Phase Change Materials for Passive Cooling of EV Batteries

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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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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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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Preparing ultra-thin copper foam with small thickness and high water absorption for use in heat dissipation applications in electronic devices. The preparation method involves electroforming copper foam in a specialized electrochemical cell setup. The cell has a cathode electrode with a porous substrate and an anode electrode with a soluble coating. The copper foam is grown on the cathode by electrolysis, with the soluble anode coating dissolving into the electrolyte as the foam grows. This allows the foam thickness to be precisely controlled by adjusting the anode coating dissolution rate. The resulting ultra-thin copper foam has a thickness as low as 50 microns while still retaining excellent water absorption properties.

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A lightweight, flexible heat control structure for spacecraft and electronics with high temperature gradients. It uses multiple graphite sheets held at ends by clamping members. The exposed edges of the graphite sheets contact the heat source and dissipation targets. This allows efficient heat transfer with a simple, flexible design that can handle large temperature differences. The graphite sheets can be made from polymer films like polyoxadiazole or polybenzothiazole. The clamping members hold the graphite sheets with parallel basal planes and spaced edge planes.

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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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Simplifying the assembly of battery submodules for electric vehicles to reduce complexity and costs. The submodule design involves stacking pouch cells and welding electrode tabs between cells without removing them from the stack. This eliminates the need for complex handling of flexible pouch cells. The submodule is then attached to a frame and heat sink, with busbars added prior to welding the electrode tabs to them. This allows joining the cells without damaging the frame. The submodule can be stacked with others to form a battery module.

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Sandwich structure with high heat dissipation and mechanical properties for applications like electronics cooling. The structure has a thermally conductive sheet sandwiched between fiber-reinforced sheets. The thermally conductive sheet has a high in-plane thermal conductivity of 300 W/mK or more. It is not bonded to the core fiber-reinforced sheets, allowing the core to bear most stress. This prevents destruction of the thermally conductive sheet. The fiber-reinforced sheets have higher modulus than the core to provide strength. The core can be a porous material for lightweight. The sandwich structure is made by sequentially pressing the components. This allows the thermally conductive sheet to be positioned accurately without displacement.

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Spiral-shaped heat sink design with internal flow channels that have communicating sections to circulate refrigerant. The spiral channels allow evenly distributed cooling performance through temperature control at the heat sink contact surface with the electronic device. The spiral shape creates turbulence and counter flow for enhanced heat transfer. The communicating sections allow circulating refrigerant flow between channels for improved cooling.

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Charging inlet assembly with integrated cooling to prevent overheating of the charging terminals during high current charging. The cooling module has phase change elements enclosed in pockets on a carrier that is thermally connected to the charging terminals. The phase change elements absorb heat from the terminals during charging to lower their operating temperatures.

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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 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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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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Composite material for high thermal conductivity that maintains stability after cyclic heating and cooling. The composite has a metallic phase (90% Ag or Cu) and a non-metallic phase with a coated core material (carbon like diamond). The core material has a carbide layer (Ti, Cr, Ta, V) covering part of the surface. The composite also contains trace amounts (0.0004-1.3%) of elements like yttrium, magnesium, silicon, boron, zirconium. These elements improve thermal conductivity and stability after cycling. The specific element reduces oxides on the metal core particles, allowing better reaction with carbon to form the carbide layer. This intimate contact between the metal and carbon phases prevents separation during thermal cycling.

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Battery module design for uniformly and efficiently heating and cooling the module to maintain optimal cell performance in extreme environments. The module has composite fins interposed between adjacent battery cells. The fins have compressive pads, cooling fins, and heating films. This allows direct heat transfer between cells without contact, improving heating uniformity compared to external heaters. The fins also enable efficient cooling by direct contact. The fins are positioned between cells instead of on the side walls to reduce heating time, temperature deviation, and degradation.

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