Search Results (575)

State-of-charge (SOC) estimation for lithium-ion batteries in smartphones is complicated by nonlinear load variation, electro-thermal coupling, aging effects, and heterogeneous user behaviors. This study proposes a multi-physics coupled SOC estimation framework, termed the Multi-Physics Thermo-Electrochemical Coupled SOC Model (MTEC-SOC), to characterize battery behavior under representative user-load conditions within controlled ambient thermal boundaries. The model combines system-level power profiling, thermal evolution, voltage dynamics, and aging-related capacity correction within a unified framework. To support model development and validation, a dual-source dataset is established using laboratory battery characterization data and real-world smartphone behavioral data, from which users are classified into light, heavy, and mixed usage patterns. Comparative results against four benchmark models (M1–M4) show that MTEC-SOC achieves the highest overall accuracy, with average MAE, RMSE, and TTE error values of 0.0091, 0.0118, and 0.08 h, respectively. The results suggest distinct degradation tendencies across user types: calendar aging dominates under prolonged high-voltage dwell in light-use scenarios, whereas, within the tested thermal range, heavy-use scenarios exhibit stronger voltage sag, relative temperature rise, and polarization-related stress; mixed-use scenarios are characterized by transient responses induced by abrupt load switching. Sensitivity analysis further indicates that the predictive behavior of the model is strongly scenario-dependent, with higher-load operation within the calibrated range amplifying parameter perturbations. Overall, the proposed MTEC-SOC framework provides accurate SOC estimation and physically interpretable insight within the evaluated dataset and operating conditions, offering potential guidance for battery management and energy optimization in intelligent mobile terminals. Full article

Data centers are critical digital infrastructure supporting cloud computing, artificial intelligence, and global information services. Despite their high-reliability design, they remain vulnerable to fire incidents due to continuous operation, high electrical loads, dense power systems, and the increasing use of lithium-ion batteries. Although such events are rare, their consequences can be severe, including service disruption, equipment damage, financial loss, and risks to data integrity. This study presents a systematic literature review of fire safety risk management frameworks in data centers, following PRISMA guidelines. Peer-reviewed studies published between 2020 and 2025 were retrieved from Scopus and Web of Science, screened, and appraised using structured quality criteria. Twelve empirical studies were synthesized and benchmarked against NFPA 75 and NFPA 76 standards. The findings are organized into three domains: Strategic Management, Fire Risk, and Fire Preparedness. The results show a strong focus on technical prevention and electrical hazards, while organizational readiness, emergency response, and recovery remain underexplored. Benchmarking indicates that industry standards adopt a more comprehensive lifecycle approach than the academic literature. This study reframes data center fire safety as a socio-technical reliability system and highlights critical gaps, providing a foundation for future research and improved fire safety governance and resilience. Full article

The breeding blanket is a key component of tokamaks, primarily responsible for extracting heat from fusion reactions and for tritium breeding, which is essential to ensure a fusion reactor’s fuel self-sufficiency. Recent technological advancements have led to the development of Dual-Cooled Lead–Lithium (DCLL) breeding blankets, which employ a liquid metal (specifically a Lead–Lithium eutectic alloy) as a heat transfer medium and tritium breeder, while helium gas is used to cool the structural components of the reactor. The interaction between the moving electrically conducting fluid and the strong magnetic field in the tokamak environment leads to magnetohydrodynamic (MHD) effects. The latter are characterized by the induction of eddy currents within the fluid and resulting Lorentz forces generated by their interaction with the magnetic field, which cause additional pressure losses and reduce heat transfer efficiency. This work investigates the pressure drop experienced by a Lead–Lithium flow within a rectangular section conduit under the action of an external, uniform magnetic field of different intensities. An analytical model was developed to estimate the total MHD-induced pressure losses along the channel for different values of the external magnetic field intensity and then benchmarked against relative computational fluid dynamics (CFD) simulations carried out using COMSOL Multiphysics. This comparison allowed the validation of the analytical predictions as well as a better understanding of the influence of the applied magnetic field intensity on the overall pressure drop. Therefore, the aim of the analytical model is to provide analytical tools for reasonably accurate estimations of MHD pressure losses suitable for future preliminary design purposes. Full article

Thin-film lithium niobate electro-optic modulators exhibit outstanding advantages such as large bandwidth, low insertion loss, and low half-wave voltage, demonstrating broad application prospects. However, due to internal defects in lithium niobate crystals, modulators exhibit electro-optic relaxation phenomena, with the relaxation time of thin-film structures being reduced by more than two orders of magnitude compared to bulk materials. In this study, we fitted and simulated the electro-optic relaxation behavior of thin-film lithium niobate modulators based on RC circuit model, effectively explaining their time-domain response characteristics under low-frequency conditions. By comparing thin-film modulators with and without silica cladding structures, the fitting results indicate that the relaxation time of modulators with cladding is approximately 11.9 ms, showing positive DC drift, whereas the relaxation time of modulators without cladding is significantly shortened to about 88.6 μs and exhibits negative DC drift. Additionally, the enhancement of optical intensity alters the photoconductivity of the material, thereby affecting its low-frequency electro-optic response behavior. This research provides important ideas for the design and optimization of next-generation integrated lithium niobate photonic modulators with high stability and controllability. Full article

Lithium remains endorsed as first-line treatment for bipolar disorders across major clinical guidelines, yet robust evidence demonstrates its progressive decline in use in psychiatric practice across numerous countries. To justify this decline, concerns regarding lithium’s efficacy, safety profile, and monitoring requirements are frequently cited. Yet these apprehensions largely stem from an insufficient understanding of lithium’s clinical uses. In fact, when patients are selected for lithium stabilization according to a characteristic clinical profile and not just a bipolar verdict, lithium continues demonstrating good efficacy compared to all other psychiatric medications currently available. Moreover, after sufficient clinician and patient education regarding lithium stabilization principles, monitoring requirements stop being burdensome. Furthermore, among lithium-responsive patients, adverse effects are typically mild and clinically manageable, except for glomerular filtration rate decline, which tends to develop after decades of continuous administration. Thus, it might be possible to reverse this unfortunate decline in lithium’s use by teaching clinicians to identify the patient profile responsive to lithium stabilization and by implementing educational programs regarding optimal lithium utilization for psychiatrists, patients, and their families. Furthermore, it is worth investigating intermittent lithium administration to mitigate renal complications. Full article

An improved optimizer based on projection-iterative methods (IPIMO) is proposed to address the optimal configuration problem of multi-type energy storage systems (MT-ESS), with the objective of achieving synergistic minimization of comprehensive costs, including both investment and operational expenditures. A comprehensive energy system model is established, integrating photovoltaic power, wind power, and six typical energy storage technologies—lithium-ion battery, flywheel energy storage, supercapacitors, valve-regulated lead-acid battery, compressed air energy storage, and redox flow battery. Four typical operational scenarios are designed to validate the adaptability and robustness of the algorithm. A systematic evaluation of IPIMO’s comprehensive performance is conducted by comparing it with the weighted average method (WA), the single-energy storage optimization method (SEO), the projection-iterative-methods-based optimizer algorithm (PIMO), and the genetic algorithm (GA). Simulation results demonstrate that IPIMO exhibits superior convergence performance, achieving stable convergence rapidly and significantly outperforming PIMO and GA. Moreover, IPIMO achieves the lowest total cost across all four scenarios, with an average of $46,837, representing reductions of 6.54% compared to the benchmark weighted average method and 11.8% compared to the SEO. Additionally, IPIMO adaptively adjusts the allocation ratios of energy storage types based on scenario characteristics, prioritizing energy-type storage in stable scenarios while increasing the proportion of fast-response storage to 49.1% in fluctuating scenarios, thereby demonstrating its strong scenario adaptability. Full article

Nickel-oxide-based anodic electrochromic materials are extensively utilized as counter electrodes in smart window systems due to their reversible optical response during ion insertion and extraction. This study systematically investigates the influence of substrate temperature on the electrochromic properties of sputtered nickel-tungsten oxide thin films. The deposited thin films exhibit an amorphous structure. An increase in substrate temperature results in a decrease in nickel-vacancy concentration. Raman spectroscopy verifies the amorphous nature. Films deposited at lower substrate temperatures exhibit superior electrochromic performance, characterized by improved optical contrast of 64% and rapid coloration (2.21 s) and bleaching (0.93 s) dynamics. The enhanced performance is ascribed to the disordered amorphous structure and the existence of enough nickel vacancies, which collectively facilitate efficient and reversible lithium-ion transfer. This study illustrates that meticulous regulation of substrate temperature is an effective method for adjusting the microstructure and defect chemistry of nickel–tungsten oxide thin films, rendering them appropriate as effective counter electrodes for energy-efficient smart window applications. Full article

Background/Objectives: Management of bipolar disorder is marked by variability in lithium response, with responders constituting a distinct clinical subgroup. Although pharmacogenetic studies implicate polymorphisms in neuroplasticity-related genes (BDNF) and hypothalamic–pituitary–adrenal (HPA) axis regulators (NR3C1), the underlying biophysical mechanisms remain poorly characterized. This study aims to bridge this structural–mechanistic gap by quantifying the atomic-level effects of key lithium-response polymorphisms on protein–protein interaction stability and conformational dynamics. Methods: Variant sequences for BDNF rs6265 and NR3C1 rs56149945 were generated and structurally modeled with SWISS-MODEL. Protein–protein interaction analyses focused on the BDNF–TrkB and NR3C1–FKBP5 systems. Structural alignment and conformational comparisons were performed with ChimeraX and US-align, while interaction energetics were evaluated with PRODIGY and HawkDock. Conformational flexibility was assessed using CABS-flex through RMSF analysis. Results: Structural validation showed acceptable model quality. Binding analyses indicated stronger interactions in the variant complexes. In the BDNF–TrkB complex, binding affinity shifted from −13.8 to −15.1 kcal/mol with an ~8.5-fold lower dissociation constant, while the NR3C1–FKBP5 variant complex shifted from −16.3 to −18.8 kcal/mol with an ~65-fold lower dissociation constant. MM/GBSA calculations supported increased stability, with binding energies changing from −61.98 to −83.91 kcal/mol (BDNF–TrkB) and from −18.88 to −31.25 kcal/mol (NR3C1–FKBP5). Structural superposition showed high conservation of global folds (pruned RMSD 0.779 Å and 0.310 Å; TM-scores 0.753 and 0.967). RMSF profiles were largely overlapping, indicating localized interface adjustments rather than global conformational changes. Conclusions: These findings suggest that lithium-response polymorphisms may modulate protein–protein interaction stability while preserving overall structure, providing a structural framework for exploring genetic influences on lithium treatment response. Full article

In this work, we present a novel online acoustic sulfur hexafluoride (SF₆) monitoring system utilizing a miniaturized lithium niobate tuning fork (LNTF) sensor. The proposed system demonstrates enhanced stability and a broadband vibration–frequency response. The LNTF exhibits a fundamental resonance frequency of 32,901 Hz, and its quality factor (Q-factor) decreases from 19,700 to 18,300 as the SF₆ concentration increases at atmospheric pressure. Verification experiments at room temperature reveal a quantifiable correlation between the SF₆/N₂ mixture concentration ratio and the sensor’s mechanical impedance. Specifically, an impedance shift of 100 Ω corresponds to a concentration change of 0.0145 g/L. In air, with a signal integration time of 80 s, the measured noise voltage and current are 0.13 µV and 0.18 pA, respectively. These results underscore the potential of the LNTF as a compact, high-stability sensing platform for greenhouse gas monitoring in electrical infrastructure and industrial environments. Full article

Transcutaneous electrical nerve stimulation (TENS) is constrained by high skin impedance and unstable electrode contact. This study proposes a novel composite electrode system comprising a polyvinyl alcohol/silver (PVA/Ag) microneedle array and a highly conductive polyacrylamide/lithium chloride (PAAm/LiCl) hydrogel. The PVA/Ag microneedles (~365 µm in height, ~48 µm tip diameter) possess sufficient mechanical strength to penetrate the stratum corneum, establishing a low-resistance pathway. The complementary PAAm/LiCl hydrogel exhibits high conductivity (10.28 S/m) and mechanical flexibility, further optimizing the interface contact. The experimental results demonstrate that this composite system achieves low electrochemical impedance and induces stable, clear electromyographic responses in vivo. It effectively addresses the common issues of electrode detachment and signal attenuation associated with conventional electrodes, offering a promising hardware solution for efficient and comfortable wearable rehabilitation devices. Full article

The mechanical safety of lithium-ion batteries (LIBs) under dynamic impact has been recognized as a critical concern for electric vehicles. In this study, three experimental dynamic impact datasets of cylindrical LIBs were established through drop-weight tests, with each dataset capturing the effects of indenter geometry, impact repetition, and state of charge (SOC). Using these datasets, six representative machine learning (ML) models—including ANN, SVR, LSTM, TCN, RF, and XGBoost—were evaluated for predicting force–time responses and analyzing failure-related characteristics indicated by the synchronized voltage response. The results indicated that ensemble models (XGBoost and RF) provided the highest predictive accuracy (R² > 0.999) under the tested conditions, while temporal models (LSTM and TCN) effectively captured nonlinear time-dependent behavior. These findings demonstrate that ML-based prediction offers a rapid and reliable means for impact-response assessment and voltage-drop-based failure indication in cylindrical LIBs, supporting early-stage safety screening under the investigated impact conditions. Full article

This review synthesizes recent progress in modern energy storage technologies and proposes a selection-oriented comparison for power-system stabilization. Technologies are grouped into electrochemical, mechanical, chemical, and thermal storage, and evaluated using harmonized criteria (power and energy capability, response time, round-trip efficiency, lifetime, cost proxies, and maturity level). A comparative dataset and use-case mapping are used to link technology characteristics to grid services, with emphasis on voltage support, operational durability, and waste-heat utilization. The analysis highlights pumped-storage hydropower as the most robust option for long-duration, high-capacity applications, while battery energy storage systems are best suited for fast ancillary services, provided that cycle life, safety, and system integration constraints are met. Finally, the review discusses current technology trends (e.g., LFP and sodium-ion deployment, solid-state development, and commercialization barriers for lithium-sulfur) and identifies evidence-based directions for future research and deployment. Full article

Recent decades have seen substantial growth in the demand for lithium-ion batteries (LIBs); as a result, the number of gigafactories is increasing. The power systems of these gigafactories are the most important parts of these installations, as they are directly responsible for energy efficiency, operational cost, and sustainable growth of the LIB industry. This necessitates the need for comprehensive studies of power consumption in a gigafactory during the LIB manufacturing process. This paper presents a detailed review of the state-of-the-art of different parts and components of power systems in gigafactories, and power consumption estimation during cell production. This research analyzes the existing components of a power system, including power sources, different power distribution mechanisms, various power equipment, thermal management strategies, failure analysis methods, and several technologies for regenerative functions. The analysis of the above-mentioned components, systems, and technologies will enable us to understand the cumulative power consumption profile of the gigafactory, including the power consumption at each step of the production process, for normal non-production operations, like powering and lighting the facility, and for the complex and highly sophisticated power distribution system. The outcomes of this research paper highlight the importance of an optimized power system for the gigafactory, with maximum possible efficiency and minimal power losses during transmission, distribution, operational stages, and the cell formation process. This paper also helps to understand the shortcomings in existing systems and technologies, suggests improvements, and provides targets for future research directions. Full article

To address the inherent limitations of Cu₂Se as a lithium-ion battery (LIB) anode, a Cu₂Se/MnSe@C composite was rationally designed and synthesized via selenization of a CuMn bimetallic metal–organic framework (MOF) precursor. This synthesis strategy integrates carbon composite engineering and heterogeneous structure construction, achieving in situ formation of Cu₂Se/MnSe heterogeneous nanoparticles anchored on amorphous carbon nanosheets. Structural characterizations confirm the successful construction of well-defined Cu₂Se/MnSe interfaces and uniform dispersion of selenide components, with Mn introduction inducing regulated electron transfer between Cu₂Se and MnSe. Electrochemical evaluations demonstrate that the Cu₂Se/MnSe@C composite exhibits a significantly enhanced lithium storage performance compared to single-component Cu₂Se@C, including higher specific capacity and superior rate capability. Mechanistic studies reveal that the synergistic effects of the carbon matrix (enhancing electrical conductivity and mitigating volume expansion) and the Cu₂Se/MnSe heterogeneous interface (lowering charge transfer resistance, accelerating Li⁺ diffusion, and boosting pseudocapacitive contribution) are responsible for the performance enhancement. Moreover, Cu₂Se/MnSe@C||LiFePO₄ full cells deliver a stable average operating voltage and reliable cycling stability, validating the composite’s practical application potential. Full article

This work investigates the reactive crystallization of lithium carbonate (Li₂CO₃) by rapidly mixing concentrated aqueous solutions of LiCl (3.0–4.0 M) and Na₂CO₃ (1.5–2.0 M) at 65 °C, using focused beam reflectance measurement (FBRM) for online, in situ monitoring. The effect of low concentrations of poly(acrylic acid) (PAA), sodium hexametaphosphate (SHMP), and sodium tripolyphosphate (STPP) on nucleation and growth dynamics was systematically analyzed. The results show that the process is dominated by an intense initial supersaturation pulse, which governs early nucleation and subsequent population restructuring through growth and aggregation. Additives significantly modify the nucleation-growth coupling: PAA exhibits concentration- and time-dependent behavior, suppressing the detectable fines population and promoting consolidation into coarse fractions under high supersaturation; SHMP acts as a strong kinetic inhibitor, markedly reducing nucleation and, to a greater extent, growth; while STPP exhibits an intermediate, dose-dependent response, maintaining nucleation but limiting effective growth at high concentrations. Scanning electron microscopy observations confirm the formation of spherulitic Li₂CO₃ aggregates in all cases, with compactness and radial organization dependent on the additive. These results demonstrate that targeted additive selection allows for precise control of population dynamics and solid properties in reactive crystallization systems, within the investigated high-supersaturation concentration window, with useful mechanistic guidance for the design and control of Li₂CO₃ precipitation processes. Full article