A multi-sensor fusion-based energy storage PACK thermal runaway early detection safety protection system and device

Abstract

The application relates to the technical field of energy storage system safety monitoring, and discloses a multi-sensor fusion-based energy storage PACK thermal runaway early detection safety protection system and device, which comprises a battery management system and a battery control unit. The battery management system acquires temperature and voltage data in an energy storage PACK running state process and pressure, inclination angle and combustible gas concentration data in an environment state process, and outputs running state results and environment state results through operation. The battery control unit compares the results with a preset threshold matrix, outputs a graded thermal runaway state, and sends corresponding control instruction action sequences to a terminal monitoring system, an energy storage converter and an electronic explosion-proof valve. The electronic explosion-proof valve device is configured with a push-pull electromagnetic valve and a return spring, and has a mechanical passive exhaust and a controlled electric active exhaust double mechanism. The application realizes multi-dimensional state fusion early warning, can establish an exhaust channel in advance to reduce the risk of box rupture.

Description

Technical Field

[0001] This invention relates to the field of energy storage system safety monitoring technology, specifically to a safety protection system and device for early detection of thermal runaway in energy storage PACK based on multi-sensor fusion. Background Technology

[0002] In the field of safety monitoring of energy storage PACKs, conventional battery management systems mainly rely on real-time monitoring of electrical and thermodynamic parameters such as voltage and temperature. Because the electrical anomalies exhibited in the early stages of thermal runaway are relatively weak, and temperature acquisition points are typically located on the cell terminals or CCS plate surface, there is a time lag in heat conduction to the sensors. This makes it difficult to provide accurate early warnings before a violent chain reaction occurs in the battery by relying solely on voltage and temperature parameter monitoring.

[0003] Current energy storage enclosure safety protection structures typically employ passive mechanical explosion-proof valves. These devices only open when the pressure inside the enclosure rises to a preset physical threshold due to gas accumulation, directly overcoming the spring preload. This passive triggering mode lacks effective linkage with the system's logical monitoring level, failing to establish exhaust channels in the early stages of risk assessment and before the internal pressure reaches the destructive threshold. This easily leads to the accumulation of heat and harmful gases inside the enclosure.

[0004] Furthermore, existing technologies generally lack methods for capturing changes in the microscopic expansion force of individual cells within the battery module and the physical deformation characteristics of the casing. In the early stages of thermal runaway, gas evolution inside the cell causes radial expansion of the casing. If this change in physical stress cannot be monitored in real time, the system will struggle to obtain the complete multidimensional characteristics of the thermal runaway evolution. Simultaneously, due to the lack of logical overlap judgment for multidimensional abnormal parameters, existing protection strategies often manifest as simple alarm or power-off actions, failing to execute graded linkage sequences such as power reduction operation, active venting, and hardware shutdown based on the degree of risk evolution. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a safety protection system and device for early detection of thermal runaway in energy storage PACKs based on multi-sensor fusion, which solves the problems of single-dimensional thermal runaway monitoring, lack of early physical parameter capture, and delayed safety linkage response in existing technologies.

[0006] To achieve the above objectives, the present invention provides the following technical solution: The first aspect of this invention provides a safety protection system for early detection of thermal runaway in energy storage PACKs based on multi-sensor fusion, comprising: The system comprises a battery management system and a battery control unit. The battery management system acquires data during the operation of the energy storage PACK and during its environmental conditions. The data during the operation includes at least temperature and voltage data; the data during the environmental conditions includes at least pressure, tilt angle, and combustible gas concentration data. Based on this data, the battery management system performs calculations to extract parameters such as the temperature difference between the current and previous sampling times, the temperature difference between individual cells, and the dynamic voltage difference. It outputs operational status results, including values ​​from calculation models for the temperature rise rate, temperature difference, and dynamic voltage difference. Simultaneously, based on the environmental data, the battery management system performs calculations to extract parameters such as pressure changes at different sampling times, the absolute pressure difference between modules, and the deflection angle. It outputs environmental status results, including values ​​from calculation models for the pressure change rate, module pressure difference, and tilt angle change. The battery control unit is used to receive the operating status result and the environmental status result, compare the operating status result and the environmental status result with the preset threshold matrix stored in the system, and output the thermal runaway state of the energy storage system.

[0007] Furthermore, the safety protection system is equipped with a terminal monitoring system, an energy storage converter, and an electronic explosion-proof valve. The thermal runaway state of the energy storage system output by the battery control unit is divided into three levels: Level 1, Level 2, and Level 3. In Level 1, the system triggers a response for a single abnormal dimension such as temperature difference, pressure difference, pressure differential, or tilt, controlling the terminal monitoring system to keep the yellow indicator light constantly on and output a warning message. In Level 2, the system triggers a response for severe single-dimensional abnormalities or logic and signals composed of preset parameters (such as the coupling of pressure difference alarm and tilt alarm), controlling the yellow indicator light to flash, sending a power reduction operation control command to the energy storage converter, and simultaneously outputting an active exhaust drive level to the electronic explosion-proof valve, controlling the electronic explosion-proof valve to mechanically open and perform smoke and gas exhaust actions. In the Level 3 warning state, the system determines the overlapping and coupled state of multiple high-risk factors (such as the logic and signal combination of temperature rise rate alarm and temperature, pressure rate or combustible gas alarm), controls the red indicator light to flash, controls the electronic explosion-proof valve to automatically open, and sends a hardware linkage command to the fire alarm system to cut off the AC and DC power supply and start the fire extinguishing and smoke exhaust operations.

[0008] In addition, the safety protection system acquires environmental status data through a pre-defined physical structure deployment. The system employs a circular thin-film pressure sensor installed in the gap between the outermost individual cell and the module end plate within the battery module inside the energy storage PACK. A pre-tightening force reference value is obtained through mechanical fasteners to capture changes in radial expansion compression resistance when the internal individual cell undergoes local expansion. An tilt sensor is physically anchored to the rigid inner wall or bottom plate of the energy storage PACK enclosure to measure the deflection angle. A gas-absorbing combustible gas sensor is installed on the internal gas flow channel to capture changes in combustible gas concentration.

[0009] The second aspect of this invention provides a multi-sensor fusion-based early detection safety protection device for thermal runaway in energy storage PACKs, applied to the multi-sensor fusion-based early detection safety protection system for thermal runaway in energy storage PACKs described in the first aspect. This device is manifested as an electronic explosion-proof valve independently fixed to the side wall of the energy storage PACK enclosure. The electronic explosion-proof valve includes: a support connecting seat, a push-pull solenoid valve, a vent valve body, a return spring, and a spring fixing seat. The outer surface of the support connecting seat is machined with external threads for threaded connection with the side wall shell of the energy storage PACK enclosure, and an internal rigid support structure is constructed. The push-pull solenoid valve is mounted on the rigid support structure and is equipped with an electromagnetic coil and a moving iron core push rod. One end of the vent valve body communicates with the interior of the energy storage PACK enclosure, and the other end communicates with the external environment. Its axial direction is parallel to and concentrically arranged with the linear extension and retraction direction of the moving iron core push rod. The central connecting rod of the vent valve body is mechanically connected to and displacement-limited by the spring fixing seat. The return spring is installed between the outer end face of the push-pull solenoid valve and the spring fixing seat. This device integrates both mechanical passive venting and electric active venting mechanisms. Under normal conditions, the vent valve body is pressed tightly against the sealing surface by the physical pressure applied by the return spring to maintain airtightness. When the absolute air pressure inside the energy storage PACK box rises to overcome the mechanical preload pressure of the return spring, the vent valve body compresses the return spring, disengaging from the sealing surface and opening the physical venting channel. When the solenoid coil of the push-pull solenoid valve receives the drive level from the system and is energized, the moving iron core push rod extends axially, overcoming the resistance of the return spring and forcibly pushing open the vent valve body to actively open the venting channel.

[0010] This invention provides a safety protection system and device for early detection of thermal runaway in energy storage PACKs based on multi-sensor fusion. It has the following beneficial effects: 1. This invention achieves multi-dimensional state monitoring of energy storage PACK by acquiring temperature and voltage data during operation, as well as pressure, tilt angle, and combustible gas concentration data during environmental conditions. The circular thin-film pressure sensor installed on the module end plate can capture the change in extrusion resistance caused by the radial expansion of individual cells in real time, making up for the lack of traditional battery management systems in monitoring the microscopic physical deformation of cells and improving the accuracy of detecting early physical characteristics of thermal runaway.

[0011] 2. This invention configures a preset threshold matrix and establishes a three-level thermal runaway early warning judgment logic based on the monitoring results of dimensions such as temperature rise rate, pressure change rate, and multi-parameter coupling state. By executing a logical AND-OR operation sequence through the battery control unit, different levels of risk states are directly mapped to specific actions of the terminal monitoring system, such as the yellow indicator light remaining on, the yellow indicator light flashing, and the red indicator light flashing. Simultaneously, the energy storage converter is linked to reduce power or cut off the power supply, thus standardizing the automated action sequence of the safety protection system.

[0012] 3. The electronic explosion-proof valve used in this invention integrates a support connecting seat, a push-pull solenoid valve, and a vent valve body. It has a dual action mechanism of mechanical passive venting and electric active venting. After receiving a level 2 or level 3 warning command, it can use the mechanical thrust of the moving iron core push rod to overcome the resistance of the reset spring and actively push open the vent valve body before the internal air pressure reaches the mechanical pre-tightening pressure threshold. This effectively reduces the risk of physical explosion of the energy storage PACK box caused by the accumulation of heat and gas. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the control method of the present invention; Figure 2 This is a schematic diagram of the module of the present invention equipped with a pressure sensor; Figure 3 This is a schematic diagram of the electronic explosion-proof valve of the present invention; Figure 4 This is a comparison diagram of the discharge curves of the present invention; Figure 5 This is a comparison chart of the charging curves of the present invention; Figure 6 This is a line graph showing the voltage-breaking stress values ​​of multiple individual cells tested according to the present invention. Detailed Implementation

[0014] The technical solutions in 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.

[0015] See attached document Figure 1 This invention provides a multi-sensor fusion-based early detection and safety protection system for thermal runaway in energy storage PACKs, which may include: a battery management system, a battery control unit, an energy storage converter, a terminal monitoring system, and a fire suppression system. Each PACK is connected in series and connected to a control box via an input port. The control box houses a cluster battery BMS control system and a BDU component. The cluster battery BMS control system and BDU component are configured to perform detection and control of the battery clusters.

[0016] The modules are arranged on the upper side of the PACK enclosure. The slave control board and multiple sensors are sequentially mounted on the lower side of the PACK enclosure. The CCS communication harness of each module is connected to the slave control board.

[0017] Based on the aforementioned system hardware architecture, this system is configured to execute a state-based dual-track analysis and control process using multi-dimensional data. The battery management system is configured to acquire data during the energy storage PACK's operational state and environmental state.

[0018] The battery management system performs calculations based on data collected during the operation of the energy storage PACK and outputs the operation status results. This data includes internal temperature, voltage, and current data of the energy storage PACK, as well as data from the liquid cooling system.

[0019] In the calculation step of outputting the operating status results, the battery management system calculates the temperature rise rate and the temperature difference of individual cells based on the extracted temperature data.

[0020] Define the current sampling time as The sampling period is The temperature value at the current sampling time is The temperature value at the previous sampling time was The rate of temperature rise is defined as The rate of temperature rise The calculation formula is: ; The energy storage PACK is defined to be equipped with The temperature collection point, the first The temperature value of each temperature sampling point at the current sampling time is , The value range is 1 to A positive integer. The temperature difference inside the energy storage PACK is defined as... The temperature difference The calculation formula is: ; The battery management system acquires the dynamic voltage difference of individual cells in real time. The dynamic voltage difference of an individual cell is defined as... The dynamic voltage difference Used to indicate the voltage deviation between individual cells within the monitored battery pack.

[0021] The battery management system performs calculations based on data from the energy storage PACK environmental status process and outputs environmental status results. The data from the environmental status process includes pressure data, tilt angle data, and combustible gas concentration data within the energy storage PACK. In the calculation step for outputting the environmental status results, the battery management system calculates the pressure change rate and module pressure difference based on the extracted pressure data.

[0022] The current sampling time is defined as The pressure value at the current sampling time is The pressure value at the previous sampling time was The rate of pressure change is defined as The rate of pressure change. The calculation formula is: ; The battery management system calculates the pressure difference between different modules. The pressure value of the detected abnormal module is defined as... The reference pressure value for a normal module is The module pressure difference is defined as The module pressure difference The calculation formula is: ; The battery management system calculates the tilt angle change based on the extracted tilt angle data. The initial installation tilt reference angle of the energy storage PACK is defined as... The absolute tilt angle monitored in real time is The change in tilt angle is defined as The change in tilt angle The calculation formula is: ; The battery management system sends the operating status results and environmental status results, including the calculated values ​​mentioned above, to the battery control unit. The operating status results include the aforementioned temperature rise rate. Temperature difference Dynamic voltage difference It includes data on the operating status of the cooling system, the charging and discharging status of the battery, and the battery health status.

[0023] The environmental condition results include the aforementioned pressure change rate. Module pressure difference Change in tilt angle The data includes absolute pressure values ​​and combustible gas concentration values. The battery control unit receives the operating status results and the environmental status results. The battery control unit executes a logic comparison program, comparing the operating status results and the environmental status results with a preset threshold matrix stored in the system, and outputs the thermal runaway state of the energy storage system.

[0024] The battery control unit sends early warning information to the terminal monitoring system based on the different danger levels corresponding to the thermal runaway state of the output energy storage system, and sends a sequence of control command actions to the energy storage converter, the fire protection system and the exhaust linkage mechanism.

[0025] See attached document Figure 2 The security protection system of the present invention includes an operation status monitoring module and an environmental status monitoring module in its hardware architecture.

[0026] The operational status monitoring module is built upon the inherent data acquisition network within the battery module. The battery module comprises multiple individual cells arranged longitudinally and a CCS board covering the top of each individual cell.

[0027] The CCS board is equipped with battery connection terminals and temperature acquisition points. The voltage acquisition module is physically connected to the positive and negative terminals of each individual battery cell through the battery connection terminals.

[0028] A distributed temperature sensor is integrated at the temperature acquisition point. The probe of the distributed temperature sensor is attached to the surface of the terminal post or casing of the individual battery cell, configured to acquire the thermodynamic temperature of the individual battery cell surface. The CCS board is connected to the slave control board of the battery management system via a ribbon cable.

[0029] The liquid cooling control module is connected in series in the liquid cooling circuit of the energy storage PACK. The liquid cooling control module is connected to the battery management system via a communication bus and is configured to acquire and upload data on the on / off status, and full-load operation status of the cooling system.

[0030] In the hardware deployment of the environmental condition monitoring module, a pressure sensing network was added to the system to obtain internal mechanical stress data. (Continue referring to the appendix...) Figure 2 In this embodiment, a circular thin-film pressure sensor is used. The specified model of this pressure sensor is RP-D4046, the diameter of the force-bearing surface of the sensor is 46mm, and the range is limited to 200kPa to 5MPa.

[0031] The circular thin-film pressure sensor is installed in the gap between the outermost single cell and the module end plate within the battery module. Specifically, the first circular pressure sensor is installed between the front end plate of the module and the side of the first single cell; the second circular pressure sensor is installed between the rear end plate of the module and the side of the last single cell.

[0032] The end plate and side plate of the module are connected by mechanical fasteners, thus fixing the entire module structure. Through this mechanical clamping structure, the circular thin-film pressure sensor acquires a preload reference value during initial assembly. When the internal individual battery cells undergo microscopic expansion or deformation, the radial expansion displacement directly compresses the circular thin-film pressure sensor, causing it to output a change in resistance or capacitance. The pressure sensor's data acquisition cable is equipped with a quick-connect connector, which directly plugs into a reserved interface on the CCS board.

[0033] Multiple battery modules are arranged in an array in the upper space inside the PACK housing. The lower space inside the PACK housing houses the slave control board and multiple environmental sensors. The CCS communication harness of each battery module converges and connects to the input terminal of the slave control board.

[0034] The tilt sensor is physically anchored to the rigid inner wall or bottom plate of the PACK enclosure by bolts or adhesive. The tilt sensor is configured to measure the tilt angle of the PACK enclosure relative to the direction of gravitational acceleration when it is subjected to external mechanical impact or structural torsional deformation.

[0035] The combustible gas detector is an aspirating combustible gas sensor. It is installed in the gas flow channel or top space inside the PACK enclosure. The air inlet of the combustible gas detector is exposed to the internal environment of the PACK and is configured to capture and measure the concentration of combustible gas in the enclosure air when electrolyte vaporizes and is discharged due to internal rupture of a single battery cell.

[0036] The tilt sensor and the combustible gas detector's signal output terminals are connected to the acquisition interface of the slave control board via internal wiring harnesses. Furthermore, the spring-loaded retaining cover of the electronic explosion-proof valve is mounted from the outside in on the side wall of the PACK enclosure, and the electromagnetic coil control harness of the electronic explosion-proof valve is also connected to the slave control board, receiving control signals from the underlying drive signal of the battery management system.

[0037] See attached document Figure 3 The energy storage system of this invention is equipped with a core safety linkage mechanism, specifically including an electronic explosion-proof valve. The electronic explosion-proof valve is configured to be independently installed on the PACK enclosure, or it can be separate from a conventional mechanical explosion-proof valve and independently installed on the wall of the PACK enclosure.

[0038] The physical structure of the electronic explosion-proof valve includes three main components: a support connector, a vent valve body, and a push-pull solenoid valve. The outer surface of the support connector is machined with external threads. The support connector engages with the side wall of the PACK enclosure via these external threads, forming a mechanically fixed and physically sealed connection.

[0039] The support connector has a rigid support structure built inside. The push-pull solenoid valve is installed on the rigid support structure inside the support connector. The push-pull solenoid valve serves to fix and support the valve and drive it to generate force inside the support connector. The push-pull solenoid valve is equipped with an electromagnetic coil and a moving iron core push rod. The linear extension and retraction direction of the push rod is parallel to the axial direction of the vent valve body, and the mechanical assembly structure of the two is concentrically arranged.

[0040] One end of the vent valve body is connected to the interior of the PACK housing, and the other end is connected to the external environment. The electronic explosion-proof valve is internally equipped with a return spring and a spring retainer. The central connecting rod of the vent valve body is mechanically connected to and has displacement limited by the spring retainer. The inner end face of the push-pull solenoid valve is connected to the main valve body, and the return spring is installed between the outer end face of the push-pull solenoid valve and the spring retainer.

[0041] Based on the above physical structure, the electronic explosion-proof valve is equipped with a dual-action mechanism of mechanical passive venting and electric active venting. Under normal conditions, without initial control signal input, the vent valve body is subjected to continuous physical pressure applied by the return spring. The vent valve body is pressed tightly against the sealing surface of the main valve body by this spring pressure, maintaining the overall airtightness of the electronic explosion-proof valve and the PACK enclosure.

[0042] In the mechanical passive venting process, when abnormal venting occurs inside the PACK housing, causing a continuous rise in internal air pressure, the high-pressure gas acts directly on the inner surface of the vent valve body. When the absolute value of the outward thrust generated by this gas pressure exceeds the mechanical preload pressure of the return spring, the gas thrust compresses the return spring. The vent valve body then undergoes axial displacement and disengages from the sealing surface, opening the physical venting channel for mechanical venting.

[0043] In the electric active exhaust process, when the system receives a level 2 or level 3 warning command, the battery management system outputs a drive current to the push-pull solenoid valve. The solenoid coil inside the push-pull solenoid valve is energized, generating electromagnetic thrust. This electromagnetic thrust drives the moving iron core push rod to extend axially, overcoming the elastic resistance of the return spring and compressing it. The moving iron core push rod forcibly pushes open the vent valve body, actively opening the exhaust channel for electric exhaust. This mechanism is configured to establish an exhaust and smoke extraction channel in advance, independent of the internal absolute pressure value, during the early stages of thermal runaway.

[0044] See attached document Figure 4 and attached Figure 5 The battery control unit of this invention is equipped with a state assessment model based on multi-dimensional data, which receives the operating state results and environmental state results output from the previous processing stage, and performs feature extraction and threshold comparison judgment. During the determination of operating state data, the battery control unit performs benchmark comparison logic based on the distribution of temperature, electrical, and health state dimensions.

[0045] Regarding the temperature dimension, the battery management system performs calculations based on the temperature data. Specifically, based on the temperature data, it calculates the absolute difference between the temperature value at the current sampling time and the temperature value at the previous sampling time, divides it by the sampling period, and obtains a temperature rise rate calculation model. Simultaneously, it acquires the temperature values ​​of multiple temperature sampling points within the energy storage PACK at the current sampling time, calculates the difference between the highest and lowest temperature values, and obtains a temperature difference calculation model. The battery control unit judges the received absolute temperature value and temperature rise rate. The system is configured with a preset absolute temperature alarm threshold, which is set to 60℃. When the extracted absolute temperature value is greater than or equal to 60℃, the system outputs a temperature alarm. The system is also configured with a first preset temperature rise rate threshold.

[0046] In addition, when the temperature difference value output by the temperature difference calculation model reaches the preset temperature difference thresholds at each level, the corresponding temperature difference alarm is triggered.

[0047] Regarding temperature difference, the battery control unit incorporates a three-level temperature difference alarm benchmark, based on national and industry standards stipulating that the overall temperature difference of a liquid cooling system should be less than or equal to 3℃ and the maximum temperature difference of an air-cooled system should be less than or equal to 5℃. The specific comparison and execution logic is as follows: when the calculated temperature difference of a single battery cell is greater than or equal to 3℃ and less than 5℃, a level one temperature difference alarm is triggered; when the temperature difference is greater than or equal to 5℃ and less than 8℃, a level two temperature difference alarm is triggered; and when the temperature difference is greater than or equal to 8℃, a level three temperature difference alarm is triggered.

[0048] For the voltage dimension, the battery management system performs calculations based on the voltage data. Specifically, it acquires the voltage values ​​of multiple individual cells within the energy storage PACK at the current sampling time, calculates the difference between the highest and lowest voltage values, and obtains a dynamic voltage difference calculation model. The system monitors the voltage deviation output by the dynamic voltage difference calculation model in real time. When the difference reaches a set threshold, the system determines that a voltage difference alarm exists.

[0049] Continue to refer to the appendix Figure 4 and attached Figure 5From an electrical perspective, the battery control unit monitors the dynamic voltage difference between individual cells. Based on actual deviations during charging and discharging, at near 100% battery charge, the voltage difference between normal and abnormal cells deviates by 110mV; at near 0% battery charge, the deviation is 260mV. The system is configured with a three-level dynamic voltage difference judgment standard: a level 1 alarm is triggered when the dynamic voltage difference is greater than or equal to 100mV and less than 200mV; a level 2 alarm is triggered when the dynamic voltage difference is greater than or equal to 200mV and less than 300mV; and a level 3 alarm is triggered when the dynamic voltage difference is greater than or equal to 300mV.

[0050] For the State of Health (SOH) dimension, the battery control unit configures multiple benchmarks based on the actual cycle degradation physical characteristics of the cell. A battery capacity between 95% and 100% indicates normal electrochemical performance; between 85% and 95% indicates normal capacity degradation and stable performance; between 75% and 85% indicates increased internal impedance and reduced efficiency; and below 75% indicates severe internal degradation and a risk of structural failure. Based on these characteristics, the system's SOH judgment logic is as follows: when the actual SOH value is less than 95% but greater than or equal to 85%, a level 1 SOH alarm is output; when the SOH value is less than 85% but greater than or equal to 75%, a level 2 SOH alarm is output; and when the SOH value is less than 75%, a level 3 SOH alarm is output.

[0051] See attached document Figure 6 In the process of determining environmental state data, the battery control unit assesses the values ​​for pressure, physical location, and gas concentration. For the pressure dimension, the battery control unit extracts the absolute pressure value and its changing state parameters. Based on the attached... Figure 6 The system compares the pressure value at which the internal CID (Current Interrupt Device) of the cylindrical battery disconnects with the physical failure pressure value at which the explosion-proof valve of the square battery opens. It extracts 980 kPa as the absolute benchmark for the third-level pressure alarm of the cell's physical failure, and uses increments of 100 kPa to progressively decrease the benchmarks for the second and first-level alarms. The specific comparison logic is as follows: when the collected absolute pressure value is greater than or equal to 780 kPa and less than 880 kPa, a first-level pressure alarm is output; when the absolute pressure value is greater than or equal to 880 kPa and less than 980 kPa, a second-level pressure alarm is output; and when the absolute pressure value is greater than or equal to 980 kPa, a third-level pressure alarm is output.

[0052] Meanwhile, for the dynamic pressure change parameter, the system is configured with a preset threshold of 10 kPa / s for pressure rate change. When the monitored and calculated pressure rate change is greater than or equal to 10 kPa / s, a pressure rate alarm is triggered. The system is configured with a preset threshold of 200 kPa for module pressure difference. When the physical pressure difference between the abnormal module and the normal module is greater than or equal to 200 kPa, it indicates that asymmetric expansion has occurred in a local module, triggering a pressure difference alarm.

[0053] For the physical spatial location and gas concentration dimensions, the system receives the change in tilt angle and the absolute concentration of combustible gas. The system has a built-in absolute tilt deflection threshold of 1°. When the monitored tilt angle change value is greater than 1°, it is determined that the PACK enclosure has physical deformation or forced displacement, and a tilt alarm is output. The battery control unit stores a combustible gas safety threshold value. When the real-time gas concentration value fed back by the combustible gas sensor exceeds the safety threshold value, a combustible gas alarm is output.

[0054] For the physical spatial location and gas concentration dimensions, the system receives the tilt angle change and the absolute concentration parameters of combustible gas. The calculation logic for the tilt angle change is as follows: based on the tilt angle data, the absolute difference between the real-time monitored absolute tilt angle and the initial installation tilt reference angle of the energy storage PACK is calculated to obtain the tilt angle change calculation model. The system has a built-in tilt deflection absolute threshold of 1°. When the monitored tilt angle change value is greater than 1°, it is determined that there is physical deformation or forced displacement of the PACK enclosure, and a tilt alarm is output.

[0055] The battery control unit of this invention is equipped with a thermal runaway graded early warning logic module. The battery control unit receives alarm status input signals from the aforementioned dimensions and executes a comparison procedure for the thermal runaway truth table of the energy storage system. Through multiple configured sets of logical OR and AND operations, the battery control unit precisely classifies the thermal runaway state of the energy storage system into three independent levels: Level 1, Level 2, and Level 3 early warning, and outputs corresponding level safety linkage strategy instructions to each actuator.

[0056] The battery control unit executes a first-level early warning comparison logic. When the system receives any single alarm signal from the following categories: temperature difference first-level alarm, temperature difference second-level alarm, pressure difference first-level alarm, pressure difference second-level alarm, SOH first-level alarm, SOH second-level alarm, pressure difference alarm, tilt alarm, and pressure first-level alarm, or when it receives a combination of the above alarm signals, the battery control unit determines and outputs a first-level early warning status for thermal runaway of the energy storage system.

[0057] In response to the first-level thermal runaway warning state of the energy storage system, the battery control unit sends a first-level linkage execution command to the terminal monitoring system. Upon receiving this command, the terminal monitoring system keeps the yellow indicator light on its panel constantly lit and simultaneously controls the terminal monitoring display screen to output the corresponding first-level warning text message.

[0058] The battery control unit executes a two-level early warning comparison logic. When the system receives any single alarm signal from the following categories: temperature difference level 3 alarm, pressure difference level 3 alarm, SOH level 3 alarm, temperature rise rate alarm, temperature alarm, pressure rate alarm, combustible gas alarm, pressure level 2 alarm, or pressure level 3 alarm, or when the system simultaneously receives a logic AND signal consisting of a pressure difference alarm and a tilt alarm, the battery control unit determines and outputs a level 2 early warning state for thermal runaway of the energy storage system.

[0059] In response to the second-level thermal runaway warning state of the energy storage system, the battery control unit sends a second-level linkage execution command to multiple physical execution nodes. Upon receiving the command, the terminal monitoring system controls the yellow indicator light to flash and controls the display screen to output the second-level alarm text information. Simultaneously, the battery control unit sends a power reduction operation control command to the energy storage converter (PCS) to reduce the charging and discharging current parameters of the energy storage PACK. Furthermore, the battery control unit outputs an active venting drive level to the electronic explosion-proof valve mounted on the PACK enclosure. This active venting drive level energizes the push-pull solenoid valve inside the electronic explosion-proof valve, generating thrust that mechanically pushes the vent valve body open, initiating venting and smoke extraction preparation actions.

[0060] The battery control unit executes a three-level early warning comparison logic. This logic is configured to jointly determine the overlapping and coupled states of multiple high-risk factors. When the system receives a logic and signal combination consisting of any one of the following: temperature rise rate alarm and temperature alarm, temperature rise rate alarm and pressure rate alarm, temperature rise rate alarm and combustible gas alarm, temperature rise rate alarm and pressure level 3 alarm, temperature alarm and pressure rate alarm, temperature alarm and combustible gas alarm, temperature alarm and pressure level 3 alarm, pressure rate alarm and combustible gas alarm, pressure rate alarm and pressure level 3 alarm, or combustible gas alarm and pressure level 3 alarm, the battery control unit determines and outputs a three-level early warning state for thermal runaway of the energy storage system.

[0061] In response to the Level 3 thermal runaway warning state of the energy storage system, the battery control unit sends a Level 3 linkage execution command to the highest priority execution node. Upon receiving the command, the terminal monitoring system controls the red indicator light to flash and controls the display screen to output Level 3 alarm text information. The battery control unit outputs a drive level to the electronic explosion-proof valve to control its automatic opening. Simultaneously, the battery control unit sends a hardware linkage command to the external fire alarm system. Upon receiving this linkage command, the fire alarm system disconnects the AC / DC power supply physical circuits of the energy storage system and simultaneously sends a start trigger level to the fire extinguishing system and smoke extraction system to perform physical fire extinguishing and forced smoke extraction operations.

Claims

1. A safety protection system for early detection of thermal runaway in energy storage PACK based on multi-sensor fusion, characterized in that, include: Battery management system, battery control unit, terminal monitoring system, energy storage converter, and electronic explosion-proof valve; The battery management system is used to acquire data during the operation of the energy storage PACK and the environmental status of the energy storage PACK. The battery management system performs calculations based on the data during the operation of the energy storage PACK and outputs the operation status results. The data during the operation of the energy storage PACK includes at least temperature data and voltage data. The battery management system performs calculations based on the data during the environmental status of the energy storage PACK and outputs the environmental status results. The data during the environmental status of the energy storage PACK includes at least pressure data, tilt angle data, and combustible gas concentration data. The battery control unit is used to receive the operating status result and the environmental status result, compare the operating status result and the environmental status result with the preset threshold matrix stored in the system, and output the thermal runaway state of the energy storage system. The battery control unit is used to send corresponding control command action sequences to the terminal monitoring system, the energy storage converter, and the electronic explosion-proof valve according to the thermal runaway state of the energy storage system, so as to perform physical safety protection operations.

2. The safety protection system for early detection of thermal runaway in energy storage PACK based on multi-sensor fusion according to claim 1, characterized in that, The battery management system performs calculations based on data from the energy storage PACK's operating status and outputs the operating status results. The specific execution logic of the calculations includes: Based on the temperature data, the absolute difference between the temperature value at the current sampling time and the temperature value at the previous sampling time is calculated, and then divided by the sampling period to obtain the temperature rise rate calculation model. Based on the temperature data, the temperature values ​​of multiple temperature acquisition points inside the energy storage PACK at the current sampling time are obtained, and the difference between the highest and lowest temperature values ​​is calculated to obtain a temperature difference calculation model. Based on the voltage data, the voltage values ​​of multiple individual cells inside the energy storage PACK at the current sampling time are obtained, the difference between the highest voltage value and the lowest voltage value is calculated, and a dynamic voltage difference calculation model is obtained. The operating status results include the output values ​​of the temperature rise rate calculation model, the temperature difference calculation model, and the dynamic voltage difference calculation model, as well as battery charge and discharge status data, cooling system operating status data, and battery health status data.

3. The safety protection system for early detection of thermal runaway in energy storage PACK based on multi-sensor fusion according to claim 1, characterized in that, The battery management system performs calculations based on data from the energy storage PACK environmental state process and outputs environmental state results. The specific execution logic of the calculations includes: Based on the pressure data, the difference between the pressure value at the current sampling time and the pressure value at the previous sampling time is calculated, and divided by the sampling period to obtain the pressure change rate calculation model. The absolute difference between the monitored abnormal module pressure value and the normal module reference pressure value is calculated to obtain the module pressure difference calculation model; Based on the tilt angle data, the absolute difference between the real-time monitored absolute tilt angle and the initial installation tilt reference angle of the energy storage PACK is calculated to obtain the tilt angle change calculation model. The environmental status results include the output values ​​of the pressure change rate calculation model, the module pressure difference calculation model, and the tilt angle change calculation model, and include absolute pressure values ​​and absolute concentration parameters of combustible gas.

4. The energy storage PACK thermal runaway early detection safety protection system based on multi-sensor fusion according to claim 1, characterized in that, The preset threshold matrix includes multi-dimensional hierarchical safety thresholds set for the operating status results and the environmental status results; The battery control unit is configured to generate a corresponding alarm signal when the operating status result or the environmental status result reaches the corresponding multi-dimensional hierarchical safety threshold. The alarm signals include: temperature difference level 1 to 3 alarms based on the output values ​​of the temperature difference calculation model, pressure difference level 1 to 3 alarms based on the output values ​​of the dynamic voltage difference calculation model, battery health status level 1 to 3 alarms based on battery health status data, pressure level 1 to 3 alarms based on absolute pressure values, and temperature rise rate alarm, temperature alarm, pressure rate alarm, pressure difference alarm, tilt alarm and combustible gas alarm triggered based on the calculation results of corresponding parameters. The thermal runaway state of the energy storage system output by the battery control unit is divided into a first-level warning state, a second-level warning state, and a third-level warning state based on the alarm signal; The battery control unit is used to send corresponding control command action sequences to the terminal monitoring system, the energy storage converter, and the electronic explosion-proof valve according to the different hazard levels of the thermal runaway state of the energy storage system.

5. A safety protection system for early detection of thermal runaway in an energy storage PACK based on multi-sensor fusion as described in claim 4, characterized in that, The determination criteria and action sequence for the Level 1 warning status include: When the system receives any single alarm signal from the following categories: temperature difference level 1 alarm, temperature difference level 2 alarm, pressure difference level 1 alarm, pressure difference level 2 alarm, battery health status level 1 alarm, battery health status level 2 alarm, pressure difference alarm, tilt alarm, and pressure level 1 alarm, or a combination of the above alarm signals, the battery control unit determines and outputs the level 1 warning status. In response to the Level 1 warning status, the battery control unit sends a Level 1 linkage execution command to the terminal monitoring system, controlling the terminal monitoring system to turn on the yellow indicator light and output Level 1 warning text information.

6. A safety protection system for early detection of thermal runaway in an energy storage PACK based on multi-sensor fusion as described in claim 4, characterized in that, The determination criteria and action sequence for the Level 2 warning status include: When the system receives any single alarm signal from the following categories: temperature difference level 3 alarm, pressure difference level 3 alarm, battery health status level 3 alarm, temperature rise rate alarm, temperature alarm, pressure rate alarm, combustible gas alarm, pressure level 2 alarm, or pressure level 3 alarm, or when the system simultaneously receives a logical AND signal consisting of a pressure difference alarm and a tilt alarm, the battery control unit determines and outputs the level 2 warning status. In response to the level 2 warning state, the battery control unit sends a level 2 linkage execution command to the terminal monitoring system to make the yellow indicator light flash and output level 2 alarm text information. At the same time, it sends a power reduction operation control command to the energy storage converter and outputs an active exhaust drive level to the electronic explosion-proof valve to control the electronic explosion-proof valve to mechanically push open and perform smoke and exhaust actions.

7. A safety protection system for early detection of thermal runaway in energy storage PACK based on multi-sensor fusion according to claim 4, characterized in that, It also includes a fire alarm system; the determination conditions and action sequence for the three-level early warning status include: When the system receives a logic and signal combination consisting of any one of the following: temperature rise rate alarm and temperature alarm, temperature rise rate alarm and pressure rate alarm, temperature rise rate alarm and combustible gas alarm, temperature rise rate alarm and pressure level 3 alarm, temperature alarm and pressure rate alarm, temperature alarm and combustible gas alarm, temperature alarm and pressure level 3 alarm, pressure rate alarm and combustible gas alarm, pressure rate alarm and pressure level 3 alarm, combustible gas alarm and pressure level 3 alarm, the battery control unit determines and outputs the level 3 warning status. In response to the three-level warning state, the battery control unit sends a three-level linkage execution command to the terminal monitoring system to make the red indicator light flash, outputs a drive level to the electronic explosion-proof valve to control its automatic opening, and sends a hardware linkage command to the fire alarm system to cut off the AC and DC power supply and start the fire extinguishing and smoke exhaust operations.

8. A safety protection system for early detection of thermal runaway in energy storage PACK based on multi-sensor fusion as described in claim 1, characterized in that, The hardware physical deployment structure used in the process of acquiring the environmental status of the energy storage PACK includes: A circular thin-film pressure sensor is installed in the gap between the outermost single cell and the module end plate inside the battery module of the energy storage PACK. It obtains the pre-tightening force reference value through mechanical fasteners and is configured to capture the impedance change of radial expansion and compression when the internal single cell undergoes local expansion and transmit the physical pressure data to the battery management system.

9. A safety protection system for early detection of thermal runaway in energy storage PACK based on multi-sensor fusion as described in claim 1, characterized in that, The hardware physical deployment structure used in the process of acquiring the environmental status of the energy storage PACK also includes: The tilt sensor is physically anchored to the rigid inner wall or bottom plate of the energy storage PACK enclosure and is used to measure the deflection angle relative to the direction of gravity when the energy storage PACK is subjected to external mechanical impact. An aspirating combustible gas sensor is installed on the gas flow channel inside the energy storage PACK box. The air inlet of the aspirating combustible gas sensor is exposed to the internal environment of the box and is used to capture changes in the concentration of combustible gas caused by the exhaust of battery electrolyte. The signal output terminals of the tilt sensor and the aspirating combustible gas sensor are connected to the battery management system via a communication harness.

10. A safety protection device for early detection of thermal runaway in an energy storage PACK based on multi-sensor fusion, wherein the device is an electronic explosion-proof valve in the safety protection for early detection of thermal runaway in an energy storage PACK based on multi-sensor fusion as described in any one of claims 1-9, comprising: The support connection seat has external threads machined on its outer surface, which are used to make threaded connection with the side wall shell of the energy storage PACK box through the external threads. The support connection seat has a rigid support structure built inside. A push-pull solenoid valve is installed on the rigid support structure inside the support connecting seat. The push-pull solenoid valve is equipped with an electromagnetic coil and a moving iron core push rod. The vent valve body has one end connected to the interior of the energy storage PACK box and the other end connected to the external environment. The axial direction of the vent valve body is parallel to and concentrically arranged with the linear extension and retraction direction of the moving iron core push rod. The return spring and the spring fixing seat are mechanically connected and displacement limited by the central connecting rod of the vent valve body and the spring fixing seat. The return spring is installed between the outer end face of the push-pull solenoid valve and the spring fixing seat. Under normal conditions without control signal input, the vent valve body is pressed tightly against the sealing surface by the physical pressure applied by the return spring to maintain airtightness. When the absolute value of the outward thrust generated by the air pressure inside the energy storage PACK box is greater than the mechanical preload pressure of the return spring, the vent valve body is used to compress the return spring and disengage from the sealing surface to open the physical exhaust channel. When the electromagnetic coil of the push-pull solenoid valve receives the active exhaust drive level output by the system, the moving iron core push rod extends axially, overcoming the resistance of the return spring to forcibly push open the vent valve body to actively open the exhaust channel.

Images