Electric vehicle thermal runaway warning and suppression system and control method thereof

Abstract

The present invention discloses an electric vehicle thermal runaway warning and suppression system and a control method thereof, belonging to the technical field of electric vehicle thermal runaway warning and suppression; the technical problem to be solved is: to provide an improvement in the hardware structure of an electric vehicle thermal runaway warning and suppression system; the technical scheme adopted to solve the above technical problem is: comprising an electric vehicle body, the electric vehicle body comprising a power battery and a vehicle controller; a thermal runaway suppression unit is arranged outside the power battery, and a battery module, a battery management unit, and a thermal runaway warning unit are arranged inside the power battery; the thermal runaway suppression unit comprises a fire extinguishing agent, an injector, and a suppression controller, and the thermal runaway warning unit comprises a combustible gas concentration sensor, a temperature sensing cable, and a warning controller, and the combustible gas concentration sensor and the temperature sensing cable are arranged inside the power battery; the present invention is applied to electric vehicles.

Description

Technical Field

[0001] The invention discloses an electric vehicle thermal runaway warning and suppression system and a control method thereof, belonging to the technical field of electric vehicle thermal runaway warning and suppression. Background Art

[0002] The development of electric vehicles has placed higher and higher requirements on the energy density of power batteries. The high energy density of lithium-ion batteries is often accompanied by high safety risks. In recent years, battery fires have occurred frequently, and battery safety has become one of the research hotspots in the automotive industry.

[0003] Thermal runaway is a phenomenon in which the battery temperature rises uncontrollably due to a chain reaction of heat release from battery cells. Battery thermal runaway may be caused by mechanical collision, internal short circuit, etc. Among them, internal short circuit may also be caused by impurity particles introduced during the battery production process penetrating the battery diaphragm, or by lithium deposition during the use of the battery, which pierces the battery diaphragm. At present, power battery technology is still in the development stage, and design solutions, production processes, use and maintenance still need to be improved. Battery thermal runaway cannot be completely avoided.

[0004] Due to the lack of effective monitoring and prevention technology, thermal runaway occurs and nothing can be done, which eventually leads to battery pack fire and even burns the whole vehicle. In addition, the owner generally cannot get a fire warning. Battery fire not only causes damage to the vehicle, but sometimes also poses a great safety hazard to the property around the accident vehicle. Therefore, it is necessary to provide an electric vehicle thermal runaway warning, suppression system and control method. Summary of the invention

[0005] In order to solve the deficiencies in the prior art, the present invention aims to provide an improvement in the hardware structure of a thermal runaway warning and suppression system for an electric vehicle.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows: comprising an electric vehicle body, the electric vehicle body comprising a power battery and an automobile controller;

[0007] A thermal runaway suppression unit is disposed outside the power battery, and a battery module, a battery management unit, and a thermal runaway warning unit are disposed inside the power battery;

[0008] The thermal runaway suppression unit includes a fire extinguishing agent, an injector, and a suppression controller, wherein the injector is arranged at the output end of the fire extinguishing agent, the injector is connected to a fire extinguishing agent nozzle through a fire extinguishing agent transmission pipeline, and the fire extinguishing agent nozzle is arranged inside the power battery;

[0009] The battery management unit includes a battery controller, a voltage acquisition module and a temperature acquisition module, and the voltage acquisition module and the temperature acquisition module are arranged around a single cell inside the power battery;

[0010] The thermal runaway warning unit includes a combustible gas concentration sensor, a temperature sensing cable, and a warning controller, wherein the combustible gas concentration sensor and the temperature sensing cable are arranged inside the power battery;

[0011] The automobile controller is connected to the warning controller, the suppression controller, and the battery controller respectively through wires, and the signal output end of the combustible gas concentration sensor and the signal control end of the temperature sensing cable are connected to the warning controller through an AD conversion module;

[0012] The suppression controller is connected to the control end of the injector through a wire and is used to control the injector to open or close the fire extinguishing agent nozzle.

[0013] The driving room of the electric vehicle body is provided with an instrument and an on-board terminal;

[0014] The instrument is provided with a thermal runaway warning fault position and a thermal runaway suppression fault position;

[0015] The automobile controller is also connected to the instrument and the vehicle-mounted terminal respectively through wires, and the vehicle-mounted terminal is wirelessly connected to the automobile monitoring platform and the mobile terminal through a wireless network.

[0016] The battery controller is connected to a voltage acquisition module and a temperature acquisition module through wires, respectively. The voltage acquisition module is used to acquire voltage data of a power battery cell or a minimum parallel unit, and the temperature acquisition module is used to acquire temperature data of a power battery cell.

[0017] The vehicle controller is also connected to a GPS module via a wire to obtain real-time location information of the electric vehicle body.

[0018] The automobile controller is also connected to the vehicle speed sensor through a wire.

[0019] A thermal runaway warning and suppression control method for electric vehicles comprises the following steps:

[0020] Step 1: Control the vehicle speed sensor to collect data and send it to the vehicle controller, control the battery management unit and the thermal runaway warning unit to collect thermal runaway data and send it to the vehicle controller, the thermal runaway data includes the voltage data of a single cell or the minimum parallel unit of the power battery, the temperature data of a single cell, the ambient temperature data, and the combustible gas concentration data;

[0021] Step 2: The vehicle controller analyzes and processes the vehicle speed data collected by the vehicle speed sensor, and the steps are as follows:

[0022] Step 2.1: When the speed sensor data is continuously 0, it is determined that the electric vehicle is in a stopped state, and the process goes to step 3;

[0023] Step 2.2: When the data of the vehicle speed sensor is greater than 0, it is determined that the electric vehicle is in a driving state, and the process goes to step 4;

[0024] Step 2.3: When it is determined through step 2.1 that the electric vehicle body is in a stopped state and the power battery is detected to be in a charging state, the process proceeds to step 5;

[0025] Step 3: The vehicle controller will make a threshold judgment on the thermal runaway data. When the thermal runaway data is within the normal threshold, the electric vehicle body will stop driving normally. When any thermal runaway data exceeds the normal threshold, including the combustible gas CO concentration greater than 300ppm, the single cell temperature rise greater than 10℃ / 10s, and the temperature sensing cable is triggered, the vehicle controller will execute the abnormal state instruction 1 and send the fault information 1 to the vehicle monitoring platform and mobile terminal;

[0026] Step 4: The vehicle controller will make a threshold judgment on the thermal runaway data. When the thermal runaway data is within the normal threshold, the electric vehicle body will continue to drive. When any thermal runaway data exceeds the normal threshold, including the combustible gas CO concentration greater than 300ppm, the single cell temperature rise greater than 10℃ / 10s, and the temperature sensing cable is triggered, the vehicle controller will execute the abnormal state instruction 2 and send the fault information 2 to the vehicle monitoring platform and mobile terminal;

[0027] Step 5: The vehicle controller will make a threshold judgment on the thermal runaway data. When the thermal runaway data is within the normal threshold, the battery continues to charge. When any thermal runaway data exceeds the normal threshold, including the combustible gas CO concentration greater than 300ppm, the single cell temperature rise greater than 10℃ / 10s, and the temperature sensing cable is triggered, the vehicle controller will execute the abnormal status instruction three and send the fault information three to the vehicle monitoring platform and mobile terminal.

[0028] The execution status abnormal instruction 1 in the step 3 is specifically: first, the controller is inhibited from controlling the injector to open and inject the fire extinguishing agent into the power battery; secondly, the vehicle monitoring platform displays a thermal runaway warning fault; and finally, the mobile terminal displays a thermal runaway warning fault; the fault information 1 includes the vehicle monitoring platform displaying that the fire extinguishing agent has been injected, the mobile terminal displaying that the fire extinguishing agent has been injected, and at the same time, the vehicle controller controls the vehicle to be unable to power on.

[0029] The execution state abnormal instruction 2 in step 4 is specifically as follows: first, the vehicle controller controls the thermal runaway warning fault position alarm prompt on the instrument, and at the same time controls the electric vehicle body to drive at a limited speed, the vehicle monitoring platform to display the thermal runaway warning fault, the mobile terminal to display the thermal runaway warning fault, and delays for a period of time to cut off the high voltage of the vehicle, and then the suppression controller controls the injector to start and spray the fire extinguishing agent into the power battery;

[0030] The second fault information includes that the vehicle monitoring platform shows that the fire extinguishing agent has been sprayed, the mobile terminal shows that the fire extinguishing agent has been sprayed, and at the same time the vehicle controller controls the vehicle to limit the speed and stop quickly, and the vehicle cannot be powered on again.

[0031] The execution status abnormal instruction three in the step five is specifically: first, the charging battery switch is cut off, and at the same time, the controller is inhibited from controlling the injector to open and inject the fire extinguishing agent into the power battery; secondly, the vehicle monitoring platform displays a thermal runaway warning fault, and finally the mobile terminal displays a thermal runaway warning fault; the fault information one includes the vehicle monitoring platform showing that the fire extinguishing agent has been injected, the mobile terminal showing that the fire extinguishing agent has been injected, and at the same time the vehicle controller controls the vehicle to be unable to power on.

[0032] The beneficial effects of the present invention compared with the prior art are as follows: by arranging combustible gas concentration sensors and temperature sensing cables around the battery, the thermal runaway warning unit collects relevant physical quantities, the vehicle controller analyzes and judges the thermal runaway data, and transmits it to the thermal runaway suppression unit, sprays a fire extinguishing agent, dilutes the combustible gas concentration, reduces the temperature in the battery pack, suppresses the occurrence and spread of thermal runaway, and reduces the occurrence of battery fires from a time dimension; the vehicle controller can extract parameter information related to thermal runaway, improves the warning and suppression response speed for thermal runaway situations in electric vehicles, and thereby improves the safety of electric vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The present invention will be further described below in conjunction with the accompanying drawings:

[0034] Figure 1 It is a structural schematic diagram of the present invention;

[0035] Figure 2 It is a schematic structural diagram of a thermal runaway suppression unit of the present invention;

[0036] Figure 3 It is a schematic diagram of the circuit structure of the present invention;

[0037] Figure 4 This is a flow chart of the thermal runaway early warning and suppression control method of the electric vehicle in driving state of the present invention;

[0038] Figure 5 This is a flow chart of the thermal runaway early warning and suppression control method for the charging state of an electric vehicle according to the present invention;

[0039] Figure 6 The present invention is a flow chart of the thermal runaway early warning and suppression control method for an electric vehicle in a stopped state.

[0040] In the figure: 1 is the electric vehicle body, 2 is the power battery, 3 is the vehicle controller, 4 is the instrument, 5 is the vehicle terminal, 6 is the thermal runaway suppression unit, 7 is the battery module, 8 is the battery management unit, 9 is the thermal runaway warning unit, 10 is the fire extinguishing agent nozzle, 11 is the fire extinguishing agent transmission pipeline, 12 is the combustible gas concentration sensor, 13 is the temperature sensing cable, 14 is the warning controller, 15 is the fire extinguishing agent, 16 is the injector, 17 is the suppression controller, 18 is the AD conversion module, 19 is the wireless network, 20 is the vehicle monitoring platform, 21 is the mobile terminal, 31 is the GPS module, 32 is the vehicle speed sensor, 41 is the thermal runaway warning fault position, 42 is the thermal runaway suppression fault position, 81 is the battery controller, 82 is the voltage acquisition module, and 83 is the temperature acquisition module. DETAILED DESCRIPTION

[0041] like Figures 1 to 6 As shown, a thermal runaway warning and suppression system for electric vehicles of the present invention comprises an electric vehicle body 1, wherein the electric vehicle body 1 comprises a power battery 2 and an automobile controller 3;

[0042] A thermal runaway suppression unit 6 is disposed outside the power battery 2, and a battery module 7, a battery management unit 8, and a thermal runaway warning unit 9 are disposed inside the power battery 2;

[0043] The thermal runaway suppression unit 6 includes a fire extinguishing agent 15, an injector 16, and a suppression controller 17. The injector 16 is disposed at the output end of the fire extinguishing agent 15. The injector 16 is connected to a fire extinguishing agent nozzle 10 through a fire extinguishing agent delivery pipeline 11. The fire extinguishing agent nozzle 10 is disposed inside the power battery 2.

[0044] The battery management unit 8 includes a battery controller 81, a voltage acquisition module 82 and a temperature acquisition module 83, and the voltage acquisition module 82 and the temperature acquisition module 83 are arranged around the single cell inside the power battery 2;

[0045] The thermal runaway warning unit 9 includes a combustible gas concentration sensor 12, a temperature sensing cable 13, and a warning controller 14. The combustible gas concentration sensor 12 and the temperature sensing cable 13 are arranged inside the power battery 2.

[0046] The automobile controller 3 is connected to the warning controller 14, the suppression controller 17, and the battery controller 81 through wires, and the signal output end of the combustible gas concentration sensor 12 and the signal control end of the temperature sensing cable 13 are connected to the warning controller 14 through the AD conversion module 18;

[0047] The suppression controller 17 is connected to the control end of the injector 16 via a wire, and is used to control the injector 16 to open or close the fire extinguishing agent nozzle 10 .

[0048] The driving room of the electric vehicle body 1 is provided with an instrument 4 and an on-board terminal 5;

[0049] The instrument 4 is provided with a thermal runaway warning fault position 41 and a thermal runaway suppression fault position 42;

[0050] The automobile controller 2 is also connected to the instrument 4 and the vehicle terminal 5 through wires, and the vehicle terminal 5 is wirelessly connected to the automobile monitoring platform 20 and the mobile terminal 21 through a wireless network 19.

[0051] The battery controller 81 is connected to a voltage acquisition module 82 and a temperature acquisition module 83 through wires, respectively. The voltage acquisition module 82 is used to acquire voltage data of a power battery cell or a minimum parallel unit, and the temperature acquisition module 83 is used to acquire temperature data of a power battery cell.

[0052] The vehicle controller 3 is also connected to the GPS module 31 via a wire to obtain real-time location information of the electric vehicle body 1 .

[0053] The vehicle controller 3 is also connected to a vehicle speed sensor 32 via a wire.

[0054] A thermal runaway warning and suppression control method for electric vehicles comprises the following steps:

[0055] Step 1: Control the vehicle speed sensor 32 to collect data and send it to the vehicle controller 3, control the battery management unit 8 and the thermal runaway warning unit 9 to collect thermal runaway data and send it to the vehicle controller 3, the thermal runaway data includes the voltage data of a single cell or the minimum parallel unit of the power battery 2, the temperature data of a single cell, the ambient temperature data, and the combustible gas concentration data;

[0056] Step 2: The vehicle controller 3 analyzes and processes the vehicle speed data collected by the vehicle speed sensor 32, and the steps are as follows:

[0057] Step 2.1: When the data of the vehicle speed sensor 32 is continuously 0, it is determined that the electric vehicle body 1 is in a stopped state, and the process goes to step 3;

[0058] Step 2.2: When the data of the vehicle speed sensor 32 is greater than 0, it is determined that the electric vehicle body 1 is in a driving state, and the process goes to step 4;

[0059] Step 2.3: When it is determined through step 2.1 that the electric vehicle body 1 is in a stopped state and the power battery 2 is monitored to be in a charging state, the process proceeds to step 5;

[0060] Step 3: The vehicle controller 3 performs threshold judgment on the thermal runaway data. When the thermal runaway data is within the normal threshold, the electric vehicle body 1 stops driving normally. When any thermal runaway data exceeds the normal threshold, including the combustible gas CO concentration greater than 300ppm, the single cell temperature rise greater than 10℃ / 10s, and the temperature sensing cable is triggered, the vehicle controller 3 executes the abnormal state instruction 1 and sends the fault information 1 to the vehicle monitoring platform 20 and the mobile terminal 21;

[0061] Step 4: The vehicle controller 3 performs threshold judgment on the thermal runaway data. When the thermal runaway data is within the normal threshold, the electric vehicle body 1 continues to drive. When any thermal runaway data exceeds the normal threshold, including the combustible gas CO concentration greater than 300ppm, the single cell temperature rise greater than 10℃ / 10s, and the temperature sensing cable is triggered, the vehicle controller 3 executes the abnormal state instruction 2 and sends the fault information 2 to the vehicle monitoring platform 20 and the mobile terminal 21;

[0062] Step 5: The vehicle controller 3 performs threshold judgment on the thermal runaway data. When the thermal runaway data is within the normal threshold, the battery continues to charge. When any thermal runaway data exceeds the normal threshold, including the combustible gas CO concentration greater than 300ppm, the single cell temperature rise greater than 10℃ / 10s, and the temperature sensing cable is triggered, the vehicle controller 3 executes the status abnormality instruction three and sends the fault information three to the vehicle monitoring platform 20 and the mobile terminal 21.

[0063] The execution status abnormal instruction 1 in the step 3 is specifically: first, the controller 17 is suppressed from controlling the injector 16 to start spraying the fire extinguishing agent into the power battery 2; secondly, the vehicle monitoring platform 20 displays a thermal runaway warning fault; and finally, the mobile terminal 21 displays a thermal runaway warning fault; the fault information 1 includes that the vehicle monitoring platform 20 displays that the fire extinguishing agent has been sprayed, the mobile terminal 21 displays that the fire extinguishing agent has been sprayed, and at the same time, the vehicle controller 3 controls the vehicle to be unable to power on.

[0064] The execution state abnormal instruction 2 in step 4 is specifically as follows: first, the automobile controller 2 controls the thermal runaway warning fault position 41 on the instrument 4 to give an alarm prompt, and at the same time controls the electric vehicle body 1 to travel at a limited speed, the automobile monitoring platform 20 to display a thermal runaway warning fault, and the mobile terminal 21 to display a thermal runaway warning fault, and delays for a period of time to cut off the high voltage of the automobile, and then the suppression controller 17 controls the injector 16 to start and inject the fire extinguishing agent into the power battery 2;

[0065] The second fault information includes that the vehicle monitoring platform 20 shows that the fire extinguishing agent has been sprayed, the mobile terminal 21 shows that the fire extinguishing agent has been sprayed, and at the same time the vehicle controller 3 controls the vehicle to drive at a limited speed and quickly stop driving, and the vehicle cannot be powered on again.

[0066] The execution status abnormal instruction three in the step five is specifically: first, the charging battery switch is cut off, and at the same time, the controller 17 is inhibited from controlling the injector 16 to open and inject the fire extinguishing agent into the power battery 2; secondly, the vehicle monitoring platform 20 displays a thermal runaway warning fault; and finally, the mobile terminal 21 displays a thermal runaway warning fault; the fault information one includes that the vehicle monitoring platform 20 displays that the fire extinguishing agent has been injected, the mobile terminal 21 displays that the fire extinguishing agent has been injected, and at the same time, the vehicle controller 3 controls the vehicle to be unable to power on.

[0067] The present invention provides a highly safe electric vehicle with thermal runaway warning and suppression functions. A power battery 2 is arranged at the bottom of the electric vehicle body 1, and a thermal runaway warning unit 9 is arranged inside the power battery 2. The thermal runaway warning unit 9 monitors battery data in real time to achieve effective warning of battery thermal runaway. The power battery 2 also includes a battery management unit 8, which includes a battery controller 81, a voltage acquisition module 82, and a temperature acquisition module 83. The voltage acquisition module 82 is arranged at the output end of the single cell of the battery module 7 for collecting voltage data of a single cell or a minimum parallel unit. The temperature acquisition module 83 is arranged on the outside of the single cell to collect temperature data of the single cell.

[0068] Secondly, a thermal runaway suppression unit 6 linked to the thermal runaway warning unit 9 is arranged outside the power battery 2. When the thermal runaway warning unit 9 and the battery management unit 8 detect battery thermal runaway information, including information on increased concentration of combustible particles, information on sudden increase in local temperature, and information on sudden drop in voltage of single cells, the information on increased concentration of combustible particles is detected by a combustible gas concentration sensor 12 arranged around the battery module 7, and the information on sudden increase in local temperature is detected by a temperature sensing cable 13 or a temperature sensor, i.e., a temperature acquisition module 83, arranged around the battery module 7. The output signal of the temperature sensing cable 13 is a switch signal, which is normally open when there is no fire alarm and normally closed when there is a fire alarm. The sudden drop in voltage of single cells is detected by a voltage acquisition module 82. The vehicle controller 3 controls the suppression controller 17 of the thermal runaway suppression unit 6 to start the injector 16, spray the fire extinguishing agent, and suppress the expansion of thermal runaway.

[0069] At the same time, the thermal runaway warning unit 9 and the thermal runaway suppression unit 6 can also send fault information to the vehicle controller 3 through the CAN bus. The vehicle controller 3 sends the fault information to the vehicle terminal 5 through the CAN bus, and at the same time, the thermal runaway warning fault bit 41 and the thermal runaway suppression fault bit 42 of the instrument 4 are activated, so that the driver in the cab can obtain the thermal runaway warning information in time to avoid the expansion of danger. The thermal runaway warning fault bit 41 and the thermal runaway suppression fault bit 42 can be specifically set to a sound alarm or an indicator light alarm or a combination of the two; at the same time, the vehicle terminal 5 can also transmit the thermal runaway information to the vehicle monitoring platform 20 and the mobile terminal 21 through the wireless network 19, thereby strengthening the safety monitoring of electric vehicles.

[0070] The present invention firstly sets a thermal runaway warning unit 9 and a battery management unit 8 inside the power battery 2, which are used to monitor the parameters such as the concentration of combustible gas, temperature, voltage of a single cell or the smallest parallel unit inside the battery pack. Before thermal runaway occurs, the temperature and pressure inside the single cell increase to activate the pressure relief valve, thereby causing a sudden increase in the concentration of combustible gas inside the power battery 2, a sudden rise in temperature, a sudden drop in the voltage of the single cell, and a sudden drop in the pressure difference of the single cell; the two parameters of the sudden increase in the concentration of combustible gas and the sudden rise in temperature in the battery pack can be obtained by the sensors set by the thermal runaway warning unit 9 and the battery management unit 8, and the sensors include combustible gas Concentration sensor 12, temperature sensing cable 13 or temperature sensor, namely temperature acquisition module 83; the two parameters of single cell voltage drop and single cell pressure difference drop can be acquired by battery management unit 8 and transmitted to suppression controller 17 of thermal runaway warning unit 9 via CAN bus; thermal runaway warning unit 9 and battery management unit 8 transmit thermal runaway related parameters to vehicle controller 3 and instrument 4 via CAN bus; the instrument displays its parameter value or fault value in real time, so that the driver can understand the battery safety in time; the vehicle controller 3 sends corresponding instructions to each component system of the vehicle according to the specific parameter value.

[0071] Secondly, the thermal runaway suppression unit 6 mainly includes a fire extinguishing agent 15, an injector 16, a fire extinguishing agent delivery pipe 11, and a suppression controller 17. The suppression controller 17 receives information from the thermal runaway warning unit 9 and the battery management unit 8 through the CAN bus. When a certain monitoring value threshold is reached, the injector 16 is opened, and the fire extinguishing agent 15 is sprayed into the power battery 2 at a certain speed through the fire extinguishing agent delivery pipe 11 to suppress the expansion of thermal runaway; according to the installation space requirements, the fire extinguishing agent 15 and the injector 16 can also be integrated into one and installed inside the power battery; at the same time, the start-up fire extinguishing agent state quantity is transmitted to the vehicle controller 3 and the instrument 4 through the CAN bus; the instrument 4 displays its parameter value or fault value in real time, so that the driver can promptly understand whether the battery fire extinguishing has been triggered; if the triggered information is received, the vehicle controller 3 executes the highest level fault action, including speed limit driving, high voltage delayed power-off, etc., to prevent the expansion of danger.

[0072] At the same time, the vehicle-mounted terminal 5 obtains the relevant information of the CAN bus thermal runaway warning unit 9 and the thermal runaway suppression unit 6 in real time, combines the positioning information of the GPS module 31, and finally transmits the thermal runaway information to the vehicle monitoring platform 20 or the mobile terminal 21 through the wireless network 19. It can remotely and timely understand the safety information of the electric vehicle, which helps to reduce and avoid vehicle fire incidents.

[0073] When the electric vehicle is in driving state, the thermal runaway warning method of the present invention is as follows: Figure 4As shown, 1) the battery management unit 8 and the thermal runaway warning unit 9 send information to the vehicle controller 3 through the CAN line, and the vehicle controller 3 determines whether the parameters related to thermal runaway (including single cell voltage, single cell pressure difference, single cell temperature, temperature sensing cable on / off, ambient temperature, single cell temperature change rate, ambient temperature change rate, and combustible gas concentration) are normal; 2) If normal, continue driving; 3) If any parameter value is abnormal, including the combustible gas CO concentration greater than 300ppm, the single cell temperature rise greater than 10℃ / 10s, and the temperature sensing cable is triggered, (this embodiment is specifically explained by the abnormal parameters of a certain brand of power battery: the single cell voltage is lower than 2.8V or higher than 4.2V, the single cell pressure difference is greater than 500mV, and the single cell temperature is greater than 10℃ / 10s. Or the ambient temperature is higher than 55°C, the temperature difference of a single cell is greater than 15°C, the temperature difference is greater than 10°C / 10s, the total power SOC of the battery pack is greater than 100%, and the insulation value of the battery pack is less than 200kΩ, and the numerical settings of the above fault thresholds are specifically provided by a certain battery brand), then the automobile controller 3 sends the following instructions at the same time: the thermal runaway suppression unit 6 starts to spray the fire extinguishing agent, drives at a limited speed, delays 30s to cut off the high voltage, the instrument 4 displays a thermal runaway warning fault alarm, the automobile monitoring platform 20 displays a thermal runaway warning fault alarm, and the mobile terminal 21 displays a thermal runaway warning fault alarm; 4) The automobile controller 3 sends fault information: the automobile monitoring platform 20 shows that the fire extinguishing agent has been sprayed, the mobile terminal 21 shows that the fire extinguishing agent has been sprayed, the car stops, and cannot be powered on again.

[0074] When the electric vehicle is in charging state, the thermal runaway warning method of the present invention is as follows: Figure 5As shown, 1) the single cell management unit 8 and the thermal runaway warning unit 9 send information to the vehicle controller 3 through the CAN line, and the vehicle controller 3 determines whether the parameters related to thermal runaway (including single cell voltage, single cell pressure difference, single cell temperature, ambient temperature, temperature sensing cable on / off, single cell temperature change rate, ambient temperature change rate, and combustible gas concentration) are normal; 2) If normal, continue charging; 3) If any parameter value is abnormal, including the combustible gas CO concentration greater than 300ppm, the single cell temperature rise greater than 10℃ / 10s, and the temperature sensing cable is triggered, (this embodiment is specifically explained by the abnormal parameters of a certain brand of power battery: the single cell voltage is lower than 2.8V or higher than 4.2V, ... The battery pressure difference is greater than 500mV, the single cell temperature or the ambient temperature is higher than 55℃, the single cell temperature difference is greater than 15℃, the temperature difference is greater than 10℃ / 10s, the total battery capacity SOC of the battery pack is greater than 100%, and the battery pack insulation value is less than 200kΩ. The numerical settings of the above fault thresholds are specifically provided by a certain battery brand). Then the automobile controller 3 sends the following instructions at the same time: the thermal runaway suppression unit 6 starts to spray the fire extinguishing agent, cuts off the charging, the automobile monitoring platform 20 displays the thermal runaway warning fault alarm, and the mobile terminal 21 displays the thermal runaway warning fault alarm; 4) The automobile controller 3 sends fault information: the automobile monitoring platform 20 shows that the fire extinguishing agent has been sprayed, the mobile terminal 21 shows that the fire extinguishing agent has been sprayed, and the car cannot be powered on.

[0075] When the electric vehicle is stopped, the thermal runaway warning method of the present invention is as follows: Figure 6 As shown, 1) the single cell management unit 8 and the thermal runaway warning unit 9 send information to the vehicle controller 3 through the CAN line, and the vehicle controller 3 determines whether the parameters related to thermal runaway (including single cell voltage, single cell pressure difference, single cell temperature, ambient temperature, temperature sensing cable on / off, single cell temperature change rate, ambient temperature change rate, and combustible gas concentration) are normal; 2) If normal, the vehicle stops normally; 3) If any parameter value is abnormal, including the combustible gas CO concentration greater than 300ppm, the single cell temperature rise greater than 10℃ / 10s, and the temperature sensing cable is triggered, (this embodiment is specifically explained by the abnormal parameters of a certain brand of power battery: the single cell voltage is lower than 2.8V or higher than 4.2 V, single cell pressure difference is greater than 500mV, single cell temperature or ambient temperature is higher than 55℃, single cell temperature difference is greater than 15℃, temperature difference is greater than 10℃ / 10s, total battery pack SOC is greater than 100%, battery pack insulation value is less than 200kΩ, the numerical settings of the above fault thresholds are specifically provided by a certain battery brand), then the automobile controller 3 sends the following instructions at the same time: the thermal runaway suppression unit 6 starts to spray the fire extinguishing agent, the automobile monitoring platform 20 displays the thermal runaway warning fault alarm, and the mobile terminal 21 displays the thermal runaway warning fault alarm; 4) the automobile controller 3 sends fault information: the automobile monitoring platform 20 shows that the fire extinguishing agent has been sprayed, the mobile terminal 21 shows that the fire extinguishing agent has been sprayed, and the automobile cannot be powered on.

[0076] At present, electric vehicle fires often lack thermal runaway warning and suppression functions, and thermal runaway cannot be suppressed in the early stage, resulting in the spread of danger and battery pack fire, which ultimately requires manual external fire extinguishing. The present invention analyzes the necessary factors that lead to fire before thermal runaway occurs, such as combustible gas concentration, temperature, etc., and the thermal runaway warning unit 9 and the battery management unit 8 collect relevant physical quantities. The vehicle controller 3 summarizes the parameters provided by the thermal runaway warning unit 9 and the battery management unit 8, and determines the comprehensive index of thermal runaway occurrence. For parameters that deviate from normal values, an instruction is immediately sent to the thermal runaway suppression unit 6 to start spraying fire extinguishing agents, dilute the combustible gas concentration, reduce the temperature in the battery pack, eliminate combustion free radicals, and suppress the occurrence and spread of thermal runaway. From the time dimension, the occurrence of battery fires is reduced; the thermal runaway warning unit 9 and the thermal runaway suppression unit 6 can send their relevant information to the instrument 4 in the cab through the CAN line, and transmit the danger information to the driver in time to reduce possible casualties; the vehicle controller 3 can extract thermal runaway related parameter information, make timely adjustments to the vehicle parameters, and prevent human factors from exacerbating battery fire events; the vehicle terminal 5 collects relevant thermal runaway information through the CAN line, and transmits it to the vehicle monitoring platform 20 and the mobile terminal 21 through the wireless network 19. Even if the electric vehicle is parked, real-time monitoring can be achieved to reduce and avoid casualties and property losses around the electric vehicle when danger occurs; the present invention establishes a multi-dimensional connection network between thermal runaway related information and the driver, the vehicle monitoring platform 20, the owner, etc., which can effectively reduce the risk of battery fire and vehicle burning; the present invention is applicable to the driving, parking, and charging states of the vehicle. Through the joint control of thermal runaway information by the vehicle monitoring platform 20 and the mobile terminal 21, the probability of battery fire is especially reduced when the vehicle is unattended, including the parking and charging states.

[0077] The specific models of the components used in the present invention are as follows: the model used by the vehicle controller 3 is VCU20100-S; the chip model used by the early warning controller 14 and the suppression controller 17 is STM32F103; the model used by the power battery 2 is ev-pb03, and the model used by the battery controller 81 is bms-cg03; the model used by the vehicle terminal 5 is V600; the model of the combustible gas sensor 12 is MQ-K5; the temperature sensing cable 13 selects NTC thermistor insulation material and the trigger temperature is 105°C; the model of the AD conversion module 18 is MCP3424; the model of the voltage acquisition module 82 is SC-ACEP02-V12-R; the model of the temperature acquisition module 83 is ADAM-3600; the model of the GPS module 31 is SKG12Q; the model of the vehicle speed sensor 32 is DJS-1.

[0078] What needs to be explained about the specific structure of the present invention is that the connection relationship between the various component modules adopted in the present invention is definite and feasible. Except for the special instructions in the embodiments, the specific connection relationship can bring about the corresponding technical effects and solve the technical problems raised by the present invention without relying on the execution of the corresponding software program. Except for the specific instructions, the models and connection methods of the components, modules and specific components appearing in the present invention belong to the existing technologies such as published patents, published journal articles or common knowledge that can be obtained by technical personnel in this field before the application date, and there is no need to elaborate, so that the technical solution provided in this case is clear, complete and feasible, and the corresponding physical products can be reproduced or obtained according to the technical means.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A thermal runaway warning and suppression control method for electric vehicles, characterized in that: An electric vehicle thermal runaway warning and suppression system is used, the system comprising an electric vehicle body (1), the electric vehicle body (1) comprising a power battery (2) and an automobile controller (3); A thermal runaway suppression unit (6) is arranged outside the power battery (2), and a battery module (7), a battery management unit (8), and a thermal runaway warning unit (9) are arranged inside the power battery (2); The thermal runaway suppression unit (6) comprises a fire extinguishing agent (15), an injector (16), and a suppression controller (17); the injector (16) is arranged at the output end of the fire extinguishing agent (15); the injector (16) is connected to a fire extinguishing agent nozzle (10) via a fire extinguishing agent transmission pipeline (11); and the fire extinguishing agent nozzle (10) is arranged inside the power battery (2); The battery management unit (8) comprises a battery controller (81), a voltage acquisition module (82) and a temperature acquisition module (83), wherein the voltage acquisition module (82) and the temperature acquisition module (83) are arranged around a single cell inside the power battery (2); The thermal runaway warning unit (9) comprises a combustible gas concentration sensor (12), a temperature sensing cable (13), and a warning controller (14); the combustible gas concentration sensor (12) and the temperature sensing cable (13) are arranged inside the power battery (2); The vehicle controller (3) is connected to the warning controller (14), the suppression controller (17), and the battery controller (81) respectively through wires, and the signal output end of the combustible gas concentration sensor (12) and the signal control end of the temperature sensing cable (13) are connected to the warning controller (14) through an AD conversion module (18); The suppression controller (17) is connected to the control end of the injector (16) via a wire, and is used to control the injector (16) to open or close the fire extinguishing agent nozzle (10); The driving compartment of the electric vehicle body (1) is provided with an instrument (4) and an on-board terminal (5); The instrument (4) is provided with a thermal runaway warning fault position (41) and a thermal runaway suppression fault position (42); The vehicle controller (2) is also connected to the instrument (4) and the vehicle terminal (5) respectively through wires, and the vehicle terminal (5) is wirelessly connected to the vehicle monitoring platform (20) and the mobile terminal (21) through a wireless network (19); The battery controller (81) is connected to a voltage acquisition module (82) and a temperature acquisition module (83) respectively through wires, wherein the voltage acquisition module (82) is used to acquire voltage data of a power battery cell or a minimum parallel unit, and the temperature acquisition module (83) is used to acquire temperature data of a power battery cell; The vehicle controller (3) is also connected to a GPS module (31) via a wire, and is used to obtain real-time location information of the electric vehicle body (1); The vehicle controller (3) is also connected to a vehicle speed sensor (32) via a wire; The method comprises the following steps: Step 1: controlling the vehicle speed sensor (32) to collect data and send it to the vehicle controller (3), controlling the battery management unit (8) and the thermal runaway warning unit (9) to collect thermal runaway data and send it to the vehicle controller (3), wherein the thermal runaway data includes voltage data of a single cell or a minimum parallel unit of the power battery (2), temperature data of a single cell, ambient temperature data, and combustible gas concentration data; Step 2: The vehicle controller (3) analyzes and processes the vehicle speed data collected by the vehicle speed sensor (32), and the steps are as follows: Step 2.1: When the data of the vehicle speed sensor (32) is continuously 0, it is determined that the electric vehicle body (1) is in a stopped state, and the process proceeds to step 3; Step 2.2: When the data of the vehicle speed sensor (32) is greater than 0, it is determined that the electric vehicle body (1) is in a driving state, and the process proceeds to step 4; Step 2.3: when it is determined through step 2.1 that the electric vehicle body (1) is in a stopped state and the power battery (2) is detected to be in a charging state, the process proceeds to step five; Step 3: The vehicle controller (3) performs threshold judgment on the thermal runaway data. When the thermal runaway data is within the normal threshold, the electric vehicle body (1) stops driving normally. When any thermal runaway data exceeds the normal threshold, including the combustible gas CO concentration being greater than 300ppm, the single cell temperature rise being greater than 10°C / 10s, and the temperature sensing cable being triggered, the vehicle controller (3) executes the abnormal state instruction 1 and sends the fault information 1 to the vehicle monitoring platform (20) and the mobile terminal (21); Step 4: The vehicle controller (3) performs threshold judgment on the thermal runaway data. When the thermal runaway data is within the normal threshold, the electric vehicle body (1) continues to drive. When any thermal runaway data exceeds the normal threshold, including the combustible gas CO concentration being greater than 300ppm, the single cell temperature rise being greater than 10°C / 10s, and the temperature sensing cable being triggered, the vehicle controller (3) executes the state abnormality instruction 2 and sends the fault information 2 to the vehicle monitoring platform (20) and the mobile terminal (21); Step 5: The vehicle controller (3) performs threshold judgment on the thermal runaway data. When the thermal runaway data is within the normal threshold, the battery continues to charge. When any thermal runaway data exceeds the normal threshold, including the combustible gas CO concentration greater than 300ppm, the single cell temperature rise greater than 10°C / 10s, and the temperature sensing cable is triggered, the vehicle controller (3) executes the state abnormality instruction three and sends the fault information one to the vehicle monitoring platform (20) and the mobile terminal (21); The execution state abnormal instruction 1 in step 3 is specifically: firstly, the controller (17) is inhibited from controlling the injector (16) to start and inject the fire extinguishing agent into the power battery (2); secondly, the vehicle monitoring platform (20) displays a thermal runaway warning fault; and finally, the mobile terminal (21) displays a thermal runaway warning fault; the fault information 1 includes that the vehicle monitoring platform (20) displays that the fire extinguishing agent has been injected, the mobile terminal (21) displays that the fire extinguishing agent has been injected, and at the same time, the vehicle controller (3) controls the vehicle to be unable to be powered on; The execution state abnormal instruction 2 in step 4 is specifically as follows: first, the vehicle controller (2) controls the thermal runaway warning fault position (41) on the instrument (4) to give an alarm prompt, and at the same time controls the electric vehicle body (1) to travel at a limited speed, the vehicle monitoring platform (20) to display a thermal runaway warning fault, the mobile terminal (21) to display a thermal runaway warning fault, and delays cutting off the high voltage of the vehicle for a period of time, and then the suppression controller (17) controls the injector (16) to start and inject the fire extinguishing agent into the power battery (2); The second fault information includes that the vehicle monitoring platform (20) displays that the fire extinguishing agent has been sprayed, the mobile terminal (21) displays that the fire extinguishing agent has been sprayed, and at the same time the vehicle controller (3) controls the vehicle to drive at a limited speed and quickly stop driving, and the vehicle cannot be powered on again; The execution status abnormal instruction three in step five is specifically as follows: firstly, the charging battery switch is cut off, and at the same time, the controller (17) is inhibited from controlling the injector (16) to start and inject the fire extinguishing agent into the power battery (2); secondly, the vehicle monitoring platform (20) displays a thermal runaway warning fault; and finally, the mobile terminal (21) displays a thermal runaway warning fault.

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