Cell tolerance processing method, battery management system and storage medium
By monitoring the real-time cell voltage and current during the battery pack charging process, the actual charging capacity between cells is calculated, solving the problem of low data accuracy due to differences in battery pack contents. This achieves more effective battery pack balancing, extends battery pack lifespan, and improves safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ECOFLOW INC
- Filing Date
- 2025-06-25
- Publication Date
- 2026-05-12
AI Technical Summary
In existing technologies, the accuracy of tolerance data calculation between cells within a battery pack is low, leading to battery pack performance degradation and safety hazards. Furthermore, existing balancing strategies are inefficient.
By monitoring the real-time cell voltage and current during the battery pack charging process, the first and second moments are determined, and the actual charging capacity of each cell during this period is calculated as tolerance data to improve the accuracy of the calculation. Based on the tolerance data, the cells to be balanced are determined and tolerance balancing is performed.
It improves the accuracy of tolerance data calculation, optimizes the battery pack balancing strategy, and extends the battery pack's lifespan and safety.
Smart Images
Figure CN122025868A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of battery technology, and in particular to a cell tolerance processing method, a battery management system, and a storage medium. Background Technology
[0002] During charge-discharge cycles, differences in manufacturing parameters, dispersion, material aging characteristics, and operating temperature distribution among individual battery cells can lead to variations in parameters such as voltage, capacity, and temperature. As the number of cycles increases, this parameter inconsistency accumulates and amplifies, causing some cells to enter overcharge or over-discharge states. This problem not only accelerates the overall performance degradation of the battery pack but can also trigger safety hazards such as thermal runaway in severe cases, significantly limiting the battery pack's lifespan and reliability.
[0003] To improve battery pack consistency, increase usable capacity, and extend lifespan, balancing methods are needed to eliminate inconsistencies in the capacity of battery cells. However, tolerance balancing relies on tolerance data, which is typically estimated based on voltage differences between cells, resulting in relatively low accuracy. Summary of the Invention
[0004] In view of the above, it is necessary to provide a cell tolerance processing method, a battery management system and a storage medium to solve the problem of low accuracy in tolerance data calculation.
[0005] This application provides a cell tolerance processing method. During battery pack charging, the real-time cell voltage and real-time cell current of each cell in the battery pack are monitored. When the maximum value of each real-time cell voltage rises to a first voltage threshold, a first moment is determined. The minimum value of each real-time cell voltage is obtained. Based on historical voltage monitoring data of the real-time cell voltage corresponding to each cell, a second moment when the real-time cell voltage corresponding to each cell reaches the minimum value is determined. The second moment is earlier than or equal to the first moment. Based on historical current monitoring data of the real-time cell current corresponding to each cell, the charging amount of each cell during the period from the corresponding second moment to the first moment is calculated to obtain the tolerance data corresponding to each cell.
[0006] The cell tolerance processing method disclosed in this application can determine a first moment when the maximum value of each real-time cell voltage first rises to a first voltage threshold, and determine the lowest cell voltage corresponding to this first moment. This allows for the determination of a second moment when the cell has historically been charged to its lowest voltage. The actual charging capacity of each cell is calculated based on the current between the first and second moments, and this charging capacity is used as tolerance data. Compared to existing methods that estimate tolerance data based on the voltage difference between individual cells, this method effectively improves the accuracy of the calculated tolerance data.
[0007] This application also provides a cell tolerance processing device, which includes: a monitoring module for monitoring the real-time cell voltage and real-time cell current of each cell in the battery pack during battery pack charging; a determination module for determining a first moment when the maximum value of each real-time cell voltage rises to a first voltage threshold; an acquisition module for acquiring the minimum value of each real-time cell voltage; the determination module is further used to determine a second moment when the real-time cell voltage of each cell reaches the minimum value based on historical voltage monitoring data of the real-time cell voltage of each cell; the second moment is earlier than or equal to the first moment; and a processing module for calculating the charging amount of each cell during the period from the corresponding second moment to the first moment based on historical current monitoring data of the real-time cell current of each cell, thereby obtaining the tolerance data of each cell.
[0008] This application also provides a battery management system electrically connected to a battery pack. The battery management system includes: at least one processor; and a memory communicatively connected to the at least one processor, wherein the memory stores instructions executed by the at least one processor to enable the at least one processor to perform the cell tolerance processing method as described above.
[0009] This application also provides a computer-readable storage medium storing computer-readable instructions that are executed by a processor in a battery management system to implement a cell tolerance processing method. Attached Figure Description
[0010] Figure 1 This is a flowchart of a cell tolerance processing method provided in an embodiment of this application.
[0011] Figure 2 This is a flowchart of a cell tolerance processing method provided in another embodiment of this application.
[0012] Figure 3 This is a schematic diagram of the structure of a battery management system provided in an embodiment of this application.
[0013] Figure 4This is a schematic diagram of the structure of an energy storage device provided in one embodiment of this application.
[0014] Figure 5 This is a schematic diagram of the structure of a cell tolerance processing device provided in an embodiment of this application. Detailed Implementation
[0015] For ease of understanding, some concepts related to the embodiments of this application are illustrated and explained by way of example for reference.
[0016] It should be noted that the terms "first", "second", "third", "fourth", "fifth", etc. (if present) in the specification, claims and drawings of this application are used to distinguish similar objects, rather than to describe a specific order or sequence.
[0017] During use, inconsistencies between internal parameters of battery cells and external environmental parameters can lead to differences in voltage, capacity, temperature, and other parameters among the cells within a battery pack (e.g., lithium-ion battery packs). Furthermore, over time, these inconsistencies may amplify, causing some cells to enter overcharge or over-discharge states. This problem not only accelerates the overall performance degradation of the battery pack but can also trigger safety hazards such as thermal runaway in severe cases, significantly limiting the battery pack's lifespan and reliability.
[0018] To improve battery pack consistency, increase usable capacity, and extend cycle life, balancing techniques are needed to address capacity inconsistencies among individual cells. Currently, small-scale energy storage systems typically employ passive balancing strategies, primarily based on differential voltage balancing. However, considering the platform characteristics of the battery pack and the limited duration of the charging end interval, differential voltage balancing is generally inefficient. Therefore, a tolerance-based balancing strategy that can initiate balancing during the discharge phase offers a significant advantage in efficiency. However, tolerance balancing relies on tolerance data, which is usually estimated based on the voltage difference between cells, resulting in relatively low accuracy.
[0019] To address the aforementioned issues, this application provides a cell tolerance processing method that can calculate a first moment to determine the lowest cell voltage, thereby determining a second moment when the cell was historically charged to the lowest cell voltage. The actual charging capacity is then calculated based on the current between the first and second moments as tolerance data, thus improving the accuracy of the calculated tolerance data.
[0020] Figure 1 This is a flowchart of a cell tolerance processing method provided in an embodiment of this application, as shown below. Figure 1As shown, the cell tolerance handling method is applied in energy storage devices. Depending on different requirements, the order of the steps in this flowchart can be changed, and some steps can be omitted.
[0021] Step S01: During battery pack charging, monitor the real-time cell voltage and real-time cell current of each cell in the battery pack.
[0022] In some embodiments of this application, during the charging process of a battery cell (e.g., a lithium iron phosphate battery), each cell in the battery pack corresponds to a charging curve, which includes a plateau range and a non-plateau range. When the voltage of a cell transitions from the plateau range to the non-plateau range, the voltage tends to rise rapidly. If the cells in the battery pack are not identical, the cells with higher capacity will transition from the plateau range to the non-plateau range first. The voltage difference between the higher-capacity cells and other cells still in the plateau range will become increasingly larger, and the capacity difference between the cells will also increase. The later the lower-capacity cells transition from the plateau range to the non-plateau range, the greater the voltage difference between them and the cells that transitioned first. By using the charging terminal voltage curves corresponding to the voltages of different cells in the non-plateau range, the capacity difference between different cells can be approximately estimated.
[0023] In one embodiment, to allow for greater charge, current limiting can be implemented at the end of the battery pack charging process; that is, the battery pack charging nodes include a current-limited charging phase. Tolerance calculations can be performed before entering the current-limited charging phase.
[0024] Therefore, during battery pack charging, it is necessary to monitor the real-time cell voltage and real-time cell current of each cell in the battery pack, so as to determine the timing for calculating the tolerance data between each cell based on the real-time cell voltage and real-time cell current of each cell.
[0025] Step S02: When the maximum value of each real-time cell voltage rises to the first voltage threshold, the first moment is determined.
[0026] In some embodiments of this application, during the charging process of the battery pack, the real-time cell voltage of each cell in the battery pack is monitored, and when the voltage of the cell corresponding to the maximum value among the real-time cell voltages first rises to a first voltage threshold (e.g., set to 3450mV), the first time t0 is determined.
[0027] In some embodiments of this application, the first voltage threshold is less than or equal to the starting voltage of the current-limited charging phase.
[0028] Step S03: Obtain the minimum value among the real-time cell voltages.
[0029] In some embodiments of this application, in order to calculate the tolerance between individual cells, it is necessary to determine the minimum value among the real-time cell voltages. For example, at the first time t0, the minimum value among the real-time cell voltages is determined.
[0030] Step S04: Based on the historical voltage monitoring data of the real-time cell voltage corresponding to each cell, determine the second moment when the real-time cell voltage corresponding to each cell reaches the minimum value.
[0031] In some embodiments of this application, after determining the minimum value among the real-time cell voltages, it is also necessary to determine the second time t1 at which the real-time cell voltage for each cell reaches the minimum value. Specifically, based on historical voltage monitoring data of the real-time cell voltages for each cell, the second time t1 at which the real-time cell voltage for each cell reaches the minimum value is determined respectively. The second time t1 for different cells may be partially the same or may be different for each cell.
[0032] In the embodiments of this application, the second moment is earlier than or equal to the first moment.
[0033] In this embodiment, the real-time cell voltage of each cell can be monitored and stored during the charging process of the battery pack to obtain historical voltage monitoring data. Alternatively, historical voltage monitoring data of the real-time cell voltage of each cell can be received from an electronic device.
[0034] Step S05: Based on the historical current monitoring data of the real-time cell current corresponding to each cell, calculate the charging capacity of each cell during the period from the second time to the first time, and obtain the tolerance data corresponding to each cell.
[0035] In some embodiments of this application, to avoid the impact of depolarization, when calculating the tolerance data for each cell, the tolerance data can be calculated during the charging phase between when each cell leaves the plateau region and transitions to the non-plateau region, but before reaching the current-limited charging phase. Specifically, based on the historical current monitoring data of the real-time cell current for each cell, the charging capacity of each cell during the period from the corresponding second time point to the first time point can be calculated to obtain the tolerance data for each cell.
[0036] In this embodiment, the real-time cell current of each cell can be monitored in real time during the charging process of the battery pack to obtain historical current monitoring data. Alternatively, historical current monitoring data of the real-time cell current of each cell can be received from an electronic device.
[0037] Through the above steps S01 to S05, a first moment can be determined when the maximum value of each real-time cell voltage first rises to the first voltage threshold, and the lowest cell voltage corresponding to the first moment can be determined, thereby determining the second moment when the cell was historically charged to the lowest cell voltage.
[0038] Specifically, it can be assumed that battery cells with the same or similar specifications have similar charge levels when they reach the same cell voltage. Therefore, for each cell in the battery pack, it can be assumed that the charge level of these cells at the corresponding second time point is the same as or similar to the charge level of the cell with the lowest cell voltage at the first time point.
[0039] Afterwards, these cells will continue to charge during the period between the second moment and the first moment. Therefore, the difference in charge between these cells and the cell with the lowest cell voltage corresponding to the first moment (i.e., the tolerance data) is the charge charge of these cells during the period between the second moment and the first moment.
[0040] Therefore, in this embodiment of the application, the actual charging capacity of each cell can be calculated based on the historical current monitoring data between the first and second time points, and this charging capacity can be used as tolerance data.
[0041] Compared with the existing technology that estimates tolerance data based on the voltage difference between individual cells, this application uses the actual charging capacity of each cell from the second moment to the first moment as the capacity data, which can effectively improve the accuracy of the calculated tolerance data.
[0042] Figure 2 This is a flowchart of a cell tolerance processing method provided in another embodiment of this application, such as... Figure 2 As shown, the cell tolerance handling method is applied in energy storage devices. Depending on different requirements, the order of the steps in this flowchart can be changed, and some steps can be omitted.
[0043] Step S21: When the battery pack is charging, monitor the real-time cell voltage and real-time cell current of each cell in the battery pack.
[0044] Step S22: When the maximum value of each real-time cell voltage rises to the first voltage threshold, the first moment is determined.
[0045] Step S23: Obtain the minimum value among the real-time cell voltages.
[0046] Step S24: Based on the historical voltage monitoring data of the real-time cell voltage corresponding to each cell, determine the second moment when the real-time cell voltage corresponding to each cell reaches the minimum value.
[0047] Step S25: Based on the historical current monitoring data of the real-time cell current corresponding to each cell, calculate the charging capacity of each cell during the period from the second time to the first time, and obtain the tolerance data corresponding to each cell.
[0048] The specific implementation methods for steps S21 to S25 can all be referred to Figure 1The implementation methods of S01 to S05 are not described in detail here.
[0049] Step S26: Based on the tolerance data corresponding to each cell, determine the cells to be balanced.
[0050] In some embodiments of this application, after obtaining the tolerance data corresponding to each cell, the cell to be balanced can be determined based on the tolerance data corresponding to each cell.
[0051] In some embodiments of this application, the cells to be balanced are determined based on the tolerance data corresponding to each cell, including: identifying the N cells with the largest tolerance data as the cells to be balanced, where N is a preset positive integer. For example, in one example, assuming the battery pack includes sixteen cells, the nine cells with the largest tolerance data can be identified as the cells to be balanced.
[0052] In some embodiments of this application, determining the cells to be balanced based on the tolerance data corresponding to each cell further includes: determining that there are no cells to be balanced when the maximum tolerance data is less than a first tolerance threshold.
[0053] If the tolerance data corresponding to each cell is less than the first tolerance threshold, it is determined that the capacity difference between the cells is small and there is no need to perform capacity balancing. It is determined that there are no cells to be balanced. If some or all of the tolerance data corresponding to each cell is greater than or equal to the first tolerance threshold, it is determined that the capacity difference between the cells is large and capacity balancing is required. The N cells with the largest tolerance data can be identified as cells to be balanced, where N is a preset positive integer.
[0054] The first tolerance threshold can be set according to the needs of the actual scenario. For example, in some scenarios, 1%, 2%, or other values of the rated capacity of the battery cell can be set as the first tolerance threshold.
[0055] Step S27: Perform tolerance balancing on the cells to be balanced.
[0056] In this embodiment of the application, after determining the cell to be balanced, tolerance balancing can be performed on the cell.
[0057] In some embodiments of this application, the tolerance equalization of the cells to be equalized further includes: obtaining a target equalization capacity, and performing tolerance equalization on the cells to be equalized based on the target equalization capacity.
[0058] To prevent over-balancing when determining the cells to be balanced, a progressively adaptive approximation strategy can be used to perform tolerance balancing. For example, in some embodiments, obtaining the target balancing capacity includes: when the tolerance data corresponding to the cell to be balanced is less than or equal to a second tolerance threshold, determining the tolerance data corresponding to the cell to be balanced as the target balancing capacity; when the tolerance data corresponding to the cell to be balanced is greater than the second tolerance threshold, determining the second tolerance threshold as the target balancing capacity. This method ensures that the capacity of each balancing operation is less than or equal to the second tolerance threshold, avoiding over-balancing.
[0059] One round of tolerance balancing can be considered as calculating tolerance data once and performing tolerance balancing once.
[0060] After the first round of tolerance balancing of the cells to be balanced, the tolerance data of each cell can be recalculated during the next charge if the tolerance calculation conditions are met. If the tolerance data of each cell is still partially or entirely greater than or equal to the first tolerance threshold, then the cells to be balanced are re-determined and tolerance balancing is performed on them.
[0061] Then, the next round of tolerance balancing begins until the capacity difference between each cell is less than the first tolerance threshold, at which point it is determined that there are no cells left to be balanced.
[0062] The second tolerance threshold can be set according to the needs of the actual scenario. For example, in some scenarios, 1%, 2%, or other values of the rated capacity of the battery cell can be set as the second tolerance threshold.
[0063] Through the above steps S21 to S27, a first moment can be determined when the maximum value of each real-time cell voltage first rises to the first voltage threshold, and the lowest cell voltage corresponding to the first moment can be determined. In this way, a second moment when the cell was charged to the lowest cell voltage in history can be determined. The actual charging capacity of each cell can be calculated based on the current between the first moment and the second moment, and the charging capacity can be used as tolerance data. Based on the tolerance data corresponding to each cell, the cell to be balanced can be determined, and tolerance balancing can be performed on the cell to be balanced.
[0064] In addition, when performing tolerance balancing, a better balancing effect can be achieved gradually by using a method of small amounts and multiple times, while avoiding deviations caused by abnormal tolerance data calculations in a single instance, thus improving the robustness of tolerance data calculation and balancing effect.
[0065] In one embodiment of this application, the battery pack includes sixteen cells, namely cell 1, cell 2... cell 16. Using the cell tolerance processing method provided in this application, a first moment can be determined when the maximum value of each real-time cell voltage first rises to a first voltage threshold, and the lowest cell voltage corresponding to this first moment can be determined. This, in turn, determines a second moment when the cell has historically been charged to its lowest cell voltage. The actual charging capacity of each cell is calculated based on the current between the first and second moments, and this charging capacity is used as tolerance data, as shown in Table 1 below. The calculation results show that cell 9 has the largest capacity difference with the lowest cell voltage, with a tolerance data of 2361mAh. Except for cell 9, the cell balancing priority is, in order, cell 8, cell 6, cell 7, and cell 10.
[0066] Table 1 If tolerance estimation is performed based on the individual cell voltages when the battery pack is fully charged, the cell voltage distribution at full charge is shown in Table 2. Table 2 shows that cell 14 has the highest voltage. During battery charging, as the battery pack approaches full charge (the end of charging), the voltage differences between cells are amplified. This is mainly due to slight differences in cell capacity, internal resistance, or aging. Cells with higher voltages (such as cells 14 and 12) may indicate smaller actual capacity, higher internal resistance, or more severe aging. These cells will reach their voltage limit (e.g., 4.2V or similar) faster under the same charging current, triggering the battery management system (BMS)'s charging termination protection to prevent overcharging. Cells with lower voltages (such as cells 1 and 2) indicate larger capacity or better condition, requiring longer to fully charge. If high-voltage cells are not balanced, the charging process will end prematurely, preventing low-voltage cells from fully charging, thus reducing the overall usable capacity and efficiency of the battery pack. Therefore, based on the voltage distribution at the end of charging, cells 11 to 16 are prioritized for balancing. It is known that the battery pack's equalization judgment may be biased due to the influence of cell depolarization. If the capacity difference between cells is estimated based on the voltage after depolarization, the cells will be incorrectly equalized.
[0067] Table 2 Figure 3 A schematic structural block diagram of a battery management system 101 provided in the second aspect of an embodiment of this application is shown. For ease of explanation, only the parts related to the embodiment of this application are shown.
[0068] Reference Figure 3The battery management system 101 is installed in the energy storage device and is connected to the battery pack 102 of the energy storage device. The battery management system 101 includes a memory 1012, a processor 1011 and a computer program stored in the memory 1012 and executable on the processor 1011. When the processor 1011 executes the computer program, it implements the cell tolerance processing method described above.
[0069] The memory 1012 may include one or more random access memory (RAM) and one or more non-volatile memory (NVM). The RAM can be directly read and written by the processor 1011, and can be used to store executable programs (such as machine instructions) of the operating system or other running programs, as well as user and application data.
[0070] Random access memory can include static random-access memory (SRAM), dynamic random-access memory (DRAM), synchronous dynamic random-access memory (SDRAM), double data rate synchronous dynamic random-access memory (DDR SDRAM), etc.
[0071] Non-volatile memory can also store executable programs and user and application data, and can be pre-loaded into random access memory for direct reading and writing by the processor 1011. Non-volatile memory can include disk storage devices and flash memory.
[0072] The memory 1012 is used to store one or more computer programs. The one or more computer programs are configured to be executed by the processor 1011. The one or more computer programs include multiple instructions that, when executed by the processor 1011, can implement a cell tolerance processing method executed on the battery management system 101.
[0073] The processor 1011 may include one or more processing units, such as an application processor (AP), a modem processor, a graphics processing unit (GPU), an image signal processor (ISP), a controller, a video codec, a digital signal processor (DSP), a baseband processor, and / or a neural network processing unit (NPU). These different processing units may be independent devices or integrated into one or more processors.
[0074] The processor 1011 provides computing and control capabilities. For example, the processor 1011 is used to execute computer programs stored in the memory 1012 to implement the above-described cell tolerance processing method.
[0075] Figure 4 A schematic structural block diagram of an energy storage device 10 provided in the third aspect of an embodiment of this application is shown. For ease of explanation, only the parts related to the embodiments of this application are shown.
[0076] Reference Figure 4 The energy storage device 10 includes a battery management system 101 and a battery pack 102. The battery management system 101 is connected to the battery module 102. When executing a computer program, the battery management system 101 implements the cell tolerance processing method described above.
[0077] Figure 5 A schematic structural block diagram of the cell tolerance processing apparatus 20 provided in the fourth aspect of the present application is shown, as follows: Figure 5 As shown in this embodiment, the cell tolerance processing device 20 can be divided into multiple functional modules according to the functions it performs. These functional modules may include: a monitoring module 201, a determination module 202, an acquisition module 203, and a processing module 204.
[0078] The monitoring module 201 is used to monitor the real-time cell voltage and real-time cell current of each cell in the battery pack during battery pack charging. The determination module 202 is used to determine the first moment when the maximum value of each real-time cell voltage rises to a first voltage threshold. The acquisition module 203 is used to acquire the minimum value among the real-time cell voltages; The determining module 202 is also used to determine the second moment when the real-time cell voltage of each cell reaches the minimum value based on the historical voltage monitoring data of the real-time cell voltage corresponding to each cell; the second moment is earlier than or equal to the first moment. The processing module 204 is used to calculate the charging capacity of each cell from the second moment to the first moment based on the historical current monitoring data of the real-time cell current corresponding to each cell, and obtain the tolerance data corresponding to each cell.
[0079] In some embodiments, the processing module 204 is further configured to determine the cells to be balanced based on the tolerance data corresponding to each cell; and to perform tolerance balancing on the cells to be balanced.
[0080] In some embodiments, the processing module 204 is further configured to determine the N cells with the largest tolerance data as cells to be balanced, where N is a preset positive integer.
[0081] In some embodiments, the determining module 202 is further configured to determine that there are no cells to be balanced when the maximum tolerance data is less than the first tolerance threshold.
[0082] In some embodiments, the acquisition module 203 is further configured to acquire the target equalization capacity; the processing module 204 is further configured to perform tolerance equalization on the cells to be equalized based on the target equalization capacity.
[0083] In some embodiments, the processing module 204 is further configured to determine the tolerance data corresponding to the cell to be balanced as the target balancing capacity when the tolerance data corresponding to the cell to be balanced is less than or equal to the second tolerance threshold.
[0084] In some embodiments, the processing module 204 is further configured to determine the second tolerance threshold as the target equalization capacity when the tolerance data corresponding to the cell to be equalized is greater than the second tolerance threshold.
[0085] In some embodiments, the processing module 204 is further configured to include a current-limited charging phase in the charging phase of the battery pack, wherein a first voltage threshold is less than or equal to the starting voltage of the current-limited charging phase.
[0086] It should be noted that the information interaction and execution process between the above-mentioned devices / units / modules are based on the same concept as the method embodiments of this application. For details on their specific functions and technical effects, please refer to the method embodiments section, and they will not be repeated here.
[0087] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.
[0088] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include at least: any entity or device capable of carrying computer program code to a photographing device / terminal device, a recording medium, a computer memory, a read-only memory (ROM), a random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media. Examples include USB flash drives, portable hard drives, magnetic disks, or optical disks. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electrical carrier signals and telecommunication signals.
[0089] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.
[0090] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.
[0091] In the embodiments provided in this application, it should be understood that the disclosed apparatus / network devices and methods can be implemented in other ways. For example, the apparatus / network device embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.
[0092] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.
[0093] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.
Claims
1. A method for handling battery cell tolerance, characterized in that, The method includes: During battery pack charging, monitor the real-time cell voltage and real-time cell current of each cell in the battery pack. When the maximum value of each of the real-time cell voltages rises to a first voltage threshold, a first moment is determined; Obtain the minimum value among the real-time cell voltages described above; Based on historical voltage monitoring data of the real-time cell voltage corresponding to each of the aforementioned cells, the second time when the real-time cell voltage corresponding to each of the aforementioned cells reaches the minimum value is determined; the second time is earlier than or equal to the first time. Based on the historical current monitoring data of the real-time cell current corresponding to each of the cells, the charging capacity of each cell during the period from the second time to the first time is calculated to obtain the tolerance data corresponding to each cell.
2. The method as described in claim 1, characterized in that, The method further includes: Based on the tolerance data corresponding to each of the aforementioned cells, the cells to be balanced are determined. Tolerance balancing is performed on the cells to be balanced.
3. The method as described in claim 2, characterized in that, The step of determining the cells to be balanced based on the tolerance data corresponding to each of the cells includes: The N cells with the largest tolerance data are identified as cells to be balanced, where N is a preset positive integer.
4. The method as described in claim 2, characterized in that, The step of determining the cells to be balanced based on the tolerance data corresponding to each of the cells further includes: When the maximum tolerance data is less than the first tolerance threshold, it is determined that there are no cells to be balanced.
5. The method as described in claim 2, characterized in that, The method further includes: Obtain the target balanced capacity; The tolerance balancing of the cells to be balanced includes: Based on the target equalization capacity, tolerance equalization is performed on the cells to be equalized.
6. The method as described in claim 5, characterized in that, The process of obtaining the target balanced capacity includes: When the tolerance data corresponding to the cell to be balanced is less than or equal to the second tolerance threshold, the tolerance data corresponding to the cell to be balanced is determined as the target balancing capacity.
7. The method as described in claim 5, characterized in that, The process of obtaining the target balanced capacity includes: When the tolerance data corresponding to the cell to be balanced is greater than the second tolerance threshold, the second tolerance threshold is determined as the target balancing capacity.
8. The method as described in claim 1, characterized in that, The charging phase of the battery pack includes a current-limited charging phase, wherein the first voltage threshold is less than or equal to the starting voltage of the current-limited charging phase.
9. A battery management system, wherein the battery management system is electrically connected to a battery pack, characterized in that, The battery management system includes: At least one processor; and, A memory communicatively connected to the at least one processor, wherein the memory stores instructions that are executed by the at least one processor to enable the at least one processor to perform the cell tolerance processing method as described in any one of claims 1 to 8.
10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-readable instructions, which are executed by a processor in the battery management system to implement the cell tolerance processing method as described in any one of claims 1 to 8.