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The miniaturization of electronic devices has led to an increase in power density and functional integration, resulting in rapid heat accumulation that adversely affects operational stability and service life. Dielectric composite films with excellent thermal conductivity and insulating properties are highly desired for addressing thermal management issues in electronic packaging applications. Hexagonal boron nitride (h-BN) is a promising filler for such composites due to its outstanding thermal conductivity, insulating properties, and chemical stability. However, the inherent platelike structure of h-BN causes significant anisotropy and poor miscibility with polymers, limiting the uniform conduction of heat. This study proposes a high-temperature sintering method that transforms flaky h-BN plates into irregular multifaceted particles. This transformation reduces thermal anisotropy and creates uniform heat conduction pathways. The resulting sintered BN/Epoxy (s-BN/EP) composite films exhibit exceptional thermal conductivity, with in-plane thermal conductivity increased by 36 % to 6.0 W m−1 K−1 and through-plane thermal conductivity increased by 39 % to 1.2 W m−1 K−1 compared to pristine h-BN/epoxy composites. Moreover, s-BN/EP films could maintain low dielectric constant (D k , 3.22) and dielectric loss (D f , 0.015) at 5 GHz. This innovative approach provides a significant advancement in the development of high-performance insulating polymer composites, offering a promising solution for thermal management in high-power-density electronic packaging. [Display omitted] [ABSTRACT FROM AUTHOR]

In the rapidly advancing field of 5G technology, efficient thermal management is essential for enhancing the performance and reliability of high-power-density integrated circuits (ICs). This paper introduces an innovative approach to cooling these critical components, significantly surpassing traditional methods. Our design optimizes heatsink and fan configurations through systematic experimentation, varying fin shapes, heatsink dimensions, and fan speeds. The results demonstrate that fan velocity is the most critical factor in reducing IC temperatures, as increased airflow dramatically lowers thermal output. Expanding the heatsink surface area further improves heat dissipation by enhancing airflow interaction, while a larger copper heatsink boosts thermal conduction, effectively reducing the final IC temperature. These optimizations streamline the cooling process, minimizing the need for more complex and expensive equipment. This research sets a new benchmark in thermal management, fostering the development of more efficient and reliable electronic systems in the era of advanced wireless communications. Our approach brings a new dimension to existing research by focusing on the optimization of heatsink and airflow designs specifically for ICs. While previous studies have explored broader thermal management strategies, our work addresses specific challenges in heat dissipation by refining geometric configurations and fan speed adjustments. These optimizations result in measurable improvements in both efficiency and scalability, particularly within the context of high-power 5G systems. [ABSTRACT FROM AUTHOR]

In the present work, direct contact the refrigerant and the cells was employed for thermal management. This study experimentally investigates cooling the battery pack by allowing the refrigerant to directly contact the cells. Furthermore, it presents the first experimental evaluation of combining this approach with various active and passive cooling methods. According to the results, the cells' maximum temperature decreased by 34°C at the end of the discharge. In the proposed system, the heatsink served as the only heat transfer path to the environment, where. heat transfer occurred via free convection. To enhance heat dissipation from the heatsink, the system was combined with active or passive Battery Thermal Management Systems (BTMSs). Using hydrogel between the fins of the heatsink decreased the cells' maximum temperature by 0.5°C. However, the use of forced airflow between the fins of the heatsink did not affect the cells' maximum temperature. The proposed system was also combined with an active forced liquid cooling system, and various water flow rates were investigated. At a flow rate of 200 LPH, the cells' maximum temperature was reduced by 1.5°C compared to the mode without forced water flow. Additionally, different inlet water temperatures were examined, revealing that increasing the inlet water temperature leads to a significant rise in the cells' maximum temperature. [ABSTRACT FROM AUTHOR]

The design of an efficient thermal management system for a lithium-ion battery pack hinges on a deep understanding of the cells' thermal behavior. This understanding can be gained through theoretical or experimental methods. While the theoretical study of the cells using electrochemical and numerical methods requires expensive computing facilities and time, the Equivalent Circuit Model (ECM) offers a more direct approach. However, upfront experimental cell characterization is needed to determine the ECM parameters. In this study, the behavior of a cell is characterized experimentally, and the results are used to build a second-order equivalent electrical circuit model of the cell. This model is then integrated with the cooling system of the battery pack for effective thermal management. The Equivalent Circuit Model estimates the internal heat generation inside the cell using instantaneous load current, terminal voltage, and temperature data. By extrapolating the heat generation data of a single cell, we can determine the heat generation of the cells in the pack. With the implementation of the ECM in the cooling system, the coolant flow rate can be adjusted to ensure the attainment of a safe operating cell temperature. Our study confirms that 14% of pumping power can be reduced when compared to the conventional constant flow rate cooling system, while still maintaining the temperature of the cells within safe limits. [ABSTRACT FROM AUTHOR]

As the CMOS technology continuously scales down into the deep submicron regime and approaches the physical limits of minimization, Moore's Law is hindered. The proposed 3-D integrated circuit technology based on through silicon via brings hope. Although 3-D integrated circuits bring many advantages over 2-D integrated circuits, the thermal management challenges still need to be addressed effectively. The through silicon via carry signals while facilitating the thermal transfer of stacked chips due to their high thermal conductivity and offer a potential thermal management solution for 3-D integrated circuits. The through silicon via are structured in arrays to significantly improve heat dissipation. This paper proposes a cellular array structure that offers better heat dissipation capabilities compared to conventional rectangular arrays. First, the through silicon via cellular arrangement is described. Secondly, a method for modelling the equivalent thermal conductivity of through silicon via arrays is proposed. Finally, the excellent performance of the cellular structure on thermal conductivity is verified by a comparative analysis of the thermal characteristics of the through silicon via array in the COMSOL system using finite element method. The results presented in this paper are beneficial for designers to optimize the through silicon via array arrangement and predict the thermal performance of through silicon via arrays. In addition, it provides a reference for 3-D integrated circuit reliability design. [ABSTRACT FROM AUTHOR]

Diamond/aluminium composites have attracted attention in the field of thermal management of electronic packaging for their excellent properties. In order to solve the interfacial problem between diamond and aluminium, a novel process combining pressure infiltration with vacuum-assisted technology was proposed to prepare diamond/aluminum composites. The effect of diamond particle size on the microstructure and properties of the diamond/Al-12Si composites was investigated. The results show that the diamond/Al-12Si composites exhibit high relative density and a uniform microstructure. Both thermal conductivity and coefficient of thermal expansion increase with increasing particle size, while the bending strength exhibits the opposite trend. When the average diamond particle size increases from 45 µm to 425 µm, the thermal conductivity of the composites increases from 455 W·m-1·K-1 to 713 W·m-1·K-1 and the coefficient of thermal expansion increases from 4.97×10-6 K-1 to 6.72×10-6 K-1, while the bending strength decreases from 353 MPa to 246 MPa. This research demonstrates that high-quality composites can be prepared by the vacuum-assisted pressure infiltration process and the thermal conductivity of the composites can be effectively improved by increasing the diamond particle size. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries still remain a cornerstone for the sustainable transportation by the way of its usage in electric vehicles (EVs). However, their optimal performance hinges on maintaining at consistent thermal conditions especially during operation, and at high discharge rates. The present study proposes a novel mini-channel cooling system specifically designed for a 10 Ah lithium-ion pouch cell. This innovative design incorporates cold plates on both battery surfaces for enhanced heat dissipation. In addition, the efficacy of silver (Ag) and copper oxide (CuO) nanofluid coolants by comparing with traditional water cooling in three distinct battery design configurations was also studied. Design 1 and 2 comprises respectively with partially and fully encased cold plates with mini-channels distributed both segmentally and centrally, and Design 3 the present proposed model featuring a fully covered cold plate with a serpentine flow layout for optimized heat transfer efficiency. Extensive computational analysis using ANSYS FLUENT 18.1 software reveals the superiority of Design 3. Notably, this configuration achieved significantly a lower maximum cell temperature (306.7 K and 305.0 K) with 0.25% and 0.5% Ag nanofluid coolants compared to Design 1 and 2, at a discharge rate of 5C. This underscores the potential of silver nanofluids for superior battery thermal management, particularly within the optimized Design 3 framework. These findings offer valuable insights for developing enhanced battery thermal management systems in EVs. [ABSTRACT FROM AUTHOR]

High-performance thermally conductive composites are increasingly vital due to the accelerated advancements in communication and electronics, driving the demand for efficient thermal management in electronic packaging, light-emitting diodes (LEDs), and energy storage applications. Controlling the orderly arrangement of fillers within a polymer matrix is acknowledged as an essential strategy for developing thermal conductive composites. In this study, isotactic polypropylene/GNP (iPP/GNP) composite filament tailored for fused deposition modeling (FDM) was achieved by combining ball milling with melt extrusion processing. The rheological properties of the composites were thoroughly studied. The shear field and pressure field distributions during the FDM extrusion process were simulated and examined using Polyflow, focusing on the influence of the 3D printing processing flow field on the orientation of GNP within the iPP matrix. Exploiting the unique capabilities of FDM and through strategic printing path design, thermally conductive composites with GNPs oriented in the through-plane direction were 3D printed. At a GNP content of 5 wt%, the as-printed sample demonstrated a thermal conductivity of 0.64 W/m · K, which was 1.5 times the in-plane thermal conductivity for 0.42 W/m · K and triple pure iPP for 0.22 W/m · K. Effective medium theory (EMT) model fitting results indicated a significantly reduced interface thermal resistance in the through-plane direction compared to the in-plane direction. This work shed brilliant light on developing PP-based thermal conductive composites with arbitrarily-customized structures. [ABSTRACT FROM AUTHOR]

Thermal management systems using phase change materials (PCMs) can improve heat absorption and increase safe operating times. However, limited research has explored combining multiple PCMs within a system. This study investigates the thermal performance of a two-dimensional heat sink with varied PCM configurations. Simulations tested RT-54, CaCl2.6H2O, anfigd n-Eicosane arranged in different ways at 5 W and 7.5 W. Key results show CaCl2.6H2O with n-Eicosane increased the time to reach 40°C by 186% compared to CaCl2.6H2O alone at 5 W. Pairing CaCl2.6H2O and RT-54 improved time to 40°C by 425%. Increased power amplified these effects. The density and latent heat fusion of PCMs were critical factors. This demonstrates combining certain PCMs extends safe operating times more than using a single material. These optimal configurations can guide thermal management system design for electronics and other applications. [ABSTRACT FROM AUTHOR]

Aiming at the problem of high battery heat generation during the super fast-charging process of electric vehicle fast-charging power batteries, this study designs a fast-charging battery thermal management system based on the refrigerant direct cooling architecture. In order to use the refrigerant of refrigerant to cool the battery quickly. Firstly, the study constructs the heat generation model of the power battery, the calculation model of the battery thermal management system, and builds the experimental device. Secondly, theoretical simulations and experimental studies were conducted for low-temperature fast-charging and high-temperature fast-charging operating conditions. The experimental results show that the designed battery thermal management system has good cooling effect and temperature uniformity. [ABSTRACT FROM AUTHOR]

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The dielectric loss of Cu with high thermal conductivity is large at high frequency, which cannot meet the performance requirements in high-integrated circuits. There is an urgent need for materials to reduce its dielectric loss. In this paper, the thermal conductivity and dielectric properties of the AlN coating-Cu substrate system were controlled by changing the N2 pressure. The results showed that the crystallinity of hcp-AlN in AlN coating increased significantly when the proportion of N2 pressure was increased. With the increase of the N2 pressure, the particle size on the surface and the roughness of the coating improved. The AlN coating prepared at high N2 pressure had high dielectric constant and low dielectric loss at high frequency compared to those of the coatings prepared at low N2 pressure. At the same time, the AlN coating prepared under high N2 pressure on the Cu substrate did not decrease the thermal conductivity of Cu substrate. The AlN-Cu system prepared in this paper had high thermal conductivity and good dielectric properties, providing theoretical guidance for integrated circuit packaging and capacitor applications. [ABSTRACT FROM AUTHOR]

The cooling system is the auxiliary equipment that consumes the most energy in a data center, accounting for about 30 to 50% of the total energy consumption. In order to effectively reduce the energy consumption of a data center, it is very important to improve the heat exchange efficiency at the chip level. Compared with air cooling, single-phase cold plate liquid cooling, and immersion liquid cooling, the flat loop heat pipe (FLHP) is considered to be a better chip-level cooling solution for data centers. It has extremely high heat transfer efficiency and heat flux variability, and it can avoid the operation risk caused by liquid entering the server. In this paper, a FLHP with an evaporator designed with a "Tesla valve" flow channel configuration is developed. Experiments on the FLHP are carried out, focusing on the installation angles and cooling condition factors. The results show that an inclination angle of 20° is the critical point of the influence of gravity on the performance of the FLHP; to ensure good operation of the FLHP, the installation angle should be greater than 20°. The equivalent heat transfer coefficients of the FLHP condenser under different cooling conditions are calculated. It is found that water cooling can provide higher cooling heat transfer coefficients with lower energy consumption and operating noise. Additionally, the heat transfer limit, operating temperature uniformity, and start-up stability of the FLHP are significantly improved under water cooling conditions. The maximum heat load of the FLHP is up to 230 W, and the temperature difference of the evaporator surface can be controlled within 0.5 °C, under 20 °C water cooling. Finally, using the FLHP for thermal management of the chip, its heat transfer efficiency is 166 and 41% higher than that of air cooling and water cooling, respectively. [ABSTRACT FROM AUTHOR]

Air conditioning has become a necessity in people's daily life. The performance of the compressor determines the energy efficiency ratio of this electrical equipment, but the heat generated during the operation of its internal core power components will greatly limit its performance release, so it is urgent to carry out research on the heat dissipation of power devices. In this work, we explore the application of thermoelectric coolers (TECs) in the field of power device heat dissipation through finite element simulation. First, we geometrically modeled the structure and typical operating conditions of core power devices in air conditioners. We compared the temperature fields in air-cooling and TEC active cooling modes for high-power-consumption power devices in a 319 K operating environment. The simulation results show that in the single air-cooling mode, the maximum temperature of the 173.8 W power device reached 394.4 K, and the average temperature reached 373.9 K, which exceeds its rated operating temperature of 368.1 K. However, the maximum and average temperature of the power device dropped to 331.8 K and 326.5 K, respectively, at an operating current of 7.5 A after adding TECs, which indicates that TEC active cooling has a significant effect on the temperature control of the power device. Furthermore, we studied the effect of the TEC working current on the temperature control effect of power devices to better understand the reliability of the TECs. The results show that TECs have a minimum working current of 5 A, which means it has no significant cooling effect when the working current is less than 5 A, and when increasing the current to 10 A, the average temperature of the power device can be reduced to 292.9 K. This study provides a meaningful exploration of the application of TECs in chip temperature control and heat dissipation, providing a new solution for chip thermal management and accurate temperature control. [ABSTRACT FROM AUTHOR]

Thermal conductive materials with low dielectric constant under high frequencies play an important role in high-power integrated circuits packaging. The application of Cu in the packaging substrates is limited due to the high dielectric constant. In this paper, the AlN coatings were deposited on the Cu substrates to maintain the high thermal conductivity and obtain excellent electrical properties for the first time. The microstructure, thermal conductivity and electrical properties of the AlN/Cu systems were adjusted by duty cycles. The results show that improving the duty cycle reduced the hcp-AlN (002) preferred orientation degree of the coatings. The growth structure of the coatings could be regulated by increasing the duty cycle, which induced the grain and particle size first increasing and then decreasing. AlN/Cu systems improved the thermal conductivity of Cu. All coatings show far higher resistivity than Cu and 0.006–0.24 low dielectric loss. The minimum dielectric constant (5.6) of the coating at 2000 kHz frequency was obtained. The AlN/Cu systems in this paper realize high thermal conductivity and excellently dielectric properties, meeting the application in high-power integrated circuit packaging. [ABSTRACT FROM AUTHOR]

The operating temperature of a battery energy storage system (BESS) has a significant impact on battery performance, such as safety, state of charge (SOC), and cycle life. For weather-resistant aluminum batteries (AlBs), the precision of the SOC is sensitive to temperature variation, and errors in the SOC of AlBs may occur. In this study, a combination of the experimental charge/discharge data and a 3D anisotropic homogeneous (Ani-hom) transient heat transfer simulation is performed to understand the thermal effect of a novel battery system, say an aluminum-ion battery. The study conducts a turbulence fluid dynamics method to solve the temperature distribution of the battery rack, and the entropy generation method analyzes the heat generation of AlB during the charging/discharging process. The AlB is modeled by a second-order Thevenin equivalent circuit to estimate the status of the battery. An extended Kalman filter is applied to obtain the accurate SOC for monitoring the battery cell. The current study conducts the Galvanostatic Intermittent Titration Technique (GITT) on aluminum-ion batteries under different operation temperatures: 25 °C, 40 °C, 60 °C, and 80 °C. According to the sensitivity analysis of the SOC, the temperature sensitivity tends to or greater than one, S T ≥ 1 , while the operation temperature is above 40 °C, and the SOC modification of EKFtmep estimator improves the battery state of charge in the error range below 1%. [ABSTRACT FROM AUTHOR]

Aiming at the thermal safety and inconsistency caused by the high temperature of lithium‐ion (Li‐ion) battery, a cooling structure embedded with a flat aluminum heat pipe (FAHP) for a Li‐ion battery module is proposed. The three‐dimensional thermal model of the FAHP module is established by considering regionalized thermal radiation. The thermal characteristics of the module are compared with four progressive cooling schemes, and the temperature performance affected by different convection (hconv) and radiation (hrad) heat transfer coefficients are analyzed. Results show that, the thermal model with the thermal radiation is more precise than that without the thermal radiation under the natural convection. Adding FAHPs can effectively reduce the maximum temperature (Tmax) and the maximum temperature difference (ΔTmax,pack) of the FAHP module. Especially adding FAHPs with fins, even at 3C discharging, the average cooling performance can be improved by 33.3%, 25.0%, and 14.4% than that of natural convection, aluminum plates sandwiched between cells and FAHPs with no fins, respectively. Meanwhile, the decrease in rates of Tmax and ΔTmax,pack are gradually increasing with the increasing of hrad, but decreased with the increasing of hconv. When 5 W·m−2·K−1 ≤ hconv ≤ 35 W·m−2·K−1, the average ratio of radiation heat dissipation to total heat dissipation (η) is 35.7%, but when hconv > 55 W·m−2·K−1, η is less than 1.5%. [ABSTRACT FROM AUTHOR]

Metal hydrides are a class of materials that can absorb and release large amounts of hydrogen. They have a wide range of potential applications, including their use as a hydrogen storage medium for fuel cells or as a hydrogen release agent for chemical processing. While being a technology that can supersede existing energy storage systems in manifold ways, the use of metal hydrides also faces some challenges that currently hinder their widespread applicability. As the effectiveness of heat transfer across metal hydride systems can have a major impact on their overall efficiency, an affluent description of more efficient heat transfer systems is needed. The literature on the subject has proposed various methods that have been used to improve heat transfer in metal hydride systems over the years, such as optimization of the shape of the reactor vessel, the use of heat exchangers, phase change materials (PCM), nano oxide additives, adding cooling tubes and water jackets, and adding high thermal conductivity additives. This review article provides a comprehensive overview of the latest, state-of-the-art techniques in metal hydride reactor design and heat transfer enhancement methodologies and identifies key areas for future researchers to target. A comprehensive analysis of thermal management techniques is documented, including performance comparisons among various approaches and guidance on selecting appropriate thermal management techniques. For the comparisons, the hydrogen adsorption time relative to the reactor size and to the amount of hydrogen absorbed is studied. This review wishes to examine the various methods that have been used to improve heat transfer in metal hydride systems and thus aims to provide researchers and engineers working in the field of hydrogen storage with valuable insights and a roadmap to guide them to further explore the development of effective thermal management techniques for metal hydrides. [ABSTRACT FROM AUTHOR]

PV-based mini-grids are identified as a feasible and, often, only economically viable option for the electrification of Kenyan remote and scattered rural areas, where connection to the national grid is challenging, and the related costs are high, if not prohibitive. This paper presents the analysis of typical Kenyan PV mini-grids by using some results of the work in the project "Reliable, Efficient and Sustainable Mini-Grids for Rural Infrastructure Development in Kenya (RESILIENT)". After presenting average annual and seasonal daily load profiles of residential and small commercial mini-grid customers identified from the measured demands, the paper introduces the main mini-grid components and their models, including a simplified, but reasonably accurate, model of a mini-grid battery storage system based on the manufacturer's charge–discharge curves. All mini-grid components are assembled in a scalable and easily reconfigurable simulation model of an actual Kenyan PV mini-grid, and they are implemented for the evaluation of PV mini-grid performance and the potential for expansion and connection of additional residential and small commercial customers. During the validation of the developed simulation model using available measurement data, an empirical approach for adjusting the PV system output power is specified for a more accurate match with the measurements. The presented results indicate the importance of the information on the actual control algorithms and control settings of the mini-grid energy management systems, on the thermal dependencies and characteristics of both PV generation system and battery storage system, and on the availability of on-site measurements of temperature and input solar irradiance. The developed PV mini-grid model can be used for further analyses, such as to study the techno-economic performance of different mini-grid configurations, to identify the optimal sizing of mini-grid components, and to specify efficient control and operation schemes based on the locally available resources. [ABSTRACT FROM AUTHOR]

Applying the recycled power battery to automatic guided vehicles can greatly reduce system cost and prolong the life cycle of the battery. However, the consistency of recycled power batteries is poor, and the imbalance of battery voltage will occur during the charging or discharging process. Therefore, a double-switch single-transformer integrated equalizer is proposed to balance automatic guided vehicles in both charging and discharging operations. The equalizer's multiwinding transformer shares the dc–dc converter's inductor, and the secondary side generates current by utilizing the current ripple on the primary windings. The battery string is balanced by the multiwinding transformer, without extra switches, when the circuit works in charging and discharging mode. A prototype for four battery cells is built to verify the proposed equalizer and its dynamic balance conditions, and a comparison with existing equalizers is presented. The results show that the system in both modes can realize the automatic balance without affecting the function of the dc–dc converter. The proposed circuit requires fewer components than the existing bidirectional integrated equalizer. [ABSTRACT FROM AUTHOR]

Due to the continuous high traction power impact on the energy storage medium, it is easy to cause many safety risks during the driving process, such as triggering the aging mechanism, causing rapid deterioration of the battery performance during the driving process and even triggering thermal runaway. Hybrid energy storage is an effective way to solve this problem. The ultracapacitor is an energy storage device that has high power density, which can withstand high instantaneous currents and can be charged and discharged quickly. By combining batteries and ultracapacitors in a hybrid energy storage system, energy sources with different characteristics can be combined to take advantage of their respective strengths and increase the efficiency and lifetime of the system. The energy management strategy plays an important role in the performance of hybrid energy storage systems. Traditional optimization algorithms have difficulty improving the flexibility and practicality of applications. In this paper, an energy management strategy based on reinforcement learning is proposed. The results indicate that the proposed reinforcement method can effectively distribute the charging and discharging conditions of the power supply and maintain the SOC of the battery and, at the same time, meet the power demand of working conditions at the cost of less energy loss and effectively realize the goal of optimizing the overall efficiency and effective energy management strategy. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) proved to be valuable and drew the attention of numerous scientists striving to establish novel techniques to minimize energy consumption and expand heat storage; yet a number of challenges hampered their research. This paper provides an overall overview on how to overcome those constraints by adapting nano-enhanced phase change materials, the motivation behind their investigation, their advantages, area of applications, and their impact on thermal management and storage equipment. Recent computational and experimental studies have revealed that nanoparticles are extremely useful in terms of improving the thermo-physical properties of PCMs, allowing nano-PCMs, mainly nano-paraffin, to have a major positive influence on thermal concepts at the economical, ecological, and effectiveness levels. In this context, nano-enhanced PCMs are now able to store and release large amounts of heat in short intervals of time, which is relevant to thermal storage systems and contributes to augmenting and boosting their efficiency. It also improves the thermal performance of cooling and heating systems in buildings and regulates the operating temperature of PV systems, electronic components, and batteries. [ABSTRACT FROM AUTHOR]

As a representative electrochemical energy storage device, supercapacitors (SCs) feature higher energy density than traditional capacitors and better power density and cycle life compared to lithium-ion batteries, which explains why they are extensively applied in the field of energy storage. While the available reviews are mainly concerned with component materials, state estimation, and industrial applications, there is a shortage of understanding of thermal behaviors and thermal management systems of SCs, which makes this review a timely aide for fulfilling this gap. This review introduces the energy storage mechanisms of SCs, followed by descriptions of current investigations of thermal behaviors. This covers the aspects of heat generation rates for electric double-layer capacitors (EDLCs) and hybrid supercapacitors (HSCs), together with reviewing existing experimental methods to measure and estimate heat generation rates, as well as comparative assessments of multiple heat generation rate models and research on thermal runaway. In addition, there are also overviews of current efforts by researchers in air cooling systems, liquid cooling systems, phase change material cooling systems, and heat pipe cooling systems. Finally, an in-depth discussion is provided regarding the challenges and future work directions for SCs in thermal behaviors and thermal management systems. [ABSTRACT FROM AUTHOR]

Because of their fast-switching speed and small die size, gallium-nitride high electron mobility transistors are challenging to package for low parasitic inductance and high heat dissipation in power electronics applications. In this article, a packaging technique was developed for making half-bridge modules of a 650 V, 150 A enhancement-mode gallium-nitride power transistor. The package consists of the device chips interconnected between a printed circuit board and an aluminum-nitride direct-bonded copper substrate. The dice are bonded on the insulated ceramic substrate by silver-sintering to ensure high thermal performance and joint reliability. The source, drain, and gate pads are connected by silver-sintering gold-plated pins or silver rods, which are aligned by holes or grooves in the circuit board. For electrical insulation and mechanical robustness, the space surrounding the device is filled by injecting and curing an underfill polymer. Electrical and thermal simulations of the package show that the half-bridge module has a 1.122 nH power-loop inductance, and 0.099 °C/W junction-to-case thermal resistance. Packages of the half-bridge module were fabricated, and their static and dynamic performances were characterized. [ABSTRACT FROM AUTHOR]

• The TRP model of NCM 811 and LFP batteries is established, the model parameters are determined, and the model accuracy is evaluated experimentally. • The TRP models of typical AB battery configurations are established, and their TRP characteristics are obtained through simulation and experiments. • The typical AB battery configurations are optimized to achieve both high energy density and high safety, providing valuable references for the design of hybrid-cell battery packs. Thermal runaway (TR) and its propagation (TRP) in lithium-ion batteries are critical safety concerns. The emergence of hybrid battery packs, combining different battery types (referred to as AB batteries), has gained significant attention as a potential solution to enhance battery safety. However, there is a lack of evaluation regarding the TRP characteristics of these configurations. In this study, various AB battery configurations, incorporating NCM 811 and LFP batteries, are examined through simulations and experiments to investigate their TRP behavior. The findings reveal that: (1) A well-designed AB battery configuration can effectively suppress TR, achieving a balance between high energy density and safety. The high TR trigger temperature and specific heat capacity of LFP batteries play a vital role in impeding TRP. (2) The 8L8L battery configuration successfully suppresses TRP, while the 88L88 configuration requires the addition of heat-insulating sheets for effective TRP suppression. (3) Increasing the number of LFP batteries proves to be an effective approach in preventing TRP. For instance, configurations such as 88LL88 and 888888LL888888 demonstrate no occurrence of TRP. The study concludes by summarizing the TRP characteristics of different AB battery configurations, offering valuable insights for the design of high-safety battery packs. [ABSTRACT FROM AUTHOR]

To design such a hybrid battery thermal management system (BTMS), it is crucial to establish a practical and realistic approach from the point of view of: i. simulated operating conditions, ii. assumed materials/compounds, iii. Fast-charging performance test. To avoid oversizing, this work considers the World Harmonized Light-duty Vehicle Test Procedure Class 3 (WLTP3) driving cycle, instead of constant charge/discharge rates. Power requirements of a medium-sized vehicle during this WLTP3 cycle have been used to estimate the heat generated by the proposed battery module (18650 NMC cylindrical cells, hexagonal arrangement). This allows the minimum mass required by the phase change materials (PCM) to maintain the battery module at a given temperature threshold to be determined. Once this PCM mass requirement was established, a comprehensive optimization of the key thermal properties that characterize PCMs was carried out, investigating carbon-based additives (CBAs) to improve the low thermal conductivity of PCMs. The results show that the proposed approach can sustain up to 10 consecutive WLTP3 driving profiles without the need for additional energy input. This approach passively minimizes energy consumption during operation and absorbs up to 27 % of the heat emitted by the cell during fast charging, reducing the liquid cooling power requirement. • A hybrid BTMS composed of ssPCMs and liquid cooling is optimized. • WLTP3 drive cycle used instead of constant rates are used to size PCM thickness. • Hexagonal cell arrangement ensures minimum space use in battery packs. • Optimal properties: Cp eff ∼85 kJ/(kg·K) and k eff ∼8 W/(m·K) with 20 wt% additive. • SsPCM holder absorbs 27 % of battery heat during fast charging. [ABSTRACT FROM AUTHOR]

Battery safety design is important to consider from the individual Li-ion cell to the level of the macro-system. On the macro-level, failure in one single cell can lead to propagation of the thermal runaway and rapidly set a whole battery pack on fire. Factors that can impact the propagation outcome, such as cell model/chemistry and electrical connection are here investigated using a combination of measurements. Several abusive tests were conducted, combining two different cell models (Molicel P42A and LG M50, both 21700s) in series and parallel connections (16 tests per configuration). Overall, a propagation outcome of 56% was measured from the 32 conducted tests, a minimum temperature of 150 °C was required to initiate propagation, and the fastest propagation occurred in 123 s. Temperature measurements were higher in series connected cells, initiating the discussion of cell chemistry and internal resistance on this effect. The difference in current-flow during thermal runaway in series and parallel connections, and how this can affect the temperature evolution is further discussed. Spatio-temporal mapping of X-ray radiography allowed us to derive the speed of thermal runaway evolution inside the battery and has shown that series connected cells, in particular P42A, occur faster. It was further observed that deviant sidewall behaviors such as temperature-induced breaches and pressure-induced ruptures occurred in P42As only respective nail-penetrated cells only. • 56% chance of Li-ion battery failure propagation for abusive test scenarios conducted. • Spatio-temporal mapping of Li-ion battery failure from High-Speed X-ray Imaging. • Cell chemistry and electrical connection influence failure temperature and speed. [ABSTRACT FROM AUTHOR]

[Display omitted] Polymer-based dielectrics with high thermal conductivity and superb dielectric properties hold great promising for advanced electronic packaging and thermal management application. However, integrating these properties into a single material remains challenging due to their mutually exclusive physical connotations. Here, an ideal dielectric thermally conductive epoxy composite is successfully prepared by incorporating multiscale hybrid fillers of boron nitride microsphere (BNMS) and silicon dioxide coated silicon carbide nanoparticles (SiC@SiO 2). In the resultant composites, the microscale BNMS serve as the principal building blocks to establish the thermally conductive network, while the nanoscale SiC@SiO 2 as bridges to optimize the heat transfer and suppress the interfacial phonon scattering. In addition, the special core–shell nanoarchitecture of SiC@SiO 2 can significantly impede the leakage current and generate a great deal of minicapacitors in the composites. Consequently, favorable thermal conductivity (0.76 W/mK) and dielectric constant (∼8.19) are simultaneously achieved in the BNMS/SiC@SiO 2 /Epoxy composites without compromising the dielectric loss (∼0.022). The strategy described in this study provides important insights into the design of high-performance dielectric composites by capitalizing on the merits of different particles. [ABSTRACT FROM AUTHOR]

Medium-voltage silicon carbide (SiC) power modules are a critical component in grid-bound power conversion systems, and the packaging of these modules dictates the performance and reliability of the systems. One of the key issues for packaging the modules is managing the tradeoff between heat dissipation and insulation. To improve thermal performance without sacrificing insulation, a 10-kV SiC full-wave diode rectifier was designed and fabricated by incorporating double-sided cooling and wirebond-less interconnection and by utilizing thin alumina direct-bond copper substrates. To ensure that the substrates met insulation requirement, triple points on the substrates were coated by a nonlinear resistive polymer-nanoparticle composite to reduce electric field concentration. The nonlinear resistive coating increased the partial discharge inception voltage of the substrate with 0.5-mm thick alumina to 17.3 kV, an 84% improvement over that of the substrate without the coating. Electrical and thermal simulations of the module showed a low power loop inductance of 3.51 nH and a low junction-to-case thermal resistance of 0.114°C/W. The feasibility of the packaging techniques was demonstrated from successful fabrication and functional testing of the packagedmodule. [ABSTRACT FROM AUTHOR]

The feasibility of the future more-electric, hybrid-electric, and all-electric aircraft configurations will depend on a good understanding of thermal aspects early in the design. However, thermal analysis of aircraft equipment bays is typically performed at later design stages to validate if the design meets the minimal certification requirements rather than to optimize the cooling strategy. The presented work aims to provide new insight into thermal aspects in typical aircraft equipment bays. In particular, system thermal interactions, such as radiation, play a more significant role in tightly packaged bays, such as avionics bays. This paper investigates the influence of radiation on the overall system heat dissipation in two representative avionics bays. Using Computational Fluid Dynamics (CFD) simulation, combined with an analytical approach, the authors analyze the impact of several parameters, such as varying mass flow rates and distances between adjacent systems, on their thermal interaction. The results suggest that the radiative effects must be considered when the gap distance between the systems is larger than 0.1 m, the flow rate between two systems is not strong enough to have high convective heat exchanges, when the systems of interest are hidden by other systems from the ventilation sources, and when the system's internal heat dissipation is significant. Overall, this paper's results will contribute enhance conceptual design methods, such as the previously developed Thermal Risk Analysis, and help optimize thermal management strategies for future aircraft. [ABSTRACT FROM AUTHOR]

High-performance composites with a resin matrix are urgently required for electronic packaging due to their low dielectric constant, outstanding high temperature resistance, excellent corrosion resistance, light weight and easy molding. In this work, hollow-glass-microsphere (HGM)-filled fluorinated-phthalonitrile (PBDP) composites, with filler contents ranging from 0 to 35.0 vol.%, were prepared in order to modify the dielectric properties of the phthalonitrile. Scanning electron microscopy (SEM) observations indicate that the modified HGM particles were uniformly dispersed in the matrix. The PBDP/27.5HGM-NH2 composite demonstrates a low dielectric constant of 1.85 at 12 GHz. The 5% thermogravimetric temperature (T5) of composites with silanized HGM filler (481–486 °C) is higher than the minimum packaging-material requirements (450 °C). In addition, the heat-resistance index (THRI) of PBDP/HGM-NH2 composites reached as high as 268 °C. the storage modulus of PBDP/HGM-NH2 composites were significantly increased to 1283 MPa at 400 °C, an increase by 50%, in comparison to that of PBDP phthalonitrile resin (857 MPa). The excellent dielectric and thermal properties of the present composites may pave a way for comprehensive applications in electronic packaging and thermal management for energy systems. [ABSTRACT FROM AUTHOR]

The pumped two-phase cooling method is a practical way to dissipate heat from the battery module. The operating parameters of the cooling system should be investigated thoroughly to improve the performance of the battery thermal management system (BTMS). However, the previous BTMS designs only explored the thermal performance and ignored the electrical performance in the battery module. This study designed a pumped two-phase cooling BTMS with the refrigerant of R1233zd. An electrothermal coupled model was established for a series-connected battery module to predict thermal and electrical behavior. The results showed that the pumped two-phase cooling system could obtain excellent cooling performance with low system pressure under 2C discharging condition. The average temperature of the module and the temperature difference among cells could be maintained under 40 °C and 5 K under a 2C discharging rate. A lower saturation temperature, higher mass flux, and higher subcooling degree could enhance heat dissipation for the cooling system based on R1233zd. An increase in the saturation temperature and a decrease in the subcooling degree could enhance the temperature uniformity within the module. The battery consistency was mainly dominated by the temperature difference and deteriorated with a lower average temperature in the pack. The research outcome of this paper can guide the design and optimization of the pumped two-phase cooling BTMS. [ABSTRACT FROM AUTHOR]

This paper proposes two non-isolated step-down DC–DC converters based on the type-A three-state switching cell (3SSC-A), resulting in an alternative to the buck and buck-boost classical converters, respectively. The proposed topologies are part of a group of unexplored converters that employ the 3SSC-A, which has the advantages of 3SSC-based converters, such as high power density, reduced current stress on the semiconductors and suitable thermal loss distribution. In this regard, a complete static analysis is performed, including a detailed study of all semiconductor voltage and current efforts and developing loss models for each one. Moreover, by using simulation models, AC sweep analyses validate the dynamic frequency response of each converter's small-signal models, and PI-based output–voltage closed-loop controllers are duly designed. Finally, the topologies are experimentally validated through the implementation of adequately designed prototypes, achieving efficiency values greater than 91% under several output power rates varying from 50% to 100%. [ABSTRACT FROM AUTHOR]

This article presents the design and analysis of a double-side-cooled printed circuit board (PCB) embedded silicon carbide (SiC) MOSFET half-bridge package with low loop inductances and an integrated gate driver. The 1.2 kV SiC MOSFET dies used in the half-bridge package are embedded in the PCB using AT&S's patented technique. The dies are cooled and electrically connected to traces in the PCB through copper-filled microvias. The design methodology accounts for both electrical and thermal performance, limiting the power-loop inductance to 2.3 nH and the maximum package temperature to less than the 175 °C limit. The integration of the gate drive circuitry allows for a high power density and 2.2 nH gate-loop inductances. At 0.12 K/W, the measured junction-to-case thermal resistance with double-sided cooling is 57% lower than that of a TO-247 package. Under similar operating conditions, the PCB-embedded half-bridge package also achieves a 5.6 times lower voltage overshoot and a 0.5% higher peak efficiency than a TO-247-based half-bridge. This article reports the first demonstration of PCB-embedded 1.2 kV SiC MOSFET packages in buck, boost, and ac–dc converters. The prototype three-phase ac–dc converter for an electric vehicle on-board charger is composed of six PCB-embedded half-bridge packages and achieves an efficiency of 98.2% and a power density of 182 W/in3. [ABSTRACT FROM AUTHOR]

This article describes the design and performance of a dielectric fluid cooling concept for automotive power electronics. The concept combines a low-thermal-resistance package (which eliminates metalized ceramic substrates) with a high-performance convective cooling strategy (slot jets impinging on finned surfaces). Modeling was first used to design the cooling system to maximize thermal performance and minimize pumping power. A prototype was then fabricated, and experiments were conducted to validate the model predictions using three fluids at various fluid flow rates (16.7 cm3/s [1 L/min] to 68.3 cm3/s [4.1 L/min]) and inlet temperatures (30 °C and 70 °C). The final design was compact (120-cm3 total volume, including heat exchanger and conceptual power modules) and cooled 12 devices (e.g., silicon carbide [SiC]). The validated model was then used to predict the junction-to-fluid thermal resistance and pumping power for various conditions, including −40 °C fluid temperature. The results predict thermal resistance values as low as 19 mm2·K/W is possible using the dielectric fluid cooling approach. The dielectric fluid cooling system is predicted to provide thermal resistance and pumping power values that are approximately 56% and 90% lower, respectively, compared to an automotive power electronics cooling system. Moreover, the dielectric fluids can be used for direct cooling of the bus bars, which can be an effective capacitor and gate driver cooling strategy and enable the use of new driveline fluids tailored for this application. [ABSTRACT FROM AUTHOR]

Sodium-sulfur (NaS) batteries are a promising energy storage technology that features high energy density, high cycle life, and no self-discharge. One of the cell design considerations that can affect the performance and construction of NaS batteries is cell geometry. While the planar geometry has advantages in power output, cell packing, ease of assembly, and thermal management, it has thermo-mechanical issues in sealing, which makes it less commercialized than the tubular geometry. In this work, the first multiphysics model of a NaS cell with a planar geometry was developed by extending an existing multiphysics model for a NaS cell with a tubular geometry. A previously developed multiphysics model for the tubular NaS cell was first adapted into COMSOL Multiphysics®. The model's results were then validated against experimental discharge profiles and surface temperatures. After this, a planar NaS cell was simulated using the dimensions of an experimental planar cell, with the mass, heat, and charge transfer equations and parameters previously used in the tubular multiphysics model. The results from the planar model were then validated through comparison to experimental discharge profiles for a planar cell. The developed model can be used in future research and development of NaS batteries by comparing performance parameters of the planar geometry such as discharge profiles, energy densities, and temperatures with a multiphysics model of the tubular NaS battery. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride (hBN) has been incorporated, as an active filler, in a customized silicone matrix to obtain high thermal conductivity composites, maintaining high flexibility and low dielectric permittivity, which are of interest for heat dissipation in energy storage systems (e.g., batteries or supercapacitors) and electronics. By the proper processing of the filler (i.e., hydrophobization with octamethylcyclotetrasiloxane and ultrasonic exfoliation) and its optimal loading (i.e., 10 wt%), composites with thermal conductivity up to 3.543 W·m−1·K−1 were obtained. Conductive heat flow (−280.04 W), measured in real heating–cooling conditions, proved to be superior to that of a commercial heatsink paste (−161.92 W), which has a much higher density (2.5 g/cm3 compared to 1.05 g/cm3 of these composites). The mechanical and electrical properties are also affected in a favorable way (increased modulus and elongation, low dielectric losses, and electrical conductivity) for applications as thermal management materials. [ABSTRACT FROM AUTHOR]

Accurate measurements of the junction-to-case thermal resistances of power devices or module packages are necessary for validating the thermal design of the package as well as of the entire converter system. Although accurate measurements can be obtained for Si and SiC packages by the JESD51-14 standard, no standard has been established for gallium nitride (GaN) packages. A main reason for this shortcoming is the lack of accurate techniques for measuring the device's junction temperature. In this letter, a custom package of a (650 V, 150 A) eGaN high-electron mobility transistor with two gate pads was fabricated, and then its junction-to-case thermal resistance was measured by combining two techniques to improve the accuracy: using the device's gate-to-gate electrical resistance as the temperature-sensitive electrical parameter; and measuring the thermal resistance as a function of added layers of thermal interface materials. The first gives a sensitivity of 4.7 mΩ/°C and is instantaneous and immune to any transient behavior of the device. The second eliminates the need for accurate measurement of the case temperature. The package's junction-to-case thermal resistance was determined by extrapolating the discrete thermal resistance data points in the plot to zero layer of thermal interface. An analytical expression was derived to guide the extrapolation and was validated by finite-element analysis simulations. The measurement procedure was tested using two different thermal interface materials. The difference between the two experimental measurements was within 24%, and both are in good agreement with the simulated result. [ABSTRACT FROM AUTHOR]

Since the wide application of virtual synchronous generators (VSGs), the power grid faces great challenges in the safe and stable operation due to their limited thermal capacity and weak anti-disturbance ability. During transient period, for example, a fault occurs in the transmission line, the VSG may lose the transient angle stability and provoke the current hard limit. Even if the fault is cleared by tripping of line, it still faces the problem of instability and voltage dips. To address this problem, in this paper, the post-fault large-signal model of VSG is derived first via the travelling waves based fault information acquisition. Subsequently, with the effect of both active and reactive power loops taken into account, a two-stage simultaneous control scheme is proposed for improving the transient stability of VSG, while considering the current limitation during fault state and voltage support after fault clearance. This method is fulfilled by mode switching and an additional feedback control based on the fault signal. Finally, the effectiveness of the proposed method under both symmetrical and asymmetrical faults is verified. Moreover, the application of the proposed method in a multiple VSGs system is also verified. Besides, the robustness to parameter mismatch and the feasible operating region for the method are discussed. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) power modules are attractive in many applications due to the superiority of their semiconductor characteristics. However, power modules are subjected to repetitive thermo-mechanical stress caused by the mismatch of the coefficient of thermal expansion between different layers of materials. Moreover, the relatively smaller die size of SiC chips makes the heat flux increase significantly, which brings new challenges to the thermal management and reliability of SiC power modules. To tackle these challenges, this article proposes a new thermal enhanced packaging method based on vapor chamber (VC) phase change heat spreader (PCHS) for SiC power modules, achieving the advantages of high thermal conductivity, low weight, low cost, and low thermal stress. In this new design, SiC mosfet bare dies are directly soldered on the top of VC-PCHS, which not only act as heat spreaders but also conduct the drain current of mosfets. The integrated VC-PCHS is optimized based on thermal and thermomechanical performance. An SiC power module prototype directly integrated with VC-PCHS is built using a new fabrication process. Both the simulations and experiments demonstrate significant improvements in thermal and thermomechanical performance. The modules integrated with VC-PCHS can operate under 200 W of power dissipation per die (632 W/cm2) without exceeding the maximum rated junction temperature. This article reveals the potential of directly integrating phase change cooling components inside power modules, providing a new solution to improve the thermal performance and reliability of SiC power modules without adding complexity and energy consumptions to external cooling systems. [ABSTRACT FROM AUTHOR]

Phonon Boltzmann transport equation (BTE) is a key tool for modeling multiscale phonon transport, which is critical to the thermal management of miniaturized integrated circuits, but assumptions about the system temperatures (i.e., small temperature gradients) are usually made to ensure that it is computationally tractable. To include the effects of large temperature non-equilibrium, we demonstrate a data-free deep learning scheme, physics-informed neural network (PINN), for solving stationary, mode-resolved phonon BTE with arbitrary temperature gradients. This scheme uses the temperature-dependent phonon relaxation times and learns the solutions in parameterized spaces with both length scale and temperature gradient treated as input variables. Numerical experiments suggest that the proposed PINN can accurately predict phonon transport (from 1D to 3D) under arbitrary temperature gradients. Moreover, the proposed scheme shows great promise in simulating device-level phonon heat conduction efficiently and can be potentially used for thermal design. [ABSTRACT FROM AUTHOR]

Double-sided cooling based on planar packaging method features better thermal performance than traditional single-sided cooling based on wire bonds. However, this method still faces thermal and electrical challenges in multichip SiC power modules. Specifically, one is severe thermal coupling among parallel bare dies, and the other is unbalanced current sharing due to unreasonable layout design. This article aims to explore the potentials of SiC power devices in power module, which are higher current capability and reliability. The proposed packaging method is called interleaved planar packaging and can get rid of the optimizing contradiction between thermal and electrical performance. In this packaging method, there are two functional units: interleaved switch unit and current commutator structure. Benefited from the two units’ electromagnetic and thermal decoupling effects, the interleaved power module features low loop inductance, balanced current, low coupling thermal resistance, and even thermal distributions. A 1200 V 3.25 mΩ half-bridge SiC power module based on interleaved planar packaging is fabricated and tested to verify this method's superiority. [ABSTRACT FROM AUTHOR]

In this article, the benchmark drift of micromachined thermal wind sensor due to the packaging asymmetry has been analyzed and compensated. For the ideal wind sensors with symmetric packaging, the benchmark does not vary with speed and direction. However, for the real sensors, especially for handmade ones, packaging asymmetry problems are usually inevitable. Consequently, benchmark drifts with wind because of different thermal distribution in each direction, which was verified by the proposed lumped parameters model. The real sensors were tested in a wind tunnel and results showed the benchmark drift as well. The contribution of this work lies in the establishment of the equation of benchmark dependent on wind speed, which can predict benchmark value under different wind speeds by calibration at zero wind speed. This compensation method is extremely simple and convenient for industrial production. After compensation, the relative wind speed errors are reduced from 46 to 8% up to 30 m/s, and the wind direction errors are reduced from 30° to 7° over the full range of 360°. [ABSTRACT FROM AUTHOR]

In recent years, with the development of wireless communication systems and intelligent auxiliary equipment, the development of various wireless sensors has attracted more and more scientific and commercial attention. A new type of LC (Lenz (inductor) – Capacitor) wireless sensor was designed and fabricated using Low Temperature Co-fired Ceramics (LTCC) technology, including the advantages of low-cost wireless sensing of radio frequency (RF) communications and high operating temperature, miniaturisation, low weight, excellent thermal management, and multilayer printed circuit board of LTCC technology. LTCC technology offers functionalities such as high/low permittivity, low dielectric loss in a single multilayer package and multi-functional features by integration and interconnections. It also offers the highest interconnect density for the fabrication of 3D structures with multilayer additive fabrication of ceramic 2D sheets. In this article, an introduction to the LTCC technology and the mechanism of LC resonance wireless interrogation are overviewed. Then, we summarise the latest developments in wirelessgas, pressure, proximity and microfluidic sensors based on LTCC technology. [ABSTRACT FROM AUTHOR]

Ceramic/resin composite is an important thermal management material for electronic packaging. The formation of a thermally conductive network of ceramic fillers in the composite is the key to improving thermal conduction performance. We design a method of ice-templated self-assembly followed by hot pressing to prepare oriented boron nitride/polyvinyl alcohol (BN/PVA) composites. First, the BN/PVA aerogel is made by freezing and then freeze-drying. BN flakes are squeezed by ice crystals to form a 3D network at the ice interfaces. After further removing the gaps between the BN flakes by hot pressing, a dense BN/PVA composite material is obtained. The resulting polymer composite has a thermal conductivity up to 10.04 W m−1 K−1 at h-BN content of 68 wt%. Theoretical analysis shows a low interfacial thermal resistance between BN flakes. This approach can potentially be used in advanced electronic packaging technology, especially in the design of thermal interface materials. [ABSTRACT FROM AUTHOR]

Lithium-ion capacitor technology (LiC) is well known for its higher power density compared to electric double-layer capacitors (EDLCs) and higher energy density compared to lithium-ion batteries (LiBs). However, the LiC technology is affected by a high heat generation problem in high-power applications when it is continuously being charged/discharged with high current rates. Such a problem is associated with safety and reliability issues that affect the lifetime of the cell. Therefore, for high-power applications, a robust thermal management system (TMS) is essential to control the temperature evolution of LiCs to ensure safe operation. In this regard, developing accurate electrical and thermal models is vital to design a proper TMS. This work presents a detailed 1D/3D electro-thermal model at module level employing MATLAB/SIMULINK® coupled to the COMSOL Multiphysics® software package. The effect of the inlet coolant flow rate, inlet coolant temperature, inlet and outlet positions, and the number of arcs are examined under the cycling profile of a continuous 150 A current rate without a rest period for 1400 s. The results prove that the optimal scenario for the LCTMS would be the inlet coolant flow rate of 500 mL/min, the inlet temperature of 30 ℃, three inlets, three outlets, and three arcs in the coolant path. This scenario decreases the module's maximum temperature (Tmax) and temperature difference by 11.5% and 79.1%, respectively. Moreover, the electro-thermal model shows -5% and -4% errors for the electrical and thermal models, respectively. [ABSTRACT FROM AUTHOR]