Device for connecting a high-voltage battery to a control unit for the high-voltage battery, a method for operating the device

Abstract

Method and device (100) for connecting a high-voltage battery (101) to a control unit (102) for the high-voltage battery (101), wherein the device (100) comprises inputs (112) for voltage taps (107) between cells of a series connection of battery cells (103) and a trigger cell (104), two of the inputs (112) are assigned to voltage taps (107) between which the trigger cell (104) is arranged, wherein one of the two inputs (112) is electrically unconnected, wherein the other inputs (112) are each electrically connected to an output (116) for the control unit (112), wherein the device (100) comprises a tracking means (124) for providing a battery cell voltage for the trigger cell (104) according to a current state of charge of the high-voltage battery (100), and wherein the device (100) is configured to provide the battery cell voltage at an output (116) for the To provide control unit (112).

Description

[0001] The invention relates to a device for connecting a high-voltage battery to a control unit for the high-voltage battery and a method for operating the device.

[0002] CN 1 17 388 697 A discloses a test system for a thermal diffusion test of a battery pack. The test system comprises a housing. Several test modules are arranged within the housing and include real modules and sham modules. A trigger module is configured to activate a trigger cell to achieve a thermal runaway condition. A power supply unit is connected in series with the real module and provides a substitute voltage. The measuring device is configured to measure at least one parameter representing the thermal diffusion performance of the test system after the trigger cell has been activated.

[0003] EP 2 879 266 A1 discloses an energy management method for a rechargeable energy storage device with stacked battery cells. The state parameters of individual battery cells are monitored. The battery cells can be selectively connected or coupled to a load according to the monitored state parameters of the battery cells. The selective connection of the battery cells to the load is based on a predetermined target voltage for the energy storage device. The battery cells are either continuously monitored or the monitoring is performed only for those battery cells that are currently connected to the load. The state parameters of battery cells that are not currently connected to the load are stored.In this way, the battery cells can be balanced during operation, with individual battery cells being selectively discharged so that the energy storage device is kept in a balanced state at all times.

[0004] To test a battery under realistic conditions, the entire battery system must be modified. For example, a single battery cell is replaced with a trigger cell to generate reproducible results. The characteristics, particularly voltage and capacity, of this trigger cell do not match those of the other battery cells. Therefore, the battery system cannot be tested as a standard production system.

[0005] A device for connecting a high-voltage battery to a control unit for the high-voltage battery provides that the device includes inputs for voltage taps between cells of a series connection of battery cells and a trigger cell in the high-voltage battery, wherein two of the inputs are assigned to voltage taps between which the trigger cell is arranged, wherein one of the two inputs is electrically unconnected, wherein the other inputs are each electrically connected to an output for the control unit, wherein the device includes a tracking means for providing a battery cell voltage for the trigger cell according to a current state of charge of the high-voltage battery, and wherein the device is configured to provide the battery cell voltage at an output for the control unit.

[0006] This device allows for testing of high-voltage batteries with trigger cells at different charge levels. The standard battery management system for a series high-voltage battery (i.e., one battery cell instead of a trigger cell in series) can remain unchanged. The device includes, for example, a measuring device for measuring the current battery cell voltage. This measuring device determines the current battery cell voltage for the corresponding charge level of the high-voltage battery and adjusts the tracking device accordingly. This measurement results in controlled voltage levels and more precise control of the test conditions. This leads to reproducible results when using the trigger cell.

[0007] The device may include additional inputs and outputs.

[0008] For example, the device includes an input for a ground connection of the high-voltage battery and an output for connecting the control unit to ground, wherein the ground connection and the output for connecting the control unit to ground are electrically connected to each other.

[0009] For example, the device includes an input for a connection for the battery voltage of the high-voltage battery and an output for connecting the control unit to the battery voltage, wherein the connection for battery voltage and the output for connecting the control unit to the battery voltage are electrically connected to each other.

[0010] The tracking device may include a variable voltage supply, galvanically isolated from the high-voltage battery and the control unit, to provide the battery cell voltage according to the current state of charge of the high-voltage battery.

[0011] The inputs are, for example, assigned to one of the cells in pairs.

[0012] The inputs for the high-voltage battery and the outputs to the control unit are, for example, arranged on a circuit board.

[0013] For example, the device includes electrical connectors designed to connect the electrically interconnected inputs and outputs.

[0014] For example, the connectors are arranged on the circuit board.

[0015] A method for operating the device when testing the high-voltage battery with the control unit provides that, in particular, a current battery cell voltage is determined for the corresponding state of charge of the high-voltage battery using a measuring device of the device, wherein, in particular, a tracking device of the device is controlled to provide the determined current battery cell voltage for the corresponding state of charge of the high-voltage battery at an output of the device.

[0016] Further exemplary embodiments can be found in the following description and the drawing. The drawing shows: Fig. 1 a schematic representation of a device for connecting a high-voltage battery to a control unit for the high-voltage battery, Fig. 2. A flowchart showing the steps of a procedure for operating the device.

[0017] In Fig. Figure 1 is a schematic representation of a device 100 for connecting a high-voltage battery 101 to a control unit 102.

[0018] The device 100 for connecting high-voltage battery 101 enables realistic testing of the high-voltage battery 101 without functional limitations.

[0019] This will be described below using the example of a simulated thermal incident in the high-voltage battery 101.

[0020] The high-voltage battery 101 comprises battery cells 103 and a trigger cell 104. The trigger cell 104 replaces one of the battery cells 103 of the high-voltage battery 101.

[0021] The trigger cell 101 allows for the generation of reproducible results during testing.

[0022] The testing is not limited to a single trigger cell 104. The high-voltage battery 101 may comprise multiple trigger cells. The device 100 for each trigger cell may be configured as described for the exemplary trigger cell 104.

[0023] The battery cells 103 are series cells, i.e., the battery cells used in the high-voltage battery 101 in series production. The trigger cell 104 does not have the same properties, e.g., voltage or capacity, as the series cells.

[0024] The high-voltage battery 101 includes a ground connection 105 and a voltage connection 106. Battery cells 103 and the trigger cell 104 are arranged in series within the high-voltage battery 101. In this example, the trigger cell 104 is positioned between two battery cells 103. The trigger cell 104 can also be arranged as the first or last cell in the series connection.

[0025] The high-voltage battery 101 includes voltage taps 107 for measuring the voltage of the individual cells. One voltage tap 107 is located at the negative terminal of battery cell 103 connected to the ground terminal 105. Another voltage tap 107 is located at the positive terminal of battery cell 103 connected to the battery voltage terminal 106. The other voltage taps are arranged between the cells in the series connection.

[0026] Device 100 includes an input 108 for ground. The ground input is connected via a connection 109 to the ground terminal 105. Device 100 includes an input 110 for battery voltage. The battery voltage input 110 is connected via a connection 111 to the battery voltage terminal 106.

[0027] The device 100 includes an input 112 for the high-voltage battery 101 for each voltage tap 107. The voltage taps 107 are connected to the respective input 112 for the high-voltage battery 101 via a connection 113.

[0028] Device 100 includes an output 114 for ground. Device 100 includes an output 115 for battery voltage. Device 100 includes an output 116 to control unit 102 for each voltage tap 107.

[0029] Control unit 102 includes an input 117 for ground. Input 117 for ground of control unit 102 is connected to output 114 for ground via connection 118. Control unit 102 includes an input 119 for battery voltage. Input 119 for battery voltage of control unit 102 is connected to output 115 for battery voltage via connection 120.

[0030] The control unit 102 includes an analog-to-digital converter 121 for each voltage tap 107.

[0031] The analog-to-digital converters 121 are connected via a respective connection 122 to each of the outputs 116 to the control unit 102 of the device 100.

[0032] The control unit 102 is designed to measure the voltages of the individual cells of the high-voltage battery 102. The control unit 102 is designed to measure the voltages depending on the signals generated by the analog-to-digital converters 121.

[0033] This would mean that if the high-voltage battery 101 were connected directly to the control unit 102 via the trigger cell 104, i.e. without the device 100, an error would be detected by the trigger cell 104.

[0034] In the example of the simulated thermal incident, the trigger cell 104 would be recognized by the control unit 102 as a missing cell. Therefore, the high-voltage battery 102 cannot be operated with the trigger cell 104 as a series system.

[0035] The device 100 comprises a measuring instrument 123. The measuring instrument 123 is configured to determine the current battery cell voltage corresponding to the state of charge of the high-voltage battery 102. The device 100 also comprises a tracking instrument 124. The tracking instrument 124 is configured to provide the determined current battery cell voltage corresponding to the state of charge of the high-voltage battery 102 instead of the trigger cell 104.

[0036] The tracking device 124 includes, for example, a variable voltage supply that is galvanically isolated from the high-voltage battery 101 and the control unit 102. The voltage supply is designed to provide the battery cell voltage according to the current state of charge of the high-voltage battery 101.

[0037] The device 100 comprises connectors 125 for connecting each of the inputs 112 for the high-voltage battery 101 to each of the outputs 116 to the control unit 102. In this example, the inputs 112 for the high-voltage battery 101 and the outputs 116 to the control unit 102 are arranged on a circuit board 126. The connectors 125 are also arranged on the circuit board 126.

[0038] In Fig. Figure 1 shows an example in which the trigger cell 104 is treated as a missing cell. This means that one of the two voltage taps 107 for measuring the voltage across the trigger cell 104 is connected to the high-voltage battery 101 via the input 112 assigned to this voltage tap 107 and one of the connectors 125 to one of the outputs 116 of the control unit 102. The input 112 assigned to the other of the two voltage taps 107 for the high-voltage battery 101 remains unconnected.

[0039] In the example, the tracking device 124 is connected with its negative terminal to input 112, which is connected to voltage tap 107, located at the positive terminal of battery cell 103, which is connected to the battery voltage terminal 106. In the example, the tracking device 124 is also connected with its positive terminal to output 115 for battery voltage and to output 116 to the control unit 102, which is associated with voltage tap 107, located at the positive terminal of battery cell 103, which is located at the battery voltage terminal 106.

[0040] The other inputs 112 are each connected to one of the other outputs 116 to the control unit 102 via one of the connectors 125.

[0041] The device 100 is not limited to this arrangement of the connectors 125 and the tracking means 124. The connectors 125 and the tracking means 124 can also be arranged between other inputs 112 and outputs 116.

[0042] In Fig. Figure 2 shows a flowchart with steps of a procedure for operating the device 100.

[0043] The procedure includes step 201.

[0044] In step 201, the measuring instrument 123 is used to determine the current battery cell voltage corresponding to the state of charge of the high-voltage battery 101.

[0045] Then step 202 is executed.

[0046] In step 202, the tracking device 124 is controlled to provide the determined current battery cell voltage to the corresponding state of charge of the high-voltage battery 101.

[0047] Optionally, step 203 is then executed.

[0048] In step 203, the high-voltage battery 101 is tested with the control unit 102.

Claims

[1] Device (100) for connecting a high-voltage battery (101) to a control unit (102) for the high-voltage battery (101), characterized by , that the device (100) comprises inputs (112) for voltage taps (107) between cells of a series connection of battery cells (103) and a trigger cell (104) in the high-voltage battery (101), wherein two of the inputs (112) are assigned to voltage taps (107) between which the trigger cell (104) is arranged, wherein one of the two inputs (112) is electrically unconnected, wherein the other inputs (112) are each electrically connected to an output (116) for the control unit (112), wherein the device (100) comprises a tracking means (124) for providing a battery cell voltage for the trigger cell (104) according to a current state of charge of the high-voltage battery (100), and wherein the device (100) is configured to provide the battery cell voltage at an output (116) for the control unit (112). [2] Device (100) according to claim 1, characterized by , that the device (100) includes a measuring instrument (123) for measuring the current battery cell voltage. [3] Device (100) according to any one of the preceding claims, characterized by , that the device comprises an input (108) for a ground connection (105) of the high-voltage battery (101) and an output (114) for connecting the control unit (102) to ground, wherein the ground connection (105) and the output (114) for connecting the control unit (102) to ground are electrically connected to each other. [4] Device (100) according to any one of the preceding claims, characterized by, that the device comprises an input (110) for a connection for battery voltage (106) of the high-voltage battery (101) and an output (115) for connecting the control unit (102) to the battery voltage, wherein the connection for battery voltage (106) and the output (115) for connecting the control unit (102) to the battery voltage are electrically connected to each other. [5] Device (100) according to any one of the preceding claims, characterized by , that the tracking means (124) comprises a variable voltage supply galvanically isolated from the high-voltage battery (101) and the control unit (102) to provide the battery cell voltage according to the current state of charge of the high-voltage battery (101). [6] Device (100) according to any one of the preceding claims, characterized by , that the inputs (112) are each assigned in pairs to one of the cells (103, 104). [7] Device (100) according to any one of the preceding claims, characterized by, that the inputs (112) for the high-voltage battery (101) and the outputs (116) to the control unit (102) are arranged on a circuit board (126). [8] Device (100) according to any one of the preceding claims, characterized by , that the device (100) comprises electrical connectors (125) configured to connect the electrically interconnected inputs (112) and outputs (116). [9] Device (100) according to claims 7 and 8, characterized by that the connectors (125) are arranged on the circuit board (126). [10] Method for operating the device (100) according to one of the preceding claims when testing the high-voltage battery (101) with the control unit (102), characterized by, that, in particular with a measuring means (123) of the device (100), a current battery cell voltage is determined for the corresponding state of charge of the high-voltage battery (101), wherein, in particular, a tracking means (124) of the device (100) is controlled to provide the determined current battery cell voltage for the corresponding state of charge of the high-voltage battery (101) at an output (116) of the device (100).

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