Storage battery dynamic balance management method and device, storage medium and electronic equipment

Abstract

The invention relates to a storage battery dynamic balance management method and device, a storage medium and electronic equipment. The balance efficiency and the balance precision of storage battery dynamic balance management can be improved. The method comprises: determining a first difference value between a working parameter of each single battery in a storage battery pack and an average working parameter of the storage battery pack, the average working parameter of the storage battery pack being an average value of the working parameters of each single battery in the storage battery; under the condition that the absolute value of the first difference value is greater than a first threshold value, performing dynamic balance management on the storage battery pack based on a constant current control strategy; and under the condition that the absolute value of the first difference value is greater than a second threshold value and less than the first threshold value, carrying out dynamic balance management on the storage battery pack based on a constant voltage control strategy.

Description

Technical Field

[0001] The present disclosure relates to the technical field of storage batteries, and in particular to a method, device, storage medium and electronic device for dynamic balancing management of storage batteries. Background Art

[0002] With the development of renewable energy and the construction of smart grids, batteries have been widely used as energy storage devices. Since the capacity of a single battery is usually limited and cannot meet the energy requirements of high-power equipment or long-term operation systems, by combining multiple batteries into a battery pack, the total capacity can be significantly increased, thereby providing more energy.

[0003] However, in actual use, due to differences between individual batteries and different usage environments, the capacity, voltage and other parameters of each single cell in the battery pack will be inconsistent. This inconsistency will accelerate the aging process of the entire battery pack, shorten its service life, and may even cause safety problems. For example, voltage inconsistency may cause some single cells to be overcharged or over-discharged. Overcharging will increase the internal pressure of the battery, which may cause safety problems such as battery expansion and rupture; over-discharging will damage the internal structure of the battery, reduce the performance and life of the battery, and may even cause the battery to be unable to be recharged.

[0004] In the related art, the existing battery balancing management method has problems such as low balancing efficiency and poor balancing accuracy. Summary of the invention

[0005] The purpose of the present disclosure is to provide a method, device, storage medium and electronic device for dynamic balancing management of batteries, which can improve the balancing efficiency and balancing accuracy of dynamic balancing management of batteries.

[0006] In order to achieve the above objectives, in a first aspect, the present disclosure provides a method for dynamic equalization management of a battery, the method comprising: Determine a first difference between an operating parameter of each single cell in the battery pack and an average operating parameter of the battery pack, wherein the average operating parameter of the battery pack is an average value of the operating parameter of each single cell in the battery; When the absolute value of the first difference is greater than a first threshold, dynamically balancing the battery pack based on a constant current control strategy; When the absolute value of the first difference is greater than the second threshold and less than the first threshold, dynamic balancing management is performed on the battery pack based on a constant voltage control strategy.

[0007] Optionally, determining a first difference between an operating parameter of each single cell in the battery pack and an average operating parameter of the battery pack includes: When the usage time of the storage battery pack is less than or equal to the first time time, determining the difference between the voltage of each single cell and the average voltage of the storage battery pack as the first difference; When the usage time of the storage battery pack is greater than the first time, the difference between the power of each single cell and the average power of the storage battery pack is determined as the first difference.

[0008] Optionally, the method further comprises: Obtaining the real-time temperature and load change rate of the battery pack; A first proportional parameter is determined according to the real-time temperature and the load change rate, wherein the real-time temperature and the load change rate are both proportional to the first proportional parameter.

[0009] Optionally, determining a first proportional parameter according to the real-time temperature and the load change rate includes: Determining a second proportional parameter according to the real-time temperature; Determining a third proportional parameter according to the load change rate; The first proportion parameter is obtained by weighted summing the second proportion parameter and the third proportion parameter.

[0010] Optionally, the method further comprises: Obtaining the chemical composition, capacity level and charge and discharge frequency of the battery pack; determining the second threshold value according to the chemical composition, the capacity level and the charge and discharge frequency; The product of the first ratio parameter and the second threshold is determined as the first threshold.

[0011] Optionally, the dynamic balancing management of the battery pack based on the constant current control strategy includes: Determine a plurality of first single cells and a plurality of second single cells according to the first difference corresponding to each single cell, wherein the first single cell is a single cell whose corresponding first difference is greater than the second threshold, and the second single cell is a single cell whose corresponding first difference is less than 0 and whose absolute value of the first difference is greater than the second threshold; In the case where the preference information input by the user is the first preference information, according to the power value corresponding to each single cell, the single cell with the largest power value among the plurality of the first single cells is determined as the third single cell, and the single cell with the smallest power value among the plurality of the second single cells is determined as the fourth single cell; In the case where the preference information input by the user is the second preference information, according to the internal resistance value corresponding to each single cell, the single cell with the smallest internal resistance value among the plurality of the first single cells is determined as the third single cell, and the single cell with the largest internal resistance value among the plurality of the second single cells is determined as the fourth single cell; Transferring the energy of the third single cell to the fourth single cell, and when the absolute value of the first difference corresponding to any single cell is less than or equal to the second threshold, updating the first difference corresponding to the current third single cell and the current fourth single cell respectively; According to the updated first difference, return to the step of determining a plurality of first single cells and a plurality of second single cells according to the first difference corresponding to each single cell, until the absolute value of the first difference corresponding to each single cell is less than or equal to the second threshold.

[0012] Optionally, transferring the energy of the third single cell to the fourth single cell comprises: During a first preset period of time, the energy storage element is charged through the third single battery, and during a second preset period of time, the fourth single battery is charged through the energy storage element.

[0013] In a second aspect, the present disclosure provides a battery dynamic balancing management device, the device comprising: A determination module, configured to determine a first difference between an operating parameter of each single cell in a storage battery pack and an average operating parameter of the storage battery pack, wherein the average operating parameter of the storage battery pack is an average value of the operating parameters of each single cell in the storage battery; A first balancing management module, configured to perform dynamic balancing management on the battery pack based on a constant current control strategy when an absolute value of the first difference is greater than a first threshold; The second balancing management module is used to perform dynamic balancing management on the battery group based on a constant voltage control strategy when the absolute value of the first difference is greater than a second threshold and less than the first threshold.

[0014] In a third aspect, the present disclosure further provides a non-temporary computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of any one of the methods described in the first aspect.

[0015] In a fourth aspect, the present disclosure further provides an electronic device, including: a memory having a computer program stored thereon; A processor is used to execute the computer program in the memory to implement the steps of any one of the methods in the first aspect.

[0016] Through the above technical solution, the first difference between the working parameters of each single cell in the battery pack and the average working parameters of the battery pack is determined, and when the absolute value of the first difference is greater than the first threshold, the battery pack is dynamically balanced based on the constant current control strategy. When the absolute value of the first difference is greater than the second threshold and less than the first threshold, the battery pack is dynamically balanced based on the constant voltage control strategy. Among them, by real-time monitoring of the difference between the working parameters of the single cell and the average working parameters of the battery pack, and adopting corresponding balancing management strategies, the inconsistency between the single cells can be effectively reduced, the overall performance of the battery pack can be improved, and the balancing efficiency and balancing accuracy of the dynamic balancing management of the battery can be improved.

[0017] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings: Figure 1 The figure is a flow chart of a method for dynamic balancing management of a battery according to an exemplary embodiment of the present disclosure.

[0019] Figure 2 The figure is a block diagram of a battery dynamic balancing management device according to an exemplary embodiment of the present disclosure.

[0020] Figure 3 is a block diagram of an electronic device according to an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION

[0021] The specific implementation of the present disclosure is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the present disclosure, and is not used to limit the present disclosure.

[0022] As mentioned in the background art, in the related art, the existing battery balancing management method has problems such as low balancing efficiency and poor balancing accuracy.

[0023] In view of this, the embodiments of the present disclosure provide a method, device, storage medium and electronic device for dynamic balancing management of batteries, which can improve the balancing efficiency and balancing accuracy of dynamic balancing management of batteries.

[0024] Figure 1 is a flow chart of a method for dynamic equalization management of a battery according to an exemplary embodiment of the present disclosure. Figure 1 As shown, the method may include the following steps: Step S101 , determining a first difference between an operating parameter of each single cell in a battery pack and an average operating parameter of the battery pack, wherein the average operating parameter of the battery pack is an average value of the operating parameters of each single cell in the battery.

[0025] It should be understood that, in the present embodiment, the operating parameters of the single cell may be parameters such as voltage and charge that reflect the battery status, and the average operating parameter of the battery pack may be the average voltage or average charge of the battery pack. The average voltage of the battery pack may be obtained by calculating the average value of the voltages of each single cell in the battery, and the average charge of the battery pack may be obtained by calculating the average value of the charge of each single cell in the battery.

[0026] It should also be understood that by calculating the difference between the operating parameters of each single cell and the average operating parameters of the battery pack, a first difference can be obtained, which can be used to characterize the degree of deviation of each single cell from the average state of the entire battery pack.

[0027] Step S102 : When the absolute value of the first difference is greater than a first threshold, dynamic balancing management is performed on the battery pack based on a constant current control strategy.

[0028] It should be understood that in this embodiment, when the first difference between the voltage of a single cell and the average voltage of the battery group is greater than 0, or the first difference between the power of a single cell and the average power of the battery group is greater than 0, it indicates that the single cell is in an overcharged state relative to other single cells, and the single cell can be called a high-power single cell. When the first difference between the voltage of a single cell and the average voltage of the battery group is less than 0, or the first difference between the power of a single cell and the average power of the battery group is less than 0, it indicates that the charging speed of the single cell is slow or its charging acceptance capacity is weak, resulting in the single cell not being fully charged, and the single cell can be called a low-power single cell. The above situations all indicate that the battery group is in an unbalanced state and requires balancing management.

[0029] Specifically, considering a certain error range, this embodiment sets a first threshold value. If the absolute value of the first difference corresponding to a single cell is greater than the first threshold value, it means that the single cell is significantly different from the average state, and a constant current control strategy can be used for dynamic balancing management. The constant current control strategy continuously transfers the energy of a high-power cell to a low-power cell with a fixed current, or consumes the excess energy of a high-power cell, which can increase the balancing speed. At the same time, since the current is constant, the time required for balancing can be predicted based on the capacity of the single cell and the size of the first difference, so as to better plan the balancing process.

[0030] Step S103 , when the absolute value of the first difference is greater than the second threshold value and less than the first threshold value, dynamic balancing management is performed on the battery pack based on the constant voltage control strategy.

[0031] It should be understood that in this embodiment, when the absolute value of the first difference is between the second threshold and the first threshold, it indicates that the difference between the operating parameters of the single cell and the average operating parameters of the battery pack is small, and at this time, a constant voltage control strategy can be used for dynamic balancing management. The constant voltage control strategy can more accurately maintain the stability of the single cell voltage. During the charging process, if the voltage of a single cell approaches the set constant voltage upper limit, the charging current will be reduced or the charging will be stopped to prevent overcharging; during the discharging process, if the voltage of a single cell approaches the set constant voltage lower limit, the discharge current will be reduced or the discharge will be stopped to prevent over-discharge. The constant voltage control strategy can improve the accuracy of balancing, thereby improving the overall performance and life of the battery pack.

[0032] For example, the first threshold is 15V, the second threshold is 10V, and the first difference between the voltage of the single cell A and the average voltage of the battery pack is 30V. Since the first difference is greater than the second threshold, it is necessary to adopt a constant voltage control strategy for dynamic balancing management to transfer the power of the single cell A to the single cell with low power. As the dynamic balancing management proceeds, the voltage of the single cell A gradually decreases, and the first difference gradually decreases. When the first difference decreases to below 15V, the constant voltage control strategy can be used for dynamic balancing management to more accurately maintain the stability of the single cell voltage.

[0033] The first threshold and the second threshold are both preset constants, and the first threshold is greater than the second threshold. Those skilled in the art can flexibly design the specific values ​​of the first threshold and the second threshold according to actual needs. For example, for situations where the balancing accuracy is high, a smaller first threshold and a larger second threshold can be set to adjust the unbalanced state of the battery pack in time; for situations where the balancing accuracy is not high, a larger first threshold and a smaller second threshold can be set to reduce the amount of calculation.

[0034] Through the above-mentioned method, this embodiment can effectively reduce the inconsistency between the single cells and the average working parameters of the battery pack by real-time monitoring the difference between the working parameters of the single cell and the average working parameters of the battery pack, and adopt corresponding balancing management strategies, so as to improve the overall performance of the battery pack. At the same time, when the working parameters of the single cell differ greatly from the average working parameters of the battery pack, the constant current control strategy is adopted for dynamic balancing management, which can quickly adjust the working parameters of the single cell, thereby realizing rapid balancing of the battery pack; when the working parameters of the single cell differ little from the average working parameters of the battery pack, the constant voltage control strategy is adopted for dynamic balancing management, which can more accurately maintain the voltage stability of the single cell and improve the balancing accuracy.

[0035] In a possible implementation, determining a first difference between an operating parameter of each single cell in the battery pack and an average operating parameter of the battery pack may include: When the usage time of the storage battery group is less than or equal to the first time, determining the difference between the voltage of each single cell and the average voltage of the storage battery group as the first difference; When the usage time of the storage battery pack is greater than the first time, the difference between the power of each single cell and the average power of the storage battery pack is determined as the first difference.

[0036] It should be understood that, in this embodiment, the usage time refers to the length of time from the start of the battery pack being put into use to the current moment, and can also be understood as the cumulative operating time of the battery pack. In the early stage of the use of the battery pack (that is, when the usage time of the battery pack is less than or equal to the first time), the power state of the single battery is relatively consistent, and the voltage fluctuation is relatively obvious, which is conducive to quickly judging the difference between the single battery and the whole. At the same time, voltage is a parameter that is relatively easy to measure, which can quickly reflect the overall state of the battery pack. By monitoring the voltage difference, it can be quickly determined whether the battery pack is in a balanced state. Too high or too low voltage can cause safety problems such as battery overheating, fire, and even explosion. Therefore, by monitoring the voltage difference, abnormal single batteries can be discovered in time and corresponding safety measures can be taken.

[0037] It should also be understood that the power level can reflect the total amount of energy that the battery can store and release. As the usage time increases, the battery capacity may change due to factors such as aging and self-discharge. Therefore, when the battery pack is used for a long time (i.e., longer than the first time), by comparing the power level differences, it is possible to more accurately determine which single cells need to be equalized to ensure the performance and life of the entire battery pack.

[0038] In the above manner, this embodiment selects appropriate working parameters to calculate the first difference according to different use stages, so that the equalization management can be performed more targeted. In the early stage of use, by paying attention to the voltage difference, the problem of unbalanced voltage of single cells caused by manufacturing differences, poor connection, etc. can be discovered and solved in time to avoid further deterioration of the problem. In the later stage of use, the equalization requirements caused by battery aging, capacity attenuation, etc. can be better responded to based on the power difference, thereby improving the overall performance and service life of the battery pack.

[0039] In a possible implementation, the method may further include: Get the real-time temperature and load change rate of the battery pack; A first proportional parameter is determined according to the real-time temperature and the load change rate, wherein the real-time temperature and the load change rate are both proportional to the first proportional parameter.

[0040] It should be understood that in this embodiment, considering that the charge and discharge characteristics, internal resistance, capacity, etc. of the battery will change at different temperatures, the battery may experience a decrease in capacity, an increase in internal resistance, and a more unstable voltage change in a high temperature environment. Therefore, in a high temperature environment, the first proportional parameter can be set relatively large, and then a larger first threshold can be set, so as to switch the balancing strategy to a constant voltage control strategy in time to ensure the voltage stability of the single cell. In a low temperature environment, the charge and discharge capacity of the battery may decrease, but the voltage change is relatively stable. The first proportional parameter can be set relatively small, and then a smaller first threshold can be set to increase the action time of the constant current control strategy and improve the balancing speed.

[0041] At the same time, considering that load changes will affect the output current and voltage of the battery pack, if the load change rate of the battery pack is large (the load change rate refers to the degree of change of the load per unit time), for example, in a device that is frequently started and stopped, the voltage fluctuation of the battery pack is large, therefore, the first proportional parameter can be set larger to switch the balancing strategy to the constant voltage control strategy in time to ensure the voltage stability of the single battery.

[0042] In a possible implementation, determining the first proportional parameter according to the real-time temperature and the load change rate may include: Determine a second proportional parameter according to the real-time temperature; Determining a third proportional parameter according to the load change rate; The second proportional parameter and the third proportional parameter are weighted and summed to obtain the first proportional parameter.

[0043] It should be understood that, in this embodiment, when determining the second proportional parameter based on the real-time temperature of the battery pack, a reference value of the second proportional parameter may be preset. , a first temperature threshold and a second temperature threshold, when the real-time temperature of the battery pack is between the first temperature threshold and the second temperature threshold, the second proportional parameter is equal to the reference value When the real-time temperature of the battery pack is less than the first temperature threshold, the second proportional parameter is at the reference value It decreases linearly based on .

[0044] For example, the second ratio parameter can be calculated by the following calculation formula (1): (1) in, is the second scale parameter, is the reference value of the second scale parameter, is the first temperature threshold, is a preset constant, and T is the real-time temperature of the battery pack.

[0045] When the temperature of the battery pack is greater than the second temperature threshold, the second proportional parameter increases linearly based on the reference value. For example, the second proportional parameter can be calculated by the following calculation formula (2): (2) in, is the second scale parameter, is the reference value of the second scale parameter, is the second temperature threshold, is a preset constant, and T is the real-time temperature of the battery pack.

[0046] Similarly, when determining the third proportional parameter based on the load change rate, the reference value of the third proportional parameter can be preset. , a first change threshold and a second change threshold, when the load change rate of the battery pack is between the first change threshold and the second change threshold, the third proportional parameter is equal to the reference value When the load change rate of the battery pack is less than the first change threshold, the third proportional parameter is at the reference value It decreases linearly based on .

[0047] For example, the third ratio parameter can be calculated by the following calculation formula (3): (3) in, is the third scale parameter, is the reference value of the third proportional parameter, is the first change threshold, is a preset constant, and c is the load change rate of the battery pack.

[0048] When the load change rate of the battery pack is greater than the second change threshold, the third proportional parameter increases linearly based on the reference value. For example, the second proportional parameter can be calculated by the following calculation formula (4): (4) in, is the third scale parameter, is the reference value of the third proportional parameter, represents the second change threshold, is a preset constant, and c is the load change rate of the battery pack.

[0049] Therefore, on the basis of obtaining the second proportional parameter and the third proportional parameter, the second proportional parameter and the third proportional parameter are weighted and summed to obtain the first proportional parameter.

[0050] In the above manner, this embodiment determines the first proportional parameter based on different temperatures and load change rates, which is conducive to reasonably allocating the action time of the constant current control strategy and the constant voltage control strategy, thereby improving the balancing effect of the battery pack.

[0051] In a possible implementation, the method may further include: Obtain the chemical composition, capacity level, and charge and discharge frequency of the battery pack; Determining a second threshold value according to the chemical composition, capacity level, and charge and discharge frequency; A product of the first ratio parameter and the second threshold is determined as the first threshold.

[0052] It should be understood that in this embodiment, batteries with different chemical compositions (such as lead-acid batteries and lithium-ion batteries) have different characteristics and performance difference ranges. For example, lithium-ion batteries usually have high requirements for the consistency of voltage and power, and the corresponding second threshold can be set relatively strictly; while the performance difference of lead-acid batteries is relatively large, and the threshold may be appropriately relaxed. At the same time, the capacity of the battery pack will also affect the setting of the second threshold. For large-capacity batteries, due to the large amount of energy stored, more sophisticated management is required during the charging and discharging process, and the tolerance for monomer differences is relatively low, so a smaller second threshold can be set. Therefore, this embodiment can determine the corresponding second threshold based on the chemical composition and capacity level of the battery pack. Specifically, by analyzing the historical operation data of battery packs with different chemical compositions and different capacities, the mapping relationship between the chemical composition, capacity level and the second threshold of the battery pack can be pre-constructed. When performing the equalization control of the battery pack, the mapping relationship can be searched based on the chemical composition and capacity level of the actual battery pack to obtain the corresponding second threshold.

[0053] It should be understood that, considering that the frequency of charge and discharge will also affect the performance of the single cell, frequent charge and discharge will accelerate the aging and performance difference of the battery, so the battery pack with high charge and discharge frequency is more likely to be unbalanced. Therefore, when setting the second threshold, the influence of the charge and discharge frequency should also be considered. For example, the battery pack is used in scenarios with frequent charge and discharge, such as electric bicycles, uninterruptible power supplies, etc., and a smaller second threshold can be set to adjust the difference between the single cells in time to extend the life of the entire battery pack. For another example, for scenarios with low charge and discharge frequencies, such as solar energy storage systems, because the battery pack has more time to self-balance in an idle state, a larger second threshold can be set to avoid unnecessary balancing operations. During the balancing operation, energy needs to be transferred from high-power single cells to low-power single cells, and there is energy loss during the transfer process. Avoiding unnecessary balancing operations can reduce energy loss and improve resource utilization efficiency. Therefore, on the basis of determining the corresponding second threshold based on the chemical composition and capacity level of the battery pack, the second threshold can be adjusted based on the charge and discharge frequency of the battery pack to obtain the final second threshold.

[0054] Specifically, the reference value of the charge and discharge frequency can be preset , then based on the measured value of the charge and discharge frequency and the reference value of charge and discharge frequency The first adjustment parameter is obtained as shown in formula (5): (5) Among them, k1 is the first adjustment parameter, is a preset constant, is the preset reference value of the charge and discharge frequency, It is the measured value of charge and discharge frequency.

[0055] And the second threshold is adjusted based on the first adjustment parameter, as shown in calculation formula (6): (6) Wherein, x′ is the final second threshold value, x is the second threshold value determined based on the chemical composition and capacity level of the battery pack, and k1 is the first adjustment parameter.

[0056] It should be understood that in this embodiment, the measured value of the charge and discharge frequency The base value of the charge and discharge frequency can be obtained by counting the charge and discharge time of the battery pack. It can be set based on experience. For example, the charge and discharge frequency of the battery pack in different application scenarios (such as electric vehicles, electric bicycles, uninterruptible power supplies, solar energy storage systems, etc.) is counted, and the average value of the charge and discharge frequency of multiple application scenarios is calculated to obtain the benchmark value of the charge and discharge frequency. .

[0057] It can be concluded from the above that this embodiment comprehensively considers factors such as the chemical composition, capacity level, and charge and discharge frequency of the battery pack to determine the second threshold, and can reduce unnecessary balancing operations as much as possible on the basis of meeting the balancing requirements of the battery pack.

[0058] It should also be understood that in this embodiment, the first proportional parameter is a constant greater than 1, and both the first threshold and the second threshold are affected by the chemical composition, capacity level and charge and discharge frequency of the battery pack. Therefore, on the basis of determining the second threshold, the second threshold is multiplied by the first proportional parameter to obtain the first threshold, which can realize the linkage of the first threshold and the second threshold, and maintain the consistency of the first threshold and the second threshold. The first threshold is used as the dividing point between the constant current control strategy and the constant voltage control strategy. By adjusting the specific value of the first proportional parameter, the action time of the constant current control strategy and the constant voltage control strategy can be adjusted, thereby adjusting the balancing effect of the entire battery pack.

[0059] For example, in a scenario where the balancing speed is required to be high, the first proportional parameter can be set to be small, so that the first threshold is low, which can increase the action time of the constant current control strategy and speed up the balancing process. In a scenario where the balancing accuracy is required to be high, the first proportional parameter can be set to be large, so that the first threshold is high, so as to increase the action time of the constant voltage control, more accurately control the balancing process, and improve the balancing effect.

[0060] In the above manner, this embodiment can adjust the size of the first threshold by adjusting the specific value of the first proportional parameter, thereby adjusting the action time of the constant current control strategy and the constant voltage control strategy to meet the actual needs of multiple application scenarios.

[0061] In a possible implementation, dynamically balancing the battery pack based on the constant current control strategy may include: According to the first difference corresponding to each single cell, a plurality of first single cells and a plurality of second single cells are determined, wherein the first single cell is a single cell whose corresponding first difference is greater than a second threshold value, and the second single cell is a single cell whose corresponding first difference is less than 0 and whose absolute value of the first difference is greater than the second threshold value; In the case where the preference information input by the user is the first preference information, according to the power value corresponding to each single battery, the single battery with the largest power value among the plurality of first single batteries is determined as the third single battery, and the single battery with the smallest power value among the plurality of second single batteries is determined as the fourth single battery; In the case where the preference information input by the user is the second preference information, according to the internal resistance value corresponding to each single cell, the single cell with the smallest internal resistance value among the plurality of first single cells is determined as the third single cell, and the single cell with the largest internal resistance value among the plurality of second single cells is determined as the fourth single cell; Transferring the energy of the third single cell to the fourth single cell, and when the absolute value of the first difference corresponding to any single cell is less than or equal to the second threshold, updating the first difference corresponding to the current third single cell and the current fourth single cell respectively; According to the updated first difference, the step of determining a plurality of first single cells and a plurality of second single cells according to the first difference corresponding to each single cell is returned to and executed until the absolute value of the first difference corresponding to each single cell is less than or equal to the second threshold.

[0062] It should be understood that in this embodiment, by comparing the absolute value of the first difference with the second threshold, the single cells with large differences in the battery pack can be obtained. Further, by comparing the first difference with 0, it can be determined which single cells have too high power and need to be discharged (first single cells) and which single cells have too low power and need to be charged (second single cells). Specifically, if the first difference corresponding to a single cell among multiple single cells with differences is greater than 0, it indicates that the voltage of the single cell is higher than the average voltage of the battery pack, or the power of the single cell is higher than the average power of the battery pack, and the single cell can be marked as the first single cell (or a high-power single cell). If the first difference corresponding to a single cell among multiple single cells with differences is less than 0, it indicates that the voltage of the single cell is lower than the average voltage of the battery pack, or the power of the single cell is lower than the average power of the battery pack, and the single cell can be marked as the second single cell (or a low-power single cell).

[0063] It should be understood that, based on obtaining multiple first single cells and multiple second single cells, by performing single cell screening operations multiple times, the third single cell and the fourth single cell that meet the set conditions can be screened out in turn, and the energy of the third single cell can be transferred to the fourth single cell, gradually reducing the difference between the first single cell and the second single cell, until the absolute values ​​of the first differences corresponding to all single cells are less than or equal to the second threshold value, so as to achieve a balanced state of the battery pack.

[0064] It should also be understood that during each single cell screening operation, after the energy of the third single cell is transferred to the fourth single cell, the electrical energy of the third single cell and the fourth single cell will change. Therefore, it is necessary to update the first difference corresponding to the third single cell and the fourth single cell after each single cell screening operation is completed. When performing the next single cell screening operation, the first single cell and the second single cell can be screened according to the latest single cell operating parameters.

[0065] It should also be understood that during the single cell screening operation, the screening conditions (i.e., setting conditions) can be determined according to the user's preference information. The user's preference information includes first preference information and second preference information, wherein the first preference information indicates that the user pays more attention to the balancing speed, and the second preference information indicates that the user pays more attention to the balancing efficiency. The user's preference information can be input when the system is initialized, and can also be changed at any time during the operation of the system.

[0066] For example, the user can set preference information according to the application scenario of the battery pack. For example, during the driving of an electric vehicle, if the single cells in the battery pack are unbalanced, the vehicle's range and performance will be affected. Therefore, in this scenario, the preference information can be set to the first preference information to achieve rapid balancing of the battery pack and reduce the range reduction and power shortage problems caused by imbalance. For another example, in a solar energy storage system, the battery pack needs to run for a long time, and the life and performance requirements of the battery pack are high. If the battery pack is unbalanced, some single cells will be overcharged or over-discharged, shortening the life of the battery pack. Therefore, high-precision balancing is required to ensure that the single cells in the battery pack are always in the best working condition. In this scenario, the preference information can be set to the second preference information to ensure that the single cells in the battery pack are always in the best working condition.

[0067] It should be understood that during the single cell screening operation, if the user's preference information is the first preference information, the first single cell with the largest power can be selected as the third single cell based on the power size, and the second single cell with the smallest power can be selected as the fourth single cell, and the energy of the third single cell can be transferred to the fourth single cell. The single cell with the largest power difference is selected first for energy transfer, which can quickly narrow the power gap and improve the balancing speed.

[0068] It should be understood that during the cell screening operation, if the user's preference information is the second preference information, the first cell with the smallest internal resistance can be selected as the third cell based on the internal resistance, and the second cell with the smallest power can be selected as the fourth cell, and the energy of the third cell can be transferred to the fourth cell. Since a cell with a lower power than a cell with a higher internal resistance will be assigned a higher voltage drop under the same current, it is easier for energy to flow from a cell with a higher power to a cell with a lower power, thereby improving the energy transfer efficiency.

[0069] In the above manner, this embodiment uses multiple screening operations to selectively select single cells for energy transfer according to different preference information, which can more efficiently achieve balancing of the battery pack and meet balancing requirements in different application scenarios.

[0070] In a possible implementation manner, transferring the energy of the third single cell to the fourth single cell may include: During the first preset period, the energy storage element is charged through the third single battery, and during the second preset period, the fourth single battery is charged through the energy storage element.

[0071] It should be understood that the process of transferring the energy of the third single cell to the fourth single cell may also be referred to as a dynamic balancing operation. In other words, the dynamic balancing operation may include: charging the energy storage element through the third single cell in the first period, and charging the fourth single cell through the energy storage element in the second period.

[0072] For example, in this embodiment, in the process of transferring the energy of the third single cell to the fourth single cell, a corresponding energy storage element (such as an inductor or a capacitor and two switches (such as MOSFET) can be provided for each single cell, and the energy of the third single cell is transferred to the fourth single cell by controlling the on and off of the switches.

[0073] The specific process can be as follows: 1) Close the switch corresponding to the third single battery, so that the third single battery charges the energy storage element. The energy storage element stores energy, and the charging time of the energy storage element can be controlled by setting the first time period.

[0074] 2) After the first period ends, the switch is turned off, and then the switch corresponding to the fourth single cell is closed, and the energy storage element releases energy to the fourth single cell. The discharge time of the energy storage element can be controlled by setting the second period.

[0075] 3) Repeat the above process until the first difference corresponding to the third single cell is less than the second threshold, or the absolute value of the first difference corresponding to the fourth single cell is less than the second threshold, that is, the third single cell or the fourth single cell reaches the balancing target.

[0076] The following takes the user's preference information as the first preference information as an example to illustrate the multiple execution processes of the single cell screening operation. Specifically, during the first single cell screening operation, if the power of single cell A is the largest and the power of single cell B is the smallest based on the power size, the dynamic balancing operation is performed multiple times to transfer the energy of single cell A to single cell B. If after a certain execution of the dynamic balancing operation, the first difference corresponding to single cell B is less than or equal to the second threshold value, that is, single cell B reaches a balanced state, the multiple dynamic balancing operations are stopped and the second single cell screening operation is started.

[0077] During the second single-cell battery screening operation, if based on the power size, it is found that single-cell battery A still has the largest power and single-cell battery C has the smallest power, the dynamic balancing operation is performed multiple times to transfer the energy of single-cell battery A to single-cell battery C. If after a certain dynamic balancing operation is performed, the first difference corresponding to single-cell battery C is less than or equal to the second threshold value, that is, single-cell battery C reaches a balanced state, then the multiple dynamic balancing operations are stopped and the third single-cell battery screening operation is started.

[0078] During the third single-cell battery screening operation, if based on the power size, it is obtained that the power of single-cell battery D is the largest and the power of single-cell battery E is the smallest, the dynamic balancing operation is performed multiple times to transfer the energy of single-cell battery D to single-cell battery E. If after a certain dynamic balancing operation is performed, the first difference corresponding to single-cell battery D is less than or equal to the second threshold value, that is, single-cell battery D reaches a balanced state, then the multiple dynamic balancing operations are stopped and the fourth single-cell battery screening operation is started.

[0079] The above process is repeated until the absolute values ​​of the first differences corresponding to all single cells are less than or equal to the second threshold value, that is, all single cells reach a balanced state.

[0080] In the above manner, the embodiment performs the dynamic balancing operation multiple times to ensure that the battery pack gradually reaches a balanced state, thereby avoiding the problem of system instability caused by one-time over-balancing.

[0081] Figure 2 A battery dynamic balancing management device 200 is shown according to an exemplary embodiment of the present disclosure. Figure 2 As shown, the battery dynamic balancing management device 200 may include: A determination module 201 is used to determine a first difference between an operating parameter of each single cell in the battery pack and an average operating parameter of the battery pack, wherein the average operating parameter of the battery pack is an average value of the operating parameter of each single cell in the battery; A first balancing management module 202, configured to perform dynamic balancing management on the battery pack based on a constant current control strategy when the absolute value of the first difference is greater than a first threshold; The second balancing management module 203 is configured to perform dynamic balancing management on the battery pack based on a constant voltage control strategy when the absolute value of the first difference is greater than the second threshold and less than the first threshold.

[0082] Optionally, the determination module 201 is used to: When the usage time of the storage battery group is less than or equal to the first time, determining the difference between the voltage of each single cell and the average voltage of the storage battery group as the first difference; When the usage time of the storage battery pack is greater than the first time, the difference between the power of each single cell and the average power of the storage battery pack is determined as the first difference.

[0083] Optionally, the battery dynamic balancing management device 200 further includes: An acquisition module is used to obtain the real-time temperature and load change rate of the battery pack; The parameter determination module is used to determine a first proportional parameter according to the real-time temperature and the load change rate, wherein the real-time temperature and the load change rate are both proportional to the first proportional parameter.

[0084] Optionally, the parameter determination module is used to: Determine a second proportional parameter according to the real-time temperature; Determining a third proportional parameter according to the load change rate; The second proportional parameter and the third proportional parameter are weighted and summed to obtain the first proportional parameter.

[0085] Optionally, the battery dynamic balancing management device 200 further includes a threshold determination module, which is used to: Obtain the chemical composition, capacity level, and charge and discharge frequency of the battery pack; Determining a second threshold value according to the chemical composition, capacity level, and charge and discharge frequency; A product of the first ratio parameter and the second threshold is determined as the first threshold.

[0086] Optionally, the first balancing management module 202 includes: A first determination submodule, configured to determine a plurality of first single cells and a plurality of second single cells according to the first difference corresponding to each single cell, wherein the first single cell is a single cell whose corresponding first difference is greater than a second threshold value, and the second single cell is a single cell whose corresponding first difference is less than 0 and whose absolute value of the first difference is greater than the second threshold value; A second determination submodule is used for, when the preference information input by the user is the first preference information, determining, according to the power value corresponding to each single battery, a single battery with the largest power value among the plurality of first single batteries as the third single battery, and determining a single battery with the smallest power value among the plurality of second single batteries as the fourth single battery; a third determination submodule, configured to, when the preference information input by the user is the second preference information, determine, according to the internal resistance value corresponding to each single cell, a single cell with the smallest internal resistance value among the plurality of first single cells as a third single cell, and determine a single cell with the largest internal resistance value among the plurality of second single cells as a fourth single cell; An energy transfer submodule, used for transferring energy from the third single cell to the fourth single cell, and updating the first difference values ​​corresponding to the current third single cell and the current fourth single cell respectively when the absolute value of the first difference value corresponding to any single cell is less than or equal to the second threshold value; The balancing management submodule is used to return to the step of determining multiple first single cells and multiple second single cells according to the first difference corresponding to each single cell according to the updated first difference, until the absolute value of the first difference corresponding to each single cell is less than or equal to the second threshold.

[0087] Optionally, the energy transfer submodule is used to: During the first preset period, the energy storage element is charged through the third single battery, and during the second preset period, the fourth single battery is charged through the energy storage element.

[0088] Regarding the device in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0089] Figure 3 FIG. 1 is a block diagram of an electronic device 300 according to an exemplary embodiment of the present disclosure. Figure 3 As shown, the electronic device 300 may include: a processor 301 , a memory 302 . The electronic device 300 may also include one or more of a multimedia component 303 , an input / output (I / O) interface 304 , and a communication component 305 .

[0090] The processor 301 is used to control the overall operation of the electronic device 300 to complete all or part of the steps in the above-mentioned dynamic equalization management method for storage batteries. The memory 302 is used to store various types of data to support the operation of the electronic device 300, and these data may include, for example, instructions for any application or method used to operate on the electronic device 300, and data related to the application. The memory 302 can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (Static Random Access Memory, referred to as SRAM), electrically erasable programmable read-only memory (Electrically Erasable Programmable Read-Only Memory, referred to as EEPROM), erasable programmable read-only memory (Erasable Programmable Read-Only Memory, referred to as EPROM), programmable read-only memory (Programmable Read-Only Memory, referred to as PROM), read-only memory (Read-Only Memory, referred to as ROM), magnetic memory, flash memory, magnetic disk or optical disk. The multimedia component 303 may include a screen and an audio component. The screen may be, for example, a touch screen, and the audio component is used to output and / or input audio signals. For example, the audio component may include a microphone for receiving external audio signals. The received audio signal may be further stored in the memory 302 or sent through the communication component 305. The audio component also includes at least one speaker for outputting audio signals. The I / O interface 304 provides an interface between the processor 301 and other interface modules, and the other interface modules may be keyboards, mice, buttons, etc. These buttons may be virtual buttons or physical buttons. The communication component 305 is used for wired or wireless communication between the electronic device 300 and other devices. Wireless communication, such as Wi-Fi, Bluetooth, Near Field Communication (NFC), 2G, 3G, 4G, NB-IOT, eMTC, or other 5G, etc., or a combination of one or more of them, is not limited here. Therefore, the corresponding communication component 305 may include: Wi-Fi module, Bluetooth module, NFC module, etc.

[0091] In an exemplary embodiment, the electronic device 300 may be implemented by one or more application specific integrated circuits (ASIC), digital signal processors (DSP), digital signal processing devices (DSPD), programmable logic devices (PLD), field programmable gate arrays (FPGA), controllers, microcontrollers, microprocessors or other electronic components to execute the above-mentioned battery dynamic balancing management method.

[0092] In another exemplary embodiment, a computer-readable storage medium including program instructions is also provided, and when the program instructions are executed by a processor, the steps of the above-mentioned battery dynamic balancing management method are implemented. For example, the computer-readable storage medium can be the above-mentioned memory 302 including program instructions, and the above-mentioned program instructions can be executed by the processor 301 of the electronic device 300 to complete the above-mentioned battery dynamic balancing management method.

[0093] The preferred embodiments of the present disclosure are described in detail above in conjunction with the accompanying drawings; however, the present disclosure is not limited to the specific details in the above embodiments. Within the technical concept of the present disclosure, a variety of simple modifications can be made to the technical solution of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0094] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0095] In addition, various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A method for dynamic equalization management of batteries, characterized in that: The method comprises: Determine a first difference between an operating parameter of each single cell in the battery pack and an average operating parameter of the battery pack, wherein the average operating parameter of the battery pack is an average value of the operating parameters of each single cell in the battery; When the absolute value of the first difference is greater than a first threshold, dynamically balancing the battery pack based on a constant current control strategy; When the absolute value of the first difference is greater than the second threshold and less than the first threshold, dynamic balancing management is performed on the battery pack based on a constant voltage control strategy.

2. The method according to claim 1, characterized in that The step of determining a first difference between an operating parameter of each single cell in the battery pack and an average operating parameter of the battery pack comprises: When the usage time of the storage battery pack is less than or equal to the first time time, determining the difference between the voltage of each single cell and the average voltage of the storage battery pack as the first difference; When the usage time of the storage battery pack is greater than the first time, the difference between the power of each single cell and the average power of the storage battery pack is determined as the first difference.

3. The method according to claim 1, characterized in that The method further comprises: Obtaining the real-time temperature and load change rate of the battery pack; A first proportional parameter is determined according to the real-time temperature and the load change rate, wherein the real-time temperature and the load change rate are both proportional to the first proportional parameter.

4. The method according to claim 3, characterized in that The determining a first proportional parameter according to the real-time temperature and the load change rate comprises: Determining a second proportional parameter according to the real-time temperature; Determining a third proportional parameter according to the load change rate; The first proportion parameter is obtained by weighted summing the second proportion parameter and the third proportion parameter.

5. The method according to claim 3, characterized in that: The method further comprises: Obtaining the chemical composition, capacity level and charge and discharge frequency of the battery pack; determining the second threshold value according to the chemical composition, the capacity level and the charge and discharge frequency; The product of the first ratio parameter and the second threshold is determined as the first threshold.

6. The method according to claim 1, characterized in that The dynamic balancing management of the battery pack based on the constant current control strategy includes: Determine a plurality of first single cells and a plurality of second single cells according to the first difference corresponding to each single cell, wherein the first single cell is a single cell whose corresponding first difference is greater than the second threshold, and the second single cell is a single cell whose corresponding first difference is less than 0 and whose absolute value of the first difference is greater than the second threshold; In the case where the preference information input by the user is the first preference information, according to the power value corresponding to each single battery, the single battery with the largest power value among the plurality of the first single batteries is determined as the third single battery, and the single battery with the smallest power value among the plurality of the second single batteries is determined as the fourth single battery; In the case where the preference information input by the user is the second preference information, according to the internal resistance value corresponding to each single cell, the single cell with the smallest internal resistance value among the plurality of the first single cells is determined as the third single cell, and the single cell with the largest internal resistance value among the plurality of the second single cells is determined as the fourth single cell; Transferring the energy of the third single cell to the fourth single cell, and when the absolute value of the first difference corresponding to any single cell is less than or equal to the second threshold, updating the first difference corresponding to the current third single cell and the current fourth single cell respectively; According to the updated first difference, return to the step of determining a plurality of first single cells and a plurality of second single cells according to the first difference corresponding to each single cell, until the absolute value of the first difference corresponding to each single cell is less than or equal to the second threshold.

7. The method according to claim 6, characterized in that The step of transferring the energy of the third single cell to the fourth single cell comprises: During a first preset period of time, the energy storage element is charged through the third single battery, and during a second preset period of time, the fourth single battery is charged through the energy storage element.

8. A battery dynamic equalization management device, characterized in that: The device comprises: A determination module, configured to determine a first difference between an operating parameter of each single cell in a storage battery pack and an average operating parameter of the storage battery pack, wherein the average operating parameter of the storage battery pack is an average value of the operating parameters of each single cell in the storage battery; A first balancing management module, configured to perform dynamic balancing management on the battery pack based on a constant current control strategy when an absolute value of the first difference is greater than a first threshold; The second balancing management module is used to perform dynamic balancing management on the battery group based on a constant voltage control strategy when the absolute value of the first difference is greater than a second threshold and less than the first threshold.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

10. An electronic device, characterized in that: include: a memory having a computer program stored thereon; A processor, configured to execute the computer program in the memory to implement the steps of the method according to any one of claims 1 to 7.

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