Self-discharge detection method, self-discharge detection device, storage medium, and self-discharge detection system
By obtaining the number of usable and effective equalization cycles of the cells during battery pack equalization and calculating the degree of self-discharge, the problem of time-consuming and labor-intensive traditional detection methods is solved, and real-time monitoring and early identification of cell self-discharge are realized.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- EVE ENERGY CO LTD
- Filing Date
- 2025-09-04
- Publication Date
- 2026-07-21
AI Technical Summary
Traditional self-discharge detection methods are time-consuming and labor-intensive, making it difficult to achieve accurate and real-time detection, and unable to detect self-discharge anomalies during battery pack operation.
During each battery pack equalization, the available equalization times and effective equalization times of the cells are obtained, and the self-discharge level is calculated through weighting coefficients to determine self-discharge anomalies in real time.
It enables real-time monitoring of cell self-discharge levels, simplifies the testing process, improves testing efficiency, reduces costs and time, and enhances the ability to identify abnormal cells at an early stage.
Smart Images
Figure CN120870913B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of battery technology, and in particular to a self-discharge detection method, self-discharge detection equipment, storage medium, and self-discharge detection system. Background Technology
[0002] With the widespread adoption of modern electronic devices and the rapid development of electric vehicles, rechargeable cells such as lithium-ion batteries have become a widely used energy storage solution. The performance and reliability of these cells directly impact the lifespan of devices and the user experience. Among the various performance indicators of cells, self-discharge rate is a key factor. Self-discharge refers to the decrease in cell voltage over time. A high self-discharge rate not only reduces the energy storage efficiency of the cell but may also lead to excessive power consumption and a shortened lifespan of the device.
[0003] Traditional self-discharge detection methods typically rely on long-term static observation and complex instruments, which are not only time-consuming and labor-intensive but also difficult to implement with precise control and real-time detection in practical applications. Therefore, there is an urgent need for a method that can quickly and accurately detect abnormal self-discharge in battery cells to improve cell utilization efficiency and safety. Summary of the Invention
[0004] This application provides a self-discharge detection method, self-discharge detection equipment, storage medium, and self-discharge detection system to promptly detect abnormal self-discharge problems in battery cells.
[0005] The technical solution adopted in this application is as follows.
[0006] In a first aspect, this application provides a self-discharge detection method, comprising: during each equalization of the battery pack, for each cell in the battery pack, obtaining the number of available equalization times and the number of effective equalization times for each cell; calculating the self-discharge degree of the cell based on the number of available equalization times and the number of effective equalization times; and determining the cell as a cell with abnormal self-discharge when the self-discharge degree of the cell meets a preset self-discharge condition.
[0007] This application enables real-time acquisition of the available and effective equalization times of each cell during battery pack equalization, thereby achieving real-time monitoring of the cell's self-discharge level. By utilizing existing data from the cell equalization process, it eliminates the need for additional complex measurement equipment and prolonged static observation, simplifying the detection process and improving detection efficiency. Furthermore, this method can detect self-discharging cells in real-time via software during cell operation, facilitating user replacement and reducing the cost and cycle time for detecting cell self-discharge.
[0008] In conjunction with the first aspect, in one possible implementation, the method further includes: obtaining the available balancing count of the battery cell, including: increasing the available balancing count of the battery cells that have not been balanced in this balancing process by one.
[0009] This application dynamically tracks the number of times each cell can be balanced by recording and counting the cells that are not balanced during each balancing process. This continuously updated mechanism reflects the specific state changes of the cells during use, providing a more comprehensive understanding of the cell's health status.
[0010] In conjunction with the first aspect, in one possible implementation, the method further includes: obtaining the effective balancing count of the battery cell, including: increasing the effective balancing count of the only battery cell that did not start balancing in this balancing process by one.
[0011] This application enables comprehensive monitoring of a battery cell's performance during the equalization process by simultaneously recording both the available equalization counts and the effective equalization counts. Recording the effective equalization counts reveals frequencies that were not adjusted during multiple equalization processes. A high cumulative number of effective equalization counts may indicate abnormal self-discharge within the battery cell, thereby enhancing the system's ability to identify and diagnose abnormal cells at an early stage.
[0012] In conjunction with the first aspect, in one possible implementation, the self-discharge level of the battery cell is positively correlated with both the available balancing times and the effective balancing times.
[0013] This application establishes a positive correlation between the degree of self-discharge and the number of available equalization cycles and the number of effective equalization cycles, enabling a more accurate identification of the cell's self-discharge trend. This correlation provides a quantitative indicator, allowing the battery management system to monitor and evaluate the cell's health status in real time.
[0014] In conjunction with the first aspect, in one possible implementation, the self-discharge level of the battery cell is calculated based on the available balancing counts and the effective balancing counts, including: calculating a first discharge level by using the available balancing counts according to an assigned first weighting coefficient; calculating a second discharge level by using the effective balancing counts according to an assigned second weighting coefficient; and the first discharge level plus the second discharge level equals the self-discharge level of the battery cell.
[0015] This application, by setting different weighting coefficients for available equalization cycles and effective equalization cycles, and calculating the corresponding discharge levels, enables a more precise quantification of the cell's self-discharge behavior. This method improves the accuracy of cell state assessment and provides more reliable data support for battery management systems.
[0016] In conjunction with the first aspect, in one possible implementation, the first weighting coefficient is less than the second weighting coefficient.
[0017] This application improves the self-discharge level of battery cells by increasing the weight of the effective equalization count. The effective equalization count reflects the cell's performance in actual operation; therefore, giving it a higher weight in the calculation can more accurately identify cells with abnormal self-discharge.
[0018] In conjunction with the first aspect, in one possible implementation, the conditions for the battery pack to enable cell balancing include: obtaining the maximum and minimum cell voltages among multiple cells; when the difference between the maximum and minimum cell voltages reaches a first preset threshold, the battery pack enables cell balancing; when the difference decreases to a second preset threshold, the battery pack stops cell balancing.
[0019] This application sets conditions for starting and stopping cell balancing in the battery pack. Specifically, balancing is started when the difference between the maximum and minimum cell voltages reaches a first preset threshold and stopped when it reaches a second preset threshold. By starting and stopping cell balancing in a timely manner, this scheme effectively reduces the voltage difference between cells and improves the overall consistency of the battery pack.
[0020] Secondly, this application also provides a self-discharge detection device. The device includes modules for performing the method in the first aspect or any optional implementation thereof. Exemplarily, the device includes:
[0021] The calculation module is used to obtain the available number of equalization cycles for a battery cell, as well as the effective number of equalization cycles for a battery cell.
[0022] The data conversion module calculates the self-discharge level of the battery cell based on the available equalization times and the effective equalization times.
[0023] The judgment module is used to determine whether the battery cell is a self-discharge abnormality battery cell.
[0024] Thirdly, this application also provides a self-discharge detection device, including a memory and a processor, wherein the memory is used to store computer programs or instructions; when the computer programs or instructions are executed by the processor, the self-discharge detection method in the first aspect or any optional implementation of the first aspect is implemented.
[0025] Fourthly, this application also provides a self-discharge detection system, including the self-discharge detection device and battery pack described in the third aspect.
[0026] Fifthly, this application also provides a non-volatile computer storage medium storing computer program instructions, such that when the computer program instructions are invoked by a processor, the self-discharge detection method in the first aspect or any optional implementation of the first aspect is executed.
[0027] The beneficial effects of aspects two through five above can be referenced to aspect one or any possible implementation thereof, and will not be elaborated upon here. Based on the implementations provided in the above aspects, this application can also be further combined to provide more implementations.
[0028] Other advantages, objectives and features of this application will be partly apparent from the description below, and partly understood by those skilled in the art through study and practice of this application. Attached Figure Description
[0029] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.
[0030] Figure 1 This is one of the flowcharts illustrating a self-discharge detection method in an exemplary embodiment of this application;
[0031] Figure 2 This is a second flowchart illustrating a self-discharge detection method in an exemplary embodiment of this application;
[0032] Figure 3 This is a flowchart of the sub-steps of step S104;
[0033] Figure 4 This is a schematic diagram of a self-discharge detection device;
[0034] Figure 5 This is one of the schematic diagrams of a self-discharge detection system shown in an exemplary embodiment of this application;
[0035] Figure 6 This is a second schematic diagram of a self-discharge detection system shown in an exemplary embodiment of this application. Detailed Implementation
[0036] It should be noted that, in this application, the terms "exemplary" or "for example" are used to indicate that something is being described as an example, illustration, or illustration. Any embodiment or design described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or design solutions. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.
[0037] The term "and / or" as used in this application includes any and all combinations of one or more of the associated listed items. In this application, "at least one" means one or more, and "more than one" means two or more. The terms "first," "second," and other ordinal terms used in this application may be used to describe various constituent elements, but these constituent elements are not limited by these terms. The purpose of using these terms is solely to distinguish one constituent element from others and should not be construed as indicating or implying relative importance. For example, without departing from the scope of this application, a first constituent element may be named a second constituent element, and similarly, a second constituent element may be named a first constituent element.
[0038] Before introducing the embodiments of this application, the technical terms and background technology involved in this application will be introduced first.
[0039] Self-discharge: refers to the phenomenon where a battery cell undergoes a chemical reaction within itself when it is not connected to an external load or is not being charged or discharged, resulting in a gradual decrease in the battery cell's charge and voltage.
[0040] Battery cell: refers to a single electrochemical energy storage unit in a battery pack, and is the most basic energy storage unit in a battery system.
[0041] Battery pack: In this application, it specifically refers to a string of cells formed by connecting several individual cells in series.
[0042] In related technologies, a common method for detecting self-discharge anomalies in battery cells is to fully charge each cell in the battery pack, let it stand for a period of time, and then measure the voltage of each cell to find the one with the lowest voltage. This method has a long detection cycle and is only suitable for testing before the battery pack leaves the factory; it is not suitable for testing during battery pack operation, such as during the operation of an electric vehicle's battery pack. To solve the above problems, this application provides a self-discharge detection method that can perform self-discharge detection during battery pack operation without waiting for a standby period. It enables real-time detection of cell self-discharge anomalies during operation, allowing for early detection of cell self-discharge problems and ensuring the safety and reliability of the battery system.
[0043] The following first describes one or more exemplary operating environments to facilitate a clearer understanding of the functions and intentions of the various implementation methods in the embodiments of this application. For example... Figure 5 The self-discharge detection system shown can serve as an implementation environment for the self-discharge detection method provided in this application embodiment. This implementation environment includes a controller and a battery pack. The controller is connected to the battery pack and is used to process the cell data of the battery pack. The method of this application can be executed by the controller. Alternatively, as... Figure 6The self-discharge detection system shown can also serve as the implementation environment for the self-discharge detection method provided in this application embodiment. The implementation environment includes: a controller, a cloud platform, and a battery pack. The battery pack is connected to the controller. The cloud platform is connected to the controller and is used to receive and store the cell data uploaded by the controller. Based on the cell data, the method of this embodiment is executed. That is, the cloud platform can serve as the execution subject of the method embodiment applied for, thereby solving the problems of insufficient local storage capacity and insufficient computing power of the controller.
[0044] Several embodiments of this application are described below with reference to the accompanying drawings. It should be understood that the following embodiments can be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein.
[0045] refer to Figure 1 In a first aspect, this application provides a self-discharge detection method, the execution entity of which can be a self-discharge detection system. The method of this application includes:
[0046] S102: During each equalization of the battery pack, for each cell in the battery pack, obtain the available number of equalizations for the cell and the effective number of equalizations for the cell.
[0047] S104: Calculate the self-discharge level of the battery cell based on the number of available equalization cycles and the number of effective equalization cycles.
[0048] S106: When the self-discharge level of the battery cell meets the preset self-discharge conditions, the battery cell is determined to be a self-discharge abnormal battery cell.
[0049] This application enables real-time acquisition of the available and effective equalization times of each cell during battery pack equalization, thereby achieving real-time monitoring of cell self-discharge levels. By utilizing existing data from the cell equalization process, it eliminates the need for additional complex measurement equipment and prolonged static observation, simplifying the detection process and improving detection efficiency. Furthermore, this method can detect self-discharging cells in real-time via software during cell operation, facilitating user replacement, reducing the cost and cycle time for detecting cell self-discharge, and is compatible with different types of batteries.
[0050] The following combination Figures 1-3 The steps in steps S102 to S106, as well as other optional steps, are described in detail.
[0051] Regarding S102 During each equalization of the battery pack, for each cell in the battery pack, obtain the number of available equalization times for the cell and the number of effective equalization times for the cell.
[0052] There are no restrictions on the specific battery pack balancing scheme; it can be either active or passive. Here, we will use passive balancing as an example. Battery pack balancing refers to the process where, during battery pack operation, the battery pack undergoes charging and discharging. During charging and discharging, the voltage of each cell within the battery pack will differ. When the difference between the voltage of the largest and smallest cells in the battery pack reaches a first preset threshold, cell balancing will be initiated.
[0053] For example, when the first preset threshold is set to 200mV, when the difference between the maximum cell voltage and the minimum cell voltage reaches 200mV, the maximum cell voltage in the battery pack initiates cell balancing, and the voltage of the maximum cell begins to decrease until the difference between the maximum cell voltage and the minimum cell voltage reaches the second preset threshold. For example, when the second preset threshold is set to 20mV, the battery pack stops balancing when the difference between the maximum cell voltage and the minimum cell voltage reaches 20mV.
[0054] It is understandable that the first and second preset thresholds are set specifically according to the characteristics of the individual battery cells. This application defines the specific conditions under which the battery pack enters cell balancing, and clarifies the criteria for initiating cell balancing through the first and second preset thresholds, avoiding misjudgments of the balancing state and further ensuring the accuracy and stability of the subsequent self-discharge detection method.
[0055] Available balancing counts and effective balancing counts are two different indicators used to monitor the participation of battery cells in the balancing process. Available balancing counts refer to the number of times a battery cell is set as the target battery cell when it has not started balancing during each balancing process. Effective balancing counts refer to the number of times a battery cell is set as the target battery cell when only one battery cell has not started balancing during each balancing process.
[0056] Therefore, refer to Figure 2 In some implementations, the methods for obtaining the available number of equalization cycles and the effective number of equalization cycles for a battery cell include:
[0057] S202: Increase the available balancing count of the cell that has not started balancing in this balancing process by one; increase the effective balancing count of the cell that is the only one that has not started balancing in this balancing process by one.
[0058] For example, when the battery pack initiates a balancing process, the cells that are not yet balanced are recorded as target cells. The available balancing counts for the target cells are increased by one from the initial value, while the available balancing counts for the remaining cells remain at the initial value. The available balancing counts for the cells after this balancing process are recorded as the initial value for the available balancing counts for the next balancing process. After each balancing process, the self-discharge level of each cell is calculated based on its available balancing counts and effective balancing counts. This determines whether the cell's self-discharge level meets the discharge conditions. If it does, the cell is identified as having abnormal self-discharge; otherwise, it is identified as having normal self-discharge.
[0059] In one possible implementation, the example is described with two cell balancing attempts. As shown in Table 1, multiple cells are labeled as No. 1, No. 2, No. 3...N, and the available balancing attempts are denoted as Cnt. Before the battery pack is running, the initial value of the available balancing attempts for all cells is 0. When the battery pack starts cell balancing for the first time, if the target cells for this non-balanced cell balancing are No. 1 and No. 2, the available balancing attempts for No. 1 are recorded as Cnt(1) = 1, and the available balancing attempts for No. 2 are recorded as Cnt(2) = 1. The number of times the cell can be balanced is the initial value. When the battery pack starts cell balancing for the second time, if the target cells that are not balanced this time are cell 1 and cell 3, record the number of times cell 1 can be balanced Cnt(1) = 2 and the number of times cell 3 can be balanced Cnt(3) = 1. The number of times the remaining cells can be balanced is consistent with the number of times the cells can be balanced after the last balancing. Repeat this process and record the number of times the cells can be balanced each time. After each cell balancing is completed, calculate the degree of self-discharge of the cells and determine whether the cells are abnormal cells with self-discharge.
[0060] Table 1
[0061]
[0062] This application dynamically tracks the number of times each cell can be balanced by recording and counting the cells that are not balanced during each balancing process. This continuously updated mechanism reflects the specific state changes of the cells during use, providing a more comprehensive understanding of the cell's health status.
[0063] To calculate the self-discharge level of the battery cell, it is also necessary to obtain the effective equalization count of the battery cell.
[0064] For example, when the battery pack initiates a balancing process, if only one cell is not balancing while the rest are, this single cell is recorded as the target cell. The effective balancing count for the target cell is incremented by one from the initial value, while the effective balancing counts for the remaining cells remain at the initial value. The effective balancing count after this cell balancing process ends is recorded as the initial value for the effective balancing count after the next cell balancing process begins. After each cell balancing process, the self-discharge level of each cell is calculated based on the available balancing counts and the effective balancing counts. This determines whether the cell's self-discharge level meets the discharge conditions. If it does, the cell is identified as having abnormal self-discharge; otherwise, it is identified as having normal self-discharge.
[0065] In one possible implementation, as shown in Table 2, the embodiment is described with five cell balancing cycles. Multiple cells are labeled as No. 1, No. 2, No. 3...N, and the effective balancing cycle is denoted as CNT. Before the battery pack is running, the initial value of the effective balancing cycle of all cells is 0. When the battery pack starts cell balancing for the first time, if only cell No. 1 is not started this time, then cell No. 1 is the target cell, and the effective balancing cycle of cell No. 1 is recorded as CNT(1) = 1. The effective balancing cycle of the remaining cells remains at the initial value.
[0066] When the battery pack initiates cell balancing for the second time, if cell balancing is not initiated for cells 1 and 3, then the number of effective cell balancing attempts will remain the same as the number of effective cell balancing attempts after the last balancing.
[0067] When the battery pack activates cell balancing for the third time, if cell balancing is not activated this time and only cell number 2 is activated, then cell number 2 is the target cell, and the effective balancing count of cell number 2 is recorded as CNT(2) = 1. The effective balancing counts of the other cells are consistent with the effective balancing counts of the cells after the last balancing.
[0068] When the battery pack activates cell balancing for the fourth time, if cell balancing is not activated this time and only cell 1 is activated, then cell 1 is the target cell, and the effective balancing count of cell 1 is recorded as CNT(1) = 2. The effective balancing counts of the other cells are consistent with the effective balancing counts of the cells after the last balancing.
[0069] When the battery pack initiates cell balancing for the fifth time, if only cell number 1 is not balancing this time, then cell number 1 is the target cell, and the effective balancing count for cell number 1 is recorded as CNT(1) = 3. The effective balancing counts for the other cells remain the same as those after the last balancing. This process is repeated, recording the effective balancing count for each cell. After each balancing cycle, the self-discharge level of the cell is calculated to determine whether the cell is an abnormal self-discharge cell.
[0070] Table 2
[0071]
[0072] It is understandable that when cell balancing is activated, the number of available balancing cycles and the number of effective balancing cycles are recorded together, as shown in Table 3. In one possible implementation, taking the battery pack balancing five times in the above embodiment as an example, when cell balancing is activated for the first time, cell 1 is not balancing. Therefore, the number of available balancing cycles Cnt(1) of cell 1 is 1, and the number of effective balancing cycles CNT(1) of cell 1 is 1. The number of available balancing cycles and the number of effective balancing cycles of the remaining cells remain at their initial values.
[0073] When cell balancing is initiated for the second time, cells 1 and 3 are not balancing. Therefore, the number of balancing attempts available for cell 1 is Cnt(1) = 2; the number of balancing attempts available for cell 3 is Cnt(3) = 1; the number of balancing attempts available for the remaining cells is consistent with the number of balancing attempts available for the cells after the last balancing; the number of effective balancing attempts for all cells is consistent with the number of effective balancing attempts for the cells after the last balancing.
[0074] When cell balancing is activated for the third time, only cell 2 is not activated. Therefore, the number of times cell balancing can be performed Cnt(2) = 1 and the number of times cell balancing can be performed CNT(2) = 1. The number of times the remaining cells can be balanced and the number of times the cells can be performed remain the same as the number of times the cells can be balanced and the number of times the cells can be performed after the last balancing.
[0075] When cell balancing is activated for the fourth time, only cell 1 is not activated. Therefore, the number of times cell balancing can be performed Cnt(1) = 3 and the number of times cell balancing can be performed CNT(1) = 2. The number of times the remaining cells can be balanced and the number of times the cells can be performed remain the same as the number of times the cells can be balanced and the number of times the cells can be performed after the last balancing.
[0076] When cell balancing is activated for the fifth time, only cell 1 is not activated. Therefore, the number of times cell balancing can be performed Cnt(1) = 4 and the number of times cell balancing can be performed CNT(1) = 3. The number of times the remaining cells can be balanced and the number of times the cells can be performed remain the same as the number of times the cells can be balanced and the number of times the cells can be performed after the last balancing.
[0077] Table 3
[0078]
[0079] This application enables comprehensive monitoring of a battery cell's performance during the equalization process by simultaneously recording both the available and effective equalization counts. After each equalization, the self-discharge level of the cell is calculated based on the available and effective equalization counts, allowing for timely identification of cells with abnormal self-discharge and enhancing the system's ability to identify and diagnose abnormal cells at an early stage.
[0080] refer to Figure 3 After obtaining the available balancing count and the effective balancing count of the battery cell, S104 calculates the self-discharge level of the battery cell based on the available balancing count and the effective balancing count, including:
[0081] S302: Calculate the first discharge level by using the available equalization times according to the assigned first weighting coefficient; calculate the second discharge level by using the effective equalization times according to the assigned second weighting coefficient.
[0082] S304: The first discharge level plus the second discharge level equals the self-discharge level of the battery cell.
[0083] For example, the first weighting coefficient is set to k, the second weighting coefficient is m, and the formula for calculating the degree of self-discharge is: T(N)=k*Cnt(N)+m*CNT(N).
[0084] Where N is the cell number, k*Cnt(N) is the first discharge level of cell number N; m*CNT(N) is the second discharge level of cell number N; and T(N) is the self-discharge level of cell number N.
[0085] In one possible implementation, k is set to 0.01 and m to 0.1. The self-discharge condition is set to a self-discharge level T(N) greater than 2, which determines the cell as having abnormal self-discharge. For example, when Cnt(1) = 4 and CNT(1) = 3, the self-discharge level of cell 1 is calculated as T(1) = 0.01*4 + 0.1*3 = 0.34. Since 0.34 < 2, cell 1 is judged to be a cell with normal self-discharge. For example, when Cnt(2) = 21 and CNT(2) = 18, the self-discharge level of cell 2 is calculated as T(2) = 0.01*21 + 0.1*18 = 2.01. Since 2.01 > 2, cell 2 is judged to be a cell with abnormal self-discharge.
[0086] It is understood that the values of the first weighting coefficient, the second weighting coefficient, and the self-discharge condition are set according to the cell model and data, and this application does not limit them.
[0087] By setting different weighting coefficients for available equalization attempts and effective equalization attempts, and calculating the corresponding discharge levels, the self-discharge behavior of the battery cell can be quantified more accurately. This method improves the accuracy of cell state assessment and provides more reliable data support for battery management systems.
[0088] In one possible implementation, the first weighting coefficient is less than the second weighting coefficient. This is because the number of available balancing cycles reflects the overall situation of a cell not being balanced in multiple balancing cycles, and can be used to reflect the balancing demand trend of the cell, but cannot be used as a reliable basis for judging abnormal self-discharge of the cell.
[0089] The effective equalization count reflects the frequency at which a particular cell does not require equalization when all other cells have been equalized. A high effective equalization count may indicate a lower voltage, meaning the cell does not need to participate in equalization. In other words, this cell exhibits worse self-discharge performance than other cells, directly reflecting its self-discharge performance and thus carrying higher weight and reliability in determining whether a cell is exhibiting abnormal behavior. Therefore, assigning a higher weight to the effective equalization count in the calculation can more accurately identify cells with abnormal self-discharge.
[0090] In one possible implementation, the self-discharge level of the battery cell is positively correlated with both the available balancing count and the effective balancing count. Since a higher number of available and effective balancing counts indicates a higher frequency at which the battery cell does not need balancing, the cell's voltage is lower, making it easier to identify as a cell with abnormal self-discharge.
[0091] Thus, by establishing a positive correlation between the degree of self-discharge and the number of available balancing cycles and the number of effective balancing cycles, the higher the number of available balancing cycles and the number of effective balancing cycles, the greater the degree of self-discharge. The greater the degree of self-discharge, the more severe the self-discharge of the cell. This allows for a more accurate identification of the cell's self-discharge trend.
[0092] Secondly, based on the same technical concept, and referring to... Figure 4 This application also provides a self-discharge detection device, including a calculation module, a data conversion module, and a judgment module.
[0093] The calculation module is used to obtain the available number of equalization cycles and the effective number of equalization cycles of the battery cell; the data conversion module calculates the self-discharge level of the battery cell based on the available number of equalization cycles and the effective number of equalization cycles; the judgment module is used to determine whether the battery cell is a self-discharge abnormal cell.
[0094] For more details, please refer to the method implementation examples in the first aspect, which will not be repeated here.
[0095] It should be noted that the various modules described herein are divided into modules for clarity. However, in actual implementation, the boundaries between modules may be blurred. For example, any or all functional modules in this application may share various hardware and / or software elements. As another example, any and / or all functional modules in this application may be wholly or partially implemented by a shared processor executing software instructions. Furthermore, various software sub-modules executed by one or more processors may be shared among various software modules. Accordingly, unless expressly required, the scope of this application is not limited by mandatory boundaries between various hardware and / or software elements.
[0096] Thirdly, based on the same technical concept, this application also provides a self-discharge detection device, including a memory and a processor. The memory stores computer programs or instructions; when the computer program or instructions are executed by the processor, the self-discharge detection method in the first aspect or any optional implementation of the first aspect is implemented. The physical form of the device may be... Figure 5 The controller shown, or Figure 6 The cloud platform shown.
[0097] The memory includes at least one type of computer-readable storage medium, including flash memory, hard disk, multimedia card, random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), magnetic disk, optical disk, etc. In some embodiments, the computer-readable storage medium may be an internal storage unit of an electronic device, such as the hard disk or memory of the electronic device. In other embodiments, the computer-readable storage medium may also be an external storage device of the electronic device, such as a plug-in hard disk, secure digital card (SD card), flash memory card, etc., equipped on the electronic device. Of course, the computer-readable storage medium may include both internal storage units and external storage devices of the electronic device. In this embodiment, the computer-readable storage medium is typically used to store the operating system and various application software installed on the electronic device, such as the program code of the data processing method in the embodiment. In addition, the computer-readable storage medium may also be used to temporarily store various types of data that have been output or will be output.
[0098] In some embodiments, the processor may be a central processing unit (CPU), a controller, a microcontroller, a microprocessor, or other chip. The processor is typically used to control the overall operation of the processing device, such as performing control and processing related to data interaction or communication with other entities. In this embodiment, the processor is used to run program code stored in memory or process data.
[0099] refer to Figure 5 and Figure 6 Fourthly, based on the same technical concept, this application also provides a self-discharge detection system, including the self-discharge detection device in the third aspect and a battery pack. The self-discharge detection device is connected to the battery pack and is used to collect the available balancing times and effective balancing times of the battery cells, calculate the degree of self-discharge based on the available balancing times and effective balancing times of the battery cells, determine whether the degree of self-discharge meets the preset self-discharge conditions, and determine whether the battery cell is a self-discharge abnormal battery cell.
[0100] Fifthly, based on the same technical concept, this application also provides a non-volatile computer storage medium storing computer program instructions, so that when the computer program instructions are invoked by a processor, the self-discharge detection method in the first aspect or any optional implementation of the first aspect is executed. Further details can be found in the method embodiments, which will not be repeated here. In this embodiment, the computer-readable storage medium can be non-volatile or volatile. Computer-readable storage media include flash memory, hard disk, multimedia card, random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), magnetic disk, optical disk, etc. In some embodiments, the computer-readable storage medium can be an internal storage unit of an electronic device, such as the hard disk or memory of the electronic device. In other embodiments, the computer-readable storage medium can also be an external storage device of the electronic device, such as a plug-in hard disk, a secure digital card (SD) card, a flash memory card, etc., equipped on the electronic device. Of course, the computer-readable storage medium can also include both internal storage units and external storage devices of the electronic device. In this embodiment, the computer-readable storage medium is typically used to store the operating system and various application software installed on the electronic device, such as the program code of the data processing method in the embodiment. In addition, computer-readable storage media can also be used to temporarily store various types of data that have been output or will be output.
[0101] It should be noted that the order in which the embodiments are described in this application is not intended to limit the priority of the embodiments. The reference to "embodiment" herein means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.
[0102] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this application and in its specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.
[0103] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many forms under the guidance of this application without departing from the spirit and scope of protection of the claims. All equivalent transformations made under the inventive concept of this application using the content of this application's specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this application.
Claims
1. A self-discharge detection method, characterized in that, include: During each equalization of the battery pack, for each cell in the battery pack, the available number of equalizations for that cell and the effective number of equalizations for that cell are obtained. The self-discharge level of the battery cell is calculated based on the number of available equalization cycles and the number of effective equalization cycles. When the self-discharge level of the battery cell meets the preset self-discharge conditions, the battery cell is determined to be a self-discharge abnormal battery cell. The step of obtaining the number of available equalization cycles for the battery cell includes: Increase the available balancing attempts for cells that were not balancing in this balancing process by one. The number of effective balancing operations for the battery cell includes: The effective balancing count of the only cell that was not balancing in this balancing process is increased by one; the self-discharge level of the cell is positively correlated with the available balancing count and the effective balancing count, respectively. The calculation of the self-discharge level of the battery cell based on the available equalization cycles and the effective equalization cycles includes: The first discharge level is obtained by calculating the available equalization times according to the assigned first weighting coefficient; The second discharge level is obtained by calculating the number of effective equalizations according to the assigned second weighting coefficient; The first discharge level plus the second discharge level equals the self-discharge level of the battery cell.
2. The self-discharge detection method according to claim 1, characterized in that, The first weighting coefficient is less than the second weighting coefficient.
3. The self-discharge detection method according to any one of claims 1 to 2, characterized in that, The battery pack meets the conditions for activating cell balancing by: acquiring the maximum and minimum cell voltages among the multiple cells; when the difference between the maximum and minimum cell voltages reaches a first preset threshold, the battery pack activates cell balancing; when the difference decreases to a second preset threshold, the battery pack stops cell balancing.
4. A self-discharge detection device, characterized in that, include: The calculation module is used to obtain the available number of equalization cycles for a battery cell, as well as the effective number of equalization cycles for a battery cell. The data conversion module calculates the self-discharge level of the battery cell based on the available equalization times and the effective equalization times. The judgment module is used to determine whether the battery cell is a self-discharge abnormality battery cell; The step of obtaining the number of available equalization cycles for the battery cell includes: Increase the available balancing attempts for cells that were not balancing in this balancing process by one. The number of effective balancing operations for the battery cell includes: The effective balancing count of the only cell that was not balancing in this balancing process is increased by one; the self-discharge level of the cell is positively correlated with the available balancing count and the effective balancing count, respectively. The calculation of the self-discharge level of the battery cell based on the available equalization cycles and the effective equalization cycles includes: The first discharge level is obtained by calculating the available equalization times according to the assigned first weighting coefficient; The second discharge level is obtained by calculating the number of effective equalizations according to the assigned second weighting coefficient; The first discharge level plus the second discharge level equals the self-discharge level of the battery cell.
5. A self-discharge detection device, characterized in that, It includes a memory and a processor, wherein the memory is used to store computer programs or instructions; when the computer programs or instructions are executed by the processor, the self-discharge detection method according to any one of claims 1-3 is implemented.
6. A self-discharge detection system, characterized in that, It includes the self-discharge detection device and battery pack as described in claim 5.
7. A non-volatile computer storage medium, characterized in that, The non-volatile computer storage medium stores computer program instructions so that when the computer program instructions are invoked by a processor, the self-discharge detection method as described in any one of claims 1-3 is executed.