Impedance balancing of monitoring circuit for battery of vehicle

Abstract

A method of impedance balancing of a monitoring circuit for a battery of a vehicle is provided. The method includes calculating a plurality of trace resistance values for a plurality of traces of a monitoring circuit, the monitoring circuit electrically connecting a battery to a battery cell monitoring unit, the battery including a plurality of battery cells. The method further includes determining a maximum trace resistance value of the plurality of trace resistance values. The method further includes calculating a difference between the maximum trace resistance value and each trace resistance value of the plurality of trace resistance values. The method further includes identifying a subset of the plurality of traces having trace resistance values that differ by greater than a threshold resistance. The method further includes causing a resistor to be added to each trace of a subset of the plurality of traces having a trace resistance value that differs by greater than a threshold resistance.

Description

Technical Field

[0001] This disclosure relates to vehicles, and more particularly to impedance balancing of monitoring circuitry for batteries in vehicles. Background Technology

[0002] Many modern vehicles use batteries to store electrical energy and distribute it to various components within the vehicle. Some vehicles employ battery management systems (BMS), which are particularly useful for managing rechargeable batteries, such as in electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and energy storage systems. The BMS provides functions for monitoring battery status, managing charging and discharging processes, ensuring safety, and optimizing battery performance and lifespan. Impedance balancing of the monitoring circuitry used for the vehicle's batteries is desirable. Summary of the Invention

[0003] In one embodiment, a computer-implemented method for impedance balancing of a monitoring circuit for a vehicle battery is provided. The method includes calculating multiple trace resistance values ​​for multiple traces of the monitoring circuit electrically connected to a battery cell monitoring unit, the battery comprising multiple battery cells. The method further includes determining a maximum trace resistance value among the multiple trace resistance values. The method further includes calculating the difference between the maximum trace resistance value and each of the multiple trace resistance values. The method further includes identifying a subset of the multiple traces having trace resistance values ​​with a difference greater than a threshold resistance. The method further includes causing a resistor to be added to each trace in the subset of traces having trace resistance values ​​with a difference greater than the threshold resistance.

[0004] In addition to one or more features described herein, or as an alternative, further embodiments of the method may include resistors added to a subset of traces having trace resistance values ​​with a difference greater than a threshold resistance, the resistance values ​​of each trace being at least partially based on the difference greater than a threshold resistance.

[0005] In addition to one or more features described herein, or as an alternative, further embodiments of the method may include resistors selected from a set of resistors having predefined resistance values.

[0006] In addition to one or more features described herein, or as an alternative, further embodiments of the method may include the selection of resistors from a set of resistors having predefined resistance values ​​based at least in part on the difference being greater than a threshold resistance.

[0007] In addition to one or more features described herein, or as an alternative, further embodiments of the method may include a surface-mount device resistor.

[0008] In addition to one or more features described herein, or as an alternative, further embodiments of the method may include that the battery is a rechargeable battery.

[0009] In addition to one or more features described herein, or as an alternative, further embodiments of the method may include determining a minimum resistance change for each of a plurality of traces, determining a maximum resistance change for each of the plurality of traces, and for each trace in a subset of the plurality of traces having trace resistance values ​​with a difference greater than a threshold resistance, calculating updated plurality of trace resistance values ​​for the plurality of traces after adding a resistor to a monitoring circuit, and verifying that the updated plurality of trace resistance values ​​are within the range defined by the minimum resistance change and the maximum resistance change.

[0010] In addition to one or more features described herein, or as an alternative, further embodiments of the method may include traces in a plurality of traces having substantially equal widths and substantially equal thicknesses.

[0011] In addition to one or more features described herein, or as an alternative, further embodiments of the method may include traces of varying lengths among a plurality of traces.

[0012] In addition to one or more features described herein, or as an alternative, further embodiments of the method may include that the plurality of battery cells of the battery are prismatic battery cells.

[0013] In addition to one or more features described herein, or as an alternative, further embodiments of the method may include that the plurality of battery cells of the battery are cylindrical battery cells.

[0014] In another embodiment, a processing system is provided for performing impedance balancing of a monitoring circuit for a vehicle battery. The processing system includes a memory having computer-readable instructions and a processing device for executing the computer-readable instructions, which control the processing system to perform operations. The operations include calculating multiple trace resistance values ​​of multiple traces of a monitoring circuit electrically connected to a battery cell monitoring unit, the battery including multiple battery cells. These operations further include determining a maximum trace resistance value among the multiple trace resistance values. These operations further include calculating the difference between the maximum trace resistance value and each of the multiple trace resistance values. These operations further include identifying a subset of the multiple traces having trace resistance values ​​with a difference greater than a threshold resistance. These operations further include identifying a resistor to be added to each trace in the subset of multiple traces having trace resistance values ​​with a difference greater than a threshold resistance.

[0015] In addition to one or more features described herein, or as an alternative, further embodiments of the processing system may include a resistor value for each trace added to a subset of traces having trace resistance values ​​with a difference greater than a threshold resistance, at least in part based on the difference greater than the threshold resistance.

[0016] In addition to one or more features described herein, or as an alternative, further embodiments of the processing system may include resistors selected from a set of resistors having predefined resistance values, at least in part based on a difference greater than a threshold resistance.

[0017] In addition to one or more features described herein, or as an alternative, further embodiments of the processing system may include a surface-mount device resistor.

[0018] In addition to one or more features described herein, or as an alternative, further embodiments of the processing system may include a rechargeable battery.

[0019] In addition to one or more features described herein, or as an alternative, further embodiments of the processing system may include the operation further comprising determining a minimum resistance change for each of a plurality of traces, determining a maximum resistance change for each of the plurality of traces, calculating updated plurality of trace resistance values ​​for each of a subset of the plurality of traces having trace resistance values ​​with a difference greater than a threshold resistance, after adding a resistor to the monitoring circuit, and verifying that the updated plurality of trace resistance values ​​are within the range defined by the minimum resistance change and the maximum resistance change.

[0020] In addition to one or more features described herein, or as an alternative, further embodiments of the processing system may include traces among a plurality of traces having substantially equal widths and substantially equal thicknesses.

[0021] In addition to one or more features described herein, or as an alternative, further embodiments of the processing system may include traces of varying lengths among a plurality of traces.

[0022] In another embodiment, a computer program product is provided. The computer program product includes a set of one or more computer-readable storage media and program instructions, collectively stored in the set of one or more storage media, for causing a processor set to perform computer operations for impedance balancing of a monitoring circuit for a vehicle's battery. The computer operations include calculating multiple trace resistance values ​​of multiple traces of a monitoring circuit electrically connecting a battery to a battery cell monitoring unit, the battery including multiple battery cells. These operations further include determining a maximum trace resistance value among the multiple trace resistance values. These operations further include calculating the difference between the maximum trace resistance value and each of the multiple trace resistance values. These operations further include identifying a subset of the multiple traces having trace resistance values ​​with a difference greater than a threshold resistance. These operations further include identifying a resistor to be added to each trace in the subset of multiple traces having trace resistance values ​​with a difference greater than a threshold resistance. These operations further include determining a minimum resistance change for each of the multiple traces. These operations further include determining a maximum resistance change for each of the multiple traces. These operations further include, for each trace in a subset of traces having trace resistance values ​​greater than a threshold resistance, calculating updated trace resistance values ​​for the multiple traces after a resistor has been added to the monitoring circuit. These operations further include verifying that the updated trace resistance values ​​are within a range defined by the minimum and maximum resistance changes.

[0023] The above-described features and advantages, as well as other features and advantages, of this disclosure will become apparent when taken in conjunction with the accompanying drawings and the following detailed description. Attached Figure Description

[0024] Other features, advantages, and details appear only as examples in the following detailed description, which is described in detail with reference to the accompanying drawings, in which:

[0025] Figure 1 A vehicle having a circuit monitoring unit and a battery according to one or more embodiments is shown;

[0026] Figure 2 An illustration is provided according to one or more embodiments. Figure 1 Circuit monitoring unit;

[0027] Figure 3A , 3B Together with 3C, it is shown according to one or more embodiments. Figure 1 The battery;

[0028] Figure 4 An illustration is provided according to one or more embodiments. Figure 2 The battery and monitoring circuitry;

[0029] Figure 5A flowchart illustrating an impedance balancing method for a monitoring circuit of a vehicle battery according to one or more embodiments is shown; and

[0030] Figure 6 A block diagram of an impedance balancing processing system for a battery monitoring circuit for a vehicle, according to one or more embodiments, is shown. Detailed Implementation

[0031] The following description is exemplary in nature only and is not intended to limit this disclosure, its application, or use. It should be understood that throughout the drawings, corresponding reference numerals denote the same or corresponding parts and features. As used herein, the term "module" refers to processing circuitry that may include application-specific integrated circuits (ASICs), electronic circuitry, processor (shared, dedicated, or group) and memory executing one or more software or firmware programs, combinational logic circuitry, and / or other suitable components that provide the described functionality.

[0032] One or more embodiments described herein relate to impedance balancing in a monitoring circuit for a vehicle battery.

[0033] Many modern vehicles store electricity in batteries and distribute it to various components. Some vehicles use battery management systems (BMS), which are particularly useful for managing batteries, such as in electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and energy storage systems. BMS provides functions for monitoring battery status, managing charging and discharging processes, ensuring safety, and optimizing the performance and lifespan of power storage cells. BMS can utilize a battery cell monitoring unit to monitor the battery cells using monitoring circuitry. The monitoring circuitry connects the battery to the battery cell monitoring unit, which can sense battery characteristics such as voltage and current via the monitoring circuitry. In some implementations, the monitoring circuitry includes traces for each battery cell, allowing the battery cell monitoring unit to monitor the battery cells individually.

[0034] In high-voltage (e.g., essentially 400 volts to essentially 800 volts) electrical storage systems, such as in vehicles, imbalances can occur in the monitoring circuitry due to varying distances between the traces of the battery cells and the battery cell monitoring units. This imbalance can lead to inaccuracies in voltage measurements and differences in balancing current.

[0035] Existing methods attempt to address this problem by varying the trace width of the sensing circuit. For example, this approach involves adjusting the trace width to match the impedance across different circuits. However, this method is often inadequate due to physical constraints and design limitations, particularly in areas where traces converge near connector junctions. Failure to achieve impedance matching can lead to additional voltage drops and inaccuracies in cell voltage measurements, as well as imbalances in cell balancing currents. These drawbacks highlight the need for a more efficient solution to ensure accurate and reliable monitoring of cell voltages.

[0036] One or more embodiments described herein overcome these and other drawbacks by providing impedance balancing for the monitoring circuitry of a vehicle's battery. One or more embodiments address impedance imbalances in the monitoring circuitry (e.g., battery cell voltage sensing circuitry) by utilizing value-matched surface-mount device (SMD) resistors on the intermediate interconnect board (ICB) circuitry. This method involves designing traces with a fixed thickness and width, calculating the resistance value of each trace, and adding an SMD resistor to at least one of the traces to equalize the impedance between the traces. By implementing this method, impedance differences caused by varying trace lengths are mitigated, thereby improving the accuracy of battery cell voltage measurements and consistent battery cell balancing current. This solution is particularly beneficial for high-voltage battery designs with multiple stacked battery cells, ensuring reliable performance and extended battery life.

[0037] Figure 1 A vehicle 100 with a battery cell monitoring unit 102 and a battery 104 is shown according to one or more embodiments. The vehicle 100 may be a car, truck, van, bus, motorcycle, boat, or any other type of vehicle. According to one embodiment, the vehicle 100 is a hybrid electric vehicle, such as a plug-in hybrid electric vehicle (PHEV) that is partially or fully powered by electricity. According to another embodiment, the vehicle 100 is an electric vehicle powered by electricity. The battery 104 is used to provide power to components of the vehicle 100, such as an electric motor (not shown), electrical components (not shown), and / or the like, including combinations and / or multiples thereof. According to one or more embodiments, the vehicle 100 is an autonomous or semi-autonomous vehicle. An autonomous vehicle is a vehicle with autonomous driving capabilities. A semi-autonomous vehicle is a vehicle with some autonomous features (e.g., self-parking, lane keeping, etc.) but lacks fully autonomous control.

[0038] Battery cell monitoring unit 102 monitors and manages the performance of battery 104. Battery 104 stores and provides power. According to one or more embodiments, battery 104 includes multiple battery cells. Battery 104 may be a high-voltage (e.g., substantially 400 volts to substantially 800 volts) rechargeable battery.

[0039] Now for reference Figure 2-5 Further features of the battery cell monitoring unit 102 are described.

[0040] In particular, Figure 2 According to one or more embodiments Figure 1 A block diagram of a battery cell monitoring unit 102. According to one or more embodiments, the battery cell monitoring unit 102 includes a processing device 202, a memory 204, and a monitoring engine 210. It should be understood that the battery cell monitoring unit 102 can be any device suitable for monitoring and managing the battery 104. For example, the battery cell monitoring unit 102 can be a device implemented in or otherwise associated with the vehicle 100, such as an electronically controlled battery cell (also referred to as an electronic control module). As another example, the battery cell monitoring unit 102 can be a smartphone, tablet computer, laptop computer, desktop computer, wearable computing device, etc., including combinations and / or multiple thereof. As yet another example, the battery cell monitoring unit 102 can be... Figure 6 The processing system 600 and / or may include Figure 6 One or more components of the processing system 600.

[0041] Battery cell monitoring unit 102 monitors and manages the performance of battery 104 (e.g., a high-voltage rechargeable battery), including one or more battery cells of battery 104. According to one or more embodiments, battery cell monitoring unit 102 is responsible for ensuring accurate voltage sensing, effective battery cell balancing, and overall performance of battery 104. Battery cell monitoring unit 102 receives information (e.g., signals) about battery 104 from monitoring circuitry 212. According to one or more embodiments, battery cell mounting unit 102 may be integrated into battery 104. In other embodiments, battery cell monitoring unit 102 may be separate from and communicate with battery 104.

[0042] The battery monitoring unit 102 includes a processing device 202, which is any suitable processing circuitry for executing instructions and processing data. The processing device 202 can be a microcontroller, microprocessor, application-specific integrated circuit (ASIC), or any other type of processing battery cell capable of handling the computational needs of the battery monitoring unit 102. The processing device 202 is... Figure 6 Examples of one or more of the processing devices 621 are described in more detail herein.

[0043] The memory 204 within the battery cell monitoring unit 102 stores data and algorithms useful for the operation of the battery cell monitoring unit 102. This may include real-time data processing, historical data analysis, and storage of firmware or software programs. The memory 204 is any suitable device for storing data and / or instructions. For example, the memory 204 may be a combination of volatile memory (e.g., random access memory) and non-volatile memory (e.g., read-only memory, flash memory). The memory 204 is... Figure 6 Examples of one or more of system memory 622, random access memory 623, and / or read-only memory 624 are described in more detail herein.

[0044] Monitoring engine 210 is a dedicated component within battery cell monitoring unit 102 designed to monitor battery 104. Monitoring engine 210 collects and processes data from monitoring circuitry 212, including voltage, current, and / or temperature measurements. According to one or more embodiments, monitoring engine 210 ensures data accuracy and reliability, for example, by verifying the data, enabling battery cell monitoring unit 102 to make informed decisions regarding the state of charge (SOC) and state of health (SOH) of battery 104 and / or its battery cells. According to one or more embodiments, monitoring engine 210 performs impedance balancing of monitoring circuitry 212. Impedance balancing involves calculating the resistance values ​​of the traces connecting the battery cells of battery 104 to monitoring circuitry 212 of battery cell monitoring unit 102, identifying differences, and adding value-matched SMD resistors to substantially equalize the impedance. This ensures accurate voltage measurements and consistent battery cell balancing current. Although monitoring engine 210 is described as performing impedance balancing in this embodiment, it should be understood that impedance balancing can be performed by other systems or devices. According to one or more embodiments, Figure 6 The 600 processing system performs impedance balancing.

[0045] According to one or more embodiments, the battery cell monitoring unit 102 includes a communication interface (not shown) that enables the battery cell monitoring unit 102 to communicate with other systems of the vehicle 100, external devices, or remote processing systems. This interface may support various communication protocols, such as Controller Area Network (CAN) bus, Local Interconnect Network (LIN) bus, or other automotive communication standards, thereby enabling seamless integration with the electronic control unit (ECU) of the vehicle 100.

[0046] According to one or more embodiments, the battery cell monitoring unit 102 may be a component of a battery management system (BMS) (not shown), which may include battery protection features to protect the battery 104 and the vehicle 100. For example, the BMS may include overvoltage protection, undervoltage protection, overcurrent protection, and / or overtemperature protection. These safety measures help prevent damage to the battery cell and ensure the overall operational performance of the vehicle 100 and the battery 104.

[0047] According to one or more embodiments, the BMS manages the power flow to and from the battery cells of battery 104, thereby optimizing the charging and discharging process. This helps to extend the life of battery 104 and improve the overall performance of vehicle 100 and battery 104.

[0048] about Figure 2 The various components, modules, engines, etc., described herein (e.g., monitoring engine 210) can be implemented as instructions stored on a computer-readable storage medium, hardware modules, special-purpose hardware (e.g., special-purpose hardware, application-specific integrated circuits (ASICs), special-purpose processors (ASSPs), field-programmable gate arrays (FPGAs), embedded controllers, hardwired circuitry, etc.), or some combination or combination of these. According to aspects of this disclosure, the engine described herein (e.g., monitoring engine 210) can be a combination of hardware and programming. Programming can be processor-executable instructions stored on tangible memory, and the hardware can include a processing device 202 for executing those instructions. Therefore, system memory (e.g., memory 204) and / or a computer-readable storage medium can store program instructions that implement the engine described herein when executed by the processing device 202. Other engines can also be utilized to include other features and functions described in other examples herein. Reference now is made to... Figures 3A to 5 The features and functions of the monitoring engine 210 are described in more detail.

[0049] Figures 3A to 3C A battery 104 according to one or more embodiments is shown together. The battery includes battery cells 302. The number and type of battery cells 302 may vary depending on the design of the battery 104. The battery cells 302 are connected to a monitoring circuit 212 via traces 304. Figure 3A In the process, battery unit 302a is connected to trace 304a, battery unit 302b is connected to trace 304b, battery unit 302c is connected to trace 304c, and battery unit 302d is connected to trace 304d. Figure 3B and 3C Details of the battery 104, including battery cells 302a-302d, are shown.

[0050] like Figure 3AAs is evident, traces 304a to 304d vary in length, and therefore, their inherent resistance varies due to the characteristics of the traces themselves (e.g., length, width, thickness, material type and properties, including combinations and / or multiples thereof). For example, consider a battery with 56 prismatic cell units. In this example, the first group of cell units with a trace length of 28 mm has an inherent resistance of 0.03 ohms, and the last group of cell units with a trace length of 1882 mm has an inherent resistance of 1.90 ohms. In this example, the difference in inherent resistance between the last group of cell units and the first group is approximately 64 times higher.

[0051] Continue to refer to Figure 3A The table below defines the trace lengths (in mm) and associated intrinsic resistance values ​​(in ohms) for traces 304a-304d:

[0052] Trace 304a Trace 304b Trajectory 304c Trajectory 304d length 255.62 mm 192.87 mm 1233.14 mm 1266.05 mm Inherent resistance 0.26 ohms 0.20 ohms 1.25 ohms 1.28 ohms

[0053] As is evident from the table, traces with longer trace lengths tend to have higher inherent resistance values. It should be understood that the values ​​in the table are illustrative examples, not limiting ones.

[0054] To address the inherent resistance differences caused by varying trace lengths, one or more embodiments described herein implement value-matched SMD resistors on the traces (e.g., traces 304a-304d) to resolve this impedance mismatch problem.

[0055] Figure 4 Description according to one or more embodiments Figure 2 The battery 104 and monitoring circuit 212. To perform impedance matching on the monitoring circuit 212, the following process is performed according to one or more embodiments, which will refer to... Figure 5 A more detailed description follows. The trace resistance value (e.g., inherent resistance) for each trace is calculated, the maximum trace resistance value is determined, the difference between the maximum resistance value and the trace resistance value for each trace is calculated, traces with significant differences (e.g., greater than a threshold resistance) are identified, and resistors are added to the traces to balance the impedance. These steps collectively ensure that the monitoring circuit 212 operates accurately and reliably, thereby addressing the impedance imbalance problem in high-voltage rechargeable batteries.

[0056] exist Figure 4The example illustrates the inherent resistance of the traces. For instance, trace 304a has an inherent resistance of 0.26 ohms 402a, trace 304b has an inherent resistance of 0.20 ohms 402b, trace 304c has an inherent resistance of 1.25 ohms 402c, and trace 304d has an inherent resistance of 1.28 ohms 402d. The maximum trace resistance value of trace 304d is determined to be 1.28 ohms (e.g., inherent resistance 402d), and this value is used to calculate the difference between each of the other traces. For instance, the difference for trace 304a is 1.02 ohms (1.28 ohms - 0.26 ohms), the difference for trace 304b is 1.08 ohms (1.28 ohms - 0.20 ohms), and the difference for trace 304c is 0.03 ohms (1.28 ohms - 1.25 ohms). These differences are then compared to a threshold resistance, which can be a defined value or a percentage difference. For example, the threshold resistance could be 0.2 ohms (or another suitable value). In this example, the inherent resistances 402a and 402b are greater than the threshold resistance, and the inherent resistance 402c is not greater than the threshold resistance. SMD resistors with a resistance value of 1.0 ohms (e.g., resistors 404a and 404b) can be added to each of traces 304a and 304b to perform impedance matching. With the added resistors, the effective resistance value of each of traces 304a and 304b (i.e., the resistance value of the added resistor combined with the inherent resistance of the trace) is within the threshold resistance relative to the inherent resistance 402d of trace 304d.

[0057] Figure 5 A flowchart of a method 500 for monitoring multiple battery cells of a battery in a vehicle (e.g., vehicle 100) according to one or more embodiments is shown. Method 500 can be implemented using any suitable system or device. For example, method 500 and its steps can be implemented using... Figure 1 and Figure 2 The battery cell monitoring unit 102, through Figure 6 This is achieved through processing systems such as 600 (including combinations and / or multiple systems). Now refer to... Figure 1-4 Method 500 is described, but is not limited to this.

[0058] At block 502, method 500 includes calculating multiple trace resistance values ​​for multiple traces (e.g., trace 304) of monitoring circuit 212. A trace resistance value defines an amount of resistance (in ohms) inherent in the trace. That is, a trace has an inherent amount of resistance that depends on the trace's dimensions (e.g., length, width, thickness), material type and characteristics, wiring, etc. For example, a longer trace has a higher trace resistance value compared to a shorter trace, where other properties (e.g., width, thickness, material type and characteristics, etc.) are substantially the same. Monitoring circuit 212 electrically connects battery 104 to battery cell monitoring unit 102, and battery 104 includes multiple battery cells (e.g., battery cell 302). According to one or more embodiments, monitoring circuit 212 may be integrated into battery 104 such that battery 104 contains monitoring circuit 212. This step ensures that the resistance value of trace 304 is known, which is useful for subsequent impedance balancing.

[0059] At box 504, method 500 includes determining the maximum trace resistance value among the plurality of trace resistance values. The maximum trace resistance value is the largest / highest resistance value (in ohms) among the plurality of trace resistance values. Identifying the trace with the highest resistance value is useful for establishing a reference point for balancing the impedance of the other traces.

[0060] At block 506, method 500 includes calculating the difference between the maximum trace resistance value and each of the plurality of trace resistance values. That is, for each of the plurality of trace resistance values, the trace resistance value is subtracted from the maximum trace resistance value to determine the difference. This step quantifies the impedance difference between traces relative to the trace with the maximum trace resistance value, which is necessary to identify which traces require adjustment.

[0061] At block 508, method 500 includes identifying a subset of the plurality of traces having a difference in resistance value greater than a threshold resistance. For example, the threshold resistance may be set to a specific resistance value (e.g., 0.1 ohms), and any trace having a resistance value with a difference greater than 0.1 ohms is identified and included in the subset. This step filters out traces with significant impedance differences that will be processed to achieve balanced impedance while bypassing traces with a nominal (e.g., less than the threshold resistance) difference.

[0062] At block 510, method 500 includes adding a resistor (e.g., an SMD resistor) to each of a subset of traces having trace resistance values ​​with a difference greater than a threshold resistance. That is, for each trace in the subset, an SMD resistor may be added to the trace to reduce the difference between the trace's inherent resistance and the trace with the largest trace resistance value. According to one or more embodiments, the added resistors are value-matched to balance the impedance between the traces, ensuring accurate voltage measurements and consistent battery cell balancing current. That is, the added resistor is selected at least in part based on the difference. According to one or more embodiments, the added resistor is selected from a set of resistors having predefined resistance values. This is useful where a variety of standard resistors (e.g., commercially available resistors) are available, and the resistor to be added can be selected from the available standard resistors.

[0063] According to one or more embodiments, method 500 may include performing a verification process to verify that the trace resistance value is satisfactory once the added resistor is implemented. The verification process ensures that the impedance balance is effective and that the trace resistance value is within acceptable limits. The verification process will now be described in more detail.

[0064] The verification process can begin by determining the minimum resistance change for each of the multiple traces. This step involves calculating the minimum difference in resistance values ​​between the traces. The minimum resistance change provides a baseline for understanding the range of resistance values ​​present in monitoring circuitry 212.

[0065] Next, the verification process involves determining the maximum resistance change for each of the multiple traces. This step involves calculating the maximum difference in resistance values ​​between the traces. The maximum resistance change helps identify the degree of impedance imbalance in monitoring circuit 212.

[0066] Once the minimum and maximum resistance changes are determined, for each trace in a subset of traces with resistance values ​​greater than the threshold resistance, the verification process calculates updated trace resistance values ​​for the multiple traces after a resistor is added to the monitoring circuit. This step involves recalculating the trace resistance values ​​after adding a value-matched resistor to a trace with a significant impedance difference (e.g., greater than the threshold resistance). This updated calculation ensures that the added resistor has effectively balanced the impedance.

[0067] The verification process concludes by confirming that the updated trace resistance values ​​remain within the range defined by the minimum and maximum resistance changes. This step involves checking whether the recalculated resistance values ​​fall within the acceptable range defined by the minimum and maximum resistance changes. This verification step ensures that impedance balancing has been successful and that the monitoring circuit is operating within the expected parameters.

[0068] Additional processes may also be included, and it should be understood that... Figure 5 The processes described herein are illustrative, and other processes may be added, or existing processes may be removed, modified, or rearranged without departing from the scope of this disclosure. It should also be understood that... Figure 5 The process described herein can be implemented as programming instructions stored on a non-transitory computer-readable storage medium, when executed by a computing system (e.g., Figure 1 and Figure 2 Battery cell monitoring unit 102, Figure 6 Processing systems such as 600, including combinations and / or multiple processors (e.g., Figure 2 Processing equipment 202 Figure 6 When a processor 621, etc., including combinations and / or multiple thereof, is executed, the processor performs the process described herein.

[0069] The one or more embodiments described herein provide several significant benefits over existing methods of impedance matching in monitoring circuits for vehicle batteries, particularly in improving monitoring circuits for high-voltage rechargeable batteries. Such benefits may include one or more of the following:

[0070] Enhanced accuracy in voltage sensing: By calculating the resistance value of each trace and adding value-matched resistors to balance the impedance, one or more embodiments ensure that the voltage drop across each trace is consistent. This results in more accurate voltage measurements for each cell of battery 104, which is useful for monitoring the SOC and SOH of the cells in battery 104. In contrast, existing methods that vary the trace width often fail to achieve accurate impedance matching, leading to inaccurate voltage readings.

[0071] Consistent cell balancing current: Impedance balancing ensures that the balancing current is consistent across the cells of battery 104. This is useful for effective cell balancing, which equalizes the charge across the cells to prevent overcharging and / or undercharging. Existing methods that rely on varying trace widths can lead to differences in balancing current, causing some cells to degrade faster than others and reducing the overall lifespan of battery 104.

[0072] Simplified Design and Manufacturing: One or more embodiments involve designing traces with fixed thickness and width, which simplifies the design and manufacturing process. Adding SMD resistors to balance impedance is a simple and scalable solution. In contrast, existing methods of varying trace width can complicate the design and manufacturing process, especially in areas where traces converge near connector joints.

[0073] Improved efficiency: By ensuring impedance balance, one or more embodiments minimize energy loss due to heat generated by non-uniform resistance in the traces. This improves the overall energy efficiency of battery 104. Existing methods that fail to achieve precise impedance matching can result in higher energy loss, thus reducing battery efficiency.

[0074] Enhanced Reliability: Impedance imbalance can lead to uneven heating and potential hot spots within battery 104, increasing the risk of thermal runaway. One or more embodiments mitigate this risk by ensuring uniform impedance across the trace, resulting in a more uniform temperature distribution. Existing methods that cannot achieve precise impedance matching may increase the likelihood of thermal problems, thereby compromising the reliability of the battery pack.

[0075] Flexibility and scalability: One or more embodiments can be adapted to a variety of battery configurations, including different numbers of battery cells and battery cell types (e.g., prismatic or cylindrical battery cells). This flexibility allows one or more embodiments described herein to be applicable to a wide range of high-voltage battery designs. Existing methods that rely on varying trace widths may not be easily adapted to different battery configurations.

[0076] These and other benefits are possible in the various embodiments described herein.

[0077] It should be understood that one or more embodiments described herein can be implemented in conjunction with any other type of computing environment now known or developed in the future. For example, Figure 6 A block diagram of a processing system 600 for implementing the techniques described herein is depicted. According to one or more embodiments described herein, the processing system 600 is an example of a cloud computing node in a cloud computing environment. In the example, the processing system 600 has one or more central processing battery units (also referred to as “processors”, “processing resources”, or “processing devices”) 621a, 621b, 621c, etc. (collectively or generally referred to as processor 621 and / or processing device 621). In aspects of this disclosure, each processor 621 may include a Reduced Instruction Set Computer (RISC) microprocessor. The processor 621 is coupled to system memory 622 and / or various other components via a system bus 633. System memory 622 may include one or more temporary and / or permanent memory devices, such as random access memory (RAM) 623, read-only memory (ROM) 624, etc., including combinations and / or multiple such devices. System bus 633 may include a Basic Input / Output System (BIOS) that controls certain basic functions of the processing system 600.

[0078] Further depictions include an input / output (I / O) adapter 627 and a network adapter 626 connected to the system bus 633. The I / O adapter 627 may be a Small Computer System Interface (SCSI) adapter that communicates with a hard disk 635 and / or storage device 636 or any other similar component. The I / O adapter 627, hard disk 635, and storage device 636 are collectively referred to herein as mass storage 634. An operating system 640 for execution on the processing system 600 may be stored in the mass storage 634. The network adapter 626 interconnects the system bus 633 with an external network 638, enabling the processing system 600 to communicate with other such systems.

[0079] A display (e.g., a display monitor) 639 is connected to the system bus 633 via a display adapter 632, which may include a graphics adapter to improve the performance of graphics-intensive applications and video controllers. In one aspect of this disclosure, adapters 626, 627, and / or 632 may be connected to one or more I / O buses connected to the system bus 633 via an intermediate bus bridge (not shown). Suitable I / O buses for connecting peripheral devices such as hard disk controllers, network adapters, and graphics adapters typically include common protocols such as Peripheral Component Interconnect (PCI). Additional input / output devices are shown connected to the system bus 633 via a user interface adapter 628 and the display adapter 632. A keyboard 629, a mouse 630, and a speaker 631 may be interconnected to the system bus 633 via a user interface adapter 628, which may include, for example, a super I / O chip integrating multiple device adapters into a single integrated circuit.

[0080] In some aspects of this disclosure, the processing system 600 includes a graphics processing unit (GPU) 637. The GPU 637 is a dedicated electronic circuit designed to manipulate and modify memory to accelerate the creation of images intended for output to a frame buffer for a display. Typically, the GPU 637 is highly efficient in manipulating computer graphics and image processing and has a highly parallel architecture that makes it more efficient than a general-purpose CPU for algorithms that process large blocks of data in parallel.

[0081] Therefore, as configured herein, the processing system 600 includes processing power in the form of a processor 621, storage capacity including system memory 622 and mass storage 634, input devices such as a keyboard 625 and a mouse 630, and output capacity including a speaker 631 and a display 639. In some aspects of this disclosure, a portion of the system memory 622 and the mass storage 634 jointly store an operating system 640 to coordinate the functions of the various components shown in the processing system 600.

[0082] The terms “a” and “an” do not indicate a limitation of quantity, but rather that at least one of the referenced items is present. Unless the context clearly indicates otherwise, the term “or” means “and / or”. Throughout the specification, the reference to “aspect” means that a particular element described in connection with that aspect (e.g., a feature, structure, step, or characteristic) is included in at least one aspect described herein and may or may not be present in other aspects. Furthermore, it should be understood that the described elements may be combined in any suitable manner in the aspects.

[0083] When an element, such as a layer, film, region, or substrate, is referred to as being “on” another element, it can be directly on the other element, or there may be intermediate elements present. Conversely, when an element is referred to as being “directly” on another element, there are no intermediate elements present.

[0084] Unless otherwise specified herein, all test standards are the most recent standards in effect up to the filing date of this application, or, if priority is claimed, the filing date of the earliest priority application in which a test standard appears.

[0085] Unless otherwise defined, the technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0086] While the foregoing disclosure has been described with reference to exemplary embodiments, those skilled in the art will understand that various changes can be made and elements can be substituted with equivalents without departing from its scope. Furthermore, many modifications can be made to adapt particular situations or materials to the teachings of this disclosure without departing from the basic scope of this disclosure. Therefore, this disclosure is intended to be limited to the specific embodiments disclosed, but will include all embodiments falling within its scope.

Claims

1. A computer-implemented method for impedance balancing in a monitoring circuit for a vehicle battery, the method comprising: Calculate the resistance values ​​of multiple traces of the monitoring circuit, which electrically connects the battery to the battery cell monitoring unit, wherein the battery comprises multiple battery cells; Determine the maximum trace resistance value among multiple trace resistance values; Calculate the difference between the maximum trace resistance value and each of the plurality of trace resistance values; Each trace in a subset of traces with trace resistance values ​​greater than the threshold resistance is identified; and A resistor is added to each of a subset of traces that have a trace resistance value greater than the threshold resistance.

2. The computer-implemented method of claim 1, wherein the resistance value of the resistor added to a subset of traces having trace resistance values ​​with the difference greater than the threshold resistance is at least partially based on the difference being greater than the threshold resistance.

3. The computer-implemented method of claim 1, wherein the resistor is selected from a group of resistors having predefined resistance values.

4. The computer-implemented method of claim 3, wherein the resistor is selected from the set of resistors having predefined resistance values ​​based at least in part on the difference being greater than a threshold resistance.

5. The computer-implemented method according to claim 1, wherein the resistor is a surface mount device resistor.

6. The computer-implemented method according to claim 1, wherein the battery is a rechargeable battery.

7. The computer-implemented method according to claim 1, further comprising: Determine the minimum resistance change for each of the multiple traces; Determine the maximum resistance change for each of the multiple traces; For each trace in a subset of traces with trace resistance values ​​greater than the threshold resistance, after adding the resistor to the monitoring circuit, the updated trace resistance values ​​for the multiple traces are calculated. and Verify that the updated resistance values ​​of multiple traces are within the range defined by the minimum and maximum resistance changes.

8. The computer-implemented method of claim 1, wherein the traces among the plurality of traces have substantially equal widths and substantially equal thicknesses.

9. The computer-implemented method of claim 1, wherein the traces among the plurality of traces have varying lengths.

10. A processing system for performing impedance balancing of a monitoring circuit for a vehicle battery, the processing system comprising: Memory including computer-readable instructions; and A processing apparatus for executing the computer-readable instructions, the computer-readable instructions controlling the processing system to perform operations, including: Calculate the resistance values ​​of multiple traces of the monitoring circuit, which electrically connects the battery to the battery cell monitoring unit, wherein the battery comprises multiple battery cells; Determine the maximum trace resistance value among multiple trace resistance values; Calculate the difference between the maximum trace resistance value and each of the plurality of trace resistance values; Each trace in a subset of traces having a trace resistance value greater than the threshold resistance is identified; and Identify the resistor to be added to each trace in a subset of traces that have a trace resistance value greater than the threshold resistance.

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