Electric motor coach power battery fire prevention and control method
By designing a four-level fire determination and treatment mechanism and an independently operated fire extinguishing controller in electric buses, combining the electric drive cooling system and the battery water cooling system, the fire prevention and control problems in the existing technology when the vehicle control system fails. Accurate fire prevention and control and fire suppression effects.
Patent Information
- Application Number
- CN202410912560.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-09
- Publication Date
- 2024-12-13
AI Technical Summary
The existing electric bus power battery fire prevention and control technology cannot work independently when the vehicle control system fails, the fire extinguishing system cannot operate normally, and the fire situation cannot be further suppressed after the fire extinguishing agent is exhausted, which poses a safety hazard.
A fire prevention and control method for electric passenger vehicle power battery including power battery packs, solenoid valves, fire extinguishing devices, monitors, fire extinguishing controllers and vehicle cooling systems has been designed. Through the four-level fire judgment and treatment mechanism, the fire extinguishing controller can Operate independently, use the electric drive cooling system and battery water cooling system to pump coolant to suppress fires, ensuring that fires can still be effectively prevented and controlled when the vehicle is stopped or the power supply fails.
It realizes independent fire extinguishing capabilities when the vehicle power supply or controller fails, with accurate prevention and control effects, and continues to pump coolant through the water tank after the fire extinguishing agent is exhausted to suppress the fire, improving the fire safety of electric buses.
Smart Images
Figure CN119133662A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of electric buses, and in particular relates to a method for preventing and controlling fires of power batteries of electric buses. Background Art
[0002] Electric buses have a large installed capacity of power batteries. As a means of public transportation, they carry a large number of passengers. When the power batteries suffer thermal runaway, the safety risk is very high. Electric buses have higher requirements for fire prevention and control of power batteries.
[0003] At present, most technical solutions rely on the coordinated work of the vehicle control system and the battery fire extinguishing system. When a vehicle fire occurs and the vehicle control system fails, the battery fire extinguishing system cannot complete the fire extinguishing work well or even cannot work normally. When the fire extinguishing agent of the battery fire extinguishing system is exhausted, there is no way to control the subsequent fire. The current technical solutions have many deficiencies.
[0004] For example, a Chinese invention patent (publication number: CN 113694433 A) discloses a power battery fire extinguishing system and a power battery fire extinguishing method. The system includes a power battery pack, at least one thermal runaway detector, at least one fire extinguishing agent storage tank, a vehicle controller and a fire extinguisher controller. The thermal runaway detector is used to detect the thermal runaway signal in the battery pack and send the thermal runaway signal to the vehicle controller. The vehicle controller sends a fire extinguishing instruction to the fire extinguisher controller, and then controls the fire extinguishing agent storage tank to spray the fire extinguishing agent into the power battery pack. This can realize automatic detection of thermal runaway of the power battery pack in the electric vehicle, as well as fire extinguishing and cooling.
[0005] The above technical scheme also has the following defects: The fire extinguishing command is sent by the vehicle controller. When the vehicle controller fails, the fire extinguishing system cannot work. In order to ensure the fire extinguishing effect, the scheme requires the vehicle to be equipped with multiple fire extinguishing agent storage tanks, which increases the difficulty of vehicle layout and vehicle manufacturing cost. It does not have the functions of remote wake-up and self-wake-up. After the vehicle is parked, the fire extinguishing system cannot enter the working mode and cannot cope with the situation where the vehicle power battery catches fire after parking. After the fire extinguishing agent is exhausted, there is no way to continue to cool the battery and release energy, and the vehicle can only wait for it to burn. Summary of the invention
[0006] The object of the present invention is to provide a method for preventing and controlling fires of power batteries of electric buses, so as to solve the problems raised in the above-mentioned background technology.
[0007] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a method for preventing and controlling fires of power batteries of electric buses, comprising at least one power battery pack, at least two solenoid valves, one power battery fire extinguishing device, several air pipes, a control harness, a power battery fire extinguishing device, and a whole vehicle cooling system, wherein the power battery pack is fixed on the vehicle, and each power battery pack shell is provided with one fire extinguishing nozzle and one pressure relief valve, and the power battery pack is provided with one monitor, and the power battery fire extinguishing device contains one fire extinguishing agent storage tank, one fire extinguishing controller, one battery, and one PWM water pump, and the whole vehicle cooling system contains an electric drive cooling system and a battery water cooling system, and both the electric drive cooling system and the battery water cooling system contain a water supply tank, and the battery fire extinguishing device, the power battery pack, and the whole vehicle cooling system are connected by air pipes, and the monitor and the fire extinguishing controller are connected to the vehicle-mounted TBOX by harnesses.
[0008] Preferably, the method comprises the following steps: S1: Fire extinguishing controller wakes up; S2: The fire extinguishing controller wakes up the monitor in the battery pack, and the monitor detects and reports the CO, smoke, and temperature information of the battery pack; S3: The fire extinguishing controller detects and determines whether the CO content in the battery pack exceeds the standard; S4: If it is determined that the CO content is not exceeded, wait for the vehicle-mounted TBOX to send a wake-up command to the fire extinguishing controller or for the fire extinguishing controller to automatically wake up; S5: If it is determined that the CO content exceeds the standard, the fire extinguishing controller enters the fire level 1 judgment and processing mechanism; S6: The fire extinguishing controller enters the fast calculation working state, and the monitoring device reports the message cycle shortened; S7: If the smoke volume or the temperature inside the battery pack does not exceed the standard, return to step S6; S8: If the smoke volume exceeds the standard but not seriously exceeds the standard or the temperature in the battery pack exceeds the standard but not seriously exceeds the standard, the fire extinguishing controller determines that it is a level 2 (medium) fire, and the fire extinguishing controller sends a fire alarm request to the vehicle, and the fire extinguishing controller sends a control command to cool the battery water cooling system; S9: If the smoke volume seriously exceeds the standard, or the temperature in the battery pack seriously exceeds the standard, or the carbon monoxide content exceeds the standard and the rising rate is abnormal, the fire extinguishing controller determines that the fire is level 3 (serious). The fire extinguishing controller sends a fire sound and light alarm request to the whole vehicle, and the fire extinguishing controller controls the opening of the solenoid valve on the fire battery pack pipeline, and controls the water pump to run at a low speed to pump the fire extinguishing agent into the battery pack that reports the fire; S10: If the fire of level 3 lasts for more than 3 minutes or the fire extinguishing agent has been completely pumped out or the battery pack monitor that reports the fire has been disconnected, the fire extinguishing controller determines that the fire is level 4 (the most serious), and the fire extinguishing controller sends an urgent fire sound and light alarm request to the whole vehicle, and the fire extinguishing controller controls the solenoid valve of the whole vehicle cooling system to open, and the fire extinguishing controller controls the water pump to run at high speed, and pumps the remaining fire extinguishing agent, the low-temperature coolant in the battery water cooling system, and the coolant in the electric drive cooling system into the fire battery pack; S11: If the fire of level 3 does not last for more than 3 minutes or the fire extinguishing agent has been completely pumped out or the battery pack monitor that reports the fire has been disconnected, then return to step S8; S12: End.
[0009] Preferably, the fire extinguishing agent liquid is a perfluorohexanone solution with a molar concentration exceeding 95%, and the battery uses a 12V safety voltage and a lithium iron phosphate battery material.
[0010] Preferably, a battery is provided, and the fire extinguishing controller can operate independently without the need for the entire vehicle to provide it with power and control information. After the vehicle is powered off due to a fire or the vehicle is parked and powered off, the fire extinguishing controller can still operate normally.
[0011] Preferably, it is divided into 4 levels of fire alarm, and corresponding fire prevention and control are carried out according to different fire levels. Preferably, the fire extinguishing controller is provided with a timer, which enters a low power consumption state after dormancy and automatically wakes up once every 6 hours Preferably, when the fire extinguishing agent and coolant are exhausted, water or fire extinguishing agent can be added to the water tank of the vehicle cooling system to continue to extinguish the battery fire.
[0012] Technical effects and advantages of the present invention: The present invention solves the problems of inaccurate early warning, false triggering of fire extinguishing system, non-universal system parameters and inability to realize platformization, etc. in the method of commonly using CO content as the core indicator of fire early warning in the industry.
[0013] The power battery fire prevention and control method developed by the present invention adopts a four-level fire prevention and control mechanism, and has precise prevention and control effects.
[0014] The present invention does not completely rely on the whole vehicle to provide power, and does not rely on the whole vehicle control to achieve fire extinguishing. When the vehicle power supply or vehicle controller fails, it can still operate independently to extinguish the fire.
[0015] When the fire extinguishing medium stored in the power battery fire extinguishing device is exhausted, all the coolant in the vehicle's cooling system can be pumped into the battery pack to maximize energy release and fire suppression. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 It is a schematic diagram of the present invention; Figure 2 The present invention is a flow chart of the fire prevention and control method. DETAILED DESCRIPTION
[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0018] The present invention provides Figure 1-2 A method for preventing and controlling power battery fires in electric buses is shown, comprising at least one power battery pack, at least two solenoid valves, one power battery fire extinguishing device, several air pipes, a control harness, a power battery fire extinguishing device, and a whole vehicle cooling system. The power battery pack is fixed on the vehicle, and each power battery pack shell is equipped with a fire extinguishing nozzle and a pressure relief valve. A monitor is installed inside the power battery pack. The power battery fire extinguishing device contains a fire extinguishing agent storage tank, a fire extinguishing controller, a battery, and a PWM water pump. The whole vehicle cooling system includes an electric drive cooling system and a battery water cooling system. Both the electric drive cooling system and the battery water cooling system include a water supply tank. The battery fire extinguishing device, the power battery pack, and the whole vehicle cooling system are connected by air pipes, and the monitor and the fire extinguishing controller are connected to the vehicle-mounted TBOX through a harness.
[0019] Specifically, a method for preventing and controlling fire of a power battery of an electric bus comprises the following steps: S1: Fire extinguishing controller wakes up; S2: The fire extinguishing controller wakes up the monitor in the battery pack, and the monitor detects and reports the CO, smoke, and temperature information of the battery pack; S3: The fire extinguishing controller detects and determines whether the CO content in the battery pack exceeds the standard; S4: If it is determined that the CO content is not exceeded, wait for the vehicle-mounted TBOX to send a wake-up command to the fire extinguishing controller or for the fire extinguishing controller to automatically wake up; S5: If it is determined that the CO content exceeds the standard, the fire extinguishing controller enters the fire level 1 judgment and processing mechanism; S6: The fire extinguishing controller enters the fast calculation working state, and the monitoring device reports the message cycle shortened; S7: If the smoke volume or the temperature inside the battery pack does not exceed the standard, return to step S6; S8: If the smoke volume exceeds the standard but not seriously exceeds the standard or the temperature in the battery pack exceeds the standard but not seriously exceeds the standard, the fire extinguishing controller determines that it is a level 2 (medium) fire, and the fire extinguishing controller sends a fire alarm request to the vehicle, and the fire extinguishing controller sends a control command to cool the battery water cooling system; S9: If the smoke volume seriously exceeds the standard, or the temperature in the battery pack seriously exceeds the standard, or the carbon monoxide content exceeds the standard and the rising rate is abnormal, the fire extinguishing controller determines that the fire is level 3 (serious). The fire extinguishing controller sends a fire sound and light alarm request to the whole vehicle, and the fire extinguishing controller controls the opening of the solenoid valve on the fire battery pack pipeline, and controls the water pump to run at a low speed to pump the fire extinguishing agent into the battery pack that reports the fire; S10: If the fire of level 3 lasts for more than 3 minutes or the fire extinguishing agent has been completely pumped out or the battery pack monitor that reports the fire has been disconnected, the fire extinguishing controller determines that the fire is level 4 (the most serious), and the fire extinguishing controller sends an urgent fire sound and light alarm request to the whole vehicle, and the fire extinguishing controller controls the solenoid valve of the whole vehicle cooling system to open, and the fire extinguishing controller controls the water pump to run at high speed, and pumps the remaining fire extinguishing agent, the low-temperature coolant in the battery water cooling system, and the coolant in the electric drive cooling system into the fire battery pack; S11: If the fire of level 3 does not last for more than 3 minutes or the fire extinguishing agent has been completely pumped out or the battery pack monitor that reports the fire has been disconnected, then return to step S8; S12: End.
[0020] Specifically, the fire extinguishing agent liquid is a perfluorohexanone solution with a molar concentration exceeding 95%, and the battery uses a 12V safety voltage and a lithium iron phosphate battery material.
[0021] Specifically, a battery is provided, and the fire extinguishing controller can operate independently without the need for the entire vehicle to provide it with power and control information. After the vehicle is powered off due to a fire or the vehicle is parked and powered off, the fire extinguishing controller can still work normally.
[0022] Specifically, it is divided into 4 levels of fire alarm, and corresponding fire prevention and control are carried out according to different fire levels.
[0023] Specifically, the fire extinguishing controller is equipped with a timer, which enters a low power consumption state after dormancy and automatically wakes up once every 6 hours Specifically, when the fire extinguishing agent and coolant are exhausted, you can continue to extinguish the battery fire by adding water or fire extinguishing agent to the water tank of the vehicle's cooling system.
Claims
1. A method for preventing and controlling fires of power batteries in electric buses, characterized by: It includes at least one power battery pack, at least two solenoid valves, one power battery fire extinguishing device, several air pipes, a control wiring harness, a power battery fire extinguishing device, and a vehicle cooling system. The power battery pack is fixed on the vehicle. Each power battery pack shell is equipped with a fire extinguishing nozzle and a pressure relief valve. A monitor is installed inside the power battery pack. The power battery fire extinguishing device contains a fire extinguishing agent storage tank, a fire extinguishing controller, a battery, and a PWM water pump. The vehicle cooling system includes an electric drive cooling system and a battery water cooling system. The electric drive cooling system and the battery water cooling system both include a water supply tank. The battery fire extinguishing device, power battery pack, and vehicle cooling system are connected by air pipes. The monitor and fire extinguishing controller are connected to the vehicle-mounted TBOX through wiring harnesses.
2. The electric bus power battery fire prevention and control method according to claim 1, characterized in that: The following steps are involved: S1: Fire extinguishing controller wakes up; S2: The fire extinguishing controller wakes up the monitor in the battery pack, and the monitor detects and reports the battery pack CO, smoke, and temperature information; S3: The fire extinguishing controller detects and determines whether the CO content in the battery pack exceeds the standard; S4: If it is determined that the CO content is not exceeding the standard, wait for the vehicle-mounted TBOX to send a wake-up command to the fire extinguishing controller or for the fire extinguishing controller to automatically wake up; S5: If the CO content is determined to be excessive, the fire extinguishing controller enters the fire level 1 determination and processing mechanism; S6: The fire extinguishing controller enters the fast calculation working state, and the monitoring device reports the message cycle shortened; S7: If the amount of smoke or the temperature inside the battery pack does not exceed the standard, return to step S6; S8: If the smoke volume exceeds the standard but is not seriously exceeded, or the temperature inside the battery pack exceeds the standard but is not seriously exceeded, the fire extinguishing controller determines that it is a Level 2 (medium) fire. The fire extinguishing controller sends a fire alarm request to the entire vehicle and issues a control command to cool the battery water cooling system. S9: If the smoke volume seriously exceeds the standard, the temperature inside the battery pack seriously exceeds the standard, or the carbon monoxide content exceeds the standard and the rising rate is abnormal, the fire extinguishing controller determines that the fire is level 3 (serious). The fire extinguishing controller sends a fire sound and light alarm request to the entire vehicle. The fire extinguishing controller controls the opening of the solenoid valve on the fire battery pack pipeline and controls the PWM water pump to run at a low speed to pump the fire extinguishing agent into the fire-reported battery pack; S10: If a Level 3 fire persists for more than three minutes, the fire extinguishing agent has been completely pumped out, or the battery pack monitor reporting the fire has gone offline, the fire extinguishing controller determines the fire to be Level 4 (the most serious). The fire extinguishing controller issues an urgent fire alarm request to the entire vehicle, controls the solenoid valve of the vehicle's cooling system to open, and controls the PWM water pump to run at high speed to pump the remaining fire extinguishing agent, the low-temperature coolant in the battery water cooling system, and the coolant in the electric drive cooling system into the fire battery pack. S11: If the fire does not last for more than 3 minutes at level 3, or the fire extinguishing agent has been completely pumped out, or the battery pack monitor that reported the fire has been disconnected, then return to step S8; S12: End.
3. The electric bus power battery fire prevention and control method according to claim 1, characterized in that: The fire extinguishing agent liquid is a perfluorohexanone solution with a molar concentration exceeding 95%, and the battery uses a 12V safety voltage and lithium iron phosphate battery material.
4. The electric bus power battery fire prevention and control method according to claim 1, characterized in that: Equipped with a battery, the fire extinguishing controller can operate independently without the need for the entire vehicle to provide it with power and control information. After the vehicle is powered off due to a fire or the vehicle is parked and powered off, the fire extinguishing controller can still work normally.
5. The electric bus power battery fire prevention and control method according to claim 2, characterized in that: It is divided into 4 levels of fire alarm, and corresponding fire prevention and control measures are carried out for different fire levels.
6. The electric bus power battery fire prevention and control method according to claim 2, characterized in that: The fire extinguishing controller is provided with a timer, which enters a low power consumption state after dormancy and automatically wakes up once every 6 hours.
7. The electric bus power battery fire prevention and control method according to claim 2, characterized in that: When the fire extinguishing agent and coolant are used up, you can continue to extinguish the battery fire by adding water or fire extinguishing agent to the water tank of the vehicle's cooling system.