A battery pack intelligent balancing control method, system and storage medium

Abstract

The present invention discloses a battery pack intelligent balancing control method, system and storage medium, which relate to the field of battery technology. By deploying multiple groups of sensors in the battery pack and combining a transient current pulse method, the internal resistance information of each single cell is monitored in real time. By analyzing the transient response voltage information data, a battery attenuation warning instruction is issued according to the calculated internal resistance Rdt value of each single cell. Then, the self-discharge status of the marked single cells is collected to obtain battery self-discharge information data and battery polarization voltage information data to fit the attenuation degree evaluation index Zpg. Finally, the index is compared with a set evaluation threshold P to determine whether the attenuation degree of the marked battery is normal, and an active balancing control instruction is triggered accordingly. The induction coil technology is used to perform balancing control on the abnormally attenuated single cells to ensure the overall performance and safety of the battery pack.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to a battery pack intelligent balancing control method, system and storage medium. Background Art

[0002] With the rapid development of electric vehicles and energy storage systems, the demand for large-capacity and high-performance battery packs continues to increase. As the core energy storage unit, the performance of the battery pack directly affects the stability and life of the entire system. However, due to the differences between battery cells, including capacity, internal resistance and self-discharge rate, battery packs will experience imbalance problems during use. In order to improve the efficiency of battery packs, extend their life and ensure their safety, battery pack balancing control technology has received widespread attention.

[0003] In the Chinese invention patent application publication number CN108110336A, a battery pack balancing control method, device and equipment are disclosed. The control method sets a balancing start threshold corresponding to the battery pack's state of charge (SOC); determines the cells to be balanced in the battery pack using the voltage values ​​of the individual cells in the battery pack in a static state and the minimum voltage value of the individual cells in the battery pack; calculates the time required for balancing the cells to be balanced based on the voltage values ​​of the cells to be balanced and the imbalance degree of the cells to be balanced, and performs balancing on the cells to be balanced according to the balancing time required, where the imbalance degree is used to represent the difference between the SOC of the individual cells in the battery pack and the minimum SOC of the individual cells.

[0004] However, although the above-mentioned battery pack balancing control method can improve the accuracy of the overall balancing judgment of the battery pack, it lacks analysis and judgment of the attenuation of the single cells in the battery pack. Due to the long-term use of the battery pack, each single cell will show different attenuation trends, especially the influence of factors such as increased internal resistance, increased self-discharge rate and change in polarization voltage, which will cause imbalance in the overall battery pack. These imbalances cause some batteries in the battery pack to be subjected to greater pressure during the charging and discharging process, accelerate their aging, and even affect the safety of the battery pack. Summary of the Invention

[0005] In view of the deficiencies in the prior art, the present invention provides a battery pack intelligent balancing control method, system and storage medium, which solve the problems in the above-mentioned background technology.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: a battery pack intelligent balancing control system, including a single cell monitoring module, an internal resistance analysis and screening module, a decay evaluation module and an active balancing control module;

[0007] The single cell monitoring module is based on multiple sets of sensors deployed in the battery pack and combines the transient current pulse method to monitor the internal resistance information of each single cell in the battery pack and obtain transient response voltage information data;

[0008] The internal resistance analysis and screening module is used to analyze the transient response voltage information data to obtain the internal resistance Rdt of the corresponding single battery, mark the unhealthy single battery screened out according to the internal resistance Rdt value of each single battery, and issue a battery degradation warning instruction;

[0009] The attenuation assessment module is configured to, upon receiving a battery attenuation warning instruction, collect self-discharge status information of marked single cells in a stationary battery pack to obtain battery self-discharge information data, and collect battery polarization voltage information data based on voltage changes of the marked single cells from the initial charge and discharge stage to the stable stage. The attenuation assessment index Zpg is obtained by fitting by analyzing the battery self-discharge information data and the battery polarization voltage information data and correlating them with the internal resistance Rdt of the marked single cells;

[0010] The active balancing control module is used to compare and analyze the attenuation evaluation index Zpg with the set evaluation threshold P to determine whether the attenuation degree of the marked single battery is normal, trigger the active balancing control instruction, and combine the induction coil balancing method to perform balancing control on the marked single battery in the battery pack with abnormal attenuation status.

[0011] Preferably, the single cell monitoring module includes a deployment unit and an internal resistance monitoring unit;

[0012] The deployment unit is used to install multiple sets of sensors between each single cell in the lithium-ion battery pack, including voltage sensors and current sensors;

[0013] The internal resistance monitoring unit is used to apply a short and known current pulse to each single cell, monitor the transient response voltage information of each single cell in the battery pack through the transient response of the single cell voltage, and obtain transient response voltage information data. The transient response voltage information data includes the pre-transient response voltage value Vqs and the post-steady-state drop voltage value Vhs of each single cell.

[0014] Preferably, the internal resistance analysis and screening module includes an internal resistance analysis unit and a screening unit;

[0015] The internal resistance analysis unit is used to analyze the transient response voltage information data and calculate using Ohm's law to obtain the internal resistance Rdt of the corresponding single cell. i For example, it is obtained in the following way:

[0016] ;

[0017] Where, It is represented as the transient response voltage value of the ith single cell. It is expressed as the post-steady-state drop voltage value of the i-th single cell, Expressed as the current pulse value applied to each single cell;

[0018] According to the above, the internal resistance of the i-th single cell is obtained The internal resistance Rdt of several groups of single cells is obtained respectively, and the mean internal resistance Rdt of several groups of single cells is calculated based on the statistical mean value algorithm. avg ;

[0019] The screening unit is used to compare the internal resistance Rdt of several groups of single cells with the average internal resistance Rdt of the single cells. avg Compare the size and obtain the average internal resistance Rdt of the battery avg The internal resistance Rdt of the corresponding single battery is measured, and the corresponding unhealthy single batteries are screened out and marked, and a battery degradation warning instruction is issued.

[0020] Preferably, the attenuation evaluation module includes an information acquisition unit, a self-discharge analysis unit, a polarization voltage analysis unit and an overall attenuation evaluation unit;

[0021] The information acquisition unit is used to monitor the self-discharge status of marked single cells in the battery pack after a long period of rest in real time through multiple sets of sensors installed between the single cells in the lithium-ion battery pack after receiving the battery degradation warning instruction, and obtain battery self-discharge information data, wherein the battery self-discharge information data includes the voltage value of each marked single cell before rest. And the voltage value after static , and based on the voltage changes of the marked single cells from the initial stage of charge and discharge to the stable stage, collect battery polarization voltage information data, the battery polarization voltage information data includes the battery terminal instantaneous voltage value Vss and open circuit voltage value Vkk of each marked single cell.

[0022] Preferably, the self-discharge analysis unit is used to analyze the obtained battery self-discharge information data, obtain the self-discharge rate Dfd of several groups of marked single cells, and use the self-discharge rate Dfd of the jth marked single cell as the value. j For example, it is obtained in the following way:

[0023] ;

[0024] Where, It is represented by the voltage value of the jth marked single cell before standing, It is represented by the voltage value of the jth marked single cell after standing, Indicates the length of time it takes to rest.

[0025] Preferably, the polarization voltage analysis unit is used to analyze the obtained battery polarization voltage information data, obtain the polarization voltage values ​​Vjh of several groups of marked single cells, and use the polarization voltage value Vjh of the jth marked single cell as the value. j For example, it is obtained in the following way:

[0026] ;

[0027] Where, It is represented by the instantaneous voltage value of the battery terminal of the jth marked single cell. It is expressed as the open circuit voltage value of the jth marked single cell.

[0028] Preferably, the total attenuation evaluation unit is used to analyze the battery self-discharge information data and the battery polarization voltage information data, and associate them with the marked single cell internal resistance Rdt, and after machine learning calculation and dimensionless processing, fit to obtain the attenuation degree evaluation index Zpg of several groups of marked single cells, and take the attenuation degree evaluation index Zpg of the jth marked single cell as the value. j For example, it is obtained in the following way:

[0029] ；

[0030] Where, It is represented by the internal resistance of the jth marked single cell, It is expressed as the self-discharge rate of the jth marked single cell, Expressed as the polarization voltage value of the jth marked single cell, Expressed as the internal resistance safety value of a single battery, Expressed as the safety value of the self-discharge rate of a single battery, Expressed as the polarization voltage safety value of a single cell, where: 、 and Both are expressed as weight values, and A is expressed as a correction constant.

[0031] Preferably, the active balancing control module includes a control level determination unit and a balancing control execution unit;

[0032] The control level determination unit is used to set an evaluation threshold P for the decay degree evaluation index Zpg of the single cell, and compare and analyze the decay degree evaluation index Zpg of several groups of marked single cells with the preset evaluation threshold P. If the decay degree evaluation index Zpg is less than the preset evaluation threshold P, the corresponding marked single cell is considered to be in a normal decay state. Conversely, if the decay degree evaluation index Zpg is greater than or equal to the preset evaluation threshold P, the corresponding marked single cell is considered to be in an abnormal decay state, thereby triggering an active balancing control instruction.

[0033] The balancing control execution unit is used to receive and execute active balancing control instructions. The execution content of the active balancing control instruction is to use induction coil technology to transfer the electrical energy within each single cell of the marked single cell in an abnormal attenuation state, perform real-time balancing control, and continuously monitor relevant status information parameters of the marked single cells in the abnormal attenuation state until the status information parameters reach a relatively consistent level and the attenuation degree assessment index Zpg of each marked single cell in the abnormal attenuation state is less than an assessment threshold P. The relevant status information parameters include transient response voltage information data, battery self-discharge information data, and battery polarization voltage information data.

[0034] A battery pack intelligent balancing control method includes the following steps:

[0035] Step 1: Based on multiple sets of sensors deployed in the battery pack and combined with the transient current pulse method, the internal resistance information of each single battery in the battery pack is monitored to obtain transient response voltage information data;

[0036] Step 2: Analyze the transient response voltage information data to obtain the internal resistance Rdt of the corresponding single battery, mark the unhealthy single battery selected based on the internal resistance Rdt value of each single battery, and issue a battery degradation warning instruction;

[0037] Step 3: After receiving the battery degradation warning instruction, collect the self-discharge status information of the marked single cells in the stationary battery pack to obtain battery self-discharge information data, and collect battery polarization voltage information data based on the voltage change of the marked single cells from the initial charge and discharge stage to the stable stage. By analyzing the battery self-discharge information data and the battery polarization voltage information data and correlating them with the internal resistance Rdt of the marked single cells, the degradation degree evaluation index Zpg is obtained by fitting;

[0038] Step 4: Compare and analyze the attenuation evaluation index Zpg with the set evaluation threshold P to determine whether the attenuation degree of the marked single battery is normal, trigger the active balancing control instruction, and combine the induction coil balancing method to perform balancing control on the marked single battery in the battery pack with abnormal attenuation status.

[0039] A storage medium for intelligent balancing control of a battery pack stores a computer program, which, when executed by a processor, implements the functions of the intelligent balancing control system for a battery pack.

[0040] The present invention provides a battery pack intelligent balancing control method, system and storage medium, which have the following beneficial effects:

[0041] (1) Through precise monitoring and analysis, effective management and balancing of battery cells are achieved, and the overall performance and service life of the battery pack are improved. First, by using multiple sets of sensors and transient current pulse methods, the internal resistance information of each single cell can be obtained in real time, and the unhealthy single cells can be identified and marked in time through the internal resistance analysis screening module. This rapid response capability allows potential battery degradation problems to be warned at an early stage, avoiding safety hazards caused by unbalanced battery performance. In addition, the attenuation assessment module monitors the self-discharge state and polarization voltage information, and combines the marked single cell internal resistance Rdt to achieve a comprehensive assessment of the battery health status. The resulting attenuation degree assessment index Zpg can effectively guide subsequent balancing control decisions. The active balancing control module will identify the unhealthy battery after identifying the unhealthy battery. After the normal attenuation state, efficient energy transfer is achieved through induction coil technology, thereby adjusting the electrical energy from the high-voltage battery to the low-voltage battery. This dynamic adjustment not only reduces the performance difference between batteries, slows down the long-term power loss of abnormally attenuated single cells, which leads to accelerated battery aging, but also improves the overall energy utilization efficiency of the battery pack and extends the battery cycle life. At the same time, the intelligent design enables the battery pack to maintain a good condition during long-term operation, ensuring the stable power performance of electric vehicles and other applications. In addition, through real-time monitoring and feedback of data, the system can continuously optimize the balancing control strategy. This series of comprehensive measures enables the intelligent balancing control of the battery pack to show unique advantages and practical value in improving battery efficiency, extending service life and ensuring safety.

[0042] (2) The implementation of the single-cell monitoring module and the internal resistance analysis and screening module has improved the performance management of the battery pack. First, the multiple sets of sensors deployed have enabled the acquisition of the internal resistance characteristics of each single cell, especially the transient response analysis after applying a short-time current pulse, which can timely reflect the health status of the battery. Secondly, by applying Ohm's law to deeply analyze the transient response voltage data, the internal resistance Rdt of each single cell can be effectively calculated, and the mean value Rdt of the internal resistance of the single cell can be obtained by statistical methods. avg , which laid a scientific foundation for the subsequent screening of unhealthy single cells. Furthermore, by comparing the internal resistance Rdt of several groups of single cells with the average internal resistance Rdt of the single cells, avg By comparing the sizes, the system can quickly identify unhealthy single cells, mark them, and promptly issue battery degradation warning instructions. This active monitoring and warning mechanism improves the safety and reliability of the battery pack and reduces potential safety risks. In addition, the intelligent design and real-time feedback capabilities make battery management more efficient and provide accurate data support for subsequent balancing control.

[0043] (3) Through in-depth analysis of battery self-discharge information data and battery polarization voltage information data, combined with the marked single cell internal resistance Rdt, the calculation of the attenuation degree evaluation index Zpg realizes a comprehensive evaluation of the attenuation state of the single cell. This method comprehensively considers the influence of internal resistance increase, self-discharge rate increase and polarization voltage change factors, and uses machine learning and dimensionless processing to accurately identify the attenuation degree of the battery, and then effectively distinguish between normal and abnormal attenuation states. The design of the active balancing control module ensures that batteries in abnormal attenuation states can be balanced and adjusted in time, and the induction coil technology is used to achieve efficient transfer of electrical energy, thereby improving the overall performance and safety of the battery pack. This real-time monitoring and intelligent control capability not only extends the service life of the battery, but also improves the reliability and safety of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is a block diagram of a battery pack intelligent balancing control system of the present invention;

[0045] Figure 2 A schematic diagram of the steps of a battery pack intelligent balancing control method according to the present invention. DETAILED DESCRIPTION

[0046] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only 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 making creative efforts are within the scope of protection of the present invention.

[0047] Example 1

[0048] See also Figure 1 , the present invention provides a battery pack intelligent balancing control system, including a single battery monitoring module, an internal resistance analysis and screening module, an attenuation evaluation module and an active balancing control module;

[0049] The single cell monitoring module is based on multiple sets of sensors deployed in the battery pack and combines the transient current pulse method to monitor the internal resistance information of each single cell in the battery pack and obtain transient response voltage information data;

[0050] The internal resistance analysis and screening module is used to analyze the transient response voltage information data to obtain the internal resistance Rdt of the corresponding single battery, mark the unhealthy single battery screened out according to the internal resistance Rdt value of each single battery, and issue a battery degradation warning instruction;

[0051] The attenuation assessment module is configured to, upon receiving a battery attenuation warning instruction, collect self-discharge status information of marked single cells in a stationary battery pack to obtain battery self-discharge information data, and collect battery polarization voltage information data based on voltage changes of the marked single cells from the initial charge and discharge stage to the stable stage. The attenuation assessment index Zpg is obtained by fitting by analyzing the battery self-discharge information data and the battery polarization voltage information data and correlating them with the internal resistance Rdt of the marked single cells;

[0052] The active balancing control module is used to compare and analyze the attenuation evaluation index Zpg with the set evaluation threshold P to determine whether the attenuation degree of the marked single battery is normal, trigger the active balancing control instruction, and combine the induction coil balancing method to perform balancing control on the marked single battery in the battery pack with abnormal attenuation status.

[0053] This embodiment integrates single-cell monitoring, internal resistance analysis, degradation assessment, and active balancing control modules to achieve comprehensive monitoring and management of each single cell in the battery pack. First, by deploying multiple sets of sensors and combining them with transient current pulse methods, real-time battery internal resistance information and transient response voltage data are acquired, thereby identifying unhealthy single cells and issuing timely degradation warnings. This early warning mechanism can provide early warning and intervention, reducing the loss and failure risk caused by battery imbalance. Second, the degradation assessment module analyzes the self-discharge rate, polarization voltage, and single-cell internal resistance to quantify the battery degradation assessment index Zpg, enabling accurate judgment of the health status of the single cells. This precise assessment capability provides a reliable basis for subsequent balancing control, ensuring that the battery pack maintains good performance under different operating conditions. Finally, the active balancing control module uses induction coil technology to achieve efficient energy transfer, transferring electrical energy from high-voltage cells to low-voltage cells, reducing performance differences between cells and achieving balanced control of the battery pack. This dynamic adjustment and control not only improves the overall performance of the battery pack, but also extends the battery life, reduces replacement and maintenance costs, and enhances the safety and reliability of the battery pack.

[0054] Example 2

[0055] Please refer to Figure 1 ,Specifically: the single cell monitoring module includes a deployment unit and an internal resistance monitoring unit;

[0056] The deployment unit is used to install multiple sets of sensors between each single cell in the lithium-ion battery pack, including voltage sensors and current sensors;

[0057] The internal resistance monitoring unit is used to apply a short and known current pulse to each single cell, monitor the transient response voltage information of each single cell in the battery pack through the transient response of the single cell voltage, and obtain transient response voltage information data. The transient response voltage information data includes the pre-transient response voltage value Vqs and the post-steady-state drop voltage value Vhs of each single cell.

[0058] The pre-transient response voltage value Vqs refers to the voltage response of the single cell at the initial moment after a short and known current pulse is applied. The pre-transient response voltage value Vqs is used to evaluate the internal resistance characteristics of the battery, reflecting the transient behavior of the battery at the moment the pulse is applied, and is collected by high-precision voltage sensors installed at the positive and negative poles of the single cell.

[0059] The post-steady-state drop voltage value Vhs refers to the voltage value of the single cell when it reaches a steady state after a period of time after applying a short and known current pulse. The post-steady-state drop voltage value Vhs is used to calculate the internal resistance of the battery and is directly collected by a voltage sensor. The difference between the pre-transient response voltage value Vqs and the post-steady-state drop voltage value Vhs can be used to evaluate the internal resistance characteristics of the single cell, wherein the short time is at the millisecond level, specifically 1 millisecond.

[0060] Specifically, the internal resistance analysis and screening module includes an internal resistance analysis unit and a screening unit;

[0061] The internal resistance analysis unit is used to analyze the transient response voltage information data and calculate using Ohm's law to obtain the internal resistance Rdt of the corresponding single cell. i For example, it is obtained in the following way:

[0062] ;

[0063] Where, It is represented as the transient response voltage value of the ith single cell. It is expressed as the post-steady-state drop voltage value of the i-th single cell, Expressed as the current pulse value applied to each single cell;

[0064] According to the above, the internal resistance of the i-th single cell is obtained The internal resistance Rdt of several groups of single cells is obtained respectively, and the mean internal resistance Rdt of several groups of single cells is calculated based on the statistical mean value algorithm. avg ;

[0065] The screening unit is used to compare the internal resistance Rdt of several groups of single cells with the average internal resistance Rdt of the single cells. avg Compare the size and obtain the average internal resistance Rdt of the battery avg The internal resistance Rdt of the corresponding single battery is measured, and the corresponding unhealthy single batteries are screened out and marked, and a battery degradation warning instruction is issued.

[0066] In this embodiment, the intelligence and efficiency of battery management are improved by monitoring and analyzing the internal resistance of single cells. First, the multi-sensor configuration of the deployment unit, combined with high-precision voltage and current measurement, can monitor the voltage response of each single cell in real time, ensuring that the pre-transient response voltage value Vqs and the post-steady-state drop voltage value Vhs are obtained in a short time. This fast and efficient data acquisition enables the rapid identification of the internal resistance characteristics of the battery, providing a reliable foundation for subsequent health assessments. Secondly, the introduction of the internal resistance analysis and screening module accurately calculates the internal resistance Rdt of each single cell through Ohm's law, and uses statistical methods to calculate the mean internal resistance Rdt of the single cell. avg , which can systematically identify unhealthy single cells. This process not only improves the timeliness of fault detection, but also reduces the potential safety risks caused by uneven battery performance. At the same time, the screening unit can effectively issue battery degradation warning instructions to ensure the safety and stability of electric vehicles. Overall, the system's intelligent monitoring and analysis capabilities can provide real-time feedback on the health status of each single cell in the battery pack.

[0067] Example 3

[0068] Please refer to Figure 1 , specifically: the attenuation evaluation module includes an information acquisition unit, a self-discharge analysis unit, a polarization voltage analysis unit and an attenuation total evaluation unit;

[0069] The information acquisition unit is used to monitor the self-discharge status of marked single cells in the battery pack after a long period of rest in real time through multiple sets of sensors installed between the single cells in the lithium-ion battery pack after receiving the battery degradation warning instruction, and obtain battery self-discharge information data, wherein the battery self-discharge information data includes the voltage value of each marked single cell before rest. And the voltage value after static , and based on the voltage changes of the marked single cells from the initial stage of charge and discharge to the stable stage, collect battery polarization voltage information data, the battery polarization voltage information data includes the battery terminal instantaneous voltage value Vss and open circuit voltage value Vkk of each marked single cell.

[0070] The pre-rest voltage value Vqh refers to the voltage state of the single cell before resting, and is used to judge the charge state and health status of the single cell. It reflects the energy reserve level of the battery before resting, and is monitored and collected in real time by high-precision voltage sensors installed at the positive and negative electrodes of the single cell.

[0071] The post-rest voltage value Vhh refers to the voltage value of the single cell after a certain rest period, and is used to analyze the self-discharge characteristics of the single cell. Data is collected by a voltage sensor after the rest period.

[0072] The battery terminal instantaneous voltage value Vss refers to the instantaneous voltage at the single cell terminal during the charge and discharge process, which is used to evaluate the dynamic performance and load characteristics of the battery and is collected by high-frequency voltage sensors installed at the positive and negative electrodes of the single cell.

[0073] The open circuit voltage value Vkk refers to the voltage across a single cell when the battery is not under load and is not charging or discharging. It reflects the actual voltage state and electrochemical potential of the single cell and is an important indicator of the battery's health. The open circuit voltage is related to the battery's charge and discharge state and health. The difference between the open circuit voltage and the instantaneous voltage at the battery end reflects the polarization of the battery. It is collected by a voltage sensor when the battery is not connected to a load.

[0074] In this embodiment, after receiving the battery degradation warning instruction, multiple sets of sensors are used to monitor the self-discharge status of marked single cells in the lithium-ion battery pack in real time, thereby improving the accuracy and response speed of battery management. By collecting the voltage values ​​before and after static and the battery polarization voltage information, the self-discharge behavior and polarization state of the battery under static conditions can be evaluated. This detailed monitoring enables the battery management system to quickly identify potential performance degradation, provide data support for subsequent timely adjustment of maintenance strategies, and reduce battery safety risks. In addition, by analyzing the voltage changes of the battery from the initial charging and discharging stage to the stable stage, a scientific basis is provided for subsequent balancing control, thereby achieving optimized management of the battery pack and extending its service life. In summary, the information acquisition unit provides a more intelligent and efficient monitoring method.

[0075] Example 4

[0076] Please refer to Figure 1 Specifically: the self-discharge analysis unit is used to analyze the obtained battery self-discharge information data, obtain the self-discharge rate Dfd of several groups of marked single cells, and use the self-discharge rate Dfd of the jth marked single cell as the value. j For example, it is obtained in the following way:

[0077] ;

[0078] Where, It is represented by the voltage value of the jth marked single cell before standing, It is represented by the voltage value of the jth marked single cell after standing, Indicates the length of time it takes to rest.

[0079] Specifically, the polarization voltage analysis unit is used to analyze the obtained battery polarization voltage information data, obtain the polarization voltage values ​​Vjh of several groups of marked single cells, and use the polarization voltage value Vjh of the jth marked single cell as the value. jFor example, it is obtained in the following way:

[0080] ;

[0081] Where, It is represented by the instantaneous voltage value of the battery terminal of the jth marked single cell. It is expressed as the open circuit voltage value of the jth marked single cell.

[0082] In this embodiment, the combined application of the self-discharge analysis unit and the polarization voltage analysis unit enhances the health assessment capability of the battery pack. By calculating the self-discharge rate Dfd and polarization voltage value Vjh of the marked single cells, the battery performance degradation can be quickly identified. The accurate measurement of the self-discharge rate helps the management system to evaluate the battery's energy loss in real time and promptly discover potential safety hazards. The monitoring of the polarization voltage provides key data for evaluating the electrochemical reaction state inside the battery. The real-time acquisition and analysis of this information enables the battery management system to adopt a more scientific maintenance strategy, optimize the charging and discharging process, and thereby extend the battery's service life and improve overall safety.

[0083] Example 5

[0084] Please refer to Figure 1 Specifically: the total attenuation evaluation unit is used to analyze the battery self-discharge information data and battery polarization voltage information data, and associate them with the marked single cell internal resistance Rdt, and after machine learning calculation and dimensionless processing, fit to obtain the attenuation degree evaluation index Zpg of several groups of marked single cells, and use the attenuation degree evaluation index Zpg of the jth marked single cell as the value. For example, it is obtained in the following way:

[0085] ；

[0086] Where, It is represented by the internal resistance of the jth marked single cell, It is expressed as the self-discharge rate of the jth marked single cell, Expressed as the polarization voltage value of the jth marked single cell, Expressed as the internal resistance safety value of a single battery, Expressed as the safety value of the self-discharge rate of a single battery, Expressed as the polarization voltage safety value of a single cell, where: 、 and Both are expressed as weight values, and A is expressed as a correction constant.

[0087] It should be noted that the internal resistance safety value, self-discharge rate safety value and polarization voltage safety value of the single battery are set by referring to industry standards and the recommended values ​​provided by the manufacturer, combined with actual test results.

[0088] Specifically, the active balancing control module includes a control level determination unit and a balancing control execution unit;

[0089] The control level determination unit is used to set an evaluation threshold P for the decay degree evaluation index Zpg of the single cell, and compare and analyze the decay degree evaluation index Zpg of several groups of marked single cells with the preset evaluation threshold P. If the decay degree evaluation index Zpg is less than the preset evaluation threshold P, the corresponding marked single cell is considered to be in a normal decay state. Conversely, if the decay degree evaluation index Zpg is greater than or equal to the preset evaluation threshold P, the corresponding marked single cell is considered to be in an abnormal decay state, thereby triggering an active balancing control instruction.

[0090] The balancing control execution unit is used to receive and execute active balancing control instructions. The execution content of the active balancing control instruction is to use induction coil technology to transfer the electrical energy within each single cell of the marked single cell in an abnormal attenuation state, perform real-time balancing control, and continuously monitor relevant status information parameters of the marked single cells in the abnormal attenuation state until the status information parameters reach a relatively consistent level and the attenuation degree assessment index Zpg of each marked single cell in the abnormal attenuation state is less than an assessment threshold P. The relevant status information parameters include transient response voltage information data, battery self-discharge information data, and battery polarization voltage information data.

[0091] It should be noted that the induction coil technology is a method of transmitting energy between single cells using the principle of electromagnetic induction. By using induction coil technology for marked single cells in abnormal attenuation states, the energy loss of single cells that do not require balancing control is reduced. In actual applications, by deploying induction coils between single cells, when the system detects marked single cells in abnormal attenuation states, it adjusts the energy output of the high-voltage battery, starts the induction coil, generates an alternating electromagnetic field, and helps charge the low-voltage battery. This process realizes the contactless transfer of electrical energy. During the entire process, relevant status information parameters such as transient response voltage, self-discharge rate and polarization voltage are monitored in real time to ensure that battery performance is consistent and to improve the efficiency and safety of the overall battery pack.

[0092] In this embodiment, the integration of the overall attenuation assessment unit and the active balancing control module enhances the intelligent management and performance optimization capabilities of the battery pack. Through in-depth analysis of self-discharge and polarization voltage data, combined with the internal resistance Rdt of labeled individual cells, the degradation level of each individual cell can be accurately assessed, generating a degradation level assessment index Zpg. This method, based on machine learning and dimensionless processing, ensures real-time monitoring and accurate identification of the attenuation state, promptly triggering active balancing control instructions. Efficient energy transfer is achieved through induction coil technology, thereby regulating electrical energy from high-voltage cells to low-voltage cells. This dynamic regulation not only reduces performance differences between cells and mitigates the long-term power loss of abnormally attenuated cells, which leads to accelerated battery aging, but also improves the overall energy utilization efficiency of the battery pack and extends the battery's cycle life. Furthermore, this dynamic regulation and control enables the battery pack to maintain good condition during long-term operation, ensuring stable power performance in electric vehicles and other applications, improving the overall performance of the battery pack, extending the battery life, and reducing replacement and maintenance costs.

[0093] Example 6

[0094] Please refer to Figure 1 and Figure 2 ,Specifically: A battery pack intelligent balancing control method, comprising the following steps;

[0095] Step 1: Based on multiple sets of sensors deployed in the battery pack and combined with the transient current pulse method, the internal resistance information of each single battery in the battery pack is monitored to obtain transient response voltage information data;

[0096] Step 2: Analyze the transient response voltage information data to obtain the internal resistance Rdt of the corresponding single battery, mark the unhealthy single battery selected based on the internal resistance Rdt value of each single battery, and issue a battery degradation warning instruction;

[0097] Step 3: After receiving the battery degradation warning instruction, collect the self-discharge status information of the marked single cells in the stationary battery pack to obtain battery self-discharge information data, and collect battery polarization voltage information data based on the voltage change of the marked single cells from the initial charge and discharge stage to the stable stage. By analyzing the battery self-discharge information data and the battery polarization voltage information data and correlating them with the internal resistance Rdt of the marked single cells, the degradation degree evaluation index Zpg is obtained by fitting;

[0098] Step 4: Compare and analyze the attenuation evaluation index Zpg with the set evaluation threshold P to determine whether the attenuation degree of the marked single battery is normal, trigger the active balancing control instruction, and combine the induction coil balancing method to perform balancing control on the marked single battery in the battery pack with abnormal attenuation status.

[0099] A storage medium for intelligent balancing control of a battery pack stores a computer program, which, when executed by a processor, implements the functions of the intelligent balancing control system for a battery pack.

[0100] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A battery pack intelligent balancing control system, characterized by: It includes single cell monitoring module, internal resistance analysis and screening module, attenuation evaluation module and active balancing control module; The single cell monitoring module is based on multiple sets of sensors deployed in the battery pack and combines the transient current pulse method to monitor the internal resistance information of each single cell in the battery pack and obtain transient response voltage information data; The internal resistance analysis and screening module is used to analyze the transient response voltage information data to obtain the internal resistance Rdt of the corresponding single battery, mark the unhealthy single battery screened out according to the internal resistance Rdt value of each single battery, and issue a battery degradation warning instruction; The attenuation assessment module is configured to, upon receiving a battery attenuation warning instruction, collect self-discharge status information of marked single cells in a stationary battery pack to obtain battery self-discharge information data, and collect battery polarization voltage information data based on voltage changes of the marked single cells from the initial charge and discharge stage to the stable stage. The attenuation assessment index Zpg is obtained by fitting by analyzing the battery self-discharge information data and the battery polarization voltage information data and correlating them with the internal resistance Rdt of the marked single cells; The active balancing control module is used to compare and analyze the attenuation evaluation index Zpg with the set evaluation threshold P to determine whether the attenuation of the marked single battery is normal, trigger the active balancing control instruction, and combine the induction coil balancing method to perform balancing control on the marked single battery in the battery pack with abnormal attenuation status; The active balancing control module includes a control level determination unit and a balancing control execution unit; The control level determination unit is used to set an evaluation threshold P for the decay degree evaluation index Zpg of the single cell, and compare and analyze the decay degree evaluation index Zpg of several groups of marked single cells with the preset evaluation threshold P. If the decay degree evaluation index Zpg is less than the preset evaluation threshold P, the corresponding marked single cell is considered to be in a normal decay state. Conversely, if the decay degree evaluation index Zpg is greater than or equal to the preset evaluation threshold P, the corresponding marked single cell is considered to be in an abnormal decay state, thereby triggering an active balancing control instruction. The balancing control execution unit is used to receive and execute active balancing control instructions. The execution content of the active balancing control instruction is to use induction coil technology to transfer the electrical energy within each single cell of the marked single cell in an abnormal attenuation state, perform real-time balancing control, and continuously monitor relevant status information parameters of the marked single cells in the abnormal attenuation state until the status information parameters reach a relatively consistent level and the attenuation degree assessment index Zpg of each marked single cell in the abnormal attenuation state is less than an assessment threshold P. The relevant status information parameters include transient response voltage information data, battery self-discharge information data, and battery polarization voltage information data.

2. The battery pack intelligent balancing control system according to claim 1, characterized in that: The single cell monitoring module includes a deployment unit and an internal resistance monitoring unit; The deployment unit is used to install multiple sets of sensors between each single cell in the lithium-ion battery pack, including voltage sensors and current sensors; The internal resistance monitoring unit is used to apply a short and known current pulse to each single cell, monitor the transient response voltage information of each single cell in the battery pack through the transient response of the single cell voltage, and obtain transient response voltage information data. The transient response voltage information data includes the pre-transient response voltage value Vqs and the post-steady-state drop voltage value Vhs of each single cell.

3. The battery pack intelligent balancing control system according to claim 2, characterized in that: The internal resistance analysis and screening module includes an internal resistance analysis unit and a screening unit; The internal resistance analysis unit is used to analyze the transient response voltage information data and calculate using Ohm's law to obtain the internal resistance Rdt of the corresponding single cell. i For example, it is obtained in the following way: Where Vqs i Expressed as the pre-transient response voltage value of the i-th single cell, Vhs i It is represented by the post-steady-state drop voltage value of the i-th single cell, and ΔI is represented by the current pulse value applied to each single cell; According to the above, the internal resistance Rdt of the i-th single cell is obtained i The internal resistance Rdt of several groups of single cells is obtained respectively, and the mean internal resistance Rdt of several groups of single cells is calculated based on the statistical mean value algorithm. avg ; The screening unit is used to compare the internal resistance Rdt of several groups of single cells with the average internal resistance Rdt of the single cells. avg Compare the size and obtain the average internal resistance Rdt of the battery avg The internal resistance Rdt of the corresponding single battery is measured, and the corresponding unhealthy single batteries are screened out and marked, and a battery degradation warning instruction is issued.

4. The battery pack intelligent balancing control system according to claim 3, characterized in that: The attenuation assessment module includes an information acquisition unit, a self-discharge analysis unit, a polarization voltage analysis unit and an overall attenuation assessment unit; The information acquisition unit is used to, after receiving a battery degradation warning instruction, monitor the self-discharge status of marked single cells in the battery pack that have been stationary for a long time in real time through multiple sets of sensors installed between each single cell in the lithium-ion battery pack, and obtain battery self-discharge information data. The battery self-discharge information data includes the pre-stationary voltage value Vqh and the post-stationary voltage value Vhh of each marked single cell. In addition, based on the voltage change of the marked single cell from the initial stage of charge and discharge to the stable stage, the battery polarization voltage information data is collected. The battery polarization voltage information data includes the battery terminal instantaneous voltage value Vss and the open circuit voltage value Vkk of each marked single cell.

5. The battery pack intelligent balancing control system according to claim 4, characterized in that: The self-discharge analysis unit is used to analyze the obtained battery self-discharge information data, obtain the self-discharge rate Dfd of several groups of marked single cells, and use the self-discharge rate Dfd of the jth marked single cell as the value. j For example, it is obtained in the following way: Where Vqh j It is represented by the voltage value before the jth marked single cell is placed in the static state, Vhh j It is represented by the voltage value of the jth marked single cell after standing, and Δt is represented by the standing time.

6. The battery pack intelligent balancing control system according to claim 4, characterized in that: The polarization voltage analysis unit is used to analyze the obtained battery polarization voltage information data, obtain the polarization voltage values ​​Vjh of several groups of marked single cells, and use the polarization voltage value Vjh of the jth marked single cell as the value. j For example, it is obtained in the following way: Vjh j =Vss j -Vkk j , Where Vss j It is represented by the instantaneous voltage value of the battery terminal of the jth marked single cell, Vkk j It is expressed as the open circuit voltage value of the jth marked single cell.

7. The battery pack intelligent balancing control system according to claim 4, characterized in that: The total attenuation evaluation unit is used to analyze the battery self-discharge information data and battery polarization voltage information data, and associate them with the marked single cell internal resistance Rdt, and after machine learning calculation and dimensionless processing, fit to obtain the attenuation degree evaluation index Zpg of several groups of marked single cells, and take the attenuation degree evaluation index Zpg of the jth marked single cell as the value. j For example, it is obtained in the following way: In the formula, Rdt j Expressed as the internal resistance of the jth marked single cell, Dfd j Expressed as the self-discharge rate of the jth marked single cell, Vjh j Expressed as the polarization voltage value of the jth marked single cell, Rdt Max Expressed as the internal resistance safety value of a single battery, Dfd Max Expressed as the safety value of the self-discharge rate of a single battery, Vjh Max It is expressed as the polarization voltage safety value of a single cell, where α, β and γ are all weight values, and A is a correction constant.

8. A battery pack intelligent balancing control method, characterized in that: The method is applied to a battery pack intelligent balancing control system according to any one of claims 1 to 7, comprising the following steps: Step 1: Based on multiple sets of sensors deployed in the battery pack and combined with the transient current pulse method, the internal resistance information of each single battery in the battery pack is monitored to obtain transient response voltage information data; Step 2: Analyze the transient response voltage information data to obtain the internal resistance Rdt of the corresponding single battery, mark the unhealthy single battery selected based on the internal resistance Rdt value of each single battery, and issue a battery degradation warning instruction; Step 3: After receiving the battery degradation warning instruction, collect the self-discharge status information of the marked single cells in the stationary battery pack to obtain battery self-discharge information data, and collect battery polarization voltage information data based on the voltage change of the marked single cells from the initial charge and discharge stage to the stable stage. By analyzing the battery self-discharge information data and the battery polarization voltage information data and correlating them with the internal resistance Rdt of the marked single cells, the degradation degree evaluation index Zpg is obtained by fitting; Step 4: Compare and analyze the attenuation evaluation index Zpg with the set evaluation threshold P to determine whether the attenuation degree of the marked single battery is normal, trigger the active balancing control instruction, and combine the induction coil balancing method to perform balancing control on the marked single battery in the battery pack with abnormal attenuation status.

9. A storage medium for intelligent balancing control of a battery pack, on which a computer program is stored, characterized in that: When the program is executed by a processor, the functions of a battery pack intelligent balancing control system as described in any one of claims 1 to 7 are realized.

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