Fire Suppression Methods for Electric Vehicle Batteries

Early detection and mitigation of thermal runaway in electric vehicle (EV) batteries to prevent fires and damage. The system uses sensors to detect outgassing, a precursor to thermal runaway, and alerts the fleet management system. This allows proactive response like evacuating the vehicle or redirecting assignments. On-board cooling and fire suppression can also be triggered. In EV facilities, the system identifies nearby vehicles and takes actions to protect them if a battery is outgassing.

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Safely packaging and cooling high-voltage battery packs in rail vehicles to prevent fires. The battery pack is enclosed in a separate fire protection cabinet filled with a liquid dielectric. The cabinet has a dielectric tank above it and a controllable valve to connect it. In normal operation, the tank provides cooling and maintains constant temperature. If a battery fault occurs, the valve opens to fill the cabinet with dielectric to extinguish fires. The compartment separates the battery from the driver's cabin for isolation. The tank is also connected to the battery cooling circuit as a compensating reservoir. A separate power converter cabinet has an aerosol cartridge for local fire suppression.

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Battery pack for electrified vehicles with vent gas passageways to mitigate thermal events and protect the enclosure while reducing debris discharge. The battery pack has a vent gas passageway within the enclosure that aligns with the cell vents. This passageway has inlet ports at each cell vent location. When a cell vent releases gas during a thermal event, it enters the corresponding inlet port and flows through the passageway instead of directly into the enclosure. This prevents gas discharge into the vehicle while mitigating pressure and temperature spikes. The passageway can also have features like serpentine channels or frangible sections to further reduce risks.

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Mitigating the hazards of battery thermal runaway in non-metal-air batteries by routing the hot gases generated during a thermal event through the metal-air batteries. This absorbs heat and prevents hot gases from escaping and igniting. Valves control air flow between the non-metal-air and metal-air batteries. They open when the non-metal-air battery temperature or pressure exceeds thresholds indicating runaway. This directs hot gases through the metal-air batteries instead of releasing them into the environment. The metal-air batteries' large thermal mass absorbs heat to lower the risk of ignition.

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Battery thermal suppression system for electric vehicle packs that mitigates thermal runaway propagation in battery cells during overcharge, overdischarge, overheating, short circuit events. The system uses aerosol devices integrated into the battery packs. The devices contain ignition and generating components that react to ignite when triggered. The aerosol particles disburse to cool the cells, preventing thermal cascading. The devices can be active or passive and implanted at battery array or pack level.

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Early detection and mitigation of thermal runaway in electric vehicle (EV) batteries to prevent fires. It uses sensors to monitor gas levels around the battery. If outgassing is detected, indicating thermal runaway, an alert is sent to the fleet management system. The system can then take actions like reassigning the EV, evacuating nearby vehicles, or deploying firewalls. On-board cooling is also triggered to suppress the runaway. This allows earlier intervention compared to just monitoring battery temperature.

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A battery pack design and control method to prevent thermal runaway propagation in electric vehicle battery packs. The battery pack has a case with a cavity containing the battery cells. A spray system is installed inside the case that can be activated in case of a thermal runaway event in one cell. The spray system sprays a fire suppressant into the cavity to extinguish the runaway cell and prevent further propagation. The suppressant is a material with a low melting point that turns into a liquid at the high temperatures encountered during runaway. This helps absorb and dissipate the heat from the runaway cell to contain it. The control method involves monitoring cell temperatures and activating the suppressant spray system if a cell reaches a certain threshold indicating runaway.

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Temperature control and fire suppression system for battery packs that uses the existing cooling loop to both regulate temperature and extinguish fires. The system has a pump, temperature control line with sections connected to battery subsystems, and a check valve before each subsystem. In normal operation, the pump circulates coolant through the line. If a fire occurs, the check valve blocks normal flow but allows coolant to escape at the subsystems to extinguish the fire. This leverages the existing cooling loop to both regulate temperature and suppress fires without additional components.

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Safety auxiliary system for modular lithium-ion batteries used in underwater vehicles to prevent catastrophic failures and contain thermal runaway. The system uses a refrigerant gas storage container connected to the battery modules. When sensors detect conditions indicating cell overheating, an electrovalve opens to inject the refrigerant gas into the module to quickly cool the cells. This prevents thermal runaway propagation. The system also monitors module sensors and if connection is lost or data indicates fire, it assumes a fire and forcibly injects and exhausts gas to extinguish.

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Battery assembly for electric aircraft that prevents thermal runaway propagation and mitigates fire risk. The battery has angled sides to contain the cells, insulation sleeves, and cooling plates between rows. The cooling plates facing the insulation are coated in flame retardant paint to prevent thermal runaway in one cell from spreading to adjacent cells. This helps contain any cell failures and prevent cascading failures.

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Thermal management and EMI mitigation materials for electronic devices like batteries that use coated fillers to improve performance and flexibility. The materials contain functional fillers like thermally-conductive particles, sand particles, or dielectric absorbers coated with a binder made of hydroxyl-terminated polymer crosslinked with a boron agent. The coating allows higher filler loadings of up to 98% for better properties like higher thermal conductivity while maintaining softness and conformability. The coated filler materials can be used as thermal interface materials between batteries and cooling plates to improve heat transfer. They also provide EMI mitigation and can act as fire suppressants if components catch fire.

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Battery pack thermal management system for electric vehicles that uses thermally activated valves to spray coolant into the pack when temperatures exceed a threshold. The valves have a body that allows coolant flow when open and a thermally activated material inside that blocks flow when closed. This prevents coolant leakage until needed. The valves are positioned on the pack perimeter and bias towards it to spray coolant inward. This allows contiguous coolant lines around the pack. The activated valves dispense coolant into modules during overheating events, mitigating thermal runaway.

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A step-by-step prevention and control system for electric vehicle battery packs that actively prevents and suppresses battery failures to improve safety. The system has three prevention stages: diagnosing battery faults, detecting cell thermal runaway, and preventing pack thermal runaway propagation. It uses a main controller to analyze monitoring data and send instructions to execute prevention actions at each stage. This allows targeted, escalating responses to battery issues instead of just reacting to full thermal runaway. The steps can include disconnecting faulty cells, isolating zones, extinguishing fires, and relieving pressure.

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Controlling thermal runaway propagation in battery packs with multiple modules by selectively discharging modules to prevent runaway spread. When a thermal runaway is detected in one module, the controller checks if current is flowing through that module. If not, it decouples the module to isolate the runaway. If current is flowing, it connects the other modules to an external load to discharge them, preventing runaway propagation. This controlled discharge can mitigate thermal runaway chain reactions in battery packs.

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Early detection of thermal incidents in electrochemical cells like batteries to prevent chain reactions and explosions. The system uses a thermally anisotropic material like graphite positioned near cell vents and thermal sensors. This material captures and absorbs heat from venting cells, preventing it from spreading. The sensors detect abnormal thermal energy in the anisotropic material indicating a thermal runaway. This allows early warning and action to isolate and disconnect affected cells.

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Mitigating thermal events in battery packs of electrified vehicles using nitrogen inflation. The battery pack has an enclosure with a bag that can generate and release nitrogen. When a thermal event is detected, the vehicle's controller commands the bag to inflate with nitrogen inside the enclosure. This suppresses further thermal runaway by displacing oxygen and reducing the flammable atmosphere. The controller also takes other corrective actions like gradual stopping, shutdown, alerts, and venting.

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Electric aircraft power system with integrated fire relief channels to prevent spread of cell fires. The system uses battery packs with tubes to contain cells. Cells are oriented with positive terminals facing exhaust channels. If a cell catches fire, fumes exit the tube and are diverted out of the aircraft. This prevents spread to adjacent cells. The packs are removable and lightweight instead of enclosed cases. The packs connect in series to power the aircraft. An exhaust channel directs any fires away from other packs. This allows higher cell density without encapsulation. Sensors monitor cell conditions.

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Mitigating the hazards of battery pack thermal runaway in electric vehicles by routing hot gases from a failing battery pack through adjacent metal-air battery packs. This absorbs heat and suppresses flames compared to releasing them into the vehicle or environment. Valves open when thermal sensors indicate cell failure to divert hot gases through metal-air cells. This prevents explosive ignition of ambient oxygen and reduces collateral damage.

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Thermal event management system for electric vehicles to prevent and mitigate thermal runaway events in battery packs. The system detects thermal events in battery packs using onboard sensors and responds by automatically powering down the vehicle, decoupling the affected pack, increasing cooling, and notifying the operator. This prevents propagation and reduces severity of thermal events.

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Containing thermal runaway and fires in lithium battery cells to prevent spread and damage. The method involves compartmentalizing battery cells into smaller isolated sections to contain a localized fire within that section. The compartments can be inside a larger container made of materials like cardboard, fiberglass, or aluminum that is coated with an intumescent fire retardant. This coating expands when heated to insulate and contain the fire. The compartments themselves can also be coated or made of fire-resistant materials.

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