Battery cell isolation and recovery method and device of battery pack, equipment and storage medium

Abstract

The invention discloses a battery cell isolation and recovery method, device and equipment of a battery pack and a storage medium, relates to the technical field of battery fault control, and discloses the battery cell isolation and recovery method of the battery pack, which comprises the following steps: when a battery cell abnormal instruction exists, determining the running state of a battery management system, abnormal circuit isolation is carried out according to the operation state of the battery management system to obtain an abnormal battery cell state and a power-on main circuit; determining a target valve opening degree according to the abnormal battery cell state, and controlling the opening degree of a heat dissipation control assembly according to the target valve opening degree so as to cool the abnormal battery cell to obtain a cooled battery cell; performing health assessment according to the operation states of the cooled battery cell and the battery management system to obtain a health assessment result; and according to the health assessment result, abnormal battery cell recovery is carried out on the cooled battery cell to obtain a recovered battery cell, and the recovered battery cell is connected to a power-on main circuit to complete battery cell isolation and recovery of the battery pack. Accurate fault handling, efficient temperature control and safe recovery of the battery pack cell are realized.

Description

Technical Field

[0001] This application relates to the field of battery fault control technology, and in particular to cell isolation and recovery methods, apparatus, equipment and storage media for battery packs. Background Technology

[0002] With the increasing prevalence of high-energy-density batteries, the risks of thermal runaway caused by internal short circuits, electrode damage, and material aging within the battery cell are showing an increasing trend. To ensure vehicle safety, various detection units are typically configured to monitor operating conditions such as voltage, temperature, internal resistance, and current, while relying on the battery management system for status identification, anomaly warnings, and basic protection measures. However, cell-level risks are usually characterized by rapid changes, strong propagation, and irreversibility. If not handled promptly or accurately, they can easily lead to heat dissipation, entire battery pack failure, or even vehicle safety accidents.

[0003] Against this industry backdrop, traditional technologies generally employ a control approach focused on protecting the entire battery pack. This involves limiting power, stopping charging and discharging, and implementing pack-level heat dissipation to address cell anomalies and prevent further deterioration. While such solutions can mitigate dangerous trends to some extent, their limited scope makes it difficult to address rapidly changing cell conditions with finer-grained and flexible measures. Furthermore, they lack the capacity for in-depth condition assessment and subsequent processing after the anomaly has subsided.

[0004] The above content is only used to help understand the technical solution of this application and does not represent an admission that the above content is prior art. Summary of the Invention

[0005] The main objective of this application is to provide a method, apparatus, device, and storage medium for cell isolation and recovery of a battery pack, aiming to solve the technical problem of how to achieve more timely, accurate, and safe handling without affecting the normal power supply of the vehicle when a cell malfunctions.

[0006] To achieve the above objectives, this application proposes a method for cell isolation and recovery in a battery pack, the method comprising: When a cell malfunction command is received, the operating status of the battery management system is determined, and the abnormal circuit is isolated according to the operating status of the battery management system to obtain the abnormal cell status and the power-on main circuit. The target valve opening is determined based on the abnormal cell state, and the opening of the heat dissipation control component is controlled based on the target valve opening to cool down the abnormal cell and obtain a cooled cell. A health assessment is performed based on the operating status of the cooled battery cell and the battery management system to obtain the health assessment results. Based on the health assessment results, the abnormal battery cell is restored to a recovered battery cell, and the recovered battery cell is connected to the main power circuit to complete the battery pack's cell isolation and restoration.

[0007] In addition, to achieve the above objectives, this application also proposes a cell isolation and recovery device for a battery pack. The cell isolation and recovery device for the battery pack includes: an anomaly detection module, used to determine the operating state of the battery management system when there is a cell anomaly command, and to isolate the abnormal circuit according to the operating state of the battery management system to obtain the abnormal cell state and the power-on main circuit. A cell cooling module is used to determine the target valve opening degree based on the abnormal cell state, and control the opening degree of the heat dissipation control component based on the target valve opening degree, so as to cool down the abnormal cell and obtain a cooled cell. The health assessment module is used to perform a health assessment based on the operating status of the cooling battery cell and the battery management system, and obtain the health assessment result. The cell recovery module is used to recover abnormal cells from the cooled cells based on the health assessment results, obtain recovered cells, and connect the recovered cells to the power-on main circuit to complete the cell isolation and recovery of the battery pack.

[0008] In addition, to achieve the above objectives, this application also proposes a cell isolation and recovery device for a battery pack, the device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the cell isolation and recovery method for the battery pack as described above.

[0009] In addition, to achieve the above objectives, this application also proposes a storage medium, which is a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the steps of the battery pack cell isolation and recovery method described above.

[0010] In addition, to achieve the above objectives, this application also provides a computer program product, which includes a computer program that, when executed by a processor, implements the steps of the battery pack cell isolation and recovery method described above.

[0011] One or more technical solutions proposed in this application have at least the following technical effects: By employing a technique that determines the battery management system's operating state upon the presence of a cell anomaly command, isolates the abnormal circuit based on this state to obtain the abnormal cell's status and the main power circuit, determines the target valve opening based on the abnormal cell's status, and controls the opening of the heat dissipation control components to cool the abnormal cell, a cooled cell is obtained. Next, a health assessment is performed based on the cooled cell and the battery management system's operating state to obtain a health assessment result. Based on the health assessment result, the cooled cell is restored to its normal state, resulting in a restored cell, which is then connected to the main power circuit. This technique, by implementing abnormal circuit isolation according to the battery management system's operating state, achieves precise separation of the abnormal cell from the main power circuit while maintaining continuous conduction of the main power circuit. This avoids the vehicle's interruption caused by abruptly cutting off power, as is common in existing technologies, and also blocks the risk propagation path of the abnormal cell. Furthermore, it allows for targeted determination of the target valve opening based on the abnormal cell's status. By controlling the valve opening and the operation of the heat dissipation control components, targeted and precise cooling of abnormal battery cells is achieved, overcoming the shortcomings of traditional fixed-flow heat dissipation which cannot quickly interrupt thermal chain reactions. Through coherent control of health assessment and abnormal battery cell restoration, qualified cooled battery cells can be safely returned to the main power circuit, avoiding the waste of repairable cells. Corresponding operations are implemented in conjunction with the battery management system's operating status during abnormal circuit isolation and health assessment, filling the control gap after battery management system failure and ensuring the normal operation of the battery circuit under different battery management system operating states. Compared with existing technologies, this technology achieves precise handling, efficient cooling, and safe recovery of abnormal battery cells, improving the operational safety and reliability of the battery pack, avoiding secondary accidents in extreme scenarios, extending the battery pack's service life, ensuring vehicle driving continuity, and enhancing the practicality of the control. Attached Figure Description

[0012] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0013] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 A flowchart illustrating the cell isolation and recovery method for the battery pack of this application (Example 1). Figure 2 A schematic diagram of the anomaly identification process provided in Embodiment 1 of the battery pack cell isolation and recovery method of this application; Figure 3 A schematic diagram of the isolation control process provided in Embodiment 1 of the battery pack cell isolation and recovery method of this application; Figure 4 A schematic diagram of the heat dissipation control process provided in Embodiment 1 of the battery pack cell isolation and recovery method of this application; Figure 5 A schematic diagram of the cell recovery process provided in Embodiment 1 of the cell isolation and recovery method for the battery pack of this application; Figure 6 A flowchart illustrating Embodiment 2 of the battery pack cell isolation and recovery method of this application; Figure 7 This is a simplified flowchart illustrating the cell isolation and recovery method for the battery pack provided in Embodiment 2 of this application. Figure 8 This is a schematic diagram of the module structure of the cell isolation and recovery device for the battery pack in an embodiment of this application; Figure 9 This is a schematic diagram of the equipment structure of the hardware operating environment involved in the cell isolation and recovery method of the battery pack in the embodiments of this application.

[0015] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0016] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.

[0017] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0018] The main solution of this application embodiment is as follows: When a cell abnormality command is present, the operating state of the battery management system is determined, and abnormal circuit isolation is performed according to the operating state of the battery management system to obtain the abnormal cell state and the power-on main circuit; the target valve opening is determined according to the abnormal cell state, and the opening of the heat dissipation control component is controlled according to the target valve opening to cool down the abnormal cell and obtain a cooled cell; a health assessment is performed based on the cooled cell and the operating state of the battery management system to obtain a health assessment result; the abnormal cell is restored based on the health assessment result to obtain a restored cell, and the restored cell is connected to the power-on main circuit to complete the cell isolation and restoration of the battery pack.

[0019] In this embodiment, for ease of description, the following description will focus on the battery pack cell isolation and recovery device as the main execution subject.

[0020] To address the limitations of existing technologies in achieving timely, accurate, and safe handling of battery cell malfunctions without disrupting vehicle power supply, this application provides a solution. This solution employs a method that, upon receiving a battery cell malfunction command, determines the operating status of the battery management system (BMS) and isolates the abnormal circuit based on this status to obtain the abnormal cell's state and the main power circuit. Then, based on the abnormal cell's state, it determines the target valve opening and controls the opening of the heat dissipation control components to cool the abnormal cell, resulting in a cooled cell. Next, it performs a health assessment based on the cooled cell and the BMS operating status to obtain a health assessment result. Based on the health assessment result, it restores the cooled cell to its normal operating state and connects it to the main power circuit. By isolating the abnormal circuit according to the BMS operating status, this method achieves precise separation of the abnormal cell from the main power circuit while maintaining continuous conduction of the main power circuit. This avoids the vehicle interruption caused by abruptly cutting off power, as is common in existing technologies, and also prevents... This technology effectively mitigates the risk propagation path of abnormal battery cells. It determines the target valve opening based on the abnormal cell's condition and controls the operation of the heat dissipation control components, achieving targeted and precise cooling of abnormal cells and overcoming the limitation of traditional fixed-flow heat dissipation methods that cannot quickly interrupt thermal chain reactions. Through coherent control of health assessment and abnormal cell restoration, it allows eligible cooled cells to safely return to the main power circuit, avoiding waste of repairable cells. In both abnormal circuit isolation and health assessment stages, corresponding operations are implemented in conjunction with the battery management system's operating status, filling the control gap after battery management system failure and ensuring the normal operation of the battery circuit under different battery management system operating states. Compared with existing technologies, this technology achieves precise handling, efficient cooling, and safe recovery of abnormal battery cells, improving the operational safety and reliability of the battery pack, preventing secondary accidents in extreme scenarios, extending battery pack lifespan, ensuring vehicle driving continuity, and enhancing control practicality.

[0021] It should be noted that the executing entity in this embodiment can be a computing service device with data processing, network communication, and program execution functions, such as a tablet computer, personal computer, or mobile phone; or an electronic device capable of performing the above functions, a battery pack cell isolation and recovery device, or a battery management system. The following description uses a battery management system as an example to illustrate this embodiment and the subsequent embodiments.

[0022] Based on this, embodiments of this application provide a method for cell isolation and recovery of a battery pack, referring to... Figure 1 , Figure 1 This is a flowchart illustrating the first embodiment of the cell isolation and recovery method for the battery pack of this application.

[0023] In this embodiment, the cell isolation and recovery method of the battery pack includes steps S10~S40: Step S10: When there is a cell abnormality command, determine the operating status of the battery management system, and isolate the abnormal circuit according to the operating status of the battery management system to obtain the abnormal cell status and the power-on main circuit. It should be noted that the cell malfunction command is generated after a dual determination, which includes active determination and passive verification. When any condition of active determination or passive verification is met, it is generated by the main control module of the Battery Management System (BMS) to mark the number of the malfunctioning cell and start the subsequent isolation control process.

[0024] Additionally, abnormal circuit isolation is an operation performed to disconnect a faulty battery cell from the main circuit. Depending on the operating state of the battery management system, it is divided into active isolation and passive isolation. The purpose is to prevent the risk of the faulty cell from spreading while maintaining the continuity of the main circuit. Active isolation relies on commands sent by the BMS main control module, while passive isolation is triggered by the physical characteristics of a resettable fuse.

[0025] Furthermore, the abnormal cell state refers to the state in which the abnormal cell is physically separated from the main circuit after isolation. In this state, the abnormal cell no longer participates in the charging and discharging of the main circuit, and will undergo subsequent cooling and health assessment. This state not only prevents the spread of risk, but also leaves room for subsequent cell handling.

[0026] Additionally, the main power circuit is a series circuit consisting of all normal battery cells in the battery pack, excluding the faulty cells. This circuit remains conductive throughout the isolation process for faulty circuits, ensuring the vehicle can receive normal power. Regardless of whether active or passive isolation is used, this circuit will not experience any momentary power outages.

[0027] Understandably, when a cell malfunction command is received, the system first determines whether the battery management system is operating normally or malfunctioning, and then performs active or passive isolation operations accordingly. Ultimately, this achieves physical separation of the malfunctioning cell from the main circuit, while simultaneously obtaining the status of the malfunctioning cell and maintaining the conducting main circuit.

[0028] In one feasible implementation, steps S01 to S02 may be included before step S10: Step S01: Obtain cell temperature data, temperature change rate data, cell voltage data, cell internal resistance data, circuit current data, abnormal temperature threshold, second abnormal temperature threshold, temperature change rate threshold, cell voltage change threshold, cell internal resistance change threshold, and instantaneous short-circuit current threshold. It should be noted that the cell temperature data reflects the real-time heating status of the cell, which is obtained by the temperature sensor in real time and can intuitively show the current thermal state of the cell.

[0029] Additionally, the temperature change rate data refers to the change in cell temperature per unit time, i.e., dT / dt. It is calculated by continuously collecting temperature data from the temperature sensor and can quickly capture sudden changes in cell temperature, thus promptly detecting early signs of thermal runaway.

[0030] Furthermore, the cell voltage data is an electrical parameter that reflects the charging and discharging state of the cell. It is collected in real time by a voltage sampling chip and covers the voltage values ​​during the charging and discharging process. Its sudden changes can reflect whether there are abnormalities such as short circuits or attenuation inside the cell.

[0031] In addition, the internal resistance data of the battery cell is a parameter that reflects the internal conductivity of the battery cell. It is monitored and obtained by the internal resistance detection unit. When problems such as micro-short circuits or aging occur inside the battery cell, the internal resistance will change significantly. It is an important indicator for assessing the health status of the battery cell.

[0032] Furthermore, loop current data refers to the magnitude of the current flowing in the series loop of the battery pack, which is monitored and obtained by the current sensor of the passive control component. It can reflect the conduction status of the loop, and an abnormal increase usually means that there are serious problems such as short circuits in the battery cells.

[0033] In addition, the abnormal temperature threshold is the temperature limit for judging whether there is a thermal abnormality in the battery cell. It varies depending on the type of battery cell. The abnormal temperature threshold for ternary lithium is 70 degrees Celsius, and the abnormal temperature threshold for lithium iron phosphate is 85 degrees Celsius. When the battery cell temperature data reaches or exceeds this threshold, it is judged as a temperature abnormality.

[0034] Furthermore, the second abnormal temperature threshold is the temperature limit used for subsequent heat dissipation control. Corresponding to the abnormal temperature threshold, the second abnormal temperature threshold for ternary lithium is 70 degrees Celsius, and for lithium iron phosphate it is 85 degrees Celsius. It is a key point to distinguish between basic heat dissipation and centralized heat dissipation.

[0035] In addition, the temperature change rate threshold is the boundary value for judging whether the temperature change is abnormal. It is set to 5 degrees Celsius per minute. When the temperature change rate data reaches or exceeds this value, it indicates that the cell temperature is rising too fast and there is a risk of thermal runaway, which needs to trigger an abnormal judgment.

[0036] Furthermore, the cell voltage change threshold is the standard for judging whether the cell voltage has changed abnormally. It is divided into two scenarios: charging and discharging. The voltage drop threshold during charging is 0.1 volts, and the voltage rise threshold during discharging is 0.05 volts. Exceeding this threshold is considered an abnormal voltage.

[0037] In addition, the threshold for changes in the internal resistance of the battery cell is the standard for judging whether the internal resistance of the battery cell has changed abnormally. It is set to change by 30% compared with the historical baseline. When the change in the internal resistance data of the battery cell reaches or exceeds this proportion, it indicates that there may be an abnormality in the internal structure of the battery cell, and an abnormality judgment needs to be triggered.

[0038] Furthermore, the instantaneous short-circuit current threshold is the current limit for determining whether a circuit has an instantaneous short circuit. It is set to 10 times the rated current. When the circuit current data exceeds this threshold, regardless of whether other parameters are normal, it is determined to be a short circuit abnormality, triggering passive verification.

[0039] Understandably, data acquisition components such as temperature sensors, voltage sampling chips, internal resistance detection units, and current sensors are used to obtain cell temperature data, temperature change rate data, cell voltage data, cell internal resistance data, and circuit current data, respectively. At the same time, based on the cell type and battery pack design parameters, abnormal temperature threshold, second abnormal temperature threshold, temperature change rate threshold, cell voltage change threshold, cell internal resistance change threshold, and instantaneous short-circuit current threshold are determined and obtained, providing complete data support and judgment criteria for subsequent cell anomaly determination.

[0040] Step S02: When the battery pack cells meet any one of the following conditions: whether the cell temperature data exceeds the abnormal temperature threshold, whether the temperature change rate data exceeds the temperature change rate threshold, whether the cell voltage data change exceeds the cell voltage change threshold, whether the cell internal resistance data change exceeds the cell internal resistance change threshold, or whether the circuit current data exceeds the instantaneous short-circuit current threshold, a cell abnormality command is generated.

[0041] It should be noted that the cell anomaly command is used to mark a cell as having an anomaly and initiate subsequent isolation control procedures. Its generation is based on the fulfillment of multiple anomaly judgment conditions. If any one of these conditions is met, it indicates a safety risk to the cell, requiring immediate triggering of subsequent handling procedures. In this embodiment, a cell in the ternary lithium battery pack meets the conditions of temperature data compliance and internal resistance mutation, while a cell in the lithium iron phosphate battery pack meets the condition of excessive circuit current; both of these conditions generate the command.

[0042] Understandably, the acquired cell temperature data is compared with abnormal temperature thresholds, temperature change rate data with temperature change rate thresholds, cell voltage change data with cell voltage change thresholds, cell internal resistance change data with cell internal resistance change thresholds, and loop current data with instantaneous short-circuit current thresholds. If the temperature data of a cell in a ternary lithium battery pack reaches 70 degrees Celsius, exceeding the abnormal temperature threshold, and its internal resistance data changes abruptly by 35% from the historical baseline, exceeding the cell internal resistance change threshold, satisfying either condition, a cell abnormality command is generated. Similarly, if the loop current data of a cell in a lithium iron phosphate battery pack reaches 1800 amperes, exceeding the instantaneous short-circuit current threshold, satisfying the condition, a cell abnormality command is generated. If any of the above comparison results exceeds a threshold, the cell is determined to be abnormal, and a cell abnormality command is generated. (Refer to...) Figure 2 , Figure 2This is a schematic diagram of the anomaly identification process in the first embodiment of the cell isolation and recovery method for the battery pack of this application.

[0043] like Figure 2 As shown, starting from the input of the multi-parameter acquisition module, this module collects data such as cell temperature T, temperature change rate dT / dt, cell voltage U, cell internal resistance R, and loop current I. This data is sent to the active judgment algorithm for analysis. The active judgment algorithm checks whether any abnormal condition is met, such as whether the cell temperature T reaches or exceeds the set abnormal temperature threshold, whether the temperature change rate dT / dt is too fast, whether the cell voltage U drops or rises suddenly, and whether the cell internal resistance R changes abruptly from the historical baseline. If any condition is met, an abnormal command is triggered, entering stage two rapid isolation. If the active judgment algorithm does not trigger an abnormal command, the passive verification logic is entered, checking whether the loop current I reaches or exceeds 10 times the rated current, i.e., whether a momentary short circuit has occurred. If the current exceeds 10 times the rated value, the cell internal resistance R will serve as an abnormal trigger condition, triggering an abnormal command and also entering stage two rapid isolation. Through both active judgment and passive verification, accurate identification of abnormal cell states is ensured, laying the foundation for subsequent rapid isolation control.

[0044] In one feasible implementation, step S10 may include steps S11-S12: Step S11: When the battery management system is determined to be in normal operation, a first control command and a second control command are sent to the high-voltage switch assembly of the abnormal cell, so that the high-voltage switch assembly controls the solid-state relay to disconnect according to the first control command and controls the dual redundant backup branch to conduct according to the second control command, so as to isolate the abnormal circuit and obtain the abnormal cell status and the main power-on circuit. It should be noted that the first control command is used to control the solid-state relay in the high-voltage switchgear to disconnect, physically separating the faulty cell from the main circuit. It is the core disconnect command in active isolation control. This command has a fast response time, enabling rapid disconnection and allowing sufficient time for the subsequent dual-redundant backup branch to be turned on, ensuring uninterrupted circuit operation.

[0045] Additionally, the second control command, sent synchronously with the first control command, is used to control the conduction of the dual redundant backup branch in the high-voltage switchgear assembly, establishing a temporary current flow path to prevent momentary power outages after the solid-state relay disconnects. The dual redundant backup branch has reliable conduction performance and can withstand the circuit's rated current, ensuring uninterrupted power supply to the vehicle.

[0046] Furthermore, the high-voltage switch assembly is a component of the cell-level control execution module, integrating a solid-state relay and dual redundant backup circuits. It can receive and execute control commands sent by the BMS main control module, enabling the connection or disconnection of abnormal cells from the main circuit, while ensuring circuit continuity through the backup circuits. In this embodiment, each cell in the ternary lithium battery pack is equipped with this assembly, ensuring precise execution of active isolation.

[0047] Furthermore, solid-state relays are key components in high-voltage switchgear for circuit switching. They are characterized by fast response speed and high reliability, enabling rapid response to the first control command to disconnect abnormal cells from the main circuit. Their disconnection action and the conduction action of the dual-redundant backup branch strictly adhere to timing requirements. In this embodiment, the response time of the solid-state relay is 5 milliseconds, ensuring timely control.

[0048] Furthermore, the dual-redundant backup branch is a backup conduction path in the high-voltage switch assembly, which is set in parallel with the solid-state relay. When the solid-state relay is disconnected, this branch can be turned on in time according to the second control command to take over the circuit current and maintain the continuous conduction of the series circuit, so as to prevent the vehicle from being unable to drive due to the circuit power failure.

[0049] Understandably, when the battery management system (BMS) is determined to be operating normally, the BMS main control module simultaneously sends a first control command and a second control command to the high-voltage switch assembly of the faulty cell. The high-voltage switch assembly controls the solid-state relay to disconnect according to the first control command, and simultaneously controls the dual-redundant backup branch to conduct according to the second control command, with the time difference between the solid-state relay disconnection and the dual-redundant backup branch conduction not exceeding 10 milliseconds.

[0050] Step S12: When it is determined that the battery management system is in a failed state, the passive control component corresponding to the target cell is controlled to perform passive abnormal circuit isolation to obtain the abnormal cell state and the power-on main circuit.

[0051] It should be noted that the passive control component is part of the cell-level control execution module, comprising a resettable fuse and a metal current-conducting plate. It does not rely on active commands from the BMS main control module and can automatically trigger isolation and freewheeling operations based on abnormal changes in the loop current. It is a core control component in BMS failure scenarios. In this embodiment, the resettable fuse in this component of the lithium iron phosphate battery pack has an operating temperature of 100 degrees Celsius, and the conductive cross-section of the metal current-conducting plate is 10 square millimeters, ensuring reliable execution of the passive control.

[0052] In addition, passive abnormal circuit isolation refers to the automatic isolation of abnormal cells from the main circuit based on the physical characteristics of passive control components when the BMS fails. This requires no manual intervention or BMS commands and can quickly respond to anomalies after BMS failure, preventing the spread of risk. This isolation method is achieved through a sudden change in the resistance of a self-resetting fuse and is an important safety precaution for ensuring battery pack safety.

[0053] Understandably, when the battery management system is determined to be in a failed state, an internal short circuit in the abnormal cell will cause a sudden increase in circuit current. The resettable fuse in the passive control component will overheat due to overcurrent, exceeding its operating temperature. The operating temperature for ternary lithium batteries is 85 degrees Celsius, and for lithium iron phosphate batteries, it is 100 degrees Celsius. The resistance of the resettable fuse will jump from a few milliohms to several thousand ohms, achieving an equivalent circuit break and automatically isolating the abnormal circuit. Simultaneously, the current will automatically switch to flow through the parallel metal conductor, maintaining the series circuit continuity. (Refer to...) Figure 3 , Figure 3 This is a schematic diagram of the isolation control process of the first embodiment of the cell isolation and recovery method for the battery pack of this application.

[0054] like Figure 3 As shown, starting from receiving an abnormal command, the system first checks the BMS status. If the BMS status is normal, active isolation control is executed, sending commands to disconnect the solid-state relay and connect the backup branch, ensuring a time difference of less than or equal to 10 milliseconds to avoid instantaneous power outages. If the BMS status is abnormal, passive isolation control is executed. The self-resetting fuse overheats, causing its resistance to jump to several thousand ohms, effectively breaking the circuit and automatically triggering passive isolation. Simultaneously, the current automatically switches to flow through the parallel metal conductor, maintaining the series circuit continuity. Whether active or passive isolation is used, the circuit remains conductive. The process then enters stage three, focusing on heat dissipation. In this stage, the system dynamically adjusts the heat dissipation power based on the cell temperature to improve cooling efficiency, thereby effectively controlling the battery pack temperature and preventing thermal runaway. This process ensures rapid and effective isolation when a cell malfunctions, while maintaining continuous power supply to the battery pack, improving the safety and reliability of new energy vehicles.

[0055] Step S20: Determine the target valve opening degree based on the abnormal cell state, and control the opening degree of the heat dissipation control component based on the target valve opening degree to cool down the abnormal cell and obtain a cooled cell. It should be noted that the target valve opening degree is determined based on the real-time temperature data of the abnormal battery cell, and is divided into two levels: 30% opening and 100% opening, corresponding to different heat dissipation requirements to achieve precise cooling. 30% opening corresponds to basic heat dissipation, while 100% opening corresponds to concentrated heat dissipation, adapting to different temperature ranges.

[0056] Additionally, the heat dissipation control component is integrated into the cell-level control execution module. It includes solenoid valves and a miniature liquid-cooled flow channel interface, capable of receiving control commands to adjust the valve opening, allowing the faulty cell to connect to the main liquid cooling system for heat dissipation. The miniature liquid-cooled flow channel interface ensures that the coolant flows precisely through the faulty cell to remove heat.

[0057] Furthermore, a cooled battery cell refers to an abnormal battery cell whose temperature drops to a preset safe range after being cooled by the heat dissipation control component according to the target valve opening degree, and whose temperature state meets the basic conditions for subsequent health assessment. After cooling, the battery cell temperature stabilizes between 25 and 45 degrees Celsius, providing a suitable temperature environment for health assessment.

[0058] Understandably, based on the real-time temperature data obtained from the abnormal cell status, the corresponding target valve opening is determined, and then the heat dissipation control component is controlled to operate at that opening to dissipate heat in a targeted manner on the abnormal cell, ultimately resulting in a cooled cell that meets the temperature standard.

[0059] In one feasible implementation, step S20 may include steps S21 to S23: Step S21: Obtain the cell temperature, first preset temperature threshold, second preset temperature threshold, first valve opening, second valve opening, first coolant flow rate, and second coolant flow rate of the abnormal cell, wherein the first preset temperature threshold is less than the second preset temperature threshold, the first valve opening is less than the second valve opening, and the first coolant flow rate is less than the second coolant flow rate. It should be noted that the cell temperature of the abnormal cell refers to the real-time temperature data of the abnormal cell after isolation. It is continuously monitored and acquired by a temperature sensor and can reflect the thermal state changes of the abnormal cell. It is the core basis for subsequently determining the target valve opening.

[0060] Additionally, the first preset temperature threshold, set at 45 degrees Celsius, is the temperature standard for distinguishing whether basic cooling should be activated. This threshold is lower than the second preset temperature threshold. When the abnormal cell temperature exceeds this value but does not reach the second preset temperature threshold, the basic cooling mode is activated. This threshold setting is based on the normal operating temperature range of the cell, which avoids excessive heat dissipation and energy waste while also being able to respond promptly to minor temperature anomalies.

[0061] Furthermore, the second preset temperature threshold is a key temperature standard that distinguishes between basic heat dissipation and concentrated heat dissipation. It is set differently depending on the cell type: 70 degrees Celsius for ternary lithium batteries and 85 degrees Celsius for lithium iron phosphate batteries. When the temperature reaches or exceeds this threshold, high-intensity concentrated heat dissipation must be initiated. This threshold setting is tailored to the thermal stability characteristics of different cell types, ensuring rapid cooling in the initial stages of thermal runaway.

[0062] Additionally, the first valve opening is the degree to which the solenoid valve is opened in the basic cooling mode, and it is set to 30%. This opening is less than the second valve opening, which can control the coolant to flow at a lower flow rate, achieving basic cooling while saving energy.

[0063] Furthermore, the second valve opening is the degree of opening of the solenoid valve in the centralized heat dissipation mode, which is set to 100%. This opening allows the coolant to pass through the micro liquid cooling channel at maximum flow rate, achieving efficient cooling and quickly removing a large amount of heat from the abnormal battery cell.

[0064] In addition, the first coolant flow rate is the coolant flow rate corresponding to the first valve opening, which is set to 1 liter per minute. This flow rate is less than the second coolant flow rate and is suitable for scenarios where the abnormal cell temperature is relatively low, so as to reduce the coolant circulation energy consumption while meeting the cooling requirements.

[0065] Furthermore, the second coolant flow rate is the coolant flow rate corresponding to the second valve opening, set at 3 liters per minute. This flow rate can maximize heat dissipation efficiency and is suitable for scenarios where abnormal cell temperatures are high and there is a risk of thermal runaway, quickly blocking thermal chain reactions.

[0066] Understandably, by continuously acquiring the cell temperature of abnormal cells through temperature sensors, and by pre-determining and acquiring the first preset temperature threshold, the second preset temperature threshold, the first valve opening, the second valve opening, the first coolant flow rate, and the second coolant flow rate based on the cell type and heat dissipation requirements, complete data support and execution standards are provided for subsequent temperature-based graded control of heat dissipation.

[0067] Step S22: When the cell temperature is greater than the first preset temperature threshold and less than the second preset temperature threshold, the target valve opening is determined to be the first valve opening, and the opening of the heat dissipation control component is controlled according to the target valve opening. The heat dissipation control component is controlled to operate with the first coolant flow rate to cool down the abnormal cell and obtain a cooled cell. Understandably, when the temperature of an abnormal battery cell is greater than the first preset temperature threshold but less than the second preset temperature threshold, it indicates a slight temperature anomaly in the cell, requiring no high-intensity heat dissipation. In this case, the target valve opening is determined to be the first valve opening. The heat dissipation control component is then controlled to open at the first valve opening and operate at the first coolant flow rate to perform basic cooling of the abnormal battery cell, ultimately resulting in a cooled battery cell with a stable temperature.

[0068] Step S23: When the cell temperature is greater than or equal to the second preset temperature threshold, the target valve opening is determined to be the second valve opening, and the opening of the heat dissipation control component is controlled according to the target valve opening. The heat dissipation control component is controlled to operate with the second coolant flow rate to cool down the abnormal cell and obtain a cooled cell.

[0069] Understandably, when the temperature of an abnormal battery cell is greater than or equal to the second preset temperature threshold, it indicates a high cell temperature and a risk of thermal runaway propagation, requiring the initiation of high-intensity centralized cooling. At this point, the target valve opening is determined to be the second valve opening. The cooling control component is then fully opened to the second valve opening and operates at the second coolant flow rate to rapidly cool the abnormal battery cell, ultimately resulting in a cooled battery cell with its temperature reduced to a safe range. (Refer to...) Figure 4 , Figure 4 This is a schematic diagram of the heat dissipation control process of the first embodiment of the cell isolation and recovery method for the battery pack of this application.

[0070] like Figure 4 As shown, starting from receiving an abnormal cell temperature T, the system first determines the temperature range. If temperature T is less than 45 degrees Celsius, cooling is not initiated. If temperature T is between 45 degrees Celsius and 70 or 85 degrees Celsius, the valve opening is 30%, and the flow rate is 1 liter per minute for basic cooling. If temperature T is greater than or equal to 70 or 85 degrees Celsius, the valve is 100% open, and the flow rate increases to 3 liters per minute for concentrated cooling. Under any cooling condition, the system continuously monitors the temperature. If temperature T decreases, monitoring continues until the temperature stops decreasing. In active isolation, cooling and isolation commands are sent synchronously with a response delay of less than 5 milliseconds. The entire process ensures that the abnormal cell is connected to the main liquid cooling system through a miniature liquid cooling channel, and the cooling power is dynamically adjusted according to the temperature to improve cooling efficiency. For example, the cooling time from 80 degrees Celsius to 60 degrees Celsius is controlled within 5 minutes. This process effectively controls the temperature of the battery pack by dynamically adjusting the heat dissipation power, preventing thermal runaway, while maintaining continuous power supply to the battery pack, thus improving the safety and reliability of new energy vehicles.

[0071] Step S30: Perform a health assessment based on the operating status of the cooled battery cell and the battery management system to obtain the health assessment result; It should be noted that health assessment is a process of continuously verifying multiple state data of the cooled battery cell through a health assessment algorithm. The verification parameters include temperature, voltage, internal resistance, and capacity decay rate, in order to determine whether the battery cell has the conditions for recovery.

[0072] In addition, the health assessment result is a judgment conclusion drawn after the health assessment, which is divided into two types: recoverable command and continuous isolation command, corresponding to the situation where the battery cell has the conditions for recovery and the situation where it does not have the conditions for recovery, respectively. The recoverable command triggers the subsequent precise access process, while the continuous isolation command maintains the existing isolation state.

[0073] Understandably, by combining the real-time status data of the cooled battery cells with the operating status of the battery management system, a health assessment algorithm is used to perform continuous verification of multiple parameters, ultimately generating a health assessment result that can be recovered or continuously isolated.

[0074] Step S40: Based on the health assessment results, perform abnormal cell recovery on the cooled battery cell to obtain a recovered battery cell, and connect the recovered battery cell to the power-on main circuit to complete the cell isolation and recovery of the battery pack.

[0075] It should be noted that the abnormal battery cell recovery process involves a series of operations based on the health assessment results, including pre-charge voltage regulation, closing the solid-state relay, disconnecting the backup branch, and power compensation. The aim is to safely return qualified cooled battery cells to the main circuit. The pre-charge voltage regulation process avoids current surges upon connection, while power compensation maintains stable vehicle power.

[0076] Additionally, a "recovered cell" refers to a cooled cell that has undergone a recovery operation after an abnormal cell failure, ensuring its voltage matches the series circuit voltage and its health status meets the requirements. Its parameters satisfy the requirements for normal operation when connected to a powered main circuit. The temperature, voltage, internal resistance, and capacity decay rate of the recovered cell are all within normal ranges, allowing it to participate in normal charging and discharging.

[0077] Understandably, based on the health assessment results, abnormal cell recovery operations are performed on the qualified cooled cells. After the recovered cells are obtained, they are connected to the main power circuit, thus completing the cell isolation and recovery process of the battery pack.

[0078] In one feasible implementation, step S40 may include steps S41 to S43: Step S41: When the health assessment result indicates that recovery is permissible, a pre-charge voltage regulation command is sent to the high-voltage switch assembly of the cooling cell, so that the high-voltage switch assembly starts the pre-charge voltage regulation circuit according to the pre-charge voltage regulation command to regulate the voltage of the cooling cell and feeds back the voltage of the cooling cell. It should be noted that the health assessment result that allows recovery is a judgment conclusion drawn after the health assessment. It is generated when the cooled battery cell simultaneously meets the following conditions: temperature stabilizes between 25 and 45 degrees Celsius, voltage recovers to the voltage range of the corresponding battery cell type, internal resistance falls back to within ±10% of the historical baseline, and capacity decay rate does not exceed 2% per 100 cycles. This indicates that the battery cell has the conditions to be safely connected to the main circuit.

[0079] Additionally, the pre-charge voltage regulation initiation command is sent from the BMS main control module to the high-voltage switch assembly. Its core function is to trigger the pre-charge voltage regulation circuit to operate, gradually adjusting the voltage of the cooled battery cell to reduce the voltage difference between it and the main energized circuit, thus preventing current surges upon direct connection. This command is sent synchronously with the health assessment results to ensure timely voltage regulation initiation.

[0080] Furthermore, the pre-charge voltage regulation circuit is a dedicated circuit in the high-voltage switch assembly used to regulate the cell voltage. It has the function of smooth voltage regulation and can gradually adjust the voltage of the cooling cell according to the voltage difference between the cooling cell and the main circuit, so that the two tend to be consistent.

[0081] In addition, the cooling cell voltage is a real-time electrical parameter of the abnormal cell after cooling. It is continuously monitored by the voltage sampling chip and fed back to the BMS main control module. This data is the basis for the adjustment of the pre-charge voltage regulation circuit, and its changes directly reflect the progress of voltage matching.

[0082] Understandably, when the health assessment result indicates that recovery is permissible, the BMS main control module sends a pre-charge voltage regulation command to the high-voltage switch assembly of the cooling cell. After receiving the command, the high-voltage switch assembly starts the pre-charge voltage regulation circuit to regulate the voltage of the cooling cell. At the same time, the voltage sampling chip monitors the voltage of the cooling cell in real time and feeds it back to the BMS main control module.

[0083] Step S42: Determine the target voltage difference between the voltage of the cooled battery cell and the loop voltage of the energized main circuit; It should be noted that the loop voltage is the real-time voltage data of the energized main circuit, that is, the voltage of the series loop formed by the remaining normal cells (excluding the abnormal cell). This data is acquired in real time by a voltage sampling chip and serves as the benchmark for comparison with the voltage of the cooled cell. The stability of this data directly affects the accuracy of the voltage difference calculation, providing a reliable reference for determining the appropriate timing for subsequent connection.

[0084] Furthermore, the target voltage difference is the absolute value of the voltage of the cooled battery cell and the circuit voltage, calculated in real time by the BMS main control module, which can intuitively reflect the degree of voltage matching between the two. The magnitude of this difference determines whether the battery cell meets the conditions for safe connection; the smaller the difference, the lower the risk of current surge during connection.

[0085] Understandably, the BMS main control module synchronously acquires the voltage of the cooling battery cell and the loop voltage of the energized main circuit through the voltage sampling chip, calculates the absolute value of the two in real time, and obtains the target voltage difference, which provides the core basis for subsequent judgment on whether to close the solid-state relay.

[0086] Step S43: When the target voltage difference is less than or equal to a preset voltage difference threshold, control the solid-state relay in the high-voltage switch assembly corresponding to the cooled battery cell to close, so as to restore the abnormal battery cell and obtain the restored battery cell.

[0087] It should be noted that the preset voltage difference threshold is a standard for determining whether a battery cell can be safely connected. It is set to 10 millivolts. When the target voltage difference is less than or equal to this threshold, it indicates that the voltage of the cooled battery cell is basically matched with the circuit voltage, and no excessive current surge will occur during connection. This threshold is set based on the current surge safety standard when connecting the battery cell, ensuring electrical safety during the connection process.

[0088] Additionally, solid-state relay closure refers to the solid-state relay in the high-voltage switchgear responding to control commands to physically connect the cooled battery cell to the energized main circuit. This action must be performed after voltage matching meets the requirements and is a critical operation for connecting the battery cell to the main circuit. Solid-state relays have fast response characteristics and can close promptly after the voltage meets the requirements, ensuring a smooth connection process.

[0089] Furthermore, a "recovered cell" refers to a cooled cell that has been pre-charged and voltage-regulated, achieved voltage matching standards, and successfully connected to the main power circuit after the solid-state relay is closed. Its electrical parameters are consistent with those of a normal cell, enabling it to participate normally in the charge-discharge cycle of the battery pack. In this embodiment, cell number 36 of the ternary lithium battery pack and the faulty cell of the lithium iron phosphate battery pack both become recovered cells through this process.

[0090] Understandably, by monitoring the target voltage difference in real time, when the difference is less than or equal to a preset voltage difference threshold of 10 millivolts, the BMS main control module sends a control command to close the solid-state relay in the high-voltage switch assembly corresponding to the cooled battery cell, thus completing the recovery of the abnormal battery cell and obtaining a recovered battery cell. (Refer to...) Figure 5 , Figure 5 This is a schematic diagram of the cell recovery process in the first embodiment of the cell isolation and recovery method for the battery pack of this application.

[0091] like Figure 5 As shown, starting from receiving the recoverable command, the pre-charge voltage regulation circuit is first activated, monitoring the voltage difference ΔU, which equals U1 minus U2. If ΔU is greater than 10 millivolts, monitoring continues; if ΔU is less than or equal to 10 millivolts, the solid-state relay is closed, disconnecting the backup branch. Subsequently, the dynamic power compensation algorithm is activated, monitoring the battery pack voltage change ΔUtotal. If ΔUtotal is less than or equal to 1%, the output current is increased; if ΔUtotal is greater than 1%, normal control is maintained. After the power stabilizes, the cell connection is completed. The entire process ensures that abnormal cells can be safely and accurately reconnected to the main circuit. Pre-charge voltage regulation and power compensation ensure a smooth transition between the cell voltage and the main circuit voltage, avoiding current surges and improving the safety and reliability of cell recovery.

[0092] This embodiment provides a method for cell isolation and recovery of a battery pack. By using technical means such as battery management system operation status detection, abnormal circuit isolation, dynamic heat dissipation adjustment, health assessment, and precise access control, it solves the technical problem of how to quickly isolate and safely restore the power battery of a new energy vehicle when the cell is abnormal. It achieves the beneficial effects of improving battery pack safety, extending battery life, reducing maintenance costs, and improving vehicle driving continuity.

[0093] Based on the first embodiment of this application, in the second embodiment of this application, the content that is the same as or similar to that in Embodiment 1 above can be referred to the above description, and will not be repeated hereafter. Based on this, please refer to... Figure 6 The cell isolation and recovery method of the battery pack includes steps S31 to S32 in step S30: Step S31: Determine the target isolation scenario based on the operating status of the battery management system; It should be noted that the target isolation scenarios are divided into two categories based on the operating status of the battery management system: active isolation scenarios and passive isolation scenarios. Different scenarios correspond to different health assessment initiation conditions and procedures, which are prerequisites for accurate health assessment execution. Active isolation scenarios correspond to situations where the battery management system is operating normally, while passive isolation scenarios correspond to situations where the battery management system is malfunctioning. This division ensures the compatibility between health assessment and isolation methods.

[0094] Understandably, by detecting the operating status of the battery management system, if the operating status is normal, the target isolation scenario is determined to be an active isolation scenario; if the operating status is malfunctioning, the target isolation scenario is determined to be a passive isolation scenario, providing a basis for subsequent targeted health assessments.

[0095] Step S32: Perform a health assessment based on the target isolation scenario and the cooling battery cell to obtain the health assessment result.

[0096] It should be noted that the health assessment is a process that combines the characteristics of the target isolation scenario with the real-time status data of the cooled battery cell, and uses a health assessment algorithm to continuously verify multiple parameters. The purpose is to accurately determine whether the cooled battery cell meets the conditions for safe restoration of its connection to the main circuit. This assessment process strictly follows the start-up timing and judgment criteria corresponding to the target isolation scenario to ensure the accuracy and reliability of the assessment results.

[0097] In addition, the health assessment results are the judgment conclusions generated after the health assessment, including the recoverable instruction and the continuous isolation instruction. The recoverable instruction indicates that the cooled battery cell meets all health threshold requirements, while the continuous isolation instruction indicates that the battery cell does not yet meet the conditions for recovery and needs to be kept in isolation for continued monitoring.

[0098] Understandably, if the target isolation scenario is an active isolation scenario, the temperature, voltage, internal resistance, and capacity decay rate of the cooling battery cell are continuously monitored for 5 minutes. If all parameters meet the corresponding health threshold, a recoverable command is generated; otherwise, a continuous isolation command is generated. If the target isolation scenario is a passive isolation scenario, after the temperature of the self-resetting fuse drops below 40 degrees Celsius and a reset signal is sent, the parameters of the cooling battery cell are checked according to the same health threshold. If the threshold is met, a recoverable command is generated; otherwise, a continuous isolation command is generated.

[0099] In one feasible implementation, when the battery management system is in normal operation, the isolation scenario is determined to be an active isolation scenario; When the battery management system is in a state of recovery after failure, the isolation scenario is determined to be a passive isolation scenario. When the target isolation scenario is the passive isolation scenario, detect whether a reset signal from the passive control component is received; Upon receiving the reset signal or when the target isolation scenario is the active isolation scenario, a health assessment is performed based on the cooled battery cell to obtain the health assessment result.

[0100] It should be noted that the battery management system is in normal operation, which means that the battery management system can receive data uploaded by the multi-parameter acquisition module, execute the multi-parameter fusion early warning algorithm, dynamic power compensation algorithm and health assessment algorithm normally, and send various control commands to the cell-level control execution module and realize real-time signal interaction.

[0101] Another active isolation scenario is the isolation scenario corresponding to the normal operation state of the battery management system. In this scenario, the battery management system sends a command to disconnect the solid-state relay and a command to turn on the dual redundant backup branch to the high-voltage switch assembly of the abnormal cell to achieve isolation between the abnormal cell and the main circuit, while maintaining the continuous conduction of the energized main circuit.

[0102] Furthermore, the battery management system's post-failure recovery status refers to a state where the battery management system previously experienced a malfunction that prevented it from executing active control commands, but subsequently resolved the fault and restored its normal operating capabilities. In this state, the battery management system can re-receive data, execute algorithms, and send commands, providing support for subsequent health assessments and cell recovery.

[0103] Another passive isolation scenario is the isolation scenario corresponding to the recovery of the battery management system after failure. In this scenario, the abnormal cell was isolated by the overcurrent heating of the self-resetting fuse of the passive control component, and the current maintained the circuit conduction through the metal conductor.

[0104] Furthermore, the reset signal is a signal sent by the passive control component to the battery management system after the temperature of the self-resetting fuse in the passive control component drops below 40 degrees Celsius and automatically returns to a low-resistance state. This signal is used to inform the battery management system that the passive isolation state has been released and the cell meets the prerequisites for health assessment.

[0105] Additionally, the passive control component is part of the cell-level control execution module. It integrates a self-resetting fuse and a metal current-conducting plate. It does not rely on the active commands of the battery management system. When an abnormal cell causes a sudden increase in circuit current, it can isolate the abnormal cell through the sudden change in the resistance value of the self-resetting fuse. At the same time, it can maintain conduction by absorbing the circuit current through the metal current-conducting plate. It is the core protection component when the battery management system fails.

[0106] Furthermore, the cooled battery cell is an abnormal battery cell whose temperature has been reduced to a preset safe range after focusing on heat dissipation control. Its temperature status has been controlled through dynamically adjusted heat dissipation methods, avoiding the risk of thermal runaway and providing the basic conditions for conducting health assessments.

[0107] In addition, health assessment is a process of comprehensively verifying multiple status data of the cooled battery cell, such as real-time temperature, voltage, internal resistance, and capacity decay rate, through a health assessment algorithm integrated into the battery management system. The purpose is to determine whether the cooled battery cell meets the conditions for safe connection to the main power circuit.

[0108] Furthermore, the health assessment results are the judgment conclusions generated after the health assessment process is completed, including two types: recoverable instructions and continuous isolation instructions. The recoverable instructions indicate that all parameters of the cooled battery cell meet the access requirements, while the continuous isolation instructions indicate that the battery cell does not yet meet the conditions for recovery and needs to be kept in isolation for continued monitoring.

[0109] Understandably, when the battery management system is detected to be operating normally, the isolation scenario is directly determined to be an active isolation scenario; when the battery management system is detected to be recovering from a failure, the isolation scenario is determined to be a passive isolation scenario. In a passive isolation scenario, the system continuously monitors whether a reset signal from the passive control component is received. If this reset signal is received, or if the isolation scenario itself is an active isolation scenario, a health assessment is performed based on real-time data such as the temperature, voltage, internal resistance, and capacity decay rate of the cooled battery cell, using a health assessment algorithm to obtain the final health assessment result.

[0110] In one feasible implementation, step S32 may include steps S321 to S322: Step S321: When the target isolation scenario is an active isolation scenario, acquire the monitoring time period, preset temperature range, preset voltage range, internal resistance deviation threshold, and capacity decay rate threshold. It should be noted that the active isolation scenario corresponds to the isolation scenario where the battery management system is operating normally. In this scenario, the abnormal cell is isolated by sending a command to disconnect the solid-state relay and a command to turn on the dual redundant backup branch. Subsequent health assessments need to be carried out based on continuous and stable parameter monitoring.

[0111] In addition, the monitoring period is a fixed duration for continuously collecting data on the status of the cooling battery cells, set to 5 minutes. This duration ensures that the stable status of the battery cell parameters is captured, avoiding misjudgments in health assessment due to instantaneous data fluctuations, and providing a time dimension guarantee for accurately determining whether the battery cell has the conditions for recovery.

[0112] Furthermore, the preset temperature range is the temperature range for the safe recovery of the battery cell, set to 25 degrees Celsius to 45 degrees Celsius. The lower limit of 25 degrees Celsius corresponds to the low temperature criticality for normal operation of the battery cell, and the upper limit of 45 degrees Celsius corresponds to the high temperature criticality for no thermal risk of the battery cell. If the temperature is stable within this range, it means that the thermal state of the battery cell has been restored to safety and there is no risk of thermal runaway.

[0113] Additionally, the preset voltage range is the standard voltage for the battery cell to reconnect to the main circuit. It varies depending on the type of battery cell. The preset voltage range for ternary lithium batteries is 3.6 volts to 3.8 volts, and the preset voltage range for lithium iron phosphate batteries is 3.2 volts to 3.4 volts. A voltage within this range indicates that the internal chemical properties of the battery cell are stable, the charging and discharging state is normal, and it can adapt to the voltage environment of the main circuit.

[0114] Furthermore, the internal resistance deviation threshold is the standard for judging whether the internal resistance of the battery cell has returned to normal. It is set to ±10% of the historical baseline. Internal resistance is a core parameter reflecting the internal conductivity of the battery cell. If the deviation is within this range, it indicates that there are no residual problems such as damage or short circuits in the internal structure of the battery cell, and the conductivity has returned to stability.

[0115] In addition, the capacity decay rate threshold is the upper limit of the capacity loss that the battery cell can recover. It is set to no more than 2% per 100 cycles. The capacity decay rate reflects the battery cell's ability to be used for a long time. Below this threshold, it means that the battery cell's capacity loss is slight and can still meet the vehicle's power output requirements, thus having the value of continuous use.

[0116] Understandably, when the target isolation scenario is an active isolation scenario, the corresponding monitoring time period, preset temperature range, preset voltage range, internal resistance deviation threshold, and capacity decay rate threshold are obtained to construct a complete health assessment and judgment system, providing clear standards for subsequent continuous monitoring and condition verification.

[0117] Step S322: During the monitoring period, if the real-time temperature of the cooled battery cell is within the preset temperature range, the voltage of the cooled battery cell is within the preset voltage range, the deviation of the internal resistance data of the cooled battery cell from the historical baseline does not exceed the internal resistance deviation threshold, and the capacity decay rate data of the cooled battery cell is less than the capacity decay rate threshold, a health assessment result that allows recovery is generated.

[0118] Understandably, within the set monitoring period, real-time temperature, voltage, internal resistance data, and capacity decay rate data of the cooled battery cells are continuously collected and compared with preset temperature ranges, preset voltage ranges, internal resistance deviation thresholds, and capacity decay rate thresholds, respectively. In this embodiment, the cooled battery cells of the ternary lithium battery pack are continuously monitored for 5 minutes. The real-time temperature of 42 degrees Celsius is within the preset temperature range of 25 to 45 degrees Celsius; the voltage of 3.7 volts is within the preset voltage range of 3.6 to 3.8 volts; the deviation of the internal resistance data from the historical baseline is 8%, which does not exceed the internal resistance deviation threshold of ±10%; and the capacity decay rate data is 1.2% per 100 cycles, which is less than the capacity decay rate threshold of 2% per 100 cycles. All conditions are met, therefore a health assessment result allowing recovery is generated.

[0119] This embodiment provides a cell isolation and recovery method for a battery pack. By determining the target isolation scenario based on the operating status of the battery management system and executing the corresponding health assessment process under different scenarios, it solves the technical problem of how to accurately assess the health status of cells and decide whether to restore them when the battery management system may fail. This achieves the beneficial effects of improving the safety, reliability and lifespan of power batteries for new energy vehicles, while also optimizing the adaptability and robustness of the battery management system under different operating conditions.

[0120] For example, to help understand the implementation process of the cell isolation and recovery method for the battery pack obtained by combining this embodiment with the above embodiment one, please refer to... Figure 7 , Figure 7 A simplified flowchart of a cell isolation and recovery method for a battery pack is provided, specifically: Starting from the initial node, the system first enters Phase 1, anomaly identification and control. In this phase, a dual check is performed to determine if an anomaly has been triggered. If not, it returns to anomaly identification and control for continued monitoring; if triggered, it enters Phase 2, rapid isolation control. In rapid isolation control, the system checks the BMS's functionality. If the BMS is normal, active isolation is executed, i.e., disconnecting the relay and connecting the backup circuit. If the BMS is abnormal, passive isolation is executed, i.e., the self-resetting fuse activates. Next, Phase 3 focuses on heat dissipation control. In this phase, the heat dissipation power is dynamically adjusted based on the cell temperature to improve cooling efficiency. Phase 4 is health assessment control, which continuously monitors the real-time data of the abnormal cell and executes a health assessment algorithm. If the recovery conditions are met, a recoverable command is generated; otherwise, isolation is maintained and monitoring continues. Phase 5 is precise access control, which uses pre-charge voltage regulation buffering to avoid current surges and ensure the cell's safe access to the main circuit. Finally, the control process ends after the cell is safely accessed. Through the control logic of different phases, the system achieves full-process control of anomaly identification, rapid isolation, heat dissipation, health assessment, and precise access for new energy vehicle power battery cells, ensuring the safe operation of the battery pack and the effective recovery of the cells.

[0121] It should be noted that the above examples are only for understanding this application and do not constitute a limitation on the cell isolation and recovery method of the battery pack of this application. Any simple modifications based on this technical concept are within the protection scope of this application.

[0122] This application also provides a cell isolation and recovery device for a battery pack; please refer to [reference needed]. Figure 8 The cell isolation and recovery device for the battery pack includes: The anomaly detection module 10 is used to determine the operating status of the battery management system when there is a battery cell anomaly command, and to isolate the abnormal circuit according to the operating status of the battery management system to obtain the abnormal battery cell status and the power-on main circuit. The cell cooling module 20 is used to determine the target valve opening degree according to the abnormal cell state, and control the opening degree of the heat dissipation control component according to the target valve opening degree, so as to cool down the abnormal cell and obtain a cooled cell. The health assessment module 30 is used to perform a health assessment based on the operating status of the cooled battery cell and the battery management system, and obtain a health assessment result. The cell recovery module 40 is used to recover abnormal cells from the cooled cells according to the health assessment results, obtain recovered cells, and connect the recovered cells to the power-on main circuit to complete the cell isolation and recovery of the battery pack.

[0123] The battery pack cell isolation and recovery device provided in this application, employing the battery pack cell isolation and recovery method described in the above embodiments, can solve the technical problem of how to achieve more timely, accurate, and safe handling without affecting the normal power supply of the vehicle when a cell malfunctions. Compared with the prior art, the beneficial effects of the battery pack cell isolation and recovery device provided in this application are the same as those of the battery pack cell isolation and recovery method provided in the above embodiments, and other technical features in the battery pack cell isolation and recovery device are the same as those disclosed in the methods of the above embodiments, and will not be repeated here.

[0124] This application provides a cell isolation and recovery device for a battery pack. The cell isolation and recovery device for a battery pack includes: at least one processor; and a memory communicatively connected to 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 cell isolation and recovery method for the battery pack in the above embodiment 1.

[0125] The following is for reference. Figure 9 This document illustrates a structural schematic diagram of a cell isolation and recovery device suitable for implementing the battery pack embodiments of this application. The cell isolation and recovery device for the battery pack in the embodiments of this application may include, but is not limited to, mobile terminals such as mobile phones, laptops, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Description), PMPs (Portable Media Players), in-vehicle terminals (e.g., in-vehicle navigation terminals), and fixed terminals such as digital TVs and desktop computers. Figure 9 The battery pack cell isolation and recovery device shown is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of this application.

[0126] like Figure 9As shown, the cell isolation and recovery device of the battery pack may include a processing device 1001 (e.g., a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in ROM (Read Only Memory) 1002 or a program loaded from storage device 1003 into RAM (Random Access Memory) 1004. RAM 1004 also stores various programs and data required for the operation of the cell isolation and recovery device of the battery pack. The processing device 1001, ROM 1002, and RAM 1004 are interconnected via bus 1005. Input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems can be connected to I / O interface 1006: input devices 1007 including, for example, touchscreens, touchpads, keyboards, mice, image sensors, microphones, accelerometers, gyroscopes, etc.; output devices 1008 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices 1003 including, for example, magnetic tapes, hard disks, etc.; and communication devices 1009. Communication device 1009 allows the battery pack's cell isolation and recovery equipment to communicate wirelessly or wiredly with other devices to exchange data. Although the figure shows a battery pack's cell isolation and recovery equipment with various systems, it should be understood that implementing or having all the systems shown is not required. More or fewer systems can be implemented alternatively.

[0127] Specifically, according to the embodiments disclosed in this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments disclosed in this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device, or installed from storage device 1003, or installed from ROM 1002. When the computer program is executed by processing device 1001, it performs the functions defined in the methods of the embodiments disclosed in this application.

[0128] The battery pack cell isolation and recovery device provided in this application, employing the battery pack cell isolation and recovery method described in the above embodiments, can solve the technical problem of how to achieve more timely, accurate, and safe handling without affecting the normal power supply of the vehicle when a cell malfunctions. Compared with the prior art, the beneficial effects of the battery pack cell isolation and recovery device provided in this application are the same as those of the battery pack cell isolation and recovery method provided in the above embodiments, and other technical features in the battery pack cell isolation and recovery device are the same as those disclosed in the previous embodiment method, and will not be repeated here.

[0129] It should be understood that the various parts disclosed in this application can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0130] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0131] This application provides a computer-readable storage medium having computer-readable program instructions (i.e., a computer program) stored thereon, which are used to execute the cell isolation and recovery method of the battery pack in the above embodiments.

[0132] The computer-readable storage medium provided in this application may be, for example, a USB flash drive, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: electrical connections having one or more wires, portable computer disks, hard disks, RAM (Random Access Memory), ROM (Read Only Memory), Erasable Programmable Read Only Memory (EPROM), optical fiber, CD-ROM (CD-Read Only Memory), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, system, or device. The program code contained on the computer-readable storage medium may be transmitted using any suitable medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination thereof.

[0133] The aforementioned computer-readable storage medium may be included in the cell isolation and recovery device of the battery pack; or it may exist independently and not assembled into the cell isolation and recovery device of the battery pack.

[0134] The aforementioned computer-readable storage medium carries one or more programs. When these programs are executed by the battery pack's cell isolation and recovery device, the battery pack's cell isolation and recovery device: upon the presence of a cell abnormality instruction, determines the operating state of the battery management system and isolates abnormal circuits based on the operating state of the battery management system to obtain the abnormal cell state and the energized main circuit; determines the target valve opening based on the abnormal cell state and controls the opening of the heat dissipation control component based on the target valve opening to cool the abnormal cell, obtaining a cooled cell; performs a health assessment based on the cooled cell and the operating state of the battery management system to obtain a health assessment result; and restores the cooled cell based on the health assessment result to obtain a restored cell, and connects the restored cell to the energized main circuit to complete the battery pack's cell isolation and recovery.

[0135] Computer program code for performing the operations of this application can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, as well as conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone 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 remote computers, the remote computer can be connected to the user's computer via any type of network—including LAN (Local Area Network) or WAN (Wide Area Network)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0136] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0137] The modules described in the embodiments of this application can be implemented in software or hardware. The names of the modules do not necessarily limit the functionality of the unit itself.

[0138] The readable storage medium provided in this application is a computer-readable storage medium that stores computer-readable program instructions (i.e., a computer program) for executing the cell isolation and recovery method of the battery pack described above. This solves the technical problem of how to achieve more timely, accurate, and safe handling of battery cell malfunctions without affecting the vehicle's normal power supply. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in this application are the same as those of the cell isolation and recovery method of the battery pack provided in the above embodiments, and will not be repeated here.

[0139] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the battery pack cell isolation and recovery method described above.

[0140] The computer program product provided in this application can solve the technical problem of how to achieve more timely, accurate, and safe handling without affecting the normal power supply of the vehicle when a battery cell malfunctions. Compared with the prior art, the beneficial effects of the computer program product provided in this application are the same as the beneficial effects of the battery cell isolation and recovery method of the battery pack provided in the above embodiments, and will not be repeated here.

[0141] The above description is only a part of the embodiments of this application and does not limit the patent scope of this application. All equivalent structural transformations made under the technical concept of this application and using the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included in the patent protection scope of this application.

Claims

1. A method for cell isolation and recovery in a battery pack, characterized in that, The method includes: When a cell malfunction command is received, the operating status of the battery management system is determined, and the abnormal circuit is isolated according to the operating status of the battery management system to obtain the abnormal cell status and the power-on main circuit. The target valve opening is determined based on the abnormal cell state, and the opening of the heat dissipation control component is controlled based on the target valve opening to cool down the abnormal cell and obtain a cooled cell. A health assessment is performed based on the operating status of the cooled battery cell and the battery management system to obtain the health assessment results. Based on the health assessment results, the abnormal battery cell is restored to a recovered battery cell, and the recovered battery cell is connected to the main power circuit to complete the battery pack's cell isolation and restoration.

2. The method as described in claim 1, characterized in that, The step of performing a health assessment based on the operating status of the cooled battery cell and the battery management system to obtain the health assessment result includes: The target isolation scenario is determined based on the operating status of the battery management system. A health assessment is performed based on the target isolation scenario and the cooling battery cell to obtain the health assessment results.

3. The method as described in claim 2, characterized in that, The step of conducting a health assessment in the target isolation scenario and the cooled battery cell to obtain the health assessment results further includes: When the target isolation scenario is an active isolation scenario, the monitoring time period, preset temperature range, preset voltage range, internal resistance deviation threshold, and capacity decay rate threshold are obtained. During the monitoring period, if the real-time temperature of the cooled battery cell is within the preset temperature range, the voltage of the cooled battery cell is within the preset voltage range, the deviation of the internal resistance data of the cooled battery cell from the historical baseline does not exceed the internal resistance deviation threshold, and the capacity decay rate data of the cooled battery cell is less than the capacity decay rate threshold, a health assessment result that allows recovery is generated.

4. The method as described in claim 1, characterized in that, Based on the health assessment results, the abnormal battery cell is restored using the following steps to obtain a restored battery cell: When the health assessment result indicates that recovery is permissible, a pre-charge voltage regulation command is sent to the high-voltage switch assembly of the cooled battery cell, so that the high-voltage switch assembly activates the pre-charge voltage regulation circuit according to the pre-charge voltage regulation command to regulate the voltage of the cooled battery cell and provides feedback on the voltage of the cooled battery cell. Determine the target voltage difference between the voltage of the cooled battery cell and the loop voltage of the energized main circuit; When the target voltage difference is less than or equal to a preset voltage difference threshold, the solid-state relay in the high-voltage switch assembly corresponding to the cooled battery cell is closed to restore the abnormal battery cell and obtain a restored battery cell.

5. The method as described in claim 1, characterized in that, The steps of determining the target valve opening based on the abnormal cell state and controlling the opening of the heat dissipation control component based on the target valve opening to cool down the abnormal cell and obtain a cooled cell include: The abnormal battery cell is obtained with its cell temperature, first preset temperature threshold, second preset temperature threshold, first valve opening, second valve opening, first coolant flow rate, and second coolant flow rate, wherein the first preset temperature threshold is less than the second preset temperature threshold, the first valve opening is less than the second valve opening, and the first coolant flow rate is less than the second coolant flow rate. When the cell temperature is greater than the first preset temperature threshold and less than the second preset temperature threshold, the target valve opening is determined to be the first valve opening, and the opening of the heat dissipation control component is controlled according to the target valve opening. The heat dissipation control component is controlled to operate at the first coolant flow rate to cool down the abnormal cell and obtain a cooled cell. When the cell temperature is greater than or equal to the second preset temperature threshold, the target valve opening is determined to be the second valve opening, and the opening of the heat dissipation control component is controlled according to the target valve opening. The heat dissipation control component is controlled to operate at the second coolant flow rate to cool down the abnormal cell and obtain a cooled cell.

6. The method as described in claim 1, characterized in that, The steps for isolating abnormal circuits based on the operating status of the battery management system to obtain the abnormal cell status and the power-on main circuit include: When the battery management system is determined to be operating normally, a first control command and a second control command are sent to the high-voltage switch assembly of the abnormal cell, so that the high-voltage switch assembly controls the solid-state relay to disconnect according to the first control command and controls the dual redundant backup branch to conduct according to the second control command, so as to isolate the abnormal circuit and obtain the abnormal cell status and the main power-on circuit. When the battery management system is determined to be in a failed state, the passive control component corresponding to the target cell is controlled to perform passive abnormal circuit isolation, thereby obtaining the abnormal cell state and the power-on main circuit.

7. The method as described in claim 1, characterized in that, Before the steps of determining the battery management system's operating state upon receiving a cell malfunction command, and isolating the malfunctioning circuit based on the battery management system's operating state to obtain the malfunctioning cell state and the power-on main circuit, the method further includes: Acquire cell temperature data, temperature change rate data, cell voltage data, cell internal resistance data, circuit current data, abnormal temperature threshold, second abnormal temperature threshold, temperature change rate threshold, cell voltage change threshold, cell internal resistance change threshold, and instantaneous short-circuit current threshold. A cell abnormality command is generated when any one of the following conditions is met: the cell temperature data exceeds the abnormal temperature threshold; the temperature change rate data exceeds the temperature change rate threshold; the cell voltage data change exceeds the cell voltage change threshold; the cell internal resistance data change exceeds the cell internal resistance change threshold; or the circuit current data exceeds the instantaneous short-circuit current threshold.

8. A cell isolation and recovery device for a battery pack, characterized in that, The device includes: An anomaly detection module is used to determine the operating status of the battery management system when an abnormal cell command is present, and to isolate the abnormal circuit based on the operating status of the battery management system to obtain the abnormal cell status and the power-on main circuit. A cell cooling module is used to determine the target valve opening degree based on the abnormal cell state, and control the opening degree of the heat dissipation control component based on the target valve opening degree, so as to cool down the abnormal cell and obtain a cooled cell. The health assessment module is used to perform a health assessment based on the operating status of the cooling battery cell and the battery management system, and obtain the health assessment result. The cell recovery module is used to recover abnormal cells from the cooled cells based on the health assessment results, obtain recovered cells, and connect the recovered cells to the power-on main circuit to complete the cell isolation and recovery of the battery pack.

9. A cell isolation and recovery device for a battery pack, characterized in that, The device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the cell isolation and recovery method for the battery pack as described in any one of claims 1 to 7.

10. A storage medium, characterized in that, The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, it implements the steps of the cell isolation and recovery method of the battery pack as described in any one of claims 1 to 7.

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