Heat Sinks for EV Battery Cooling

This study experimentally analyzes the performance of a passive thermal management system using three-dimensional (3D) pulsating heat pipe (PHP) designed for pouch cell batteries in electric vehicles. The term “3D” refers to complex spatial arrangement PHP, which features multiple interconnected loops arranged three dimensions maximize dissipation efficiency and improve temperature uniformity around battery pack. Lithium-ion cells are increasingly favored compact lightweight packs but managing their generation is crucial maintaining preventing failure. research investigates operational parameters 3D PHP by testing two working fluids (R134a Opteon-SF33), filling ratios (30%, 50%, 80%), various condenser conditions (natural forced convection at 5 °C, 20 35 °C). effectiveness was tested simulated discharge cycles, with power inputs ranging from 200 W. results show that significantly improves management. Additionally, Opteon-SF33, an environmentally friendly refrigerant, offers excellent transfer properties, making this fluid promising cooling solution vehicle batteries.

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ABSTRACT Cooling lithium‐ion batteries using phase change material and star‐shaped channel for flowing fluid is presented in this paper. The proposed design tested on six 21700 cylindrical battery cells. cells are placed a case filled with wax as material, where cooled four water channels cross‐section. flow assumed to be steady, fully developed, laminar. This study conducted COMSOL Multiphysics 5.6 software, assuming lumped analysis the incompressible both water. It was shown from results that temperature lowered by range of 9.43°C 11.07°C when discharged 15% 4C rate paraffin wax. While 9.13°C 10.51°C circular channels. When carried out without any cooling method during discharge, 6 reached 39.528°C, while 1 39.468°C. However, after case, dropped 29.788°C, 30.034°C, lowest 28.440°C 5. temperatures were recorded 30.146°C, 30.339°C, 28.996°C 6, 1, 5, respectively. replaced n ‐Octadecane wax, all approximately 27.4°C. showed achieved compared other designs methods. By comparing present published results, it found good agreement previous findings shows notable impro... Read More

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Abstract Batteries employed in electric vehicles are the important components due to their significant high heat capacity and energy density characteristics. However, these batteries experience drastic temperature rise generation, which is basically affected different discharge rates. To reduce this, phase change materials around as they possess latent capacity, compactness light weight nature without necessity of additional power. In present study transfer characteristics battery pack consisting 25 arranged a with paraffin PCM cells. first part work analysis carried out by varying rates evaluate thermal It observed that increase greater quantity accumulated near cells this limited conducting capabilities PCM. avoid fin configurations designed studied melting fraction average distribution within pack. Results reported M3 layout developed most effective reducing interior buildup while maintaining an optimal time. Additional examination at includes influence rest intervals, convection, configurations. The results indicate implementing intervals augmenting convection not only diminish p... Read More

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Cooling apparatus for lithium-ion batteries that allows expansion without degrading heat transfer. The cooling apparatus has a heatsink that contacts the battery on three sides to absorb heat. It also has a clearance portion that allows the battery to expand. Additionally, the heatsink has a metal plate with a spring arm to secure the battery. The clearance prevents pressure buildup and swelling, while the metal plate prevents contact loss during expansion. An elastomer between the heatsink and battery provides thermal conductivity and compression force to maintain contact. This enables efficient cooling and prevents overheating during fast charging and discharging.

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Battery pack design for mobile devices and electric vehicles that enhances heat management through a novel heat transfer system. The pack incorporates a heat sink with strategically positioned windows that match the cell vents, and a leg extending from the heat sink to the bus bar. The heat transfer material is integrated into the bus bar's design, covering both protrusions and concave sections. This multi-directional heat transfer system optimizes heat dissipation from both the bus bar and cell compartments, significantly reducing thermal stress and improving overall pack performance.

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Abstract Immersion cooling technology holds significant potential for Lithium-ion battery thermal management. This paper proposes a counterflow based management system (BTMS) under fast charging conditions, using high-thermal-conductivity silicone oil-based nanofluid as the coolant. Experimental equipment has been used to extract battery-related parameters, along with experimental test bed validation of immersion modeling. The performance CuO nanofluid, at 5% volume fraction, was found reduce maximum temperature by 1.09 °C and 32.59% in difference compared base fluid. impact various parameters on analyzed, revealing that increasing fraction can both difference. Furthermore, comparison between direct flow design revealed configuration, optimal separators location from top box, middle returning while upper lower parts directly entering flow, outperformed design, achieving 1.22 reduction highest average 2.79 temperature. Therefore, this innovative structure significantly enhance uniformity efficiency battery.

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Battery pack cooling design to improve thermal management and efficiency of battery cells. It uses a thermal component with channels to capture and move heat away from the cells. The component extends between rows of cells in the pack. Coolant flows through the channels to absorb cell heat and transfer it away. This reduces overall pack temperature, gradient across cells, and improves pack cooling.

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Battery module with improved flame propagation suppression and heat dissipation. The module has a container with a plate-shaped member inside that partitions the cell compartments. The plate has a thermally conductive elastic body and plates on either side. This allows the cells to deform against the elastic body during cycling. The elastic body contacts the cells to dissipate heat. The thermally conductive plates connect the elastic body to the container, allowing heat transfer. This prevents gaps and provides continuous heat pathway for suppression and dissipation.

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Battery system with enhanced thermal management and suppression of thermal runaway propagation between cells. The system uses two coolers, one with a fluid having higher thermal conductivity and one with a fluid having lower thermal conductivity. The lower conductivity fluid flow rate is increased when cell temperature exceeds a threshold to expand the outer case of the lower fluid cooler and physically isolate adjacent cells. This prevents thermal chain propagation by insulating the expanded case from nearby cells.

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Abstract This paper proposes a gravity heat pipe-air hybrid temperature control system to address the inadequate dissipation in power batteries under high-rate discharge conditions when using single cooling methods. The system’s performance was evaluated for series-arranged battery packs at rates above 5C. Results show that effectively meets thermal management requirements 3-cell 5C, but as number of cells increases seven, degrades, with uniformity exceeding 5 °C threshold, leading failure. To resolve this, “C-shaped” configuration adopted improved pack arrangement. Further analysis demonstrates optimized manages up 7C within air span 20 35 °C.

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Abstract Battery-powered electric vehicles have gained traction as a sustainable and efficient mode of transportation. These rely on large battery packs to provide the necessary energy for their operation. However, operation these generates heat, which necessitates effective management ensure safe reliable functioning vehicle. As demand higher density in lithium-ion power batteries increases, conventional cooling methods may no longer adequately meet heat dissipation requirements under high-rate discharge high ambient temperature conditions. Researchers are investigating alternative techniques, such phase change material cooling, optimize vehicle packs, including use paraffin beeswax. The experimental results indicate that beeswax-based is more thermal solution Li-ion compared paraffin-based PCM air cooling. system maintained consistently lower temperatures slower rises, leading better control over pack heating. This also demonstrated superior performance terms voltage stability capacity retention, exhibiting drops rate depletion. findings suggest offers significant advantages design... Read More

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<div class="section abstract"><div class="htmlview paragraph">Electric vehicles (EVs) are gaining popularity due to their zero tailpipe emissions, superior energy efficiency, and sustainable nature. EVs have various limitations, crucial one is the occurrence of thermal runaway in battery pack. During charging or discharging condition pack may result condition. This promotes requirement effective cooling arrangement around avoid localized peak temperature. In present work, management a 26650 Lithium iron phosphate (LFP) cell using natural convection air cooling, composite biobased phase change material (CBPCM) its combination with copper fins numerically investigated multi-scale multi dimension - Newman, Tiedenann, Gu Kim (MSMD-NTGK) model Ansys Fluent at an ambient temperature 306 K. Natural was found discharge rates 1C 3C, maintaining below safe limit 318 K for 80% DoD. However, temperatures increased 321.7 325.4 4C 5C respectively which indicating inadequacy high-powered electric vehicles. 4 mm thick layer CBPCM reduced average surface 312.7 314.8 rates, respectively, w... Read More

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A heat exchange system for battery packs that improves cooling during fast charging and prevents overheating. The system has three parts: a main heat exchanger with multiple sections, a peripheral heat exchanger around the battery modules, and inlet/outlet pipes. The main heat exchanger is divided into interconnected sections that alternate facing opposite directions. This allows more surface area for heat exchange. The peripheral heat exchanger surrounds the modules for additional cooling. The inlet/outlet pipes connect the main and peripheral heat exchangers. The arc-shaped pipe connecting sections allows better flow through the main heat exchanger. The system provides better overall heat dissipation compared to traditional designs.

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Battery module housing design with fins and channels to improve thermal management and dissipation of internal heat. The housing has a grid of fins extending from the walls. The fins absorb heat from the battery cells and dissipate it to air. The fins have channels between them to facilitate airflow. This allows natural convection cooling to distribute the heat more evenly. A heat sink can also be used to absorb heat from the fins and further enhance dissipation.

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Battery pack cooling system for electric vehicles that improves heat dissipation while avoiding short circuits and phase change material leaks. The system uses a centralized heat sink box with composite phase change material between the battery pack and the heat sink. Thermal conductive sheets between adjacent battery cells connect them to the heat sink. This allows heat transfer from the cells to the sink without risk of contact. The heat sink can also have a cooling channel. This centralized cooling reduces cell temperatures, prevents thermal runaway, and avoids issues of phase change materials melting or leaking.

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New energy storage battery pack design to improve temperature uniformity and cooling efficiency for better battery performance and lifespan. The battery pack has a base with a serpentine cooling plate on top that wraps around the battery cells. Each cell has a thermal conductive sheet on one side. Heat dissipation fins are on the other side. Side plates fit against the serpentine cooling plate. Guard plates connect the side plates. This configuration allows coolant to flow through the serpentine plate to cool the cells evenly. The fins directly contact the cells for faster heat transfer.

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Battery design with improved safety by dissipating internal heat more effectively. The battery has a housing, cell, pole element, and heat sink. The heat sink is attached to the housing to quickly discharge heat from the battery. By adding the external heat sink, it prevents excessive heat buildup inside the battery which can improve safety and reliability compared to just using an internal cooling plate.

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Battery pack design to improve battery cooling and reduce vehicle cooling system size. The battery pack uses a dual cooling system with a heat sink containing a phase change material (PCM) to absorb battery heat. This reduces the need for large radiators and pumps in the vehicle cooling system. The heat sink has a plate with grooves forming flow passages filled with cooling fluid. A PCM-filled receiving area connects the flow passages. This allows rapid cooling by fluid flow and slow cooling by PCM phase change. The heat sink plates sandwich between covers. The pack uses multiple identical heat sinks, each with its own fluid inlet and outlet pipes. This allows parallel cooling paths. The fluid flows between heat sinks through straight sections. This layout reduces overall cooling system size compared to a single large radiator.

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Battery pack with improved heat dissipation performance by using a heat dissipation member between adjacent battery cells that has a smaller height first area compared to a larger height second area. This creates a path for coolant to flow between the cells. The coolant is supplied to or drawn from the pack module, allowing it to flow through the heat dissipation member path and cool the cells. This provides secondary cooling to prevent damage to the cell cases by capturing the heat transferred from the cells and evaporating the coolant to generate steam. The steam then condenses and flows back through the member to the coolant source.

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Lithium-ion battery design for electric vehicles that eliminates the need for external cooling systems by maximizing heat transfer through the stacked battery cells themselves. The cells have discrete planar layers with larger surface area in the horizontal direction than vertical. This allows more heat transfer in the horizontal plane compared to vertical, promoting heat dissipation. The cells also use ceramic separators and solid electrolytes instead of flammable electrolytes. Additionally, external heat sinks can be added around the cells. The optimized cell design and internal heat transfer components allow adequate cooling without external coolant.

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