EV Battery Packaging to Prevent Thermal Runaway

Despite the commercial success of lithium-ion batteries (LIBs), risk thermal runaway, which can lead to dangerous fires, has become more concerning as LIB usage increases. Research focused on understanding causes runaway and how prevent or detect it. Additionally, novel runaway-resistant materials are being researched, different methods constructing LIBs that better isolate it from propagating. However, field firefighters using hundreds thousands liters water control large emergencies, highlighting need merge research with practical observations. To study battery fire, this utilized a temperature abuse method increase investigated whether be suppressed by applying external cooling during heating. The used were pouch-type ones subjected high states charge (SOC), primed increase. A spray was then devised tested reduce temperature. Results showed that, without cooling, fire occurred every time abuse. successfully prevented runaway. This observation shows reducer is effective than suppressant, substantially improve performance public safety.

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Battery module design to prevent thermal runaway propagation between cells in a battery pack. The module has a housing, a stack of battery cells, and two heat blocking members. The cell stack and first blocking member are vertically stacked. The second blocking member is between the stack and housing. This prevents lateral heat transfer between cells. The blocking members contact to fully isolate. The design forces contact between the vertical and lateral blocking to prevent gaps. This prevents flames and gases from spreading between cells and the housing.

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With the rapid development of battery energy storage technology, issue thermal runaway (TR) in lithium-ion batteries has become a key challenge restricting their safe application. This study presents an innovative protection strategy that integrates liquid cooling with sodium acetate trihydrate (SAT)-based composite phase change materials (CPCM) to mitigate TR and its propagation prismatic modules. Through numerical simulation, this systematically investigates mechanism optimization pathways for The results indicate pure SAT exhibits poor latent heat performance due low conductivity. In contrast, incorporation expanded graphite (EG) significantly enhances conductivity improves overall performance. Compared traditional paraffin-expanded (PA-EG), SAT-EG, 4.8 times higher than PA-EG, demonstrates more six effectiveness delaying (TRP). When combined cooling, effect is further enhanced, will not be triggered when initial abnormal generation rate relatively low. Even if experiences TR, prevented thickness SAT-EG exceeds 12 mm. Ambient temperature influences both peak timing occurrence modu... Read More

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ABSTRACT Heat generation during fast charging and discharging of lithiumion batteries (LIBs) remains a significant challenge, potentially leading to overheating, reduced performance, or thermal runaway. Traditional battery management systems (BTMS), such as airbased cooling indirect liquid using cold plates, often result in high gradientsboth vertically within cells horizontally across packsespecially under highcurrent discharge rates. To address these issues, this study introduces evaluates steadystate convectionbased esteroil immersion (EOIC) technique for LIBs. Numerical simulations based on the Newman, Tiedemann, Gu Kim model, aligned with multiscale multidimensional principles, were performed both single 18650 cylindrical cell 4S2P pack. Experimental validations conducted 2C 3C rates at 25C ambient temperature. The EOIC system demonstrated temperature reduction up 13C 15C pack compared natural air convection achieved 10C gradient simulation results closely matched experimental data, maximum deviation only 2C, confirming model's reliabi... Read More

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ABSTRACT The efficiency and effectiveness of a battery thermal management system (BTMS) primarily depend on the lesser heat capacity phase change material (PCM). To improve performance BTMS, bare batteries with different extended surfaces (straight arc) are considered to enhance dissipation heat, leading significant enhancement performance. In present study, numerical simulations carried out study impact influence CuO (10%) nano additive dispersion in PCM. Also, analyses by modifying geometries arc fins battery. Results reported that proposed improved life 61%90% compared conventional BTMS systems. Extended boost exchange surface area, batterytoPCM/CuO dissipation, form novel method for conduction during liquid fraction melting. This network expands increasing fin radial distance, enhancing At ambient temperature range 15C45C, PCM/CuO/fin substantially PCMbased 163%, 192%, 212%, respectively. These findings demonstrate possibility straight shapes PCM control. experimental results show how these designs optimize transport, improving control under varied operating si... Read More

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In some new energy aircraft powered by lithium-ion batteries (LIBs), the LIBs operate in semi-confined spaces. Therefore, studying thermal runaway (TR) characteristics of such spaces is significant to safety research aircraft. This paper investigated TR space using external heating, and compared it with open terms behavior temperature changes lithium ternary power The results show that process can be subdivided into seven different stages according LIBs. Compared LIB space, has an additional explosion stage. temperature, maximum 708 C, heating rate 72.3 C/s, while 552 32.1 C/s. study beneficial for subsequent provision certain theoretical guidance use environments.

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Heat transfer suppression sheet for battery packs that prevents thermal runaway propagation between battery cells. The sheet has a unique core-sheath binder fiber structure and processing method to achieve both strength and heat insulation. The binder fiber has a higher melting core enclosed by a lower melting sheath. Processing involves melting the sheath while the core remains solid. This retains the core framework to prevent inorganic particle falling, while fusing the sheath to hold particles. It allows high temperature processing without particle loss. The sheet has excellent strength and heat insulation compared to wet-formed sheets.

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Battery module housing with directed and controlled venting for lithium-ion battery packs in electric vehicles. The housing has two types of vents: burst vents to rapidly release excess gas buildup during cell operation, and selective permeability vents to slowly allow gas exchange between the cell stack and housing cavity. This enables directed venting of excess gases away from the vehicle cabin while still allowing controlled breathing of the cells. The burst vents open at high pressure thresholds, while the selective permeability vents have membranes that allow gas exchange but not moisture.

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Heat shield for protecting vehicle battery packs from thermal runaway and particle impact during battery failure. The shield has multiple layers with specific properties to absorb particle impact, distribute heat, and insulate against high temperatures. The innermost layer closest to the batteries is made of an elastic material to absorb impact force from particle ejection. This layer prevents damage to subsequent layers. The next layer is thermally resistant to insulate against high temperatures. Fillers in the impact layer distribute heat to prevent localized hot spots. The shield layers are chosen to balance thermal insulation, particle impact absorption, and elasticity.

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Battery module design to prevent thermal runaway propagation in stacked battery cells. The module has thermal runaway preventers between the cells that disperse heat from an overheating cell and prevent direct transfer to neighboring cells. This prevents thermal runaway chain reactions that can occur when one cell overheats. The preventers are installed in the module case between the cells in the stack.

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Battery module and rack design to suppress fires in battery packs and prevent propagation when thermal runaway occurs. The module has a valve nozzle to feed firewater into the module if vent gas or flames are detected. An expandable member inside the module absorbs fluid to block air inlets and outlets when the valve opens. This keeps the water level high to cool cells. The rack has a water tank, pipes, and sensors to feed water into modules if runaway is detected.

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Battery pack design to prevent thermal propagation between modules in the event of a thermal runaway. The pack has a busbar connecting the battery modules. The busbar has weaker sections facing the vent holes of the modules. These sections can disconnect or deform when gas is discharged during a thermal runaway, breaking the electrical connection between modules and preventing heat transfer. This contains the failure to just the affected module.

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Battery module and pack design to improve safety by containing thermal runaway events and preventing propagation between modules. The module has a venting hole and attached venting unit with a switchable flow path. The venting gas discharged from the cell assembly is routed through the unit to an outside. The unit has features like protrusions, spirals, and blocked paths to guide, rotate, and separate the venting gas. This prolongs exposure time and lowers temperature, preventing flames and sparks. It also prevents oxygen ingress and particles from flowing back into the module. The pack has a similar venting channel.

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Battery system design to prevent thermal runaway propagation in hybrid/electric vehicle batteries. The system uses insulating plates between subsets of cells inside the battery pack. The plates have wider outer ends that overhang the cell rows to separate them further. This isolates a thermal runaway in one subset from spreading to adjacent subsets. The plates also have a narrower central region between the subsets to allow for cell expansion. The wider outer ends and narrower central region prevent thermal propagation between subsets.

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Thermal runaway represents a critical factor of catastrophic failure in power battery systems, posing significant safety risks electric vehicle applications. Aluminum alloy casings serve as primary protective barrier, and comprehensive investigation their combustion characteristics is crucial for mitigating potential hazards lithium-ion systems. The present study systematically examines the influence dimensional variations flame-retardant Ni-based surface modifications on mechanisms 5052 aluminum employed configurations. Experimental findings reveal that ignition temperature decreased with oxygen pressure increased. application coating markedly increasing threshold to 1007.8 18.8 K. A robust predictive model characterizing its flame-resistant was developed, demonstrating exceptional statistical validity R2 values consistently exceeding 0.95. Microscopic morphological analysis zones revealed incorporation facilitates formation more oxide film denser solidification zone microstructure.

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A separator for lithium-ion batteries with improved heat resistance, thermal stability, and cycle life compared to conventional separators. The separator comprises a nanocellulose coating on a porous substrate with a surface tension ratio of 0.68 or higher. The nanocellulose can have modified groups like amines, carboxylic acids, sulfonic acids, borates, or phosphates. This enhances heat resistance and bonding strength. An adhesive layer can also be added to prevent coating delamination. The separator enables high energy density, safety, and cycle life in lithium-ion batteries.

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An all-solid-state battery with improved charge/discharge efficiency and lifespan compared to conventional solid-state batteries. The battery uses a coating layer made of a porous network of intertwined fibrous carbon that is coated with an inorganic electrolyte. This coating layer is sandwiched between the anode current collector and the solid electrolyte. The coating provides balanced ionic and electronic conductivity, eliminating the need for a separate anode active material. The coated porous carbon network allows lithium intercalation/deintercalation without internal short circuits, improving cycling stability.

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Energy storage cell design to prevent thermal runaway propagation between cells in high-density batteries like lithium-ion. The cell has an electrode/separator assembly inside a housing with a covering made of porous material between the assembly and housing. The porous covering allows heat transfer between the hotter assembly and cooler housing walls. It prevents insulating layers from trapping heat and stops excessive temperatures in one cell from spreading to others.

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Battery with enhanced high-temperature performance and thermal stability through the synergistic effect of additives in the electrolyte solution. The battery features a positive electrode plate with a single-side active material layer, a negative electrode plate with controlled surface area, and a separator. The electrolyte solution contains a lithium salt, organic solvent, a cyclic silane compound containing unsaturated bonds, and a fluorinated cyclic carbonate compound. The cyclic silane compound enhances the protective film formed on the negative electrode surface, while the fluorinated cyclic carbonate compound prevents electrolyte decomposition. This combination enables the battery to maintain high-temperature performance and thermal stability while achieving enhanced cycling performance compared to conventional lithium-ion batteries.

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A compound with a perfluoroalkyl group, a coating composition containing the compound, a method to make the compound, and an electronic device using the coating composition. The compound has a unique structure with a perfluoroalkyl group, a silane group, and a vinyl group. It can be easily synthesized by reacting a perfluoroalkyl compound with an alkoxy silane compound, followed by elimination to introduce a double bond. This provides a simple and compatible way to introduce a perfluoroalkyl group into compounds for coating applications. The compound and coating composition can have low dielectric properties and enhanced adhesion compared to directly introducing a perfluoroalkyl group into a coating.

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