Balancing method, balancing device and storage medium

Abstract

The invention discloses an equalization method, equalization equipment and a storage medium, the equalization method is applied to a battery pack, the battery pack comprises a plurality of battery cells, the equalization method comprises the following steps: obtaining voltage data of each battery cell in the nth charging process, n > = 1, and the voltage data of each battery cell in the nth charging process comprises a first average voltage and a maximum voltage; obtaining a threshold value of the corresponding battery cell based on the first average voltage and the highest voltage; in the (n + 1) th charging process, the voltage of each battery cell is obtained in real time, and when the voltage of one target battery cell is larger than or equal to a threshold value, the first number of times that the voltage of the target battery cell is larger than or equal to the threshold value is obtained; and when the first number of times is greater than or equal to the first preset number of times, the voltage of the target battery cell is reduced, and the equalization efficiency of the battery cell needing passive equalization is improved.

Description

Technical Field

[0001] This invention relates to the field of energy storage technology, specifically to a balancing method, balancing equipment, and storage medium. Background Technology

[0002] Currently, passive balancing technology in battery management systems achieves voltage equalization among battery cells by consuming battery energy. It utilizes energy-consuming components to release excess energy from high-voltage batteries as heat, thereby bringing the voltage of the entire battery pack closer together. In existing technologies, passive balancing technology in battery management systems is generally only activated towards the end of the charging process. Moreover, passive balancing is only activated for a cell whose maximum single-cell voltage exceeds a fixed threshold. Because the identification of cells requiring passive balancing is inaccurate and the charging end period is short, the balancing efficiency for cells requiring passive balancing is low. Summary of the Invention

[0003] The purpose of this invention is to provide an equalization method, equalization device, and storage medium, which improves the problem of low equalization efficiency for battery cells that require passive equalization.

[0004] To achieve the objectives of this invention, the following technical solution is provided: In a first aspect, the present invention provides an equalization method applied to a battery pack, the battery pack comprising multiple battery cells, the equalization method comprising: acquiring voltage data of each battery cell in the nth charging process, where n≥1, the voltage data of each battery cell in the nth charging process comprising a first average voltage and a maximum voltage; obtaining a threshold for the corresponding battery cell based on the first average voltage and the maximum voltage; in the (n+1)th charging process, acquiring the voltage of each battery cell in real time, and when the voltage of a target battery cell is greater than or equal to the threshold, acquiring a first number of times the voltage of the target battery cell is greater than or equal to the threshold; when the first number of times is greater than or equal to a first preset number of times, reducing the voltage of the target battery cell.

[0005] It is understandable that determining the threshold based on the actual voltage data of the cell's previous (nth) charge (the first average voltage reflects the cell's normal charging state, and the highest voltage reflects its voltage upper limit characteristic) deeply binds the threshold to the cell's own historical charging characteristics (which have historical voltage memory function), rather than a fixed value detached from reality. This allows for dynamic adaptation to changes in the cell's state, avoiding the adaptability defects of fixed thresholds. Introducing a trigger condition where the first number is greater than or equal to the first preset number requires confirmation of voltage exceeding the limit through multiple monitoring sessions, rather than a single trigger. This effectively filters out interference from instantaneous voltage fluctuations, ensuring that the cell triggering equalization is indeed in a continuously high voltage state. This method significantly improves the accuracy and reliability of equalization triggering. The adaptive threshold design allows the equalization action to accurately match the actual state of the cell, avoiding cell overvoltage damage caused by missed equalization or energy loss caused by incorrect equalization. The multiple confirmation mechanism reduces the impact of instantaneous fluctuations, protecting normal cells from unnecessary voltage reduction operations and extending cell cycle life. Meanwhile, by continuously handling high-voltage cells throughout the charging process, the voltage consistency of cells within the battery pack can be effectively maintained, preventing overvoltage of a single cell from affecting the charging and discharging efficiency and safety of the entire battery pack, and improving the overall performance stability of the battery pack. In one embodiment, the charging process includes a charging phase. When the battery pack is in the charging phase, the threshold corresponding to the battery cell is obtained based on the first average voltage and the highest voltage using the following formula: V1≥(V2×K1+V3) / K2, where V1 is the threshold, K1 is a preset first coefficient, K2 is a preset second coefficient, V2 is the first average voltage, and V3 is the highest voltage.

[0006] It's understandable that assigning a 2 / 3 weight to the first average voltage and a 1 / 3 weight to the highest voltage ensures that, during the charging phase, the first average voltage better reflects the overall normal charging voltage level of the cells within the battery pack, serving as a benchmark for determining whether a cell has an abnormally high voltage. The highest voltage, on the other hand, reflects the cell's own voltage limit, preventing the threshold from deviating from the individual characteristics of each cell. The threshold calculation during the charging phase balances both the group benchmark and individual characteristics, using the first average voltage as the primary reference to ensure that the balancing action does not excessively interfere with normally charging cells, reducing unnecessary energy loss and improving charging efficiency. Furthermore, incorporating the highest voltage parameter prevents balancing from failing to trigger even when the cell voltage is close to its own upper limit, reducing the safety risk of overvoltage charging. This design allows the threshold to dynamically adapt to scenarios with rapid voltage changes during the charging phase, improving the accuracy of threshold determination and precisely controlling the timing of balancing triggering.

[0007] In one embodiment, the charging process further includes a resting phase. When the battery pack is in the resting phase, the threshold value corresponding to the battery cell is obtained based on the first average voltage and the highest voltage using the following formula: V1≥(V2×K1+V3) / K2+V4, where V4 is a preset offset value.

[0008] It is understandable that the threshold design during the resting phase achieves precise staged adaptation. By adjusting the threshold through a preset offset value, it avoids misjudgment or missed judgment of the threshold during the resting phase in the charging phase, reduces the impact of erroneous equalization on normal cells, and ensures that potential voltage anomalies can be detected in a timely manner. The flexibility of the preset offset value allows the method to adapt to the resting voltage characteristics of different types of batteries (such as ternary lithium batteries and lithium iron phosphate batteries) or the needs of different resting durations (such as short-term resting and long-term storage), enhancing the versatility of the method, improving the accuracy of threshold determination, and precisely controlling the timing of equalization triggering. In one embodiment, before reducing the voltage of the target battery cell, the method further includes: When there is a target cell whose voltage is greater than or equal to the threshold, the target cell is determined to be a high-voltage cell.

[0009] It is understandable that when the voltage of a target battery cell is greater than or equal to a threshold, the target battery cell is determined to be a high-voltage battery cell. Subsequently, the information of the high-voltage battery cell can be sent to the user, and the user can then decide on the measures to be taken, thereby enhancing the practicality, interactivity and reliability of the method. In one embodiment, reducing the voltage of the target battery cell when the first number of times is greater than or equal to a first preset number of times includes: When the voltage of a target battery cell is greater than or equal to the threshold, the voltage of the target battery cell is obtained a first number of times within a first preset time period.

[0010] The first preset duration is understood to be a time window for counting the number of cycles, ensuring that the counting focuses on a continuous state within a short period, avoiding delays caused by unlimited time. Triggering is only triggered when a certain number of cycles are reached within this time window, filtering out instantaneous fluctuations. This design provides sufficient time to confirm whether the voltage is continuously high without the risk of overvoltage due to excessively long counting time. The setting of the first preset duration avoids balancing delays caused by unlimited counting, ensuring that high-voltage cells can be processed quickly, reducing damage to the cells from overvoltage conditions and improving safety. Simultaneously, the first preset duration and the first preset number of cycles can be flexibly adjusted according to the charging current and cell type. During high-current charging, the cell voltage rises rapidly, so the duration can be shortened and the number of cycles reduced to avoid overvoltage; during low-current charging, the duration can be extended and the number of cycles increased to filter more fluctuations and enhance the method's adaptability. This design further improves the accuracy and timeliness of balancing triggering. In one embodiment, the step of obtaining a first number of times that the voltage of the target battery cell is greater than or equal to the threshold within a first preset time period includes: At each second preset time interval, the voltage of the target battery cell is obtained a first number of times that is greater than or equal to the threshold.

[0011] It is understandable that, at each second preset time interval, the number of times the voltage of the target battery cell is greater than or equal to the threshold is obtained. Fixed-interval uniform sampling ensures that the statistical count accurately reflects the voltage state of the battery cell within the first preset time interval, avoiding false or missed triggers caused by sampling deviations and improving the accuracy of balanced triggering. Furthermore, the second preset time interval can be adjusted according to the rate of change of the battery cell voltage (e.g., a shorter interval when the voltage rises rapidly to ensure no critical states are missed; a longer interval when the voltage is stable to reduce hardware resource consumption), enhancing the flexibility of the method and improving the accuracy of obtaining the first count. In one embodiment, the step of reducing the voltage of the target battery cell when the first number of times is greater than or equal to a first preset number of times further includes: During the (n+1)th charging process, the second average voltage of the multiple battery cells is acquired in real time. The voltage of the target cell is reduced to the second average voltage.

[0012] It is understandable that the real-time dynamic voltage reduction target design significantly improves the voltage consistency of the battery pack. By reducing the target cell to the current second average voltage, it avoids the ineffective balancing caused by a fixed target, ensuring that all cells in the battery pack are always at a similar voltage level, thus improving the overall charging and discharging efficiency (cells with consistent voltage can work together, preventing some cells from failing to discharge due to excessively low voltage or failing to charge due to excessively high voltage). Simultaneously, real-time acquisition of the second average voltage allows the balancing target to adapt to voltage changes during the charging process. Furthermore, improved voltage consistency reduces circulating current losses between cells, lowers the overall energy loss of the battery pack, and extends cell cycle life. This design effectively maintains long-term consistency between cells, ensuring the long-term performance stability of the battery pack.

[0013] In one embodiment, reducing the voltage of the target battery cell to the second average voltage voltage includes: The target battery cell is controlled to discharge and equalize to a first voltage using a first equalizing current, wherein the first voltage is greater than the second average voltage. The target cell is controlled to discharge from the first voltage to the second average voltage using a second equalizing current, wherein the second equalizing current is less than the first equalizing current.

[0014] The first stage, rapid voltage reduction with high current, significantly shortens the overvoltage time of the target cell, reducing damage caused by overvoltage (such as electrolyte decomposition and electrode material detachment), improving safety, and shortening balancing time without affecting overall charging efficiency. The second stage, precise voltage control with low current, avoids imbalances caused by voltage overshoot, ensuring a perfect match between the target cell voltage and the second average voltage, maintaining battery pack voltage consistency. Furthermore, low-current discharge has less impact on the cell, reducing polarization effects during discharge, lowering the risk of internal temperature rise, further protecting the cell structure, and extending cycle life. This design meets the demands of fast charging while ensuring accurate balancing and cell safety, improving the overall performance of the battery pack. In a second aspect, embodiments of this application provide an equalization device, including a processor, a memory, and at least one program, wherein the at least one program is stored in the memory and configured to be executed by the processor, the program including instructions for performing any of the methods in the first aspect.

[0015] Thirdly, embodiments of this application provide a computer-readable storage medium storing a computer program that causes a computer to execute to implement the method described in any one of the first aspects. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram illustrating an application scenario of an equilibrium method according to one embodiment. Figure 2 This is a flowchart illustrating an embodiment of an balancing method; Figure 3 This is a schematic diagram of the structure of an equalization device according to one embodiment; Figure 4 This is a diagram illustrating the equalization function that enables charging throughout all time periods, as described in one embodiment. Figure 5 This is a schematic diagram of the voltage distribution at the charging end of a conventional strategy according to one embodiment; Figure 6 This is a schematic diagram of the optimized charging terminal voltage distribution of one embodiment.

[0018] Explanation of reference numerals in the attached figures: 101-User, 102-Battery pack, 103-Equalizing device, 301-Processor, 302-Memory, 303-Program. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] It should be noted that when a component is said to be "fixed" to another component, it can be directly on the other component or it can be in a middle component. When a component is said to be "connected" to another component, it can be directly connected to the other component or it may be in a middle component.

[0021] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used in this invention includes any and all combinations of one or more of the associated listed items.

[0022] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0023] Please see Figure 1 , Figure 1 This is a schematic diagram illustrating an application scenario of an balancing method provided in an embodiment of this application. For example... Figure 1 As shown in the diagram, this application scenario includes a user 101, a battery pack 102, and an equalization device 103. Optionally, the battery pack 102 includes multiple battery cells.

[0024] It should be noted that, Figure 1 The number and form of each device in the system shown, as well as the number of users 101 and equalization devices 103, are for illustrative purposes only and do not constitute a limitation on the embodiments of this application.

[0025] User 101 can operate the equalization device 103 to perform corresponding actions on the battery pack 102.

[0026] The equalization method provided in the embodiments of this application is described below. The equalization method can be executed by equalization device 103, which can be implemented by software and / or hardware.

[0027] Please refer to Figure 2 , Figure 2 This is a flowchart illustrating an balancing method provided in an embodiment of this application. An example is given of the method applied to the balancing process. The balancing method includes the following steps S201-S204, wherein... S201: Obtain the voltage data of each cell during the nth charging process, where n≥1. The voltage data of each cell during the nth charging process includes the first average voltage and the highest voltage.

[0028] S202: Obtain the threshold value of the corresponding cell based on the first average voltage and the highest voltage.

[0029] The charging process includes a charging phase. When the battery pack is in the charging phase, the threshold of the corresponding cell is obtained based on the first average voltage and the highest voltage, using the following formula: V1≥(V2×K1+V3) / K2, where V1 is the threshold, K1 is the preset first coefficient, K2 is the preset second coefficient, V2 is the first average voltage, and V3 is the highest voltage.

[0030] Optionally, in the existing strategy, the threshold is ≥ (average voltage + minimum voltage) / 2 + 20mV. This existing strategy is based on the arithmetic mean of the average voltage and the minimum voltage, with an additional fixed offset. This has the following problems: First, it is sensitive to the minimum voltage, which may be an anomaly of an individual cell (such as cell failure or partial discharge) and does not represent overall inconsistency. Using the minimum voltage lowers the threshold, causing many cells with voltages slightly higher than the average voltage to also meet the balancing conditions, triggering unnecessary balancing actions and increasing energy loss and thermal management burden. Second, the fixed offset has limitations. A fixed offset of 20mV lacks adaptability; when the voltage difference is small, the threshold is too high (insufficient balancing); when the voltage difference is large, the threshold may be too low (over-balancing).

[0031] The optimization strategy in this application adopts a weighted average form, expressing the threshold as V1≥(V2×K1+V3) / K2, which has the following advantages: First, for high-voltage cells, the highest voltage is directly introduced, focusing on the cells with the highest voltage. This aligns with the goal of passive equalization, which achieves equalization by discharging high-voltage cells, avoiding false responses to low-voltage cells. Second, this formula allows for adaptive threshold adjustment. Through multiple tests, K1 is set to 2 and K2 to 3, allocating 2 / 3 of the weight to the first average voltage and 1 / 3 to the highest voltage, placing the threshold between the highest voltage and the first average voltage. As the cell voltage difference increases, the threshold increases accordingly, initiating equalization only for cells with significantly higher voltages. When the difference decreases, the threshold decreases, improving equalization sensitivity. Furthermore, this formula can improve equalization efficiency by reducing unnecessary equalization actions, lowering energy loss, extending battery life, and maintaining battery pack voltage consistency. In summary, existing strategies are simple arithmetic averages that do not distinguish the weights of voltage distribution and rely on extremely low values. In contrast, the optimized strategy of this application uses a weighted average to give the first average voltage a higher weight to reflect the overall state, while incorporating the highest voltage to highlight abnormally high values, thereby setting the equilibrium trigger point more scientifically.

[0032] It should be noted that using only the first average voltage can easily lead to an excessively low threshold, resulting in frequent equalization (even if the cell voltage is slightly higher than the average but has not reached the safety risk limit, voltage reduction is still triggered), wasting energy and affecting charging efficiency; using only the highest voltage can easily lead to an excessively high threshold, resulting in delayed equalization triggering, and the cell being in a state close to overvoltage for a long time, increasing safety risks.

[0033] Optionally, the first average voltage of a certain battery cell is 3.6V and the highest voltage is 3.8V. The threshold calculated by the formula is (2×3.6+3.8) / 3≈3.67V. This threshold is higher than the average level to avoid frequent triggering of equalization, and lower than the highest voltage to avoid overvoltage hysteresis. It can prepare for equalization in time when the battery cell is close to its own voltage limit but has not reached the safety risk. It's understandable that assigning a 2 / 3 weight to the first average voltage and a 1 / 3 weight to the highest voltage ensures that, during the charging phase, the first average voltage better reflects the overall normal charging voltage level of the cells within the battery pack, serving as a benchmark for determining whether a cell has an abnormally high voltage. The highest voltage, on the other hand, reflects the cell's own voltage limit, preventing the threshold from deviating from the individual characteristics of each cell. The threshold calculation during the charging phase balances both the group benchmark and individual characteristics, using the first average voltage as the primary reference to ensure that the balancing action does not excessively interfere with normally charging cells, reducing unnecessary energy loss and improving charging efficiency. Furthermore, incorporating the highest voltage parameter prevents balancing from failing to trigger even when the cell voltage is close to its own upper limit, reducing the safety risk of overvoltage charging. This design allows the threshold to dynamically adapt to scenarios with rapid voltage changes during the charging phase, improving the accuracy of threshold determination and precisely controlling the timing of balancing triggering.

[0034] It is understandable that this formula eliminates the invalid balancing problem caused by abnormally low-voltage cells. The formula is not sensitive to low-voltage cells and only triggers balancing for cells with truly high voltage, which greatly improves the accuracy of balancing.

[0035] The charging process also includes a resting phase. During the resting phase, the threshold value of the corresponding cell is obtained based on the first average voltage and the highest voltage, using the following formula: V1≥(V2×K1+V3) / K2+V4, where V4 is the preset offset value.

[0036] Optional, the default offset value is 5 millivolts.

[0037] It is understandable that the threshold design during the resting phase achieves precise staged adaptation. By adjusting the threshold through a preset offset value, it avoids misjudgment or missed judgment of the threshold during the resting phase in the charging phase, reduces the impact of erroneous equalization on normal cells, and ensures that potential voltage anomalies can be detected in a timely manner. The flexibility of the preset offset value allows the method to adapt to the resting voltage characteristics of different types of batteries (such as ternary lithium batteries and lithium iron phosphate batteries) or the needs of different resting durations (such as short-term resting and long-term storage), enhancing the versatility of the method, improving the accuracy of threshold determination, and precisely controlling the timing of equalization triggering.

[0038] S203: During the (n+1)th charging process, the voltage of each cell is acquired in real time. When the voltage of a target cell is greater than or equal to a threshold, the first number of times the voltage of the target cell is greater than or equal to the threshold is acquired.

[0039] Before reducing the voltage of the target battery cell, the method also includes: If the voltage of a target cell is greater than or equal to the threshold, the target cell is determined to be a high-voltage cell.

[0040] It is understandable that when the voltage of a target battery cell is greater than or equal to a threshold, the target battery cell is determined to be a high-voltage battery cell. Subsequently, the information of the high-voltage battery cell can be sent to the user, and the user can then decide on the measures to be taken, thereby enhancing the practicality, interactivity and reliability of the method. S204: When the first count is greater than or equal to the first preset count, reduce the voltage of the target cell.

[0041] When the first count is greater than or equal to the first preset count, the voltage of the target cell is reduced, including: When the voltage of a target battery cell is greater than or equal to a threshold, the voltage of the target battery cell is recorded a first number of times within a first preset time period.

[0042] The first preset duration is understood to be a time window for counting the number of cycles, ensuring that the counting focuses on a continuous state within a short period, avoiding delays caused by unlimited time. Triggering is only triggered when a certain number of cycles are reached within this time window, filtering out instantaneous fluctuations. This design provides sufficient time to confirm whether the voltage is continuously high without the risk of overvoltage due to excessively long counting time. The setting of the first preset duration avoids balancing delays caused by unlimited counting, ensuring that high-voltage cells can be processed quickly, reducing damage to the cells from overvoltage conditions and improving safety. Simultaneously, the first preset duration and the first preset number of cycles can be flexibly adjusted according to the charging current and cell type. During high-current charging, the cell voltage rises rapidly, so the duration can be shortened and the number of cycles reduced to avoid overvoltage; during low-current charging, the duration can be extended and the number of cycles increased to filter more fluctuations and enhance the method's adaptability. This design further improves the accuracy and timeliness of balancing triggering.

[0043] Within a first preset time period, the number of times the voltage of the target battery cell is greater than or equal to a threshold includes: At each second preset time interval, the number of times the voltage of the target battery cell is greater than or equal to the threshold is obtained.

[0044] It is understandable that, at each second preset time interval, the number of times the voltage of the target battery cell is greater than or equal to the threshold is obtained. Fixed-interval uniform sampling ensures that the statistical count accurately reflects the voltage state of the battery cell within the first preset time interval, avoiding false or missed triggers caused by sampling deviations and improving the accuracy of balanced triggering. Furthermore, the second preset time interval can be adjusted according to the rate of change of the battery cell voltage (e.g., a shorter interval when the voltage rises rapidly to ensure no critical states are missed; a longer interval when the voltage is stable to reduce hardware resource consumption), enhancing the flexibility of the method and improving the accuracy of obtaining the first count.

[0045] When the first count is greater than or equal to the first preset count, the voltage of the target cell is reduced, which also includes: During the (n+1)th charging process, the second average voltage of multiple cells is acquired in real time. Reduce the voltage of the target cell to the second average voltage.

[0046] It is understandable that the real-time dynamic voltage reduction target design significantly improves the voltage consistency of the battery pack. By reducing the target cell to the current second average voltage, it avoids the ineffective balancing caused by a fixed target, ensuring that all cells in the battery pack are always at a similar voltage level, thus improving the overall charging and discharging efficiency (cells with consistent voltage can work together, preventing some cells from failing to discharge due to excessively low voltage or failing to charge due to excessively high voltage). Simultaneously, real-time acquisition of the second average voltage allows the balancing target to adapt to voltage changes during the charging process. Furthermore, improved voltage consistency reduces circulating current losses between cells, lowers the overall energy loss of the battery pack, and extends cell cycle life. This design effectively maintains long-term consistency between cells, ensuring the long-term performance stability of the battery pack.

[0047] Reducing the voltage of the target battery cell to the second average voltage includes: The target battery cell is controlled to discharge and equalize to a first voltage using a first equalizing current, and the first voltage is greater than a second average voltage. The target cell is controlled to discharge from the first voltage to the second average voltage using a second equalizing current, where the second equalizing current is less than the first equalizing current.

[0048] The first stage, rapid voltage reduction with high current, significantly shortens the overvoltage time of the target cell, reducing damage caused by overvoltage (such as electrolyte decomposition and electrode material detachment), improving safety, and shortening balancing time without affecting overall charging efficiency. The second stage, precise voltage control with low current, avoids imbalances caused by voltage overshoot, ensuring a perfect match between the target cell voltage and the second average voltage, maintaining battery pack voltage consistency. Furthermore, low-current discharge has less impact on the cell, reducing polarization effects during discharge, lowering the risk of internal temperature rise, further protecting the cell structure, and extending cycle life. This design meets the demands of fast charging while ensuring accurate balancing and cell safety, improving the overall performance of the battery pack. In the existing technology, please refer to Figure 4 , Figure 5 and Figure 6Existing strategies only activate passive balancing technology at the end of the charging process. However, the optimized strategy of this application can activate passive balancing technology throughout the entire charging process, solving the problem of a short balancing time window during charging. This extends the balancing time to the entire charging cycle, providing sufficient working time for the balancing process and improving the efficiency of passive balancing. Specifically, in existing strategies, balancing is only activated at the end of the charging process (>3.4V). During charging, in the plateau region below 3.4V, a small voltage difference (e.g., 10mV) between cells may correspond to a significant difference in state of charge (potentially 5%-10%). If balancing is activated at this time, the battery management system cannot accurately determine which cell truly has "more charge" and which has "less charge but a higher voltage measurement." Voltage-based balancing in the plateau region is likely to become increasingly inaccurate and may even exacerbate cell inconsistencies. When the voltage is above 3.4V (entering the non-plateau region), the correspondence between voltage and state of charge becomes clearer. At this time, cells with higher voltage can be determined to have a higher state of charge, making balancing (discharging high-voltage cells) accurate. For example, taking a first preset power and one charge and one discharge per day as an example, the existing passive balancing strategy is activated for 1 hour during the charging process. In the lithium battery energy storage system operation scenario, the cutoff voltage during the charging process is generally set to 3.55-3.6V, and the charging time from 3.4V to 3.6V is about 1 hour. However, by extending the balancing time to 2.5 hours for the entire charging process, the passive balancing efficiency can be improved by 1.13 times. In the first preset power operation system, considering the end power reduction strategy, the entire charging process takes about 2.5 hours.

[0049] It is understandable that determining the threshold based on the actual voltage data of the cell's previous (nth) charge (the first average voltage reflects the cell's normal charging state, and the highest voltage reflects its voltage upper limit characteristic) deeply binds the threshold to the cell's own historical charging characteristics (which have historical voltage memory function), rather than a fixed value detached from reality. This allows for dynamic adaptation to changes in the cell's state, avoiding the adaptability defects of fixed thresholds, reducing ineffective cell equalization, and lowering energy loss and heat generation. Introducing a trigger condition where the first count is greater than or equal to the first preset count requires confirmation of voltage exceeding the limit through multiple monitoring sessions, rather than a single trigger. This effectively filters interference from instantaneous voltage fluctuations, ensuring that the cell triggering equalization is indeed in a continuously high voltage state. This method significantly improves the accuracy and reliability of equalization triggering. The adaptive threshold design allows the equalization action to accurately match the actual state of the cell, avoiding cell overvoltage damage caused by missed equalization or energy loss caused by incorrect equalization. The multiple confirmation mechanism reduces the impact of instantaneous fluctuations, protecting normal cells from unnecessary voltage reduction operations and extending cell cycle life. Meanwhile, by continuously handling high-voltage cells throughout the charging process, the voltage consistency of cells within the battery pack can be effectively maintained, preventing overvoltage of a single cell from affecting the charging and discharging efficiency and safety of the entire battery pack, and improving the overall performance stability of the battery pack. Please see Figure 3 , Figure 3 This is a schematic diagram of the structure of an equalization device 103 provided in an embodiment of this application, including a processor 301, a memory 302, and at least one program 303, wherein at least one program 303 is stored in the memory 302 and configured to be executed by the processor 301, and the program 303 includes instructions for performing the following steps: Obtain the voltage data of each cell during the nth charging process, where n≥1. The voltage data of each cell during the nth charging process includes the first average voltage and the highest voltage. The threshold of the corresponding cell is obtained based on the first average voltage and the highest voltage; During the (n+1)th charging process, the voltage of each cell is acquired in real time. When the voltage of a target cell is greater than or equal to a threshold, the first number of times the voltage of the target cell is greater than or equal to the threshold is acquired. When the first count is greater than or equal to the first preset count, the voltage of the target cell is reduced.

[0050] In one possible example, the charging process includes a charging phase, during which program 303 specifically executes instructions for the following steps: V1≥(V2×2+V3) / 3, where V1 is the threshold, V2 is the first average voltage, and V3 is the highest voltage.

[0051] In one possible example, the charging process also includes a resting phase, during which program 303 specifically executes instructions for the following steps: V1≥(V2×2+V3) / 3+V4, where V4 is the preset offset value.

[0052] In one possible example, program 303 is specifically used to perform the following instructions: If the voltage of a target cell is greater than or equal to the threshold, the target cell is determined to be a high-voltage cell.

[0053] In one possible example, program 303 is specifically used to perform the following instructions: When the voltage of a target battery cell is greater than or equal to a threshold, the voltage of the target battery cell is recorded a first number of times within a first preset time period.

[0054] In one possible example, program 303 is specifically used to perform the following instructions: At each second preset time interval, the number of times the voltage of the target battery cell is greater than or equal to the threshold is obtained.

[0055] In one possible example, program 303 is specifically used to perform the following instructions: During the (n+1)th charging process, the second average voltage of multiple cells is acquired in real time. Reduce the voltage of the target cell to the second average voltage.

[0056] In one possible example, program 303 is specifically used to perform the following instructions: The target battery cell is controlled to discharge and equalize to a first voltage using a first equalizing current, and the first voltage is greater than a second average voltage. The target cell is controlled to discharge from the first voltage to the second average voltage using a second equalizing current, where the second equalizing current is less than the first equalizing current.

[0057] Those skilled in the art will understand that, for ease of explanation, Figure 3 Only one memory 302 and processor 301 are shown in the illustration. In a real terminal or server, multiple processors 301 and memory 302 may exist. The memory 302 may also be referred to as a storage medium or storage device, etc., and this embodiment does not impose any limitations on this.

[0058] It should be understood that in this application, the processor 301 may be a central processing unit (CPU), or it may be other general-purpose processors 301, digital signal processors 301 (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The processor 301 may also be a general-purpose microprocessor 301, a graphics processing unit (GPU), or one or more integrated circuits to execute the relevant program 303 to achieve the functions required by the embodiments of this application.

[0059] The processor 301 can also be an integrated circuit chip with signal processing capabilities. In implementation, each step of this application can be completed through integrated logic circuits in the hardware of the processor 301 or through software instructions. The processor 301 described above can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The steps of the methods disclosed in the embodiments of this application can be directly manifested as being executed by the hardware decoding processor 301, or executed by a combination of hardware and software modules in the decoding processor 301. The software modules can be located in random access memory 302, flash memory and read-only memory 302, programmable read-only memory 302 or electrically erasable programmable memory 302, registers, and other mature storage media in the art. The storage medium is located in memory 302, and the processor 301 reads the information in memory 302 and, in conjunction with its hardware, completes the functions required by the units included in the methods, apparatus, and storage media of the embodiments of this application.

[0060] It should also be understood that the memory 302 mentioned in the embodiments of this application can be volatile memory 302 or non-volatile memory 302, or may include both volatile and non-volatile memory 302. The non-volatile memory 302 can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. The volatile memory 302 can be random access memory (RAM), which is used as an external cache. By way of example, but not limitation, many forms of RAM are available, such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDR SDRAM), Enhanced Synchronous DRAM (ESDRAM), Synchlink DRAM (SLDRAM), and Direct Rambus RAM (DR RAM). The memory 302 can also be a Compact Disc Read-Only Memory (CD-ROM) or other optical disc storage, optical disk storage (including compressed optical disks, laser discs, optical discs, digital universal optical discs, Blu-ray discs, etc.), magnetic disk storage media, or other magnetic storage devices, or any other medium capable of carrying or storing the desired program 303 code in the form of instructions or data structures and accessible by a computer, but is not limited thereto. The memory 302 can exist independently and be connected to the processor 301 via a bus. The memory 302 can also be integrated with the processor 301. The memory 302 can store the program 303, and when the program 303 stored in the memory 302 is executed by the processor 301, the processor 301 performs the various steps of the method determined in the above embodiments of this application.

[0061] It should be noted that when the processor 301 is a general-purpose processor 301, DSP, ASIC, FPGA, or other programmable logic device, discrete gate or transistor logic device, or discrete hardware component, the memory 302 (memory module) is integrated into the processor 301. It should be noted that the memory 302 described herein is intended to include, but is not limited to, these and any other suitable types of memory 302.

[0062] It should be understood that the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0063] In implementation, each step of the above method can be completed by the integrated logic circuitry of the hardware in the processor 301 or by instructions in software form. The steps of the method disclosed in the embodiments of this application can be directly manifested as execution by the hardware processor 301, or execution by a combination of hardware and software modules in the processor 301. The software modules can reside in mature storage media in the art, such as random access memory 302, flash memory, read-only memory 302, programmable read-only memory 302, electrically erasable programmable memory 302, registers, etc. This storage medium is located in memory 302. The processor 301 reads information from memory 302 and, in conjunction with its hardware, completes the steps of the above method. To avoid repetition, these will not be described in detail here.

[0064] Those skilled in the art will recognize that the various illustrative logical blocks (ILBs) and steps described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this application.

[0065] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented entirely or partially as a computer-programmed program 303 product. The program 303 product includes one or more computer instructions. When the program 303 instructions are loaded and executed on the processor 301, all or part of the flow or function according to the embodiments of this application is generated. The computer can be a general-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic) or wireless (e.g., infrared, wireless, microwave, etc.) means, or from one website, computer, server, or data center to the mobile phone processor 301 via a wired means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available media can be magnetic media (e.g., floppy disks, hard disks), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state drives).

[0066] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. An equilibrium method, characterized in that, The balancing method is applied to a battery pack, the battery pack comprising multiple battery cells, and the balancing method includes: Obtain the voltage data of each of the battery cells during the nth charging process, where n≥1, and the voltage data of each of the battery cells during the nth charging process includes a first average voltage and a maximum voltage; The threshold value corresponding to the battery cell is obtained based on the first average voltage and the highest voltage; During the (n+1)th charging process, the voltage of each of the cells is acquired in real time. When the voltage of a target cell is greater than or equal to the threshold, the first number of times the voltage of the target cell is greater than or equal to the threshold is acquired. When the first number of times is greater than or equal to the first preset number of times, the voltage of the target battery cell is reduced.

2. The equalization method according to claim 1, characterized in that, The charging process includes a charging phase. When the battery pack is in the charging phase, the threshold value corresponding to the battery cell is obtained based on the first average voltage and the highest voltage using the following formula: V1≥(V2×K1+V3) / K2, where V1 is the threshold, K1 is a preset first coefficient, K2 is a preset second coefficient, V2 is the first average voltage, and V3 is the highest voltage.

3. The balancing method according to claim 2, characterized in that, The charging process also includes a resting phase. When the battery pack is in the resting phase, the threshold value corresponding to the battery cell is obtained based on the first average voltage and the highest voltage using the following formula: V1≥(V2×K1+V3) / K2+V4, where V4 is a preset offset value.

4. The balancing method according to any one of claims 1 to 3, characterized in that, Before reducing the voltage of the target battery cell, the method further includes: When there is a target cell whose voltage is greater than or equal to the threshold, the target cell is determined to be a high-voltage cell.

5. The balancing method according to any one of claims 1 to 3, characterized in that, The step of reducing the voltage of the target battery cell when the first number of times is greater than or equal to the first preset number of times includes: When the voltage of a target battery cell is greater than or equal to the threshold, the voltage of the target battery cell is obtained a first number of times within a first preset time period.

6. The equalization method according to claim 5, characterized in that, The first number of times within a first preset time period that the voltage of the target battery cell is greater than or equal to the threshold includes: At each second preset time interval, the voltage of the target battery cell is obtained a first number of times that is greater than or equal to the threshold.

7. The balancing method according to any one of claims 1 to 3, characterized in that, The step of reducing the voltage of the target battery cell when the first number of times is greater than or equal to the first preset number of times further includes: During the (n+1)th charging process, the second average voltage of the multiple battery cells is acquired in real time. The voltage of the target cell is reduced to the second average voltage.

8. The balancing method according to claim 7, characterized in that, The step of reducing the voltage of the target battery cell to the second average voltage includes: The target battery cell is controlled to discharge and equalize to a first voltage using a first equalizing current, wherein the first voltage is greater than the second average voltage. The target cell is controlled to discharge from the first voltage to the second average voltage using a second equalizing current, wherein the second equalizing current is less than the first equalizing current.

9. A leveling device, characterized in that, The method includes a processor, a memory, and at least one program, wherein the at least one program is stored in the memory and configured to be executed by the processor, the program including instructions for performing the method of any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that causes a computer to perform the method according to any one of claims 1 to 8.

Images