Device and method for inhibiting fire breakout of battery pack

Abstract

The invention relates to a device and a method for inhibiting fire breakout of a battery pack. The device comprises an efficient electro-optical conversion system, a spectrum regulation and control system, a receptor system, a light insulation system and a central control system, wherein the efficient electro-optical conversion system is configured to convert the electric energy stored in the battery pack into optical energy, so that the heat release rate, the total heat release amount and the combustion growth rate index during fire breakout are reduced. The invention also provides a method for inhibiting the fire of the battery pack.

Description

Technical Field

[0001] The present invention belongs to the field of devices that can quickly delay the fire time and fire speed of a battery pack and reduce the combustion intensity, and relates to a device and method for suppressing the fire of a battery pack. Background Art

[0002] The battery pack of an electric vehicle is the core energy storage unit of the entire vehicle. Its structural design directly impacts safety, energy density, and lifespan. It primarily consists of cells, modules, a battery management system (BMS), a thermal management system, a structural protection system, a high-voltage electrical system, and other auxiliary components. The cell is the core component of the battery pack, storing electrical energy. Common types include square aluminum shells, cylindrical, and soft packs. The mainstream material systems are lithium-ion (NCM / NCA / LFP) and lithium iron phosphate (LFP).

[0003] Although the battery pack uses a large number of devices to protect it from ignition and fire caused by impact, deformation, puncture, etc., accidents are still unavoidable. Electric vehicle fires are characterized by rapid ignition, fierce ignition, and difficulty in extinguishing. Professionally known as: fast deflagration (0-100% combustion takes only 30 seconds) and high risk of re-ignition (battery residual heat can reach several hours).

[0004] Although a battery pack without stored electrical energy can catch fire due to residual chemical activity or other factors that cause the negative copper current collector to dissolve, depositing and causing an internal short circuit, the intensity and speed of the fire are not sufficient to cause a sudden and serious danger. Therefore, the key to quickly reducing the time, speed, and intensity of a battery pack fire is to quickly convert the stored electrical energy into other forms of energy and safely and quickly release it to a safe distance. Summary of the Invention

[0005] This invention provides a device and method for suppressing battery pack fires. Research has revealed that the fastest energy conversion method is converting electrical energy into light energy, followed by plasma and arc, followed by mechanical energy, and finally thermal energy. Therefore, this invention prioritizes the conversion of electrical energy into light energy as its core technology and configuration. By converting the stored electrical energy in the battery pack into light energy as quickly and as extensively as possible, it reduces the rate and total amount of heat released during a battery pack fire, thereby lowering the combustion growth rate index.

[0006] The specific technical solutions are as follows:

[0007] A device for suppressing battery pack fire, comprising:

[0008] High-efficiency electro-optical conversion system, spectrum control system, sensor system, light isolation system and central control system;

[0009] The high-efficiency electro-optical conversion system is configured to convert the electrical energy stored in the battery pack into light energy to reduce the heat release rate, total heat release amount and combustion growth rate index during fire.

[0010] The high-efficiency electro-optical conversion system comprises:

[0011] High-power pulsed laser electro-optical conversion subsystem, configured in each battery pack;

[0012] The explosive wire electro-optical conversion subsystem is configured in each battery module;

[0013] The plasma arc electro-optical conversion subsystem wraps around the entire battery pack;

[0014] The triggering mode of the subsystem includes self-triggering or central control system command triggering;

[0015] The high-power pulse laser electro-optical conversion subsystem is a first-level trigger device with a response time of 1-100ns;

[0016] The exploding wire electro-optical conversion subsystem is a second-stage triggering device with a response time of 1-10 μs, which is triggered by the first stage via a photoconductive switch;

[0017] The plasma arc electro-optical conversion subsystem is the third-stage main discharge device, which is triggered by the second stage through the wire explosion device.

[0018] Furthermore, in the first stage → second stage → third stage triggering process of this system, the synchronization accuracy of the first stage and the second stage is ±1ns, and the synchronization of the second stage and the third stage must meet the peak moment of the exploding wire current matching the peak voltage of the main discharge module.

[0019] Furthermore, the plasma arc electro-optical conversion subsystem includes an arc direction control device, which keeps the arc away from the vehicle body by at least one of the following methods:

[0020] Electromagnetic field guidance, using the Lorentz force to deflect the plasma;

[0021] Gas dynamics control, supersonic gas flow confinement of plasma jet;

[0022] Optical guidance: laser pre-ionizes the air to form a low-resistance channel, guiding the arc to propagate along the optical path.

[0023] Furthermore, the arc direction control device shortens the discharge distance by power modulation or environmental medium regulation, satisfying the relationship:

[0024] Where P is power, τ is pulse width, ρ is air density, and Cp is specific heat capacity.

[0025] Furthermore, the sensor system includes the following sensors distributed in the battery cells, modules and compartments: power control sensors, pressure sensors, temperature sensors, position and displacement sensors, humidity sensors, spectrum and light intensity detectors, and flame color detectors; these sensors should be configured according to the battery cell position, battery module distribution, and each battery compartment to detect changes in parameters at each position.

[0026] Furthermore, the spectrum control system increases the energy proportion of the non-visible light band by adding metal vapor or filter structure to reduce damage to the organism.

[0027] Furthermore, the light isolation system includes:

[0028] Physical blocking devices;

[0029] Optical filtering device.

[0030] Furthermore, the physical shielding device includes an opaque or translucent material; and the optical filtering device includes a neutral density filter or a polarizing filter.

[0031] Furthermore, the central control system is configured as follows:

[0032] Assess the severity of the accident based on sensor data and choose to release all or part of the battery pack's power;

[0033] Control self-trigger or command trigger mode to avoid false triggering;

[0034] The system sends evacuation alarms and time limits to passengers inside the vehicle, and warns people outside the vehicle about arc hazard areas.

[0035] A method for suppressing battery pack fire as described above includes the following steps:

[0036] S1: Real-time monitoring of battery pack status parameters through the sensor system;

[0037] S2: When the central control system determines that the battery pack has a fire risk, it triggers the high-efficiency electro-optical conversion system to convert electrical energy into light energy;

[0038] S3: Adjust the output light spectrum through the spectrum control system to reduce damage to organisms;

[0039] S4: Block or filter strong light radiation through light isolation system.

[0040] Technical effect:

[0041] The present invention converts electrical energy into light energy at the initial stage of battery thermal runaway (in milliseconds) to actively suppress deflagration. This is achieved through a three-stage energy conversion technology, specifically: a first-stage pulsed laser system for fastest triggering, seizing the golden time window; a second-stage explosive wire system for high-power consumption of large amounts of electrical energy; and a third-stage plasma arc system for complete elimination of residual electrical energy. Regarding synchronization control accuracy, the laser → explosive wire synchronization error is ≤±1ns (photoconductive switch control) to avoid energy transfer losses; and the explosive wire → arc current / voltage peak matching accuracy is ≤0.1μs to ensure the stability of the main discharge. Regarding directional and safe release, arc direction control keeps more than 90% of the energy away from the vehicle body (triple protection of electromagnetic field / gas dynamics / optical guidance); and the arc distance is shortened by 40-60% (through power modulation and gas filling optimization formulas). At the same time, the spectrum control system reduces the proportion of visible light to below 30% (by increasing the ultraviolet and infrared bands) to prevent retinal damage. The central control system has a false positive rate of less than 0.1% (multi-sensor fusion analysis: electrical, mechanical, optical, and thermal parameters). This has created an "energy bomb disposal system" for battery thermal runaway, providing a disruptive solution for electric vehicle safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a schematic diagram of the technical principle of the present invention. DETAILED DESCRIPTION

[0043] The present invention is described in detail below with reference to the various embodiments shown in the accompanying drawings, but it should be noted that these embodiments are not limitations of the present invention, and any equivalent transformations or substitutions in functions, methods, or structures made by ordinary technicians in this field based on these embodiments are all within the scope of protection of the present invention.

[0044] A novel device developed by integrating multiple technologies and facilities to rapidly delay the onset and speed of a battery pack fire, reducing its intensity. By converting the battery pack's stored electrical energy into light energy as quickly and as extensively as possible, this device reduces the rate and total amount of heat released during a battery pack fire, ultimately lowering the combustion growth rate exponential.

[0045] The battery pack of an electric vehicle is the core energy storage unit of the entire vehicle, and its structural design directly affects safety, energy density, and lifespan. It typically consists of cells, modules, a battery management system (BMS), a thermal management system, a structural protection system, a high-voltage electrical system, and other auxiliary components. The various components of this patented system are distributed according to the battery pack's configuration.

[0046] The device includes (1) a high-efficiency electro-optical conversion system, (2) a spectrum control system, (3) a sensor system, (4) a light isolation system, and (5) a central control system.

[0047] The high-efficiency electro-optical conversion system consists of the following subsystems: ① high-power pulse laser electro-optical conversion system, ② exploding wire electro-optical conversion system, and ③ plasma arc electro-optical conversion system.

[0048] Each battery pack is equipped with ① a high-power pulsed laser electro-optical conversion system, each battery module is equipped with ② an explosive wire electro-optical conversion system, and the entire battery pack is surrounded by ③ a plasma arc electro-optical conversion system. If a separate battery pack is used, the configuration is the same. Each of these high-efficiency electro-optical conversion system's subsystems is composed of numerous small units, and they can be triggered in two modes: self-triggering and triggering by command from the central control system.

[0049] Self-triggering is when the integrity of the subsystems of these (1) high-efficiency electro-optical conversion systems is destroyed, it triggers the start-up without relying on external instructions, and converts the energy of the connected battery components into light energy in the shortest possible time for release. This function is mainly used to activate the response plan as quickly as possible in the event of an accident, reducing the risk of battery explosion.

[0050] The central control system command triggering mode means that after the vehicle encounters an emergency, the battery components have been damaged, and some of the subsystems of the (1) high-efficiency electro-optical conversion system have been triggered and started, the (5) central control system will evaluate the severity of the current accident and determine whether it is necessary to release all the power of the battery components destructively and at one time, or, when the accident is minor and the damage is not serious, only release the power of part of the battery components to control the integrity of the battery components and reduce vehicle losses.

[0051] The first stage of the system's operation is triggered by a high-power pulsed laser electro-optical conversion system (①); the second stage, the exploding wire electro-optical conversion system (②), amplifies the released energy level; and the third stage, the plasma arc electro-optical conversion system, serves as the main discharge. The device that triggers the second stage is a photoconductive switch (GaAs PCSS), while the device that triggers the third stage is a wire explosion device. Triggering and initiation require A. laser-exploding wire synchronization and B. exploding wire-arc synchronization.

[0052] High-power pulsed laser electro-optical conversion systems offer the fastest response speed, reaching nanoseconds (1-100ns), and are the first to trigger operation. They utilize a rapid electrical discharge to excite an inert gas (such as xenon) or a laser medium (such as Nd:YAG) to generate intense light (including invisible light) or laser light. The greatest advantage of this system is its rapid response, allowing it to utilize Q-switched lasers. Currently, it is primarily used in industrial laser cutting and high-speed photography flashes, with electro-optical conversion efficiencies reaching 10-30% (laser diodes can achieve over 40%). Other methods for converting light energy into other electromagnetic energy include the X-ray photoelectric effect, which utilizes ultrashort laser pulses to excite a photocathode (such as Cs□Te) to generate femtosecond X-ray pulses (e.g., a free electron laser). However, the associated equipment is currently complex and bulky, making it unsuitable for integration into this patented system. However, its high energy release and rapid release rate make it a viable option for future applications once the technology matures. In this system, the high-power pulsed laser electro-optical conversion system (①) converts current industrial applications into rapid electrical energy release. In view of its ultra-fast triggering characteristics, it is used as the first-level triggering device in this subsystem.

[0053] After the high-power pulsed laser electro-optical conversion system (①) is triggered, the photoconductive switch (GaAs PCSS) converts the laser signal into a high-voltage electrical pulse to trigger the second-stage exploding wire electro-optical conversion system (②). This trigger switch is used because laser triggering minimizes circuit delays.

[0054] The exploding wire electro-optical conversion system, with a slightly slower response speed than the high-power pulsed laser electro-optical conversion system (①), exhibits a microsecond (1-10μs) burst, serving as a secondary triggering device. When a high voltage and high current pass through a metal wire (such as tungsten), it instantly vaporizes and generates plasma light, thereby consuming electrical energy. While the electro-optical conversion efficiency is somewhat lower, at approximately 5-15%, the energy density is extremely high, with optical output power reaching gigawatt levels. This significantly reduces the battery pack's capacity.

[0055] The reason for using a wire explosion device to trigger the third stage is also to minimize circuit delays: the wire is triggered by laser to cause explosion, breaking through the gas to form a plasma channel.

[0056] The plasma arc electro-optical conversion system's greatest advantage lies in its sustained discharge, serving as the third stage of the system's main discharge. It generates an arc plasma (temperature 5000-20000K) by breaking down a gas at high voltage. The breakdown time is approximately 0.1-1μs, and the sustained discharge is controllable. The electro-optical conversion efficiency is approximately 20-35% (including UV to visible light), but the cumulative instantaneous power can reach megawatts. This is exemplified by artificial lightning experimental devices. Inert gases (such as xenon) can be added to enhance UV radiation efficiency.

[0057] During the first, second, and third stage triggering processes of this system, A. Laser-to-exploding wire synchronization is required: the laser trigger signal and capacitor discharge must be synchronized within ±1ns (controlled by a delay generator); B. Exploding wire-to-arc synchronization is required: the peak moment of the exploding wire current (approximately 1μs) must match the peak voltage of the main discharge module. The circuit design utilizes magnetically insulated transmission lines (MITLs) to reduce current loss, and spark gap switches or solid-state SiC switches to ensure nanosecond-level conduction.

[0058] The plasma arc electro-optical conversion system is equipped with a special light-arc direction control device to direct the arc away from the vehicle body and shorten the arc discharge distance.

[0059] The arc direction can be controlled by active electromagnetic field guidance, passive / active hybrid gas dynamic control and optical guidance.

[0060] Among them, electromagnetic field guidance uses the Lorentz force to deflect the plasma (F=qv×B). Coaxial magnetic field coil technology can be used to arrange a pulsed magnetic field (0.1-1T) around the arc channel, and three-dimensional deflection can be achieved through current phase control, or a segmented anode-cathode structure can be used to guide the arc path through a dynamic potential difference (such as rotating arc technology).

[0061] The passive / active hybrid gas dynamics control method uses supersonic airflow to constrain the plasma jet, thereby deflecting the arc direction. Laval nozzles or vortex stabilization techniques can be used.

[0062] Optical guidance uses lasers to pre-ionize air to create a low-resistance path, guiding the arc along the optical path and deflecting the arc in the desired direction. UV laser beams or microwave-assisted techniques can be used.

[0063] Shorten the arc discharge distance. According to the energy-distance coupling model: the plasma jet distance d is mainly determined by:

[0064] Where P is power, τ is pulse width, ρ is air density, and Cp is specific heat capacity. Power modulation can be used to increase speed and reduce distance. Environmental medium control can be achieved by filling the arc with special gases, increasing the gas resistance, or doping with special material vapors to reduce the dielectric conductivity and shorten the arc distance. The arc direction and distance can also be altered by using the battery pack baffle as a parabolic reflector.

[0065] The spectral control system changes the energy of different output bands through spectral control (such as adding metal vapor), such as increasing the energy of non-visible light waves to reduce photochemical damage and visual effects on organisms.

[0066] The sensor system includes: ① power control sensor, ② pressure sensor, ③ temperature sensor, ④ position and displacement sensor, ⑤ humidity sensor, ⑥ spectrum and light intensity detector, ⑦ flame color detector, etc. These sensors should be widely configured according to the position of battery cells, battery module distribution, and each battery compartment to detect the changes in parameters at each location. All parameters will be transmitted to the (5) central control system for evaluating the start-up and start-up area of ​​the patented system.

[0067] Control sensors include voltage, current, resistance, and potential sensors. Pressure sensors include: A. Absolute pressure sensor (Absolute Pressure), B. Gauge pressure sensor (Gauge Pressure), C. Differential pressure sensor (Differential Pressure), D. Sealed pressure sensor (Sealed Pressure). Temperature sensors include: low temperature sensor, high temperature sensor, and temperature difference sensor, which are used to measure temperature parameters and temperature difference parameters between battery cells, between battery modules, and inside and outside the battery pack. Position and displacement sensors include: A. Linear position / displacement sensor, which is used to measure the movement distance or position change of battery cells, battery modules, and battery packs in a straight line direction; B. Angle / rotation position sensor, which is used to measure the angle or angular displacement of battery cells, battery modules, and battery packs around the axis. These parameters will provide accurate data to the (5) central control system when the car collides, rolls, falls, etc.

[0068] The humidity sensor will be used by the central control system to provide data support for evaluating the water ingress status of the vehicle after it falls into water or the battery pack integrity is damaged.

[0069] The spectrum and light intensity detectors, as well as the flame color detectors, can provide accurate data to the central control system. By analyzing the flame spectrum and intensity after a battery pack fire, the type of material on fire can be analyzed, thereby determining the location and severity of the fire, which is used to evaluate the start-up and activation area of ​​this patented system.

[0070] Light-blocking systems are categorized into two types: 1. Physical shielding devices, which directly block light through opaque or translucent materials and can be connected to the outer protective layer of the battery module or battery pack. 2. Optical filtering devices, which primarily utilize materials to selectively absorb or reflect light in specific wavelengths, such as neutral density filters (ND filters) and polarizing filters (CPLs).

[0071] The central control system is the core control system of this patented device. After receiving data from various parts and types of sensors configured in this patented system, it conducts a comprehensive analysis and issues instructions. The purpose is to ensure that the system starts with minimal delay while avoiding false triggering. At the same time, it also issues instructions: whether to release all the power of the battery pack or only release the power of some compartments. In addition, while issuing instructions to the subsystems it controls, this system will also issue an alarm to the occupants of the vehicle whether to evacuate quickly and the evacuation time limit. At the same time, it will issue an alarm outside the vehicle to warn other people to stay away from the accident vehicle. It can also warn other people and firefighters of the prohibited area of ​​the vehicle based on the arc direction and arc distance of the plasma arc of the high-efficiency electro-optical conversion system.

[0072] The serial numbers of the above embodiments of the present invention are for description only and do not represent the advantages or disadvantages of the embodiments.

[0073] In the above embodiments of the present invention, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0074] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. A device for suppressing battery pack fire, characterized in that: include: High-efficiency electro-optical conversion system, spectrum control system, sensor system, light isolation system and central control system; The high-efficiency electro-optical conversion system is configured to convert the electrical energy stored in the battery pack into light energy to reduce the heat release rate, total heat release amount and combustion growth rate index during fire. The high-efficiency electro-optical conversion system comprises: High-power pulsed laser electro-optical conversion subsystem, configured in each battery pack; The explosive wire electro-optical conversion subsystem is configured in each battery module; The plasma arc electro-optical conversion subsystem wraps around the entire battery pack; The triggering mode of the subsystem includes self-triggering or central control system command triggering; The high-power pulse laser electro-optical conversion subsystem is a first-level trigger device with a response time of 1-100ns; The exploding wire electro-optical conversion subsystem is a second-stage triggering device with a response time of 1-10 μs, which is triggered by the first stage via a photoconductive switch; The plasma arc electro-optical conversion subsystem is the third-stage main discharge device, which is triggered by the second stage through the wire explosion device.

2. The device according to claim 1, characterized in that: In the first-level → second-level → third-level triggering process of this system, the synchronization accuracy of the first and second levels is ±1ns, and the synchronization of the second and third levels must meet the requirement that the peak current moment of the exploding wire matches the peak voltage of the main discharge module.

3. The device according to any one of claims 1 or 2, characterized in that: The plasma arc electro-optical conversion subsystem includes an arc direction control device that directs the arc away from the vehicle body by at least one of the following methods: Electromagnetic field guidance, using the Lorentz force to deflect the plasma; Gas dynamics control, supersonic gas flow confinement of plasma jet; Optical guidance: laser pre-ionizes the air to form a low-resistance channel, guiding the arc to propagate along the optical path.

4. The device according to claim 3, characterized in that The arc direction control device shortens the discharge distance by power modulation or environmental medium regulation, satisfying the relationship: Where P is power, τ is pulse width, ρ is air density, and Cp is specific heat capacity.

5. The device according to claim 1, characterized in that The sensor system includes the following sensors distributed in the battery cells, modules and compartments: power control sensors, pressure sensors, temperature sensors, position and displacement sensors, humidity sensors, spectrum and light intensity detectors, and flame color detectors; these sensors should be configured according to the battery cell position, battery module distribution, and battery compartments to detect changes in parameters at each position.

6. The device according to claim 1, characterized in that The spectrum control system increases the energy proportion of the non-visible light band by adding metal vapor or filter structure to reduce damage to the organism.

7. The device according to claim 1, characterized in that The light isolation system includes a physical shielding device and an optical filtering device.

8. The device according to claim 7, characterized in that The physical shielding device includes an opaque or translucent material; the optical filtering device includes a neutral density filter or a polarizing filter.

9. The device according to claim 1, characterized in that The central control system is configured as follows: Assess the severity of the accident based on sensor data and choose to release all or part of the battery pack's power; Control self-trigger or command trigger mode to avoid false triggering; The system sends evacuation alarms and time limits to passengers inside the vehicle, and warns people outside the vehicle about arc hazard areas.

10. A method for suppressing battery pack fire using the device as claimed in claim 1, characterized in that: The following steps are involved: S1: Real-time monitoring of battery pack status parameters through the sensor system; S2: When the central control system determines that the battery pack has a fire risk, it triggers the high-efficiency electro-optical conversion system to convert electrical energy into light energy; S3: Adjust the output light spectrum through the spectrum control system to reduce damage to organisms; S4: Block or filter strong light radiation through light isolation system.

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