Battery equalization control method and system

Abstract

The invention relates to the technical field of batteries, provides a battery equalization control method and system, and aims to solve the technical problems that in the prior art, an equalization circuit is frequently triggered to be started, an over-temperature alarm of an equalization circuit board is easily caused, the equalization effect is poor, and the aging of the equalization circuit board is further worsened due to frequent starting of the equalization circuit. Comprising the following steps: monitoring the voltage, current and temperature of each single battery in a battery pack in real time by using a BMS (Battery Management System), and obtaining the SOC of each single battery and the PackSOC of the battery pack; whether the battery pack reaches the equalization circuit opening condition or not is judged in real time through a BMS, if yes, an equalization circuit is opened, the equalization electric quantity needed by each single battery in the battery pack is calculated, the equalization time is calculated according to the equalization electric quantity, and equalization adjustment is carried out; and judging whether the battery pack reaches the equalization circuit closing condition or not in real time by using a BMS, and if so, closing the equalization circuit.

Description

Technical Field

[0001] The present invention belongs to the technical field of batteries, and in particular relates to a battery balancing control method and system. Background Art

[0002] The power battery of an electric vehicle is composed of several single cells connected in series. When the voltage difference among these series-connected single cells is large, that is, the consistency is poor, the power and energy released by the battery pack will be affected. At this time, the balancing function needs to be turned on to maintain the consistency of the single cells in order to maximize the energy efficiency of the battery.

[0003] In the existing battery management system (BMS) technology, the start and shut down conditions of the battery balancing circuit are mainly based on the voltage difference between the single cells in the battery pack. When the voltage difference between the single cells in the battery pack exceeds the preset threshold, the balancing circuit will start, and once the voltage difference between the single cells decreases to below the preset shutdown threshold, the balancing circuit will stop working.

[0004] The prior art has the following technical problems:

[0005] 1. The existing battery balancing method will frequently trigger the balancing circuit to turn on, which may easily cause the balancing circuit board to overheat and cause poor balancing effect.

[0006] 2. Frequent activation of the equalization circuit will further deteriorate the aging of the equalization circuit board. Summary of the invention

[0007] The present invention provides a battery balancing control method and system, aiming to solve the technical problems existing in the above-mentioned prior art that the balancing circuit will be frequently triggered to start, which may easily cause an over-temperature alarm of the balancing circuit board, resulting in poor balancing effect, and the frequent start of the balancing circuit will further aggravate the aging of the balancing circuit board.

[0008] The technical solution of the present invention to solve the above technical problem is as follows: a battery balancing control method, comprising:

[0009] Acquire the attribute data of the battery pack in real time, wherein the attribute data includes temperature, voltage and SOC;

[0010] Based on the attribute data, using the BMS to determine in real time whether the battery pack meets the balancing circuit start condition, if not, not starting the balancing circuit, if yes, starting the balancing circuit to balance the battery pack;

[0011] After the balancing circuit is turned on, the BMS is used to determine in real time whether the battery pack has reached the balancing circuit closing condition. If so, the balancing circuit is closed. If not, the process returns to continue determining whether the battery pack has reached the balancing circuit closing condition.

[0012] Furthermore, based on the voltage and SOC of the single cell in the battery pack, a V-SOC characteristic curve of the single cell is generated, and the stable stage of the single cell is divided into a plateau period and a non-plateau period according to the V-SOC characteristic curve, and the SOC in the range of [20%, 80%) is defined as the plateau period, and the SOC in the range of [0, 20%) or [80%, 100%) is defined as the non-plateau period.

[0013] Furthermore, the equalization circuit start-up condition includes the following sub-conditions:

[0014] A difference ΔSOC between a maximum SOC and a minimum SOC of a single battery in the battery pack is between a first SOC threshold and a second SOC threshold;

[0015] The difference ΔV between the highest voltage and the lowest voltage of the single battery in the battery pack is greater than the voltage threshold, and both the single battery with the highest voltage and the single battery with the lowest voltage are in a non-plateau period;

[0016] The highest battery temperature of the single battery in the battery pack is greater than T0℃;

[0017] The PackSOC of the battery pack is greater than the PackSOC threshold;

[0018] Each of the above sub-conditions is independently judged in real time, and when all sub-conditions are met, the equalization circuit start function is triggered.

[0019] Furthermore, the balancing circuit closing condition includes the following sub-conditions:

[0020] The difference ΔSOC between the highest SOC and the lowest SOC of the single battery in the battery pack is less than or equal to the first SOC threshold or the difference ΔSOC is greater than or equal to the second SOC threshold

[0021] The difference ΔV between the highest voltage and the lowest voltage of the single battery in the battery pack is less than or equal to the voltage threshold, and the single battery with the highest voltage and the single battery with the lowest voltage are both in the plateau phase;

[0022] The maximum battery temperature of the single battery in the battery pack is less than or equal to T0℃;

[0023] The PackSOC of the battery pack is less than or equal to the PackSOC threshold;

[0024] Each of the above sub-conditions is independently judged in real time, and when any of the sub-conditions is met, the balancing circuit shutdown function is triggered.

[0025] Further, the battery pack is balanced and adjusted to calculate the balanced power required by each single battery in the battery pack, and then the balanced time is calculated according to the balanced power, which specifically includes:

[0026] The SOC of the single cells in the battery pack is obtained, and the single cell with the highest SOC is used as the reference single cell. The SOC of other single cells in the battery pack is compared with the SOC of the reference single cell to obtain the balanced power required by each single cell. The formula for calculating the balanced power is:

[0027] ΔQ=C×(SOC ref -SOC i )

[0028] Among them, C represents the rated capacity of the single battery, SOC ref Indicates the SOC of the reference single battery, SOC i Represents the SOC of the i-th single cell;

[0029] The formula for calculating the balancing time according to the balancing power is:

[0030]

[0031] Among them, I bal Indicates the maximum balancing current of the balancing circuit.

[0032] Furthermore, it also includes:

[0033] The BMS starts or shuts down the balancing circuit through an electronic switch located between the single battery and the balancing circuit; when the electronic switch is turned on, the balancing circuit starts to work, and when the electronic switch is turned off, the balancing circuit stops working.

[0034] Furthermore, it also includes:

[0035] When the balancing circuit is turned on, the BMS is used to obtain the circuit board temperature of the PCB board carrying the balancing circuit. When the circuit board temperature is less than T1°C, the balancing channel of the balancing circuit is in a fully open state; when the circuit board temperature is greater than or equal to T1°C and less than T2°C, the balancing channel of the balancing circuit is closed by half; when the circuit board temperature is greater than or equal to T2°C and less than T3°C, the balancing channel of the balancing circuit is closed by two-thirds, and when the circuit board temperature is greater than or equal to T3°C, the balancing circuit is turned off.

[0036] In a second aspect, in order to solve the above technical problems, the present invention further provides a battery balancing control system, which is implemented based on a battery pack, a balancing circuit and a BMS, and specifically includes:

[0037] A battery pack, which has multiple single cells connected in series;

[0038] The BMS, connected with the battery pack, comprises:

[0039] A data acquisition unit, used for acquiring attribute data in the battery pack in real time, the attribute data including temperature, voltage and SOC; a condition determination unit, used for determining in real time whether the battery pack meets the equalization circuit start-up condition based on the attribute data, if not, not turning on the equalization circuit, if yes, turning on the equalization circuit to perform equalization adjustment on the battery pack; and also used for determining in real time whether the battery pack meets the equalization circuit shutdown condition after the equalization circuit is turned on, if yes, turning off the equalization circuit, if no, returning to continue determining whether the battery pack meets the equalization circuit shutdown condition;

[0040] The balancing circuit is connected between the battery pack and the BMS and is used to balance the SOC of each single battery in the battery pack.

[0041] In a third aspect, in order to solve the above technical problems, the present invention further provides an electronic device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the battery balancing control method of the present application when executing the computer program.

[0042] In a fourth aspect, in order to solve the above technical problem, the present invention further provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the battery balancing control method of the present application is implemented.

[0043] Compared with the prior art, the present invention has the following advantages:

[0044] 1. The present invention couples multiple judgment conditions such as battery temperature, equalization circuit board temperature, SOC, non-voltage platform, etc. to reasonably set the equalization circuit opening condition and the equalization circuit closing condition. Since the opening condition and closing condition combine multiple factors, the opening and closing of the equalization circuit are more reasonable and the equalization circuit will not be triggered frequently.

[0045] 2. By controlling the balancing channel of the balancing circuit according to the temperature of the balancing circuit board and shutting down the balancing circuit when the temperature of the balancing circuit board is too high, the number of over-temperature alarms of the balancing circuit board is effectively reduced, and the balancing effect is improved while protecting the balancing circuit and extending the service life of the circuit board.

[0046] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0048] Figure 1 A schematic flow chart of a battery balancing control method according to an embodiment of the present invention is shown;

[0049] Figure 2 A schematic structural diagram of an electronic device according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] In lithium-ion battery packs and other types of multi-battery series configurations, the charge and discharge states of individual cells may be inconsistent due to manufacturing differences, uneven aging, temperature effects, etc. If this inconsistency is not managed, it will significantly shorten the overall life of the battery pack and reduce its performance. Therefore, this application uses a balancing circuit in a battery management system (BMS) to ensure that the SOC (State of Charge) between individual cells in the battery pack is as consistent as possible.

[0052] Figure 1 A schematic diagram of a flow chart of a battery balancing control method according to an embodiment of the present invention is shown. Figure 1 As shown, a battery balancing control method according to an embodiment of the present invention includes:

[0053] Acquire the attribute data of the battery pack in real time, wherein the attribute data includes temperature, voltage and SOC;

[0054] Based on the attribute data, using the BMS to determine in real time whether the battery pack meets the balancing circuit start condition, if not, not starting the balancing circuit, if yes, starting the balancing circuit to balance the battery pack;

[0055] After the balancing circuit is turned on, the BMS is used to determine in real time whether the battery pack has reached the balancing circuit closing condition. If so, the balancing circuit is closed. If not, the process returns to continue determining whether the battery pack has reached the balancing circuit closing condition.

[0056] In the present invention, the BMS continuously monitors the voltage of each single cell. When the single cell reaches the start-up condition of the balancing circuit, the BMS starts the balancing circuit through an electronic switch (usually a MOSFET or a similar power switch device). The electronic switch is located between the single cell and the balancing circuit. When the electronic switch is turned on, the balancing circuit starts to work.

[0057] In this embodiment, the BMS is used to monitor the voltage, current and temperature of each single cell in the battery pack in real time, and the SOC of each single cell and the PackSOC of the battery pack are obtained based on the voltage, current and temperature of the single cell; and the equalization circuit opening condition and the equalization circuit closing condition are generated based on the SOC, voltage, temperature, stable stage of the single cell in the battery pack, and the PackSOC of the battery pack;

[0058] There are two main working modes of equalization circuits: active equalization and passive equalization.

[0059] Active balancing: Energy is transferred from high-voltage cells to low-voltage cells through electronic switches, which usually involves a DC-DC converter or transformer to efficiently transfer energy between cells.

[0060] Passive balancing: The excess energy of high-voltage single cells is dissipated through resistors through electronic switches. This method is simple but inefficient because the energy is lost in the form of heat.

[0061] In electric vehicles (EV) and energy storage systems (ESS), due to the large battery capacity and high requirements for efficiency and life, more complex active balancing circuits can be used. In portable electronic devices, due to the small battery capacity, passive balancing solutions can be used.

[0062] Optionally, the SOC range of [20%, 80%) is defined as the plateau period, and the SOC range of [0, 20%) or [80%, 100%) is defined as the non-plateau period.

[0063] The plateau period refers to the stage in which the voltage of a single cell remains relatively stable within the SOC (state of charge) range of 20%-80%. During this period, even if the battery continues to charge or discharge, its voltage change is very small, forming a "plateau". The existence of the plateau period enables the single cell to provide a stable output voltage within the SOC range.

[0064] The non-plateau phase refers to the stage where the voltage of a single cell changes significantly with SOC, which usually occurs when the battery is close to being fully discharged (0%-20% SOC range) or close to being fully charged (80%-100% SOC range). During the non-plateau phase, the battery voltage will rise or fall rapidly, which reflects the drastic changes in the chemical reactions inside the single cell.

[0065] Since overcharging or over-discharging may cause battery damage or safety issues such as thermal runaway during the non-plateau period, whether the single cell is in the non-plateau period is used as one of the conditions for starting the balancing circuit.

[0066] Optionally, the equalization circuit start-up condition includes the following sub-conditions:

[0067] A difference ΔSOC between a maximum SOC and a minimum SOC of a single battery in the battery pack is between a first SOC threshold and a second SOC threshold;

[0068] The difference ΔV between the highest voltage and the lowest voltage of the single battery in the battery pack is greater than the voltage threshold, and both the single battery with the highest voltage and the single battery with the lowest voltage are in a non-plateau period;

[0069] The highest battery temperature of the single battery in the battery pack is greater than T0℃; (At low temperatures, the internal resistance of the battery will increase, and equalization may cause additional stress on the battery. In order to avoid potential battery damage, it is a preventive measure to enable the equalization function when the battery temperature is greater than T0℃.)

[0070] The PackSOC of the battery pack is greater than the PackSOC threshold; (In this case, the charge level of the battery pack has reached a higher state, which is used as one of the conditions for turning on the balancing circuit to ensure the safety of the battery pack and extend its life.)

[0071] Each of the above sub-conditions is independently judged in real time, and when all sub-conditions are met, the equalization circuit start function is triggered.

[0072] In this embodiment, the sub-condition also includes: the battery pack is in the process of discharging or charging. This sub-condition is implemented by monitoring the mode of the BMS. If the BMS is in AC mode, DC mode, and Drive mode, it means that the battery pack is in the process of discharging or charging. Among them, AC mode refers to the mode in which the battery pack is connected to an AC power source for charging or discharging; DC mode refers to the situation in which the battery pack is directly connected to a DC power source or a load. In electric vehicles (EVs) or hybrid electric vehicles (HEVs), the DC mode is mainly used to power the drive motor or on-board electronic equipment; Drive mode refers to the battery pack directly supplying power to the vehicle's power system.

[0073] Once the required balancing time and power are calculated, the BMS will control the electronic switches (such as MOSFETs) in the balancing circuit to guide the current from the single cell with high SOC to the single cell with low SOC (active balancing), or dissipate the excess energy of the single cell with high SOC through a resistor (passive balancing) until the SOC in the battery pack reaches the predetermined balancing state.

[0074] During the balancing process, the BMS continuously monitors the battery status to ensure that the balancing process does not cause overheating or overcharging and discharging of the battery. In addition, the balancing process is performed when the ΔSOC is between the first SOC threshold and the second SOC threshold to avoid invalid or harmful balancing.

[0075] Optionally, the balancing circuit closing condition includes the following sub-conditions:

[0076] The difference ΔSOC between the highest SOC and the lowest SOC of the single battery in the battery pack is less than or equal to the first SOC threshold or the difference ΔSOC is greater than or equal to the second SOC threshold

[0077] The difference ΔV between the highest voltage and the lowest voltage of the single battery in the battery pack is less than or equal to the voltage threshold, and the single battery with the highest voltage and the single battery with the lowest voltage are both in the plateau phase;

[0078] The maximum battery temperature of the single battery in the battery pack is less than or equal to T0℃;

[0079] The PackSOC of the battery pack is less than or equal to the PackSOC threshold;

[0080] Each of the above sub-conditions is independently judged in real time, and when any of the sub-conditions is met, the balancing circuit shutdown function is triggered.

[0081] In this embodiment, the sub-conditions also include: the battery pack is not in the discharge or charging process, that is, the BMS is not in the above-mentioned AC mode, DC mode and Drive mode;

[0082] Sub-conditions also include: the circuit board temperature is greater than or equal to T3℃. Among them, T3℃ is already an extremely high operating temperature for the battery system. Continuing to balance may cause serious safety problems, such as thermal runaway, battery damage, etc. Therefore, the BMS will automatically close all balancing channels, giving priority to the safety of the battery and system to prevent the temperature from rising further. At this time, other cooling measures may be required to reduce the temperature and check whether the system is abnormal or overheated due to external environmental factors. This strategy reflects that the BMS balances the relationship between battery performance optimization and safety protection by dynamically adjusting the balancing strategy to ensure that the battery can operate safely and efficiently under various operating conditions.

[0083] Optionally, calculating the equalization power required by each single battery in the battery pack, and then calculating the equalization time according to the equalization power specifically includes:

[0084] The SOC of the single cells in the battery pack is obtained, and the single cell with the highest SOC is used as the reference single cell. The SOC of other single cells in the battery pack is compared with the SOC of the reference single cell to obtain the balanced power required by each single cell. The formula for calculating the balanced power is:

[0085] ΔQ=C×(SOC ref -SOC i )

[0086] Among them, C represents the rated capacity of the single battery, SOC ref Indicates the SOC of the reference single battery, SOC i Represents the SOC of the i-th single cell;

[0087] The formula for calculating the balancing time according to the balancing power is:

[0088]

[0089] Among them, I bal Indicates the maximum balancing current of the balancing circuit.

[0090] Optionally, also include:

[0091] The BMS starts or shuts down the balancing circuit through an electronic switch located between the single battery and the balancing circuit; when the electronic switch is turned on, the balancing circuit starts to work, and when the electronic switch is turned off, the balancing circuit stops working.

[0092] Optionally, also include:

[0093] When the balancing circuit is turned on, the BMS is used to obtain the circuit board temperature of the PCB board carrying the balancing circuit. When the circuit board temperature is less than T1°C, the balancing channel of the balancing circuit is in a fully open state; when the circuit board temperature is greater than or equal to T1°C and less than T2°C, the balancing channel of the balancing circuit is closed by half; when the circuit board temperature is greater than or equal to T2°C and less than T3°C, the balancing channel of the balancing circuit is closed by two-thirds, and when the circuit board temperature is greater than or equal to T3°C, the balancing circuit is turned off.

[0094] In this embodiment, T0℃<T1℃<T2℃<T3℃, when the circuit board temperature is less than T1℃ and greater than or equal to T0℃, the balancing channel is fully open: under this temperature condition, the thermal load of the battery pack is low, indicating that the balancing circuit is in good working condition and there is no risk of overheating. Therefore, all balancing channels are allowed to be fully open to balance the voltage between battery cells at the fastest speed to ensure the consistency of each single battery in the battery pack. When the circuit board temperature is in the range of [T1℃, T2℃), the balancing channel is opened 1 / 2: when the temperature rises above T1℃ but does not reach T2℃, it indicates that significant heat begins to be generated during the balancing process. In order to prevent overheating, the system automatically halves the number of balancing channels opened to balance efficiency and safety, and avoid safety risks or shortened battery life due to overheating. When the circuit board temperature is in the range of [T2℃, T3℃), the balancing channel is opened 1 / 3: if the temperature rises further to above T2℃, the system enters a more sensitive temperature range at this time, and the risk of overheating is aggravated. In order to further control the thermal effect, only one-third of the balancing channels are opened, which greatly reduces the heat energy generated by balancing, ensures the safe operation of the system, and maintains the voltage balance between the single cells as much as possible. When the circuit board temperature is greater than or equal to T3℃, T3℃ is already an extremely high operating temperature for the battery system. Continuing to balance may cause serious safety problems, such as thermal runaway and battery damage. Therefore, the BMS will automatically close all balancing channels, giving priority to the safety of the battery and system to prevent the temperature from rising further. At this time, other cooling measures may be required to reduce the temperature and check whether the system has abnormalities or overheating caused by external environmental factors. This strategy reflects that the BMS balances the relationship between battery performance optimization and safety protection by dynamically adjusting the balancing strategy to ensure that the battery can operate safely and efficiently under various operating conditions.

[0095] Based on Figure 1 Based on the same principle as the method shown in , an embodiment of the present invention further provides a battery balancing control system, which is implemented based on a battery pack, a balancing circuit and a BMS, and specifically includes:

[0096] A battery pack, which has multiple single cells connected in series;

[0097] The BMS, connected with the battery pack, comprises:

[0098] A data acquisition unit, used to monitor the voltage, current and temperature of each single cell in the battery pack in real time, and to calculate based on the voltage, current and temperature of the single cell to obtain the SOC of each single cell and the PackSOC of the battery pack;

[0099] A stage division unit, for generating a V-SOC characteristic curve of the single cell based on the voltage and SOC of the single cell, and dividing the stable stage of the single cell into a plateau period and a non-plateau period according to the V-SOC characteristic curve;

[0100] A condition generating unit, for generating a balancing circuit on condition and a balancing circuit off condition based on the SOC, voltage, temperature, stable stage of the single battery in the battery pack, and the PackSOC of the battery pack;

[0101] a condition determination unit, used for determining in real time whether the battery pack meets the equalization circuit start-up condition, if not, not starting the equalization circuit, if yes, starting the equalization circuit, and calculating the equalization power required by each single battery in the battery pack, and then calculating the equalization time according to the equalization power, and performing equalization adjustment based on the equalization power and the equalization time; and also used for determining in real time whether the battery pack meets the equalization circuit shutdown condition, if yes, shutting down the equalization circuit, if not, returning to continue determining whether the battery pack meets the equalization circuit shutdown condition;

[0102] The balancing circuit is connected between the battery pack and the BMS and is used to balance the SOC of each single battery in the battery pack.

[0103] The battery balancing control system of the embodiment of the present invention can execute the battery balancing control method provided by the embodiment of the present invention, and the implementation principle is similar. The actions executed by each module and unit in the battery balancing control system in each embodiment of the present invention correspond to the steps in the battery balancing control method in each embodiment of the present invention. For the detailed functional description of each module of the battery balancing control system, please refer to the description of the corresponding battery balancing control method shown in the foregoing text, which will not be repeated here.

[0104] The battery balancing control system may be a computer program (including program code) running in a computer device. For example, the battery balancing control system is an application software. The application software may be used to execute the corresponding steps in the method provided in the embodiment of the present invention.

[0105] In some embodiments, the battery balancing control system provided by the embodiment of the present invention may be implemented in a combination of software and hardware. As an example, the battery balancing control system provided by the embodiment of the present invention may be a processor in the form of a hardware decoding processor, which is programmed to execute the battery balancing control method provided by the embodiment of the present invention. For example, the processor in the form of a hardware decoding processor may be one or more application specific integrated circuits (ASICs), DSPs, programmable logic devices (PLDs), complex programmable logic devices (CPLDs), field programmable gate arrays (FPGAs), or other electronic components.

[0106] The modules involved in the embodiments of the present invention may be implemented by software or hardware, wherein the name of a module does not limit the module itself in some cases.

[0107] Based on the same principle as the method shown in the embodiments of the present invention, an electronic device is also provided in the embodiments of the present invention, which may include but is not limited to: a processor and a memory; the memory is used to store a computer program; the processor is used to execute the method shown in any embodiment of the present invention by calling the computer program.

[0108] In an alternative embodiment, an electronic device is provided, such as Figure 2 As shown, Figure 2 The electronic device shown includes: a processor and a memory. The processor and the memory are connected, such as through a bus. Optionally, the electronic device may also include a transceiver, which may be used for data exchange between the electronic device and other electronic devices, such as data transmission and / or data reception. It should be noted that in actual applications, the transceiver is not limited to one, and the structure of the electronic device does not constitute a limitation on the embodiments of the present invention.

[0109] The processor may be a CPU (Central Processing Unit), a general-purpose processor, a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. It may implement or execute various exemplary logic blocks, modules and circuits described in conjunction with the disclosure of the present invention. The processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, etc.

[0110] The bus may include a path to transmit information between the above components. The bus may be a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 2 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0111] The memory can be ROM (Read Only Memory) or other types of static storage devices that can store static information and instructions, RAM (Random Access Memory) or other types of dynamic storage devices that can store information and instructions, or it can be EEPROM (Electrically Erasable Programmable Read Only Memory), CD-ROM (Compact Disc Read Only Memory) or other optical disk storage, optical disk storage (including compressed optical disk, laser disc, optical disk, digital versatile disc, Blu-ray disc, etc.), magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited to this.

[0112] The memory is used to store the application code (computer program) for executing the solution of the present invention, and the execution is controlled by the processor. The processor is used to execute the application code stored in the memory to implement the content shown in the above method embodiment.

[0113] The electronic device may also be a terminal device. Figure 2 The electronic device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0114] An embodiment of the present invention provides a computer-readable storage medium, on which a computer program is stored. When the computer-readable storage medium is run on a computer, the computer can execute the corresponding contents of the aforementioned method embodiment.

[0115] According to another aspect of the present invention, a computer program product or a computer program is also provided, the computer program product or the computer program comprising computer instructions, the computer instructions being stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device executes the methods provided in the implementation modes of the above-mentioned various embodiments.

[0116] Computer program code for performing the operations of the present invention may be written in one or more programming languages, or a combination thereof, including object-oriented programming languages, such as Java, Smalltalk, C++, and conventional procedural programming languages, such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., through the Internet using an Internet service provider).

[0117] It should be understood that the flow charts and block diagrams in the accompanying drawings illustrate the possible implementation architecture, functions and operations of the method and computer program product according to various embodiments of the present invention. In this regard, each box in the flow chart or block diagram can represent a module, a program segment, or a part of a code, and the module, the program segment, or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a sequence different from that marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flow chart, and the combination of the boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0118] The computer-readable storage medium provided by the embodiment of the present invention may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to, an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present invention, a computer-readable storage medium may be any tangible medium containing or storing a program that may be used by or in conjunction with an instruction execution system, device, or device.

[0119] The computer-readable storage medium carries one or more programs. When the one or more programs are executed by the electronic device, the electronic device executes the method shown in the above embodiment.

[0120] The above description is only a preferred embodiment of the present invention and an explanation of the technical principles used. Those skilled in the art should understand that the disclosure scope involved in the present invention is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the above disclosed concept. For example, the above features are replaced with the technical features with similar functions disclosed in the present invention (but not limited to) by each other.

Claims

1. A battery balancing control method, characterized in that: include: Acquire the attribute data of the battery pack in real time, wherein the attribute data includes temperature, voltage and SOC; Based on the attribute data, using the BMS to determine in real time whether the battery pack meets the balancing circuit start condition, if not, not starting the balancing circuit, if yes, starting the balancing circuit to balance the battery pack; After the balancing circuit is turned on, the BMS is used to determine in real time whether the battery pack has reached the balancing circuit closing condition. If so, the balancing circuit is closed. If not, the process returns to continue determining whether the battery pack has reached the balancing circuit closing condition.

2. A battery balancing control method according to claim 1, characterized in that: Based on the voltage and SOC of the single cell in the battery pack, a V-SOC characteristic curve of the single cell is generated, and the stable stage of the single cell is divided into a plateau period and a non-plateau period according to the V-SOC characteristic curve, and the SOC in the range of [20%, 80%) is defined as the plateau period, and the SOC in the range of [0, 20%) or [80%, 100%) is defined as the non-plateau period.

3. A battery balancing control method according to claim 2, characterized in that: The equalization circuit start-up condition includes the following sub-conditions: A difference ΔSOC between a maximum SOC and a minimum SOC of a single battery in the battery pack is between a first SOC threshold and a second SOC threshold; The difference ΔV between the highest voltage and the lowest voltage of the single battery in the battery pack is greater than the voltage threshold, and both the single battery with the highest voltage and the single battery with the lowest voltage are in a non-plateau period; The highest battery temperature of the single battery in the battery pack is greater than T0℃; The PackSOC of the battery pack is greater than the PackSOC threshold; Each of the above sub-conditions is independently judged in real time, and when all sub-conditions are met, the equalization circuit start function is triggered.

4. A battery balancing control method according to claim 3, characterized in that: The balancing circuit shutdown condition includes the following sub-conditions: The difference ΔSOC between the highest SOC and the lowest SOC of the single battery in the battery pack is less than or equal to the first SOC threshold or the difference ΔSOC is greater than or equal to the second SOC threshold The difference ΔV between the highest voltage and the lowest voltage of the single battery in the battery pack is less than or equal to the voltage threshold, and the single battery with the highest voltage and the single battery with the lowest voltage are both in the plateau phase; The maximum battery temperature of the single battery in the battery pack is less than or equal to T0℃; The PackSOC of the battery pack is less than or equal to the PackSOC threshold; Each of the above sub-conditions is independently judged in real time, and when any of the sub-conditions is met, the balancing circuit shutdown function is triggered.

5. The battery balancing control method according to claim 1, characterized in that: The balancing adjustment of the battery pack is to calculate the balancing power required by each single battery in the battery pack, and then calculate the balancing time according to the balancing power, which specifically includes: The SOC of the single cells in the battery pack is obtained, and the single cell with the highest SOC is used as the reference single cell. The SOC of other single cells in the battery pack is compared with the SOC of the reference single cell to obtain the balanced power required by each single cell. The formula for calculating the balanced power is: ΔQ=C×(SOC ref -SOC i ) Among them, C represents the rated capacity of the single battery, SOC ref Indicates the SOC of the reference single battery, SOC i Represents the SOC of the i-th single cell; The formula for calculating the balancing time according to the balancing power is: Among them, I bal Indicates the maximum balancing current of the balancing circuit.

6. A battery balancing control method according to claim 1, characterized in that: Also includes: The BMS starts or shuts down the balancing circuit through an electronic switch located between the single battery and the balancing circuit; when the electronic switch is turned on, the balancing circuit starts to work, and when the electronic switch is turned off, the balancing circuit stops working.

7. The battery balancing control method according to claim 1, characterized in that: Also includes: When the balancing circuit is turned on, the BMS is used to obtain the circuit board temperature of the PCB board carrying the balancing circuit. When the circuit board temperature is less than T1°C, the balancing channel of the balancing circuit is in a fully open state; when the circuit board temperature is greater than or equal to T1°C and less than T2°C, the balancing channel of the balancing circuit is closed by half; when the circuit board temperature is greater than or equal to T2°C and less than T3°C, the balancing channel of the balancing circuit is closed by two-thirds, and when the circuit board temperature is greater than or equal to T3°C, the balancing circuit is turned off.

8. A battery balancing control system, characterized in that: The battery balancing control system is implemented based on a battery pack, a balancing circuit and a BMS, and specifically includes: A battery pack, which has multiple single cells connected in series; The BMS, connected with the battery pack, comprises: A data acquisition unit, used for acquiring attribute data in the battery pack in real time, the attribute data including temperature, voltage and SOC; a condition determination unit, used for determining in real time whether the battery pack meets the equalization circuit start-up condition based on the attribute data, if not, not turning on the equalization circuit, if yes, turning on the equalization circuit to perform equalization adjustment on the battery pack; and also used for determining in real time whether the battery pack meets the equalization circuit shutdown condition after the equalization circuit is turned on, if yes, turning off the equalization circuit, if no, returning to continue determining whether the battery pack meets the equalization circuit shutdown condition; The balancing circuit is connected between the battery pack and the BMS and is used to balance the SOC of each single battery in the battery pack.

9. An electronic device, characterized in that: The method comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method according to any one of claims 1 to 7 when executing the computer program.

10. A computer storage medium, characterized in that: The computer storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

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