Electric Vehicle Battery Safety Assurance Techniques

A method for safely charging a traction battery in electric vehicles to avoid overcharging and potential safety issues. The method involves monitoring battery parameters like the state of charge (SOC) during charging and discharging or stopping charging when the parameter changes by a certain threshold. This prevents continuous charging if the battery is already full, preventing overheating, lithium plating, and other problems.

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Smart connection sheet for battery packs that can provide automatic EV battery safety. The smart connection sheet has a conductive member to connect adjacent battery cells and a cut-off device that can be triggered to sever the conductive member. When a fault condition like a short circuit, overheat, or collision is detected, the cut-off device can be activated to disconnect the battery cells and prevent further damage.

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A hydrogen fuel cell forklift that uses a distributed architecture, where components like the hydrogen storage, fuel cell, cooling system, and energy storage are separate and located outside the fuel cell box. This allows easy access, maintenance, and safety improvements compared to integrated fuel cell systems. The hydrogen storage is outside the fuel cell to avoid leaks. The cooling system is separate for efficient cooling. The energy storage system recovers braking energy. A distributed air intake provides filtered air. The architecture provides modular components that can be accessed and serviced individually.

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Chassis design for electric vehicles to provide a secure connection between the vehicle chassis and the traction battery housing that will prevent detachment in the event of a rear impact. The chassis features projections that fit into corresponding recesses on the battery housing. This three-dimensional form fit engagement locks the battery housing securely onto the chassis beams in all directions.

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A battery design to enhance safety by using individual battery cell housings, boxes, and an isolation component. The battery packs multiple battery cells into individual boxes that have pressure relief regions. These boxes are then enclosed in a larger box. If a battery cell has a thermal runaway event, its housing can vent pressure into the first box without affecting nearby cells. The pressure relief regions prevent the boxes and larger enclosure from exploding. An isolation component between the boxes absorbs heat and gases from venting cells.

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A thermal management system for energy storage systems that uses oscillating heat pipes (OHPs) to keep individual cells at their desired temperature while insulating them if one cell goes into thermal runaway. The system includes a cold plate cell holder to cool the cells via heat absorption from one surface, and OHP covers around the other surface of the cells to cool them via additional heat absorption.

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Battery pack with a safety device to prevent fire or explosion propagation to adjacent modules when one module malfunctions. The device connects a resistor to the malfunctioning module to absorb its energy and prevent thermal runaway. An event detector identifies the bad module and a controller activates a switch to connect the resistor when needed. This isolates the faulty module from the others and prevents fires or explosions from spreading.

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A lithium metal battery with improved cycle stability and safety by using a negative electrode plate with a polymer protective film on the lithium-metal surface. The protective film contains a citric acid copolymer with carboxyl and hydroxyl groups that can react with lithium metal. This forms a strong, flexible film that reduces dendrite growth, electrolyte consumption, and improves coulomb efficiency. The film coating on the lithium metal surface improves cycle stability and safety.

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Vehicle battery with integrated safety feature to prevent fires. The battery has a cell assembly with cells that have degassing elements to release hot gas if cells fault. Inside the battery housing is a deactivating device filled with a combustion promoter. On contact with hot gas, the device releases the promoter to burn off the gas inside the housing, preventing ignition outside the battery.

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A motor vehicle with an electric drive that prevents thermal runaway of the battery system by conducting hot gas produced during a cell thermal event away from the battery. The vehicle has an underride protection plate under the battery that abuts the battery walls in certain regions to increase mechanical stability. This creates a gas channel between the plate and battery to direct hot gas out of the vehicle rather than allowing it to contact the battery. The underride plate abutting the battery walls provides load resistance, while the open channel routes the gas.

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Battery protection apparatus for electric vehicles that effectively protect the battery pack during collisions without adding excessive weight compared to previous battery pack protection systems. The battery protection apparatus includes a separate main body fixed under the vehicle that extends up to shield the battery pack side. This main body has a cavity and gaps to absorb and disperse collision forces from impacts rather than transmitting them directly to the battery pack. A protrusion on the vehicle sill between the main body and battery helps absorb forces.

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Smart fuse protection for the electrical systems of highly variable load applications like vehicles. The fuse protection uses parallel legs with different fuses and switches that can be separately controlled. A thermal fuse and solid state switch are in parallel. The switch can be activated based on current conditions to bypass the thermal fuse. A controller monitors the current and activates the switch when appropriate. This prevents nuisance failures from transient loads while still providing overcurrent protection.

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A power supply device for an electric vehicle with enhanced thermal insulation between stacked battery cells to prevent thermal runaway propagation. The device uses a thermal insulation sheet between cells that is made from inorganic fibers. This sheet provides effective thermal insulation while also having low rigidity to prevent displacement of adjacent cells. The inorganic fiber sheet reduces the risk of thermal runaway propagation through the battery stack.

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A thermal runaway barrier for use in preventing thermal runaway in battery modules. The barrier is a nonwoven fibrous insulation layer that contains inorganic fibers, fumed silica particles dispersed in the fiber matrix, and a binder to hold it together. This insulation layer is sandwiched between optional organic and inorganic encapsulation layers.

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A thermal suppression system for electrified vehicle battery packs that can mitigate and manage battery thermal events like fires or overheating. The system uses aerosol devices integrated into the battery array and/or pack. When triggered by high temperatures, the aerosol devices release aerosol particles that disperse over the battery cells to suppress thermal propagation. This helps contain and extinguish battery thermal events. The aerosol devices can be implanted within the battery array or pack, and are activated by temperature sensors and control modules.

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Battery box design to improve safety of batteries in electric vehicles and other applications. The box has a chamber filled with a fire suppressant agent like CO2 that can be released into the battery compartment if a cell overheats or vents gases. This prevents thermal runaway fires by flooding the battery area with a fire-extinguishing medium. The box also has relief mechanisms to vent pressure and avoid explosions.

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Lithium-ion batteries that are safe and fire-resistant for use in applications like electric vehicles. The key is using a fire-resistant electrolyte to prevent thermal runaway if the battery short circuits. The electrolyte contains a lactone compound, g-butyrolactone, that provides stability at high temperatures without igniting. The battery also uses electrodes with graphene for high performance and low internal resistance.

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A battery containment system for electronic devices, such as tablet computers used for in-flight entertainment systems, that reduces the risk of fire in the event of a lithium-ion battery thermal runaway. The battery enclosure has a cooling channel that ducts any gas exhausted during thermal runaway to a vent where it can mix with air outside. The long pathway and cooling from the channel lowers the temperature of the gases, including lithium gas, to avoid ignition when exposed to oxygen.

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Increasing lithium ion battery safety by preventing adhesive from blocking pressure relief mechanisms. A battery cell with a pressure relief mechanism is designed to have an isolation component that prevents adhesive from being applied between the cell and the component it attaches to. This allows the relief mechanism to function properly and vent gases if needed. The isolation component can have features like protrusions that surround the relief mechanism area to block adhesive access.

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Battery module design that protects against potentially dangerous high current conditions like short circuits. The battery module contains multiple battery cells, each of which has a cell blocking portion that can interrupt the current path if a high current flows. This protects against issues like a short circuit in one cell causing excessive current flow. The cells are also connected in series through a module fuse. The current level at which the cell blocking portion interrupts is set higher than the fuse blowout current, so the fuse will blow first in the event of a high current fault.

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