A battery pack thermal runaway protection method and system

Abstract

The application relates to the technical field of battery pack energy storage control, and discloses a battery pack thermal runaway protection method and system, wherein the method comprises the following steps: collecting real-time parameters of battery cells; generating a control instruction to drive a cluster-level electromagnetic valve to spray; performing multi-parameter trend consistency verification; determining whether to trigger full-cluster spraying after a signal is received by a fire-fighting host; and completing subsequent closed-loop control. Compared with the prior art which is based on a single temperature or voltage threshold for static judgment, especially in complex working conditions where the thermal runaway of the battery cell develops in a nonlinear mutation manner, local sensing point is abnormal or communication is delayed, the prior art cannot realize the linkage response processing of the real thermal runaway event. Since the layered trend fusion judgment mechanism and the fire extinguishing temperature trend closed-loop verification mechanism are constructed, the complete closed-loop process from early thermal runaway discrimination to multi-stage linkage spraying to fire extinguishing effectiveness feedback is realized, and the thermal safety protection capability under extreme working conditions is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of battery pack energy storage control, and particularly to a method and system for thermal runaway protection of battery packs. Background Art

[0002] Currently, existing energy storage systems usually set thermal runaway trigger logic in the battery management system (BMS) and suppress it by dry contact linkage with a fire sprinkler device. However, the existing technology still has the following significant deficiencies: On the one hand, the thermal runaway trigger criterion generally adopts a single-threshold judgment logic. For example, when the temperature is greater than 80°C or the voltage is lower than 2V, it is regarded as abnormal. However, such static criteria cannot fully reflect the dynamic trend of thermal runaway evolution and are easily interfered by short-term fluctuations, resulting in false judgments or missed judgments. For example, in high ambient temperature or slow average temperature rise scenarios, the early characteristics of local thermal mutations may be masked; while instantaneous high-temperature perturbations may also be misidentified as runaway signals. On the other hand, the linkage logic between the BMS and the fire protection system often lacks real-time and credibility verification. In the existing solutions, the BMS directly outputs a dry contact signal only after identifying "suspected thermal runaway", and the fire protection host has no way to judge the authenticity of the reported data, nor does it have a cross-node data verification or trend consistency judgment mechanism, which is prone to false spraying or missed spraying in case of communication anomalies, node failures or data drift. In an actual project, a false alarm in a certain cluster led to the activation of the entire station's fire protection, the release of all agents, resulting in economic losses and system shutdown; while the real thermal runaway of the battery cells was not sprayed in time due to delayed triggering, which instead led to the spread of the fire.

[0003] The existing technology cannot fully meet the safety requirements of high-precision identification, stable linkage control and closed-loop feedback of fire extinguishing effects for thermal runaway events under complex operating conditions, local abnormal evolution or linkage scenarios. Therefore, there is an urgent need for a battery thermal runaway protection method with dynamic multi-parameter trend judgment ability, linkage consistency verification mechanism and post-fire efficacy closed-loop feedback ability to improve the risk identification accuracy, linkage response stability and overall thermal safety protection level of energy storage systems under abnormal operating conditions. Summary of the Invention

[0004] Aiming at the above-mentioned technical deficiencies, the purpose of the present invention is to propose a method for thermal runaway protection of battery packs, aiming to solve the technical problem that in the existing technology, static judgments are mostly based on single temperature or voltage thresholds, especially in complex working conditions where the thermal runaway of battery cells develops non-linearly and mutates, there are local sensing point abnormalities or communication delays, and the linkage response processing of real thermal runaway events cannot be realized.

[0005] To solve the above technical problems, the present invention adopts the following technical solutions: The present invention provides a method for thermal runaway protection of battery packs,

[0006] The method for thermal runaway protection of battery packs includes:

[0007] Step S10: Collect the real-time operating parameters of cell i in the target battery pack at time t using a preset BCU unit, and determine whether the thermal runaway triggering condition is met based on the real-time operating parameters using a continuous interval joint state mechanism, and output the thermal runaway identification flag. ;

[0008] Step S20: Based on thermal runaway identification flags The corresponding electrical signal control command is generated, and the preset BCU unit outputs the electrical signal control command to the cluster-level solenoid valve control interface at the top of the battery cluster. At the same time, the real-time operating parameters and thermal runaway identification flag are also transmitted. Send to the superior BAU unit;

[0009] Step S30: Acquire cell thermal runaway feedback data. The upper-level BAU unit performs multi-parameter fitting trend consistency detection and cross-node validity verification based on real-time operating parameters and spraying status feedback data, and outputs dry contact closure signal. ;

[0010] Step S40: The fire alarm control panel receives the dry contact closure signal. When the dry contact closes the signal When =1, determine whether the global spraying fire suppression linkage condition is met. If it is met, issue a full-cluster spraying fire suppression command and output the global protection status flag F.

[0011] Step S50: When the global protection status flag F is 1, the target area temperature data is collected based on the preset infrared temperature measurement unit, the average temperature drop rate of the target area is calculated within the preset continuous time window, and the total temperature drop amplitude of the target area is obtained; the effectiveness of the fire extinguishing action is judged based on the average temperature drop rate and the total temperature drop amplitude of the target area, and the closed-loop control of the subsequent drive behavior is executed based on the judgment result.

[0012] Preferably, in step S10, a continuous interval joint state mechanism is used based on real-time operating parameters to determine whether the thermal runaway triggering condition is met, and a thermal runaway identification flag is output. The steps specifically include:

[0013] Real-time operating parameters include cell voltage Cell temperature and the rate of temperature rise per unit time Construct a continuous criterion set based on a sliding time window Δt, and determine whether the following three conditions are met simultaneously in the continuous criterion set:

[0014] Condition 1: Within the sliding time window Δt, the cell voltage The minimum value is less than 2V and there is no disconnection process;

[0015] Condition 2: Within the sliding time window Δt, the cell temperature The maximum value is greater than 80℃;

[0016] Condition 3: Within the sliding time window Δt, there exists at least one time point. At the point in time The temperature rise rate per unit time is greater than or equal to 1℃ / s and lasts for more than 3s;

[0017] If all three conditions above are met within the sliding time window Δt, then the thermal runaway identification flag will be output. Otherwise output .

[0018] Preferably, in step S20, the cluster-level solenoid valve control interface drives the nozzles within the cluster to start, enabling real-time operation of localized spraying for fire extinguishing.

[0019] Preferably, in step S30, the cell thermal runaway feedback data is acquired, and the upper-level BAU unit performs multi-parameter fitting trend consistency detection and cross-node validity verification based on real-time operating parameters and spraying status feedback data, and outputs dry contact closure signal. The steps specifically include:

[0020] Within the sliding time window Δt, the real-time operating parameters reported by the BCU unit are extracted, and the local operating parameters recorded by the BMS unit are collected.

[0021] Based on the comparison of the real-time operating parameters reported by the BCU unit and the local operating parameters recorded by the BMS unit, the consistency of the three fitting trends is evaluated, and the dry contact closure signal is output based on the comparison result of the consistency of the three fitting trends. .

[0022] Preferably, in step S30, the consistency of the three fitting trends is compared, and the dry contact closure signal is output based on the comparison result of the consistency of the three fitting trends. The specific steps include:

[0023] The least squares linear fitting method was used to fit the cell temperature data in the real-time operating parameters to obtain the first temperature trend line; the least squares linear fitting method was used to fit the cell temperature data in the local operating parameters to obtain the second temperature trend line.

[0024] The cell voltage data in the real-time operating parameters are fitted using a moving average combined with the first-order difference method to obtain the first voltage trend line; the cell voltage data in the local operating parameters are fitted using a moving average combined with the first-order difference method to obtain the second voltage trend line.

[0025] Compare the consistency of the following three fitting trends:

[0026] Condition 1: The fitting error in slope between the first temperature trend line and the second temperature trend line does not exceed the set first error threshold. ;

[0027] Condition 2: The fitting error in slope between the first voltage trend line and the second voltage trend line does not exceed the set second error threshold. ;

[0028] Condition 3: Obtain the spraying duration from the spraying status feedback data; the spraying duration must be greater than the set tolerance. ;

[0029] If all three conditions are met, the real-time operating parameters reported by the BCU unit are deemed reliable, and a dry contact closure signal is output. Conversely, output dry contact closure signal. 0.

[0030] Preferably, in step S40, the step of issuing a full-cluster spray fire extinguishing command and outputting the global protection status flag F if the condition is met specifically includes: if the condition is met, opening the cylinder solenoid valve connected to the fire control panel, starting the full-cluster spraying unit connected to the fire control panel to perform unified fire extinguishing operation, and simultaneously activating the data recorder, infrared thermal imaging and smoke monitoring unit connected to the fire control panel to perform linkage recording; and outputting the global protection status flag F.

[0031] Preferably, step S50, which involves determining the effectiveness of the fire extinguishing action based on the average temperature drop rate and the total temperature drop amplitude in the target area, and then performing closed-loop control of the subsequent driving behavior based on the determination result, specifically includes:

[0032] The effectiveness of fire extinguishing actions is determined based on the average temperature drop rate and the total temperature drop in the target area. The fire extinguishing action is deemed effective if both of the following conditions are met: Condition 1: The average temperature drop rate is less than or equal to 0.5℃ / s; Condition 2: The total temperature drop in the target area is greater than or equal to 15℃. Otherwise, the fire extinguishing action is deemed ineffective if either of the above conditions is not met.

[0033] When the fire extinguishing action is determined to be effective, the fire control panel disconnects the solenoid valve control circuit and records the current linkage event log.

[0034] When the fire extinguishing action is determined to be invalid, the fire control panel will continue the spraying action and send a linkage failure signal to the BMS unit.

[0035] The present invention also provides a battery pack thermal runaway protection system comprising:

[0036] The thermal runaway determination module is used to collect real-time operating parameters of cell i in the target battery pack at time t through a preset BCU unit, and to determine whether the thermal runaway triggering conditions are met based on the real-time operating parameters using a continuous interval joint state mechanism, and outputs a thermal runaway identification flag. ;

[0037] Linkage signal output module, used for thermal runaway identification flag bit The corresponding electrical signal control command is generated, and the preset BCU unit outputs the electrical signal control command to the cluster-level solenoid valve control interface at the top of the battery cluster. At the same time, the real-time operating parameters and thermal runaway identification flag are also transmitted. Send to the superior BAU unit;

[0038] The consistency verification module is used to acquire cell thermal runaway feedback data. The upper-level BAU unit performs multi-parameter fitting trend consistency detection and cross-node validity verification based on real-time operating parameters and spraying status feedback data, and outputs dry contact closure signal. ;

[0039] The global linkage judgment module is used by the fire alarm control panel to receive dry contact closure signals. When the dry contact closes the signal When =1, determine whether the global spraying fire suppression linkage condition is met. If it is met, issue a full-cluster spraying fire suppression command and output the global protection status flag F.

[0040] The fire extinguishing closed-loop control module is used to collect temperature data of the target area based on the preset infrared temperature measurement unit when the global protection status flag F is 1, calculate the average temperature drop rate of the target area within the preset continuous time window, and obtain the total temperature drop amplitude of the target area; perform fire extinguishing action effectiveness judgment based on the average temperature drop rate and the total temperature drop amplitude of the target area, and perform post-drive behavior closed-loop control based on the judgment result.

[0041] The present invention also provides a battery pack thermal runaway protection device, comprising: a memory, a processor, and a battery pack thermal runaway protection program stored in the memory and executable on the processor, wherein the battery pack thermal runaway protection program implements a battery pack thermal runaway protection method when executed by the processor.

[0042] The present invention also provides a computer program product, including a battery pack thermal runaway protection program, which, when executed by a processor, implements the battery pack thermal runaway protection method.

[0043] The beneficial effects of the present invention are as follows: By introducing a continuous time window criterion of voltage, temperature and temperature rise rate, the present invention effectively avoids the non-real thermal runaway triggering caused by false alarms or missed alarms due to a single threshold in the prior art, and significantly improves the accuracy and anti-interference ability of thermal runaway identification.

[0044] This invention realizes a multi-level response chain from front-end identification to end-point spraying and back-end verification through trend consistency verification of the upper-level BMS and fire extinguishing effect judgment mechanism of the fire control panel. Compared with traditional technical solutions that cannot judge the effectiveness of fire extinguishing, it significantly improves the safety protection efficiency and reliability of energy storage systems under complex working conditions. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This is a flowchart illustrating the first embodiment of a battery pack thermal runaway protection method according to the present invention.

[0047] Figure 2 This is a schematic diagram of the overall logic framework of a first embodiment of a battery pack thermal runaway protection method of the present invention.

[0048] Figure 3 This is a schematic diagram of a battery pack thermal runaway protection method according to the present invention. Detailed Implementation

[0049] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] Example 1: As Figure 1 The diagram shown is a flowchart of the first embodiment of the battery pack thermal runaway protection method of the present invention, which presents the first embodiment of the battery pack thermal runaway protection method of the present invention.

[0051] In the first embodiment, the battery pack thermal runaway protection method includes:

[0052] Step S10: Collect the real-time operating parameters of cell i in the target battery pack at time t using a preset BCU unit, and determine whether the thermal runaway triggering condition is met based on the real-time operating parameters using a continuous interval joint state mechanism, and output the thermal runaway identification flag. ;

[0053] It should be noted that the "continuous interval joint state mechanism" refers to the real-time monitoring of multiple operating parameters of the same battery cell within a preset continuous time range (e.g., 5 seconds or 10 seconds), and determining whether these parameters remain in an abnormal state throughout the entire time interval. Operating parameters include, but are not limited to: whether the cell voltage drops significantly, whether the temperature exceeds a set threshold, and whether the temperature change exhibits a rapid increase. Only when these conditions are simultaneously and continuously met within the time range will it be determined as a true thermal runaway state, and a corresponding identification flag will be output. This mechanism avoids over-reliance on "single-moment outliers," making the judgment more time-continuous and logically robust.

[0054] Understandably, by combining and continuously assessing multiple physical indicators over a certain period, the ability to identify early signs of thermal runaway is significantly improved. In the initial stage of thermal runaway, although the instantaneous values ​​of temperature or voltage may not yet reach the danger threshold, their changing trends already exhibit abnormal characteristics, such as a sustained and rapid rise in temperature and a continuous drop in voltage. This invention can issue early warning signals before thermal runaway fully erupts through continuous observation and combined logic, thereby gaining more reaction time for subsequent spray control and coordinated response.

[0055] It should be understood that traditional technical solutions typically rely on a single indicator (such as temperature exceeding 80°C) to trigger an alarm, lacking the ability to analyze the correlation and evolution process between parameters. This method is prone to misjudgment in the presence of sensor noise, data transients, or operating condition disturbances, especially when the cell temperature is close to but has not exceeded the threshold, it may not respond at all. The mechanism adopted in this invention, through "combined judgment and continuous verification," requires multiple abnormal features to exist simultaneously and remain for a certain period of time, thereby effectively reducing the false alarm rate and missed alarm rate, and improving the accuracy of judgment and response reliability for actual thermal runaway events.

[0056] Step S20: Based on thermal runaway identification flags The corresponding electrical signal control command is generated, and the preset BCU unit outputs the electrical signal control command to the cluster-level solenoid valve control interface at the top of the battery cluster. At the same time, the real-time operating parameters and thermal runaway identification flag are also transmitted. Send to the superior BAU unit;

[0057] It should be noted that the "electrical signal control command" refers to a hardware-level output signal automatically generated by the BAU after detecting that the target cell meets the thermal runaway conditions. This signal can be a relay closing signal, a level trigger signal, or an analog switch signal, used to directly drive the solenoid valve installed on top of the battery cluster to perform an opening action, thereby initiating local fire suppression. In addition, this step also includes reporting the current operating status data of the battery cell (such as temperature, voltage, timestamp) and the generated thermal runaway identification flag bit to the upper-level BAU unit through a communication link (such as CAN, RS485, or Ethernet) to achieve linkage response and fault data synchronization.

[0058] Understandably, this step not only enables rapid local response to thermal runaway events but also establishes an event reporting channel to the upper-level management unit, forming a two-tiered control structure of "edge identification + central linkage." This structure ensures that spraying actions are completed autonomously in the early stages of thermal runaway, while timely feedback of event information to the upper level. This provides basic data support for subsequent global spraying linkage, power distribution, energy isolation, and other actions, significantly improving the timeliness and coordination of the control response.

[0059] It should be understood that, unlike the traditional BMS's full control over thermal runaway judgment and fire suppression triggering mechanism, this invention forwards the judgment and primary control functions to the BAU, realizing an integrated closed loop of "judgment-control-response" at the cluster level. This design, while ensuring local response speed, avoids the delay and bottleneck problems in the multi-node signal convergence process of traditional centralized architectures, making it suitable for scenarios with a large number of clusters and high communication complexity in large-scale energy storage systems.

[0060] For example, in a certain experimental scenario, controlled heating simulation was performed on the sixth cell in a lithium battery cluster configured with 104S. Test data showed that after identifying the continuous temperature rise of the cell and meeting the thermal runaway criterion, a control command was generated within 0.5 seconds, directly driving the solenoid valve nozzle at the top of the cluster to perform local fire suppression. Simultaneously, the BCU uploaded abnormal parameters and identification status to the upper-level BAU unit via the CAN interface. The upper-level BAU unit recorded the response time and determined whether to trigger global spraying based on multiple subsequent upload results. Compared to the traditional method of relying on centralized judgment and control of spraying by the BMS, this local response mechanism shortened the average time in the first response stage by approximately 4 seconds, effectively suppressing local heat diffusion.

[0061] Step S30: Acquire cell thermal runaway feedback data. The upper-level BAU unit performs multi-parameter fitting trend consistency detection and cross-node validity verification based on real-time operating parameters and spraying status feedback data, and outputs dry contact closure signal. ;

[0062] It should be noted that "multi-parameter fitting trend consistency detection" refers to the process where, after receiving the thermal runaway identification flag and real-time parameters, the upper-level BAU unit retrieves its own recorded operating data for the corresponding cell or neighboring cells during the corresponding time period, including temperature, voltage, and temperature rise rate. It then performs fitting processing on the changing trends of these parameters to determine whether the two data points maintain consistency in trend direction, slope, or parameter change magnitude, thereby assessing the credibility of the reported event. Simultaneously, "cross-node validity verification" not only verifies the data of the cell itself but also compares it with the temperature and voltage changes of other adjacent or clustered cells to see if they exhibit similar anomalies. This enhances the spatial correlation of the judgment and reduces false triggering caused by single-point anomalies.

[0063] Understandably, by introducing trend fitting and inter-node comparison mechanisms, the authenticity of the event can be reconfirmed after receiving the spraying action trigger signal, thus avoiding false triggering caused by communication errors, data mutations, or local disturbances.

[0064] It should be understood that, compared to the existing technology where the BMS triggers the fire protection system after receiving an alarm signal, this invention significantly reduces the probability of single-point false alarms and sporadic triggering by introducing a parameter consistency judgment based on trend fitting and a spatial multi-point data comparison mechanism. Traditional methods lack analysis of data change processes and are prone to malfunctions due to sensor errors, clock skew, or short-term outliers; while in this invention, the BMS only outputs a dry contact signal when it determines that the BAU data is highly consistent with local or other node data at the trend level, thereby improving the reliability and redundancy tolerance of the fire response.

[0065] Step S40: The fire alarm control panel receives the dry contact closure signal. When the dry contact closes the signal When =1, determine whether the global spraying fire suppression linkage condition is met. If it is met, issue a full-cluster spraying fire suppression command and output the global protection status flag F.

[0066] It should be noted that the "global sprinkler extinguishing linkage condition" means that after the fire control panel receives the dry contact closure signal from the superior BMS, it does not directly trigger full-cluster spraying. Instead, it further confirms the current status, such as checking whether the spraying execution unit is in an operable state, whether the agent reserve meets the spraying conditions, and whether the power supply is normal, etc. Only when all the preconditions are met does the fire control panel determine that the linkage condition is established and immediately issue control commands to all cluster-level solenoid valves to implement the full-cluster spraying action. At the same time, the fire control panel updates the status flag to "global protection status", i.e., F=1, to notify subsequent modules to enter the fire extinguishing closed-loop monitoring stage.

[0067] Understandably, this step, acting as the hub of the coordinated control system, establishes a logical closed loop from BMS event judgment to the actual spraying command triggering, serving as a core bridging link in the "sensing-judgment-execution" chain of the entire thermal runaway response. By jointly judging the dry contact signal and its own execution status, it ensures that the fire sprinkler action will not be falsely triggered or fail due to misjudgment or equipment malfunction. Simultaneously, the output global protection status flag F provides a synchronous trigger signal for subsequent temperature trend judgments, enabling coordinated control between modules.

[0068] It should be understood that, compared to traditional fire sprinkler systems, which are typically triggered directly by the BMS, manual intervention, or fire control panel, lacking logical judgment and status synchronization regarding the execution state, the fire control panel in this invention, as an independent response unit, possesses proactive judgment capabilities and linkage coordination functions. Its secondary confirmation mechanism for sprinkler conditions effectively prevents erroneous execution of fire extinguishing actions under abnormal conditions or hardware defects. Simultaneously, through the output of the status flag F, a unified control chain is constructed from "sprinkler triggering" to "fire extinguishing feedback," which helps improve the accuracy and stability of the energy storage system's response to thermal runaway events in multi-cluster, highly complex environments.

[0069] Step S50: When the global protection status flag F is 1, the target area temperature data is collected based on the preset infrared temperature measurement unit, the average temperature drop rate of the target area is calculated within the preset continuous time window, and the total temperature drop amplitude of the target area is obtained; the effectiveness of the fire extinguishing action is judged based on the average temperature drop rate and the total temperature drop amplitude of the target area, and the closed-loop control of the subsequent drive behavior is executed based on the judgment result.

[0070] It should be noted that the "average temperature drop rate" in this step refers to the average rate of temperature decrease in the target area over a continuous period after spraying, reflecting the cooling trend after fire extinguishing; the "total temperature drop amplitude" refers to the maximum temperature drop during this period, reflecting whether the fire extinguishing achieved a significant thermal effect. Both indicators are obtained through real-time sampling data from infrared thermometers and statistically processed by the host computer. Based on this, a preset threshold is used to determine whether fire extinguishing was successful, and accordingly, a decision is made on whether to continue spraying and other subsequent response actions, forming a closed-loop control process for the fire extinguishing process.

[0071] Understandably, by introducing a dual judgment mechanism based on continuous temperature change trends and temperature drop amplitude, the effectiveness of fire suppression actions can be more accurately reflected. If the fire is successfully extinguished, spraying can automatically end and equipment resources can be released; if the fire is not sufficiently extinguished, and the temperature remains high or drops slowly, the spraying time can be extended, and the next round of response actions can begin to prevent the fire from reigniting or being missed. This strategy drives subsequent response logic through the perception results.

[0072] It should be understood that traditional fire-fighting linkage mechanisms are mostly based on fixed-time spraying, lacking the ability to assess fire extinguishing effectiveness in real time. If the fire is not completely extinguished, it often cannot be detected in time, which may lead to secondary combustion or waste of resources due to redundant spraying. In contrast, this invention introduces a fire extinguishing effectiveness identification mechanism that jointly judges the temperature change trend and the rate of temperature drop, realizing result-driven response strategy switching. It can not only autonomously determine whether spraying needs to continue, but also construct a result-oriented, end-to-end control closed loop, significantly improving safety and resource utilization efficiency.

[0073] For example, such as Figure 2 As shown, when a battery cell exhibits signs of thermal runaway due to overcharging or internal malfunction, multiple operating parameters of that cell will be monitored in real time. If the voltage of any single cell is below 2V and there is no data loss during the data acquisition process, and the temperature exceeds 80℃ with a temperature rise rate of more than 1℃ per second for more than 3 seconds, the cell is determined to have entered a thermal runaway state. At this time, the BCU (Battery Control Unit) immediately receives the judgment signal indicating that the above three conditions are met simultaneously and reports the event information to the BCU. Simultaneously, the following parallel actions are executed: First, the BCU directly opens the sprinkler ball valve at the top of the corresponding battery cluster and continuously outputs a 24V drive signal to implement a localized spray response; second, the BCU transmits the relevant status to the BAU, which then outputs a fire trigger signal to the fire control panel. Upon receiving the trigger signal, the fire control panel determines that the linkage conditions are met, opens the cylinder solenoid valve, releases the extinguishing agent, and initiates the full-cluster spray linkage action, completing the fire extinguishing activation process. The entire process has a short response time from thermal runaway identification to spray activation, and can quickly respond in the early stage of cell heating. It has a clear judgment mechanism and a highly integrated linkage control link, which verifies the adaptability and practical effect of the method of the present invention in multi-parameter and cross-module scenarios.

[0074] Example 2: Furthermore, the battery pack thermal runaway protection system provided by the present invention employs a battery pack thermal runaway protection method from the above embodiments, which can solve the technical problem of battery pack thermal runaway protection. Compared with the prior art, the beneficial effects of the battery pack thermal runaway protection system provided by the present invention are the same as those of the battery pack thermal runaway protection method provided in the above embodiments, and other technical features of the battery pack thermal runaway protection system are the same as those disclosed in the methods of the above embodiments, and will not be repeated here.

[0075] Example 3: This invention provides a battery pack thermal runaway protection device. Please refer to... Figure 3A battery pack thermal runaway protection device 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, which, when executed by the at least one processor, enable the at least one processor to perform a battery pack thermal runaway protection method as described in Embodiment 1 above. The battery pack thermal runaway protection device in this embodiment may include, but is not limited to, mobile terminals such as mobile phones, laptops, digital radio receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), and in-vehicle terminals (e.g., in-vehicle navigation terminals), as well as fixed terminals such as digital TVs and desktop computers. This battery pack thermal runaway protection device is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of this invention. A battery pack thermal runaway protection device may include a processing device 1001 (e.g., a central processing unit, a graphics processing unit, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory 1002 or a program loaded from a storage device 1003 into a random access memory 1004. Random access memory 1004 also stores various programs and data required for the operation of a battery pack thermal runaway protection device. Processing device 1001, read-only memory 1002, and random access memory 1004 are interconnected via bus 1005. 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 a battery pack thermal runaway protection device to communicate wirelessly or wiredly with other devices to exchange data. Although a battery pack thermal runaway protection device with various systems is shown in the figures, it should be understood that it is not required to implement or possess all the systems shown. More or fewer systems may be implemented alternatively.

[0076] Example 4: This invention also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the battery pack thermal runaway protection method described above. The computer program product provided by this invention can solve the technical problem of battery pack thermal runaway protection. Compared with the prior art, the beneficial effects of the computer program product provided by this invention are the same as those of the battery pack thermal runaway protection method provided in the above embodiments, and will not be repeated here.

[0077] In particular, according to the embodiments disclosed in this invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this invention 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 read-only memory 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 invention.

[0078] It should be understood that the various parts disclosed in this invention can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0079] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for thermal runaway protection of a battery pack, characterized in that, The methods include: Step S10: Collect the real-time operating parameters of the battery clusters in the target battery pack at time t for cell i using a preset BCU unit, and determine whether the thermal runaway triggering condition is met based on the real-time operating parameters using a continuous interval joint state mechanism, and output the thermal runaway identification flag. The system uses a continuous interval joint state mechanism based on real-time operating parameters to determine whether the thermal runaway triggering conditions are met, and outputs a thermal runaway identification flag. The steps specifically include: Real-time operating parameters include cell voltage Cell temperature and the rate of temperature rise per unit time Construct a continuous criterion set based on a sliding time window Δt, and determine whether the following three conditions are met simultaneously in the continuous criterion set: Condition 1: Within the sliding time window Δt, the cell voltage The minimum value is less than 2V and there is no disconnection process; Condition 2: Within the sliding time window Δt, the cell temperature The maximum value is greater than 80℃; Condition 3: Within the sliding time window Δt, there exists at least one time point. At the point in time The temperature rise rate per unit time is greater than or equal to 1℃ / s and lasts for more than 3s; If all three conditions above are met within the sliding time window Δt, then the thermal runaway identification flag will be output. Otherwise output ; Step S20: Based on thermal runaway identification flags The corresponding electrical signal control command is generated, and the preset BCU unit outputs the electrical signal control command to the cluster-level solenoid valve control interface at the top of the battery cluster. At the same time, the real-time operating parameters and thermal runaway identification flag are also transmitted. Send to the superior BAU unit; Step S30: Acquire cell thermal runaway feedback data. The upper-level BAU unit performs multi-parameter fitting trend consistency detection and cross-node validity verification based on real-time operating parameters and spraying status feedback data, and outputs dry contact closure signal. ; Among these processes, the upper-level BAU unit acquires thermal runaway feedback data from the battery cell, performs multi-parameter fitting trend consistency detection and cross-node validity verification based on real-time operating parameters and spraying status feedback data, and outputs dry contact closure signals. The steps specifically include: Within the sliding time window Δt, the real-time operating parameters reported by the BCU unit are extracted, and the local operating parameters recorded by the BMS unit are collected. Based on the comparison of the real-time operating parameters reported by the BCU unit and the local operating parameters recorded by the BMS unit, the consistency of the three fitting trends is evaluated, and the dry contact closure signal is output based on the comparison result of the consistency of the three fitting trends. ; Specifically, the consistency of the three fitting trends is compared, and the dry contact closure signal is output based on the comparison result of the consistency of the three fitting trends. The specific steps include: The least squares linear fitting method was used to fit the cell temperature data in the real-time operating parameters to obtain the first temperature trend line; the least squares linear fitting method was used to fit the cell temperature data in the local operating parameters to obtain the second temperature trend line. The cell voltage data in the real-time operating parameters are fitted using a moving average combined with the first-order difference method to obtain the first voltage trend line; the cell voltage data in the local operating parameters are fitted using a moving average combined with the first-order difference method to obtain the second voltage trend line. Compare the consistency of the following three fitting trends: Condition 1: The fitting error in slope between the first temperature trend line and the second temperature trend line does not exceed the set first error threshold. ; Condition 2: The fitting error in slope between the first voltage trend line and the second voltage trend line does not exceed the set second error threshold. ; Condition 3: Obtain the spraying duration from the spraying status feedback data; the spraying duration must be greater than the set tolerance. ; If all three conditions are met, the real-time operating parameters reported by the BCU unit are deemed reliable, and a dry contact closure signal is output. Conversely, output dry contact closure signal. 0; Step S40: The fire alarm control panel receives the dry contact closure signal. When the dry contact closes the signal When =1, determine whether the global spraying fire suppression linkage condition is met. If it is met, issue a full-cluster spraying fire suppression command and output the global protection status flag F. Step S50: When the global protection status flag F is 1, the target area temperature data is collected based on the preset infrared temperature measurement unit, the average temperature drop rate of the target area is calculated within the preset continuous time window, and the total temperature drop amplitude of the target area is obtained; the effectiveness of the fire extinguishing action is judged based on the average temperature drop rate and the total temperature drop amplitude of the target area, and the closed-loop control of the subsequent drive behavior is executed based on the judgment result.

2. The battery pack thermal runaway protection method as described in claim 1, characterized in that, In step S20, the cluster-level solenoid valve control interface drives the nozzles within the cluster to start, enabling real-time operation of localized spraying for fire extinguishing.

3. The battery pack thermal runaway protection method as described in claim 1, characterized in that, In step S40, if the global spraying fire extinguishing linkage condition is met and the global protection status flag F is output, the specific steps include: if the linkage condition is met, opening the cylinder solenoid valve connected to the fire control panel, starting the full-cluster spraying unit connected to the fire control panel for unified fire extinguishing operation, and simultaneously activating the data recorder, infrared thermal imaging and smoke monitoring unit connected to the fire control panel for linkage recording; and outputting the global protection status flag F.

4. A battery pack thermal runaway protection method as described in claim 1, characterized in that, Step S50 involves determining the effectiveness of the fire extinguishing action based on the average temperature drop rate and the total temperature drop amplitude in the target area, and then executing closed-loop control of the subsequent driving behavior based on the determination result. Specifically, this includes: The effectiveness of fire extinguishing actions is determined based on the average temperature drop rate and the total temperature drop in the target area. The fire extinguishing action is deemed effective if both of the following conditions are met: Condition 1: The average temperature drop rate is less than or equal to 0.5℃ / s; Condition 2: The total temperature drop in the target area is greater than or equal to 15℃. Otherwise, the fire extinguishing action is deemed ineffective if either of the above conditions is not met. When the fire extinguishing action is determined to be effective, the fire control panel disconnects the solenoid valve control circuit and records the current linkage event log. When the fire extinguishing action is determined to be invalid, the fire control panel will continue the spraying action and send a linkage failure signal to the BMS unit.

5. A battery pack thermal runaway protection system, applied to the battery pack thermal runaway protection method according to any one of claims 1 to 4, characterized in that, The battery pack thermal runaway protection system includes: The thermal runaway determination module is used to collect real-time operating parameters of the battery clusters in the target battery pack at time t for cell i through a preset BCU unit, and to determine whether the thermal runaway triggering conditions are met based on the real-time operating parameters using a continuous interval joint state mechanism, and output a thermal runaway identification flag. The system uses a continuous interval joint state mechanism based on real-time operating parameters to determine whether the thermal runaway triggering conditions are met, and outputs a thermal runaway identification flag. The steps specifically include: Real-time operating parameters include cell voltage Cell temperature and the rate of temperature rise per unit time Construct a continuous criterion set based on a sliding time window Δt, and determine whether the following three conditions are met simultaneously in the continuous criterion set: Condition 1: Within the sliding time window Δt, the cell voltage The minimum value is less than 2V and there is no disconnection process; Condition 2: Within the sliding time window Δt, the cell temperature The maximum value is greater than 80℃; Condition 3: Within the sliding time window Δt, there exists at least one time point. At the point in time The temperature rise rate per unit time is greater than or equal to 1℃ / s and lasts for more than 3s; If all three conditions above are met within the sliding time window Δt, then the thermal runaway identification flag will be output. Otherwise output ; Linkage signal output module, used for thermal runaway identification flag bit The corresponding electrical signal control command is generated, and the preset BCU unit outputs the electrical signal control command to the cluster-level solenoid valve control interface at the top of the battery cluster. At the same time, the real-time operating parameters and thermal runaway identification flag are also transmitted. Send to the superior BAU unit; The consistency verification module is used to acquire cell thermal runaway feedback data. The upper-level BAU unit performs multi-parameter fitting trend consistency detection and cross-node validity verification based on real-time operating parameters and spraying status feedback data, and outputs dry contact closure signal. ; Among these processes, the upper-level BAU unit acquires thermal runaway feedback data from the battery cell, performs multi-parameter fitting trend consistency detection and cross-node validity verification based on real-time operating parameters and spraying status feedback data, and outputs dry contact closure signals. The steps specifically include: Within the sliding time window Δt, the real-time operating parameters reported by the BCU unit are extracted, and the local operating parameters recorded by the BMS unit are collected. Based on the comparison of the real-time operating parameters reported by the BCU unit and the local operating parameters recorded by the BMS unit, the consistency of the three fitting trends is evaluated, and the dry contact closure signal is output based on the comparison result of the consistency of the three fitting trends. ; Specifically, the consistency of the three fitting trends is compared, and the dry contact closure signal is output based on the comparison result of the consistency of the three fitting trends. The specific steps include: The least squares linear fitting method was used to fit the cell temperature data in the real-time operating parameters to obtain the first temperature trend line; the least squares linear fitting method was used to fit the cell temperature data in the local operating parameters to obtain the second temperature trend line. The cell voltage data in the real-time operating parameters are fitted using a moving average combined with the first-order difference method to obtain the first voltage trend line; the cell voltage data in the local operating parameters are fitted using a moving average combined with the first-order difference method to obtain the second voltage trend line. Compare the consistency of the following three fitting trends: Condition 1: The fitting error in slope between the first temperature trend line and the second temperature trend line does not exceed the set first error threshold. ; Condition 2: The fitting error in slope between the first voltage trend line and the second voltage trend line does not exceed the set second error threshold. ; Condition 3: Obtain the spraying duration from the spraying status feedback data; the spraying duration must be greater than the set tolerance. ; If all three conditions are met, the real-time operating parameters reported by the BCU unit are deemed reliable, and a dry contact closure signal is output. Conversely, output dry contact closure signal. 0; The global linkage judgment module is used by the fire alarm control panel to receive dry contact closure signals. When the dry contact closes the signal When =1, determine whether the global spraying fire suppression linkage condition is met. If it is met, issue a full-cluster spraying fire suppression command and output the global protection status flag F. The fire extinguishing closed-loop control module is used to collect temperature data of the target area based on the preset infrared temperature measurement unit when the global protection status flag F is 1, calculate the average temperature drop rate of the target area within the preset continuous time window, and obtain the total temperature drop amplitude of the target area; perform fire extinguishing action effectiveness judgment based on the average temperature drop rate and the total temperature drop amplitude of the target area, and perform post-drive behavior closed-loop control based on the judgment result.

6. A battery pack thermal runaway protection device, characterized in that, The battery pack thermal runaway protection device includes: a memory, a processor, and a battery pack thermal runaway protection program stored in the memory and executable on the processor. When the battery pack thermal runaway protection program is executed by the processor, it implements a battery pack thermal runaway protection method according to any one of claims 1 to 4.

7. A computer program product, characterized in that, The computer program product includes a battery pack thermal runaway protection program, which, when executed by a processor, implements a battery pack thermal runaway protection method according to any one of claims 1 to 4.

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