Gas Venting Technologies for EV Battery Safety

Battery module with a vent shield to mitigate damage to sensitive components when gases are vented from the battery cells. The shield is positioned directly along the vent path to absorb and redirect the hot, pressurized gases away from components like electronics and sensors. This prevents the gases from overheating and damaging those components.

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Vehicle with battery compartment safety system that automatically opens the compartment covers when battery temperature reaches a critical level to prevent thermal runaway propagation. The system uses thermosensitive devices to detect high battery temperature and pneumatic actuators to instantly open the compartment covers. This allows rapid cooling to contain thermal runaway without needing manual intervention.

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Battery design, manufacturing process, and heat sealing apparatus to improve gas venting reliability and prevent moisture ingress in sealed battery cells. The battery has a valve device inside the housing that releases pressure if it exceeds a threshold. The valve has a portion outside the sealing edge and another sandwiched between the sealing layers. Raised or recessed features are added to the sealing head surfaces to match the valve protrusions. This ensures proper valve operation during sealing and prevents deformation issues. The raised/recessed areas help maintain sealing while accommodating the valve movement during operation.

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Power supply device for vehicles like electric vehicles with improved cooling of the high-pressure gas released during cell venting. The device has a cover with internal gas guide passages that bend the gas flow path horizontally in sections. This reduces temperature rise of the vented gas by improving gas dispersion and mixing. The horizontal bends force the gas to change direction in the narrow confined space of the cover, promoting more efficient and uniform dispersion. This prevents hot spots and helps prevent excessive temperature rises in the vented gas.

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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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Electric vehicle design with improved safety in case of battery thermal events. The vehicle has longitudinal sills on each side and a battery pack sandwiched between them. If the battery overheats, it has a degassing device to release gases. A duct is formed between the battery and one sill to guide the gases out. This prevents them from reaching occupants or other components. A heat-resistant deflection device between the battery and sill can also be added to further protect against hot gases.

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Cooling battery cells to improve energy density and safety by coupling the ends of cells to opposite sides of a cooling plate. This allows closer cell packing without cooling tubes between cells. The cooling plate has ports for circulating coolant through to extract heat. The cells have vents at the non-coupled ends to release gas during thermal events. The cells have positive/negative faces and center/rim connections to simplify busbar connections. The cells can be electrically connected in parallel/series groups.

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High-voltage battery for electric vehicles that prevents damage to the electronic components during thermal events in the battery cells. The battery has a housing with separate compartments for the battery cells and components. A barrier seals between the compartments to prevent exhaust gas from damaged cells flowing into the component compartment. This isolates the components from the hot gas and ensures their functionality when a cell overheats.

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A secondary battery pack with improved thermal management to prevent propagation of thermal runaway between cells and minimize the effects of extreme temperatures. The pack uses a specific syntactic foam made of silicone rubber binder and hollow glass beads. This foam is sandwiched between the battery cells to insulate them from each other and the pack enclosure. It also absorbs thermal energy to reduce temperature spikes. The foam has low water absorption to prevent swelling in wet conditions. The pack may also have thermal management features like cooling channels, heat sinks, and spacers to further isolate cells and dissipate heat.

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Reducing thermal energy transfer between battery arrays of a battery pack to prevent venting during high temperature events. The technique involves using a phase change material (PCM) sandwiched between adjacent battery arrays and a thermal exchange device like a liquid coolant channel. The PCM absorbs excess heat from one array to prevent it transferring to the other array. This prevents one array overheating and venting due to thermal runaway, as the PCM acts as a thermal barrier. The PCM can be adhesively secured to the thermal exchange device.

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Battery pack for electric and hybrid vehicles that provides efficient temperature regulation without complex assembly or bulky housing. The pack has cells surrounded by a housing with integrated heat exchange zones between the cells and the coolant. This allows direct contact cooling without intermediate plates or hoses. The housing also has leak paths that channel coolant outwards if it leaks from the pack. This prevents coolant from pooling and allows rapid venting to prevent pressure buildup.

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Battery design with a valve that prevents internal gas pressure from building up while keeping out moisture. The valve is sandwiched between the housing halves and protrudes into the battery interior. This protects the valve during assembly and prevents damage from heat and pressure. The valve has a seal portion that extends further into the housing than the valve body. This avoids deformation, melting, and clogging during sealing. The valve has precise contacts and surface finishes to achieve controlled leakage between 5x10^-11 and 1.5x10^-10 Pa·m3/sec.

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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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Lithium-ion battery module design for electric vehicles that improves reliability, performance, and cost compared to existing lithium-ion battery modules. The module has a housing with partitions to create multiple compartments for individual lithium-ion cells. A cover seals the compartments and routes electrolyte into each cell. This allows better isolation and management of electrolyte in each cell to prevent issues like dry-out or overfilling. The module's design also enables efficient cooling and venting of the cells.

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A power supply device for electric vehicles, hybrid vehicles, and backup power applications that can inexpensively detect gas discharge from a battery cell. It uses thermal fuses in the gas exhaust path that melt when heated by the discharged gas. This indicates a cell venting problem. The fuses are placed in the gas guide path, avoiding direct exposure to the high-pressure, high-temperature gas. By having multiple fuses in the path, it can differentiate between a fused fuse vs disconnected voltage line. This allows detecting cell venting without unnecessary sensors in normal operation.

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Battery pack for electric vehicles with integrated venting in the cooling circuit to eliminate the need for separate venting valves. The pack has battery modules at different levels. A bypass tube connects the highest point of the cooling circuit to a lower point. Air accumulating at the top is sucked through the tube due to lower pressure there. This provides venting without valves. The tube outlet is in a lower cooling tube. The tube size relative to the tube cross section is limited to avoid impacting cooling performance.

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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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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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Tubular battery pack for electric vehicles and machinery with improved thermal management, safety, and recyclability compared to conventional battery packs. The tubular design uses thin tubes containing insulated lithium-ion cells for cooling and heating. The cells are mounted inside the tubes and electrically insulated from the walls using washers. Coolant circulates around the tubes to maintain optimal temperatures. This allows direct heat transfer from the cells to the coolant. The exposed cell surfaces radiate and convect heat to the inner tube wall. A shell encloses the tubes and coolant. Modules are formed with multiple tubes in a shell. The tubular pack has a battery management system and relief system for venting gases. The tubular design enables easy maintenance, recycling, and replacement of individual cells compared to glued packs.

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