Thermal Runaway Prevention in EV Batteries

Battery pack that provides thermal management, detection of abnormal heating, detection of thermal runaway, thermal runaway propagation prevention, and fire spread prevention in batteries. The pack uses a coolant system that can discharge coolant directly onto overheating cells to rapidly cool them and prevent thermal runaway. The system uses deformation elements attached to each cell that bend if the cell overheats to unlock coolant tubes.

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Early detection of thermal runaway in battery packs to prevent propagation, using graphite sheets and sensors positioned near cell vents. The graphite has high in-plane thermal conductivity but low through-plane conductivity, so it absorbs and conducts away heat from a venting cell to stop runaway propagation. Sensors monitor the graphite temperature for signs of abnormal heat.

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Preventing thermal runaway in vehicle battery packs to mitigate fire hazards. The system uses additional battery packs that can cool the main battery packs when temperatures rise. Heat transfer modules connect the secondary packs to the main packs. When main pack temps exceed thresholds, the secondary packs activate to draw charge and use refrigerant to cool the main packs. This provides instant cooling when main packs overheat. The secondary packs reserve some charge for cooling the main packs vs. their own use.

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Cooling system for electric battery cells that adapts to the cells swelling as they age and degrade. The cooling system has a variable diameter cooling conduit that expands or contracts in response to cell swelling. This prevents coolant flow restrictions due to cell expansion. The diameter change is proportional to the cell's swelling mechanism. By matching the cooling conduit dimension to the cell's expansion, it ensures adequate coolant flow even as the battery cells enlarge over time. This helps maintain cooling performance and prevents thermal runaway during use.

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Battery pack thermal management system that provides consistent temperature across cells without complex plumbing and valves. The system uses semiconductor thermoelectric devices in direct contact with the cell surfaces to selectively cool or heat them. It involves a battery array, two heat exchange plates, and matching thermoelectric devices. The cells contact one plate for base cooling and the thermoelectrics contact the other plate for selective heating/cooling. A power bus and electronic switches allow powering the thermoelectrics through any branch. A controller monitors cell temps and adjusts thermoelectric power to balance them.

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Battery thermal management system with integrated fire suppression capability to prevent thermal runaway and fires in battery packs. The system uses a liquid cooling plate inside the battery pack to regulate temperatures. It also has a temperature sensing element that opens a valve when the battery core temperature reaches a threshold. This allows the coolant to flow into the battery cells and directly contact the core. If thermal runaway occurs, the coolant vaporizes at a high temperature, absorbing heat and quickly reducing the core temp. This isolates the core from air to extinguish fires. The system also has a control method to switch between normal thermal management, emergency firefighting, and joint operation modes.

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A battery design for mitigating thermal runaway in electric vehicle batteries, improving safety. The battery cells are grouped into subgroups and surrounded by dynamic enclosures that can close around a subgroup if it starts to overheat, contain any thermal runaway, and prevent spread to other subgroups. The enclosures have pivoting covers that can open and close, forming thermal and physical barriers as needed.

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Preventing battery thermal runaway by transferring energy from cells at risk to the battery pack to mitigate the runaway potential. It detects cells at risk of thermal runaway in a battery pack and then transfers the energy from those cells to the battery pack using existing systems like coolant loops, heating elements, and charging circuits. This dissipates the energy from the risky cells into the larger pack, preventing thermal runaway.

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Battery with passive thermal runaway prevention and recovery mechanism. The battery has resealable valves that let the battery release pressure to prevent an explosion. It also has a fluid reservoir above the battery cells that can gravity feed coolant into the cells to quench overheating. This system automatically douses and vents overheating cells to prevent thermal runaway. The valves can be resealed after an incident to reuse the cell.

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A composite material thermal shielding device to protect compartments from heat and flames during extreme events like battery fires. The device has metal layers separated by a polymer core. The polymer expands, increasing separation between the metal layers and thickness of the device when heated. This reduces heat flow through the device compared to solid metal shields. The polymer contains compounds that release gas when heated to activate expansion.

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Electric vehicle thermal management system that allows effective cooling and fire suppression of batteries without adding bulky fire extinguishing systems. The system uses a shared heat transfer fluid between the battery and motor. When the battery is normal or needs cooling, a valve closes to prevent fluid flow. If the battery overheats, a valve opens to let fluid flow from the motor to the battery. This shared fluid absorbs heat from the motor and transfers it to the overheated battery. If the battery is severely overheated, a release mechanism empties the fluid into the battery to cool and suppress fires. This shared fluid circulation avoids needing separate liquid cooling for each component, reducing space and cost.

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Intelligent thermal management system for power batteries in electric vehicles that accurately controls temperature of individual battery cells, recovers waste heat, and balances cell voltages without consuming pack energy. The system uses thermoelectric semiconductors on cell surfaces to precisely regulate cell temperatures. It also has a heat recovery module at one end of the pack to collect excess cell heat. This heat is converted and stored in an auxiliary battery. The thermal management controller coordinates all components via a CAN bus. This enables efficient and intelligent battery temperature control, heat recovery, and cell voltage balancing without draining pack energy.

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Power battery thermal runaway liquid cooling system for electric vehicles that can effectively control battery temperature during thermal runaway events. The system has two working states: one to control temperature rise inside the battery pack and reduce cell-to-cell temperature differences, and the other to manage thermal runaway events. The system uses an external pump, valves, and cooling piping connected to the battery pack. Inside the pack, a valve controls coolant flow. A controller uses battery temperature and CO sensors to switch between modes. In the first mode, the pump circulates coolant through the pack to regulate cell temps. In the second mode, the pump pumps coolant out of the pack and valves isolate cells to contain runaway. This prevents pack-wide thermal runaway.

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An automotive battery pack cooling system that prevents battery-related vehicle fires. The system uses a closed-loop liquid cooling circuit with aluminum pipes inside the battery pack. The circuit pumps a cooling fluid through the battery cells and an external heat exchanger. In case of cell rupture, the aluminum pipes deform and rupture, allowing fluid to leak out and prevent ignition. This prevents spontaneous combustion when a battery cell fails.

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Battery temperature control system for electric vehicles that uses thermoelectric modules to individually regulate temperature of specific battery locations, rather than relying on overall pack cooling. The system involves attaching thermoelectric modules directly to the battery surface. Each module has a thermoelectric element sandwiched between insulating plates. The modules can absorb or generate heat based on power input. Sensors on the battery measure local temperatures. A control unit adjusts module power to compensate for detected temperature differences. This allows targeted cooling/heating to prevent hotspots and uniformize pack temperature.

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Insulation system for vehicle components that selectively insulates the components during heat up and allows heat dissipation once the components reach operating temperature. The insulation system uses an enclosed chamber filled with carbon dioxide that has different thermal conductivity in liquid/gas vs supercritical gas phase. This allows the insulation to change its thermal properties as the component temperature increases.

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Power battery thermal runaway cooling and extinguishing system for electric vehicles that prevents battery fires and explosions by integrating cooling and extinguishing into the battery design. The system uses high-temperature fusible material cooling blocks attached to the battery cells. When the cell temperature exceeds the block melting point, it dissolves and floods the cell with coolant to quench overheating or fires. The blocks are connected in series with the battery terminals and circulate cooling fluid through the pack.

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Battery pack thermal management system for electric vehicles that uses thermoelectric devices to balance voltage between cells and control temperature. The system has thermoelectric devices in thermal contact with some cells to transfer current and heat between cells. It also has thermometers to measure cell temperatures. An electronic controller balances cell voltages by selectively transferring current through thermoelectric devices. This allows balancing without resistive loads that waste energy. The controller also manages temperature by controlling thermoelectric current based on cell error. This prevents excessive heating or cooling from cell imbalances. The thermoelectric devices extract waste heat from cells with imbalanced charge and inject it into cells with lower charge. This improves cell life by preventing overheating.

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Virtual cells for battery heat management to prevent overheating and thermal runaway by actively controlling heat generation from inside the battery. When a cell temperature exceeds a limit, virtual cells are activated to supply or sink current from adjacent cells to reduce their heat generation. This prevents individual cells from overheating and balances overall pack temperature without relying solely on external cooling.

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Thermal vent management system to isolate and control gas discharges from rechargeable energy storage systems like vehicle batteries. The system captures and directs the gases away from the battery housing to prevent the build-up of explosive concentrations. It uses a one-way valve vent that connects to a chamber with an air inlet. The inlet draws ambient air using a Venturi effect to dilute and safely exhaust any vented gases.

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