is arranged along the module side. The size of the main circuit board (160) corresponds to the size of the module side (142) of each battery module group (141).

5. The printed circuit board assembly (110) according to claim 4, in, The main circuit board (160) includes an upper side (161) on the board, and each battery cell monitoring circuit board (120) is fixed on the upper side of the board. The upper side (161) of the plate is oriented to face the module side (142) of the corresponding battery module group (141).

6. The printed circuit board assembly (110) according to claim 5, in, The size and shape of the upper side (161) of the main circuit board (160) correspond to the size and shape of the module side (142) of the corresponding battery module group (141).

7. The printed circuit board assembly (110) according to claim 5 or 6, in, The receiving position (123) of the main circuit board (160) is oriented to accommodate multiple battery cell monitoring circuit boards (120) on the upper side (161) of the main circuit board (160) and to be opposite to the corresponding battery cell group (130) on the module side (142) of the corresponding battery module group (141).

8. The printed circuit board assembly (110) according to claim 1 or 2, in, A wire bundle with multiple data lines is printed as a printed conductor group on the main circuit board.

9. The printed circuit board assembly (110) according to claim 8, in, A wire harness (113) with multiple data lines is constructed on the main circuit board (160) to route data flow between the processor (122) of the battery cell monitoring circuit board (120) and the battery management system (150) via the main circuit board (160).

10. The printed circuit board assembly (110) according to claim 1 or 2, in, The main circuit board (160) includes a plug connector (301) for wired electrical connection between the main circuit board (160) and the battery management system (150).

11. The printed circuit board assembly (110) according to claim 1 or 2, in, Each battery cell monitoring circuit board (120) includes a wiring harness having multiple temperature measuring wires that can be connected to the respective temperature sensors of the battery cells (131a, 131b, 131c, 131d) in the corresponding battery cell group (130) for detecting the temperature sensor values ​​of each battery cell. The processor (122) of each battery cell monitoring circuit board (120) is designed to determine the temperature of each battery cell (131a, 131b, 131c, 131d) based on the detected temperature sensor values, and transmit the temperature to the battery management system (150) via the wire harness (113) of the main circuit board (160).

12. A battery system (100) for a battery-powered vehicle, the battery system (100) comprising: A traction battery (140) for a battery-powered vehicle includes multiple battery cells (131a, 131b, 131c, 131d), said battery cells being combined into multiple battery cell groups (130), wherein the battery cell groups (130) are combined into one or more battery module groups (141), wherein each battery cell (131a, 131b, 131c, 131d) has two battery electrodes (132, 133); and Printed circuit board assembly (110) for monitoring traction battery (140) according to any one of claims 1 to 11.

13. The battery system (100) according to claim 12, in, The printed circuit board assembly (110) is designed to monitor one of the battery module groups (141) in one or more battery module groups (141).

14. The battery system (100) according to claim 13, in, The printed circuit board assembly (110) is arranged opposite the battery module group (130) to be monitored.

15. The battery system (100) according to claim 13 or 14, in, The main circuit board (160) of the printed circuit board assembly (110) is mounted on the battery module group (130) to be monitored, and the battery electrodes (132, 133) of the battery cells (131a, 131b, 131c, 131d) of the corresponding battery cell group (130) are electrically connected to the wire harness (121) of the monitoring circuit board (120) of each battery cell.

16. A method (400) for monitoring the traction battery of a battery-driven vehicle having a printed circuit board assembly (110) according to any one of claims 1 to 11, wherein, The traction battery includes multiple battery cells, which are combined into multiple battery cell groups, wherein the battery cell groups are combined into one or more battery module groups, wherein each battery cell has two battery electrodes, and the method includes: The voltage of each battery electrode in the battery cell is detected by the voltage measurement wires on the monitoring circuit board of each battery cell (401). The voltage drop across each battery cell is determined based on the detected voltage at each battery electrode (402). The voltage drop of each battery cell is transmitted to the battery management system via the wiring harness on the main circuit board to monitor the charging status of the traction battery; and Receive (404) instructions from the battery management system to each processor on the battery cell monitoring circuit board to balance the charging state of each battery cell.

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