Diagnosing and locating battery pack faults

Abstract

And battery pack faults are diagnosed and positioned. A vehicle system includes a battery pack including a plurality of battery cells, a voltage sensor configured to sense an output voltage of the plurality of battery cells, and a control module in communication with the voltage sensor. The control module is configured to detect a fault associated with the battery pack, receive a first voltage signal representative of a first voltage value and a second voltage signal representative of a second voltage value from the voltage sensor, determine a defined ratio of the first voltage value and the second voltage value, and determine a fault associated with the battery pack based on the defined ratio and a total number of the plurality of battery cells in the battery pack. A cell location of the detected fault in the battery pack is determined, and an alert indicative of the cell location of the detected fault is generated. Other example vehicle systems and methods are also disclosed.

Description

[0001] The information provided in this section is for the purpose of generally presenting the context of this disclosure. The work of the inventors currently named herein, to the extent it is described in this section, and aspects of this description that may otherwise not qualify as prior art at the time of filing, are neither expressly nor implicitly acknowledged as prior art to this disclosure. Technical Field

[0002] This disclosure relates to diagnosing and locating battery pack faults, and more particularly to diagnosing and locating battery pack faults in a vehicle's rechargeable energy storage system. Background Technology

[0003] Electric vehicles, such as battery electric vehicles, hybrid vehicles, and / or fuel cell vehicles, include one or more motors and battery systems, the battery system having one or more battery cells, battery modules, and / or battery packs. For example, the battery system may be a rechargeable energy storage system comprising one or more high-voltage battery packs, each high-voltage battery pack having an assembly of battery cells. Typically, one or more battery packs in a rechargeable energy storage system are electrically isolated from components outside the battery pack. Summary of the Invention

[0004] A vehicle system for detecting faults in a battery pack includes: a battery pack comprising multiple battery cells; a voltage sensor configured to sense the output voltage of the multiple battery cells; and a control module communicating with the voltage sensor. The control module is configured to detect faults associated with the battery pack; receive from the voltage sensor a first voltage signal representing a first voltage value and a second voltage signal representing a second voltage value; determine a defined ratio between the first voltage value and the second voltage value; determine the location of the detected fault within the battery cell in the battery pack based on the defined ratio and the total number of the multiple battery cells in the battery pack; and generate an alarm indicating the location of the detected fault within the battery cell.

[0005] Among the other features, the first voltage value is the negative center voltage of the battery pack, and the second voltage value is the positive center voltage of the battery pack.

[0006] Among other features, the control module is configured to determine the slopes of a first voltage signal and a second voltage signal, and in response to a slope being less than or equal to a defined threshold, to measure the negative center voltage of the battery pack from the first voltage signal and the positive center voltage of the battery pack from the second voltage signal.

[0007] Among other features, the control module is configured to determine the defined ratio of the first voltage value and the second voltage value by dividing the negative center voltage by the sum of the negative center voltage and the positive center voltage.

[0008] Among other features, the control module is configured to determine the location of battery cells by multiplying a defined ratio by the total number of battery cells in the battery pack.

[0009] Among other features, the battery pack includes cell groups, each of which comprises a different set of battery cells.

[0010] Among other features, the control module is configured to determine the defined ratio of the first voltage value and the second voltage value by summing the cell group voltages of the selected quantity's cell group and dividing the total cell group voltage by the sum of the negative and positive center voltages.

[0011] Among other features, the selection of cell groups is determined based on the negative intermediate voltage.

[0012] Among other features, the control module is configured to determine the location of battery cells by multiplying a defined ratio by the total number of battery cells in the battery pack.

[0013] Among other features, the voltage sensor includes a voltage divider with multiple resistors, the vehicle system further includes a switching device coupled to the voltage divider, and the control module is configured to control the switching device to connect a collection of different resistors in the voltage divider.

[0014] Among other features, the battery cell location is a first battery cell location, and the control module is configured to determine, after determining the first battery cell location, a second battery cell location in the battery pack for the detected fault, and to identify the type of fault associated with the battery pack based on the first and second battery cell locations.

[0015] Among other features, the control module is configured to determine whether the first battery cell location and the second battery cell location are the same, and in response to the first battery cell location and the second battery cell location being the same, to identify the type of fault associated with the battery pack as a first type of fault, and in response to the first battery cell location and the second battery cell location being different, to identify the type of fault associated with the battery pack as a second type of fault.

[0016] A method for detecting a fault in a battery pack comprising multiple battery cells includes detecting a fault associated with the battery pack; receiving a first voltage signal representing a first voltage value of the battery pack and a second voltage signal representing a second voltage value of the battery pack from a voltage sensor; determining a defined ratio of the first voltage value and the second voltage value; determining the location of the detected fault in a battery cell within the battery pack based on the defined ratio and the total number of the multiple battery cells in the battery pack; and generating an alarm indicating the location of the detected fault in a battery cell.

[0017] Among the other features, the first voltage value is the negative center voltage of the battery pack, and the second voltage value is the positive center voltage of the battery pack.

[0018] Among other features, the method further includes determining the slopes of a first voltage signal and a second voltage signal, and measuring the negative center voltage of the battery pack from the first voltage signal and the positive center voltage of the battery pack from the second voltage signal in response to the slope being less than or equal to a defined threshold.

[0019] Among other features, determining the ratio of the first voltage value to the second voltage value involves dividing the negative center voltage by the sum of the negative center voltage and the positive center voltage.

[0020] Among other features, determining the location of the battery cell where the detected fault occurred involves multiplying a defined ratio by the total number of battery cells in the battery pack.

[0021] Among other features, the battery pack includes cell groups, each of which comprises a different set of battery cells.

[0022] Among other features, determining the ratio of the first voltage value to the second voltage value involves summing the cell group voltages of the selected quantity and dividing the total cell group voltage by the sum of the negative and positive center voltages.

[0023] Among other features, determining the location of the battery cell where the detected fault occurred involves multiplying a defined ratio by the total number of battery cells in the battery pack.

[0024] Among other features, the battery cell location is a first battery cell location, and the method further includes determining a second battery cell location of the detected fault in the battery pack, and identifying the type of fault associated with the battery pack based on the first battery cell location and the second battery cell location.

[0025] Among other features, generating alarms includes generating alarms that indicate the type of fault associated with the battery pack.

[0026] Among other features, the first battery cell location and the second battery cell location are determined at different times, and the method further includes determining whether the first battery cell location and the second battery cell location are the same.

[0027] Among other features, identifying the type of fault associated with the battery pack includes a first type of fault identified in response to the first battery cell location and the second battery cell location being the same, or a second type of fault identified in response to the first battery cell location and the second battery cell location being different.

[0028] One method includes detecting a fault associated with a battery pack comprising multiple battery cells; determining, over time, N battery cell locations in the battery pack where the detected fault is an integer greater than 2; identifying the type of fault associated with the battery pack based on the N battery cell locations; and generating an alarm indicating the type of fault associated with the battery pack.

[0029] Among other features, the N battery cell locations include at least a first battery cell location and a second battery cell location, and the method further includes determining whether the first battery cell location and the second battery cell location are the same.

[0030] Among other features, identifying the type of fault associated with the battery pack includes a first type of fault identified in response to the first battery cell location and the second battery cell location being the same, or a second type of fault identified in response to the first battery cell location and the second battery cell location being different.

[0031] This invention may also include the following technical solutions:

[0032] 1. A vehicle system for detecting faults in a battery pack, the vehicle system comprising:

[0033] A battery pack, comprising multiple battery cells;

[0034] A voltage sensor is configured to sense the output voltage of the plurality of battery cells; and

[0035] The control module communicates with the voltage sensor and is configured to:

[0036] Detect faults associated with the battery pack;

[0037] Receive a first voltage signal representing a first voltage value and a second voltage signal representing a second voltage value from a voltage sensor;

[0038] Determine the defined ratio between the first voltage value and the second voltage value;

[0039] The location of the detected fault within the battery cell in the battery pack is determined based on a defined ratio and the total number of battery cells in the battery pack; and

[0040] Generate an alarm indicating the location of the battery cell where the fault was detected.

[0041] 2. The vehicle system according to technical solution 1, wherein the first voltage value is the negative center voltage of the battery pack, and the second voltage value is the positive center voltage of the battery pack.

[0042] 3. The vehicle system according to technical solution 2, wherein the control module is configured as follows:

[0043] Determine the slopes of the first and second voltage signals; and

[0044] In response to a slope less than or equal to a defined threshold, the negative middle pack voltage of the battery pack is measured from the first voltage signal and the positive middle pack voltage of the battery pack is measured from the second voltage signal.

[0045] 4. The vehicle system according to technical solution 3, wherein the control module is configured to determine the defined ratio of the first voltage value and the second voltage value by dividing the negative center voltage by the sum of the negative center voltage and the positive center voltage.

[0046] 5. The vehicle system according to technical solution 4, wherein the control module is configured to determine the battery cell location by multiplying a defined ratio by the total number of the plurality of battery cells in the battery pack.

[0047] 6. The vehicle system according to technical solution 3, wherein:

[0048] The battery pack includes unit groups, each unit group comprising a different set of battery cells; and

[0049] The control module is configured to determine the defined ratio of the first voltage value and the second voltage value by summing the unit group voltages of the selected unit group and dividing the total unit group voltage by the sum of the negative and positive center voltages.

[0050] 7. The vehicle system according to technical solution 6, wherein the selection of unit groups is determined based on the negative intermediate voltage.

[0051] 8. The vehicle system according to technical solution 6, wherein the control module is configured to determine the battery cell location by multiplying a defined ratio by the total number of the plurality of battery cells in the battery pack.

[0052] 9. The vehicle system according to technical solution 3, wherein:

[0053] The voltage sensor includes a voltage divider with multiple resistors;

[0054] The vehicle system further includes switching devices coupled to a voltage divider; and

[0055] The control module is configured to control switching devices to connect the different sets of resistors in the voltage divider.

[0056] 10. The vehicle system according to technical solution 1, wherein:

[0057] The battery cell location is the first battery cell location; and

[0058] The control module is configured as follows:

[0059] After determining the location of the first battery cell, the location of the second battery cell in the battery pack where the fault was detected is determined; and

[0060] The type of fault associated with the battery pack is identified based on the location of the first and second battery cells.

[0061] 11. The vehicle system according to technical solution 10, wherein the control module is configured as follows:

[0062] Determine whether the positions of the first battery cell and the second battery cell are the same;

[0063] In response to the first battery cell location and the second battery cell location being identical, the type of fault associated with the battery pack is identified as the first type of fault; and

[0064] In response to the fact that the first battery cell location and the second battery cell location are different, the type of fault associated with the battery pack is identified as the second type of fault.

[0065] 12. A method for detecting a fault in a battery pack comprising multiple battery cells, the method comprising:

[0066] Detect faults associated with the battery pack;

[0067] Receive a first voltage signal representing a first voltage value of the battery pack and a second voltage signal representing a second voltage value of the battery pack from the voltage sensor;

[0068] Determine the defined ratio between the first voltage value and the second voltage value;

[0069] The location of the detected faulty battery cell is determined based on a defined ratio and the total number of battery cells in the battery pack; and

[0070] Generate an alarm indicating the location of the battery cell where the fault was detected.

[0071] 13. The method according to technical solution 12, wherein:

[0072] The first voltage value is the negative center voltage of the battery pack, and the second voltage value is the positive center voltage of the battery pack; and

[0073] The method further includes determining the slopes of a first voltage signal and a second voltage signal, and in response to the slope being less than or equal to a defined threshold, measuring the negative center voltage of the battery pack from the first voltage signal and measuring the positive center voltage of the battery pack from the second voltage signal.

[0074] 14. The method according to technical solution 13, wherein:

[0075] Determining the ratio between the first and second voltage values ​​involves dividing the negative center voltage by the sum of the negative and positive center voltages; and

[0076] Determining the location of the detected faulty battery cell involves multiplying a defined ratio by the total number of the plurality of battery cells in the battery pack.

[0077] 15. The method according to technical solution 13, wherein:

[0078] The battery pack includes unit groups, and each unit group includes a different set of battery cells;

[0079] Determining the ratio of the first voltage value to the second voltage value involves summing the cell group voltages of the selected quantity and dividing the total cell group voltage by the sum of the negative and positive center voltages; and

[0080] Determining the location of the detected faulty battery cell involves multiplying a defined ratio by the total number of the plurality of battery cells in the battery pack.

[0081] 16. The method according to technical solution 13, wherein:

[0082] The battery cell location is the first battery cell location; and

[0083] The method further includes determining the location of a second battery cell in the battery pack where a fault was detected, and identifying the type of fault associated with the battery pack based on the location of the first and second battery cells.

[0084] 17. The method according to claim 16, wherein generating an alarm includes generating an alarm indicating the type of fault associated with the battery pack.

[0085] 18. The method according to technical solution 16, wherein:

[0086] The positions of the first battery cell and the second battery cell were determined at different times;

[0087] The method further includes determining whether the positions of the first battery cell and the second battery cell are the same; and

[0088] The types of faults associated with the battery pack can be identified as follows: a first type of fault is identified in response to the first battery cell location and the second battery cell location being the same, or a second type of fault is identified in response to the first battery cell location and the second battery cell location being different.

[0089] 19. A method comprising:

[0090] Detecting faults associated with battery packs that include multiple battery cells;

[0091] Determine the locations of N battery cells in the battery pack where the detected faults occur over time, where N is an integer greater than 2;

[0092] The type of fault associated with the battery pack is identified based on the locations of the N battery cells; and

[0093] Generate alarms indicating the type of fault associated with the battery pack.

[0094] 20. The method according to technical solution 19, wherein:

[0095] The N battery cell locations include at least the first battery cell location and the second battery cell location;

[0096] The method further includes determining whether the positions of the first battery cell and the second battery cell are the same; and

[0097] The types of faults associated with the battery pack can be identified as follows: a first type of fault is identified in response to the first battery cell location and the second battery cell location being the same, or a second type of fault is identified in response to the first battery cell location and the second battery cell location being different.

[0098] Further applicability of this disclosure will become apparent from the detailed description, claims, and drawings. The detailed description and specific examples are intended for illustrative purposes only and are not intended to limit the scope of this disclosure. Attached Figure Description

[0099] This disclosure will be more fully understood from the detailed description and accompanying drawings, in which:

[0100] Figure 1 This is a block diagram of an example system for detecting location faults and identifying fault modes in a battery pack, according to the present disclosure.

[0101] Figure 2 It is based on the provisions of this disclosure, including Figure 1 The system is part of the vehicles;

[0102] Figure 3 Based on this disclosure Figure 1 A block diagram of an example battery pack for the system;

[0103] Figure 4 Based on this disclosure Figure 3 A block diagram of an example battery pack in the image;

[0104] Figure 5 This is a block diagram of another example system for detecting location faults and identifying fault modes in a battery pack, according to this disclosure;

[0105] Figures 6-7 It is based on the illustrations in this disclosure. Figure 5 A graph showing the positive and negative center pack voltages of the battery pack in the system;

[0106] Figure 8 It is based on the illustrations in this disclosure. Figure 5 A diagram showing the determined locations of battery cells in the battery pack of the system;

[0107] Figures 9-10 This is a flowchart of an example control process for detecting battery cell position faults according to this disclosure; and

[0108] Figure 11 This is a flowchart of an example control process for identifying fault modes in a battery pack, according to the present disclosure.

[0109] In the accompanying drawings, reference numerals may be reused to identify similar and / or identical elements. Detailed Implementation

[0110] Vehicles, such as electric vehicles (EVs), typically rely on rechargeable energy storage systems (RESS) to store and supply electricity to propel the vehicle. In such examples, an RSS comprises one or more high-voltage battery packs, each containing an assembly of battery cells. In some examples, the battery cells may reside within modules within each battery pack. Within the RSS, one or more battery packs are electrically isolated from components outside the battery packs, such as the vehicle's chassis. Using this configuration, the RSS or its components are coupled to high-voltage components without being grounded to, for example, the vehicle's chassis. In other words, the RSS or its components are electrically isolated from the vehicle's chassis. In such examples, the vehicle relies on a floating ground relative to the RSS. Sometimes, conditions arise in the RSS and / or other high-voltage components that cause isolation losses. However, due to isolation losses and / or the location of cells that can identify such faults, distinguishing different faults within the RSS is difficult and often requires deconstructing the RSS for analysis.

[0111] The systems and methods disclosed herein provide a solution for identifying the location of a faulty cell in a battery pack, such as a high-voltage battery pack in a vehicle. For example, if an isolation loss is detected in a vehicle and a fault associated with the battery pack in the vehicle occurs, the systems and methods herein determine the location of the voltage loss in the vehicle chassis. For example, and as further explained below, the systems and methods herein enable the determination of the location of the faulty battery cell in the battery pack based on a sensed voltage value associated with the battery pack. Once the battery cell location is determined, an alert can then be generated, providing details of the battery cell location (e.g., cell number, cell group, etc.). A user (such as a technician) can then rely on this alert to take remedial action. For example, considering the location of the faulty battery cell in the battery pack, a technician can quickly identify and locate the problem within the battery pack by narrowing down the isolation loss to a specific battery cell or a battery module with multiple cells, rather than generally narrowing it down to the entire battery pack. This, in turn, enables the rapid replacement of individual battery cells or battery modules with problems (such as battery corrosion, foreign object contamination, etc.) caused and / or resulting from the isolation loss.

[0112] Additionally, in some embodiments, the systems and methods described herein provide solutions for identifying different types of faults within a battery pack due to isolation loss. For example, and as further explained below, different types of fault modes can be identified by monitoring the location of the fault over multiple cycles. For instance, if the fault location is dynamic, moving over a large area within the battery pack, the systems and methods described herein can identify the fault as a specific fault mode, such as coolant leakage, water intrusion, etc. However, if the fault location is relatively stationary, remaining substantially in the same area within the battery pack (e.g., the same cell location), the systems and methods described herein can identify the fault as another fault mode, such as corrosion, electrolyte leakage, etc. Once identified, an alarm can then provide details belonging to the fault type. Subsequently, the severity of the isolation loss can be determined with high confidence based on the identified fault type. As a result, the user obtains valuable information and increases confidence in whether to set a Diagnostic Trouble Code (DTC) associated with the isolation loss and determine appropriate remedies.

[0113] Now refer to Figure 1 A block diagram of an example system 100 is presented, used to detect location faults and identify fault modes in a battery pack. For example... Figure 1 As shown, system 100 generally includes a battery pack 102, a voltage sensor 104 for sensing the output voltage of the battery pack 102, a control module 106, and an alarm module 108. As shown, the control module 106 communicates with the voltage sensor 104 and the alarm module 108.

[0114] although Figure 1 System 100 is illustrated as including specific dedicated modules; however, it should be understood that one or more other modules may be employed if desired. For example, modules (e.g., control module 106, alarm module 108, etc.) and / or any combination of their functions may be integrated into a single module or multiple different modules. Additionally, although system 100 is shown as including a battery pack 102, it should be understood that system 100 may include multiple battery packs. Regardless of the number of battery packs in system 100, a single battery pack or multiple battery packs may be part of the RESS.

[0115] In various embodiments, the modules and sensors of system 100 can communicate with each other and share parameters via a network such as a controller area network (CAN). In such an example, parameters can be shared via one or more data buses of the network. Accordingly, various parameters can be made available via the network to other modules and / or sensors by a given module and / or sensor.

[0116] Figure 1 System 100 can be used in any suitable implementation in which one or more high-voltage battery packs are employed. For example, system 100 can be used in a vehicle implementation or a non-vehicle implementation. Further, if system 100 is used in a vehicle implementation, system 100 can be located in a vehicle or in another suitable location, such as at a testing facility (e.g., a service location, a manufacturing location, etc.). If system 100 is located in a vehicle and implemented within the vehicle, functions for detecting location faults and fault modes in battery pack 102 (as further explained herein) are performed when the vehicle is not moving, in order to minimize noise. Regarding the vehicle implementation, system 100 can be part of any suitable vehicle having a RESS that includes one or more high-voltage battery packs for storing and supplying power to propel the vehicle. In such an example, the vehicle can be an electric vehicle, such as a pure electric vehicle, a hybrid electric vehicle, etc. Additionally, system 100 can be adapted to autonomous vehicles, semi-autonomous vehicles, etc. As an example, Figure 2 Depicting including Figure 1 The vehicle 200 includes a battery pack 102, a voltage sensor 104, and a control module 106.

[0117] Continue to refer to Figure 1 Battery pack 102 typically includes multiple battery cells. In such an example, each battery cell may be capable of storing and supplying electrical energy. In various embodiments, the defined set of battery cells may form a battery pack or battery module, wherein each battery cell can be selectively removed or replaced by another battery pack. For example, Figure 3 Depicting Figure 1 An example of battery pack 102. Figure 3 As shown, the battery pack 102 includes a battery housing 340, cell groups (generally indicated by 350) positioned within the battery housing 340, and battery leads 352, 354 coupled to the cell groups. In such an example, the cell groups include any suitable number of cell groups. For example, in Figure 3 In this embodiment, battery pack 102 includes four cell groups 350-1, 350-2, 350-3, and 350-4. In other examples, battery pack 102 may include one cell group, two cell groups, five cell groups, ten cell groups, sixteen cell groups, twenty-four cell groups, etc. Regardless of the number of cell groups, battery leads 352 and 354 electrically connect battery pack 102 (e.g., cell groups 350-1, 350-2, 350-3, and 350-4) to outputs (e.g., loads), inputs (e.g., power sources), etc.

[0118] In various embodiments, Figure 1 The battery pack 102 may include battery cells or battery packs coupled in series and / or parallel configurations to obtain different high voltages. For example, the battery cells and / or battery packs may be coupled in a manner that provides high voltages (such as suitable voltages exceeding 50V, e.g., 100V, 400V, etc.). For example, and as... Figure 2 As shown, unit groups 350-1, 350-2, 350-3, and 350-4 are coupled in series.

[0119] Additionally, in some examples, the battery cells in any of the battery packs can have a series and / or parallel configuration. For example, Figure 4 Depicting Figure 3 An example of a 350-1 battery pack. For example... Figure 4 As shown, battery pack 350-1 includes a housing 440, battery cells (generally indicated by 460) positioned within the housing 440, and leads 462, 464 coupled to the battery cells. In this example, battery pack 350-1 includes three battery cells 460-1, 460-2, and 460-3 coupled in parallel. In other examples, battery pack 350-1 may include more or fewer battery cells coupled in series, in a series / parallel configuration, etc. (e.g., two battery cells, eight battery cells, twelve battery cells, thirty-six battery cells, forty-eight battery cells, ninety-six battery cells, etc.). Figure 4 In the example, lead 462 can be equivalent to Figure 3 Battery lead 352, and lead 464 can be coupled to Figure 3 Unit group 350-2.

[0120] exist Figure 1In the example, voltage sensor 104 can be any suitable type of sensor for detecting the voltage associated with battery pack 102. For example, voltage sensor 104 can sense the output voltage of the battery cells in battery pack 102. In such an example, voltage sensor 104 can provide one or more signals (e.g., voltage signals) to control module 106 representing the voltage value of battery pack 102. In various embodiments, voltage sensor 104 can be a voltage divider comprising multiple resistors and / or another suitable type of sensor.

[0121] Continue to refer to Figure 1 The control module 106 can generally detect faults associated with the battery pack 102. For example, the control module 106 can passively or statistically detect isolation losses associated with the battery pack 102. For example, the control module 106 can receive a signal indicating that isolation losses have been detected from another module or system.

[0122] In other examples, control module 106 may detect isolation loss based on one or more sensed voltages from voltage sensor 104. In such examples, voltage sensor 104 can be used both to detect isolation loss and to determine the location of a faulty cell, as further explained herein. Accordingly, existing hardware (e.g., voltage sensor 104, etc.) can be used to perform both functions. For example, control module 106 may determine isolation resistance based on sensed voltages from voltage sensor 104 (such as the negative center voltage and positive center voltage of battery pack 102). In some examples, control module 106 may cycle a bias switch to measure the isolation resistance when the switch is open. Generally, control module 106 can detect isolation loss if the isolation resistance drops below a threshold, which is conventional.

[0123] In other examples, control module 106 may detect isolation loss or otherwise determine its presence using one or more prediction-based algorithms. For instance, in some examples, isolation resistance data from multiple operating battery packs (or multiple RESS) may be obtained. Control module 106 or another suitable module may then predict the presence of isolation loss associated with battery pack 102 by relying on parameters learned from the isolation resistance data from the other battery packs. In such examples, suitable machine learning techniques, statistical modeling, etc., may be used to learn parameters (e.g., one or more thresholds) for detecting isolation loss associated with battery pack 102.

[0124] Once a fault associated with battery pack 102 is detected, control module 106 receives a voltage signal from voltage sensor 104 representing the voltage value of battery pack 102. In various embodiments, the received voltage signal may represent the negative and positive center voltages of battery pack 102, which may be measured in any suitable manner.

[0125] For example, Figure 5 An example system 500, similar to system 100, is depicted. Figure 5 In the middle, system 500 includes having Figure 3 Unit groups 350-1, 350-2, 350-3, and 350-4 Figure 1 Battery pack 102 Figure 1 The control module 106, voltage sensor 506, and switching device 508 coupled to voltage sensor 506 and control module 106. Figure 5 In the example, voltage sensor 506 includes resistors 510, 512, 514, 516, 518, and 520 forming a switchable voltage divider configuration, and switching device 508 acts as a bias switch for determining isolation resistance, as explained above. In various embodiments, voltage sensor 506 may be located external to battery pack 102 if desired (e.g., Figure 5 (as shown in the image) or inside the battery pack.

[0126] exist Figure 5 In this example, different resistor sets 514, 516, 518, and 520 can be connected together to generate the voltage value of the battery pack 102. In such an example, the control module 106 can control the switching device 508 to connect the different resistor sets 514, 516, 518, and 520 in the voltage divider. For example, in Figure 5 In this configuration, control module 106 generates control signal 522 to control switching device 508 via a voltage divider to generate different neutral voltage values. For example, when the switching device is open (e.g., not conducting), control module 106 generates and measures a negative neutral voltage between contacts 524 and 526 based on resistors 512, 518, and 520. However, when the switching device is closed (e.g., conducting), control module 106 generates and measures a positive neutral voltage between contacts 524 and 526 based on resistors 510, 514, and 516.

[0127] Figures 6-7 Example graphs 600 and 700 illustrate the states of the positive and negative neutral voltages along with the switching device 508 over time. Specifically, in Figure 6In Figure 600, the center voltage 602 and the switching state 604 are depicted. As shown, when the switching device 508 is turned on, the center voltage 602 initially increases to nearly 400V, and then decreases and stabilizes at approximately 100V. Figure 7 In the diagram, Figure 700 depicts the negative neutral voltage 702 and the switching state 604. As shown, when the switching device 508 is turned on, the negative neutral voltage 702 initially drops to 0V, and then increases and stabilizes at approximately 285V.

[0128] Continue to refer to Figure 1 and Figure 5 Control module 106 can only use the positive and negative center pack voltages to determine the location of a faulty cell when certain parameters are met. For example, in some examples, control module 106 can only use the center pack voltage when the slope of the voltage signals representing the positive and negative center pack voltages is below a defined threshold (e.g., close to 0). In some examples, the defined threshold may be a calibration value suitable for ensuring that the positive and negative center pack voltages have stabilized (e.g., transient conditions are minimized). In such examples, control module 106 can determine the slope of the voltage signals representing the positive and negative center pack voltages (such as center pack voltages 602, 702) by monitoring the signals over time. Then, in response to a slope less than or equal to the defined threshold, control module 106 can measure (or otherwise employ) the positive center pack voltage of battery pack 102 (e.g., ...). Figure 6 The voltage of 602) and the negative middle pack voltage (e.g., Figure 7 (Voltage 702).

[0129] For example, control module 106 can determine the slope of the intermediate pack voltages 602 and 702 via one or more calculations. As an example, control module 106 can determine the slope based on the following equation (1). In equation (1), NMPV represents the negative intermediate pack voltage, PMPV represents the positive intermediate pack voltage, Cell_N represents the total number of battery cells in battery pack 102, and deltaCal represents the defined slope threshold. As shown, the ratios based on NMPV, PMPV, and Cell_N are determined at different discrete times, and the slope is determined based on the difference between the ratios. This slope is then compared with the defined slope threshold.

[0130] Equation (1)

[0131] Then, the control module 106 can determine a defined ratio of the voltage value sensed by the voltage sensor 104. In various embodiments, this determination can be made after the determined slope of the voltage value has stabilized below a defined threshold, as explained above.

[0132] exist Figure 1 and Figure 5 In the example, control module 106 can determine this defined ratio in different ways based on whether the battery cells are balanced. For example, if the battery cells are balanced so that all cells in battery pack 102 have the same voltage, the defined ratio can be determined according to equation (2) below. In such an example, control module 106 can divide the negative center pack voltage NMPV by the sum of the negative center pack voltage NMPV and the positive center pack voltage PMPV.

[0133] Equation (2)

[0134] In other examples, the battery cells can be unbalanced, such that some cells in the battery pack 102 have different voltages (e.g., different from the average cell voltage). For example, the battery pack 102 may include cell groups having a set of battery cells that output different voltages. In such an example, the defined ratio can be determined according to the following equation (3). In this example, the control module 106 selects the voltage (CGV) of each cell group (n) of the cell group (n). i The total cell group voltage is summed and then divided by the sum of the negative mid-pack voltage NMPV and the positive mid-pack voltage PMPV. In this example, the selection of cell group (n) is determined based on the negative mid-pack voltage NMPV. For example, the selection of cell group (n) could be the total number of battery cells required to satisfy the negative mid-pack voltage NMPV without exceeding this value.

[0135] Equation (3)

[0136] Next, the control module 106 can determine the location of the faulty battery cell detected in the battery pack 102. For example, the control module 106 can determine this cell location based on the defined ratio obtained according to equation (1) or equation (2) above and the total number of battery cells in the battery pack 102. As an example, equation (4) below describes the determination of the location of the faulty battery cell when the battery cells are balanced. In this example, the control module 106 determines the battery cell location (fail_loc) by multiplying the defined ratio (from equation (2)) by the total number of battery cells (Cell_N) in the battery pack 102. cell In other examples, when the battery cells are balanced, the control module 106 can determine the battery cell location (fail_loc) by multiplying a defined ratio (from equation (3)) by the total number of battery cells (Cell_N) in the battery pack 102. cell As shown in equation (5) below.

[0137] Equation (4)

[0138] Equation (5)

[0139] For example, Figure 8 Example diagram 800 depicts the determined battery cell location 802 representing a fault in battery pack 102 over time. In this example, battery pack 102 comprises a total of ninety-six battery cells (Cell_N = 96), with a negative center cell voltage NMPV of approximately 285.7 volts and a positive center cell voltage PMPV of approximately 100.3 volts. If control module 106 applies equation (4) above, the battery cell location is determined to be 71. Accordingly, in this example, control module 106 determines that the 71st cell from one end of battery pack 102 is the location of the fault.

[0140] In various embodiments, control module 106 generates an alarm indicating the location of a detected faulty battery cell. In such an example, control module 106 may transmit an alarm (e.g., a signal) to alarm module 108. In response, alarm module 108 provides a notification (e.g., a message) indicating the location of the detected faulty battery cell to, for example, a user (e.g., a technician, etc.). For example, alarm module 108 may include a display for providing visual and / or audible notifications. In other examples, alarm module 108 may include a speaker for providing audible notifications. Regardless of the type of notification used, the user may be notified that a specific battery cell (e.g., battery cell 71) is faulty, needs to be replaced, needs to be inspected, etc. In response, the user may replace only the specific battery cell with the detected fault or an entire battery pack with the specific battery cell with the detected fault.

[0141] Additionally, in some examples, the control module 106 can generally distinguish different types of fault modes within the battery pack 102 due to isolation losses. Accordingly, the control module 106 can identify the type of fault associated with the battery pack 102. For this purpose, the control module 106 can monitor one or more isolation characteristics of the entire battery pack 102 and the location of detected faults (e.g., isolation losses) in two or more cycles.

[0142] For example, control module 106 may monitor the location of a detected fault in two or more cycles only when certain conditions apply. As an example, control module 106 receives one or more thresholds (e.g., control limits) generated through machine learning techniques, statistical modeling, etc. For instance, control module 106 may receive one or more thresholds related to isolation resistance derived from analysis associated with isolation resistance data obtained from other operating battery packs. In such an example, control module 106 may begin monitoring the location of a detected fault when the isolation resistance of battery pack 102 drops below a threshold or drops below and remains below a threshold for a period of time.

[0143] The control module 106 then observes the location where the isolation loss (or more generally, the detected fault) occurs within multiple cycles. For example, after determining the initial battery cell location of the isolation loss in the battery pack 102, the control module 106 can determine at a later time at least one subsequent battery cell location of the isolation loss in the battery pack 102. In such an example, the control module 106 can determine the initial battery cell location and the subsequent battery cell location, as explained above.

[0144] Then, control module 106 identifies the type of fault associated with the battery pack based on the initial and subsequent battery cell locations. For example, control module 106 can generally predict the type of fault (e.g., cause of isolation loss) based on whether the determined battery cell locations are static or dynamic. In such an example, the initial and subsequent battery cell locations can be compared by control module 106. For example, if the initial and subsequent battery cell locations are determined to be in the same or close locations (e.g., static), control module 106 can identify the type of fault associated with battery pack 102 as a first type of fault indicating a non-moving problem (such as corrosion, electrolyte leakage, etc.). However, if the initial and subsequent battery cell locations are determined to be in different locations (e.g., dynamic), control module 106 can identify the type of fault associated with battery pack 102 as a second type of fault indicating a moving problem (such as coolant leakage, water intrusion, etc.).

[0145] Then, in various embodiments, control module 106 can generate an alarm indicating the type of fault associated with battery pack 102. For example, control module 106 can transmit the alarm to alarm module 108. In such an example, the generated alarm may include the location of one or more battery cell(s) of the detected fault and / or the type of fault associated with battery pack 102. In response, alarm module 108 may provide a notification indicating the type of fault to, for example, a user (e.g., a technician, etc.), as explained above. Using this information, the severity of the isolation loss can be determined with high confidence, and appropriate DTCs and / or predictions can be set accordingly.

[0146] Figures 9-11 The diagram illustrates what can be obtained from Figure 1 The system 100 is used for example control processes 900, 1000, and 1100 for detecting location faults and / or identifying fault modes in a battery pack. Although example control processes 900, 1000, and 1100 pertain to the inclusion of control module 106... Figure 1 System 100 is described, but any of control processes 900, 1000, and 1100 may be adopted by another suitable system.

[0147] like Figure 9 As shown, the control process 900 receives data from the battery pack (such as...) Figure 1 The control module 106 begins with data related to isolation loss in the battery pack 102. For example, and as explained above, the control module 106 may receive signals indicating isolation loss from another module or system, one or more sensed parameters associated with the battery pack (e.g., negative center pack voltage, positive center pack voltage, etc.), one or more thresholds learned from isolation resistance data, and analyses associated with other operating battery packs, etc. The control process 900 then continues to 904.

[0148] At 904, control module 106 determines whether the isolation loss was detected based on the received data. For example, and as explained herein, control module 106 can detect the isolation loss based on the received signal, sensed parameters, thresholds, etc. For example, to determine whether the isolation loss exists, control module 106 can determine the isolation resistance based on the sensed parameters and then compare the isolation resistance with a threshold (e.g., a user-defined threshold, a learned threshold, etc.). If no isolation loss is detected at 904, control returns to 902. Otherwise, if isolation loss is detected, control continues to 906.

[0149] At 906, control module 106 receives a signal from voltage sensor 104 representing the voltage value of battery pack 102. For example, and as explained above, when voltage sensor 104 is controlled with different switchable voltage divider configurations (via bias switching devices), control module 106 can receive the negative and positive center voltages of battery pack 102. Control process 900 then continues to 908 and 910.

[0150] At 908, control module 106 determines a ratio associated with the received voltage value. For example, and as explained above, control module 106 may implement equation (2) or equation (3) above to obtain this ratio. At 910, control module 106 determines the location of the battery cell with detected isolation loss in battery pack 102 based on the determined ratio and the total number of battery cells in battery pack 102. In various embodiments, control module 106 may implement equation (4) or equation (5) above to obtain this battery cell location. Then, control process 900 continues to 912.

[0151] At 912, control module 106 generates and transmits an alarm indicating the location of a battery cell with detected isolation loss in battery pack 102. For example, and as explained above, control module 106 can generate an alarm signal and transmit it to alarm module 108, which can then provide the user with a notification (e.g., a message) indicating the location of the battery cell with detected isolation loss. In such an example, the user can be notified that a specific battery cell is faulty, needs to be replaced, needs to be inspected, etc. In response, the user can replace only the specific battery cell causing the isolation loss or the entire battery pack containing the specific battery cell causing the isolation loss. Then, control process 900 can proceed as follows: Figure 9 The process can end or return to another appropriate step to continue monitoring and determining the cell location.

[0152] exist Figure 10 In the middle, control process 1000 and Figure 9 The control process is similar to 900, but includes additional steps. For example, and as... Figure 10 As shown, control process 1000 begins at 902 and then continues to the position above relative to... Figure 9 The explanations for 904 and 906. Then, control process 1000 continues to 1008.

[0153] At 1008, control module 106 determines the slope of a signal representing voltage values ​​(such as the positive and negative center voltages of battery pack 102). For example, and as explained above, control module 106 can determine the slope based on equation (1) above. Control process 1000 then proceeds to 1010, where control module 106 determines whether the determined slope is less than a defined (e.g., calibration) threshold. In various embodiments, control module 106 can make this determination based on a comparison between the determined slope (e.g., delta) and the threshold. If not at 1010, control can return to 1008, as... Figure 10 As shown in the diagram. If it is yes at 1010, then control process 1000 continues as shown above relative to... Figure 9 The explanation of 908, 910, and 912. Then, process 1000 as follows. Figure 10 The process can end or return to another appropriate step to continue monitoring and determining the cell location.

[0154] exist Figure 11 In this process, control procedure 1100 is implemented to identify fault modes in battery pack 102. For example, such as... Figure 11 As shown, control process 1100 begins at 902 and then continues to the position above relative to... Figure 9 The explanation is 904. Then, control process 1100 continues to 1106, where control module 106 determines the cell location of the detected isolation loss multiple times. For example, and as explained above, control module 106 can determine the initial battery cell location of the isolation loss in battery pack 102, and then, at a later time, determine at least one subsequent battery cell location of the isolation loss in battery pack 102. In such an example, control module 106 can, according to the explanation above... Figure 9 Steps 906, 908, and 910 determine the initial battery cell position and the subsequent battery cell position. Then, the control process 1100 continues to 1108.

[0155] At 1108, control module 106 determines whether the cell locations are different. For example, one cell location associated with the detected isolation loss may be at cell number 71 of the battery pack 102 (out of a total of 96 cells), while a subsequent cell location associated with the detected isolation loss may be at cell number 34 of the same battery pack 102. Alternatively, one cell location associated with the detected isolation loss may be at cell number 71 of the battery pack 102, and a subsequent cell location associated with the detected isolation loss may be at cell number 71 of the same battery pack 102. Based on the cell location, control module 106 can identify the type of fault (e.g., the cause of the fault) associated with battery pack 102. For example, if the initial battery cell location and the subsequent battery cell location are different, control process 1100 continues to 1110, where control module 106 identifies the type of fault associated with battery pack 102 as a first type of fault indicating a mobility problem (such as coolant leakage, water intrusion, etc.). However, if the initial battery cell location and the subsequent battery cell location are the same or substantially the same (i.e., no different), the control process 1100 continues to 1112, where the control module 106 identifies the type of fault associated with the battery pack 102 as a second type of fault indicating a non-movement problem (such as corrosion, electrolyte leakage, etc.). Then, regardless of the type of fault identified, the control process 1100 continues to 1114.

[0156] At 1114, control module 106 generates and transmits an alarm indicating the type of fault identified in battery pack 102. For example, and as explained above, control module 106 may generate an alarm signal and transmit it to alarm module 108, which in turn can provide the user with notification (e.g., a message) indicating the type of fault. In some examples, if desired, the alarm may indicate one or more cell locations in addition to the type of fault. In response, the user can confidently determine the severity of the isolation loss and / or set appropriate DTCs to take appropriate remedial action.

[0157] The foregoing description is merely illustrative in nature and is by no means intended to limit this disclosure, its application, or its use. The broad teachings of this disclosure can be implemented in various forms. Therefore, while this disclosure includes specific examples, its true scope should not be so limited, as other modifications will become apparent upon examination of the drawings, specification, and the following claims. It should be understood that one or more steps within the method may be performed in a different order (or simultaneously) without altering the principles of this disclosure. Furthermore, although each embodiment is described above as having certain features, any one or more of those features described with respect to any embodiment of this disclosure may be implemented in and / or combined with features of any other embodiment, even if such combination is not explicitly described. In other words, the described embodiments are not mutually exclusive, and substitutions of one or more embodiments with each other remain within the scope of this disclosure.

[0158] Spatial and functional relationships between components (e.g., between modules, circuit elements, semiconductor layers, etc.) are described using various terms including “connection,” “joint,” “coupled,” “proximity,” “closest,” “above,” “under,” and “set.” Unless explicitly described as “direct,” when describing the relationship between the first and second components in the above disclosure, the relationship can be a direct relationship in which no other intervening components exist between the first and second components, or it can be an indirect relationship in which one or more intervening components exist between the first and second components (spatially or functionally). As used herein, the phrase “at least one of A, B, and C” should be interpreted as meaning the logic of using a non-exclusive “OR” (A or B or C) and should not be interpreted as meaning “at least one of A, at least one of B, and at least one of C.”

[0159] In the diagrams, the direction of the arrows, as indicated by the arrowhead, generally indicates the flow of information (such as data or instructions) of interest for that diagram. For example, when components A and B exchange various information, but the information transmitted from component A to component B is relevant to this diagram, the arrow can point from component A to component B. This unidirectional arrow does not imply that no other information is transmitted from component B to component A. Furthermore, for information sent from component A to component B, component B can send a request for or confirmation of receipt of that information to component A.

[0160] In this application, including the following definitions, the term "module" or "controller" may be replaced by the term "circuit". The term "module" may refer to, be part of, or include the following: application-specific integrated circuit (ASIC); digital, analog, or mixed-signal analog / digital discrete circuit; digital, analog, or mixed-signal analog / digital integrated circuit; combinational logic circuit; field-programmable gate array (FPGA); processor circuitry (shared, dedicated, or grouped) that executes code; memory circuitry (shared, dedicated, or grouped) that stores code executed by the processor circuitry; other suitable hardware components that provide the described functionality; or some or all of the foregoing, such as in a system-on-a-chip.

[0161] A module may include one or more interface circuits. In some examples, the interface circuit may include a wired or wireless interface connected to a local area network (LAN), the Internet, a wide area network (WAN), or a combination thereof. The functionality of any given module of this disclosure may be distributed among multiple modules connected via the interface circuit. For example, multiple modules may allow for load balancing. In a further example, a server (also referred to as a remote or cloud) module may perform some functions on behalf of a client module.

[0162] The term "code," as used above, can include software, firmware, and / or microcode, and can refer to programs, routines, functions, classes, data structures, and / or objects. The term "shared processor circuitry" covers a single processor circuitry that executes some or all of the code from multiple modules. The term "group processor circuitry" covers processor circuitry that executes some or all of the code from one or more modules in combination with additional processor circuitry. References to multiple processor circuitry cover multiple processor circuitry on a discrete die, multiple processor circuitry on a single die, multiple cores of a single processor circuitry, multiple threads of a single processor circuitry, or a combination of the foregoing. The term "shared memory circuitry" covers a single memory circuitry that stores some or all of the code from multiple modules. The term "group memory circuitry" covers memory circuitry that stores some or all of the code from one or more modules in combination with additional memory.

[0163] The term "memory circuit" is a subset of the term "computer-readable medium." As used herein, the term "computer-readable medium" does not cover transient electrical or electromagnetic signals propagated through a medium (such as on a carrier wave); therefore, the term "computer-readable medium" can be considered tangible and non-transient. Non-limiting examples of non-transient tangible computer-readable media are non-volatile memory circuits (such as flash memory circuits, erasable programmable read-only memory circuits, or mask-mode read-only memory circuits), volatile memory circuits (such as static random access memory circuits or dynamic random access memory circuits), magnetic storage media (such as analog or digital magnetic tape or hard disk drives), and optical storage media (such as CDs, DVDs, or Blu-ray discs).

[0164] The apparatus and methods described in this application can be implemented, in part or in whole, by a special-purpose computer created by configuring a general-purpose computer to perform one or more specific functions embodied in a computer program. The function blocks, flowchart components, and other elements described above serve as software specifications that can be translated into computer programs through the routine work of a skilled technician or programmer.

[0165] A computer program includes processor-executable instructions stored on at least one non-transitory tangible computer-readable medium. A computer program may also include or depend on stored data. A computer program may encompass a basic input / output system (BIOS) that interacts with the hardware of a special-purpose computer, device drivers that interact with specific devices of the special-purpose computer, one or more operating systems, user applications, background services, background applications, etc.

[0166] Computer programs may include: (i) descriptive text to be parsed, such as HTML (Hypertext Markup Language), XML (Extensible Markup Language), or JSON (JavaScript Object Notation); (ii) assembly code; (iii) object code generated by a compiler from source code; (iv) source code for execution by an interpreter; and (v) source code for compilation and execution by a just-in-time (JIT) compiler, etc. As an example only, source code may be written using syntax from languages ​​including: C, C++, C#, Objective-C, Swift, Haskell, Go, SQL, R, Lisp, etc. Fortran, Perl, Pascal, Curl, OCaml, HTML5 (Hypertext Markup Language 5), Ada, ASP (Active Server Pages), PHP (PHP: Hypertext Preprocessor), Scala, Eiffel, Smalltalk, Erlang, Ruby, Visual Lua, MATLAB, SIMULINK and

Claims

1. A vehicle system for detecting faults in a battery pack, the vehicle system comprising: A battery pack, comprising multiple battery cells; A voltage sensor is configured to sense the output voltage of the plurality of battery cells; as well as The control module communicates with the voltage sensor and is configured to: Detect faults associated with the battery pack; Receive a first voltage signal representing a first voltage value and a second voltage signal representing a second voltage value from a voltage sensor; Determine the defined ratio between the first voltage value and the second voltage value; The location of the detected fault in the battery cell within the battery pack is determined based on the defined ratio and the total number of the multiple battery cells in the battery pack. as well as Generate an alarm indicating the location of the battery cell where the fault was detected.

2. The vehicle system according to claim 1, wherein the first voltage value is the negative center voltage of the battery pack, and the second voltage value is the positive center voltage of the battery pack.

3. The vehicle system according to claim 2, wherein the control module is configured to: Determine the slopes of the first and second voltage signals; and In response to a slope less than or equal to a defined threshold, the negative middle pack voltage of the battery pack is measured from the first voltage signal and the positive middle pack voltage of the battery pack is measured from the second voltage signal.

4. The vehicle system of claim 3, wherein the control module is configured to determine a defined ratio of the first voltage value and the second voltage value by dividing the negative center voltage by the sum of the negative center voltage and the positive center voltage.

5. The vehicle system of claim 4, wherein the control module is configured to determine the battery cell location by multiplying a defined ratio by the total number of the plurality of battery cells in the battery pack.

6. The vehicle system according to claim 3, wherein: The battery pack includes unit groups, each unit group comprising a different set of battery cells; and The control module is configured to determine the defined ratio of the first voltage value and the second voltage value by summing the unit group voltages of the selected unit group and dividing the total unit group voltage by the sum of the negative and positive center voltages.

7. The vehicle system of claim 6, wherein the control module is configured to determine the battery cell location by multiplying a defined ratio by the total number of the plurality of battery cells in the battery pack.

8. The vehicle system according to claim 1, wherein: The battery cell location is the first battery cell location; and The control module is configured as follows: After determining the location of the first battery cell, the location of the second battery cell in the battery pack where the fault was detected is determined; and The type of fault associated with the battery pack is identified based on the location of the first and second battery cells.

9. A method comprising: Detecting faults associated with battery packs that include multiple battery cells; Determine the locations of N battery cells in the battery pack where the detected faults occur over time, where N is an integer greater than 2; The type of fault associated with the battery pack is identified based on the location of the N battery cells; as well as Generate alarms indicating the type of fault associated with the battery pack.

10. The method according to claim 9, wherein: The N battery cell locations include at least the first battery cell location and the second battery cell location; The method further includes determining whether the positions of the first battery cell and the second battery cell are the same; and The types of faults associated with the battery pack can be identified as follows: a first type of fault is identified in response to the first battery cell location and the second battery cell location being the same, or a second type of fault is identified in response to the first battery cell location and the second battery cell location being different.

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