Parallel control method and electronic equipment for multiple battery packs

Abstract

This application belongs to the field of parallel control technology, and relates to a method and electronic device for parallel control of multiple battery packs. By collecting the open-circuit voltage of each battery pack and determining whether to fully open the diodes or process them in groups, dynamic parallel control decision-making based on battery status is achieved. This allows the system to automatically select the coordination mode according to the voltage difference, improving the stability of power supply from multiple battery packs. Secondly, by designing the wires from each battery pack to the bus to be of equal length, the uneven current distribution caused by differences in line resistance is reduced, resulting in a more balanced charging and discharging load, improving system efficiency and battery pack life. Thus, this application can simultaneously solve the problems of insufficient dynamic parallel control decision-making and uneven line resistance, significantly improving system performance and adaptability.

Description

Technical Field

[0001] This application belongs to the field of parallel control technology, specifically relating to a method and electronic device for parallel control of multiple battery packs. Background Technology

[0002] As the application scenarios for portable electronic devices continue to expand, these devices are increasingly demanding higher capacity and longer battery life. However, due to limitations such as size, weight, and portability, the capacity and output capability of a single power module (battery pack) cannot be increased indefinitely. Therefore, capacity expansion is usually achieved by connecting multiple battery packs in parallel to the system, allowing users to flexibly increase battery life according to their actual needs.

[0003] Current battery pack systems in electronic devices typically employ a single battery pack as the primary output after power-on, with downstream circuits controlling the current of other battery packs to achieve voltage convergence and parallel operation. While this approach can achieve collaborative power supply from multiple battery packs to some extent, as the power of terminal devices continues to increase, the limitations of relying solely on a single battery pack for primary output are becoming increasingly apparent. For example, under high-power loads, the output of a single pack may approach the protection threshold, leading to unstable power supply. Furthermore, in scenarios with external energy inputs such as photovoltaics, the limited energy absorption capacity of the battery packs may result in the ineffective storage of usable energy.

[0004] In the process of developing this application, the inventors discovered at least the following problems in the prior art: First, current systems generally lack a multi-dimensional evaluation mechanism based on battery state, making it impossible to fully analyze the operating state of multiple battery packs, thus making it difficult to achieve a more reasonable battery pack coordination method under different operating modes. Second, since the connection conditions between battery packs are not entirely consistent, factors such as wire length and connection structure may introduce differences, thereby affecting current distribution and energy flow, which in turn affects the overall system efficiency. Summary of the Invention

[0005] To address the aforementioned issues, this application provides a method and electronic device for parallel control of multiple battery packs, which optimizes the control logic for the coordinated operation of multiple battery packs to achieve stable power supply, reasonable energy distribution, and continuous and reliable operation of the system under different operating conditions.

[0006] To solve the above-mentioned technical problems, one technical solution adopted in this application is: providing a multi-battery pack parallel control method, applied to a parallel battery pack system, the parallel battery pack system including multiple battery packs, the positive and negative terminals of the multiple battery packs being connected to a positive and negative bus via wires, the positive and negative bus being connected to an inverter, wherein the length of the wires from each battery pack to the positive and negative bus is equal, the method including: obtaining the open-circuit voltage of each battery pack, and obtaining a target voltage difference based on the open-circuit voltage; when the target voltage difference meets a preset full-open-tube parallel charging condition, selecting the battery pack with the largest open-circuit voltage as the master battery pack, and determining the open-tube battery pack based on the master battery pack; when the target voltage difference does not meet the full-open-tube parallel charging condition, grouping the battery packs to obtain grouped battery pack groups, and selecting the battery pack group with the largest target current as the target battery pack group based on the battery pack groups; determining the open-tube battery pack based on the target battery pack groups, and selecting the battery pack with the smallest open-circuit voltage in the target battery pack group as the master battery pack.

[0007] In some embodiments, obtaining the open-circuit voltage of each battery pack and obtaining a target voltage difference based on the open-circuit voltage includes: obtaining the open-circuit voltage of each battery pack; sorting the open-circuit voltages to obtain sorted battery packs, and determining the maximum value among the open-circuit voltages as the first open-circuit voltage and the minimum value among the open-circuit voltages as the second open-circuit voltage; and obtaining the target voltage difference based on the first open-circuit voltage and the second open-circuit voltage.

[0008] In some embodiments, when the target voltage difference meets the preset fully open-circuit battery pack condition, the battery pack with the largest open-circuit voltage is selected as the main battery pack, and the open-circuit battery pack is determined based on the main battery pack, including: judging the target voltage difference; if the target voltage difference is not greater than the open-circuit threshold, the battery pack corresponding to the first open-circuit voltage is selected as the main battery pack, and the battery packs corresponding to the second open-circuit voltage are determined as open-circuit battery packs based on the main battery pack; wherein, the open-circuit threshold is calculated by the maximum allowable charging current of the battery pack corresponding to the second open-circuit voltage and the internal resistance of the battery pack corresponding to the second open-circuit voltage.

[0009] In some embodiments, the activation state of the battery pack system includes a button activation state, the target current includes the maximum allowable total discharge current, and when the target voltage difference does not meet the fully open diode paralleling condition, the battery packs are grouped to obtain grouped battery pack groups, and the battery pack group with the largest target current is selected as the target battery pack group. This includes: when the target voltage difference does not meet the fully open diode paralleling condition and the activation state is a button activation state, grouping each battery pack according to the open-circuit voltage and open diode threshold of each sorted battery pack to obtain grouped battery pack groups; calculating the maximum allowable total discharge current of each group of battery packs; and selecting the battery pack group with the largest maximum allowable total discharge current as the target battery pack group.

[0010] In some embodiments, determining an open-circuit battery pack based on a target battery pack group and selecting the battery pack with the smallest open-circuit voltage in the target battery pack group as the master battery pack includes: when the number of target battery pack groups is one, determining that the battery packs in the target battery pack group are open-circuit battery packs and selecting the battery pack with the smallest open-circuit voltage in the target battery pack group as the master battery pack; when the number of target battery pack groups is multiple, selecting the battery packs in the target battery pack group with the largest average voltage as open-circuit battery packs and selecting the battery pack with the smallest open-circuit voltage in the target battery pack group with the largest average voltage as the master battery pack.

[0011] In some embodiments, the activation state of the battery pack system includes a photovoltaic / grid activation state, and the target current includes the maximum allowable total charging current. When the target voltage difference does not meet the fully open-circuit battery pack activation condition, the battery packs are grouped to obtain grouped battery pack groups. Based on the battery pack groups, the battery pack group with the largest target current is selected as the target battery pack group. This includes: when the target voltage difference does not meet the fully open-circuit battery pack activation condition and the activation state is a photovoltaic / grid activation state, grouping each battery pack according to the open-circuit voltage and open-circuit threshold of each sorted battery pack to obtain grouped battery pack groups; calculating the maximum allowable total charging current of each group of battery packs; and selecting the battery pack group with the largest maximum allowable total charging current as the target battery pack group.

[0012] In some embodiments, determining an open-circuit battery pack based on a target battery pack group and selecting the battery pack with the smallest open-circuit voltage in the target battery pack group as the master battery pack includes: when the number of target battery pack groups is one, determining that the battery packs in the target battery pack group are open-circuit battery packs and selecting the battery pack with the smallest open-circuit voltage in the target battery pack group as the master battery pack; when the number of target battery pack groups is multiple, selecting the battery packs in the target battery pack group with the smallest average voltage as open-circuit battery packs and selecting the battery pack with the smallest open-circuit voltage in the target battery pack group with the smallest average voltage as the master battery pack.

[0013] In some embodiments, the method further includes: when a battery pack is hot-swapped, determining whether the hot-swapped battery pack is a host battery pack; when the hot-swapped battery pack is a host battery pack, determining the host battery pack based on a first hot-swapping strategy; when the hot-swapped battery pack is not a host battery pack, determining the open-tube battery pack based on a second hot-swapping strategy.

[0014] In some embodiments, when the hot-swappable battery pack is a host battery pack, determining the host battery pack based on a first hot-swappable strategy includes: when the hot-swappable battery pack is a host battery pack, determining whether all open-circuit battery packs in the target battery pack group where the host battery pack is located have been disconnected; if all open-circuit battery packs in the target battery pack group where the host battery pack is located have been disconnected, determining the current state of the battery pack system; if the current state is a discharging state, selecting the battery pack with the largest open-circuit voltage as the host battery pack; if the current state is a charging state, selecting the battery pack with the smallest open-circuit voltage as the host battery pack; if not all open-circuit battery packs in the target battery pack group where the host battery pack is located have been disconnected, selecting the battery pack with the smallest open-circuit voltage among the open-circuit battery packs in the target battery pack group where the host battery pack is located as the host battery pack.

[0015] In some embodiments, when the hot-swapped battery pack is not the main battery pack, determining the open-circuit battery pack based on the second hot-swappable strategy includes: when the hot-swapped battery pack is not the main battery pack, updating the maximum allowable total charging current and the maximum allowable total discharging current of the parallel battery pack system, and determining the current state of the parallel battery pack system; when the current state is charging, obtaining the current charging current of the parallel battery pack system; when the maximum allowable total charging current is less than the current charging current, performing open-circuit and parallel processing from the non-open-circuit battery pack with the smallest open-circuit voltage until the maximum allowable total charging current is not less than the current charging current; when the current state is discharging, obtaining the current discharging current of the parallel battery pack system; when the maximum allowable total discharging current is less than the current discharging current, performing open-circuit and parallel processing from the non-open-circuit battery pack with the largest open-circuit voltage until the maximum allowable total discharging current is not less than the current discharging current.

[0016] To solve the above-mentioned technical problems, another technical solution adopted in the embodiments of this application is: to provide an electronic device, including: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the above-mentioned method.

[0017] Unlike related technologies, this application provides a method and electronic device for parallel control of multiple battery packs. By collecting the open-circuit voltage of each battery pack and using this to determine the fully open transistor condition or group processing, dynamic parallel control decision-making based on the real-time battery status is achieved. This allows the system to automatically select the optimal coordination mode based on different voltage differences, improving the overall stability when multiple battery packs participate in power supply. Secondly, by designing the wires from each battery pack to the bus to be of equal length, the impact of line resistance differences on current distribution can be effectively reduced, making the load of different battery packs more balanced during charging and discharging, thereby improving system efficiency and the service life of each battery pack. Based on this, this application can simultaneously solve the problems of insufficient dynamic parallel control decision-making and current distribution imbalance caused by uneven line resistance in the prior art, significantly improving the overall performance and operational adaptability of the parallel control system. Attached Figure Description

[0018] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0019] Figure 1 This is a schematic diagram of the structure of a packaging system provided in an embodiment of this application;

[0020] Figure 2 This is a flowchart of a multi-battery pack parallel control method provided in an embodiment of this application;

[0021] Figure 3 This is a schematic diagram illustrating the determination of the host battery pack and the open-tube battery pack when the conditions for full open-tube packaging are met, according to an embodiment of this application.

[0022] Figure 4 This is a schematic diagram illustrating the determination of the host battery pack and the open-tube battery pack when the conditions for full open-tube packaging are not met and the number of target battery pack groups is one group, as provided in an embodiment of this application.

[0023] Figure 5 This is a schematic diagram illustrating the determination of the host battery pack and the open-tube battery pack when the conditions for full open-tube packaging are not met and the number of target battery pack groups is multiple.

[0024] Figure 6 This is a schematic diagram of determining the host battery pack and the open-tube battery pack when the fully open-tube packaging condition is not met and the number of target battery pack groups is multiple;

[0025] Figure 7 This is a schematic diagram illustrating how a hot-swappable battery pack is a host battery pack that is constantly being determined by the host battery pack, according to an embodiment of this application.

[0026] Figure 8 This is a schematic diagram of the hardware structure of an electronic device that performs a multi-battery pack parallel control method according to an embodiment of this application. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and thoroughly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0028] It should be noted that, unless otherwise specified, the various features in the embodiments of this application can be combined with each other, all of which are within the protection scope of this application. When an element is described as "connected" to another element, it can be directly connected to the other element, or there may be one or more intervening elements between them.

[0029] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, the character " / " in the specification and claims generally indicates that the preceding and following objects are in an "or" relationship.

[0030] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application.

[0031] Please see Figure 1 , Figure 1 This is a schematic diagram of the structure of a packaging system provided in an embodiment of this application. For example... Figure 1 As shown, the battery pack system 10 includes multiple battery packs. The positive terminal of each battery pack is connected to the positive bus, and the negative terminal is connected to the negative bus. The positive and negative buses are electrically connected to the inverter 20.

[0032] Each battery pack contains a bidirectional Buck module and a main MOSFET switch. The bidirectional Buck module is used for current limiting control during pre-charge and pre-discharge. The pre-charge function limits the current entering the battery pack from external input, while the pre-discharge function limits the discharge current from the battery pack to the outside, allowing each individual battery pack to independently complete the voltage leveling and soft-start process. The main MOSFET switch is used for high-current on / off control, enabling the battery pack to directly participate in the system's charging and discharging with a large current when the parallel charging conditions are met.

[0033] Each battery pack possesses autonomous master-slave negotiation capabilities, exchanging status data and determining the master battery pack via a communication link. The master battery pack is responsible for unified processing of system information, sending data externally, receiving external commands, and issuing control parameters to the slave battery packs. The slave battery packs execute corresponding current limiting, power on / off operations based on the configuration issued by the master. Based on this structure, each battery pack can switch master / slave roles according to status changes during use, and hot-swapping is supported. Protection and alarm mechanisms are triggered when a plugging / unplugging event occurs to ensure system operational safety.

[0034] After the system is powered on, each battery pack automatically completes grouping processing based on communication data to identify battery packs with higher charging and discharging capabilities under the current voltage difference conditions. The system prioritizes putting these battery packs into main circuit operation to ensure that they can output or absorb the maximum available current during the power-on phase. When the load current is small after power-on or there is a large voltage difference between battery packs, the remaining battery packs can gradually level out their voltage through the bidirectional Buck module in a current-limiting manner until the switching conditions are met and they can be directly connected to the main circuit operation.

[0035] Furthermore, in a multi-battery pack parallel structure, when the battery pack is charged by an external power source, the charging power supply voltage can be expressed as:

[0036] (1);

[0037] The voltage of battery pack 1 can be expressed as:

[0038] (2);

[0039] Where R is the internal resistance of the battery pack. The line resistance from it to the bus, This represents the charging current of battery pack 1.

[0040] Therefore, it can be concluded that, assuming all battery packs have the same internal resistance, if the corresponding line resistances of different battery packs are different... Inconsistencies can lead to inconsistent absorption or output currents among battery packs during parallel operation due to differences in line resistance voltage division. Uneven current distribution can cause some battery packs to charge or discharge prematurely, preventing them from continuing to participate in charging and discharging, and can also limit the overall input and output capabilities of the system. In this embodiment, to ensure balanced current distribution among multiple battery packs during charging and discharging, the wire lengths from each battery pack to the positive and negative terminals are designed to be equal. This minimizes the current distribution differences caused by line resistance deviations, ensures the consistency of electrical characteristics of multiple battery packs during parallel operation, and thus improves the stability and effectiveness of the parallel operation process.

[0041] The implementation process of the multi-battery pack parallel control method provided in this application embodiment will be described in detail below with reference to specific embodiments.

[0042] Please see Figure 2 , Figure 2 This is a flowchart illustrating a multi-battery pack parallel control method provided in an embodiment of this application. The method is applied to the aforementioned parallel pack system 10. Figure 2 As shown, the method includes steps S11-S14:

[0043] S11: Obtain the open-circuit voltage of each battery pack, and obtain the target voltage difference based on the open-circuit voltage.

[0044] The process of obtaining the open-circuit voltage of each battery pack and obtaining the target voltage difference based on the open-circuit voltage includes: obtaining the open-circuit voltage of each battery pack; sorting the open-circuit voltages to obtain the sorted battery packs, and determining the maximum value among the open-circuit voltages as the first open-circuit voltage and the minimum value among the open-circuit voltages as the second open-circuit voltage; and obtaining the target voltage difference based on the first open-circuit voltage and the second open-circuit voltage.

[0045] After the system powers on and establishes communication, it broadcasts sampling requests to all battery packs or periodically reports sampling data from each battery pack. Each battery pack measures and reports status variables including, but not limited to, open-circuit voltage, battery temperature, and SOC.

[0046] After receiving open-circuit voltage data from each battery pack, the system first performs a validity check on each data stream (e.g., checking communication integrity, values ​​outside the physical range, sampling timing conflicts, etc.). For battery packs with communication packet loss or measurement anomalies, the last valid value can be used or the data can be marked for retesting until valid data is obtained.

[0047] Subsequently, the battery packs that passed the validity check were sorted from highest to lowest according to their open-circuit voltage, resulting in an ordered sequence. ,in The battery pack with the highest open-circuit voltage is denoted as . (First open-circuit voltage); The battery pack with the lowest open-circuit voltage is denoted as . (Second open-circuit voltage). Here, k is the total number of battery packs that are effectively connected and participating in the determination in the current system. To maintain index stability, the original identifier of each pack (e.g., pack address or serial number) is retained after sorting.

[0048] Based on the sorting results, the target voltage difference is calculated as follows:

[0049] (3);

[0050] in, The target voltage difference used as the basis for subsequent judgment of the co-containment conditions (such as the co-containment conditions of fully open tubes).

[0051] Finally, sort the battery packs into a list and their corresponding... , and the calculated Write to the register and trigger the next control logic (such as entering the packet condition judgment in S12), and archive the sampling timestamp and the original measurement values ​​of each packet for fault tracking and strategy adjustment.

[0052] Optionally, if valid open-circuit voltage data for each battery pack cannot be obtained due to communication or measurement anomalies, the system enters a safety mode: maintaining the current open-circuit configuration or placing all packs in current-limiting mode and retrying sampling until the data integrity requirements are met.

[0053] By uniformly executing data sampling broadcasts or receiving periodic reports from each battery pack after the system is powered on, and combining communication validity verification and fault-tolerant handling strategies for abnormal packets, step S11 ensures that the key state quantities such as open-circuit voltage, temperature, and SOC acquired by the system are accurate and reliable, thus avoiding erroneous packet judgments caused by measurement errors or communication interruptions from the source. Furthermore, by sorting the valid battery packs by open-circuit voltage and calculating the target voltage difference... The system can obtain core indicators reflecting the overall voltage distribution of multiple battery packs, providing accurate basis for subsequent judgment of fully open diodes in parallel operation, grouping strategies, and host selection. Furthermore, by recording sampled values ​​and timestamps, fault tracing and strategy optimization can be supported, making the parallel operation control process verifiable and adjustable.

[0054] S12: When the target voltage difference meets the preset full open tube parallel package condition, select the battery pack with the largest open circuit voltage as the main battery pack, and determine the open tube battery pack based on the main battery pack.

[0055] Specifically, when the target voltage difference meets the preset fully open-circuit battery pack condition, the battery pack with the largest open-circuit voltage is selected as the main battery pack, and the open-circuit battery pack is determined based on the main battery pack. This includes: judging the target voltage difference; if the target voltage difference is not greater than the open-circuit threshold, the battery pack corresponding to the first open-circuit voltage is selected as the main battery pack, and based on the main battery pack, the battery packs corresponding to the second open-circuit voltage are determined as open-circuit battery packs; wherein, the open-circuit threshold is calculated by the maximum allowable charging current of the battery pack corresponding to the second open-circuit voltage and the internal resistance of the battery pack corresponding to the second open-circuit voltage.

[0056] The system compares the target voltage difference ΔU calculated by S11 with the tube-opening threshold. The tube-opening threshold is determined by the battery pack with the lowest voltage in the system (i.e., the one in the sorted sequence). Maximum allowable charging current Its internal resistance The calculation formula is as follows:

[0057] (4);

[0058] in, The maximum allowable charging current for battery pack k is the minimum value under both SOC and temperature limits.

[0059] (5);

[0060] in, This represents the maximum safe charging current for battery pack k, considering only the current SOC (State of Charge) conditions. This represents the maximum safe charging current for battery pack k, considering only the current temperature conditions. This indicates the current battery health status value of battery pack k.

[0061] When the judgment result shows Less than or equal to the opening threshold At this time, the system assumes that all battery packs meet the conditions for fully open tubes and parallel packs. At this point, if... Figure 3 As shown, the system selects the battery pack with the highest open-circuit voltage. As the main battery pack, it is responsible for overall control and communication with external systems. Simultaneously, the system operates based on the main battery pack... Determine the range of open-tube battery packs, i.e., from the main battery pack to the battery pack with the lowest voltage. All battery packs between (including main battery pack and battery pack) All MOSFETs are turned on simultaneously. Through this operation, the high-voltage battery pack will charge the low-voltage battery pack, achieving voltage leveling, thereby ensuring that the entire system can directly connect to all battery packs and provide maximum output or absorption capacity when powered on.

[0062] During this process, the system records the host battery pack identifier and the information of the open-tube battery pack group for use in subsequent steps (such as grouping processing in S13 and S14 or hot-swapping processing). In addition, this strategy can ensure that the battery packs work together at the moment of power-on, so as to balance the output current distribution of the multi-battery pack system, avoid protection actions caused by excessive load on a single pack, and improve the overall load-carrying or charging and discharging capacity of the system.

[0063] In step S12, by acquiring the open-circuit voltage of each battery pack in real time and calculating the target voltage difference, the system compares this value with the MOSFET threshold calculated based on the maximum allowable charging current and internal resistance of the battery pack with the lowest voltage. The system can intelligently determine whether the conditions for full MOSFET connection are met. When the conditions are met, the system automatically selects the battery pack with the highest open-circuit voltage as the master battery pack and simultaneously turns on the MOSFETs of all battery packs from the master pack to the lowest voltage battery pack. This achieves voltage leveling by charging the higher-voltage pack to the lower-voltage pack, ensuring that the multi-battery pack system can quickly and evenly connect and provide maximum output or absorption capacity at power-on. This not only improves the current distribution balance and overall stability of the system during the connection phase but also effectively avoids protection actions caused by excessive load on a single battery pack, improving the safety, reliability, and load-bearing or charging / discharging efficiency of the multi-battery pack parallel system.

[0064] S13: When the target voltage difference does not meet the fully open tube parallel pack condition, the battery packs are grouped to obtain the grouped battery pack groups, and the battery pack group with the largest target current is selected as the target battery pack group according to the battery pack groups.

[0065] S14: Based on the target battery pack group, determine the open-circuit battery pack and select the battery pack with the smallest open-circuit voltage in the target battery pack group as the main battery pack.

[0066] The activation state of the battery pack system includes a button activation state, and the target current includes the maximum allowable total discharge current. When the target voltage difference does not meet the fully open transistor connection condition, the battery packs are grouped to obtain grouped battery pack groups. Based on the battery pack groups, the battery pack group with the largest target current is selected as the target battery pack group. This includes: when the target voltage difference does not meet the fully open transistor connection condition and the activation state is button activation state, the battery packs are grouped according to the open-circuit voltage and open transistor threshold of each sorted battery pack to obtain grouped battery pack groups; the maximum allowable total discharge current of each group of battery packs is calculated; and the battery pack group with the largest maximum allowable total discharge current is selected as the target battery pack group.

[0067] Specifically, based on the target battery pack group, the open-circuit battery pack is determined, and the battery pack with the smallest open-circuit voltage in the target battery pack group is selected as the main battery pack. This includes: when there is only one target battery pack group, the battery packs in the target battery pack group are determined to be open-circuit battery packs, and the battery pack with the smallest open-circuit voltage in the target battery pack group is selected as the main battery pack; when there are multiple target battery pack groups, the battery packs in the target battery pack group with the largest average voltage are selected as open-circuit battery packs, and the battery pack with the smallest open-circuit voltage in the target battery pack group with the largest average voltage is selected as the main battery pack.

[0068] When the target voltage difference calculated after system power-on does not meet the preset fully open diode paralleling condition, and the system is in button-activated state (at which time the default is discharge mode), the system will group the battery packs to ensure that current distribution is balanced and system safety and output capacity are maximized even when fully open diode paralleling is not possible. The specific implementation process is as follows:

[0069] The system, based on the list of battery packs sorted by open-circuit voltage obtained in step S11 and the open-circuit threshold, sequentially performs group statistics on each battery pack. For the sorted battery pack i, the system counts those with a voltage higher than battery pack i and a voltage difference between them that of battery pack i and battery pack i within a certain range. Number of battery packs within the range (Excluding battery pack i itself), and these battery packs together with battery pack i form a battery pack group. In this way, each battery pack and its safe-to-combine high-voltage neighboring packs form a separate battery pack group.

[0070] For each group The system takes the discharge SOP of the battery pack with the lowest voltage in the group and multiplies it by the number of battery packs in the group. +1), to obtain the maximum allowable total discharge current of this group. The calculation formula is as follows:

[0071] (6);

[0072] in, This represents the SOP (Start of Production) value of the battery pack (i-Ni) based on SOC (State of Charge) limitations, where i is the value of the battery pack. The highest serial number of the battery pack in the group. The number of battery packs after excluding battery pack i is given; battery pack (i-Ni) is... The smallest number of the battery pack in the group. for The SOH value of the smallest number in the group, The SOP (Start of Production) value for the i-Ni battery pack is based on temperature T. This represents the maximum safe discharge current of battery pack i, considering only the current SOC conditions. This represents the maximum safe discharge current of battery pack i, considering only the current temperature conditions.

[0073] Subsequently, the maximum permissible total discharge current of all battery packs was compared to obtain the maximum discharge capacity. The corresponding battery pack group, i.e., the target battery pack group. Among them, The calculation formula is as follows:

[0074] (7);

[0075] At this time, the target battery pack can simultaneously turn on its main MOSFET for charging and discharging, while other battery packs only turn on current-limited discharge (e.g., =10A), ensuring the system has the strongest output capability under discharge conditions, while avoiding excessive current in a single battery pack that triggers protection.

[0076] Based on the number of target battery pack groups, the system further determines the open-circuit battery packs and the master battery pack: 1) Single group case: When there is only one target battery pack group, all battery packs in the group are open-circuit battery packs, and the battery pack with the lowest open-circuit voltage in the group is selected as the master battery pack. 2) Multiple group case: When there are multiple target battery pack groups with the same or similar discharge SOP, the system selects the battery pack group with the highest average voltage as the open-circuit battery pack group to ensure that the group with higher SOC participates in the paralleling first, thereby improving the continuous output capability of the system. The battery pack with the lowest open-circuit voltage in this group is selected as the master battery pack to achieve effective voltage leveling of high and low packs by the main MOSFET. It should be noted that when selecting the master battery pack in a group, if there are multiple battery packs with the lowest open-circuit voltage, the battery pack with the largest number can be selected as the master battery pack.

[0077] In addition, after selecting the target battery pack and determining the main battery pack, the system also needs to process the remaining unopened battery packs to ensure the safe and stable operation of the entire battery system under different operating conditions and to optimize voltage balancing. The specific process is as follows:

[0078] When the system is not discharging (e.g., only in a power-on quiescent state or standby mode), battery packs without main MOSFETs can still be charged / discharged through their respective charge / discharge Buck circuits. Battery packs with voltages higher than the main battery pack open their discharge Buck circuits to discharge to the system bus, while those with voltages lower than the main battery pack open their charging Buck circuits and are charged by the bus. The system operates according to the voltage of the main battery pack and the opening threshold defined in formula (4) until the voltage difference between these battery packs and the main battery pack meets the merging condition. At this point, the charge / discharge transistors of the unopened battery packs are safely opened, achieving voltage leveling from the high-voltage pack to the low-voltage pack, thereby optimizing voltage balance without affecting system safety.

[0079] When the system is in a discharging state, the current system discharge current must be considered. With the target battery pack's maximum permissible total discharge current The relationship between them: If If the voltage is too high, the system will prioritize starting the battery pack with the higher voltage in the unopened main MOSFET, thus maximizing the overall system output capacity and reducing the risk of local overcurrent. If If the voltage difference is small, the parallel operation is similar to the static parallel operation mode: the discharge Buck of the unopened battery pack is still turned on to slowly level the voltage difference between the battery packs, while waiting for the voltage difference to meet the formula (4) before officially turning on the main MOSFET for parallel operation.

[0080] Please refer to the following: Figure 4 and Figure 5 This paper further describes the implementation process of determining the host battery pack and the open-tube battery pack when the target voltage difference does not meet the fully open tube parallel pack condition and the activation state is button activated, using a specific example. The implementation process is as follows:

[0081] To facilitate expression and calculation, let battery pack i be the allowable differential pressure. And the value of each package , All values ​​are taken to be equal under ideal conditions, meaning that the SOP (Start of Production) of all battery packs is equal. For example... Figure 4 As shown, at this time, battery pack i=8, and battery pack 1 has no pack with a smaller number than it, so Battery pack 2 has a smaller serial number than battery pack 1. The inclusion condition is met, therefore The quantity that meets the condition of a differential pressure within 1V is: , , , , , , , From formulas (6) and (7), it can be seen that if each battery pack... , If the difference is not significant big It will be larger. At this time, battery pack 4 can be taken as the main pack, and battery packs 1, 2, 3, and 4 can be turned on simultaneously as a group. Under non-ideal conditions, the actual calculation of each group of batteries needs to be obtained according to formulas (6) and (7). By comparison, the main pack and the open-tube battery pack can be identified.

[0082] like Figure 5 As shown, the number of units satisfying the condition of a differential pressure within 1V is [number missing]. , , , , , , , .at this time Right now Two target battery packs meet the conditions for opening the tubes. Since button activation defaults to the discharge state, the battery pack with the higher average voltage (i.e., higher SOC) is selected as the battery pack to open the tubes. That is, battery pack 4 is selected as the main battery pack. Battery packs 2, 3, and 4 are opened simultaneously as a group to ensure that the system output capacity is maximized and the continuous output time is longer. In non-ideal conditions, the actual calculation of each battery pack is still required according to formulas (6) and (7). By comparison, it is determined whether there are multiple battery packs that meet the conditions for opening the tubes, and the battery pack with the higher average voltage, i.e., the higher SOC, is selected for opening the tubes.

[0083] In this embodiment, by grouping battery packs whose target voltage difference does not meet the fully open diode paralleling condition and calculating the maximum allowable total discharge current of each group, the system can scientifically select the battery pack group with the strongest output capability as the target battery pack group. This ensures that the system has maximum discharge capacity and continuous output time in the button-activated discharge mode. Simultaneously, by selecting the battery pack with the smallest open-circuit voltage within the target battery pack group as the host battery pack and determining the corresponding open-diode battery pack, the system achieves safe voltage compensation and equalization control of the high-voltage pack to the low-voltage pack. This method can dynamically adjust the paralleling strategy when there is a large battery voltage difference or inconsistent battery states, avoiding overcurrent or overload of a single battery pack, ensuring that the system still has optimal current output capability in the non-fully open diode state, while improving battery life and overall operational safety. Furthermore, by combining charge / discharge Buck for auxiliary voltage leveling, the voltage equalization effect between battery packs is further improved, enabling the system to maintain stable and efficient operation under different operating conditions.

[0084] In some embodiments, the activation state of the battery pack system includes a photovoltaic / grid activation state, and the target current includes the maximum allowable total charging current. When the target voltage difference does not meet the fully open-circuit battery pack activation condition, the battery packs are grouped to obtain grouped battery pack groups. Based on the battery pack groups, the battery pack group with the largest target current is selected as the target battery pack group. This includes: when the target voltage difference does not meet the fully open-circuit battery pack activation condition and the activation state is a photovoltaic / grid activation state, grouping each battery pack according to the open-circuit voltage and open-circuit threshold of each sorted battery pack to obtain grouped battery pack groups; calculating the maximum allowable total charging current of each group of battery packs; and selecting the battery pack group with the largest maximum allowable total charging current as the target battery pack group.

[0085] In some embodiments, determining an open-circuit battery pack based on a target battery pack group and selecting the battery pack with the smallest open-circuit voltage in the target battery pack group as the master battery pack includes: when the number of target battery pack groups is one, determining that the battery packs in the target battery pack group are open-circuit battery packs and selecting the battery pack with the smallest open-circuit voltage in the target battery pack group as the master battery pack; when the number of target battery pack groups is multiple, selecting the battery packs in the target battery pack group with the smallest average voltage as open-circuit battery packs and selecting the battery pack with the smallest open-circuit voltage in the target battery pack group with the smallest average voltage as the master battery pack.

[0086] When the target voltage difference calculated after system power-on does not meet the preset full-open circuit conditions, and the system is in photovoltaic / grid activation state (default charging mode), the system will group the battery packs to ensure balanced current distribution and maximize system safety and output capacity even when full-open circuit conditions are not possible. The specific implementation process is as follows:

[0087] The system, based on the list of battery packs sorted by open-circuit voltage obtained in step S11 and the open-circuit threshold, sequentially performs group statistics on each battery pack. For the sorted battery pack i, the system counts those with a voltage higher than battery pack i and a voltage difference between them that of battery pack i and battery pack i within a certain range. Number of battery packs within the range (Excluding battery pack i itself), and these battery packs together with battery pack i form a battery pack group. In this way, each battery pack and its safe-to-combine high-voltage neighboring packs form a separate battery pack group.

[0088] For each group The system takes the charging SOP of the battery pack with the lowest voltage in the group and multiplies it by the number of battery packs in the group. +1), to obtain the maximum allowable total charging current of this group. The calculation formula is as follows:

[0089] (8);

[0090] in, This represents the SOP (Start of Production) value of the battery pack (i-Ni) based on SOC (State of Charge) limitations, where i is the value of the battery pack. The highest serial number of the battery pack in the group. The number of battery packs after excluding battery pack i is given; battery pack (i-Ni) is... The smallest number of the battery pack in the group. for The SOH value of the smallest number in the group, The SOP (Start of Production) value for the i-Ni battery pack is based on temperature T. This represents the maximum safe charging current of battery pack i, considering only the current SOC conditions. This represents the maximum safe charging current for battery pack i, considering only the current temperature conditions.

[0091] Subsequently, the maximum permissible total charging current of all battery packs was compared to obtain the maximum charging capacity. The corresponding battery pack group, i.e., the target battery pack group. Among them, The calculation formula is as follows:

[0092] (9);

[0093] At this time, the target battery pack can simultaneously activate its main MOSFET for charging and discharging, while other battery packs only activate current-limited charging (e.g., ...). =10A), at which point the system's current absorption capacity is at its strongest, preventing excessive single-pack current from triggering protection and affecting system charging, thus ensuring the system's safety while maximizing its current absorption capacity.

[0094] Based on the number of target battery pack groups, the system further determines the open-circuit battery packs and the master battery pack: 1) Single group case: When there is only one target battery pack group, all battery packs in the group are open-circuit battery packs, and the battery pack with the lowest open-circuit voltage in the group is selected as the master battery pack. 2) Multiple group case: When there are multiple target battery pack groups with the same or similar charging SOP, the system selects the battery pack group with the lowest average voltage as the open-circuit battery pack group to ensure that the group with the lower SOC participates in the paralleling first, thereby improving the continuous output capability of the system. The battery pack with the lowest open-circuit voltage in this group is selected as the master battery pack to achieve effective voltage leveling of high and low packs by the main MOSFET. It should be noted that when selecting the master battery pack in a group, if there are multiple battery packs with the lowest open-circuit voltage, the battery pack with the largest number can be selected as the master battery pack.

[0095] In photovoltaic or grid charging activation systems, the system uses the real-time measured charging current to activate the system. With the maximum allowable total charging current of the selected target battery pack Comparison. When Greater than or close to When the voltage is high, it indicates that the system has a large charging capacity and needs to prioritize the use of the open-circuit strategy to fully absorb current. Therefore, the system sequentially turns on the main MOSFETs of the battery pack from the unopened battery pack in order of increasing open-circuit voltage to achieve charging compensation for the low-voltage battery pack, thereby quickly leveling the voltage difference between the battery packs and ensuring voltage balance and charging efficiency. During this process, the voltage difference is always constrained by formula (4) to ensure that there is no risk of overvoltage or overcurrent during charging.

[0096] like Less than If the system charging demand is low, the main MOSFET is not turned on immediately. Instead, the charging Buck transistor is used to assist in charging the battery pack without the main MOSFET turned on, slowly increasing the voltage of the low-voltage battery pack so that the voltage difference between it and the main battery pack gradually reaches the parallel charging condition specified in formula (4). Then, the main MOSFET is turned on to perform the parallel charging operation. This strategy effectively balances system charging capacity and battery safety, achieving a balanced control of high-efficiency charging and voltage equalization, avoiding excessive current in a single pack that could trigger protection actions, and extending the overall lifespan of the battery pack.

[0097] Please refer to the following: Figure 6 This paper further describes the implementation process of determining the main battery pack and the battery pack with open diodes using a specific example when the target voltage difference does not meet the conditions for full-open diodes and the activation state is photovoltaic / grid activation state. The implementation process is as follows:

[0098] To facilitate expression and calculation, let battery pack i be the allowable differential pressure. And the value of each package , All values ​​are taken to be equal under ideal conditions, meaning the SOP (Start of Production) of all battery packs is equal. (This is consistent with the above.) Figure 4 Similarly, the number of units satisfying the condition of a differential pressure within 1V is... , , , , , , , From formulas (8) and (9), it can be seen that if each battery pack... , If the difference is not significant big It will be larger. At this time, battery pack 4 can be taken as the main pack, and battery packs 1, 2, 3, and 4 can be turned on simultaneously as a group. Under non-ideal conditions, the actual calculation of each group of batteries needs to be obtained according to formulas (8) and (9). By comparison, the main pack and the open-tube battery pack can be identified.

[0099] like Figure 6 As shown, the number of units satisfying the condition of a differential pressure within 1V is [number missing]. , , , , , , , .at this time Right now Two target battery packs meet the conditions for power-on. Since photovoltaic / grid charging activation defaults to the charging state, the battery pack with the lower average voltage (i.e., lower SOC) is selected as the power-on battery pack. That is, battery pack 7 is selected as the main battery pack. Battery packs 5, 6, and 7 are powered on simultaneously to ensure that the system can maintain high-power charging for a longer period while maximizing its absorption capacity. In non-ideal conditions, the actual calculation of each battery pack is still required according to formulas (8) and (9). By comparison, it is determined whether there are multiple battery packs that meet the conditions for opening the tubes, and the battery pack with the lower average voltage, i.e., the lower SOC, is selected for opening the tubes.

[0100] In this embodiment, by grouping battery packs in photovoltaic or grid-activated states where the target voltage difference does not meet the conditions for full MOSFET opening and parallel charging, and selecting the target battery pack group based on the maximum allowable total charging current of each group, the system can optimize and balance current distribution even when full MOSFET opening and parallel charging is not possible. The system selects the battery pack group with the lowest average voltage as the MOSFET-opening battery pack, and within that group, selects the battery pack with the lowest open-circuit voltage as the master battery pack. This effectively ensures the main MOSFET's leveling effect on the charging of each battery pack, thereby quickly reducing the voltage difference between battery packs and improving charging efficiency. Simultaneously, by monitoring the system charging current in real time and matching it with the maximum allowable total charging current of the target battery pack group, the system can prioritize MOSFET opening for rapid current absorption when the charging capacity is high, and use the auxiliary charging and discharging Buck module to smoothly level the voltage difference when the charging capacity is low, avoiding the risk of single-pack overcurrent or overcharge. This grouping and parallel charging strategy, along with the master battery pack selection strategy, not only ensures the system can achieve maximum current absorption capacity and continuous high-power charging even when not fully MOSFET open, but also considers battery safety and lifespan, improving the stability, charging efficiency, and reliability of the entire battery system.

[0101] In some embodiments, the method further includes: when a battery pack is hot-swapped, determining whether the hot-swapped battery pack is a host battery pack; when the hot-swapped battery pack is a host battery pack, determining the host battery pack based on a first hot-swapping strategy; when the hot-swapped battery pack is not a host battery pack, determining the open-tube battery pack based on a second hot-swapping strategy.

[0102] When the system detects a hot-swapping event of a battery pack, it first identifies the hot-swapped battery pack to determine if it is the current host battery pack. The host battery pack refers to the battery pack that assumes the main control role under the current parallel strategy and levels the voltage of other battery packs through the main MOSFET. If the hot-swapped battery pack is the host battery pack, the host battery pack switching strategy is triggered.

[0103] Specifically, when the hot-swappable battery pack is the main battery pack, the main battery pack is determined based on the first hot-swappable strategy, including: when the hot-swappable battery pack is the main battery pack, determining whether all open-circuit battery packs in the target battery pack group where the main battery pack is located have been disconnected; if all open-circuit battery packs in the target battery pack group where the main battery pack is located have been disconnected, determining the current state of the battery pack system; if the current state is a discharging state, selecting the battery pack with the largest open-circuit voltage as the main battery pack; if the current state is a charging state, selecting the battery pack with the smallest open-circuit voltage as the main battery pack; if not all open-circuit battery packs in the target battery pack group where the main battery pack is located have been disconnected, selecting the battery pack with the smallest open-circuit voltage among the open-circuit battery packs in the target battery pack group where the main battery pack is located as the main battery pack.

[0104] When the battery pack being hot-swapped is the main battery pack, the system determines the new main battery pack based on the first hot-swappable strategy. The specific process is as follows:

[0105] The system first checks whether all open-circuit battery packs in the target battery pack group containing the hot-swappable host battery pack have been disconnected. The target battery pack group refers to a set of battery packs that can be grouped together according to a grouping strategy. Open-circuit battery packs refer to battery packs that can currently participate in charging and discharging to level out their voltage via the main MOSFET. For example... Figure 7 As shown in (a), (a) is a schematic diagram before the hot-plug event is triggered in the discharge state. At this time, the target battery pack group (battery packs 5, 6, and 7, and the host battery pack is battery pack 7).

[0106] If the target battery pack group where the original host battery pack is located still has some open-tube battery packs online, such as Figure 7 As shown in (b), the system selects the battery pack with the smallest open-circuit voltage from the group of open-tube battery packs as the new host battery pack. The battery pack with the smallest open-circuit voltage refers to the battery pack with the largest sequence number in the sorted battery packs.

[0107] If all open-tube battery packs in the target battery pack group where the host battery pack is located have gone offline, such as Figure 7As shown in (c), when the system is in discharge mode (i.e., the default power-on or button activation is in discharge mode), the system selects the battery pack with the highest open-circuit voltage as the new main battery pack to ensure maximum system output capacity during discharge. If the system is in charging mode (i.e., photovoltaic / grid activation mode or system default charging), the system selects the battery pack with the lowest open-circuit voltage as the new main battery pack. Figure 7 (Not shown) so that the low-voltage battery pack voltage can be leveled out first during charging to improve the system's current absorption capacity.

[0108] After the system completes the switching of the host battery pack, it needs to calculate the maximum allowable total charging current of the current system according to formulas (10) and (11). and maximum permissible total discharge current And it is combined with the system based on the real-time measured charging current. and discharge current A comparison is made to determine whether a protection action or alarm is triggered, ensuring the safety of hot-swapping operations. Battery packs without open MOSFETs receive auxiliary charging and discharging through a DC-DC current limiting module to maintain stable system current. The calculation processes for formulas (10) and (11) are as follows:

[0109] (10);

[0110] (11);

[0111] Where m1~mn are the numbers of the MOSFETs, n represents the total number of battery packs with MOSFETs, and i is the maximum number of battery packs in the system. , The charging and discharging current of the current limiting module, For battery pack numbered m1, considering only the current SOC condition, what is the maximum safe charging current of the battery pack? This is the maximum safe charging current for battery pack numbered m1, considering only the current temperature conditions. The same applies to other battery packs, and will not be repeated here.

[0112] In this embodiment, through a first hot-swap strategy, when the main battery pack is hot-swapped, the system can automatically and quickly select a new main battery pack. It intelligently judges the current system state (charging or discharging) and the online status and voltage characteristics of the target battery pack, thereby ensuring stable operation of the parallel battery system under hot-swap operations. This strategy effectively avoids the risk of voltage imbalance or current surges caused by the main battery pack being disconnected. Simultaneously, by selecting the battery pack with the highest or lowest open-circuit voltage as the main battery, it ensures that the system has maximum output capacity in the discharging state and maximum absorption capacity in the charging state. Furthermore, by updating the system's maximum permissible total charge and discharge current in real time and combining it with current-limiting protection measures, the system's safety and reliability are further improved.

[0113] Specifically, when the hot-swapped battery pack is not the main battery pack, based on the second hot-swapping strategy, the open-circuit battery pack is determined, including: when the hot-swapped battery pack is not the main battery pack, updating the maximum allowable total charging current and the maximum allowable total discharging current of the parallel battery pack system, and determining the current state of the parallel battery pack system; when the current state is charging, obtaining the current charging current of the parallel battery pack system; when the maximum allowable total charging current is less than the current charging current, performing open-circuit and parallel processing from the non-open-circuit battery pack with the smallest open-circuit voltage until the maximum allowable total charging current is not less than the current charging current; when the current state is discharging, obtaining the current discharging current of the parallel battery pack system; when the maximum allowable total discharging current is less than the current discharging current, performing open-circuit and parallel processing from the non-open-circuit battery pack with the largest open-circuit voltage until the maximum allowable total discharging current is not less than the current discharging current.

[0114] When the hot-swapped battery pack is not the main battery pack, the system dynamically adjusts the open-tube battery pack according to the second hot-swappable strategy to ensure that the system can maintain stable charging and discharging capabilities and safe operation even when the battery pack is disconnected. The specific implementation process is as follows:

[0115] The system first updates and includes the system's maximum allowable total charging current based on the current battery pack status and information about the disconnected battery pack. and maximum permissible total discharge current This step ensures that the system can accurately assess the safe charge and discharge capabilities of the remaining battery pack after hot-plugging.

[0116] Subsequently, the system detects and includes the system's operating status, including charging or discharging states. This status determination is a prerequisite for the decision to turn on the transistor, because the current distribution differs under charging and discharging conditions.

[0117] When the current state is charging, the system obtains the current charging current. If the updated maximum allowable total charging current Less than This indicates that the system's current charging capacity is insufficient to absorb the actual input current. To avoid wasting photovoltaic or grid power, the system sequentially turns on the main MOSFETs of the battery pack with the lowest voltage (those without MOSFETs) for parallel charging until the maximum allowable total charging current is not less than [a certain value]. .like Not less than If no additional pipes are needed, the system will maintain the existing pipe-opening state and report the status of the unopened battery pack to the outside via the host.

[0118] When the current state is discharge state, the system obtains the current discharge current. If the updated maximum allowable total discharge current Less than This indicates that a partial battery pack disconnection may prevent the system from meeting the load discharge requirements. In this case, the system sequentially turns on the main MOSFETs of the battery packs with the highest voltage (those without MOSFETs) to perform parallel discharge, until the maximum allowable total discharge current is reached. Not less than .like Not less than If the remaining battery pack is sufficient to support the current load, the system does not need to open an additional pipe; if there is no battery pack that can be opened, the system discharge must be stopped and protection measures must be triggered to prevent overcurrent or overvoltage damage to the battery pack.

[0119] In this embodiment, when the hot-swapped battery pack is not the main battery pack, the system can dynamically adjust the open-circuit battery packs based on the second hot-swappable strategy to achieve rapid compensation and balanced distribution of charging and discharging capabilities. During charging, the system can prioritize activating the low-voltage, unactivated battery packs to fully absorb photovoltaic or grid input current, avoiding power waste. During discharging, the system can prioritize activating the high-voltage, unactivated battery packs to meet load discharge requirements, preventing insufficient current from triggering system protection. This strategy ensures continuous and stable system operation even when the battery pack is disconnected, while balancing charging and discharging efficiency with battery safety, thus improving the overall battery pack lifespan and system reliability.

[0120] This application provides a method for parallel control of multiple battery packs. Through dynamic parallel control of the battery packs and intelligent selection of the host / open-circuit battery pack, it achieves safe, efficient, and balanced charge and discharge management under various activation states (such as button activation, photovoltaic / grid activation) and different operating conditions (such as fully open-circuit, partially open-circuit, and hot-swappable). Specifically, the system can dynamically determine the target battery pack group based on real-time measured open-circuit voltage, SOC, temperature, and state of health (SOH), and rationally allocate the charge and discharge current to achieve voltage leveling between the low-voltage and high-voltage battery packs. In hot-swappable battery pack scenarios, the system can intelligently switch between the host battery pack and the open-circuit battery pack to ensure continuous output of charge and discharge capacity and prevent protection actions triggered by excessive or insufficient current. Simultaneously, through charge and discharge Buck current limiting compensation, it balances battery safety and system performance, maximizing the system's charge and discharge capacity and current absorption / output capability. This method comprehensively improves the battery pack's lifespan, system stability, and ease of operation, achieving highly reliable and efficient intelligent battery management, and is suitable for electric vehicles, energy storage systems, and multi-battery pack power supply scenarios.

[0121] This application also provides an electronic device 100, which can be an electric vehicle powered by multiple battery packs, an energy storage system, a drone, or other portable or industrial electronic device requiring efficient charge and discharge management. Please refer to... Figure 8 This diagram illustrates the hardware structure of an electronic device 100 capable of performing the methods described in the above embodiments. The electronic device 100 includes: at least one processor 110; and a memory 120 communicatively connected to the at least one processor 110. Figure 8 Taking a processor 110 as an example, the memory 120 stores instructions executable by the at least one processor 110. These instructions, when executed by the at least one processor 110, enable the at least one processor 110 to perform the multi-battery pack parallel control method described in the above embodiment. The processor 110 and the memory 120 can be connected via a bus or other means. Figure 8 Taking the example of a connection between China and Israel via a bus.

[0122] The memory 120, as a non-volatile computer-readable storage medium, can be used to store non-volatile software programs, non-volatile computer-executable programs, and modules, such as the program instructions / modules corresponding to the multi-battery pack parallel control method in the embodiments of this application. The processor 110 executes various functional applications and data processing of the server by running the non-volatile software programs, instructions, and modules stored in the memory 120, thereby implementing the multi-battery pack parallel control method described in the above embodiments.

[0123] The memory 120 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created based on the use of the computing device. Furthermore, the memory 120 may include high-speed random access memory and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device. In some embodiments, the memory 120 may optionally include memory remotely located relative to the processor 110, and these remote memories may be connected to the computing device via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0124] The one or more modules are stored in the memory 120, and when executed by the one or more processors 110, the multi-battery pack parallel control method described in the above embodiment is executed.

[0125] The above-described product can execute the method provided in the embodiments of this application, and has the corresponding functional modules and beneficial effects for executing the method. Technical details not described in detail in this embodiment can be found in the multi-battery pack parallel control method described in the embodiments of this application.

[0126] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0127] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them; under the concept of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of this application as described above, which are not provided in detail for the sake of brevity; although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A multi-battery-pack parallel control method applied to a parallel-pack system, the parallel-pack system comprising a plurality of battery packs, positive and negative terminals of the plurality of battery packs being connected to positive and negative buses, respectively, through wires, the positive and negative buses being connected to an inverter, wherein, The lengths of the wires from each battery pack to the positive and negative bus bars are equal, and the method comprises: Obtaining the open circuit voltages of each battery pack, and obtaining a target voltage difference according to the open circuit voltages; When the target voltage difference meets a preset full open tube and pack condition, selecting the battery pack with the largest open circuit voltage as a host battery pack, and determining an open tube battery pack according to the host battery pack; When the target voltage difference does not meet the full open tube and pack condition, performing grouping processing on each battery pack to obtain a grouped battery pack group, and selecting a battery pack group with a target current as a target battery pack group according to the battery pack group; According to the target battery pack group, determining the open tube battery pack, and selecting the battery pack with the smallest open circuit voltage in the target battery pack group as the host battery pack.

2. The multi-cell-pack parallel control method according to claim 1, characterized by, The obtaining of the open circuit voltages of each battery pack and the obtaining of a target voltage difference according to the open circuit voltages comprises: Obtaining the open circuit voltages of each battery pack; Sorting the open circuit voltages to obtain sorted battery packs, and determining the maximum value in the open circuit voltages as a first open circuit voltage and the minimum value in the open circuit voltages as a second open circuit voltage; According to the first open circuit voltage and the second open circuit voltage, the target voltage difference is obtained.

3. The multi-cell-pack parallel control method according to claim 2, characterized by, When the target voltage difference meets a preset full open tube and pack condition, selecting the battery pack with the largest open circuit voltage as a host battery pack, and determining an open tube battery pack according to the host battery pack, comprising: Judging the target voltage difference; If the target voltage difference is not greater than an open tube threshold, selecting the battery pack corresponding to the first open circuit voltage as the host battery pack, and determining the host battery pack to the battery pack corresponding to the second open circuit voltage as the open tube battery pack according to the host battery pack; The open tube threshold is calculated by the maximum allowable charging current of the battery pack corresponding to the second open circuit voltage and the internal resistance value of the battery pack corresponding to the second open circuit voltage.

4. The multi-cell-pack parallel control method according to claim 3, characterized by, The activation state of the pack system includes a key activation state, and the target current includes a maximum allowable total discharge current, When the target voltage difference does not meet the full open tube and pack condition, performing grouping processing on each battery pack to obtain a grouped battery pack group, and selecting a battery pack group with a target current as a target battery pack group according to the battery pack group, comprising: When the target voltage difference does not meet the full open tube and pack condition, and the activation state is the key activation state, performing the grouping processing on each battery pack according to the open circuit voltages corresponding to the sorted battery packs and the open tube threshold to obtain the grouped battery pack group; Calculating the grouped battery pack group to obtain the maximum allowable total discharge current of each battery pack group; Selecting the battery pack group with the maximum allowable total discharge current as the target battery pack group.

5. The multi-cell-pack parallel control method according to claim 4, wherein The open tube battery pack is determined according to the target battery pack group, and the battery pack with the minimum open circuit voltage in the target battery pack group is selected as the host battery pack, comprising: When the number of the target battery pack group is one group, the battery pack of the target battery pack group is determined as the open tube battery pack, and the battery pack with the minimum open circuit voltage in the target battery pack group is selected as the host battery pack; When the number of the target battery pack group is multiple groups, the battery pack of the target battery pack group with the maximum average voltage is selected as the open tube battery pack, and the battery pack with the minimum open circuit voltage in the target battery pack group with the maximum average voltage is selected as the host battery pack.

6. The multi-cell-pack parallel control method according to claim 3, characterized by, The activation state of the parallel pack system includes a photovoltaic / grid activation state, and the target current includes a maximum allowed total charging current, When the target voltage difference does not satisfy the full open tube parallel pack condition, each battery pack is grouped to obtain a grouped battery pack group, and the target battery pack group with the maximum target current is selected according to the battery pack group, comprising: When the target voltage difference does not satisfy the full open tube parallel pack condition, and the activation state is the photovoltaic / grid activation state, each battery pack is respectively grouped according to the open circuit voltage and the open tube threshold of each battery pack in the sorted battery pack to obtain the grouped battery pack group; The maximum allowed total charging current of each battery pack group is calculated; The target battery pack group with the maximum maximum allowed total charging current is selected.

7. The multi-cell-pack parallel control method according to claim 6, wherein The open tube battery pack is determined according to the target battery pack group, and the battery pack with the minimum open circuit voltage in the target battery pack group is selected as the host battery pack, comprising: When the number of the target battery pack group is one group, the battery pack of the target battery pack group is determined as the open tube battery pack, and the battery pack with the minimum open circuit voltage in the target battery pack group is selected as the host battery pack; When the number of the target battery pack group is multiple groups, the battery pack of the target battery pack group with the minimum average voltage is selected as the open tube battery pack, and the battery pack with the minimum open circuit voltage in the target battery pack group with the minimum average voltage is selected as the host battery pack.

8. The multi-cell pack parallel control method according to claim 1, characterized by, The method further comprises: When the battery pack is hot-plugged, it is determined whether the hot-plugged battery pack is the host battery pack; When the hot-plugged battery pack is the host battery pack, the host battery pack is determined based on a first hot-plugging strategy; When the hot-plugged battery pack is not the host battery pack, the open tube battery pack is determined based on a second hot-plugging strategy.

9. The multi-cell pack parallel control method according to claim 8, wherein When the hot-plugged battery pack is the host battery pack, the host battery pack is determined based on a first hot-plugging strategy, comprising: When the hot-plugged battery pack is the host battery pack, it is determined whether the open tube battery pack of the target battery pack group where the host battery pack is located has been dropped. If all the open tube battery packs in the target battery pack group where the host battery pack is located have been disconnected, determine the current state of the parallel battery system; If the current state is discharging, select the battery pack with the largest open circuit voltage as the host battery pack; If the current state is charging, select the battery pack with the smallest open circuit voltage as the host battery pack; If all the open tube battery packs in the target battery pack group where the host battery pack is located have not been disconnected, select the battery pack with the smallest open circuit voltage among the open tube battery packs in the target battery pack group where the host battery pack is located as the host battery pack.

10. The multi-cell pack parallel control method according to claim 8, characterized by, When the hot-plugged battery pack is not the host battery pack, based on a second hot-plugging strategy, the open tube battery pack is determined, including: When the hot-plugged battery pack is not the host battery pack, update the maximum allowed total charging current and the maximum allowed total discharging current of the parallel battery system, and determine the current state of the parallel battery system; When the current state is charging, obtain the current charging current of the parallel battery system; When the maximum allowed total charging current is less than the current charging current, perform open tube and parallel battery processing from the unopened tube battery pack with the smallest open circuit voltage until the maximum allowed total charging current is not less than the current charging current; When the current state is discharging, obtain the current discharging current of the parallel battery system; When the maximum allowed total discharging current is less than the current discharging current, perform open tube and parallel battery processing from the unopened tube battery pack with the largest open circuit voltage until the maximum allowed total discharging current is not less than the current discharging current.

11. An electronic device, comprising: comprise: at least one processor; and a memory connected in communication with the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method of any one of claims 1-10.

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