Improved EV Battery Packaging Density for Reduced Thermal Propagation

High performance heat control members for separating battery cells or insulating battery components that have favorable resistance to heat propagation and fire propagation while minimizing thickness and weight of materials used. The members include reinforced aerogel composites with durability, compressibility, and thermal insulation properties for battery applications. The aerogel composites have a reinforcing phase like fibers or open-cell macroporous materials to enhance mechanical properties compared to pure aerogels. The reinforced aerogel composites have compressibility less than 25% at 25 kPa, density less than 0.3 g/cm3, and thermal conductivity less than 25 mW/mK.

Source

A thermal barrier assembly for traction battery packs that mitigates thermal runaway propagation between battery cells. The assembly has a heat spreader fin inside the cell stack that directs thermal energy from a cell into the pack enclosure instead of through the barrier. The fin extends between the cell and enclosure or between the insulation layers. This prevents thermal energy from spreading through the barrier to adjacent cells during a cell failure.

Source

Wrapped thermal barrier assembly for traction battery packs that both mitigates heat transfer and provides a sealed interface between the battery and the pack enclosure. The barrier has a structural component surrounded by a wrapping material. The wrapping is wrapped around edges of the barrier to seal against the pack enclosure and internal components like cross-members. This prevents thermal conduction and convection between the battery and pack while creating a sealed barrier to prevent coolant leakage.

Source

Battery design incorporating a thermal management component that regulates cell temperature through a novel spatial arrangement of components. The battery comprises a stack of cells arranged in a perpendicular stack orientation, with a thermal management component positioned between adjacent cells. This configuration enables the thermal management component to maintain optimal temperature across the cell stack while the cells themselves maintain their original orientation, thereby preventing thermal diffusion and runaway.

Source

A flexible multilayer thermal insulator for electric vehicle battery packs that inhibits flame propagation. The insulator comprises a multilayer wall with an outer layer, intermediate layer, and inner layer, each formed from interlaced mineral yarns. The layers are bonded with flame-resistant coatings and a pressure-sensitive adhesive, and are fixed together with filaments. The insulator provides a high level of thermal protection against flame propagation, meeting or exceeding industry standards for thermal runaway protection.

Source

Thermal management of battery packs in electrified vehicles to reduce heat propagation between battery compartments and facilitate venting. The technique involves using a thicker thermal barrier between adjacent battery cells than the cell height. This prevents direct cell-to-cell thermal conduction. A slot in the cover above the cells allows the barrier to project through. This allows venting while sealing the cells. The barrier can have features like a deflectable flap to contact the cover.

Source

A multi-layer insulation element for thermal and electrical insulation of rechargeable batteries, particularly lithium-ion batteries, comprising a first electrically insulating material, a second electrically insulating material, and an intermediate material, wherein the intermediate material is a textile and/or thermally insulating material. The insulation element is designed to provide thermal runaway protection, electrical insulation, and arc protection for battery cells and modules, while also enabling simple battery assembly.

Source

A battery pack for electric tools with improved thermal management to prevent overheating and fires. The pack features a heat management apparatus comprising thermal isolation plates between cells and the control board, and thermally conductive plates to dissipate heat to the outside. The isolation plates prevent heat transfer between adjacent cells and the control board, while the conductive plates enable controlled heat dissipation. The design enables effective thermal isolation and fire prevention while maintaining normal heat dissipation functionality.

Source

A protection element for preventing thermal runaway propagation in lithium-ion batteries, comprising a fiber layer with a flame-retardant finish, and a heat-reflecting coating that accumulates heat during thermal runaway and forms a localized hole to allow hot gases to escape while protecting adjacent cells. The protection element is designed to cover battery cells and their vents, preventing thermal runaway from spreading between cells.

Source

A battery module and pack with enhanced thermal management and safety features. The module includes a cell assembly, collection assembly, heat insulation member, and cushion assembly. The cushion assembly is positioned between adjacent cells and comprises a heat insulating member and two cushion members that absorb cell deformation and prevent electrolyte migration. The heat insulation member is located on the collection assembly side and includes grooves that match the cell explosion ports. The module design prevents thermal runaway propagation between cells and maintains module performance.

Source

A thermal barrier article for electric vehicle batteries that combines a thin, flexible multilayer material with blast and thermal resistance. The article comprises alternating layers of inorganic fabric and ceramic-based binder, with an adhesive layer on the fabric side. The material withstands both flexure conditioning and pyrotechnic blast tests, providing a safe thermal barrier for battery compartments in electric vehicles.

Source

A battery module with improved fire resistance and thermal diffusivity, comprising a plurality of battery cells and an insulating pad having a multi-layer structure disposed between the cells. The insulating pad includes a swelling pressure absorption layer, an insulating fire-resistant layer, and a thermal diffusion layer, which work together to prevent heat transfer and cell swelling while maintaining electrical insulation.

Source

A battery pack design that prevents thermal runaway between adjacent cells by asymmetrically arranging cooling plates and insulation sheets. The cooling plate is positioned closer to the cell's main surface, while the insulation sheet is positioned closer to the adjacent cell, thereby blocking heat transfer between cells and preventing chain reactions. This design enables effective cooling of individual cells while maintaining a balanced cooling load across the pack.

Source

Battery pack with improved thermal safety, comprising a plurality of single cells arranged in a staggered configuration to prevent direct thermal conduction between adjacent cells, thereby reducing the risk of thermal runaway propagation.

Source

A heat absorber for battery applications that achieves high thermal absorption efficiency while maintaining flame retardancy and mechanical integrity. The heat absorber comprises a bag filled with a hydrogel material, which is a three-dimensional network structure formed through a polymerization reaction. The hydrogel material exhibits excellent thermal absorption capacity, with a low onset temperature and high heat absorption coefficient. The heat absorber is designed to be molded at elevated temperatures, allowing it to provide effective thermal management without compromising its structural integrity. The heat absorber is particularly suitable for battery applications where thermal management is critical, particularly in high-speed charging scenarios where thermal runaway is a significant concern.

Source

A battery design that improves energy density by optimizing thermal management components. The battery features a unique arrangement of thermal management components, with thinner end components that match the reduced expansion forces of the battery cells at the edges. This design enables a more compact thermal management system that maintains performance while reducing overall battery size.

Source

A multilayer protective element for battery assemblies comprising at least two battery cells, the element comprising an elastic buffer layer made of a foamed or woven polymeric material and a heat-insulating barrier layer made of a ceramic material, arranged between the battery cells to compensate for dimensional changes and prevent heat propagation during thermal runaway.

Source

A battery with improved energy density and thermal management, comprising a plurality of thermal management components arranged along a first direction, with at least one battery cell group disposed between two adjacent components. Each battery cell group includes multiple battery cells arranged along a second direction perpendicular to the first direction, and a heat exchange cavity is provided within each thermal management component to regulate battery cell temperature.

Source

Thermal barrier system for managing heat transfer between battery cells in high-voltage traction battery packs. The system includes a thermal barrier structure positioned between adjacent battery cells, comprising an insulation layer sandwiched between foam layers, to prevent heat transfer and electrical shorts during thermal events. The insulation layer can be made of refractory ceramic fibers, mica, sheet moulding compound, or phenolic. The system can be applied to individual cell pairs or to entire cell banks, and can be integrated into the battery pack's end plates.

Source

Thermal management barrier for battery cells that enables effective cooling while preventing thermal runaway between cells. The barrier comprises a main body with a thermally insulating material and a thermally conductive layer coating on the first side. The barrier prevents heat transfer from the first side to the second side through the main body, while maintaining sufficient thermal conductivity for cooling. This design enables precise control over thermal distribution between battery cells while maintaining safety.

Source

Aerogel-based thermal insulation for electric vehicle battery enclosures that combines exceptional thermal performance with mechanical robustness. The insulation composition comprises aerogel particles and a fibrous component, including polymer and inorganic fibers, with a specific ratio of aerogel to fibers. The aerogel has a high thermal conductivity of up to 32 mW/mK at 25°C, while the fibrous component enhances mechanical strength and durability. The composition achieves optimal thermal insulation properties, mechanical stability, and fire resistance through careful mixing and processing parameters.

Source

Thermal barrier assembly for traction battery packs with sealed interfaces to prevent thermal energy transfer between adjacent cell stack compartments. The assembly connects to cell stack cross-members via a tongue-and-groove joint and interfaces with upper and lower enclosure structures, heat exchanger plates, and bus bars through sealed connections, including adhesive bonds and mechanical seals.

Source

Abstract In recent years, electric vehicles (EVs) have grown in popularity as a viable way to reduce greenhouse gas emissions by replacing conventional vehicles. The need for EV batteries is steadily increasing. An essential and expensive part of electric transportation is the battery. The operating temperature of the lithium-ion (Li-ion) battery significantly impacts the performance of the EV battery pack. Battery packs undergo temperature fluctuations during the charging and discharging procedures due to internal heat generation, necessitating an examination of the temperature distribution of the battery pack. The geometrical spacing between cells is considered larger and identical and is kept open on two sides for free air circulation. A novel battery thermal management system (BTMS) design is required to effectively dissipate heat from the prismatic battery pack module. The electro-thermal behaviour of the prismatic Li-ion battery pack module was investigated based on the high charge/discharge rate. This study presents the development of a three-dimensional free open-source OpenF... Read More

Source

Power supply device for electric vehicles with improved thermal management, comprising a plurality of battery cells, separators with integrated heat insulating members, and a restraining member. The separators feature an interposed plate, a sheet-like heat insulating member, a peripheral wall, and internal ribs that hold the heat insulating member in place. This configuration enables effective thermal isolation between adjacent battery cells while maintaining compact dimensions.

Source

Protective element for energy storage systems like lithium-ion batteries in electric vehicles that reduces the risk of thermal runaway and propagation. The protective element has two layers: an elastomeric layer and a flame retardant layer. The elastomeric layer is made of an elastomeric material like rubber and the flame retardant layer is designed to resist flames. The elastomeric layer provides mechanical protection for the battery cells, while the flame retardant layer prevents thermal runaway from spreading between cells. The layers are bonded together.

Source

A multi-layer protective element for batteries comprising a compressible, heat-insulating, and electrically insulating material, such as wool or cotton, arranged between battery cells to mitigate expansion, thermal runaway, and electrical shock risks while enabling environmentally friendly recycling.

Source

A lithium-ion secondary battery with improved thermal management, comprising a housing containing multiple battery cells and at least one internal cooling unit. The cooling unit is positioned between battery cells and features a coolant channel that extends along its length, dividing the housing into separate compartments. The cooling unit is in thermal contact with adjacent battery cells, enabling direct heat transfer and efficient thermal management.

Source

Battery packs are vital components for storing and releasing energy. However, during driving, the intensity of heat emission and mechanical performance of electric vehicles are interrelated but conflicting indicators. To address this problem, this study topologically optimizes the power pack support structure with multiple objectives of minimizing compliance and heat dissipation, aiming to achieve a comprehensive and integrated design scheme. A floating projection topology optimization (FPTO) method is proposed, which normalizes the objectives of structural compliance and heat dissipation and derives the sensitivity. FPTO demonstrates superior objective function values and smoother topology configuration compared to the solid isotropic material with penalization (SIMP) method. Finally, the proposed method is applied to the power pack support structure. The results demonstrate that the method obtains a design solution with excellent mechanical performance and high heat dissipation performance with a suitable trade-off. The lightweight design of the overall structure of the battery pac... Read More

Source

An intumescent sheet for thermal runaway management in electric vehicle batteries, comprising an alkali-silicate based binder, a porous thermal insulation additive, and char strength-imparting additives, that expands to form a mechanically robust inorganic char with good thermal insulation and dielectric strength at temperatures above 175°C. The sheet can be used as a spacer between cells or as a lining for battery modules and packs, and can be manufactured by impregnating a non-woven fiber mat with the binder solution and drying it.

Source

Aerogel blend composition for thermal insulation in rechargeable batteries, particularly for multi-cell configurations. The composition comprises aerogel particles that are specifically formulated to counterbalance the thermal insulation performance of other components in the battery. The aerogel particles are manufactured through conventional precipitation techniques, but are processed to achieve a uniform, aerated structure that enhances thermal conductivity while maintaining high insulation properties. This composition enables optimized thermal management in multi-cell rechargeable batteries by providing both thermal insulation and heat management capabilities.

Source

Cooling battery packs for electric aircraft using extendable fins on the separator plates between cells to improve cooling efficiency while minimizing size and weight. The fins extend into the cell gaps when needed to contact the cell surfaces and extract heat. They retract when not needed to avoid obstructing cell installation. Sensors monitor cell temperatures and control fin extension/retraction to optimize cooling. This allows effective cooling of the battery pack using minimal additional space compared to conventional cooling systems.

Source

A thin, flexible, non-dusting, and non-combustible thermal insulation composite with low thermal conductivity, comprising a silica aerogel core sandwiched between a polyamide-based adhesive layer and two thin, fire-resistant sheets. The composite achieves thicknesses below 5 mm without material failures or inhomogeneities, and exhibits improved compressibility and mechanical properties compared to conventional fiber-reinforced silica aerogel blankets.

Source

A battery with improved energy density and thermal management, comprising a plurality of battery cells arranged in a column and a thermal management component connected to the largest surface area of each cell. The thermal management component's size ratio to the cell surface area is optimized (0.1≤H1/H2≤2) to enable efficient heat transfer while minimizing space occupation, thereby enhancing battery performance.

Source

A composite material for heat, fire, and smoke protection in electrical devices, particularly batteries, comprising a first substrate with a high-melting inorganic material and a second substrate with a bullet-resistant material, where the two substrates are bonded together with a crosslinked polysiloxane polymer composition. The composite material exhibits high thermal stability, withstanding temperatures up to 1300°C for short periods and 1000°C for extended periods, while maintaining electrical integrity and resistance to abrasive hot gases.

Source

A laminated article for battery pack thermal management, comprising a central layer of ceramic or aerogel material defining voids containing endothermic agents, sandwiched between two silicone layers with flame retardant additives. The article provides enhanced thermal insulation and fire barrier properties for electric vehicle battery packs, preventing thermal runaway and propagation in the event of cell failure.

Source

Among different battery packaging technologies, cell-to-pack is a widely used method to reduce the cost and increase the volumetric density of battery packs. Unlike the traditional cell-to-module technology, it requires more robust management to keep the temperature uniformity of all cells within a desirable range to ensure good pack performances. Besides active cooling controls, the layout of cells within the battery pack plays an important role in cooling performances, and thus needs to be optimized for lower cooling costs considering the geometry limitations of the pack. This paper presents the layout optimization of the battery pack with active immersion cooling for the 21700 cylindrical battery pack under harsh loading conditions. Based on the experiment testing, the finite element model with electric and thermal couplings has been built in COMSOL Multiphysics. To reduce the high computational cost, a data-driven generative design method based on variational autoencoder has been developed, which could autonomously mine useful properties from the data set of existing battery layo... Read More

Source

Battery pack for electrified vehicles featuring a split thermal fin configuration that reduces thermal interface material (TIM) requirements. The battery pack includes a heat exchanger plate and a battery array positioned against it, with the array comprising a frame body and a split thermal fin received within the body. The split fin configuration enables direct contact between the fin sections and the frame body, eliminating the need for TIM between the fin and adjacent structures.

Source

A single-component, multilayer wall assembly for electric vehicle battery cells that provides a constant compression force, thermal conduction, thermal insulation, flame propagation protection, and electrical insulation. The assembly comprises a middle wall of flame-resistant yarn, intermediate layers bonded to the middle wall, and outer layers with self-adhesive surfaces that bond to the cell walls and intermediate layers. The assembly maintains a consistent stack-up pressure, dissipates heat, and prevents thermal runaway between adjacent cells.

Source

Energy storage system with enhanced thermal management for lithium-ion batteries. The system comprises a housing with multiple storage cells separated by a thermal management device comprising two layers: a pressure layer and an insulating layer. The pressure layer maintains internal pressure within the cells, while the insulating layer prevents thermal transfer between cells. The insulating layer is designed to be incompressible, ensuring that heat dissipation is maximized while maintaining cell integrity. This dual-layer design enables efficient thermal management of lithium-ion batteries, particularly in applications requiring rapid charging and high energy density.

Source

A protective sleeve for electric vehicle battery pack coolant tubes that provides thermal insulation, electromagnetic shielding, and thermal runaway protection in a single, easy-to-apply component. The sleeve features a multilayered construction including an inner textile layer, a foil layer, a fire-resistant coating, and multiple thermoplastic films, all bonded together with adhesives. The layers are arranged to provide a combination of thermal insulation, electromagnetic shielding, and thermal runaway protection to the coolant tubes.

Source

A battery cell pack for electric vehicles that integrates thermal protection and cooling into a single, compact design. The pack features a frame with a thermal protection plate that channels heat away from the cell vent, eliminating the need for a separate thermal protection plate between the cell and cabin floor. The frame also includes end walls that isolate terminals from coolant flow, preventing short circuits between adjacent packs. The pack's compact design eliminates the need for module structures, reducing weight and height while maintaining thermal performance.

Source

A method for manufacturing an electrically insulated conductor for battery systems, comprising providing an electrical conductor, covering its circumference with a fiber mat, and welding the mat's end portions to form a closed insulating sleeve. The fiber mat provides high-temperature insulation that can withstand thermal propagation events in battery systems.

Source

A flexible thermal insulator for electric vehicle battery packs that inhibits flame propagation between cells and from the pack itself. The insulator has a composite wall with layers like scrimmed PEEK, silica fabric, pressure sensitive adhesive, and release film. The composite wall provides thermal insulation and dielectric protection while also inhibiting flame propagation for 5-10 minutes at 1000°C. The flexible design allows easy installation around the pack and between cells.

Source

A multi-layered composite insulation material for lithium-ion battery packs in electric vehicles, comprising outer layers of high-temperature-resistant fibers such as para-aramid or meta-aramid, and an inner layer of ceramic or polyacrylonitrile fibers. The material is designed to slow thermal runaway events in damaged battery cells, providing a critical time buffer for emergency responders and protecting adjacent structures. The outer layers are bonded to the inner layer using techniques such as needle punching or thermal bonding, and may include additional features such as flame-retardant rayon fibers or woven high-temperature filaments.

Source

As the demand for electric vehicles (EVs) continues to rise, optimizing battery thermal management has become a critical aspect of enhancing overall vehicle performance, efficiency, and lifespan. This paper explores various strategies and technologies employed in the thermal management of EV batteries, with a focus on achieving optimal operating temperatures for improved energy density and charging efficiency. The study delves into active and passive cooling methods, thermal insulation techniques, and advanced materials utilized in the design of battery packs. Furthermore, it investigates the impact of temperature on battery degradation and explores innovative approaches to mitigate thermal stress, ultimately contributing to extended battery life. Through a combination of simulation studies and experimental analyses, this research aims to provide insights into the key parameters influencing battery thermal management in electric vehicles, facilitating the development of more robust and efficient cooling systems for the next generation of EVs.

Source

In the last decades of electric vehicle (EV) development, battery thermal management has become one of the remaining issues that must be appropriately handled to ensure robust EV design. Starting from researching safer and more durable battery cells that can resist thermal exposure, battery packing design has also become important to avoid thermal events causing an explosion or at least to prevent fatal loss if the explosion occurs. An optimal battery packing design can maintain the battery cell temperature at the most favorable range, i.e., 2540 C, with a temperature difference in each battery cell of 5 C at the maximum, which is considered the best working temperature. The design must also consider environmental temperature and humidity effects. Many design strategies have been reported, including novel battery pack constructions, a better selection of coolant materials, and a robust battery management system. However, those endeavors are faced with the main challenges in terms of design constraints that must be fulfilled, such as material and manufacturing costs, limited availa... Read More

Source

Battery pack with enhanced safety features, comprising a pack case, multiple battery modules with stacked cells, partition isolation members separating the modules, bus bar members connecting the modules, relay units connected to the bus bars, and an outer resistor unit connected to the relay units. The resistor unit is positioned at one inner side of the pack case to prevent thermal runaway propagation between modules in the event of an abnormal cell condition.

Source

This work investigates a packaging solution for high power density semiconductors (> 200 W/cm 2 ), allowing for a dramatic reduction in size and complexity of power electronics modules.The multiple layers in standard packaging structures degrade the cooling efficiency due as they lengthen the path between dies and heatsinks.Here, we reduce the layer count by merging the ceramic substrate and the heat exchanger in a single part.CFD simulations and experimental validation are performed on a single-chip cooling packaging, and demonstrate a 10-20 % reduction in thermal resistance over more traditional cooling solutions.

Source

This work investigates a packaging solution for high voltage semiconductors (20 kV), allowing for a dramatic reduction in size and complexity of power electronics modules. The standard packaging structures typically introduce a competition between electrical insulation (which requires thick insulating layers) and thermal performance (where thin, high thermal conductivity layers are preferred). Here, we introduce a concept which addresses this competition and is based on direct cooling using dielectric liquid. Single-chip heatsinks are designed, optimized using computational fluid dynamics (CFD), built and tested.

Source

A thermally insulating multilayer sheet for preventing thermal runaway in batteries, comprising a nonporous elastomeric barrier layer, a flexible foam layer disposed on the barrier layer, and a flame retardant component distributed within the foam layer or contacting its surface. The sheet provides thermal resistance through heat conduction barriers, heat absorption, and gas blocking, enabling effective thermal management in thin battery configurations.

Source