Phase Change Materials for Passive Cooling of EV Batteries

Protecting batteries in electric vehicles (EVs) and other applications to enhance safety and reliability using multifunctional battery modules with tubular energy absorbers filled with phase change materials (PCMs). The tubes surround the batteries and absorb impact forces during crashes. The PCMs squeeze out through orifices in the tubes, further increasing energy absorption. The tubes also dissipate heat from the batteries using the PCMs. The thin-walled tubes provide improved energy absorption compared to hollow tubes. The PCM-filled tubes have optimized geometric parameters for lateral compression.

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Passive cooling system for battery cells in electric vehicles that does not require active cooling pumps or electrically conductive coolant channels. The system uses a housing with battery cells surrounded by a porous media filled with a phase change material. The phase change material vaporizes when heated and condenses back to liquid when cooled. A cold plate at the top cools the vaporized material. This allows the cells to be cooled passively without active cooling. The porous media channels along the cells help distribute the cooling.

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Battery pack system for electric vehicles with improved thermal runaway mitigation. The system uses a thermochemical material that undergoes an endothermic reaction above 50°C to absorb excess heat and prevent thermal runaway propagation. The material can be located inside the stack of battery cells, between cell edges, or in adjacent gaps. It can also be in a reservoir with valves that release upon threshold conditions like temperature or pressure. The material absorbs heat from thermal events to quench them and prevent spread.

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Battery pack design with improved safety during thermal runaway events to prevent chain reactions and explosions. The pack has a case with features that isolate and vent overheating batteries. The battery modules are fixed to the case at a distance from the bottom plate. Between the plate and modules is a phase change material pad that vaporizes at high temperatures. If a module overheats, the pad expands and separates the module from the plate to prevent heat transfer. This isolates the overheating module and prevents propagation of thermal runaway to adjacent modules.

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Abstract This paper proposes a versatile thermal management solution utilizing phase change material (PCM) for compact 21700 battery modules. First, flame-retardant and heat-conductive pouring sealant is utilized to encapsulate the PCM. The impact of diameter number PCM columns on performance module evaluated by single-factor multi-objective optimization methods. Then, low-temperature heating scheme film heaters devised module. results indicate that heat generation diminishes as working temperature rises, whereas it escalates with an increase in discharge rate. When 8 inner outer heights are 66 mm 13 mm, maximum difference controlled at 45.6 C 4.61 C, respectively. With power 13.6 W, average may from -5 11.7 25 minutes, resulting differential 4.6 C.

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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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Under high-rate charging and discharging conditions, the coupling of phase change materials (PCMs) with liquid cooling proves to be an effective approach for controlling battery pack operating temperature performance. To address inherent low thermal conductivity PCM enhance heat transfer from plates, numerical simulations were conducted investigate effects installing fins between upper lower plates on distribution. The results demonstrated that merely adding surfaces filling in inter-cell gaps had limited effectiveness reducing maximum temperatures during 4C discharge (8A current), achieving only a 1.8 K reduction peak while increasing difference over 10 K. Cooling incorporating optimized flow channel configurations fins, alternating coolant inlet/outlet arrangements, appropriate increases rate (0.5 m/s), reduced inlet (293.15 K) could maintain below 306 constraining differences approximately 5 discharge. Although increased rates enhanced efficiency, improvements became negligible beyond 0.7 m/s due limitations conductivity. Excessively found adversely affect control initial phases. ... Read More

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Enhancing heat capacity of liquids for applications like cooling, heating, and thermal storage without using ice slurries. The method involves combining liquids with different phase transitions to create compositions where the temperature ranges of the phase transitions overlap or are adjacent. This allows the compositions to have enhanced heat capacity over a broader temperature range compared to single-phase liquids. The phase transitions can be liquid-liquid phase transitions or solid-liquid phase changes. Adjusting the concentrations of the components allows tuning the phase transition temperatures. The compositions can be used in applications like cooling, heating, and thermal storage where higher heat capacity liquids are needed.

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Battery thermal management systems (BTMS) ensure the safety and performance of lithium-ion batteries, which power electric vehicles. However, designing an effective BTMS is challenging due to batteries' complex behaviour sensitivity temperature variations. This review comprehensively explores current vital technologies trends in BTMS, explicitly focusing on analysing various cooling control strategies. To discuss four primary technologies: air cooling, liquid immersion phase change material (PCM) cooling. The advantages disadvantages each technology are compared terms cost-effectiveness, applicability, limitations when dealing with high-energy-density batteries. Furthermore, delves into discussion strategies data prediction methods for emphasizing importance advanced analysis optimising battery safety. Different strategies, such as passive, active, hybrid control, introduced evaluated. Data methods, artificial neural networks, fuzzy logic, machine learning, also presented discussed. comprehensive provides in-depth understanding while serving a valuable reference future research appli... Read More

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Simultaneously charging multiple thermal batteries in transportation vehicles like trucks, trailers, and carts without using large industrial chillers. The batteries have a closed-loop cooling system with a phase change material (PCM) and heat exchangers. The vehicles' cargo areas are also cooled using the PCM. To charge the batteries, an external charging source connects to ports on the vehicles. An onboard pump circulates a heat-transfer fluid between the cargo area, PCM, and external ports. An industrial chiller charges the central storage reservoir over a longer time. This allows simultaneous battery charging without needing large chillers on each vehicle.

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Abstract To address the limitations of conventional energy systems and optimize conversion pathways efficiency, a type five-in-one multifunctional phase-change composite with magnetothermal, electrothermal, solar-thermal, thermoelectric electromagnetic shielding functions is developed for multipurpose applications. Such novel fabricated by an innovative combination paraffin wax (PW) as material carbonized polyimide/Kevlar/graphene oxide@ZIF-67 complex aerogel supporting material. The exhibits unique bidirectional porous structure high porosity robust skeleton to support loading PW. reduced graphene oxide CoNC resulting from high-temperature carbonization are anchored on generate thermal conduction magnetic effect, enhancing phonon electron transfer improving its efficiency. not only excellent thermoelectric, magnetothermal performance, but also achieves interference effectiveness 66.2 dB in X -band. introduction PW significantly improves energy-storage capacity during multi-energy conversion. great application potential efficient solar utilization, sustainable power generation,... Read More

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A tool and method for connecting electronic components to cooling surfaces like heat sinks without the need for fragile thermal interface material (TIM) foils. The tool has a base with a cavity shaped to match the contour of the cooling surface. A flexible pad is attached inside the cavity. When the component is placed on the tool, the flexible pad conforms to the component's shape and provides a gap-free thermal contact between the component and the cooling surface. The tool can be used in any orientation, vertical or horizontal, without needing to align delicate TIM foils. The flexible pad replaces the need for fragile TIM foils, simplifying component installation and maintenance.

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Power supply device with improved heat dissipation and size reduction for applications like electric vehicles. The device uses a case filled with insulating heat dissipation resin to surround and contact heat generating components like semiconductors. This allows direct thermal conduction between the components and the resin, improving dissipation compared to insulated components. The components can also be arranged with different volumes and in contact with the case wall. This leverages the resin and case as additional heat sinks. The compact design enables efficient dissipation of heat from components while reducing overall device size compared to separate heat sinks.

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Manufacturing a composite material with improved thermal conductivity by planarizing the surface of the metal foam component before forming the composite. The process involves planarizing the metal foam (step b) before or during mixing with the curable polymer (step c) to create a smoother surface. This increases the bonding area between the composite and the material it contacts, improving heat transfer efficiency. Planarization can be done on the metal foam precursor, the metal foam, the polymer-foam mixture, or the cured composite.

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Battery module with enhanced thermal management through strategically integrated phase change materials (PCMs) that absorb heat generated in critical battery connections. The module features a bus bar with integrated phase change members that distribute heat from connecting areas between the cell tab and bus bar, while a secondary phase change member is positioned on the top surface of the cell. This dual-phase design enables targeted cooling of high-temperature areas, particularly the connecting region between the cell tab and bus bar, while maintaining overall system thermal balance. The phase change materials are designed to absorb and release heat efficiently, preventing thermal runaway and fire hazards.

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Inside a closed, thin-walled hollow cylinder, there is solid state of phase change material (NePCM) that has been nano-enhanced. This NePCM heated at its bottom, with nanoparticles (Al2O3) inserted and homogenized within the PCM (sodium acetate trihydrate, C2H3O2Na) to create NePCM. The cylinder thermally insulated from outside ambient temperature, while heat supplied sufficient cause change. Once entire converted liquid due heating, it then cooled, thermal insulation removed. cylindrical liquefied bar cooled in this manner. Thermal entropy, entransy dissipation rate, efficiency during heating cooling were analyzed by changing variables. volume fraction ratio nanoparticles, inlet flux, height variables considered. results indicate significant impact on liquefaction convective when values these are altered. For instance, an increase 3% 9%, constant flux 104 Wm2 0.02 m, decreases 99%. entropy conduction through significantly lower compared air surface. increases average 110% without any cooling. With 6%, 80% as m.

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Bonding metal filaments directly to the surface of an electronic substrate to form a heat sink without using a separate thermal interface material. The filaments are formed by processes like ball bonding, wedge bonding, ribbon bonding, and chain bonding. The filaments are heated and placed on the substrate surface to weld them in place. This creates a tailorable, high-density network of filaments that dissipate heat from the substrate. The filaments can be extended away from the substrate or joined back to form an individual heat sink. Repeating the process creates a plurality of filaments that cool the substrate. This eliminates the need for a separate thermal interface material to attach a separate heat sink.

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Agglomerated boron nitride powder for heat dissipation sheets with improved thermal conductivity and electrical insulation properties. The agglomerated BN powder has a specific tap density range of 0.6-0.8 g/mL and interparticle void volume of 0.5 mL/g. This density range allows the BN particles to pack closely without excess voids while still allowing interparticle movement for thermal conductivity. The optimized BN powder enables heat dissipation sheets with high thermal conductivity and good electrical insulation properties compared to standard BN powders.

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Batteries with improved performance, durability, and safety for electric vehicles and other applications. The batteries have features like phase change materials, thermally conductive articles, and housing designs that mitigate heat generation and cell expansion during charging/discharging. The phase change materials absorb excess heat from cells, cooling them. Thermally conductive articles align cells and facilitate heat transfer. Uniform pressure distribution is achieved by housing components. These features allow high energy density batteries with reduced deleterious effects of lithium metal cells.

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High thermal conductivity heat conductive silicone composition with improved slide resistance for use in heat dissipation applications like electronics. The composition contains a crosslinked silicone gel, a specific silicone oil, a heat conductive filler, and gallium or a gallium alloy. The gallium or gallium alloy with a melting point between -20°C and 100°C provides high thermal conductivity. The gallium also improves slide resistance compared to compositions without gallium.

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