Method, device and equipment for estimating health status of battery stack cells

Abstract

The present invention relates to the technical field of energy storage batteries, and provides a method, device and equipment for estimating the health status of a battery stack, the method comprising: obtaining relevant parameters of the battery stack; performing consistency detection on the battery stack according to the relevant parameters, and determining whether the battery stack meets the strategy switching start-up conditions based on the consistency detection results; determining whether the battery stack meets the target judgment conditions when it is determined that the battery stack meets the strategy switching start-up conditions; the target judgment conditions are used to characterize the conditions that the battery stack meets the health status of the battery stack calculated by ampere-hour integration; when it is determined that the battery stack meets the target judgment conditions, determining the health status of the real battery stack battery by the ampere-hour integration method; when it is determined that the battery stack does not meet the target judgment conditions, determining the health status of the real battery stack battery by the parameter identification method. The present invention improves the accuracy of battery stack health estimation.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage batteries, and in particular to a method, device and equipment for estimating the health status of batteries in a battery stack. Background Art

[0002] As the cost of energy storage batteries decreases, the advantages of battery energy storage (electrochemical energy storage) technology over pumped storage, compressed air, supercapacitors and other energy storage methods are becoming more and more obvious. In recent years, the application scale of battery energy storage has seen explosive growth. At present, energy storage systems can be mainly divided into large-scale energy storage, industrial and commercial energy storage, and household storage according to the use area. Large-scale energy storage stations are an important technical means to promote the application of green and renewable energy. They play an important role in peak shaving and valley filling, and large-scale energy storage plays an important role in grid stability. Industrial and commercial energy storage and household storage are more targeted at enterprises and users. They not only use the fluctuations in grid electricity prices to produce certain economic effects, but also reduce daily electricity consumption to a certain extent.

[0003] In a battery management system, accurately calculating the battery health status of the battery is crucial to understanding the battery status and extending the battery life. Traditional battery cluster battery health status calculation methods mainly include offline fitting method or cumulative cycle method, but the key point of these methods is that the initial value of the battery health status (State of Health, SOH) is set to 100% by default. When the above conditions are not met, there will be errors throughout the process. Furthermore, in large-scale energy storage systems, the battery stack management unit collects the information of the entire energy storage battery compartment, and the health status SOH value displayed represents the health status of the entire battery stack. In the prior art, the battery cluster’s lowest battery health status value is taken by default according to the short board effect to represent the health status of the battery stack battery, resulting in low accuracy in the health status estimation of the battery stack battery. Summary of the invention

[0004] The present invention provides a method, device and equipment for estimating the health status of batteries in a battery stack, so as to solve the defect of low accuracy in estimating the health status of batteries in the prior art and improve the accuracy of estimating the health status of batteries in the battery stack.

[0005] In a first aspect, the present invention provides a method for estimating the health status of a battery stack, the method comprising the following steps:

[0006] Obtain relevant parameters of the battery stack;

[0007] Performing consistency detection on the battery stack according to the relevant parameters, and determining whether the battery stack meets the strategy switching start condition based on the consistency detection result; the strategy switching start condition is used to characterize the condition that the consistency deviation of the battery stack exceeds a preset range;

[0008] In the case where it is determined that the battery stack satisfies the strategy switching start condition, determining whether the battery stack satisfies a target judgment condition; the target judgment condition is used to indicate that the battery stack satisfies a condition for calculating a battery health status of the battery stack through ampere-hour integration;

[0009] When it is determined that the battery stack meets the target judgment condition, determining the health status of the real battery stack battery by using the ampere-hour integration method;

[0010] When it is determined that the battery stack does not meet the target judgment condition, the health status of the actual battery stack cells is determined by a parameter identification method.

[0011] According to a method for estimating the health status of a battery stack provided by the present invention, the relevant parameters include a maximum voltage value of a single cell and a minimum voltage value of a single cell; the consistency detection of the battery stack is performed according to the relevant parameters, and based on the consistency detection result, it is determined whether the battery stack meets the strategy switching start condition, including:

[0012] Determining a voltage deviation in a charge-discharge cycle according to the maximum voltage value of the single cell and the minimum voltage value of the single cell;

[0013] Based on the voltage deviation and a preset voltage deviation threshold, determining the consistency detection result; the consistency detection result includes: the voltage consistency deviation is too large or the voltage consistency deviation is normal;

[0014] When the consistency detection result is that the voltage consistency deviation is too large, it is determined that the battery stack meets the strategy switching start condition.

[0015] According to a method for estimating the health status of a battery stack provided by the present invention, the relevant parameters also include the operating status of the battery stack and the percentage value of the remaining capacity of each battery cluster under the battery stack; the consistency detection of the battery stack according to the relevant parameters, and determining whether the battery stack meets the policy switching start condition based on the consistency detection result, includes:

[0016] When the operating state of the battery stack changes from a static state to a charge and discharge stage, determining a percentage value of a remaining capacity of each battery cluster under the battery stack;

[0017] Determining the deviation of the remaining capacity percentage value of each battery cluster according to the remaining capacity percentage value of each battery cluster under the battery stack;

[0018] Based on the residual capacity percentage value deviation of each battery cluster and a preset residual capacity percentage value deviation threshold, the consistency detection result is determined; the consistency detection result includes: the residual capacity percentage value deviation consistency deviation of each battery cluster is too large or the residual capacity percentage value deviation consistency deviation of each battery cluster is normal;

[0019] When the consistency detection result is that the consistency deviation of the remaining capacity percentage values ​​of each battery cluster is too large, it is determined that the battery stack meets the strategy switching start condition.

[0020] According to a method for estimating the health status of a battery stack provided by the present invention, the relevant parameters also include a maximum temperature of a single cell and a minimum temperature of a single cell; and determining whether the battery stack meets a target judgment condition includes:

[0021] Determine whether the battery stack meets the first-level judgment condition based on the relevant parameters; the first-level judgment condition includes: the maximum temperature of the single cell and the minimum temperature of the single cell in the whole charging and discharging stage are both within the effective temperature range; the maximum temperature of the single cell is determined based on the maximum temperature of the battery stack, and the minimum temperature of the single cell is determined based on the minimum temperature of the battery stack; and the absolute value of the difference between the initial remaining capacity percentage value and the ending remaining capacity percentage value in the charging or discharging stage of the battery stack and the cumulative capacity are both greater than the validity calculation deviation value;

[0022] When it is determined that the battery stack satisfies the primary judgment condition, and when it is determined that the battery stack satisfies at least one secondary judgment condition, it is determined that the battery stack satisfies the target judgment condition.

[0023] According to a method for estimating the health status of a battery stack provided by the present invention, the health status of a real battery stack battery is determined by the ampere-hour integration method, comprising:

[0024] Determine the initial remaining capacity percentage value that satisfies the strategy switching start condition, the ending remaining capacity percentage value that satisfies the strategy switching start condition, and the accumulated ampere-hour Ah value that satisfies the effective temperature range during the charging and discharging process;

[0025] Determining an absolute value of a ratio difference based on the initial remaining capacity percentage value and the ending remaining capacity percentage value;

[0026] Dividing the absolute value of the ratio difference by the accumulated ampere-hour Ah value to determine the capacity value of the battery stack calculated by the current ampere-hour integration method;

[0027] The health status of the real battery stack battery is determined based on the capacity value of the battery stack, the rated value of the battery stack capacity value, the health status of the real battery stack battery calculated by the short board effect of the current scheduling cycle, and the health status of the real battery stack battery output in the previous scheduling cycle.

[0028] According to a method for estimating the health status of a battery stack provided by the present invention, the determining of the initial remaining capacity percentage value that satisfies the strategy switching start condition includes:

[0029] When in a charging state, when the lowest voltage value of the single cell meets the judgment threshold and the standing time meets the OCV voltage sampling standing time, the remaining capacity percentage value corresponding to the cell voltage is determined as the initial remaining capacity percentage value;

[0030] When in a charging state, when the lowest voltage value of the single cell reaches the full discharge cut-off voltage condition in the previous discharge cycle, 0% is determined as the initial remaining capacity percentage value;

[0031] When in a discharging state, when the highest voltage value of the single cell meets the judgment threshold and the standing time meets the OCV voltage sampling standing time, the remaining capacity percentage value corresponding to the highest cell is determined as the initial remaining capacity percentage value;

[0032] When in a discharging state, when the highest voltage value of the single cell reaches the full charge cut-off voltage condition in the previous charging cycle, 100% is determined as the initial remaining capacity percentage value.

[0033] According to a method for estimating the health status of a battery stack provided by the present invention, the determining of the ending remaining capacity percentage value that satisfies the strategy switching start condition includes:

[0034] When the charging is finished, when the highest voltage value of the single cell meets the judgment threshold and the standing time meets the OCV voltage sampling standing time, the remaining capacity percentage value corresponding to the highest cell is used as the termination condition for judging the remaining capacity percentage;

[0035] When the charging is finished and the highest voltage value of the single cell reaches the full charge cut-off voltage condition, 100% is determined as the ending remaining capacity percentage value;

[0036] When the discharge is terminated, when the lowest voltage value of the single cell meets the judgment threshold and the rest time meets the OCV voltage sampling rest time, the remaining capacity percentage value corresponding to the lowest cell is determined as the ending remaining capacity percentage value;

[0037] When the discharge is terminated and the lowest cell voltage of the battery stack reaches the full discharge cut-off voltage condition, 0% is determined as the final remaining capacity percentage value.

[0038] According to a method for estimating the health status of a battery stack provided by the present invention, the related parameters also include the total current of the battery stack; the determining the health status of the actual battery stack battery by the parameter identification method includes:

[0039] Determine the rated value of the battery stack capacity value at the current temperature according to the battery stack operating state, the battery stack total current, the single cell voltage value and the single cell temperature;

[0040] The health status of the actual battery stack battery is determined based on the current remaining capacity percentage value of the battery stack at the current temperature and the rated value of the battery stack capacity value at the current temperature.

[0041] In a second aspect, the present invention further provides a device for estimating the health status of a battery stack, the device comprising the following modules:

[0042] An acquisition module is used to obtain relevant parameters of the battery stack;

[0043] A strategy switching module, used to perform consistency detection on the battery stack according to the relevant parameters, and determine whether the battery stack meets the strategy switching start condition based on the consistency detection result; the strategy switching start condition is used to indicate the condition that the consistency deviation of the battery stack exceeds a preset range;

[0044] In the case where it is determined that the battery stack satisfies the strategy switching start condition, determining whether the battery stack satisfies a target judgment condition; the target judgment condition is used to indicate that the battery stack satisfies a condition for calculating a battery health status of the battery stack through ampere-hour integration;

[0045] An evaluation module, configured to determine the health status of the actual battery stack battery by an ampere-hour integration method when it is determined that the battery stack meets the target judgment condition;

[0046] When it is determined that the battery stack does not meet the target judgment condition, the health status of the actual battery stack cells is determined by a parameter identification method.

[0047] In a third aspect, the present invention further provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, a method for estimating the health status of a battery stack as described above is implemented.

[0048] In a fourth aspect, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements a method for estimating the health status of a battery stack battery as described in any one of the above.

[0049] In a fifth aspect, the present invention further provides a computer program product, comprising a computer program, which, when executed by a processor, implements any of the above-described methods for estimating the health status of a battery stack.

[0050] The method, device and equipment for estimating the health status of a battery stack provided by the present invention obtain relevant parameters of the battery stack, wherein the relevant parameters include the operating status of the battery stack, the total current of the battery stack, the maximum voltage value of a single cell, the minimum voltage value of a single cell, the health status value of each battery cluster, the percentage value of the remaining capacity of each battery cluster under the battery stack, the maximum temperature of the battery stack and the minimum temperature of the battery stack; then, the battery stack is subjected to consistency detection according to the relevant parameters, and based on the consistency detection result, it is determined whether the battery stack meets the strategy switching start-up condition, and the strategy switching start-up condition is used to characterize the condition that the consistency deviation of the battery stack exceeds a preset range; when it is determined that the battery stack meets the strategy switching start-up condition, it is determined whether the battery stack meets the target judgment condition, and the target judgment condition is used to characterize the condition that the battery stack meets the condition that the health status of the battery stack is calculated by ampere-hour integration; further, when it is determined that the battery stack meets the target judgment condition, the health status of the real battery stack battery is determined by the ampere-hour integration method; when it is determined that the battery stack does not meet the target judgment condition, the health status of the real battery stack battery is determined by the parameter identification method.

[0051] In the present invention, relevant parameters of the battery stack are first obtained, and it is clarified that the ampere-hour integration method is used when the strategy switching start-up conditions and the target judgment conditions are met. The target judgment conditions are used to characterize that the battery stack meets the conditions for calculating the battery health status of the battery stack through ampere-hour integration, so as to avoid excessive calculations of the ampere-hour integration method under normal conditions, which may lead to multiple abnormal changes in the BAU-level battery health status value. At the same time, the real battery health status of the battery stack is estimated based on the highest voltage and the lowest voltage of the single cell in the entire battery stack, so as to ensure that the real battery health status value of the battery stack can be estimated when there is a consistency deviation in the battery. The present invention is suitable for calculating the battery health status of the battery stack under actual complex working conditions, which improves the accuracy of the battery health status estimation of the battery stack. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0053] Figure 1 It is one of the flow charts of the health status estimation method of the battery stack battery provided by the present invention.

[0054] Figure 2 This is the second flow chart of the method for estimating the health status of a battery stack provided by the present invention.

[0055] Figure 3This is the third flow chart of the method for estimating the health status of batteries in a battery stack provided by the present invention.

[0056] Figure 4 This is the fourth flow chart of the method for estimating the health status of batteries in a battery stack provided by the present invention.

[0057] Figure 5 It is a structural schematic diagram of the health status estimation device of the battery stack battery provided by the present invention.

[0058] Figure 6 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0059] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0060] Combine the following Figure 1-Figure 6 The method, device and apparatus for estimating the health status of a battery stack cell of the present invention are described.

[0061] Figure 1 FIG. 1 is a flow chart of a method for estimating the health status of a battery stack provided by the present invention. Figure 1 As shown, the method includes the following:

[0062] Step 101, obtaining relevant parameters of the battery stack;

[0063] Specifically, it should be noted that the executor of the present invention is a battery management system (BMS), more specifically, a battery array management unit (BAU), which is used to estimate the health status of battery stack cells and improve the accuracy of the estimation.

[0064] Among them, the battery array management unit BAU is the control core of the battery management system BMS. The main functions of BAU include: 1. Comprehensive management and coordination: BAU integrates the functions of BMU (battery management unit) and BCU (battery cluster management unit), and has more advanced functions, such as fault diagnosis and early warning, system status evaluation, etc. 2. Information aggregation and management: BAU collects information from all BCUs, is responsible for the operation status monitoring of the entire battery energy storage system and the estimation of SOC (state of charge) and SOH (state of health), and communicates with the energy storage inverter and upper-level monitoring. 3. Control command issuance: BAU issues control commands to BCU according to certain control strategies, and comprehensively manages the access and disconnection of each battery string. 4. Data interaction and communication: BAU obtains information such as voltage, current, temperature, insulation impedance, SOC, relay status, fault status, etc. of the battery system through the internal CAN bus to realize the parallel management of battery clusters. At the same time, it collects information from air conditioning, fire protection, electric meters, etc., exchanges data with EMS (energy management system) and PCS (power conversion system) through Ethernet, responds to the control strategy of EMS, and realizes energy scheduling, system thermal management and fault handling of the energy storage system. 5. System self-check and fault diagnosis: BAU is responsible for BMS system self-check and fault diagnosis alarm to ensure the safe and stable operation of the battery system. 6. Communication with other devices: BAU communicates with other devices such as PCS and EMS for data storage, transmission and processing. BAU plays a vital role in the battery management system to ensure the safe, efficient and stable operation of the entire battery system.

[0065] It should be noted that the battery stack includes multiple battery clusters, and each battery cluster is composed of a number of battery cells.

[0066] In this embodiment, the method for estimating the health status of a battery stack cell includes the following steps:

[0067] First, obtain the relevant parameters of the battery stack. Among them, the relevant parameters include the battery stack operating status, the total current of the battery stack, the maximum voltage value of the single cell, the minimum voltage value of the single cell, the battery health status value of each battery cluster, the remaining capacity percentage value of each battery cluster under the battery stack (State of Charge, SOC), the maximum temperature of the battery stack and the minimum temperature of the battery stack. The battery stack operating status is used to characterize the charging and discharging status of the battery stack, including any of the following: charging, discharging, and static. SOC refers to the state of charge of the battery, which is used to reflect the remaining capacity of the battery. The numerical value of SOC is defined as the ratio of the remaining capacity to the battery capacity, and is usually expressed as a percentage. Its value range is 0~1. When SOC=0%, it means that the battery is fully discharged, and when SOC=100%, it means that the battery is fully charged. SOC is a key parameter in the battery management system, which is usually used for battery charging management, energy management, and remaining power estimation.

[0068] In this embodiment, it is detected that the battery operating state is changing from static to charging, the current is 140A, there is a warning of excessive single cell pressure difference during the charge and discharge cycle, the lowest voltage of the single cell is 3.021V, and the corresponding remaining capacity percentage is 5% according to the corresponding offline SOC-OCV table. The real battery health state value of the battery stack at the last moment is 96%, and the minimum real battery health state value of each battery cluster is 98%. There is a large deviation in the remaining capacity percentage of each battery cluster. At the same time, the lowest temperature of the battery stack and the highest temperature of the battery stack. Among them, the battery stack operating state and temperature value are used to control the switching selection of relevant conditions and thresholds of the entire calculation method. The current, the highest / lowest voltage of the single cell, the real battery health state value of the battery stack at the last moment, and the lowest real battery health state value of each cluster will all be used as input data for subsequent steps to participate in the calculation.

[0069] Step 102: Perform consistency detection on the battery stack according to relevant parameters, and determine whether the battery stack meets the strategy switching start condition based on the consistency detection result; the strategy switching start condition is used to indicate the condition that the consistency deviation of the battery stack exceeds a preset range;

[0070] Specifically, after obtaining the relevant parameters of the battery stack, the consistency test of the battery is performed before the estimation is performed, and then the corresponding estimation strategy can be selected based on the consistency test result. The strategy switching start condition is used to characterize the condition that the consistency deviation of the battery stack exceeds the preset range.

[0071] For example, the battery consistency detection mechanism includes the detection of the maximum voltage / minimum voltage deviation of the battery stack single cell or the residual capacity percentage deviation of the battery cluster. That is, whether to switch the strategy is determined based on the deviation between the maximum voltage and the minimum voltage of the battery stack single cell and the voltage deviation threshold, or whether to switch the strategy is determined based on the deviation of the residual capacity percentage of each cluster in the battery stack and the residual capacity percentage deviation threshold, and only one determination is required.

[0072] Furthermore, if the consistency test result is inconsistent, it is determined that the battery stack meets the strategy switching start-up conditions, and the estimation strategy is further determined for calculation; if the consistency test result is consistent, the lowest battery health status value of each battery cluster is directly output according to the short-board effect of the battery health status of each battery cluster as the health status of the actual battery stack battery.

[0073] Specifically, when the difference between the highest single cell voltage and the lowest single cell voltage of the battery stack during the charge and discharge cycle meets the judgment threshold, the relevant flag is recorded, and it is judged that the battery consistency deviation is too large to enter the strategy switching stage;

[0074] Exemplarily, when the battery stack operating state changes from the static state to the charge and discharge stage, the remaining capacity percentage value of each battery cluster in the current battery stack is determined:

[0075] Considering that the energy storage battery stack system has situations such as disabled battery clusters, there is a certain deviation in the percentage of remaining capacity between battery clusters. Therefore, when entering the charge and discharge stage, the current remaining capacity percentage of each battery cluster is detected. If the maximum deviation value exceeds the judgment threshold, the corresponding flag is recorded. This flag is only used in this round.

[0076] The judgment flags of the voltage and the remaining capacity percentage are obtained respectively. When either of them is set to 1, step 103 is entered. Otherwise, if neither of them is set to 1, the lowest battery health status value of each battery cluster is selected as the current battery health status value of the battery stack for output according to the short board effect.

[0077] Step 103: when it is determined that the battery stack meets the strategy switching start condition, determine whether the battery stack meets the target judgment condition; the target judgment condition is used to indicate that the battery stack meets the condition for calculating the battery health status of the battery stack through ampere-hour integration;

[0078] Specifically, when the consistency detection result is inconsistent, that is, the battery stack meets the strategy switching start-up conditions, it is further determined whether the battery stack related parameters meet the conditions for calculating the battery health status of the battery stack through ampere-hour integration, that is, the target judgment condition.

[0079] The conditions (target judgment conditions) for calculating the health status of the battery stack through ampere-hour integration can be determined according to actual needs, and usually include multiple levels of judgment conditions, so that the judgment results are more accurate and more suitable for corresponding working conditions.

[0080] Step 104: when it is determined that the battery stack meets the target judgment condition, determine the health status of the actual battery stack battery by using the ampere-hour integration method;

[0081] Specifically, when it is determined that the battery stack meets the target judgment condition, that is, the condition that the battery stack battery health state can be calculated by ampere-hour integration is met, the health state of the actual battery stack battery is estimated by the ampere-hour integration method.

[0082] The ampere-hour integration method is a method for estimating the battery state of charge (SOC). It estimates the SOC by accumulating the amount of charge and discharge of the battery. It is also called the Ah integration method or the coulomb counting method. It is a basic method for battery power measurement. It uses the Ah accumulation method to perform real-time SOC estimation on dynamic lithium batteries. The advantage of the ampere-hour integration method is that the calculation method is simple and reliable, and it can estimate the battery state of charge in real time, and is relatively less restricted by the battery's own conditions. The disadvantage is that since the ampere-hour integration method is an open-loop detection in control, if the current acquisition accuracy is not high, the given initial state of charge has a certain error. As the system operation time extends, the errors generated previously will gradually accumulate, thereby affecting the prediction results of the state of charge.

[0083] Step 105: When it is determined that the battery stack does not meet the target judgment condition, determine the health status of the actual battery stack battery by a parameter identification method.

[0084] Furthermore, when it is determined that the battery stack does not meet the target judgment condition, that is, the condition that the battery stack battery health state can be calculated by ampere-hour integration is not met, the real battery stack battery health state is estimated by the parameter identification method. For example, the battery stack remaining capacity percentage value SOC, the battery stack real-time current and the battery stack rated capacity are used, combined with the parameter identification method to estimate the battery stack real-time capacity and complete the battery health state calculation.

[0085] The method provided in this embodiment first obtains relevant parameters of the battery stack, wherein the relevant parameters include the operating status of the battery stack, the total current of the battery stack, the maximum voltage value of the single cell, the minimum voltage value of the single cell, the battery health status value of each battery cluster, the remaining capacity percentage value of each battery cluster under the battery stack, the maximum temperature of the battery stack and the minimum temperature of the battery stack; then, the battery stack is subjected to consistency detection according to the relevant parameters, and whether the battery stack satisfies the strategy switching start-up conditions is determined based on the consistency detection result; if it is determined that the battery stack satisfies the strategy switching start-up conditions, whether the battery stack satisfies the target judgment conditions is determined, and the target judgment conditions are used to characterize that the battery stack satisfies the conditions for calculating the battery health status of the battery stack through ampere-hour integration; further, if it is determined that the battery stack satisfies the target judgment conditions, the real battery stack battery health status is determined by the ampere-hour integration method; if it is determined that the battery stack does not meet the target judgment conditions, the real battery stack battery health status is determined by the parameter identification method.

[0086] In the present invention, relevant parameters of the battery stack are first obtained, and it is clarified that the ampere-hour integration method is used when the strategy switching start-up conditions and the target judgment conditions are met. The target judgment conditions are used to characterize that the battery stack meets the conditions for calculating the battery health status of the battery stack through ampere-hour integration, so as to avoid excessive calculations of the ampere-hour integration method under normal conditions, which may lead to multiple abnormal changes in the BAU-level battery health status value. At the same time, the real battery health status of the battery stack is estimated based on the highest voltage and the lowest voltage of the single cell in the entire battery stack, so as to ensure that the real battery health status value of the battery stack can be estimated when there is a consistency deviation in the battery. The present invention is suitable for calculating the battery health status of the battery stack under actual complex working conditions, which improves the accuracy of the battery health status estimation of the battery stack.

[0087] For example, Figure 2 FIG. 2 is a flow chart of the method for estimating the health status of a battery stack provided by the present invention. Figure 2 As shown, the method includes:

[0088] Step 201 : collecting relevant parameters such as the current battery stack operating status, single cell voltage, single cell temperature, stack total current, and SOH value of each battery cluster.

[0089] Step 202: Determine whether there is a large deviation in consistency of cells in the battery stack.

[0090] If the execution result of step 202 is yes, then step 204 is executed; if the execution result of step 202 is no, then step 203 is executed.

[0091] Step 203: Take the lowest SOH value of each battery cluster and output it according to the short board effect.

[0092] Step 204: Whether the conditions for calculating the battery stack SOH by ampere-hour integration are met.

[0093] If the execution result of step 204 is yes, then step 205 is executed; if the execution result of step 204 is no, then step 206 is executed.

[0094] Step 205 : Calculate the SOH value of the battery stack according to the ampere-hour integration method.

[0095] Step 206: Calculate the battery stack SOH value according to parameter identification.

[0096] The beneficial effects of the present invention are as follows:

[0097] ① Accuracy: The present invention extracts parameters at the BAU level for lithium iron phosphate battery stacks, clarifies the use of the ampere-hour integration method when the consistency deviation of the battery cells is large, and avoids the excessive calculation of the ampere-hour integration method under normal conditions, which leads to multiple abnormal changes in the health status of the battery at the BAU level. At the same time, the true battery health status of the battery stack is estimated based on the highest / lowest voltage of the single cell in the entire battery stack, ensuring that the true battery health status value of the battery stack can be estimated when there is a consistency deviation in the battery.

[0098] ② Stability: This method takes into account that the calculation of the battery stack using the ampere-hour integration method at the BAU level may be affected by too many environmental factors. Therefore, the upper limit of the actual battery health status value is set to the minimum battery health status value of each battery cluster in the battery stack and the battery health status value calculated by the last ampere-hour integration that meets the interval time plus a fixed deviation value, and the lower limit is the battery health status value calculated by the last ampere-hour integration that meets the interval time minus the fixed deviation value; at the same time, taking into account the switching of the calculated values ​​under the two states of consistency of the battery cells in the battery stack, a relative indicator is set to display the battery health status value. This value is not allowed to have jumps, etc., to ensure the stable operation of the energy storage project.

[0099] ③ Adaptability: Because the partial derivative values ​​of the voltage plateau or OCV for the remaining capacity percentage value of different lithium iron phosphate batteries are different, the scope of application of the algorithm needs to be fully considered. The method used in the present invention selects the applicable remaining capacity percentage intervals in the range of less than 12% and more than 92%, and the standing time is about 180 minutes. If the relevant ampere-hour integration method calculation conditions are not met, the parameter identification calculation can also meet the calculation of the remaining capacity percentage value of the lithium iron phosphate battery, which is more adaptable.

[0100] According to a method for estimating the health status of a battery stack provided by the present invention, the relevant parameters include the maximum voltage value of a single cell and the minimum voltage value of a single cell; the battery stack is subjected to consistency detection according to the relevant parameters, and whether the battery stack meets the strategy switching start condition is determined based on the consistency detection result, including:

[0101] Determine the voltage deviation during the charge and discharge cycle according to the maximum voltage value of the single cell and the minimum voltage value of the single cell;

[0102] Based on the voltage deviation and the preset voltage deviation threshold, a consistency test result is determined; the consistency test result includes: the voltage consistency deviation is too large or the voltage consistency deviation is normal;

[0103] When the consistency detection result shows that the voltage consistency deviation is too large, it is determined that the battery stack meets the strategy switching start condition.

[0104] Specifically, in some embodiments, the specific implementation process of performing consistency detection on the battery stack according to relevant parameters and determining whether the battery stack meets the strategy switching start condition based on the consistency detection result in step 102 includes: battery stack single cell maximum voltage / minimum voltage deviation detection and battery cluster remaining capacity percentage value deviation. The following first describes the method of determining the consistency detection result by the battery stack single cell maximum voltage / minimum voltage deviation detection:

[0105] First, the voltage deviation in the charge and discharge cycle is determined according to the maximum voltage value and the minimum voltage value of the single cell, that is, the deviation between the maximum voltage and the minimum voltage of the single cell of the battery stack is obtained.

[0106] Further, based on the voltage deviation and a preset voltage deviation threshold, a consistency detection result is determined, the voltage deviation threshold reference is 400mv, and the consistency detection result includes: the voltage consistency deviation is too large or the voltage consistency deviation is normal.

[0107] Furthermore, when the consistency detection result shows that the voltage consistency deviation is too large, it is determined that the battery stack meets the strategy switching start-up conditions; conversely, when the consistency detection result shows that the voltage consistency deviation is normal, it is determined that the battery stack does not meet the strategy switching start-up conditions, and the short board effect is used to calculate the battery health status of the battery stack.

[0108] The method provided in this embodiment determines the consistency test result of the battery stack based on the maximum voltage / minimum voltage deviation detection of the battery stack single cell. When the consistency test results are inconsistent, the start-up strategy switching condition is determined, and it is further determined whether to use the ampere-hour integration method or the parameter identification method to calculate the battery health state of the battery stack. When the consistency test results are inconsistent, the short board effect is used to calculate the battery health state of the battery stack. The present invention calculates the battery health state of the battery stack based on the short board effect, the ampere-hour integration method and the parameter identification. It is suitable for the calculation of the battery health state under actual complex working conditions, and improves the accuracy of the calculation of the battery health state of the battery stack.

[0109] According to a method for estimating the health status of a battery stack provided by the present invention, the relevant parameters also include the operating status of the battery stack and the percentage value of the remaining capacity of each battery cluster under the battery stack; the battery stack is subjected to consistency detection according to the relevant parameters, and whether the battery stack meets the strategy switching start condition is determined based on the consistency detection result, including:

[0110] When the battery stack operation state changes from the static state to the charge and discharge stage, the remaining capacity percentage value of each battery cluster under the battery stack is determined;

[0111] Determine the deviation of the remaining capacity percentage value of each battery cluster according to the remaining capacity percentage value of each battery cluster under the battery stack;

[0112] Based on the remaining capacity percentage value deviation of each battery cluster and the preset remaining capacity percentage value deviation threshold, a consistency test result is determined; the consistency test result includes: the remaining capacity percentage value deviation consistency deviation of each battery cluster is too large or the remaining capacity percentage value deviation consistency deviation of each battery cluster is normal;

[0113] When the consistency detection result shows that the consistency deviation of the remaining capacity percentage values ​​of each battery cluster is too large, it is determined that the battery stack meets the policy switching start condition.

[0114] Specifically, in some embodiments, the specific implementation process of performing consistency detection on the battery stack according to relevant parameters and determining whether the battery stack meets the policy switching start condition based on the consistency detection result in step 102 includes: battery cluster remaining capacity percentage value deviation. The following first describes the method of determining the consistency detection result by detecting the battery cluster remaining capacity percentage value deviation:

[0115] First, when the operating state of the battery stack changes from the static stage to the charge and discharge stage, the remaining capacity percentage value of each battery cluster under the battery stack is determined, that is, the remaining capacity percentage value of each battery cluster under the battery stack is detected, and then, based on the remaining capacity percentage value of each battery cluster under the battery stack, the remaining capacity percentage value deviation of each battery cluster is determined, that is, the highest remaining capacity percentage value of the battery cluster and the lowest remaining capacity percentage value of the battery cluster are obtained.

[0116] Furthermore, based on the remaining capacity percentage value deviation of each battery cluster and a preset remaining capacity percentage value deviation threshold, a consistency detection result is determined; the consistency detection result includes: the remaining capacity percentage value deviation of each battery cluster is too large or the remaining capacity percentage value deviation of each battery cluster is normal.

[0117] When the consistency detection result shows that the consistency deviation of the remaining capacity percentage values ​​of each battery cluster is too large, that is, when the consistency detection result is inconsistent, it is determined that the battery stack meets the policy switching start condition.

[0118] The method provided in this embodiment determines the consistency detection result of the battery stack based on the deviation detection of the percentage value of the remaining capacity of the battery cluster. When the consistency detection results are inconsistent, the activation strategy switching condition is determined, and it is further determined whether to use the ampere-hour integration method or the parameter identification method to calculate the battery health state of the battery stack. When the consistency detection results are inconsistent, the short board effect is used to calculate the battery health state of the battery stack. The present invention calculates the battery health state of the battery stack based on the short board effect, the ampere-hour integration method and the parameter identification. It is suitable for calculating the battery health state under actual complex working conditions and improves the accuracy of the battery health state calculation of the battery stack.

[0119] According to a method for estimating the health status of a battery stack provided by the present invention, the relevant parameters also include the maximum temperature of a single cell and the minimum temperature of a single cell; determining whether the battery stack meets the target judgment condition includes:

[0120] Determine whether the battery stack meets the first-level judgment conditions based on relevant parameters; the first-level judgment conditions include: the maximum temperature of the single cell and the minimum temperature of the single cell in the whole charging and discharging stage are both within the effective temperature range; the maximum temperature of the single cell is determined based on the maximum temperature of the battery stack, and the minimum temperature of the single cell is determined based on the minimum temperature of the battery stack; and the absolute value of the difference between the initial remaining capacity percentage value and the ending remaining capacity percentage value in the charging or discharging stage of the battery stack and the cumulative capacity are both greater than the validity calculation deviation value;

[0121] When it is determined that the battery stack satisfies the primary judgment condition, and when it is determined that the battery stack satisfies at least one secondary judgment condition, it is determined that the battery stack satisfies the target judgment condition.

[0122] Specifically, in some embodiments, the specific implementation process of determining whether the battery stack meets the target judgment condition in step 103 includes the following steps:

[0123] First, determine whether the battery stack meets the first-level judgment conditions based on relevant parameters. The following are the first-level judgment conditions for outputting the battery health status value of the battery stack using the ampere-hour integration method, which must all be met:

[0124] (1) The maximum temperature of the single cell and the minimum temperature of the single cell during the entire charge and discharge stage are both within the effective temperature range; the maximum temperature of the single cell is determined based on the maximum temperature of the battery stack, and the minimum temperature of the single cell is determined based on the minimum temperature of the battery stack;

[0125] (2) In addition, the absolute value and cumulative capacity of the difference between the initial remaining capacity percentage value and the final remaining capacity percentage value during the charging or discharging phase of the battery stack are both greater than the validity calculation deviation value.

[0126] When the first-level judgment condition is met, any of the following second-level judgment conditions must also be met:

[0127] (1) When the battery stack is charged, the initial remaining capacity percentage value corresponding to the lowest single cell voltage is lower than the validity judgment threshold at the beginning of charging (reference threshold remaining capacity percentage value 12%) and there is a static duration that meets the required static duration (reference threshold 180 minutes), and the final remaining capacity percentage value corresponding to the highest single cell voltage at the end of charging of the battery stack is higher than the validity judgment threshold at the end of charging (reference threshold remaining capacity percentage value 92%) and the duration meets the required static duration;

[0128] (2) When the battery stack is charged, the lowest single cell voltage reaches the full discharge end condition required by the project in the previous discharge stage (reference threshold voltage 2.5V, corresponding to the remaining capacity percentage value 0%), and the ending remaining capacity percentage value corresponding to the highest single cell voltage at the end of charging of the battery stack is higher than the charging end validity judgment threshold and the duration meets the required static duration;

[0129] (3) When the battery stack is charged, the lowest single cell voltage reaches the full discharge end condition required by the project in the previous discharge stage, and the highest single cell voltage of the battery stack reaches the full charge end condition required by the project at the end of the current charge (reference threshold voltage 3.65V, corresponding to the remaining capacity percentage value of 100%);

[0130] (4) When the battery stack is discharged, the initial remaining capacity percentage value corresponding to the highest single cell voltage is higher than the validity judgment threshold at the beginning of discharge, and the battery stack static duration meets the required static duration threshold, and the final remaining capacity percentage value corresponding to the lowest single cell voltage at the end of discharge is lower than the validity judgment threshold at the end of discharge, and the duration meets the required static duration;

[0131] (5) When the battery stack is discharged, the highest single cell voltage reaches the full charge end condition required by the project in the previous charging stage, and the corresponding end remaining capacity percentage value of the lowest single cell voltage at the end of charging of the battery stack is lower than the end-of-discharge terminal effectiveness judgment threshold and the duration meets the required static duration;

[0132] (6) When the battery stack is discharged, the highest single cell voltage reaches the full charge end condition required by the project in the previous charging stage, and the lowest single cell voltage of the battery stack reaches the full discharge end condition required by the project at the end of the current discharge.

[0133] Further, when it is determined that the battery stack meets the primary judgment condition and when it is determined that the battery stack meets at least one secondary judgment condition, it is determined that the battery stack meets the target judgment condition. That is, when the battery stack related parameters meet the strategy switching condition and the ampere-hour integration method calculation condition.

[0134] The method provided in this embodiment calculates the current real battery stack health status value according to the ampere-hour integration method when the battery stack related parameters meet the strategy switching related start-up conditions but do not meet the target judgment conditions of the ampere-hour integration calculation. When the battery stack related parameters meet the strategy switching related start-up conditions but do not meet the target judgment conditions of the ampere-hour integration calculation, the parameter identification is used to calculate the current battery stack capacity value in real time during the charging and discharging process, and the ratio of the battery stack capacity value to the rated capacity value is used as the current battery stack real battery health status value. The present invention jointly performs battery stack battery health status calculation based on the short board effect, the ampere-hour integration method and parameter identification, which is suitable for battery health status calculation under actual complex working conditions, and improves the accuracy of battery stack battery health status calculation.

[0135] According to a method for estimating the health status of a battery stack provided by the present invention, the health status of a real battery stack battery is determined by an ampere-hour integration method, comprising:

[0136] Determine the initial remaining capacity percentage value that meets the strategy switching start condition, the ending remaining capacity percentage value that meets the strategy switching start condition, and the accumulated ampere-hour Ah value that meets the effective temperature range during the charging and discharging process;

[0137] Determining an absolute value of the ratio difference based on the initial remaining capacity percentage value and the ending remaining capacity percentage value;

[0138] Divide the absolute value of the ratio difference and the accumulated Ah value to determine the capacity value of the battery stack calculated by the current Ah integration method;

[0139] The health status of the real battery stack batteries is determined based on the capacity value of the battery stack, the rated value of the battery stack capacity value, the health status of the real battery stack batteries calculated by the short board effect of the current scheduling cycle, and the health status of the real battery stack batteries output in the previous scheduling cycle.

[0140] Specifically, in some embodiments, the specific implementation process of determining the health status of the actual battery stack battery by the ampere-hour integration method in step 104 includes the following steps:

[0141] First, determine the initial remaining capacity percentage value that meets the strategy switching start condition, the ending remaining capacity percentage value that meets the strategy switching start condition, and the accumulated ampere-hour Ah value that meets the effective temperature range during the charging and discharging process.

[0142] For example, ① record the initial remaining capacity percentage value that meets the strategy switching conditions, recorded as SOC1; ② record the cumulative Ah value that meets the temperature range conditions during the charging and discharging process, recorded as Ah; ③ record the ending remaining capacity percentage value that meets the strategy switching conditions, recorded as SOC2.

[0143] Furthermore, based on the initial remaining capacity percentage value SOC1 and the ending remaining capacity percentage value SOC2, the absolute value of the ratio difference is determined, and the absolute value of the ratio difference is divided by the accumulated ampere-hour value Ah to determine the capacity value Cap1 of the battery stack calculated by the current ampere-hour integration method. Then, based on the capacity value Cap1 of the battery stack, the rated value Cap of the battery stack capacity value, and the short board effect of the current scheduling cycle, the real battery stack battery health status is calculated. , the actual battery health status of the battery stack output in the previous scheduling cycle , determine the health status of the real battery stack cells.

[0144] For example, determine that the current |SOC1-SOC2|>effectiveness remaining capacity percentage difference absolute value judgment threshold and the accumulated Ah value>effectiveness accumulated capacity judgment threshold, calculate the current capacity and the real battery health status value according to the following formula, and take into account that the current ampere-hour integration method to calculate the real battery health status value should be limited to the real battery health status value of each cluster in the battery stack, and at the same time, when the current ampere-hour integration method calculation does not exceed the effective threshold (reference threshold 10Cycle) from the previous ampere-hour integration method calculation, the calculated value should not deviate too much. Therefore, the output upper limit is set to the lowest battery health status value of each battery cluster and the last ampere-hour integration calculation battery health status plus a fixed deviation (reference range 0.5%), and the lower limit is the last ampere-hour integration calculation SOH minus the fixed deviation (reference range 0.5%).

[0145]

[0146]

[0147] in, Indicates the capacity value of the current battery stack calculated by the current ampere-hour integration method. It indicates the rated value of the battery stack capacity, Ah indicates the cumulative Ah value that meets the effective temperature range requirements during the charge and discharge process, SOC1 indicates the initial remaining capacity percentage value that meets the strategy switching conditions, and SOC2 indicates the ending remaining capacity percentage value that meets the strategy switching conditions. Indicates the SOH output in the previous scheduling cycle. Indicates the SOH calculated based on the short board effect in the current scheduling period.

[0148] For example, Figure 3 FIG. 3 is a flow chart of the method for estimating the health status of a battery stack provided by the present invention. Figure 3 As shown, the method includes:

[0149] Step 301 : Collect parameters such as the current battery stack operating status, single cell voltage, single cell temperature, and battery stack total current.

[0150] Step 302: Determine whether the battery is left standing for 3 hours in a non-charging / discharging state.

[0151] If the execution result of step 302 is yes, step 303 is executed.

[0152] Step 303: Determine whether the cell OCV corresponds to SOC ≥ 93% or ≤ 20% at the moment before entering the charge / discharge state.

[0153] If the execution result of step 303 is yes, step 304 is executed.

[0154] Step 304: determine whether it is the first time to leave it still.

[0155] If the execution result of step 304 is yes, then step 305 is executed; if the execution result of step 304 is yes, then step 308 is executed.

[0156] Step 305: Record the SOC value corresponding to the current OCV, recorded as SOC1.

[0157] Step 306, after charging and discharging in the charging and discharging state, keep it still, record the accumulated ampere-hour value of this link, recorded as Ah; record the charging and discharging time of this link, recorded as t.

[0158] Step 307 , collecting parameters such as the current battery stack operating status, single cell voltage, single cell temperature, and battery stack total current.

[0159] Step 308: record the SOC value corresponding to the current OCV, recorded as SOC2; and simultaneously record the corresponding nominal capacity at the current temperature, recorded as Cap.

[0160] When the initial conditions are met, the battery charge and discharge capacity values ​​are accumulated in real time as the cumulative capacity value;

[0161] It is required that the temperature does not deviate from the application temperature during the charging and discharging process, and the nominal capacity corresponding to the highest temperature at the end is recorded. When the cumulative capacity value is greater than a certain confidence threshold, the cumulative capacity value can be confirmed as the cumulative judgment capacity value;

[0162] When the absolute value of the difference between the initial condition for determining the remaining capacity percentage value and the termination condition for determining the remaining capacity percentage value meets a certain confidence threshold, it can be confirmed as the difference in the remaining capacity percentage value.

[0163] Step 309: SOH=100 Ah / (|SOC1-SOC2| Cap), calculate the current battery stack SOH value.

[0164] In the method provided in this embodiment, when the battery stack related parameters meet the strategy switching conditions and do not meet the calculation conditions of the ampere-hour integration method, the health state of the real battery stack battery is determined by the ampere-hour integration method, firstly, the initial remaining capacity percentage value that meets the strategy switching start condition, the ending remaining capacity percentage value that meets the strategy switching start condition, and the cumulative ampere-hour Ah value that meets the effective temperature range during the charging and discharging process are determined; then, based on the initial remaining capacity percentage value and the ending remaining capacity percentage value, the absolute value of the ratio difference is determined, and the absolute value of the ratio difference is divided by the cumulative ampere-hour Ah value to determine the capacity value of the battery stack calculated by the current ampere-hour integration method; further, based on the capacity value of the battery stack, the rated value of the battery stack capacity value, the health state of the real battery stack battery calculated by the short board effect of the current scheduling cycle, and the health state of the real battery stack battery output in the previous scheduling cycle, the health state of the real battery stack battery is determined. The present invention jointly calculates the health state of the battery stack battery according to the short board effect, the ampere-hour integration method, and the parameter identification method, which is suitable for battery health state calculation under actual complex working conditions, and improves the accuracy of battery health state estimation of the battery stack battery.

[0165] According to a method for estimating the health status of a battery stack provided by the present invention, determining an initial remaining capacity percentage value that satisfies a strategy switching start condition includes:

[0166] When in the charging state, when the lowest voltage value of the single cell meets the judgment threshold and the standing time meets the OCV voltage sampling standing time, the remaining capacity percentage value corresponding to the cell voltage is determined as the initial remaining capacity percentage value;

[0167] When in the charging state, when the lowest voltage value of the single cell reaches the full discharge cut-off voltage condition in the previous discharge cycle, 0% is determined as the initial remaining capacity percentage value;

[0168] When in the discharge state, when the highest voltage value of the single cell meets the judgment threshold and the standing time meets the OCV voltage sampling standing time, the remaining capacity percentage value corresponding to the highest cell is determined as the initial remaining capacity percentage value;

[0169] When in the discharge state, when the highest voltage value of the single cell reaches the full charge cut-off voltage condition in the previous charging cycle, 100% is determined as the initial remaining capacity percentage value.

[0170] In the method provided in this embodiment, the manners of obtaining the initial remaining capacity percentage value are different under different conditions, and the estimation method has higher adaptability.

[0171] According to a method for estimating the health status of a battery stack provided by the present invention, determining a final remaining capacity percentage value that satisfies a strategy switching start condition includes:

[0172] When the charging is finished, when the highest voltage value of the single cell meets the judgment threshold and the standing time meets the OCV voltage sampling standing time, the remaining capacity percentage value corresponding to the highest cell is used as the termination condition for judging the remaining capacity percentage;

[0173] When the charging is finished and the highest voltage of the single cell reaches the full charge cut-off voltage condition, 100% is determined as the ending remaining capacity percentage value;

[0174] When the discharge is finished, when the lowest voltage value of the single cell meets the judgment threshold and the standing time meets the OCV voltage sampling standing time, the remaining capacity percentage value corresponding to the lowest cell is determined as the ending remaining capacity percentage value;

[0175] When the discharge is terminated and the minimum cell voltage of the battery stack reaches the full discharge cut-off voltage condition, 0% is determined as the ending remaining capacity percentage value.

[0176] In the method provided in this embodiment, the manners of obtaining the ending remaining capacity percentage value are different under different states, and the estimation method has higher adaptability.

[0177] According to a method for estimating the health status of a battery stack provided by the present invention, the relevant parameters also include the total current of the battery stack; determining the health status of the actual battery stack battery by a parameter identification method includes:

[0178] Determine the rated value of the battery stack capacity at the current temperature according to the battery stack operating status, the total battery stack current, the single cell voltage value and the single cell temperature;

[0179] The health status of the actual battery stack cells is determined based on the current remaining capacity percentage value of the battery stack at the current temperature and the rated value of the battery stack capacity value at the current temperature.

[0180] Specifically, in some embodiments, the specific implementation process of determining the health status of the actual battery stack battery by the parameter identification method in step 105 includes the following steps:

[0181] First, determine the rated value of the battery stack capacity at the current temperature based on the battery stack operating status, the total battery stack current, the single cell voltage value, and the single cell temperature. When the battery stack related parameters meet the strategy switching conditions but do not meet the ampere-hour integration method calculation conditions, perform parameter identification calculations in real time according to the following formula during the charging and discharging process (the relevant calculation values ​​will be affected by temperature, remaining capacity percentage correction strategy, etc., so it is necessary to set upper and lower step limits on each ampere-hour correction initial value. If there is no ampere-hour correction initial value when the first parameter identification link is run, it is not necessary to consider it). For example, refer to the following formula to determine the rated value of the battery stack capacity at the current temperature:

[0182]

[0183] in Indicates the rated value of the battery stack capacity at the current temperature. Indicates the change value of soc in the selected unit time, Indicates the ampere-hour conversion value in the selected unit time.

[0184] Furthermore, the health status of the actual battery stack battery can be determined based on the current remaining capacity percentage value of the battery stack at the current temperature and the rated value of the battery stack capacity value at the current temperature. For example, the ratio of the current remaining capacity percentage value to the rated value of the battery stack capacity value at the current temperature is calculated, and the SOH value of the battery stack at the current temperature is determined based on the ratio.

[0185] For example, Figure 4 FIG. 4 is a flow chart of a method for estimating the health status of a battery stack provided by the present invention. Figure 4 As shown, the method includes:

[0186] Step 401: Collect relevant parameters such as the current battery stack operating status, single cell voltage, single cell temperature, and battery stack total current.

[0187] Step 402: According to the formula 0=dAh / (dt cap)+dSOC / dt, and use parameter identification to calculate the real-time rated capacity value cap at the current temperature.

[0188] Step 403: Calculate the SOH value of the battery stack at the current temperature by using the current capacity value and the rated capacity value cap at the current temperature.

[0189] In the method provided in this embodiment, when the battery stack related parameters meet the strategy switching conditions but do not meet the target judgment conditions, that is, the ampere-hour integration method calculation conditions, the health status of the actual battery stack battery is determined by the parameter identification method. The present invention calculates the battery stack battery health status based on the short board effect, the ampere-hour integration method and the parameter identification method. It is suitable for battery health status calculation under actual complex working conditions and improves the accuracy of battery stack battery health status estimation.

[0190] Optionally, when the battery stack calculates the battery health status value strategy, a jump phenomenon may occur because the real battery health status value is strongly related to the current state of the battery stack (temperature, voltage platform, current, etc.). In order to ensure the normal use of the system, it is necessary to add a display battery health status value to participate in the internal state calculation and display. The relationship between the display battery health status and the real battery health status value includes:

[0191] ①The actual battery health status value can jump, but the displayed battery health status value cannot jump;

[0192] ② The actual battery health status value may increase, but the displayed battery health status value cannot change upward, and can only remain unchanged or slowly decrease;

[0193] ③ After the actual battery health status value jumps downward, the displayed battery health status value rapidly decreases at a fixed rate following the deviation from the actual battery health status value.

[0194] The health status estimation device of the battery stack provided by the present invention is described below. The health status estimation device of the battery stack described below and the health status estimation method of the battery stack described above can be referenced to each other.

[0195] Figure 5 is a schematic diagram of the structure of the health status estimation device of the battery stack provided by the present invention, such as Figure 5 As shown, the health status estimation device 500 of the battery stack battery includes the following modules:

[0196] An acquisition module 510 is used to acquire relevant parameters of the battery stack;

[0197] A strategy switching module 520, configured to perform consistency detection on the battery stack according to the relevant parameters, and determine whether the battery stack satisfies a strategy switching start condition based on the consistency detection result; the strategy switching start condition is used to indicate a condition where the consistency deviation of the battery stack exceeds a preset range;

[0198] In the case where it is determined that the battery stack satisfies the strategy switching start condition, determining whether the battery stack satisfies a target judgment condition; the target judgment condition is used to indicate that the battery stack satisfies a condition for calculating a battery health status of the battery stack through ampere-hour integration;

[0199] An evaluation module 530, configured to determine the health status of the actual battery stack battery by an ampere-hour integration method when it is determined that the battery stack meets the target judgment condition;

[0200] When it is determined that the battery stack does not meet the target judgment condition, the health status of the actual battery stack cells is determined by a parameter identification method.

[0201] The device provided in this embodiment includes an acquisition module 510, a strategy switching module 520 and an evaluation module 530, wherein the acquisition module 510 is used to acquire relevant parameters of the battery stack, wherein the relevant parameters include the battery stack operating state, the total current of the battery stack, the maximum voltage value of the single cell, the minimum voltage value of the single cell, the battery health state value of each battery cluster, the remaining capacity percentage value of each battery cluster under the battery stack, the maximum temperature of the battery stack and the minimum temperature of the battery stack; then, the strategy switching module 520 is used to perform consistency detection on the battery stack according to the relevant parameters, and determine whether the battery stack meets the strategy switching start condition based on the consistency detection result, the strategy switching start condition is used to characterize the condition that the consistency deviation of the battery stack exceeds a preset range, and when it is determined that the battery stack meets the strategy switching start condition, determine whether the battery stack meets the target judgment condition, the target judgment condition is used to characterize the condition that the battery stack meets the condition that the battery stack meets the battery health state calculated by the ampere-hour integration; further, the evaluation module 530 is used to determine the real battery stack battery health state by the ampere-hour integration method when it is determined that the battery stack meets the target judgment condition; when it is determined that the battery stack does not meet the target judgment condition, determine the real battery stack battery health state by the parameter identification method.

[0202] In the present invention, relevant parameters of the battery stack are first obtained, and it is clarified that the ampere-hour integration method is used when the strategy switching start-up conditions and the target judgment conditions are met. The target judgment conditions are used to characterize that the battery stack meets the conditions for calculating the battery health status of the battery stack through ampere-hour integration, so as to avoid excessive calculations of the ampere-hour integration method under normal conditions, which may lead to multiple abnormal changes in the BAU-level battery health status value. At the same time, the real battery health status of the battery stack is estimated based on the highest voltage and the lowest voltage of the single cell in the entire battery stack, so as to ensure that the real battery health status value of the battery stack can be estimated when there is a consistency deviation in the battery. The present invention is suitable for calculating the battery health status of the battery stack under actual complex working conditions, which improves the accuracy of the battery health status estimation of the battery stack.

[0203] According to a battery stack battery health status estimation device 500 provided by the present invention, the relevant parameters include a maximum voltage value of a single cell and a minimum voltage value of a single cell; the strategy switching module 520 is specifically used to:

[0204] Determining a voltage deviation in a charge-discharge cycle according to the maximum voltage value of the single cell and the minimum voltage value of the single cell;

[0205] Based on the voltage deviation and a preset voltage deviation threshold, determining the consistency detection result; the consistency detection result includes: the voltage consistency deviation is too large or the voltage consistency deviation is normal;

[0206] When the consistency detection result is that the voltage consistency deviation is too large, it is determined that the battery stack meets the strategy switching start condition.

[0207] According to a battery stack battery health status estimation device 500 provided by the present invention, the related parameters also include the battery stack operation status and the remaining capacity percentage value of each battery cluster in the battery stack; the strategy switching module 520 is also used for:

[0208] When the operating state of the battery stack changes from a static state to a charge and discharge stage, determining a percentage value of a remaining capacity of each battery cluster under the battery stack;

[0209] Determining the deviation of the remaining capacity percentage value of each battery cluster according to the remaining capacity percentage value of each battery cluster under the battery stack;

[0210] Based on the residual capacity percentage value deviation of each battery cluster and a preset residual capacity percentage value deviation threshold, the consistency detection result is determined; the consistency detection result includes: the residual capacity percentage value deviation consistency deviation of each battery cluster is too large or the residual capacity percentage value deviation consistency deviation of each battery cluster is normal;

[0211] When the consistency detection result is that the consistency deviation of the remaining capacity percentage values ​​of each battery cluster is too large, it is determined that the battery stack meets the strategy switching start condition.

[0212] According to a battery stack battery health status estimation device 500 provided by the present invention, the related parameters also include the maximum temperature of the single cell and the minimum temperature of the single cell; the strategy switching module 520 is also used for:

[0213] Determine whether the battery stack meets the first-level judgment condition based on the relevant parameters; the first-level judgment condition includes: the maximum temperature of the single cell and the minimum temperature of the single cell in the whole charging and discharging stage are both within the effective temperature range; the maximum temperature of the single cell is determined based on the maximum temperature of the battery stack, and the minimum temperature of the single cell is determined based on the minimum temperature of the battery stack; and the absolute value of the difference between the initial remaining capacity percentage value and the ending remaining capacity percentage value in the charging or discharging stage of the battery stack and the cumulative capacity are both greater than the validity calculation deviation value;

[0214] When it is determined that the battery stack satisfies the primary judgment condition, and when it is determined that the battery stack satisfies at least one secondary judgment condition, it is determined that the battery stack satisfies the target judgment condition.

[0215] According to a device 500 for estimating the health status of a battery stack provided by the present invention, the evaluation module 530 is specifically used for:

[0216] Determine the initial remaining capacity percentage value that satisfies the strategy switching start condition, the ending remaining capacity percentage value that satisfies the strategy switching start condition, and the accumulated ampere-hour Ah value that satisfies the effective temperature range during the charging and discharging process;

[0217] Determining an absolute value of a ratio difference based on the initial remaining capacity percentage value and the ending remaining capacity percentage value;

[0218] Dividing the absolute value of the ratio difference by the accumulated ampere-hour Ah value to determine the capacity value of the battery stack calculated by the current ampere-hour integration method;

[0219] The health status of the real battery stack battery is determined based on the capacity value of the battery stack, the rated value of the battery stack capacity value, the health status of the real battery stack battery calculated by the short board effect of the current scheduling cycle, and the health status of the real battery stack battery output in the previous scheduling cycle.

[0220] According to a device 500 for estimating the health status of a battery stack provided by the present invention, the evaluation module 530 is specifically used for:

[0221] When in a charging state, when the lowest voltage value of the single cell meets the judgment threshold and the standing time meets the OCV voltage sampling standing time, the remaining capacity percentage value corresponding to the cell voltage is determined as the initial remaining capacity percentage value;

[0222] When in a charging state, when the lowest voltage value of the single cell reaches the full discharge cut-off voltage condition in the previous discharge cycle, 0% is determined as the initial remaining capacity percentage value;

[0223] When in a discharging state, when the highest voltage value of the single cell meets the judgment threshold and the standing time meets the OCV voltage sampling standing time, the remaining capacity percentage value corresponding to the highest cell is determined as the initial remaining capacity percentage value;

[0224] When in a discharging state, when the highest voltage value of the single cell reaches the full charge cut-off voltage condition in the previous charging cycle, 100% is determined as the initial remaining capacity percentage value.

[0225] According to a device 500 for estimating the health status of a battery stack provided by the present invention, the evaluation module 530 is specifically used for:

[0226] When the charging is finished, when the highest voltage value of the single cell meets the judgment threshold and the standing time meets the OCV voltage sampling standing time, the remaining capacity percentage value corresponding to the highest cell is used as the termination condition for judging the remaining capacity percentage;

[0227] When the charging is finished and the highest voltage value of the single cell reaches the full charge cut-off voltage condition, 100% is determined as the ending remaining capacity percentage value;

[0228] When the discharge is terminated, when the lowest voltage value of the single cell meets the judgment threshold and the rest time meets the OCV voltage sampling rest time, the remaining capacity percentage value corresponding to the lowest cell is determined as the ending remaining capacity percentage value;

[0229] When the discharge is terminated and the lowest cell voltage of the battery stack reaches the full discharge cut-off voltage condition, 0% is determined as the final remaining capacity percentage value.

[0230] According to a health status estimation device 500 for a battery stack provided by the present invention, the related parameters also include the total current of the battery stack; the evaluation module 530 is specifically used for:

[0231] Determine the rated value of the battery stack capacity value at the current temperature according to the battery stack operating state, the battery stack total current, the single cell voltage value and the single cell temperature;

[0232] The health status of the actual battery stack battery is determined based on the current remaining capacity percentage value of the battery stack at the current temperature and the rated value of the battery stack capacity value at the current temperature.

[0233] Figure 6 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 6 As shown, the electronic device may include: a processor 610, a communication interface 620, a memory 630 and a communication bus 640, wherein the processor 610, the communication interface 620 and the memory 630 communicate with each other through the communication bus 640. The processor 610 may call the logic instructions in the memory 630 to execute the health status estimation method of the battery stack battery, and the method includes:

[0234] Obtain relevant parameters of the battery stack;

[0235] Performing consistency detection on the battery stack according to the relevant parameters, and determining whether the battery stack meets the strategy switching start condition based on the consistency detection result; the strategy switching start condition is used to characterize the condition that the consistency deviation of the battery stack exceeds a preset range;

[0236] In the case where it is determined that the battery stack satisfies the strategy switching start condition, determining whether the battery stack satisfies a target judgment condition; the target judgment condition is used to indicate that the battery stack satisfies a condition for calculating a battery health status of the battery stack through ampere-hour integration;

[0237] When it is determined that the battery stack meets the target judgment condition, determining the health status of the real battery stack battery by using the ampere-hour integration method;

[0238] When it is determined that the battery stack does not meet the target judgment condition, the health status of the actual battery stack cells is determined by a parameter identification method.

[0239] In addition, the logic instructions in the above-mentioned memory 630 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0240] On the other hand, the present invention further provides a computer program product, the computer program product comprising a computer program, the computer program can be stored in a non-transitory computer-readable storage medium, when the computer program is executed by a processor, the computer can execute the health status estimation method of the battery stack provided by the above methods, the method comprising:

[0241] Obtain relevant parameters of the battery stack;

[0242] Performing consistency detection on the battery stack according to the relevant parameters, and determining whether the battery stack meets the strategy switching start condition based on the consistency detection result; the strategy switching start condition is used to characterize the condition that the consistency deviation of the battery stack exceeds a preset range;

[0243] In the case where it is determined that the battery stack satisfies the strategy switching start condition, determining whether the battery stack satisfies a target judgment condition; the target judgment condition is used to indicate that the battery stack satisfies a condition for calculating a battery health status of the battery stack through ampere-hour integration;

[0244] When it is determined that the battery stack meets the target judgment condition, determining the health status of the real battery stack battery by using the ampere-hour integration method;

[0245] When it is determined that the battery stack does not meet the target judgment condition, the health status of the actual battery stack cells is determined by a parameter identification method.

[0246] In another aspect, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, which is implemented when the computer program is executed by a processor to perform the health status estimation method of the battery stack provided by the above methods, the method comprising:

[0247] Obtain relevant parameters of the battery stack;

[0248] Performing consistency detection on the battery stack according to the relevant parameters, and determining whether the battery stack meets the strategy switching start condition based on the consistency detection result; the strategy switching start condition is used to characterize the condition that the consistency deviation of the battery stack exceeds a preset range;

[0249] In the case where it is determined that the battery stack satisfies the strategy switching start condition, determining whether the battery stack satisfies a target judgment condition; the target judgment condition is used to indicate that the battery stack satisfies a condition for calculating a battery health status of the battery stack through ampere-hour integration;

[0250] When it is determined that the battery stack meets the target judgment condition, determining the health status of the real battery stack battery by using the ampere-hour integration method;

[0251] When it is determined that the battery stack does not meet the target judgment condition, the health status of the actual battery stack cells is determined by a parameter identification method.

[0252] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0253] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0254] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for estimating the health status of a battery stack, characterized in that: include: Obtain relevant parameters of the battery stack; Performing consistency detection on the battery stack according to the relevant parameters, and determining whether the battery stack meets the strategy switching start condition based on the consistency detection result; The strategy switching start condition is used to characterize the condition that the consistency deviation of the battery stack exceeds the preset range; the relevant parameters include the battery stack operating state, the total current of the battery stack, the maximum voltage value of the single cell, the minimum voltage value of the single cell, the battery health status value of each battery cluster, the remaining capacity percentage SOC value of each battery cluster under the battery stack, the maximum temperature of the battery stack, the minimum temperature of the battery stack, the maximum temperature of the single cell and the minimum temperature of the single cell; The determining whether the battery stack meets the strategy switching start-up condition based on the consistency detection result includes: determining that the battery stack meets the strategy switching start-up condition when the consistency detection result is that the consistency deviation of the remaining capacity percentage value of each battery cluster is too large; In the case where it is determined that the battery stack satisfies the strategy switching start condition, determining whether the battery stack satisfies a target judgment condition; the target judgment condition is used to indicate that the battery stack satisfies a condition for calculating a battery health status of the battery stack through ampere-hour integration; The determining whether the battery stack meets a target judgment condition includes: Determine whether the battery stack meets the first-level judgment condition based on the relevant parameters; the first-level judgment condition includes: the maximum temperature of the single cell and the minimum temperature of the single cell in the whole charging and discharging stage are both within the effective temperature range; the maximum temperature of the single cell is determined based on the maximum temperature of the battery stack, and the minimum temperature of the single cell is determined based on the minimum temperature of the battery stack; and the absolute value of the difference between the initial remaining capacity percentage value and the ending remaining capacity percentage value in the charging or discharging stage of the battery stack and the cumulative capacity are both greater than the validity calculation deviation value; In the case where it is determined that the battery stack satisfies the primary judgment condition, and in the case where it is determined that the battery stack satisfies at least one secondary judgment condition, determining that the battery stack satisfies the target judgment condition; When it is determined that the battery stack meets the target judgment condition, the health state of the battery in the real battery stack is determined by the ampere-hour integration method; when it is determined that the battery stack does not meet the target judgment condition, the health state of the battery in the real battery stack is determined by the parameter identification method.

2. The method for estimating the health status of a battery stack according to claim 1, characterized in that: The performing consistency detection on the battery stack according to the relevant parameters, and determining whether the battery stack meets the strategy switching start condition based on the consistency detection result, includes: Determining a voltage deviation in a charge-discharge cycle according to the maximum voltage value of the single cell and the minimum voltage value of the single cell; Based on the voltage deviation and a preset voltage deviation threshold, determining the consistency detection result; the consistency detection result includes: the voltage consistency deviation is too large or the voltage consistency deviation is normal; When the consistency detection result is that the voltage consistency deviation is too large, it is determined that the battery stack meets the strategy switching start condition.

3. The method for estimating the health status of a battery stack according to claim 1, characterized in that: The performing consistency detection on the battery stack according to the relevant parameters includes: When the operating state of the battery stack changes from a static state to a charge and discharge stage, determining a percentage value of a remaining capacity of each battery cluster under the battery stack; Determining the deviation of the remaining capacity percentage value of each battery cluster according to the remaining capacity percentage value of each battery cluster under the battery stack; The consistency detection result is determined based on the remaining capacity percentage value deviation of each battery cluster and a preset remaining capacity percentage value deviation threshold; the consistency detection result includes: the remaining capacity percentage value deviation consistency deviation of each battery cluster is too large or the remaining capacity percentage value deviation consistency deviation of each battery cluster is normal.

4. The method for estimating the health status of a battery stack according to claim 1, characterized in that: The method of determining the health status of a real battery stack battery by using the ampere-hour integration method includes: Determine the initial remaining capacity percentage value that satisfies the strategy switching start condition, the ending remaining capacity percentage value that satisfies the strategy switching start condition, and the accumulated ampere-hour Ah value that satisfies the effective temperature range during the charging and discharging process; Determining an absolute value of a ratio difference based on the initial remaining capacity percentage value and the ending remaining capacity percentage value; Dividing the absolute value of the ratio difference by the accumulated ampere-hour Ah value to determine the capacity value of the battery stack calculated by the current ampere-hour integration method; The health status of the real battery stack battery is determined based on the capacity value of the battery stack, the rated value of the battery stack capacity value, the health status of the real battery stack battery calculated by the short board effect of the current scheduling cycle, and the health status of the real battery stack battery output in the previous scheduling cycle.

5. The method for estimating the health status of a battery stack according to claim 4, characterized in that: The determining of the initial remaining capacity percentage value that satisfies the policy switching start condition includes: When in a charging state, when the lowest voltage value of a single cell meets the judgment threshold and the standing time meets the OCV voltage sampling standing time, the remaining capacity percentage value corresponding to the cell voltage is determined as the initial remaining capacity percentage value; When in a charging state, when the lowest voltage value of the single cell reaches the full discharge cut-off voltage condition in the previous discharge cycle, 0% is determined as the initial remaining capacity percentage value; When in a discharging state, when the highest voltage value of a single cell meets the judgment threshold and the standing time meets the OCV voltage sampling standing time, the remaining capacity percentage value corresponding to the highest cell is determined as the initial remaining capacity percentage value; When in a discharging state, when the highest voltage value of the single cell reaches the full charge cut-off voltage condition in the previous charging cycle, 100% is determined as the initial remaining capacity percentage value.

6. The method for estimating the health status of a battery stack according to claim 4, characterized in that: The determining of the ending remaining capacity percentage value that satisfies the policy switching start condition includes: When the charging is finished, when the highest voltage value of the single cell meets the judgment threshold and the standing time meets the OCV voltage sampling standing time, the remaining capacity percentage value corresponding to the highest cell is used as the termination condition for judging the remaining capacity percentage; When the charging is finished and the highest voltage value of the single cell reaches the full charge cut-off voltage condition, 100% is determined as the ending remaining capacity percentage value; When the discharge is terminated, the lowest voltage value of the single cell meets the judgment threshold and the standstill time meets the OCV voltage sampling standstill time, the remaining capacity percentage value corresponding to the lowest cell is determined as the ending remaining capacity percentage value; When the discharge is terminated and the lowest cell voltage of the battery stack reaches the full discharge cut-off voltage condition, 0% is determined as the final remaining capacity percentage value.

7. The method for estimating the health status of a battery stack according to claim 1, characterized in that: The related parameters also include the total current of the battery stack; the health status of the actual battery stack battery is determined by the parameter identification method, including: Determine the rated value of the battery stack capacity value at the current temperature according to the battery stack operating state, the battery stack total current, the single cell voltage value and the single cell temperature; The health status of the actual battery stack cells is determined based on the current remaining capacity percentage value of the battery stack at the current temperature and the rated value of the battery stack capacity value at the current temperature.

8. A device for estimating the health status of a battery stack, characterized in that: The method for estimating the health status of a battery stack cell according to any one of claims 1 to 7 is performed, wherein the device comprises: An acquisition module is used to obtain relevant parameters of the battery stack; A strategy switching module, used to perform consistency detection on the battery stack according to the relevant parameters, and determine whether the battery stack meets the strategy switching start-up conditions based on the consistency detection results; the strategy switching start-up conditions are used to characterize the conditions under which the consistency deviation of the battery stack exceeds a preset range; the relevant parameters include the battery stack operating status, the total current of the battery stack, the maximum voltage value of the single cell, the minimum voltage value of the single cell, the battery health status value of each battery cluster, the remaining capacity percentage SOC value of each battery cluster under the battery stack, the maximum temperature of the battery stack, the minimum temperature of the battery stack, the maximum temperature of the single cell and the minimum temperature of the single cell; the determination of whether the battery stack meets the strategy switching start-up conditions based on the consistency detection results includes: when the consistency detection result is that the consistency deviation of the remaining capacity percentage value of each battery cluster is too large, determining that the battery stack meets the strategy switching start-up conditions; In the case where it is determined that the battery stack satisfies the strategy switching start-up condition, determine whether the battery stack satisfies the target judgment condition; the target judgment condition is used to characterize that the battery stack satisfies the condition for calculating the battery health status of the battery stack through ampere-hour integration; the determination of whether the battery stack satisfies the target judgment condition includes: determining whether the battery stack satisfies the first-level judgment condition based on the relevant parameters; the first-level judgment condition includes: the maximum temperature of the single cell and the minimum temperature of the single cell in the whole charging and discharging stage are both within the effective temperature range; the maximum temperature of the single cell is determined based on the maximum temperature of the battery stack, and the minimum temperature of the single cell is determined based on the minimum temperature of the battery stack; and the absolute value of the difference between the initial remaining capacity percentage value and the ending remaining capacity percentage value in the charging or discharging stage of the battery stack and the cumulative capacity are both greater than the validity calculation deviation value; in the case where it is determined that the battery stack satisfies the first-level judgment condition, and in the case where it is determined that the battery stack satisfies at least one of the second-level judgment conditions, determine that the battery stack satisfies the target judgment condition; An evaluation module, configured to determine the health status of the actual battery stack battery by an ampere-hour integration method when it is determined that the battery stack meets the target judgment condition; When it is determined that the battery stack does not meet the target judgment condition, the health status of the actual battery stack cells is determined by a parameter identification method.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the method for estimating the health status of a battery stack cell according to any one of claims 1 to 7 is implemented.

Images