Lithium battery thermal runaway early warning and fire extinguishing integrated system

Abstract

The invention discloses a lithium battery thermal runaway early warning and fire extinguishing integrated system, which relates to the technical field of battery safety, and comprises an early warning subsystem, a fire extinguishing subsystem, an oxygen consumption detection subsystem and a signal analysis processing control subsystem, the early warning subsystem comprises a temperature early warning unit, a current voltage-ultrasonic early warning unit and a gas-sound signal early warning unit which are respectively used for monitoring the temperature, the current voltage, the ultrasonic signal, the gas component and the sound signal of the lithium battery in real time; the oxygen consumption detection subsystem comprises an oxygen consumption detection analysis unit and is used for performing thermal runaway heat release statistics, performing data statistics on thermal runaway early warning parameters, finding a thermal runaway heat critical value and making preparations for fire extinguishing; the fire extinguishing subsystem comprises a fire extinguishing unit and is used for quickly starting a fire extinguishing device to extinguish a fire after the thermal runaway of the lithium battery is confirmed; and the signal analysis control subsystem comprises a signal analysis processing control unit and is used for receiving and analyzing the early warning signal and controlling the fire extinguishing subsystem to extinguish fire according to the early warning signal.

Description

Technical Field

[0001] The present invention relates to the field of battery safety technology, and in particular to a lithium battery thermal runaway early warning and fire extinguishing integrated system. Background Art

[0002] When traditional lithium-ion batteries are used or stored, they may short-circuit due to their own internal defects or be subjected to thermal disturbances, impacts, and extrusion, which may lead to thermal runaway, and thermal runaway may cause fire or explosion. At present, there are no targeted fire protection regulations and supervision regulations for lithium-ion batteries, which will inevitably greatly increase the possibility of accidents. Whether it is combustion caused by surrounding combustibles or thermal spontaneous combustion and explosion of lithium-ion batteries themselves, for lithium-ion battery warehouses, once a lithium-ion battery fire occurs, the fire extinguishing equipment equipped in the lithium-ion battery warehouse cannot control the re-ignition of the lithium-ion battery, which will not only cause huge economic losses, but also pose a threat to the lives of personnel. Therefore, research on fire warning and fire extinguishing technology for lithium-ion batteries is of great significance to improving the safety of lithium-ion battery storage.

[0003] At present, the temperature sensor commonly used in lithium battery fire warning systems is non-contact and tests the ambient temperature. However, the ambient temperature changes very little in the early stage of thermal runaway of lithium batteries. When the sensor is activated, the thermal runaway is already uncontrollable. The sensitivity is low and early warning cannot be achieved. At the same time, when the lithium battery is in thermal runaway, the internal materials react violently, releasing a large amount of heat and harmful gases, which can easily cause fires or even explosions. Existing technologies mostly focus on the monitoring of a single parameter and lack a comprehensive and timely early warning and emergency response mechanism. Summary of the invention

[0004] The present invention provides a lithium battery thermal runaway early warning and fire extinguishing integrated system, which solves the problems in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A lithium battery thermal runaway early warning and fire extinguishing integrated system, comprising an early warning subsystem, a fire extinguishing subsystem, an oxygen consumption detection subsystem and a signal analysis and processing control subsystem, wherein the early warning subsystem comprises a temperature early warning unit, a current voltage-ultrasonic early warning unit and a gas-acoustic signal early warning unit, which are respectively used to monitor the temperature, current voltage, ultrasonic signal, gas composition and acoustic signal of the lithium battery in real time;

[0007] The oxygen consumption detection subsystem includes an oxygen consumption detection and analysis unit, which is used to detect oxygen consumption, conduct statistics on heat release due to thermal runaway, conduct data statistics for thermal runaway warning parameters, find the critical value of thermal runaway heat, and prepare for fire extinguishing;

[0008] The fire extinguishing subsystem includes a fire extinguishing unit, which is used to quickly start the fire extinguishing device and extinguish the fire after confirming thermal runaway of the lithium battery; the signal analysis and control subsystem includes a signal analysis and processing control unit, which is used to receive and analyze the early warning signal and control the fire extinguishing subsystem to extinguish the fire according to the early warning signal.

[0009] As a preferred technical solution of the present invention, the temperature warning unit includes a temperature measurement module, the signal output end of the temperature measurement module is connected to the temperature sensing module, the signal output end of the temperature sensing module is connected to the data comparison module, the signal output end of the data comparison module is connected to the signal output module, and the signal output end module is connected to the signal analysis and control subsystem.

[0010] As a preferred technical solution of the present invention, the temperature warning unit is used to monitor the temperature of each module of the lithium battery in real time, and send a fault signal when an abnormal temperature rise is detected in a module. If two or more modules have temperature abnormalities at the same time, a warning signal is sent, and the source of thermal runaway is predicted by comparing the temperature data of each module.

[0011] As a preferred technical solution of the present invention, the current voltage-ultrasonic warning unit includes a voltage detection module, a current detection module and an ultrasonic monitoring SOC status. The signal output ends of the voltage detection module, the current detection module and the ultrasonic monitoring SOC status are connected to a data comparison module, the signal output end of the data comparison module is connected to a signal output module, and the signal output module is connected to a signal analysis and control subsystem.

[0012] As a preferred technical solution of the present invention, the current, voltage and ultrasonic early warning unit monitors the SOC status and health status of the battery in real time through current and voltage monitoring and ultrasonic detection technology, and comprehensively judges the health status of the battery by comparing the ultrasonic data and voltage and current changes under the normal state and overcharge and over-discharge tests, and issues warning and suppression signals in time.

[0013] As a preferred technical solution of the present invention, the gas-acoustic signal warning unit includes a gas detection module and an acoustic signal detection module, the signal output ends of the gas detection module and the acoustic signal detection module are connected to the data analysis module, the signal output end of the data analysis module is connected to the signal output module, and the signal output module is connected to the signal analysis control subsystem.

[0014] As a preferred technical solution of the present invention, the gas detection module is used to monitor the battery deflation and identify characteristic gases, and the acoustic signal detection module is used to establish an acoustic signal resolution model to accurately detect the acoustic signal of battery gas leakage. When abnormalities occur in both gas detection and acoustic signal detection, an early warning signal is sent.

[0015] As a preferred technical solution of the present invention, the oxygen consumption detection and analysis unit includes an oxygen consumption detection module, a signal output end of the oxygen consumption detection module is connected to a thermal analysis module, a signal output end of the thermal analysis module is connected to a data comparison module, a signal output end of the data comparison module is connected to a signal output module, and the signal output module is connected to a signal analysis control subsystem.

[0016] As a preferred technical solution of the present invention, the fire extinguishing unit includes a signal receiving module, a signal output end of the signal receiving module is connected to a signal judging module, and the signal judging module is connected to a signal transmitting module.

[0017] As a preferred technical solution of the present invention, the signal output end of the signal analysis and processing control unit is connected to the signal receiving module of the fire extinguishing unit.

[0018] The present invention has the following benefits: The system can achieve comprehensive monitoring: It realizes multi-dimensional, high-precision early warning of thermal runaway of lithium batteries, and improves the accuracy and timeliness of early warning. Through comprehensive multi-parameter monitoring and analysis, the false alarm rate and missed alarm rate are effectively reduced. The rapid response of the automatic fire extinguishing system effectively curbs the further development of thermal runaway and ensures the safety of the battery system. It improves the overall reliability and safety of the lithium battery system, and provides a strong guarantee for the application in the fields of new energy vehicles, energy storage systems, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is an overall schematic diagram of a lithium battery thermal runaway warning and fire extinguishing integrated system.

[0020] Figure 2 This is an internal schematic diagram of a comprehensive lithium battery thermal runaway warning and fire extinguishing system.

[0021] Figure 3 This is a schematic diagram of the overall unit of a lithium battery thermal runaway warning and fire extinguishing integrated system.

[0022] Figure 4 This is a schematic diagram of a temperature warning unit in a comprehensive lithium battery thermal runaway warning and fire extinguishing system.

[0023] Figure 5 This is a schematic diagram of a current, voltage and ultrasonic warning unit in a comprehensive lithium battery thermal runaway warning and fire extinguishing system.

[0024] Figure 6 This is a schematic diagram of the oxygen consumption detection and analysis unit in a comprehensive lithium battery thermal runaway warning and fire extinguishing system.

[0025] Figure 7 This is a schematic diagram of a gas-acoustic signal warning unit in a comprehensive lithium battery thermal runaway warning and fire extinguishing system.

[0026] Figure 8 This is a schematic diagram of measuring the temperature rise rate in a comprehensive lithium battery thermal runaway warning and fire extinguishing system.

[0027] Fig. 9 The schematic diagram is a framework of a current, voltage and ultrasonic warning unit in a comprehensive lithium battery thermal runaway warning and fire extinguishing system.

[0028] Fig.10 The schematic diagram is a framework of a gas-acoustic signal warning unit in a comprehensive lithium battery thermal runaway warning and fire extinguishing system.

[0029] In the figure: 1. Battery unit; 2. Signal analysis and processing control unit; 3. Current and voltage-ultrasonic warning unit; 4. Temperature warning unit; 5. Gas-acoustic signal warning unit; 6. Oxygen consumption detection and analysis unit; 7. Fire extinguishing unit; 8. Voltage detection module; 9. Current detection module; 10. Ultrasonic monitoring of SOC status; 11. Temperature measurement module; 12. Temperature sensor module; 13. Gas detection module; 14. Acoustic signal detection module; 15. Oxygen consumption detection module; 16. Thermal analysis module. DETAILED DESCRIPTION

[0030] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0031] Example 1, please refer to Figure 1-Figure 10 , a lithium battery thermal runaway early warning and fire extinguishing integrated system, including an early warning subsystem, a fire extinguishing subsystem, an oxygen consumption detection subsystem and a signal analysis and processing control subsystem, the early warning subsystem includes a temperature early warning unit 4, a current voltage-ultrasonic early warning unit 3 and a gas-acoustic signal early warning unit 5, which are respectively used to monitor the temperature, current voltage, ultrasonic signal, gas composition and acoustic signal of the lithium battery in real time;

[0032] The oxygen consumption detection subsystem includes an oxygen consumption detection and analysis unit 6, which is used to detect oxygen consumption, perform statistics on heat release due to thermal runaway, perform data statistics for thermal runaway warning parameters, find the critical value of thermal runaway heat, and prepare for fire extinguishing;

[0033] The fire extinguishing subsystem includes a fire extinguishing unit 7, which is used to quickly start the fire extinguishing device and extinguish the fire after confirming thermal runaway of the lithium battery; the signal analysis and control subsystem includes a signal analysis and processing control unit 2, which is used to receive and analyze the early warning signal and control the fire extinguishing subsystem to extinguish the fire according to the early warning signal.

[0034] When this embodiment is in use, the early warning subsystem, the fire extinguishing subsystem, and the oxygen consumption detection subsystem can jointly monitor the specific parameter changes inside the battery cell 1 in real time, and take corresponding measures in time to protect the battery cell 1 according to the detection data, thereby improving the safety of the battery cell 1, reducing the probability of thermal runaway, discovering signs of thermal runaway in advance, and avoiding fire.

[0035] Example 2, please refer to Figure 1-Figure 10 The temperature warning unit 4 includes a temperature measuring module 11, a signal output end of the temperature measuring module 11 is connected to a temperature sensing module 12, a signal output end of the temperature sensing module 12 is connected to a data comparison module, a signal output end of the data comparison module is connected to a signal output module, and a signal output end module is connected to a signal analysis and control subsystem; wherein the temperature sensing module 12 and the temperature measuring module 11 in the temperature warning unit 4 are fixedly arranged inside the lithium battery cell.

[0036] The temperature warning unit 4 is used to monitor the temperature of each module of the lithium battery in real time. When an abnormal temperature rise is detected in a module, a fault signal is sent. If two or more modules have temperature abnormalities at the same time, a warning signal is sent, and the source of thermal runaway is predicted by comparing the temperature data of each module.

[0037] The temperature warning unit 4 also includes a temperature comparison detection function, which is used to compare the temperature detection data of each module according to the order in which the battery modules are placed, identify the temperature step distribution characteristics, and thus predict the source of thermal runaway.

[0038] The current-voltage-ultrasonic warning unit 3 includes a voltage detection module 8, a current detection module 9 and an ultrasonic monitoring SOC status 10. The signal output ends of the voltage detection module 8, the current detection module 9 and the ultrasonic monitoring SOC status 10 are connected to the data comparison module, the signal output end of the data comparison module is connected to the signal output module, and the signal output module is connected to the signal analysis and control subsystem, wherein one end of the sensor of the voltage detection module 8 and the current detection module 9 are electrically connected to the lithium battery cell for real-time monitoring of the working status of the lithium battery.

[0039] The current-voltage-ultrasonic warning unit 3 monitors the SOC state and health status of the battery in real time through current-voltage monitoring and ultrasonic detection technology, and comprehensively judges the health status of the battery by comparing the ultrasonic data and voltage and current changes under the normal state and the overcharge and over-discharge test, and issues warning and suppression signals in time.

[0040] Combine current and voltage monitoring with ultrasonic detection technology to monitor the battery SOC status and health status in real time. By comparing the ultrasonic data under normal state and overcharge and over-discharge test, combined with voltage and current changes, the battery health status can be comprehensively judged, and warning and suppression signals can be issued in time.

[0041] The gas-acoustic signal warning unit 5 includes a gas detection module 13 and an acoustic signal detection module 14. The signal output ends of the gas detection module 13 and the acoustic signal detection module 14 are connected to the data analysis module. The signal output end of the data analysis module is connected to the signal output module. The signal output module is connected to the signal analysis control subsystem. The gas detection module 13 and the acoustic signal detection module 14 are arranged on one side of the lithium battery cell.

[0042] The gas detection module 13 is used to monitor the battery deflation and identify characteristic gases. The acoustic signal detection module 14 is used to establish an acoustic signal resolution model to accurately detect the acoustic signal of battery gas leakage. When both gas detection and acoustic signal detection are abnormal, an early warning signal is sent.

[0043] The gas-acoustic signal warning unit 5 is used to monitor the battery deflation, and the built-in gas analysis device identifies characteristic gases such as HF. At the same time, the gas-acoustic signal warning unit 5 detects the acoustic signal, establishes an acoustic signal discrimination model, and combines the gas detection signal to accurately determine the battery gas leakage, thereby achieving double warning.

[0044] The actual operation situation is that when the battery thermally runs away, the safety valve will be opened by the gas generated by the internal reaction, and these gases are basically generated by the electrolyte reaction inside the battery. When the battery thermally runs away, there is a large amount of HF gas regardless of whether there is fire or not. The gas detection module 13 can effectively detect the degassing of the battery, but due to the influence of the environment, it may cause the air flow around the battery module and make it impossible to distinguish the source of the airflow. Therefore, a gas analysis device needs to be added to the gas detection module 13 to monitor the components in the airflow when gas is generated, and issue an early warning to the system when HF gas is detected. Before the battery thermal runaway causes a fire or explosion, the sound of leakage and explosion can be heard. The sound of leakage is caused by the leakage of gas inside the battery. Therefore, ventilation sound signal detection is set at the same time as the gas detection, and an acoustic signal resolution model is set to remove the influence of other noises that already exist around the battery module, so that the acoustic signal of battery gas leakage can be accurately detected.

[0045] The oxygen consumption detection and analysis unit 6 includes an oxygen consumption detection module 15, a signal output end of the oxygen consumption detection module 15 is connected to a heat analysis module 16, a signal output end of the heat analysis module 16 is connected to a data comparison module, a signal output end of the data comparison module is connected to a signal output module, and the signal output module is connected to a signal analysis control subsystem.

[0046] The heat release statistics of thermal runaway are carried out through oxygen consumption, and data statistics are carried out for thermal runaway warning parameters to find the critical value of thermal runaway heat and prepare for fire extinguishing. The theoretical calculation formula is as follows: Where q is HRR (kW), heat release rate, and are the flow rates of oxygen in the intake and outlet air ((Kg·s-1), E is the energy release per mass unit O_2 of a given fuel consumption ((); mass flow rate ()) The calculation formula is shown in formula (4), where A is the cross-sectional area (m2), kc is the wind speed distribution coefficient, f(Re) is the Reynolds number correction function, △P is the centerline pressure difference of the Pitot tube (Pa), T is the centerline temperature of the duct (K), and q is calculated by the changes in,, and, because it is actually incomplete combustion. Where and are the initial and final oxygen volume percentage concentrations (%), and are the initial and final carbon dioxide volume percentage concentrations (%), and is the final CO volume percentage concentration (%). Q is THR (kJ).

[0047]

[0048]

[0049] The fire extinguishing unit 7 comprises a signal receiving module, a signal output end of the signal receiving module is connected to a signal judging module, and the signal judging module is connected to a signal transmitting module.

[0050] The signal output end of the signal analysis and processing control unit 2 is connected to the signal receiving module of the fire extinguishing unit 7 .

[0051] Example 3, please refer to Figure 1-Figure 10 The actual application scenario of this embodiment is to conduct real-time monitoring based on multiple parameters to improve the accuracy of early warning; accurate early warning can detect signs of thermal runaway in advance through multi-source data fusion analysis to avoid fire, and can automatically respond once thermal runaway is confirmed to automatically start the fire extinguishing system to reduce casualties and property losses; and provide a scientific basis for fire extinguishing strategies through data-supported oxygen consumption statistics to optimize fire extinguishing effects.

[0052] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A lithium battery thermal runaway early warning and fire extinguishing integrated system, comprising an early warning subsystem, a fire extinguishing subsystem, an oxygen consumption detection subsystem and a signal analysis and processing control subsystem, characterized in that: The early warning subsystem comprises a temperature early warning unit (4), a current voltage-ultrasonic early warning unit (3) and a gas-acoustic signal early warning unit (5), which are respectively used to monitor the temperature, current voltage, ultrasonic signal, gas composition and acoustic signal of the lithium battery in real time; The oxygen consumption detection subsystem includes an oxygen consumption detection and analysis unit (6) for detecting oxygen consumption, performing statistics on heat release due to thermal runaway, performing data statistics for thermal runaway warning parameters, finding a critical value of heat due to thermal runaway, and preparing for fire extinguishing; The fire extinguishing subsystem comprises a fire extinguishing unit (7) for rapidly starting the fire extinguishing device to extinguish the fire after confirming that the lithium battery is in thermal runaway; the signal analysis and control subsystem comprises a signal analysis and processing control unit (2) for receiving and analyzing the early warning signal and controlling the fire extinguishing subsystem to extinguish the fire according to the early warning signal.

2. A lithium battery thermal runaway early warning and fire extinguishing integrated system according to claim 1, characterized in that: The temperature warning unit (4) comprises a temperature measuring module (11), the signal output end of the temperature measuring module (11) is connected to the temperature sensing module (12), the signal output end of the temperature sensing module (12) is connected to the data comparison module, the signal output end of the data comparison module is connected to the signal output module, and the signal output end module is connected to the signal analysis control subsystem.

3. A lithium battery thermal runaway early warning and fire extinguishing integrated system according to claim 2, characterized in that: The temperature warning unit (4) is used to monitor the temperature of each module of the lithium battery in real time, and sends a fault signal when an abnormal temperature rise of a module is detected. If two or more modules have temperature abnormalities at the same time, a warning signal is sent, and the source of thermal runaway is predicted by comparing the temperature data of each module.

4. A lithium battery thermal runaway early warning and fire extinguishing integrated system according to claim 1, characterized in that: The current voltage-ultrasonic warning unit (3) comprises a voltage detection module (8), a current detection module (9) and an ultrasonic monitoring SOC state (10); the signal output ends of the voltage detection module (8), the current detection module (9) and the ultrasonic monitoring SOC state (10) are connected to a data comparison module; the signal output end of the data comparison module is connected to a signal output module; and the signal output module is connected to a signal analysis and control subsystem.

5. A lithium battery thermal runaway early warning and fire extinguishing integrated system according to claim 4, characterized in that: The current voltage-ultrasonic warning unit (3) monitors the SOC state and health status of the battery in real time through current voltage monitoring and ultrasonic detection technology, and comprehensively judges the health status of the battery by comparing ultrasonic data and voltage and current changes under normal conditions and overcharge and overdischarge tests, and issues warning and suppression signals in a timely manner.

6. A lithium battery thermal runaway early warning and fire extinguishing integrated system according to claim 1, characterized in that: The gas-acoustic signal warning unit (5) comprises a gas detection module (13) and an acoustic signal detection module (14), the signal output ends of the gas detection module (13) and the acoustic signal detection module (14) are connected to a data analysis module, the signal output end of the data analysis module is connected to a signal output module, and the signal output module is connected to a signal analysis control subsystem.

7. A lithium battery thermal runaway early warning and fire extinguishing integrated system according to claim 6, characterized in that: The gas detection module (13) is used to monitor the battery gas discharge and identify characteristic gases, and the acoustic signal detection module (14) is used to establish an acoustic signal resolution model to accurately detect the acoustic signal of battery gas leakage, and to send an early warning signal when both gas detection and acoustic signal detection are abnormal.

8. A lithium battery thermal runaway early warning and fire extinguishing integrated system according to claim 1, characterized in that: The oxygen consumption detection and analysis unit (6) comprises an oxygen consumption detection module (15), a signal output end of the oxygen consumption detection module (15) is connected to a heat analysis module (16), a signal output end of the heat analysis module (16) is connected to a data comparison module, a signal output end of the data comparison module is connected to a signal output module, and the signal output module is connected to a signal analysis control subsystem.

9. A lithium battery thermal runaway early warning and fire extinguishing integrated system according to claim 1, characterized in that: The fire extinguishing unit (7) comprises a signal receiving module, a signal output end of the signal receiving module is connected to a signal judging module, and the signal judging module is connected to a signal transmitting module.

10. A lithium battery thermal runaway early warning and fire extinguishing integrated system according to claim 9, characterized in that: The signal output end of the signal analysis and processing control unit (2) is connected to the signal receiving module of the fire extinguishing unit (7).

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