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Active thermal management strategies are critical for optimizing fuel cell performance by regulating stack temperature in response to output power variations. However, existing approaches often fail to adequately consider the impact of multi-source perturbations, such as gas supply perturbations or voltage distribution heterogeneity. To bridge this gap, we propose a nonlinear autoregressive exogenous network surrogate model to simulate fuel cell voltage distribution. This model is integrated into an advanced online thermal management control system. The proposed strategy employs an artificial bee colony optimization algorithm and a tube-based robust model predictive control strategy with relaxation factors. It enables real-time regulation of coolant outlet and inlet temperatures in response to variations in load current, reactant gas flow rate and pressure, and voltage distribution characteristics. Experimental results demonstrate that at a current density of 1.0 A/cm2, the strategy increased the average cell voltage by 6.1 mV, reduced the voltage extreme difference by 40.3%, and lowered the voltage standard deviation by 54.9%. The active thermal management strategy significantly enhances the performance of fuel cells under multi-source perturbations. [Display omitted] • Both thermal management system internal and external perturbations are considered. • Voltage with stack temperature and stack temperature difference is modeled. • A constraint relaxation tube-RMPC is designed for fuel cell steady-state processes. • A NARX neural network is constructed to predict fuel cell performance in real time. • The strategy improves both stack performance and voltage consistency. [ABSTRACT FROM AUTHOR]

Phase Change Material-based Battery Thermal Management System (PCM-based BTMS) has become a current research hotspot due to its high efficiency, thermal stability, and compactness. Regrettably, most existing research on PCM-based BTMS neglects the existence of mechanical vibrations, despite the inevitable involvement of such vibrations in the operating conditions of BTMS in electric vehicles. Therefore, in this study, a PCM-based BTMS is applied to a 6-cell lithium-ion battery (LIB) module, and then numerical simulation is employed to comprehensively evaluate the BTMS's performance in the existence of mechanical vibration. The findings indicate that, under mechanical vibration condition, mechanical vibration's influence on the performance of the BTMS is negligible at lower discharge rates, but becomes significant when the discharge rate surpasses a certain threshold, particularly at extremely fast discharge level, resulting in a decrease of 2.28 K in the LIB module's maximum temperature and a more uniform temperature distribution upon completion of an 8 C discharge in contrast to its stationary equivalent. Furthermore, mechanical vibration only effectively enhances the BTMS's thermal absorption capability when the PCM thickness surpasses a certain value, and this vibration also improves the capability of the BTMS to achieve uniform temperature distribution in the LIB module, especially for larger PCM thicknesses. Lastly, the BTMS's performance is able to strengthened by raising vibrational amplitude, but the impact is negligible when the amplitude is equal to or greater than 50 mm, and the thermal absorption capability of the BTMS can be augmented by raising the vibrational frequency, but there exists an enhancement limit. This work promotes the use of PCM-based BTMS in real-world applications and contributes to the advancement of LIB towards higher discharge rates. [ABSTRACT FROM AUTHOR]

AbstractThis study describes the application of cathode scrap obtained from spent lithium-ion batteries (LIBs) in the adsorptive removal of aqueous MB dye molecules. The physicochemical properties of the cathode scrap are thoroughly examined. High-resolution microscopic images display aggregation of small-sized particles in cathode scrap. Thermogravimetric analysis confirms the presence of stable metallic compounds (89% by weight) in cathode scrap above 600 °C. Surface charge analysis proves that negative surface charge of cathode scrap increases with the rising pH of the solution. The high negative surface charge facilitates adsorption of positively charged MB molecules onto negatively charged cathode scrap. The maximum quantity of MB adsorbed, as determined by the Langmuir model, is 80.42 mg/g at pH 12. Further, the material may be regenerated efficiently post-adsorption study without requiring any expensive solvent. Reusability studies demonstrate that the material maintains its activity even after five test cycles. The slight reduction in activity observed after each cycle may be attributed to the loss of some active sites into the solution during repeated use. The data clearly confirm that cathode scrap has the potential to remove various pollutants from wastewater with proper optimization of the pretreatment conditions. [ABSTRACT FROM AUTHOR]

An experimental investigation is conducted to identify the optimal blend of fluoroethylene carbonate (FEC), 3,3,3-trifluoropropylene carbonate (TFEC), and various fluorinated ethers, including 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether (HFE), 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (TTE), and bis(2,2,2-trifluoroethyl) ether (BTE), to enhance the performances of lithium-ion cells at high voltage. The cell incorporating TTE exhibits a significantly superior capacity for retention after long-term cycling at 4.5 V, which might be attributed to the improved kinetics of lithium ions and the generation of a thin, reliable, and inorganic-rich electrode–electrolyte interface. This enhancement facilitates greater lithium ion mobility within the cell, while effectively suppressing active lithium loss and side reactions between the electrodes and electrolytes at elevated voltages. Furthermore, the cell with TTE demonstrates a superior rate capability and high-temperature performance. As a result of the inherent safety characteristics of these all-fluorinated electrolytes, cells using these formulations show excellent safety properties under typical abuse scenarios. Except at elevated temperatures, none of the cells undergo thermal runaway when subjected to mechanical or electrical abuse, and there are minimal differences in safety performance across the different formulations. Considering electrochemical performance, safety, and cost factors, it can be concluded that TTE might be more optimal to cooperate with FEC and TFEC for high-performance high-voltage cells. [ABSTRACT FROM AUTHOR]

This study explores thermal management strategies for Battery Thermal Management Systems (BTMS) in electric vehicles, with a main emphasis on enhancing performance, ensuring dependability, and fostering sustainability. This book attempts to provide a full understanding of the intricate mechanisms involved in maintaining appropriate operating temperatures for battery packs by exploring various cooling solutions such as air cooling, liquid cooling, and Phase Change Materials (PCM). This study presents new findings on the combined use of various cooling methods, developments in Thermoelectric Coolers (TECs) to improve efficiency, and the crucial importance of safety standards in BTMS design. This work aims to advance innovative approaches that enhance battery performance and longevity, while also contributing to the development of more efficient and sustainable electric vehicle technology. It achieves this by addressing economic considerations and outlining future research directions. Moreover, the research emphasizes the importance of filling up the gaps in knowledge by incorporating state-of-the-art developments in BTMS. This underscores the necessity for ongoing innovation in order to address the changing requirements of electric car technology. This research adopts a comprehensive strategy by integrating several cooling strategies and emphasizing economic viability and environmental sustainability. This work aims to provide a valuable resource for researchers, engineers, and industry professionals who want to improve the efficiency, reliability, and longevity of BTMS in electric vehicles. It does this by explaining the complexities of thermal management in electric vehicles and suggesting strategies for improvement. • BTMS innovations enhance EV battery safety, efficiency, and operational lifespan. • Liquid cooling proves efficient in EVs, though complex and resource intensive. • PCM-based BTMS offers effective passive cooling with temperature control limitations. • Hybrid BTMS combining active/passive methods achieves superior performance. • AI integration in BTMS enables predictive control, optimizing thermal efficiency. [ABSTRACT FROM AUTHOR]

Photothermal therapy (PTT), as a non-invasive and selective treatment strategy, has garnered extensive research interest. Photothermal agents (PTAs) are critical components of PTT, whose light-absorbing and thermosensitive properties enable effective conversion of light energy into heat, creating localized high-temperature regions. However, PTAs often face challenges with degradation in vivo, and standalone PTT is insufficient for complete tumor cell ablation. In this study, we successfully developed a biodegradable nanoplatform for synergistic photothermal-photodynamic therapy. This platform is based on degradable antimonene nanosheets, further functionalized with a chitosan coating, and loaded with the photosensitizer Ce6. In vitro experiments demonstrated that this nanoplatform exhibits excellent biocompatibility and biodegradability. Upon laser excitation, the platform induces localized thermal effects for cell ablation and promotes reactive oxygen species generation, leading to superior anti-tumor efficacy compared to monotherapies. These findings suggest that this multifunctional nanoplatform can significantly enhance the therapeutic efficiency of synergistic phototherapy, presenting a promising candidate for cancer treatment. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries have been increasingly demonstrated in reuse applications for environmental and economic reasons, and stationary energy storage systems (ESS) and mobile ESS are emerging as reuse applications for electric vehicle batteries. Most mobile ESS deployments are at large scales, necessitating experimental data on thermal runaway (TR) to ensure comprehensive safety. In this study, TR induction and suppression experiments were conducted using fully charged NCM-based batteries at the cell (750 Wh), module (7.5 kWh), and pack (74 kWh) levels. The stepwise TR experiments measured changes in temperature, voltage, heat release rate, volatile organic compound concentrations, and vent gas composition. The suppression experiments assessed the effective water injection rate, timing, and volume required to mitigate TR propagation. The results demonstrate that in the case of TR caused by thermal abuse, early detection of battery abnormalities is possible through monitoring pre-TR indicators, such as temperature and vent gas concentration. It was also confirmed that CO2 injections can effectively cool the battery without causing damage. Furthermore, it is proposed that rapid water injection, directly contacting the battery immediately after the onset of TR, can successfully prevent TR propagation. [ABSTRACT FROM AUTHOR]

PEMFCs' operation entails the presence of heterogeneities in the generation of current, heat and water along the active surface area. Indeed, PEMFCs are open systems, and as such, operating heterogeneities are inherent to their operation. A review of the literature reveals numerous attempts to achieve uniform current density distribution. These attempts are primarily focused on bipolar plate design and operating conditions, with the underlying assumption that uniform current density correlates with enhanced performance. Most studies focus on the influence of gas flow-field design and inlet hydrogen and air flow conditioning, and less attention has been paid to the coolant operating condition. However, uncontrolled temperature distribution over a large cell active surface area can lead to performance loss and localized degradations. On this latter point, we notice that studies to date have been confined to a narrow range of operating conditions. It appears that complementary durability studies are needed in order to obtain in-depth analyses of the coupled influence of temperature distribution and gas humidification in large PEMFCs. [ABSTRACT FROM AUTHOR]

In this work, a hybrid battery thermal management system using active cooling and Phase Change Material (PCM) has been studied. The additional weight of PCM poses design challenges, and hence its optimization is required. In this regard, a PCM enclosure of a cylindrical structure with six cylindrical cells is considered in 6-row and 1-column arrangement in the present work. The thermal performance of the proposed system is numerically investigated with different thicknesses of PCM layers at constant heat generation and coolant (air) flow rates. It is found that the battery thermal management with only PCM shows unsatisfactory performance under extended severe operating conditions. However, the addition low-flow convectional cooling improved the performance and the system's reliability. It is found that for the proposed system, PCM thickness of 1 mm for the first battery cell and 2 mm for the subsequent battery cells help in better heat dissipation showing minimal thermal non–uniformity (1.1 °C) and reduced maximum temperature (39.6 °C) within the battery pack. Consequently, the optimized system shows 68.3% reduction in PCM mass as compared to the case of uniform thickness of the PCM. [ABSTRACT FROM AUTHOR]

The commercialization of perovskite solar cells (PSCs), as an emerging industry, still faces competition from other renewable energy technologies in the market. It is essential to ensure that PSCs are durable and stable in high‐temperature environments in order to meet the varied market demands of hot regions or seasons. The influence of high temperatures on the PSCs is complex, encompassing factors such as lattice strain, crystal phase changes, the creation of defects, and ion movement. Furthermore, it intensifies lattice vibrations and phonon scattering, which in turn impacts the migration rate of charge carriers. This review focuses on the durability of organic–inorganic hybrid PSCs under high temperatures. It begins by analyzing the impact of external temperature variations on the internal energy dynamics of PSCs. Subsequently, it outlines the various mechanisms provided by different functional molecules, applied to interface stabilization, grain boundary passivation, crystal growth control, electrode protection, and the development of new hole transport layers, to enhance the thermal stability of PSCs. Additionally, machine learning (ML) is discussed for predicting crystal structure stability, PSCs operational stability, and material screening, with a focus on the potential of deep learning and explainable artifical intelligence (AI) techniques in the commercialization of PSCs. [ABSTRACT FROM AUTHOR]

Thermal management of lithium‐ion batteries has received a lot of interest in the automobile sector. In commercial electric motor vehicles, an efficient battery cooling arrangement, particularly active cooling approaches, has been chosen as an ideal option. When building battery cooling systems, the physical structure and arrangement of the battery pack (BP) are vital. The current study presents a revolutionary design of a BP that incorporates cylindrical cells in a square duct and an air‐cooling (AC) medium circulated in its surroundings with the help of variable vents for inlet and outlet. A forced‐AC system is used to test lithium‐ion battery cells grouped in a 5 × 5 configured battery module. To investigate the impact of heat generation on battery thermal performance, a complete thermal analysis was performed at different discharge rates of 0.5, 1, 2, 3, and 4 C. As compared with both inlet vents at an equidistance configuration with an inlet velocity of 12 m/s and a flow rate of 1.210(−2) kg/s, the results show that the proposed design minimizes heat accumulation by enhancing the heat transfer. As a result, the peak temperature and temperature disparity decreased by 6.76% and 85.32%, respectively. A flow‐dispersing disc of 30 mm in size enhances temperature uniformity in comparison to the other intake vent design, hence improving battery safety and longevity. [ABSTRACT FROM AUTHOR]

• The refrigerator works in an off-grid configuration, and its indirect emissions are null. • Laboratory tests showed complete autonomy for several set-point temperatures for 24 h. • Implementing phase change Materials, outdoor tests showed autonomy for more days. • The use of PCMs can significantly reduce battery size and weight, improving the system's compactness. • The system is particularly suitable for areas with electrification deficiencies. The availability of vaccines, medicines, and perishable goods in remote or off-grid areas remains a formidable challenge. Integrating solar photovoltaic (PV) systems with refrigeration technology has emerged as a promising solution to address this critical need. This paper presents an autonomous solar-powered refrigerator prototype for off-grid refrigeration in remote areas utilising renewable energy. The system comprises a 160 W photovoltaic module, a 12/24 V DC compressor refrigerator, a lead-acid battery, and a Maximum Power Point Tracking (MPPT) controller. Its main feature is complete autonomy from the electricity grid, thanks to its standalone configuration. An experimental campaign evaluated the system's behaviour in the laboratory for 24 h at different set-point temperatures. A water-based Phase Change Material (PCM) was implemented to improve its autonomy in severe outdoor conditions. A further experimental campaign emulated the functioning of the prototype while managing the temperature of a sample solution whose melting temperature was equal to – 21 °C to ensure its liquid state during the tests. The target range for preserving the sample was defined at ± 1 °C. Several real conditions have been considered, such as higher cooling loads realised through 21 litres of additional thermal mass in the refrigerator and pick and place conditions for simulating the opening and closing of the door. The results demonstrate that the solar refrigerator prototype achieves complete autonomy from the electricity grid, paving the way for solutions for preserving perishable goods such as medicines and food in unelectrified areas. [ABSTRACT FROM AUTHOR]

Currently, there is considerable emphasis on the electric pump-fed cycle for liquid engine, primarily due to its design simplicity. However, its development is hindered by the underdeveloped state of power battery technology. Drawing inspiration from hybrid power technology used in electric vehicles and turbochargers, a hybrid pump feed system for throttleable engines is originally proposed as a promising solution. This system integrates the electric motor into the gas generator cycle, with several topologies evaluated. The parallel configuration featuring a mid-motor is selected for its compact structure, efficient power-splitting and energy recovery. Additionally, customized energy management strategies and optimization models are developed to effectively allocate power throughout the operational processes of liquid engines. A comparative analysis of four engine cycles is conducted under the typically variable-thrust mission. The results indicate that attributed to the conservation of turbo-gas and battery energy, the optimized hybrid pump achieves a reduction of 2.39 % compared to the turbopump and 7.15 % to the electric pump in total mass. Adaptability assessment further indicates that the mass advantage of the hybrid pump system is more significant during prolonged engine burning and deep throttling. Specific working conditions are found in which the system prefers electric-motor driving or regenerating turbine energy. Although energy-recovery results in the system efficiency decrease, it serves to lower energy demand of battery pack, thus easing the burden on cell thermal management and structural design. This study provides a practical design framework for hybrid pump-fed rocket engines in future variable-thrust missions. • The practical scheme of hybrid pump feed system for liquid engine is originally proposed. • Energy management strategies with respect to throttleable engine mission profile is designed. • A comparison is conducted between the hybrid pump, electric pump, and gas generation cycle. • Long-term firing and prolonged, deep throttling of thrust conditions are effective for the hybrid pump system. [ABSTRACT FROM AUTHOR]

Pulsating heat pipes are effective heat transfer devices that can provide passive thermal management solutions for electronics and electric vehicle batteries. In this work, the thermal performance and startup characteristics of a specially designed multiplanar PHP are investigated. Hybrid CuO + Fe3O4-water (2 wt. %) nanofluid is used as the working fluid in pulsating heat pipes. The improvement in cooling performance is assessed and compared to that of water. In mobile applications of PHPs like electric vehicle battery thermal management, components are regularly exposed to the vibrations induced by vehicle systems, and hence working characteristics of PHP under vibrations need a detailed investigation. Hence, this work also explores the effect of vibrations (~ 30 Hz) on the thermal performance of pulsating heat pipe to study its feasibility for electric vehicle battery thermal management application. The findings of this work show that with nanofluids, the startup temperature of pulsating heat pipe reduces marginally, and thermal resistance decreases by a maximum of 13.49%. Results also show that under vibrations, pulsating heat pipe shows significantly low startup temperature and reduced thermal resistance. A maximum decrease in thermal resistance under vibrations is observed at 45° pulsating heat pipe inclination; it is 11.40% for water and 8.05% for nanofluid. Also, a regression analysis is conducted to formulate a correlation to predict the thermal resistance of pulsating heat pipes based on different input parameters. The mean absolute percentage deviation (MAPD) between the predicted and experimental data is observed as 4.67% for the correlation based on current study data. [ABSTRACT FROM AUTHOR]

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Design optimization through the integration of multiple functions into a single part is a highly effective strategy to reduce costs, simplify assembly, improve performance, and reduce weight. Additive manufacturing facilitates the production of complex structures by allowing parts consolidation, resulting in optimized designs, where multiple functions are integrated into a single component. This study presents a design for additive manufacturing method for integrating multiple lattice structures to achieve thermal management and shock absorption functions. The method follows modeling and simulation phases for dimensioning and optimizing solutions to deliver the design functions at different macro- and mesoscale levels. Hierarchical complexity was leveraged to design the two-levels structure in a single part, each delivering a specific function. Specifically, the external layer addresses energy absorption and thermal insulation, while the internal layer acts as a thermal battery by incorporating a phase change material. The design of a container carried by an unmanned aerial vehicle for the transport of healthcare and biological materials is presented. The container is shock-resistant and can maintain the content at 4 ± 2 °C for at least 1 h. As it operates passively without the need for additional energy-consuming devices, it is easy to operate and contributes to increased flight autonomy. A flight mission experiment for urgent transport of blood bags confirmed the capability of the container to preserve blood integrity. This case study demonstrates that the two-layer lattice structure design represents a highly efficient approach to multifunctional design optimization. [ABSTRACT FROM AUTHOR]

Reducing the temperature of a solar cell increases its efficiency and lifetime. This can be achieved by radiative cooling, a passive and simple method relying on materials that dump heat into outer space by thermal emission within the atmosphere transparency window between 8 and 13μm. As most radiative coolers are expensive or possibly UV unstable, we have recently proposed cement‐based solutions as a robust and cost‐effective alternative. However, the assessment model used describes the cell in the radiative limit and with perfect thermal coupling to the cooler, in line with the literature. In this work, we lift these two approximations, by incorporating Auger and Shockley–Read–Hall nonradiative recombination and a finite heat transfer coefficient at the cell/cooler interface, to obtain a thermal description of the cell/cooler stack closer to reality, while preserving the universality and transparency of the detailed‐balance approach. We use this model to demonstrate that the cell performance gains provided by a radiative cooler are underestimated in the radiative limit and are hence more prominent in devices with stronger nonradiative recombination. Furthermore, we quantify the relation between cell temperature and heat transfer coefficient at the cell/cooler interface and show how this can be used to define design requirements. The extended model developed, and the resulting observations provide important guidelines toward the practical realization of novel radiative coolers for solar cells, including cement‐based ones. [ABSTRACT FROM AUTHOR]

Batteries are widely used in energy storage systems (ESS), and thermal runaway in different types of batteries presents varying safety risks. Therefore, comparative research on the thermal runaway behaviors of various batteries is essential. This study investigates the thermal runaway characteristics of sodium-ion batteries (NIBs), lithium iron phosphate batteries (LFP), and lithium-ion batteries with NCM523 and NCM622 cathodes. The experiments were conducted in a nitrogen-filled constant-volume sealed chamber. The results show that the critical surface temperatures at the time of thermal runaway are as follows: LFP (346 °C) > NIBs (292 °C) > NCM523 (290 °C) > NCM622 (281 °C), with LFP batteries exhibiting the highest thermal runaway critical temperature. NIBs have the lowest thermal runaway triggering energy (158 kJ), while LFP has the highest (592.8 kJ). During the thermal runaway of all four battery types, the primary gases produced include carbon dioxide, hydrogen, carbon monoxide, methane, ethylene, propylene, and ethane. For NCM622 and NCM523, carbon monoxide is the dominant combustible gas, with volume fractions of 35% and 29%, respectively. In contrast, hydrogen is the main flammable gas for LFP and NIBs, with volume fractions of 44% and 30%, respectively. Among these, NIBs have the lowest lower flammability limit (LFL), indicating the highest explosion risk. The thermal runaway characteristics of 50 Ah batteries provide valuable insights for battery selection and design in energy storage applications. [ABSTRACT FROM AUTHOR]

Our study aims to assess the thermal inactivation of non-proteolytic type B Clostridium botulinum spores in a plant-based fish and to evaluate the potential of alternative heat treatments at temperatures below the safe harbor guidelines established for vacuum-packed chilled products of extended durability. First, the heat resistance of the spore suspension was determined using capillary tubes in potassium phosphate buffer at 80°C. The D80 value was estimated to be 0.7–0.8 min. Then, inactivation was studied in a plant-based fish alternative using "thermal cells equipment." Inactivation kinetics were obtained at four temperatures: 78, 81, 84 and 85°C, in duplicates. A secondary model describing log10D values versus temperatures was fitted to the dataset. The model parameters ZT and log10Dref (log10D at Tref 82°C) were estimated to be 8.02 ± 0.46°C and 0.32 ± 0.02, respectively. Model validation was done first with additional data collected at three different temperatures (79.1, 82.5, 87.5°C) and second with literature data. The time required to deliver 6 log reduction in the plant-based food matrix was predicted at temperatures within the range 80–90°C. The recommended processing for vacuum-packed chilled products, 90°C for 10 min, was evaluated. We demonstrated that the recommended processing is approximately five times more than the time required for 6 log reduction of non-proteolytic C. botulinum in the plant-based fish alternative, indicating a substantial margin of safety. Our findings highlight the importance of conducting product-specific studies for the evaluation of thermal processing and the potential of process optimization for certain product categories. [ABSTRACT FROM AUTHOR]

AbstractThe nozzle geometry effect on flow and heat transfer behaviors for swirling impinging micro-slot jets has been numerically explored to enhance the thermal performance of batteries intended for future electric vehicles. In this study, the total spiraling length was limited to 290 mm due to the constraints imposed by the slot nozzle thickness of 1 mm and two complete revolutions of the generated helix. Nozzle geometries and jet-to-target distances varied from 3 to 9 and 1 to 4. The turbulent kinetic energy-epsilon model was used for the numerical simulation work under the Reynolds number, which ranged from 5000 to 20000. The results showed that the heat transfer characteristic depended on the nozzle geometry flow structure. The heat transfer rate at a jet-to-target distance of 1 was better than at a jet-to-target distance of 4. Furthermore, the average heat transfer in case of the nozzle geometry of 3 at a jet-to-target distance of 1 was the highest value, increasing by about 17.5%. However, above 31.5% of the average heat transfer value in case of the nozzle geometry of 7 and 9 at a jet-to-target distance of 4 became better. [ABSTRACT FROM AUTHOR]

Here, we have synthesized Fe-doped Cu2NiSnS4 (CNTS) thin film solar cells by thermal evaporation method. Our aim is to create a homojunction solar cell by manipulating the conductivity type of CNTS thin film by dopant Fe. The synthesized CNTS and Fe-doped CNTS were subjected to structural, optical, morphological, and electrical studies. From the XRD analysis, it is seen that the synthesized thin film possesses a cubic structure, and Raman analysis revealed the presence of the CNTS phase. From UV analysis, we found that the incorporation of the dopant Fe into CNTS thin film induced sp-d interaction that resulted in a decrease in bandgap from 1.80 to 1.39 eV and also leading to a change in conductivity type from N-type to P-type due to a shift in the fermi level which is revealed by Mott Schottky plot. Moreover, the doped CNTS thin film shows comparatively lesser Urbach energy, which indicates that the doped CNTS thin film is less prone to band tailing. From the TEM-SEAD pattern, the hkl parameters were found, which are identical to the XRD analysis. The elemental states of the quaternary compound were found using XPS. The fabricated Fe-doped CNTS solar cells resulted in increased charge carrier concentration from 1.53 × 1016 to 9.02 × 1016 m−3. The short circuit current increased from 8.5 mAcm−2 to 14.0 mAcm−2, and the photoconversion efficiency increased from 2.6 to 4.8%. [ABSTRACT FROM AUTHOR]

Cs2PtI6 is a promising photoabsorber with a direct bandgap of 1.4 eV and a high carrier lifetime; however, the cost of Pt inhibits its commercial viability. Here, we performed a cost analysis and experimentally explored the effect of replacing Pt with earth-abundant Ni in solution-processed Cs(PtxNi1−x)(I,Cl)3 thin films on the properties and stability of the perovskite material. Films fabricated with CsI and PtI2 precursors result in a perovskite phase with a bandgap of 2.13 eV which transitions into stable Cs2PtI6 with a bandgap of 1.6 eV upon annealing. The complete substitution of PtI2 in films with CsI + NiCl2 precursors results in a wider bandgap of 2.35 eV and SEM shows two phases—a rod-like structure identified as CsNi(I,Cl)3 and residual white particles of CsI, also confirmed by XRD and Raman spectra. Upon extended thermal annealing, the bandgap reduces to 1.65 eV and transforms to CsNiCl3 with a peak shift to higher 2-theta. The partial substitution of PtI2 with NiCl2 in mixed 50-50 Pt-Ni-based films produces a bandgap of 1.9 eV, exhibiting a phase of Cs(Pt,Ni)(I,Cl)3 composition. A similar bandgap of 1.85 eV and the same diffraction pattern with improved crystallinity is observed after 100 h of annealing, confirming the formation of a stable mixed Pt-Ni phase. [ABSTRACT FROM AUTHOR]

This study delves into the computational exploration of the impact of magnetic intensity, magnetic nanofluid, flow rates and heat transfer coefficient in the form of Nusselt number on inclined ribbed channels with both parallel and staggered configurations for the cooling of sodium-ion and lithium-ion batteries in electric vehicles. Employing Fe3O4 + H2O as the working fluid, within a minichannel with multiple magnets at different locations, namely 15 mm, 25 mm and 15 mm and 25 mm, the parallel and staggered inclined ribbed channel Nusselt number (Nu) increased with magnetic field intensity, reaching maximum of 152.81% for staggered ribbed minichannel configuration at 2000 Gauss (G). Similarly, the skin friction experienced an increment with magnetic field intensity for staggered ribbed minichannel configuration and for parallel ribbed minichannel when both the magnets were placed at the location of 15 mm and 25 mm from the inlet but decreased with increasing Reynolds number. Notably, the thermal enhancement factor (TEF) consistently surpassed greater than unity for all investigated cases. These findings carry significant implications, particularly in EV cooling, offering valuable insights for developing more efficient and tailored cooling solutions for advanced EV battery thermal management. [ABSTRACT FROM AUTHOR]

This study firstly experimentally determined the performance of direct ammonia solid oxide fuel cell (DA-SOFC) under various O 2 -enriched cathode gas conditions at 750 °C and 700 °C. Results indicate a significant 40.4% decrease in DA-SOFC power density when temperature dropped from 750 °C to 700 °C, more pronounced than in H 2 –SOFCs. O 2 -enriched operation improved DA-SOFC power density, with increases ranging from 7.9% to 22.9% as O 2 molar fraction at the cathode inlet rose from 21% to 100% at 750 °C. And at 700 °C, such promoting effect on DA-SOFC was more significant than on H 2 –SOFC. Interestingly, DA-SOFC open circuit voltage (OCV) showed a nonmonotonic trend with increasing O 2 molar fraction, peaking between 30% and 60% O 2. Subsequently, multi-physics modeling of DA-SOFC were performed. The numerical results revealed that the observed increase in power density of DA-SOFC in O 2 -enriched operation mode was primarily resulted from the reduction in concentration polarization, rather than the changed OCVs/Nernst voltages. • Explanations of the factors controlling the enhancement of O 2 -enriched DA-SOFCs. • Identified and explained the nonlinear trend of OCV with increasing O 2. • Confirmed and quantified the impact of O 2 -enriched operation on DA-SOFCs. [ABSTRACT FROM AUTHOR]

Under the extreme usage scenario, the thermal runaway gases (H 2 and CO 2) will be produced and leaked from the electrolyte of lithium battery. The molecular structure, adsorption properties, charge density difference (CDD), density of state (DOS), partial density of state (PDOS), desorption time, sensitivity, work function (WF) and frontier orbital theory are investigated to analyze the sensing characteristics toward H 2 and CO 2 of CdS monolayer, Ag–CdS, Pt–CdS, and Pd–CdS. The optimal CdS monolayer structure consist of hexagons, and the bandgap is 2.043 eV. After heterometal doping, the E g decreases to 0.339 eV for Ag–CdS, 1.202 eV for Pt–CdS, and 1.358 eV for Pd–CdS. The adsorbing energy of the CdS–H 2 , Ag–CdS–H 2 , Pt–CdS–H 2 , and Pd–CdS–H 2 is - 2.27 eV, - 0.80 eV, - 0.81 eV, and - 0.81 eV respectively, which correspond to the desorption time of 1.33 × 1026, 27.2, 40.1, and 40.1 s at 300 k in sequence. At room temperature, the response value of Pt–CdS to hydrogen is 78.61%, while the response value of Pd–CdS to hydrogen reaches as high as 98.17%. The Pt-doped and the Pd-doped CdS monolayer shows potential for room temperature H 2 sensing, while the CdS monolayer displays the potential for H 2 and CO 2 cleaning. The Sensing Properties Toward Li-ion Battery Thermal Runaway Gases (H 2 , CO 2) for Pure and Heterometal-doped (Pt, Pd, Ag) CdS Monolayer: A DFT study. [Display omitted] • The optimal structure of heterometal-doped CdS were discussed. • The adsorption properties of heterometal-doped CdS toward H 2 , CO 2 , were analyzed. • The electronical properties of gas adsorption model were analyzed. • The desorption time and sensitivity under different temperatures were discussed. [ABSTRACT FROM AUTHOR]

High‐performing organic solar cells (OSCs) being processed in ambient conditions and possessing long‐term stability are desired toward commercialization. Here, resultantly bifunctional additive is proposed for organic active layer, which can greatly enhance humidity endurance during the air‐processing of the active layer and device stability in the meantime. Intriguingly, with 1% octamethyltrisiloxane (3Si) as the additive, casting PM6:L8‐BO active layer even in 90% relative humidity (RH) air could show comparable efficiency to that in N2 condition. Furthermore, the 3Si‐processed active layers also display remarkably enhanced thermal and light stabilities in conventional OSCs. After thermal aging at 85 °C for 1000 h and simulated solar light aging with UV band at 100 mW cm−2 and 55°C for 1000 h, the 3Si‐processed PM6:L8‐BO binary OSCs maintain 91.6% and 86.1% of the initial efficiency, leading to final averaged efficiencies of 16.17% and 15.42%, respectively. The results represent the most stable OSCs based on additive strategy. The universality of siloxane as a humidity‐resistant and stabilizing agent is also confirmed with other active layer systems, paving a way for broader application of the bifunctional additive. [ABSTRACT FROM AUTHOR]

An efficient battery pack-level thermal management system was crucial to ensuring the safe driving of electric vehicles. To address the challenges posed by insufficient heat dissipation in traditional liquid cooled plate battery packs and the associated high system energy consumption. This study proposes three distinct channel liquid cooling systems for square battery modules, and compares and analyzes their heat dissipation performance to ensure battery safety during high-rate discharge. The results demonstrated that the extruded multi-channel liquid cooled plate exhibits the highest heat dissipation efficiency. Subsequently, response surface experiments were conducted to analyze the width parameters of various flow channels in the liquid cooled plate Finally, the Design of Experiment (DOE) was employed to conduct optimal Latin hypercube sampling on the flow channel depth (H), mass flow (Q), and inlet and outlet diameter (d), combined with a genetic algorithm for multi-objective analysis. The Tmax of the battery module decreased by 6.84% from 40.94°C to 38.14°C and temperature mean square deviation decreased (TSD) by 62.13% from 1.69 to 0.64. Importantly, the battery thermal management model developed in this study successfully met heat dissipation requirements without significantly increasing pump energy consumption. [ABSTRACT FROM AUTHOR]

Objective To analyze the explosion hazard of gases produced after the thermal runaway of lithium batteries and to explore the relationship between the lower explosive limit of gases and influencing factors, thereby establishing a research foundation for improving the safety management of lithium battery electrochemical energy storage technology. Methods By analyzing the influencing factors of the lower explosive limit of gases after lithium battery thermal runaway, an experimental study was conducted on the two key factors of hydrogen concentration and temperature in the gases produced after thermal runaway. The correlation between the lower explosive limit and influencing factors was analyzed. Results When the hydrogen concentration in the gases produced after lithium battery thermal runaway ranged from approximately 40% to 75%, the lower explosive limit gradually decreased from 6.6% to 4.8% as the hydrogen concentration increased. The linear relationship between hydrogen concentration and the lower explosive limit was characterized by the equation y = -0.051 x + 8.612, with a correlation coefficient of 0.998. For gas samples with a hydrogen concentration of about 50%, the lower explosive limit gradually decreased from 6.0% to 3.6% as the temperature rose from 30 ℃ to 250 ℃. The characteristic curve was y = -0.000 06 x2 + 0.008 x + 5.805, with a correlation coefficient of 0.969. Conclusions As the hydrogen concentration increased or the temperature rose, the lower explosive limit of gases produced after lithium battery thermal runaway showed a decreasing trend, displaying a good linear relationship. The lower explosive limit could be predicted through hydrogen concentration and temperature data. [ABSTRACT FROM AUTHOR]

In inverter technology for hybrid and electric vehicles, some properties, such as low weight, compactness, small size, high power density, and high efficiency, are highly required because they affect vehicle production costs and fuel economy. Bringing reliable and cheap devices with high response rates into being, which is in close relation with circuit design, miniaturization, and appropriate selection of components, have become one of the main topics of scientific research in electronics. One of the main obstacles to achieving these goals is the bulkiness of inductors and capacitors. These essential building blocks of the converter topology are used to reduce input current and output voltage ripples, which are closely related to thermal stress in batteries, affecting their lifespan. This study proposes a GaN-based multidevice interleaved boost converter (MDIBC) topology for hybrid vehicles. The topology is investigated in terms of power loss, efficiency, current and voltage ripples, and size of passive components under two salient case studies at various switching frequencies. In both cases, current and voltage are reduced by smaller values of passive components without sacrificing efficiency. Efficiencies ranging between 97.34 and 97.83%, are achieved with passive components remaining in the benchmark converter. [ABSTRACT FROM AUTHOR]

The thermal conductivity of heterogeneous materials used in thermal batteries is difficult to measure. These materials must be handled under controlled atmosphere with methods adapted to their porous nature. The method presented in this work uses heating plates to send a sinusoidal thermal signal to the tested sample. The whole setup is confined in a glovebox to ensure the composition and hygrometry of the atmosphere. Parametric computer simulations with varying thermal conductivity (λ) of the sample and thermal resistance (h) of the contacts as inputs were performed to calculate the phase shifts associated with two thicknesses of the sample. Experimental measurements of phase shifts on these two configurations allowed the identification of the only couple (λ, h) which matches the phase shifts on the respective thicknesses. This method is validated using the reference material BK7 at different temperatures. Thermal conductivities of different materials used in thermal batteries are also given using this method. Nomenclature. [ABSTRACT FROM AUTHOR]

Lithium‐ion batteries (LiBs) are the leading choice for powering electric vehicles due to their advantageous characteristics, including low self‐discharge rates and high energy and power density. However, the degradation in the performance and sustainability of lithium‐ion battery packs over the long term in electric vehicles is affected due to the elevated temperatures induced by charge and discharge cycles. Moreover, the thermal runaway (TR) issues due to the heat generated during the electrochemical reactions are the most significant safety concern for LiBs, as inadequate heat dissipation can be potentially hazardous, leading to explosions and fires. Considering the safety of EVs and for better performance, understanding the mechanism of TR is of paramount importance. This review provides a comprehensive analysis of the TR phenomenon and underlying electrochemical principles governing heat accumulation during charge and discharge cycles. Furthermore, the article explores the cell modeling and thermal management techniques intended for both individual lithium‐ion battery cells and larger battery packs, with a particular emphasis on enhancing fire prevention and safety measures. The main goal of this review paper is to offer new insights to the developing battery community, assisting in the development of efficient battery thermal management systems (BTMS) using enhanced cooling methodologies. This article could also support the advancement of next‐generation electric vehicle battery packs equipped with built‐in safety features to improve the cycle life of LiBs and prevent thermal runaway accidents. [ABSTRACT FROM AUTHOR]

• Under steady-state conditions, to maximize COP, optimal S Eva is 0.5 K, optimal S Chi is affected by the H Bat and ambient temperature. • Under the transient condition, the EC of single-point optimization is 1490 kJ, which is 2.3 % smaller than that of the basic condition. • Under the transient condition, the EC of two-point optimization is 1460 kJ, which is 4.3 % smaller than that of the basic condition. The refrigerant superheat significantly impacts on the energy consumption of the vehicle cabin and battery collaborative thermal management system. The study investigates the problem using a genetic algorithm. Firstly, the model of collaborative thermal system is established and verified. Then, the coefficient of performance (COP) maximization is taken as the optimization target during steady-state conditions. The results show that the optimal refrigerant superheat at the evaporator outlet (S Eva) is very low for different heat dissipation of the battery (H Bat) as well as ambient temperature, while the optimal refrigerant superheat at the chiller outlet (S Chi) is affected by the H Bat as well as ambient temperature. Finally, according to conclusions under the steady state, the S Eva is set to 1 K and taking the energy consumption (EC) as the response under transient condition, the S Chi is determined. The results indicate that when the S Chi is decided by single-point optimization, the optimal S Chi is 18 K, and the EC is 1490 kJ, which is 2.3 % energy saving compared to the basic condition. When the S Chi is decided by two-point optimization, the optimal two superheats are 12 K and 37 K and the EC is 1460 kJ, which is 4.3 % energy saving compared to the basic condition. [ABSTRACT FROM AUTHOR]

While thermal convection cells exhibit left–right and top–bottom symmetries at low Rayleigh numbers ( R a ), the emergence of coherent flow structures, such as elliptical large-scale circulation in Rayleigh–Bénard convection (RBC), breaks these symmetries as the Rayleigh number increases. Recently, spatial double-reflection symmetry was proposed and verified for two-dimensional RBC at a Prandtl number of 6.5 and R a values up to 10 10 . In this study, we examined this new symmetry at a lower Prandtl number of 0.7 and across a wider range of Rayleigh numbers, from 10 7 to 10 13 . Our findings reveal that the double-reflection symmetry is preserved for the mean profiles and flow fields of velocity and temperature for R a < 10 9 , but it is broken at higher Rayleigh numbers. This asymmetry at high R a values is inferred to be induced by a flow-pattern transition at R a = 10 9 . Together with the previous study, our results demonstrate that the Prandtl number has an important influence on the symmetry preservation in RBC. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) exhibit a promising application as a heat storage medium in battery thermal management. However, the flammability, low thermal conductivity, and leakage problems of organic PCMs constrain the development. In this study, a novel strategy based on inorganic hydrated salt with natural nonflammability was proposed. Sodium acetate trihydrate and disodium hydrogen phosphate dodecahydrate composite materials (SAT-DSP) were synthesized without affecting the properties. The prepared SD@SiO2 with sodium silicate as the precursor, while SAT-DSP as the core material, possessed the dual heat storage performance of phase transition and thermochemical heat storage. The SiO2 shell with a dense surface successfully realized the encapsulation of SAT-DSP, and the combined effect of heterogeneous nucleation and mesoporous confinement effectively inhibited the phase separation of phase change materials. The optimal ratio of SD@SiO2 was determined through a comprehensive analysis of morphology, thermal stability, and thermal storage properties. The heat storage density was up to 509.18 J g−1 with a phase transition temperature of 78.78 °C. It improved the chemical instability and leakage of hydrated salts and centralized the dehydration process of SAT-DSP to achieve rapid response. Even after continuous heating on a 120 °C heating platform for 30 min, the surface temperature of SD@SiO2 was maintained within a safe range (< 65 °C). This inorganic phase change material exhibited considerable potential for application in battery thermal runaway protection. [ABSTRACT FROM AUTHOR]

This article provides a comprehensive overview of the potential challenges and solutions of second-life batteries. First, safety issues of second-life batteries are investigated, which is highly related to the thermal runaway of battery systems. The critical solutions for the thermal runaway problem are discussed, including structural optimization, parameter identification, advanced BMS, and artificial intelligence (AI)-based control strategies. Furthermore, the cell inhomogeneity problem of second-life battery systems is analyzed, where the passive balancing strategy and active balancing strategy are reviewed, respectively. Then, the compatibility issue of second-life batteries is investigated to determine whether electrical dynamic characteristics of a second-life battery can meet the performance requirements for energy storage. In addition, date security and protection methods are reviewed, including digital passport, smart meters and Internet of Things (IoT). The future trends and solutions of key challenges for second-life battery utilization are discussed. [ABSTRACT FROM AUTHOR]

Electric and hybrid vehicles have become widespread in large cities due to the desire for environmentally friendly technologies, reduction of greenhouse gas emissions and fuel, and economic advantages over gasoline and diesel vehicles. In electric vehicles, overheating, vibration, or mechanical damage due to collision with an object or another vehicle can lead to the failure of lithium-ion batteries up to thermal runaway and fire. Therefore, the development of battery safety control systems is one of the most important factors contributing to the large-scale electrification of public and private transport. This review examines the design features of the location and management of the battery pack to achieve maximum safety and operational efficiency when using an electric vehicle. The power characteristics and life-cycles of various types of lithium-ion batteries depending on the chemical nature of their electrodes are considered, using the example of commercial vehicles'—Tesla, Nissan Leaf, Porsche Taycan, Zeekr, and Chevrolet Volt—strategic technologies for the placement and packaging of batteries, and battery cooling and monitoring systems (State of Health and State of Charge) are also discussed. In conclusion, the current challenges in the field are summarized and promising research directions are proposed. [ABSTRACT FROM AUTHOR]

Solid-state batteries (SSBs) offer significant improvements in safety, energy density, and cycle life over conventional lithium-ion batteries, with promising applications in electric vehicles and grid storage due to their non-flammable electrolytes and high-capacity lithium metal anodes. However, challenges such as interfacial resistance, low ionic conductivity, and manufacturing scalability hinder their commercial viability. This study conducts a comprehensive scientometric analysis, examining 131 peer-reviewed SSB research articles from IEEE Xplore and Web of Science databases to identify key thematic areas and bibliometric patterns driving SSB advancements. Through a detailed analysis of thematic keywords and publication trends, this study uniquely identifies innovations in high-ionic-conductivity solid electrolytes and advanced cathode materials, providing actionable insights into the persistent challenges of interfacial engineering and scalable production, which are critical to SSB commercialization. The findings offer a roadmap for targeted research and strategic investments by researchers and industry stakeholders, addressing gaps in long-term stability, scalable production, and high-performance interface optimization that are currently hindering widespread SSB adoption. The study reveals key advances in electrolyte interface stability and ion transport mechanisms, identifying how solid-state electrolyte modifications and cathode coating methods improve charge cycling and reduce dendrite formation, particularly for high-energy-density applications. By mapping publication growth and clustering research themes, this study highlights high-impact areas such as cycling stability and ionic conductivity. The insights from this analysis guide researchers toward impactful areas, such as electrolyte optimization and scalable production, and provide industry leaders with strategies for accelerating SSB commercialization to extend electric vehicle range, enhance grid storage, and improve overall energy efficiency. [ABSTRACT FROM AUTHOR]

Lithium titanate oxide cells are gaining attention in electric vehicle applications due to their ability to support high-current charging and their enhanced thermal stability. However, despite these advantages, safety concerns, particularly thermal runaway, pose significant challenges during abuse conditions such as overcharging. In this study, we investigated the effectiveness of various dielectric fluids in mitigating thermal runaway during overcharge abuse tests of cylindrical LTO cells with a capacity of 10 Ah. The experimental campaign focused on overcharging fully charged cells (starting at 100% State of Charge) at a current of 40A (4C). The tests were conducted under two conditions: the first benchmark test involved a cell exposed to air, while the subsequent tests involved cells submerged in different dielectric fluids. These fluids included two perfluoropolyether fluorinated fluids (PFPEs) with boiling points of 170 °C and 270 °C, respectively, a synthetic ester, and a silicone oil. The results were analyzed to determine the fluids' ability to delay possible thermal runaway and prevent catastrophic failures. The findings demonstrate that some dielectric fluids can delay thermal runaway, with one fluid showing superior performance with respect to the others in preventing fire during thermal runaway. The top-performing fluid was further evaluated in a simulated battery pack environment, confirming its ability to mitigate thermal runaway risks. These results provide important insights for improving the safety of battery systems in electric vehicles. [ABSTRACT FROM AUTHOR]

Battery safety is a multifaceted concern, with thermal runaway standing out as a primary issue. In this work, we introduce a novel temperature‐responsive, self‐protection electrolyte governed by the phase separation dynamics of poly (butyl methacrylate) (PBMA) in lithium salt/tetraglyme (G4) blends. This innovation effectively mitigates the risks associated with thermal runaway in lithium batteries. Our electrolyte exhibits a temperature‐responsive‐recovery characteristic, imparting intelligent capabilities to lithium batteries. At temperatures of >105 °C, the electrolyte transitions from a homogeneous phase to a segregated state, comprising a PBMA‐rich phase with low conductivity and a high conductivity phase containing dissolved lithium salt in G4. The deposition of the PBMA‐rich phase on the electrode surface obstructs the ion transport, thereby averting a thermal runaway. Subsequently, upon returning to room temperature of 25 °C, the electrolyte reverts to its homogeneous, highly conductive state, with battery capacity resuming at approximately 94 %. Thus, our electrolyte offers a robust, reversible, smart self‐protection for batteries. Additionally, it demonstrates exceptional cycling performance at room temperature. Our findings open new avenues for thermo‐reversible and self‐protective electrolytes, advancing the safe and widespread adoption of lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Overcharging is a primary cause of thermal runaway in ternary lithium‐ion batteries, often leading to serious safety incidents. Early detection of thermal runaway during overcharging is therefore critical. This study investigates a 5 Ah ternary lithium battery pack, applying appropriate preload force to simulate real‐world conditions. Various overcharge experiments are conducted under different conditions, and changes in battery voltage, temperature, and expansion force are thoroughly analyzed. The results indicate that under the same initial conditions, higher charging rates accelerate the temperature rise in the lithium battery. Additionally, the internal gas generation rate increases, causing a faster rise in edge pressure and leading to earlier battery cracking. Building on these findings, a three‐level early warning algorithm is developed, which comprehensively considers voltage, temperature, and expansion force changes. Experimental validation demonstrates that this algorithm can accurately identify the current stage of thermal runaway and detect the transition to the third warning stage 604 s before complete failure, thus providing critical protection for the safe operation of the battery pack. This study offers valuable guidance for enhancing the monitoring and early warning capabilities of battery management systems. [ABSTRACT FROM AUTHOR]

The modern world is moving towards electric vehicles (EV) due to the increment in greenhouse gas (GHG) emissions, global warming, and the lack of fossil fuels. EVs can overcome these issues by using batteries instead of fuel. But increasing and maintaining the batteries is a major challenge in EVs because of the large heat emissions from the batteries. In order to overcome these issues and increase the performance of the batteries, a heat pipe (HP) is attached to the passive cooling system. This study aims to improve the performance of batteries and the thermal conductivity of HP with a combination of refrigerant and nanofluid (nanorefrigerant) as working fluids. Copper HP with R-134a or SWCNT is selected for this study. The thermal resistance and thermal conductivity of HP with R-134a and SWCNT were observed for several heat conditions. From the study, it was well observed that changing the working fluid inside the HP affects the thermal performance and the cooling capacity of batteries. Fixing an HP to a battery would decrease the battery's temperature effectively. Furthermore, increasing the heat power in an evaporator section decreases the thermal resistance and enhances thermal conductivity with the shortest time limit because of Brownian motion. [ABSTRACT FROM AUTHOR]

Na3V2 (PO4)3 (NVP) is considered to be a promising cathode material for sodium-ion batteries (SIBs). Ion doping can effectively improve its structural deformation, poor conductivity, and electrochemical performance. However, the research on the effect of ion doping on the thermal stability of NVP is still limited. In this paper, Mg/Ti co-doped and Mn/Ti co-doped modified NVP with carbon nanotubes (CNTs) (MgTi@ CNTs and MnTi@CNTs) were prepared, respectively, and X-ray diffraction (XRD) results proved that MgTi@CNTs and MnTi@CNTs have good structural stability and crystallinity. The electrochemical performance indicates that the dual strategy of p-n-type co-doping and CNT coating provides superior sodium storage performance, enhancing both electronic conductivity and ion diffusion. Secondly, based on the safety point of view, the thermal stability of p-n-type ion-doped NVP and its mixed system with electrolyte in a charged state was studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and accelerated calorimeter (ARC). The results show that the optimized MgTi@CNTs and MnTi@CNTs electrodes exhibit excellent thermal stability in the absence of electrolytes, indicating their high intrinsic safety. However, it is worth noting that in the electrode/electrolyte system, p-n-type ion-doped NVP have higher reactivity with the electrolyte, and their comprehensive thermal safety is lower than that of NVP. Therefore, in practical applications, it is necessary to comprehensively consider the thermal stability of the material and the thermal safety of its mixed system with the electrolyte. This paper provides a data basis for the practical application of NVP in SIBs. [ABSTRACT FROM AUTHOR]

Copyright of Advances in New & Renewable Energy is the property of Editorial Office of Advances in New & Renewable Energy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

High-frequency ripple current excitation reduces the lithium precipitation risk of batteries during self-heating at low temperatures. To study the heat generation behavior of batteries under high-frequency ripple current excitation, this paper establishes a thermal model of LIBs, and different types of LIBs with low-temperature self-heating schemes are studied based on the established thermal model. Under the consideration of contact impedance, this paper tests the heat production of the battery under high-frequency ripple current and establishes an accurate thermal model of a lithium-ion battery under the excitation of high-frequency ripple current, and the absolute value of the maximum relative error between the measurement results and the thermal model is reduced from 181.4% to less than 20.6%, which makes the battery thermal model under high-frequency ripple current excitation more accurate. Then, based on the established thermal model, the calculation method of the minimum heating power required for different batteries under the same low-temperature self-heating conditions is proposed for batteries of different sizes, thermal properties, and internal resistances, and the preferred low-temperature self-heating scheme for different types of batteries is proposed by comparing the current multiplicity required for different high-frequency ripple current self-heating schemes. [ABSTRACT FROM AUTHOR]

Stationary battery energy storage systems (BESS) have been developed for a variety of uses, facilitating the integration of renewables and the energy transition. Over the last decade, the installed base of BESSs has grown considerably, following an increasing trend in the number of BESS failure incidents. An in-depth analysis of these incidents provides valuable lessons for improving the safety of BESS. This paper discusses multiple safety layers at the cell, module, and rack levels to elucidate the mechanisms of battery thermal runaway and BESS failures. We further provide insights into different safety aspects of BESS, covering the system architecture, system consideration, safety standards, typical quality issues, failure statistics, and root causes. Various mitigation strategies are recommended and summarized. We highlight the importance of multi-disciplinary approaches in knowing, managing, and mitigating the risks associated with BESS. In general, this review paper serves as a guide for understanding the safety of BESS. [ABSTRACT FROM AUTHOR]

The extensive utilization of lithium-ion batteries in large-scale energy storage has led to increased attention to thermal safety concerns. The conventional monitoring methods of thermal runaway in batteries exhibit hysteresis and singleness, posing challenges to the accurate and quantitative assessment of the health and safety status of energy storage systems. Assessing the safety status and thermal runaway warning threshold of lithium-ion batteries typically necessitates the collection of a substantial amount of battery operation and thermal runaway test data. The simulation offers an efficacious and convenient solution for establishing the safety status database of lithium-ion batteries. A multi-physical-field coupling simulation model incorporating electrochemical, thermal, and mechanical processes is employed to simulate the changes in the characteristic parameters throughout the battery thermal runaway process under different conditions. The thermal safety state of the cell is analyzed by calculating the characteristic values including voltage, temperature, and deformation. The simulation results demonstrate that the deformation will reach its warning value in advance of other characteristics, thereby enabling the early detection of thermal runaway. In the case of electrical abuse, the voltage is more susceptible than temperature and deformation. The coupling simulation and safety state calculation method based on characteristic parameters enable the quantification of the safety state of the cell and even the module. The thermal safety threshold of lithium-ion batteries is analyzed, and the security status of the energy storage system can be predicted by deep learning, thereby facilitating the further application of artificial intelligence in the field of energy storage security. [ABSTRACT FROM AUTHOR]

It is of paramount importance to gain a comprehensive understanding of the internal and external factors contributing to thermal runaway in commercial LiFePO4 lithium-ion batteries (LIBs) in order to ensure the safe operation of the battery and to control any potential risks. In this work, we investigate the progression of internal temperature and cycle performance of commercial LiFePO4 LIBs when they are subjected to a range of extreme operational conditions, including short circuits, overcharging, punctures, and external pressure. A simulation has been employed to elucidate the mechanism of thermal runaway induced by continuous high temperatures. The findings indicate that, while harsh operating environments can elevate internal battery temperatures and reduce performance, they are not the fundamental cause of thermal runaway. Instead, it is the continuous exposure to high temperatures above a critical threshold that serve as the primary trigger. Therefore, the most effective method of preventing heat-related loss of control in batteries is to control the ambient temperature and avoid prolonged exposure to high temperature. Furthermore, it is imperative to implement comprehensive emergency protocols for high-temperature scenarios and to take proactive measures in extreme environments to prevent safety incidents resulting from battery thermal runaway. This study offers insights into exploring the root causes of thermal runaway, investigating both internal and external factors with the aim of enhancing safe and stable operation within large-scale LiFePO4 LIBs energy storage systems. It contributes towards revealing the complex multi-dimensional evolution mechanism and coupling effects within LiFePO4-based LIBs energy storage systems throughout their lifecycle. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)