WO2020019578A1 - Battery fire early-warning system and method - Google Patents

Abstract

A battery fire early-warning system (100), comprising a battery module housing (10), at least one first detection device (20), at least one second detection device (30), at least one third detection device (40), a plurality of fourth detection devices (50), and a battery management system (60). A plurality of battery cells (101) is provided in the battery module housing (10), and each of the battery cells (101) is provided with a safety valve (102). The first detection device (20) is disposed on the inner wall of the battery module housing (10), and the first detection device (20) is arranged opposite a plurality of safety valves (102). The second detection device (30) is disposed on the inner wall of the battery module housing (10), and the second detection device (30) is arranged opposite the plurality of safety valves (102). The third detection device (40) is disposed on the inner wall of the battery module housing (10), and the third detection device (40) is arranged opposite the plurality of safety valves (102). Each of the fourth detection devices (50) is disposed on the surface of each of the battery cells (101). The battery fire early-warning system (100) can implement early warning of a fire of batteries from multiple perspectives such as images, gas, sound, and temperature, thereby avoiding false alarm or missing alarm of the fire.

Description

Battery fire early warning system and method

Related applications

This application requires application on July 27, 2018, with the application number 201810840864.2, entitled "Battery Fire Early Warning System and Method" and application on July 27, 2018, with the application number 201810840708.6, entitled "Battery Fire Early Warning System and Method "and the priority of the Chinese patent application filed on July 27, 2018, with application number 201810840443.X, entitled" Battery Fire Early Warning System and Method ", which is incorporated herein by reference in its entirety.

Technical field

The present application relates to the field of lithium ion battery safety, and in particular, to a battery fire early warning system and method.

Background technique

In recent years, the market share of electric vehicles has steadily increased. Lithium-ion batteries have excellent performance such as high voltage, high specific energy, long cycle life, and no pollution to the environment. They have attracted great attention from the electric vehicle industry, and have gained certain applications. However, during the thermal runaway process of lithium-ion batteries, combustible gas mixtures such as H ₂ , CO, and CH ₄ are generated and accumulated inside the battery. After the battery reaches a certain pressure limit, the safety valve opens, and the combustible mixture is released into the external environment as the battery erupts.

Because the high temperature surface of the battery and the temperature of Mars are much higher than the ignition temperature of the gaseous eruption, once the eruption is sprayed into the air and contacts with oxygen, it will be very easy to catch fire and cause a fire. After the battery erupts, high-temperature combustibles are also prone to spontaneous combustion after coming into contact with the air entering the battery. In addition, even if the gaseous eruption does not catch fire after the battery erupts, if it gradually accumulates to a certain amount, an explosion may occur and its harm will be greater. Current lithium ion battery fire early warning methods and systems have a single detection mode for lithium ion battery fire early warning, and cannot comprehensively warn lithium ion battery fires from multiple perspectives, leading to false or false alarms. There are security risks.

Application content

In view of this, the present application discloses a battery fire early warning system and method that can realize battery fire early warning from multiple perspectives.

The present application discloses a battery fire early warning system, which includes a battery module case, at least one first detection device, at least one second detection device, at least one third detection device, a plurality of fourth detection devices, and a battery management system. A plurality of battery cells are disposed in the battery module case, and each of the battery cells is provided with a safety valve. The first detection device is disposed on the inner wall of the battery module housing, and the first detection device is disposed opposite to the plurality of safety valves, and is disposed to detect when the battery cell is about to release or has undergone thermal runaway. Out of the electrolyte or soot particles. The second detection device is disposed on the inner wall of the battery module housing, and the second detection device is disposed opposite to the plurality of safety valves, and is disposed to detect that the plurality of battery cells are about to undergo or have thermal runaway. When the shape changes. The third detection device is disposed on the inner wall of the battery module case, and the third detection device is disposed opposite to the plurality of safety valves, and is disposed to collect that the plurality of battery cells is about to have or has undergone thermal runaway. Sound waves produced by air jets during the eruption process. Each of the fourth detection devices is disposed on the surface of each of the battery cells or between the two battery cells, and is configured to detect the temperature of the surface of the battery cells when the plurality of battery cells are about to undergo or thermal runaway, Changes in surface strain or squeezing force between two battery cells. The first detection device is connected to the battery management system, the second detection device is connected to the battery management system, the third detection device is connected to the battery management system, and the plurality of fourth detection devices Connected to the battery management system.

In one embodiment, the first detection device is a smoke sensor or a gas sensor.

In one embodiment, the second detection device is a photographing device.

In one embodiment, the third detection device is a sound collection device.

In one embodiment, the fourth detection device is a temperature sensor.

In one embodiment, the battery management system includes a control unit, a first detection unit, a second detection unit, a third detection unit, and a fourth detection unit. An input terminal of the first detection unit is connected to the first detection device, and an output terminal of the first detection unit is connected to the control unit. An input terminal of the second detection unit is connected to the second detection device, and an output terminal of the second detection unit is connected to the control unit. An input terminal of the third detection unit is connected to the third detection device, and an output terminal of the third detection unit is connected to the control unit. An input terminal of the fourth detection unit is connected to the plurality of fourth detection devices, and an output terminal of the fourth detection unit is connected to the control unit.

In one embodiment, the battery management system further includes a fire extinguishing device, and the fire extinguishing device is connected to the control unit.

In one embodiment, the second detection device includes a plurality of cameras. The plurality of cameras are disposed on an inner wall of the battery module housing, and each of the cameras is connected to the battery management system.

In one embodiment, each of the cameras is disposed on a geometric center of each inner wall surface of the battery module housing, and is configured to accurately position the plurality of battery cells.

In one embodiment, each of the cameras is connected to an input terminal of the second detection unit, and an output terminal of the second detection unit is connected to the control unit.

In one embodiment, the plurality of cameras are infrared cameras.

In one embodiment, the battery fire early warning system further includes a spectrum analysis device. An input end of the spectrum analysis device is connected to the third detection device, and an output end of the spectrum analysis device is connected to the third detection unit.

In one embodiment, the third detection device includes a plurality of noise sensors, the plurality of noise sensors are disposed on an inner wall of the battery module housing, and each of the noise sensors and the spectrum analysis device Connected to the input.

In one embodiment, each of the noise sensors is disposed at a geometric center of each inner wall surface of the battery module case.

In one embodiment, each of the safety valves is disposed at an air outlet of each of the battery cells, and a plurality of the safety valves are opposite to a top surface of an inner wall of the battery module case.

In one embodiment, the noise sensor is disposed on a side surface of an inner wall of the battery module case, and is disposed near a top surface of the inner wall.

In one embodiment, the noise sensor is disposed on the surface of each of the battery cells and is disposed near the safety valve.

In one embodiment, a battery fire early warning method includes: obtaining first signal parameters of a plurality of battery cells in a battery module housing according to a second detection device and a fourth sensing device; and according to the first Signal parameter, the control unit sends a warning signal; when the control unit sends a warning signal, according to the second detection device and the third detection device, obtain the number of the plurality of battery cells in the battery module housing A second signal parameter; according to the second signal parameter, the control unit sends out a fire warning signal; when the control unit sends out a fire warning signal, according to a first detection device, the plurality of cells in the battery module housing are obtained A third signal parameter of each battery cell; and according to the third signal parameter, the control unit escapes a signal.

In one embodiment, in the step of obtaining the first signal parameters of a plurality of battery cells in the battery module housing according to the second detection device and the fourth sensing device, the first signal parameters are the multiple The first image characteristic parameter of each battery cell and the surface temperature parameter of the plurality of battery cells.

In one embodiment, when the control unit issues a warning signal, according to the second detection device and the third detection device, a second signal of the plurality of battery cells in the battery module housing is obtained. In the parameter step, the second signal parameter is a second image characteristic parameter of the plurality of battery cells and a frequency characteristic and an amplitude characteristic of a sound wave.

The application provides the battery fire early warning system. The first detection device is used to detect an electrolyte solution or soot particles released when the battery cell is thermally out of control. The second detection device is used to detect a change in shape of the plurality of battery cells when thermal runaway is about to occur or has occurred. The third detection device is configured to detect a vibration frequency of noise caused by airflow ejection during a battery eruption process when the plurality of battery cells is about to undergo thermal runaway. Each of the fourth detection devices is configured to detect a change in a temperature or a surface strain force on a surface of each of the battery cells or a pressing force between two adjacent battery cells. At the same time, the first detection device, the second detection device, the third detection device, and the fourth detection device transmit signals collected when the plurality of battery cells are about to or have thermal runaway. The battery management system. Thus, the battery management system issues a fire warning signal or activates a fire warning device.

The first detection device, the second detection device, the third detection device, and the fourth detection device are different types of detectors, and can be used for detecting the imminent or thermal runaway from different aspects. The plurality of battery cells in the battery module case are detected. The battery fire early warning system can realize battery fire early warning from multiple angles, such as image, gas, sound, temperature, squeezing force, etc., avoiding false or false alarms of the fire, and improving the safety of the battery in fire early warning To avoid loss of life and property.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to explain the technical solutions in the embodiments of the present application or the prior art more clearly, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely It is an embodiment of the present application. For those of ordinary skill in the art, other drawings can be obtained according to the disclosed drawings without paying creative labor.

FIG. 1 is a schematic structural diagram of a battery fire early warning system provided by the present application;

2 is a schematic diagram of a camera installation of a battery fire early warning system structure provided by the present application;

FIG. 3 is a schematic diagram of a specific structure of a camera of a battery fire early warning system structure provided by the present application; FIG.

4 is a schematic diagram of a camera installation structure in an embodiment of a battery fire early warning system structure provided by the present application;

FIG. 5 is a schematic plan view of a mounting structure of a camera in an embodiment of a battery fire early warning system structure provided by the present application; FIG.

6 is a schematic structural side view of a camera mounting structure in an embodiment of a battery fire early warning system structure provided by the present application;

7 is a top structural schematic view of a mounting structure of a camera in an embodiment of a battery fire early warning system structure provided by the present application;

FIG. 8 is a schematic diagram of installing a noise sensor of a battery fire early warning system structure provided by the present application; FIG.

FIG. 9 is a detailed structural diagram of a noise sensor of a battery fire early warning system structure provided by the present application; FIG.

10 is a schematic side view of a mounting structure of a noise sensor in an embodiment of a battery fire early warning system structure provided by the present application;

FIG. 11 is a schematic diagram of an installation structure of a noise sensor in an embodiment of a battery fire early warning system structure provided by the present application; FIG.

FIG. 12 is a schematic diagram of an installation structure of a noise sensor in an embodiment of a battery fire early warning system structure provided by the present application; FIG.

13 is a schematic plan view of a mounting structure of a noise sensor in an embodiment of a battery fire early warning system structure provided by the present application;

14 is a schematic structural side view of a mounting structure of a noise sensor in an embodiment of a battery fire early warning system structure provided by the present application;

FIG. 15 is a schematic plan view of a mounting structure of a noise sensor in an embodiment of a battery fire early warning system structure provided by the present application.

detailed description

In the following, the technical solutions in the embodiments of the present application will be clearly and completely described with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

In order to make the purpose, technical solution, and advantages of the present application clearer, the following further describes the present application in detail with reference to the embodiments and the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the application, and are not used to limit the application.

Referring to FIG. 1, the present application discloses a battery fire warning system 100 including a battery module case 10, at least one first detection device 20, at least one second detection device 30, at least one third detection device 40, and a plurality of Fourth detection 50 and battery management system 60. A plurality of battery cells 101 are disposed in the battery module case 10, and each of the battery cells 101 is provided with a safety valve 102. The first detection device 20 is disposed on an inner wall of the battery module case 10, and the first detection device 20 is disposed opposite to a plurality of the safety valves 102. The second detection device 30 is disposed on the battery. The second detection device 30 is disposed opposite to the plurality of safety valves 102 on the inner wall of the module case 10, the third detection device 40 is disposed on the inner wall of the battery module case 10, and the third A detection device 40 is disposed opposite to the plurality of safety valves 102, and each of the fourth detection devices 50 is disposed on a surface of each of the battery cells 101. The first detection device 20 is connected to the battery management system 60, the second detection device 30 is connected to the battery management system 60, and the third detection device 40 is connected to the battery management system 60. A plurality of fourth detection devices 50 are connected to the battery management system 60.

The first detection device 20 is used to detect an electrolyte solution or soot particles released when the battery cell 101 is thermally out of control. The second detection device 30 is configured to detect a change in shape of the plurality of battery cells 101 when the battery cells 101 are about to undergo thermal runaway. The third detecting device 40 is configured to detect a vibration frequency of noise caused by airflow ejection during a battery erupting process when the plurality of battery cells 101 is about to undergo thermal runaway. Each of the fourth detection devices 50 is configured to detect a temperature of a surface of each of the battery cells 101 or a pressure change between two adjacent battery cells 101. At the same time, the plurality of battery cells 101 that will be collected by the first detection device 20, the second detection device 30, the third detection device 40, and the fourth detection device 50 are about to or have thermal runaway. The time signal is transmitted to the battery management system 60. Therefore, the battery management system 60 issues a fire warning signal or activates a fire warning device.

The first detection device 20, the second detection device 30, the third detection device 40, and the fourth detection device 50 are different types of detectors, which can control thermal imminence or imminent thermal runaway from different aspects. The plurality of battery cells 101 in the battery module case 10 are detected at this time. The battery fire early warning system 100 can realize battery fire early warning from multiple angles such as image, gas, sound, temperature, squeeze force, etc., avoiding false or false alarms of the fire, and improving the safety of the battery in fire early warning. Sex, to avoid the loss of life and property. In order to improve the utilization rate of the battery, the battery management system 60 (BATTERY MANAGEMENT SYSTEM, BMS) can prevent the battery from being overcharged and overdischarged. The battery management system has an accurate estimation of the state of charge of the power battery pack, dynamic monitoring and balance between the batteries.

During the battery charging and discharging process, the terminal voltage and temperature, the charging and discharging current, and the total battery pack voltage of each of the battery cells 101 in the battery pack of the electric vehicle are collected in real time to prevent the battery from overcharging or overdischarging. At the same time, the status of each of the battery cells 101 can be given in time, and the battery in question can be selected to maintain the reliability and efficiency of the entire battery operation, making it possible to implement the remaining power estimation model.

In one embodiment, the number of the first detection device 20, the second detection device 30, the third detection device 40, and the fourth detection device 50 is not limited, and may be one or more . In addition, the installation positions of the first detection device 20, the second detection device 30, the third detection device 40, and the fourth detection device 50 may also be placed on the inner wall of the battery module case 10. Other locations can be easily detected.

In one embodiment, the first detection device 20 is a smoke sensor or a gas sensor. The first detection device 20 may be an ionic smoke sensor, a photoelectric smoke sensor, a gas-sensitive smoke sensor, or the like.

When one or more of the battery cells 101 in the battery module case 10 are about to or have thermal runaway, eruptions accumulate inside the battery cells 101 to a certain pressure and exceed the hard shell, the When the pressure limit value of the safety valve 102 or the soft case of the battery cell 101 is emitted, the battery cell 101 will erupt to the outside of the battery cell 101. At this time, the first detection device 20 is a smoke sensor. The first detection device 20 realizes fire prevention by monitoring the smoke concentration, and is widely used in various fire alarm systems, and its performance is far better than that of gas thermistor type fire alarms. The first detection device 20 is mainly used to collect the electrolytic solution or soot particles released from the battery cell 101. The first detection device 20 is connected to the battery management system 60. When the first detection device 20 detects the electrolyte or soot particles released by the battery cell 101, it will collect the collected information about the The signal of the eruption when the battery cell 101 is about to undergo thermal runaway has been transmitted to the battery management system 60. Therefore, the battery management system 60 issues a fire warning signal.

In one embodiment, the first detection device 20 is a smoke meter.

In one embodiment, the first detection device 20 is placed directly above the safety valve 102 of the plurality of battery cells 101, or at a battery module case 10, or at a vent of a battery pack case. One or more of the first detection devices 20 may be placed in the process according to actual needs. When the first detection device 20 collects the composition of the electrolyte, soot particles, H ₂ , CO, and CH ₄ mixed flue gas released from the battery cell 101, it is transmitted to the battery management system 60. Then, the battery management system 60 issues a fire warning signal.

In one embodiment, the second detection device 30 is a photographing device. When the shape of one or more of the battery cells 101 changes, such as swelling, safety valve opening, rupture, etc., due to different abuse methods such as thermal abuse, mechanical abuse, and electrical abuse, the second detection device 30 may pass a photographing device. An image of the shape of one or more of the battery cells 101 in the battery module case 10 is acquired. A picture is taken by the second detection device 30, and the picture information is transmitted to the battery management system 60. The second detection device 30 only needs to cover a range where the safety valves 102 of all the battery cells 101 in one of the battery module cases 10 are located.

In one embodiment, one or more infrared camera lenses can be placed in the battery module housing 10. Since the battery module case 10 is sealed inside and the light is insufficient, an infrared camera can be used.

In one embodiment, the position of the second detection device 30 may be directly above the safety valves of the plurality of battery cells 101. Alternatively, each of the second detection devices 30 may correspond to one of the battery cells 101. The battery management system 60 performs further recognition processing based on the grayscale difference of the picture taken by the battery management system 60, and compares the shape with the normal shape of the battery cell 101. If the shape changes, the battery management The system 60 issues a fire warning signal.

In one embodiment, the third detection device 40 is a sound collection device. When one or more of the battery cells 101 in the battery module case 10 are thermally out of control, one or more of the battery cells 101 may emit particulate matter or a gas mixture. During the eruption of the battery cell 101, the friction between the air flow and the outlet, the surrounding air, etc. causes vibration to generate noise, which is accompanied by a unique frequency, and the frequency is closely related to the spray speed of the air flow. Therefore, the unique vibration frequency caused by the eruption can be collected by the sound collection device, and it can be determined whether the spray phenomenon of the battery cell 101 occurs, and the related parameters of the vibration frequency are transmitted to the battery management system 60, so that The battery management system 60 issues a fire warning signal.

During the eruption of the battery, the airflow rubs and collides with the wall surface at the exit and the surrounding air to cause vibration, which in turn causes air to vibrate and emit sound. Among them, the generated sound is closely related to the jet pressure, jet speed, nozzle shape, box structure, etc. of the airflow, and has unique characteristics that distinguish it from other voices. The sound collection device is used to collect sound waves emitted during the eruption of the battery cell 101, and transmit the sound wave signals to the battery management system 60. Therefore, the battery management system 60 performs a Fourier transform on the collected sound waves, and performs steps such as filtering and removing noise data to separate or demodulate complex signals into sine waves with different frequencies and amplitudes, and obtain the sound waves. Frequency and amplitude characteristics. The battery management system 60 compares the frequency characteristics and amplitude characteristics of the collected acoustic waves with the frequency characteristics and amplitude characteristics of the target acoustic waves. If the frequency and amplitude of the collected sound wave appear to be the frequency distribution and amplitude distribution of the target sound wave, it can be considered that the spraying phenomenon of the battery cell 101 occurs, and the battery management system 60 issues a fire alarm at this time.

In one embodiment, the number of the third detection device 40 may be one or more, and the third detection device 40 may be disposed above the safety valve 102 of the plurality of battery cells 101. .

In one embodiment, the fourth detection device 50 is a temperature sensor. When one or more of the battery cells 101 in the battery module housing 10 are about to occur or thermal runaway has occurred, the temperature of the surface of the battery cells 101 will rise sharply, often accompanied by the battery The expansion of the shell of the monomer 101. The fourth detection device 50 can identify the surface temperature of the battery cell 101. The signal data collected by the fourth detection device 50 is transmitted to the battery management system 60, and the battery management system 60 is further used to determine the thermal runaway state of the battery.

In one embodiment, the fourth detection device 50 is a strain sensor. When one or more of the battery cells 101 in the battery module housing 10 are about to occur or thermal runaway has occurred, the battery cells 101 are often accompanied by a shell expansion phenomenon. At this time, a strain sensor can be used. A change in the surface stress of the battery cell 101 is detected. The signal data collected by the fourth detection device 50 is transmitted to the battery management system 60, and the battery management system 60 is further used to determine the thermal runaway state of the battery.

In one embodiment, the fourth detection device 50 is a squeeze force sensor. When one or more of the battery cells 101 in the battery module housing 10 are about to occur or thermal runaway has occurred, the battery cells 101 are often accompanied by a shell expansion phenomenon. At this time, a touch sensor may be used. Changes in the compression stress between two adjacent battery cells 101 are detected. The signal data collected by the fourth detection device 50 is transmitted to the battery management system 60, and then a fire warning signal is issued by the battery management system 60.

In one embodiment, the battery management system 60 includes a control unit 610, a first detection unit 620, a second detection unit 630, a third detection unit 640, and a fourth detection unit 650. An input terminal of the first detection unit 620 is connected to the first detection device 20, and an output terminal of the first detection unit 620 is connected to the control unit 610. An input terminal of the second detection unit 630 is connected to the second detection device 30, and an output terminal of the second detection unit 630 is connected to the control unit 610. An input terminal of the third detection unit 640 is connected to the third detection device 40, and an output terminal of the third detection unit 640 is connected to the control unit 610. An input terminal of the fourth detection unit 650 is connected to the plurality of fourth detection devices 50, and an output terminal of the fourth detection unit 650 is connected to the control unit 610.

The battery module case 10 contains a large number or even thousands of the battery cells 101. An input terminal of the first detection unit 620 is connected to the first detection device 20, and an output terminal of the first detection unit 620 is connected to the control unit 610. The first detection device 20 can detect the spray phenomenon appearing on the battery cell 101, collect the concentration of the electrolyte or soot particles released by the battery cell 101, and transmit the signal information to the first A detection unit 620, the first detection unit 620 analyzes a smoke signal released by the battery cell 101, and sends a fire warning signal through the control unit 610.

An input terminal of the second detection unit 630 is connected to the second detection device 30, and an output terminal of the second detection unit 630 is connected to the control unit 610. The second detection device 30 can quickly, accurately and comprehensively capture the image change of each of the battery cells 101. The second detection device 30 uses an industrial camera to take a picture, and then the second detection unit 630 uses software to identify useful information after processing according to the grayscale difference of the picture. The second detection unit 630 performs image analysis on the image of the battery cell 101 captured by the second detection device 30 and compares the image with the normal battery cell 101. The second detection unit 630 transmits an image analysis result to the control unit 610. When a shape of one or more of the battery cells 101 changes, the control unit 610 issues a fire warning signal.

An input terminal of the third detection unit 640 is connected to the third detection device 40, and an output terminal of the third detection unit 640 is connected to the control unit 610. The third detection device 40 is based on a specific vibration frequency occurring during the eruption of the battery cell 101. The third detection unit 640 generates a sound by directly vibrating the airflow collected by the third detection device 40 with the outlet, the surrounding air, and the like to generate a sound, and the sound is analyzed with a unique frequency. When one or more of the battery cells 101 are out of control, the control unit 610 sends out a fire warning signal.

An input terminal of the fourth detection unit 650 is connected to the plurality of fourth detection devices 50, and an output terminal of the fourth detection unit 650 is connected to the control unit 610. Each of the fourth detection devices 50 may detect a temperature on a surface of each of the battery cells 101, or the fourth detection device 50 disposed between the adjacent fourth detection devices 50 may detect two adjacent cells. The pressure change between the battery cells 101 due to thermal runaway. When thermal runaway occurs in one or more of the battery cells 101, the signal information collected by the plurality of fourth detection devices 50 is transmitted to the fourth detection unit 650, and the control unit 610 issues a fire warning signal.

At least one of the first detection device 20, at least one of the second detection device 30, at least one of the third detection device 40, and the plurality of fourth detection devices 50 can be used to test the battery module from multiple angles. The plurality of battery cells 101 in the pack case 10 are monitored in real time, avoiding false alarms or false alarms caused by using a single detector, and improving the safety of the battery fire early warning system 100, and The cost of the battery fire early warning system 100 is reduced.

In one embodiment, the battery fire early warning system 100 further includes a fire extinguishing device 70. The fire extinguishing device 70 is connected to the control unit 610.

In one embodiment, when one or more of the battery cells 101 are about to undergo or have thermal runaway, the first detection unit 620, the second detection unit 630, the third detection unit 640, and The fourth detection unit 650 collects analysis signal information, and transmits the analysis result to the control unit 610, and the control unit 610 sends out a fire warning signal. When the fire extinguishing device 70 is connected to the control unit 610, the control unit 610 sends out a fire warning signal to control the fire extinguishing device 70 to extinguish fire. In the driving situation, the control unit 610 alerts the car, and the car can control power failure. At this time, the battery cell 101 will not have a current output, and the danger can be controlled in time. During the charging process, the control unit 610 presents a fire alarm signal to the charger, at which time the charger stops charging, and the battery management system 60 itself can also cut off the current.

In one embodiment, the control unit 610 sends out a fire early warning signal, which can remind the driver, the driver can extinguish the fire manually, or the control unit 610 can send out a fire early warning signal, so that the driver and passengers can quickly leave the car.

The second detector device 30 is a photographing device and can obtain image information of the plurality of battery cells 101. At the same time, the shape, size, position, characteristics and mutual relationship of the plurality of battery cells 101 can be obtained by processing the pictures obtained by the optical camera, and one or more of the batteries that are about to undergo or have thermal runaway can be located in time Monomer 101. Capturing images of changes in the plurality of battery cells 101 through the photographing device 20, such as one or more of the battery cells 101 expanding, a safety valve being opened, an outer packaging film ruptured, the battery cells 101 erupting, etc. phenomenon.

The second detection unit 630 is connected to the photographing device, and recognizes changes in one or more of the battery cells 101 through image preprocessing, image segmentation, feature value extraction, and the like. The image information of the battery cell 101 is converted into a digital signal. The photographing device can quickly and accurately identify whether a spray phenomenon occurs on the battery. At this time, the battery management system 60 judges whether to issue based on the relationship between the digital signals that characterize the battery expansion, safety valve opening, outer packaging rupture, battery eruption and other phenomena such as thermal runaway and fire in the battery cell 101. Early warning signs of fire. The battery management system 60 sends out an early warning signal for fire, so that the driver or the fire extinguishing device of the car can make corresponding rescue measures to improve the safety during the use of the battery.

Referring to FIGS. 2-3, in an embodiment, the second detection device 30 includes a plurality of cameras 310. The plurality of cameras 310 are disposed on an inner wall of the battery module housing 10, and each of the cameras 310 is connected to the battery management system 60.

In order to improve the utilization rate of the battery, the battery management system 60 prevents the battery from being overcharged and overdischarged. The battery management system has an accurate estimation of the state of charge of the power battery pack, dynamic monitoring and balance between the batteries. During the battery charging and discharging process, the terminal voltage and temperature of each battery in the electric vehicle battery pack, the charging and discharging current, and the total voltage of the battery pack are collected in real time to prevent the battery from overcharging or overdischarging. At the same time, the status of the battery can be given in time, and the battery in question can be selected to maintain the reliability and efficiency of the entire battery operation, making it possible to implement the remaining power estimation model.

In one embodiment, each of the cameras 310 is disposed on a geometric center of each inner wall surface of the battery module case 10, and is configured to accurately position the plurality of battery cells 101. The shape of the battery module case 10 is not limited, and may be a rectangular parallelepiped, a cube, a cylinder, or the like. Each camera 310 is disposed at a geometric center of each inner wall surface of the battery module case 10 The image obtained by the optical camera is processed to obtain the shape, size, position, characteristics, and their relationship of the plurality of battery cells 101 photographed. Each of the cameras 310 is disposed on a diagonal line of each inner wall surface of the battery module housing 10, and can be positioned from all directions to fully capture the safety of one or more of the battery cells 101 The changes in the valve 102 and the battery body are compared with normal battery cells, and one or more of the battery cells 101 that have changed can be clearly observed.

Each of the cameras 310 is disposed on a geometric center of each inner wall surface of the battery module casing 10, and the geometric positioning determines the size, shape, and spatial position of the subject. In the positioning process, the three-dimensional coordinates of the to-be-determined ground points constituting the two photographic rays can be met according to two known photographic sites and two known photographic direction lines. When processing the acquired images of the plurality of battery cells 101, V-STARS software can be used to process the acquired pictures to obtain the three-dimensional coordinates of the points to be measured. The precise three-dimensional coordinates of the point to be measured are obtained by performing image matching and other related mathematical calculations at different positions and directions. The battery management system 30 can also output the three-dimensional data of the position, and at the same time, a retro-reflective mark is stuck on the plurality of battery cells 101, or a point is projected by a spot projector, or a probe rod is used. Point, so that the specific location of the changed battery cell 101 in the battery module case 10 and the specific location of the changed battery cell 101 can be specifically located.

In one embodiment, each of the cameras 310 is connected to an input terminal of the second detection unit 630, and an output terminal of the second detection unit 630 is connected to the control unit 610. The plurality of cameras 310 capture images of the plurality of battery cells 101 and transmit signals to the second detection unit 630 through a wire harness. The second detection unit 630 performs further recognition processing according to the grayscale difference of the picture. When one or more of the battery cells 101 are about to undergo or have run out of heat, the eruption accumulates inside the battery cells 101 to a certain pressure, and the battery packaging will swell and deform, and the soft pack battery is more obvious. When the internal gas pressure of the battery cell 101 exceeds the pressure limit of the hard-shell battery cell safety valve or soft bag, it will erupt to the outside of the battery cell 101, causing the battery to erupt outside the battery cell 101 Significant changes have occurred on the surface, such as the opening of the safety valve and cracks in the outer packaging film.

Such phenomena as swelling and deformation, opening of the safety valve, cracking of the outer packaging film, and eruption of the eruption can be clearly displayed on the image, and be timely fed back to the second detection unit 630. The second detection unit 630 performs image processing, converts image information into a digital signal, and feeds it back to the control unit 610. The control unit 610 uses this signal as a basis for issuing a fire warning signal. In the process of image recognition, such phenomena as swelling and deformation, opening of the safety valve, cracking of the outer packaging film, and eruption of eruption are reflected by the characteristic values such as the gray and shape of the image pixels. At the same time, by analyzing the picture information taken from the direction of looking down the safety valve 102, it is possible to identify the specific location where the battery emerges through the change in the gray level of the pixel, and quickly identify the early thermal runaway and eruption of the battery.

In one embodiment, the plurality of cameras 310 are infrared cameras, which have high accuracy, non-contact measurement, no contact, fast measurement speed, can be measured in an unstable environment, suitable for measurement in a narrow space, high data rate, Easy access to large amounts of data, good adaptability, and good portability. The types of the plurality of cameras 310 may be different.

In one embodiment, each of the battery cells 101 is provided with a safety valve 102. The safety valve 102 is disposed at an air outlet of the battery cell 101. For hard-shell batteries, such as cylindrical and rectangular batteries, when the safety valve 102 is generally installed and the battery cell 101 is about to undergo thermal runaway and a spray phenomenon occurs, the jetting position of the air flow is often through the safety Valve 102 is ejected. Considering that the eruption position is fixed and the airflow is distributed above the safety valve 102, it is possible to determine whether an eruption phenomenon occurs by monitoring the change in the gray value of the area above the safety valve 102. Therefore, since the gray value is different when there is airflow and no airflow above the safety valve 102, the camera is installed at the intersection of diagonal lines above the inner wall of the battery module case 10, and the camera A photographing device is disposed opposite to a plurality of the safety valves 102 for real-time monitoring.

The multiple cameras 310 are respectively connected to the battery management system 60, and can take pictures from multiple angles, which can quickly and accurately implement a large number of lithium-ion battery fire warnings, and can specifically locate one or more of the changes that occur. Battery cell 101. When one or more of the battery cells 101 show a spray phenomenon, the lower limit value of the safety valve 102 of the hard-shell battery and the soft-pack battery is often the position where the gaseous eruption is sprayed from the inside of the battery. Therefore, one or more of the cameras 310 need to be installed at a position overlooking the safety valve 102 as needed to comprehensively capture image information of key parts. In addition, the camera 310 may also be installed at different positions of the battery module casing 10 as needed to capture image information of battery expansion and deformation in all directions. The multiple cameras 310 can be used for a large number of fire alarms of the battery cells 101. For example, the multiple cameras 310 can be installed at different positions in the battery box, the structure is simple, and it is relatively easy to implement.

Referring to FIG. 4, in one embodiment, the camera 310 is disposed on an inner wall side 104 of the battery module housing 10 and is disposed near the inner wall top surface 103 so that the safety valve can be monitored in real time. 102 changes.

A plurality of the battery cells 101 in the battery module case 10 are often arranged side by side. A straight line can be connected at the center of the safety valve 102, and a plane a is formed through the straight line, the plane a is parallel to the surface of the safety valve 102, and the surface of the safety valve 102 is close to the safety valve 102. The inner wall surface of the battery module case 10 forms a closed rectangular parallelepiped or hexahedron. Among them, four faces b are perpendicular to the plane a, and each face b belongs to a part of the inner wall side surface 104. The plane a is parallel to the inner wall top surface 103 and has a certain distance. The plane a is a virtual plane provided to better confirm the installation position of the safety valve 102. The camera 310 may be provided with one camera 310 at the center of a plane b, or one camera 310 may be installed at the center of two adjacent faces b, that is, only two opposite faces b One of the cameras 310 may be installed on one of the faces b.

Referring to FIG. 5, in one embodiment, each of the battery cells 101 is provided with a safety valve 102, and a plurality of the safety valves 102 are opposite to the top surface 103 of the inner wall of the battery module housing 10. The camera 310 is disposed on an intersection of a plane where the center points of the plurality of safety valves 102 are connected and a vertical plane of the inner wall top surface 103. When the plane where the center points of the multiple safety valves 102 connect is perpendicular to the inner wall top surface 103, at this time, a vertical line intersects with the inner wall top surface 103, and the camera 310 is disposed on the At the intersection, a plurality of the safety valves 102 can be monitored at the most accurate position, and positioning can be accurately performed to confirm one or more of the battery cells 101 that will or will have thermal runaway. The center point of the safety valve 102 can be connected into a line, as shown by the dotted line in FIG. 6. When the installation position of the camera 310 in the top view is at the position of the dotted line, not only can it be determined whether a spraying phenomenon has occurred, but also the position of the battery cell 101 where the spraying phenomenon occurs can be located.

Referring to FIGS. 6-7, in one embodiment, the camera 310 is disposed at a top corner position of the inner wall top surface 103 of the battery module case 10.

Further, in order to reduce costs, the camera 310 is installed at a top corner of the battery module case 10. At this time, a certain distance should be maintained between the top of the battery cell 101 and the wall surface of the nearest battery module case 10 to ensure that the camera can fully capture the safety valves 102 of all the battery cells 101. The position shown only requires a camera, and it can be prepared to capture whether a battery ejection phenomenon has occurred and the position of the battery cell 101 where the ejection phenomenon has occurred.

In one embodiment, the battery fire early warning system further includes a spectrum analysis device 450. An input terminal of the spectrum analysis device 450 is connected to the third detection device 40, and an output terminal of the spectrum analysis device 450 is connected to the third detection unit 640.

During the eruption of the battery, the airflow rubs and collides with the wall surface at the exit and the surrounding air to cause vibration, which in turn causes air to vibrate and emit sound. Among them, the generated sound is closely related to the jet pressure, jet speed, nozzle shape, box structure, etc. of the airflow, and has unique characteristics that distinguish it from other voices. The sound collection device is used to collect sound waves emitted during the eruption of the battery cell 101, and transmit the sound wave signals to the spectrum analysis device 450. Therefore, the spectrum analysis device 450 performs a Fourier transform on the collected sound waves, and performs steps such as filtering and removing noise data to separate or demodulate complex signals into sine waves with different frequencies and amplitudes, and detects the The frequency characteristics and amplitude characteristics of the sound waves are transmitted to the third detection unit 640. The third detection unit 640 compares the frequency characteristics and amplitude characteristics of the collected acoustic waves with the frequency characteristics and amplitude characteristics of the target acoustic wave. If the frequency and amplitude of the collected sound wave appear to be the frequency distribution and amplitude distribution of the target sound wave, it can be considered that the spraying phenomenon of the battery cell 101 occurs, and the control unit 610 issues a fire alarm at this time.

In one embodiment, the spectrum analysis device 450 is a spectrum analyzer.

Referring to FIGS. 8-9, in an embodiment, the third detection device 40 includes a plurality of noise sensors 421 disposed on an inner wall of the battery module housing 10, and each of the noise sensors 421 and The input terminal of the spectrum analysis device 450 is connected.

The noise sensor 421 has a built-in capacitive electret microphone that is sensitive to sound. The collected sound waves cause the electret film in the microphone to vibrate, which results in a change in capacitance and a corresponding tiny voltage that changes to achieve the sound. Signal to electrical signal conversion. Sound as a kind of wave, frequency and amplitude have become important attributes describing sound waves. The larger the amplitude, the louder, the higher the frequency, and the higher the pitch. Another characteristic of sound is the timbre, which means that the frequency performance of different sounds always has distinctive characteristics in terms of waveforms. Different sounding bodies have different timbre due to their different materials and structures. By providing a plurality of the noise sensors 421 on the inner wall of the battery module casing 10, monitoring can be performed from different directions, and the phenomenon of missed detection is avoided.

In one embodiment, each of the noise sensors 421 is disposed at a geometric center of each inner wall surface of the battery module case 10. The shape of the battery module case 10 is not limited, and may be a rectangular parallelepiped, a cube, a cylinder, or the like. Each of the noise sensors 421 is disposed on the geometry of each inner wall surface of the battery module case 10. On the center, sound waves emitted during the eruption of one or more of the battery cells 101 can be captured from all directions.

Referring to FIGS. 10-11, in one embodiment, the noise sensor 421 is disposed on an inner wall side surface 104 of the battery module case 10 and is disposed near the inner wall top surface 103. A plurality of the battery cells 101 in the battery module case 10 are often arranged side by side. A straight line can be connected at the center of the safety valve 102, and a plane a is formed through the straight line, the plane a is parallel to the surface of the safety valve 102, and the surface of the safety valve 102 is close to the safety valve 102. The inner wall surface of the battery module case 10 forms a closed rectangular parallelepiped or hexahedron. Among them, four faces b are perpendicular to the plane a, and each face b belongs to a part of the inner wall side surface 104. The plane a is parallel to the inner wall top surface 103 and has a certain distance. The plane a is a virtual plane provided to better confirm the installation position of the safety valve 102. One noise sensor 421 is installed at the center of a plane b, or one noise sensor 421 may be installed at the center of two adjacent faces b, that is, only one of the two opposite faces b It is sufficient to install one of the noise sensors 421 on b.

Referring to FIG. 12, in one embodiment, the noise sensor 421 is disposed on a surface of each of the battery cells 101 and is disposed near the safety valve 102.

Referring to FIG. 13, in one embodiment, each of the safety valves 102 is disposed at an air outlet of each of the battery cells 101, and a plurality of the safety valves 102 and an inner wall of the battery module case 10 The top surface 103 is opposed.

In one embodiment, the noise sensor 421 is disposed on an intersection line of a plane where the center point line of the plurality of safety valves 102 is located and a vertical plane of the inner wall top surface 103. When the plane where the center points of the multiple safety valves 102 are connected is perpendicular to the inner wall top surface 103, at this time, a vertical line intersects with the inner wall top surface 103, and the noise sensor 421 is disposed at the At the intersection, a plurality of the safety valves 102 can be monitored. The center points of the safety valves 102 can be connected into a line.

Referring to FIGS. 14-15, in one embodiment, the noise sensor 421 is disposed at a vertex position of the top surface 103 of the inner wall of the battery module case 10. Further, in order to reduce costs, the noise sensor 421 is installed at a top corner of the battery module case 10. During the eruption of the battery, airflow noise is generated when the airflow is emitted from the inside of one or more of the battery cells 101 to the outside of the battery. The reason is that the airflow causes friction and collision with the wall surface at the exit and the surrounding air to cause vibration. This causes air to vibrate and emit sound. The sound collection device is used to collect sound waves emitted during the eruption of the battery cell 101, and transmit the sound wave signal to the spectrum analysis device 450. Therefore, the spectrum analysis device 450 performs a Fourier transform on the collected sound waves, and performs steps such as filtering and removing noise data to separate or demodulate complex signals into sine waves with different frequencies and amplitudes, and detects the The frequency characteristics and amplitude characteristics of the sound waves are transmitted to the third detection unit 640. The third detection unit 640 compares the frequency characteristics and amplitude characteristics of the collected acoustic waves with the frequency characteristics and amplitude characteristics of the target acoustic wave. If the frequency and amplitude of the collected sound wave appear to be the frequency distribution and amplitude distribution of the target sound wave, it can be considered that the spraying phenomenon of the battery cell 101 occurs, and the control unit 610 issues a fire alarm at this time.

In one embodiment, a battery fire warning method may be applied to the battery fire warning system 100 described above. The battery fire early warning method includes:

S10. Obtain first signal parameters of a plurality of battery cells 101 in the battery module housing 10 according to the second detection device 30 and the fourth sensor 50.

S20. According to the first signal parameter, the control unit 610 issues a warning signal.

S30. When the control unit 610 issues a warning signal, according to the second detection device 30 and the third detection device 40, obtain a second signal of the plurality of battery cells 101 in the battery module case 10. parameter;

S40. According to the second signal parameter, the control unit 610 issues a fire warning signal;

S50. When the control unit 610 issues a fire warning signal, according to the first detection device 20, obtain a third signal parameter of the plurality of battery cells 101 in the battery module housing 10; and

S60. According to the third signal parameter, the control unit 610 sends an escape signal.

In the step S20, since the second detection device 30 and the fourth detection device 50 can detect corresponding signals before one or more of the battery cells 101 show a spray phenomenon, the first The two detection devices 30 and the fourth detection device 50 are used as the first signal in parallel, that is, when one or more of the battery cells 101 do not show a spray phenomenon, but one or more of the battery cells 101 exhibit expansion deformation, When the temperature increases and the squeezing force between the adjacent monomers 101 increases and exceeds a certain limit, the control unit 610 should issue a warning signal to remind "the battery needs to be repaired."

In step S40, when one or more of the battery cells 101 show a spray phenomenon, the second detection device 30 and the third detection device 40 will first detect the corresponding safety valve 102. Signals such as opening or cracking of the outer package, specific noise vibration frequency, etc., and using this as the second signal parameter, the control unit 610 should issue a fire warning signal to remind "please evacuate urgently" and start the automatic fire extinguishing device.

In step S60, when the smoke diffuses to the first detection device 20, the first detection device 20 will detect that a specific component such as H ₂ , CO ₂ and other flammable and explosive gases exceeds a certain amount. Concentration, and using this as the third signal parameter, the control unit 610 should issue an escape signal to remind "the fire is about to occur, please emergency escape". Detecting the image, gas, sound, temperature, and surface stress of one or more of the battery cells 101 by the first detection device 20, the second detection device 30, the third detection device 40, and the fourth detection device 50 , Squeezing force and other signal information. The first detection unit 620, the second detection unit 630, the third detection unit 640, and the fourth detection unit 650 transmit corresponding signal information to the control unit 610 of the battery management system 60, The control unit 610 judges according to the corresponding signal information, determines whether to issue a fire warning signal and the type of the signal, and warns the driver, the passenger or the car to perform corresponding processing.

In one embodiment, in the step of obtaining the first signal parameters of the plurality of battery cells 101 in the battery module housing 10 according to the second detection device 30 and the fourth detection device 50, the first signal parameters are First image characteristic parameters of the plurality of battery cells 101 and surface temperature parameters of the plurality of battery cells 101.

The plurality of cameras 310 are respectively disposed on diagonal lines of each inner wall surface of the battery module housing 10 to monitor the plurality of battery cells 101 in all directions and collect the plurality of batteries. Images at different locations of cell 101. The plurality of cameras 310 are used to capture images of changes in the plurality of battery cells 101, such as battery expansion, safety valve opening, outer packaging film rupture, and battery eruption. The second detection unit 630 further identifies a change situation of the images of the plurality of battery cells 101 according to a grayscale difference of pictures. Image processing according to the images of the plurality of battery cells 101 includes image preprocessing, image segmentation, feature value extraction, etc., converting image information of the images of the plurality of battery cells 101 into digital signals, and according to the image grayscale The change judges whether an air flow eruption or a change in the shape of the battery has occurred.

Among them, useful information is identified after processing according to the gray difference of the picture. The gray value of an image is generally quantified into different gray levels. When one or more of the battery cells 101 are changed, the gray value of the collected image will change accordingly, which will be different from the normal battery cell. By comparing the gray values of the images, information such as the position and number of the battery cells 101 where thermal runaway occurs can be obtained. The feature parameter is a gray value that changes in each image. When the battery cell 101 erupts, the corresponding gray value in the image of the battery cell 101 will change at the corresponding part of the battery cell 101. When the battery cells 101 swell, the gray value of the area between the battery cells 101 changes. Through the images of the plurality of battery cells 101, changes such as swelling and deformation of one or more of the battery cells 101, opening of the safety valve, cracking of the outer packaging film, and eruption of the eruption can be changed through gray in the acquired image The degree value is reflected. When comparing changes in one or more of the battery cells 101, it may be compared with the gray value of the image of the battery cell in a normal state, and the part where the gray value changes in the collected image is a thermal runaway. position.

In one embodiment, an image recognition algorithm using a neural network is used to obtain the first image feature parameters and the second image feature parameters. An image recognition method is adopted when acquiring changes of the plurality of battery cells 101. Generally, an image recognition method based on a neural network, an image recognition method based on a wavelet moment, and the like are generally used.

Changes in the images of the plurality of battery cells 101 are further identified according to the grayscale difference of the pictures. When one or more of the battery cells 101 swell, a gray value of a region between adjacent battery cells 101 changes, and is fed back to the control unit 610. The control unit 610 issues a battery failure warning. When in the running state, the control unit 610 warns the entire vehicle or powers off and does not output current for control. When in the charging state, the control unit 610 raises an alarm to the charger, and the charger stops charging. When the battery cell 101 erupts, there is a gaseous eruption around the safety valve 102, which causes a change in the gray value of the image around the safety valve 102. At this time, when the second detection unit 630 recognizes that the gray value has changed, the feedback is sent to the control unit 610, and the control unit 610 issues a fire warning. For a soft pack battery, when the battery cell 101 erupts, the gray value of the area between the adjacent battery cells 101 changes, and is fed back to the control unit 610, and the control unit 610 issues a fire warning.

In one embodiment, when the control unit 610 issues a warning signal, the plurality of battery cells in the battery module case 10 are obtained according to the second detection device 30 and the third detection device 40. In the step of the second signal parameter of 101, the second signal parameter is a second image characteristic parameter of the plurality of battery cells 101 and a frequency characteristic and an amplitude characteristic of a sound wave. The frequency distribution of the jet noise during the battery eruption is determined in the silent test room, and it is observed whether it is mainly low frequency, or medium and high frequency, and the proportion distribution of the three. The change law of the target to obtain the target frequency characteristics.

According to the spectrum division table formulated by the Institute of Electrical and Electronics Engineers (IEEE), the low frequency is 30 to 300 kHz, the intermediate frequency is 300 to 3000 kHz, the high frequency is 3 to 30 MHz, and the frequency range 30 to 300 MHz is very high frequency. 300 ~ 1000MHz is UHF. Compared with low-frequency signals, high-frequency signals change very quickly and have abrupt changes; low-frequency signals change slowly and the waveform is smooth. Because the spray phenomenon occurs after a certain pressure is accumulated inside the battery, the rate is faster at the beginning of the spray and gradually decreases, so the corresponding frequency does not change periodically. The focus is on the frequency and amplitude distribution of the noise at the moment of battery eruption, so that the relevant signals can be captured and fire warnings issued in time when the battery has just emerged.

The battery cells in one battery module are split and only one of them is kept, and the battery module box containing only one battery cell is placed in a silent laboratory. Through certain abuse methods, such as electrical abuse, thermal abuse, mechanical abuse, etc., the battery is ejected, and its frequency characteristics and amplitude characteristics are obtained through spectrum analysis. Through multiple experiments, the general target frequency characteristics and amplitude characteristics can be obtained during the battery eruption process, and the variation of the amplitude distribution with the injection process can be observed to obtain various possibilities for the target frequency characteristics and amplitude characteristics. Therefore, the characteristic frequency and characteristic amplitude during battery cell eruption are extracted as the basis for judging whether or not the battery has an appearance phenomenon, that is, the frequency characteristic and amplitude characteristic of the target acoustic wave.

The acquired frequency characteristic and amplitude characteristic corresponding to the acoustic wave are compared with the target frequency characteristic and target amplitude characteristic. If the acquired frequency characteristic and amplitude characteristic corresponding to the acoustic wave include the target frequency characteristic and the target amplitude characteristic, then It can be determined that one or more of the battery cells 101 have been sprayed, and a fire warning signal should be issued at this time. Otherwise, it is considered that no spraying phenomenon has occurred.

The technical features of the embodiments described above can be arbitrarily combined. In order to simplify the description, all possible combinations of the technical features in the above embodiments have not been described. However, as long as there is no contradiction in the combination of these technical features, It should be considered as the scope described in this specification.

The above-mentioned embodiments only express several implementation manners of the present application, and their descriptions are more specific and detailed, but they cannot be understood as limiting the scope of patents of the present application. It should be noted that, for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can be made, which all belong to the protection scope of the present application. Therefore, the protection scope of this application patent shall be subject to the appended claims.

Finally, it should be noted that in this article, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply these entities. There is any such actual relationship or order between OR operations. Moreover, the terms "including", "comprising", or any other variation thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or device that includes a series of elements includes not only those elements but also those that are not explicitly listed Or other elements inherent to such a process, method, article, or device. Without more restrictions, the elements defined by the sentence "including a ..." do not exclude the existence of other identical elements in the process, method, article, or equipment including the elements.

The embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same and similar parts between the embodiments, refer to each other.

The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the application. Therefore, this application will not be limited to the embodiments shown herein, but should conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims (20)

1. A battery fire early warning system includes:

   A battery module casing (10), wherein a plurality of battery cells (101) are arranged in the battery module casing (10), and each of the battery cells (101) is provided with a safety valve (102);

   At least one first detection device (20) is disposed on the inner wall of the battery module housing (10), and the first detection device (20) is disposed opposite to a plurality of the safety valves (102) and is disposed on the detection The electrolyte or soot particles released when the battery cell (101) is about to be or has been thermally out of control;

   At least one second detection device (30) is disposed on the inner wall of the battery module housing (10), and the second detection device (30) is disposed opposite to a plurality of the safety valves (102) and is disposed on the detection A shape change of the plurality of battery cells (101) when the thermal runaway is about to occur or has occurred;

   At least one third detection device (40) is disposed on the inner wall of the battery module casing (10), and the third detection device (40) is disposed opposite to a plurality of the safety valves (102) and is disposed on the acquisition Sound waves generated by airflow ejection during the eruption when the plurality of battery cells (101) are about to undergo or have thermal runaway;

   A plurality of fourth detection devices (50), each of which is disposed on a surface of each of the battery cells (101) or between two battery cells, and is provided for detecting the plurality of Changes in battery cell surface temperature, surface strain force, or squeezing force between two battery cells when the battery cell (101) is about to undergo thermal runaway; or

   A battery management system (60), the first detection device (20) is connected to the battery management system (60), the second detection device (30) is connected to the battery management system (60), and the first Three detection devices (40) are connected to the battery management system (60), and the plurality of fourth detection devices (50) are connected to the battery management system (60).
2. The battery fire early warning system according to claim 1, wherein the first detection device (20) is a smoke sensor or a gas sensor.
3. The battery fire early warning system according to claim 1, wherein the second detection device (30) is a photographing device.
4. The battery fire early warning system according to claim 1, wherein the third detection device (40) is a sound collection device.
5. The battery fire early warning system according to claim 1, wherein the fourth detection device (50) is a temperature sensor.
6. The battery fire early warning system according to claim 1, wherein the battery management system (60) comprises:

   Control unit (610);

   A first detection unit (620), an input of the first detection unit (620) is connected to the first detection device (20), and an output of the first detection unit (620) is connected to the control unit ( 610) connection;

   A second detection unit (630), an input of the second detection unit (630) is connected to the second detection device (30), and an output of the second detection unit (630) is connected to the control unit ( 610) connection;

   A third detection unit (640), an input of the third detection unit (640) is connected to the third detection device, and an output of the third detection unit (640) is connected to the control unit (610) ;as well as

   A fourth detection unit (650), an input of the fourth detection unit (650) is connected to the plurality of fourth detection devices (50), and an output of the fourth detection unit (650) is connected to the control The unit (610) is connected.
7. The battery fire early warning system according to claim 6, further comprising a fire extinguishing device (70), wherein the fire extinguishing device (70) is connected to the control unit (610).
8. The battery fire early warning system according to claim 3, wherein the second detection device (30) comprises:

   A plurality of cameras (310) are disposed on an inner wall of the battery module housing (10), and each of the cameras (310) is connected to the battery management system (60).
9. The battery fire early warning system according to claim 8, characterized in that each of the cameras (310) is disposed on a geometric center of each inner wall surface of the battery module housing (10) and is positioned accurately The position of the plurality of battery cells (101).
10. The battery fire early warning system according to claim 9, wherein each of the cameras (310) is connected to an input terminal of the second detection unit (630), and an output of the second detection unit (630) The terminal is connected with the control unit (610).
11. The battery fire early warning system according to claim 8, wherein the plurality of cameras (310) are infrared cameras.
12. The battery fire early warning system according to claim 4, wherein the battery fire early warning system further comprises:

    A spectrum analysis device (450), an input end of the spectrum analysis device (450) is connected to the third detection device (40), and an output end of the spectrum analysis device (450) is connected to the third detection unit ( 640) connection.
13. The battery fire early warning system according to claim 12, wherein the third detection device (40) comprises a plurality of noise sensors (421) disposed on an inner wall of the battery module casing (10), and Each of the noise sensors (421) is connected to an input terminal of the spectrum analysis device (450).
14. The battery fire early warning system according to claim 13, wherein each of the noise sensors (421) is disposed at a geometric center of each inner wall surface of the battery module case (10).
15. The battery fire early warning system according to claim 13, wherein each of the safety valves (102) is provided at an air outlet of each of the battery cells (101), and a plurality of the safety valves (102) Opposite the top surface (103) of the inner wall of the battery module casing (10).
16. The battery fire early warning system according to claim 15, wherein the noise sensor (421) is disposed on an inner wall side surface (104) of the battery module case (10), and is close to the inner wall top surface ( 103) Settings.
17. The battery fire early warning system according to claim 13, wherein the noise sensor (421) is disposed on a surface of each of the battery cells (101) and is disposed near the safety valve (102).
18. A battery fire early warning method includes:

    S10. Obtain first signal parameters of a plurality of battery cells (101) in the battery module housing (10) according to the second detection device (30) and the fourth sensing device (50).

    S20. According to the first signal parameter, the control unit (610) issues a warning signal;

    S30. When the control unit (610) issues a warning signal, according to the second detection device (30) and the third detection device (40), obtain the plurality of cells in the battery module casing (10). A second signal parameter of the battery cell (101);

    S40. According to the second signal parameter, the control unit (610) issues a fire warning signal;

    S50. When the control unit (610) issues a fire early warning signal, obtain a third of the plurality of battery cells (101) in the battery module housing (10) according to a first detection device (20). Signal parameters; and

    S60. According to the third signal parameter, the control unit (610) sends an escape signal.
19. The battery fire early warning method according to claim 18, wherein a plurality of battery cells (10) in the battery module casing (10) are obtained based on the second detection device (30) and the fourth detection device (50). In the step of the first signal parameter of 101), the first signal parameter is a first image characteristic parameter of the plurality of battery cells (101) and a surface temperature parameter of the plurality of battery cells (101).
20. The battery fire early warning method according to claim 18, wherein when the control unit (610) sends out a warning signal, the control unit (610) obtains all information based on the second detection device (30) and the third detection device (40). In the step of the second signal parameter of the plurality of battery cells (101) in the battery module casing (10), the second signal parameter is a second signal parameter of the plurality of battery cells (101) Image characteristic parameters and frequency and amplitude characteristics of sound waves.

Images