This paper introduces a method for modeling the entire aggregated electric vehicle(EV)charging process and analyzing its dispatchable capabilities.The methodology involves developing a model for aggregated EV charging...This paper introduces a method for modeling the entire aggregated electric vehicle(EV)charging process and analyzing its dispatchable capabilities.The methodology involves developing a model for aggregated EV charging at the charging station level,estimating its physical dispatchable capability,determining its economic dispatchable capability under economic incentives,modeling its participation in the grid,and investigating the effects of different scenarios and EV penetration on the aggregated load dispatch and dispatchable capability.The results indicate that using economic dispatchable capability reduces charging prices by 9.7%compared to physical dispatchable capability and 9.3%compared to disorderly charging.Additionally,the peak-to-valley difference is reduced by 64.6%when applying economic dispatchable capability with 20%EV penetration and residential base load,compared to disorderly charging.展开更多
Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or lower.However,the key capability o...Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or lower.However,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely reported.Herein,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized via a high temperature shock method.Such a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1) at 2 A g^(−1))at−60℃,outperforming all reported SIB anode materials.Coupled with a Na_(3)V_(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1) at−40°C.Based on this work,a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.展开更多
Lithium-ion batteries(LIBs)are an electrochemical energy storage technology that has been widely used for portable electrical devices,electric vehicles,and grid storage,etc.To satisfy the demand for user convenience e...Lithium-ion batteries(LIBs)are an electrochemical energy storage technology that has been widely used for portable electrical devices,electric vehicles,and grid storage,etc.To satisfy the demand for user convenience especially for electric vehicles,the development of a fast-charging technology for LIBs has become a critical focus.In commercial LIBs,the slow kinetics of Li+intercalation into the graphite anode from the electrolyte solution is known as the main restriction for fast-charging.We summarize the recent advances in obtaining fast-charging graphite-based anodes,mainly involving modifications of the electrolyte solution and graphite anode.Specifically,strategies for increasing the ionic conductivity and regulating the Li+solvation/desolvation state in the electrolyte solution,as well as optimizing the fabrication and the intrinsic activity of graphite-based anodes are discussed in detail.This review considers practical ways to obtain fast Li+intercalation kinetics into a graphite anode from the electrolyte as well as analysing progress in the commercialization of fast-charging LIBs.展开更多
Potential high-temperature risks exist in heat-prone components of electric moped charging devices,such as sockets,interfaces,and controllers.Traditional detection methods have limitations in terms of real-time perfor...Potential high-temperature risks exist in heat-prone components of electric moped charging devices,such as sockets,interfaces,and controllers.Traditional detection methods have limitations in terms of real-time performance and monitoring scope.To address this,a temperature detection method based on infrared image processing has been proposed:utilizing the median filtering algorithm to denoise the original infrared image,then applying an image segmentation algorithm to divide the image.展开更多
In China,electric vehicle(EV)fast-charging power has quadrupled in the past five years,progressing toward 10-minute ultrafast charging.This rapid increase raises concerns about the impact on the power grid including i...In China,electric vehicle(EV)fast-charging power has quadrupled in the past five years,progressing toward 10-minute ultrafast charging.This rapid increase raises concerns about the impact on the power grid including increased peak power demand and the need for substantial upgrades to power infrastruc-ture.Here,we introduce an integrated model to assess fast and ultrafast charging impacts for represen-tative charging stations in China,combining real-world charging patterns and detailed station optimization models.We find that larger stations with 12 or more chargers experience modest peak power increases of less than 30%when fast-charging power is doubled,primarily because shorter charg-ing sessions are less likely to overlap.For more typical stations(e.g.,8-9 chargers and 120 kW·charger^(−1)),upgrading chargers to 350-550 kW while allowing managed dynamic waiting strategies(of∼1 minute)can reduce overall charging times to∼9 minutes.At stations,deploying battery storage and/or expanding transformers can help manage future increases in station loads,yet the primary device cost of the former is∼4 times higher than that of the latter.Our results offer insights for charging infrastructure planning,EV-grid interactions,and associated policymaking.展开更多
Aiming at the problem of increasing the peak-to-valley difference of grid load and the rising cost of user charging caused by the disorderly charging of large-scale electric vehicles,this paper proposes a coordinated ...Aiming at the problem of increasing the peak-to-valley difference of grid load and the rising cost of user charging caused by the disorderly charging of large-scale electric vehicles,this paper proposes a coordinated charging scheduling strategy for multiple types of electric vehicles based on the degree of urgency of vehicle use.First,considering the range loss characteristics,dynamic time-sharing tariff mechanism,and user incentive policy in the lowtemperature environment of northern winter,a differentiated charging model is constructed for four types of vehicles:family cars,official cars,buses,and cabs.Then,we innovatively introduce the urgency parameter of charging demand for multiple types of vehicles and dynamically divide the emergency and non-emergency charging modes according to the difference between the regular charging capacity and the user’s minimum power demand.When the conventional charging capacity is less than the minimum power demand of the vehicle within the specified time,it is the emergency vehicle demand,and this type of vehicle is immediately charged in fast charging mode after connecting to the grid.On the contrary,it is a non-emergency demand,and the vehicle is connected to the grid to choose the appropriate time to charge in conventional charging mode.Finally,by optimizing the objective function to minimize the peakto-valley difference between the grid and the vehicle owner’s charging cost,and designing the charging continuity constraints to avoid battery damage,it ensures that the vehicle is efficiently dispatched under the premise of meeting the minimum power demand.Simulation results show that the proposed charging strategy can reduce the charging cost of vehicle owners by 26.33%,reduce the peak-to-valley difference rate of the grid by 29.8%,and significantly alleviate the congestion problem during peak load hours,compared with the disordered charging mode,while ensuring that the electric vehicles are not overcharged and meet the electricity demand of vehicle owners.This paper solves the problems of the existing research on the singularity of vehicle models and the lack of environmental adaptability and provides both economic and practical solutions for the cooperative optimization of electric vehicles and power grids in multiple scenarios.展开更多
High-power direct current fast charging(DC-HPC),particularly for megawatt-level charging currents(≥1000 A),is expected to significantly reduce charging time and improve electric vehicle durability,despite the risk of...High-power direct current fast charging(DC-HPC),particularly for megawatt-level charging currents(≥1000 A),is expected to significantly reduce charging time and improve electric vehicle durability,despite the risk of instantaneous thermal shocks.Conventional cooling methods,which separately transmit current and heat,struggle to achieve both flexible maneuverability and high-efficiency cooling.In this study,we present a synergetic cooling and transmission strategy using a gallium-based liquid metal flexible charging connector(LMFCC),which efficiently dissipates ultra-high heat flux while simultaneously carrying superhigh current.The LMFCC exhibits exceptional flexible operability(bending radius of 2 cm)and transmission stability even under significant deformation owing to the excellent liquidity and conductivity of liquid metal(LM).These properties are markedly better than those of solid metal connector.A compact induction electromagnet-driven method is optimized to significantly increase the LM flow rate and the active cooling capacity,resulting in sudden low temperature(<16℃at 1000 A).This synergetic cooling and charging strategy are expected to enable ultrahigh-heat-flux thermal management and accelerate development of the electric vehicle industry.展开更多
In this work,Langevin dynamics simulations were carried out to thoroughly investigate the swapping process of composite knots under tension in a cuboid nanochannel.From our analysis,the free energy profiles of knot sw...In this work,Langevin dynamics simulations were carried out to thoroughly investigate the swapping process of composite knots under tension in a cuboid nanochannel.From our analysis,the free energy profiles of knot swapping under different conditions were extracted from the overall probability distribution of the relative distance between the centers of composite knots.In addition,the impact of the stretching force,confinement size,and bending stiffness on the free energy profiles was directly identified.Especially,the influence of topology structure is for the first time reported.The increasing stretching force in a fixed confinement or the confinement size under a constant stretching force does not alter their respective equilibrium populations at the separate state and the entangled state.In contrast,a bending stiffness larger than 15 enhanced the formation of the entangled state.The topology structure of the 51knot,which was different from the 52knot,resulted in forming a metastable state in the free energy profiles.The increasing stretching forces yielded an enhancement of the following free energy barrier.展开更多
Harnessing the potential of graphite is key to fast charging at 4C(fully charged within 15 minutes)for electric vehicles.However,graphite is subject to lithium dendrite growth during charging,leading to short circuits...Harnessing the potential of graphite is key to fast charging at 4C(fully charged within 15 minutes)for electric vehicles.However,graphite is subject to lithium dendrite growth during charging,leading to short circuits and battery failures,which is one of the biggest problems for batteries[1-4].Therefore,quickly identifying the lithium dendrites and different types of dendrites on the graphite surface can quickly help analyze the state of graphite and design good charging protocols.展开更多
The accelerated global adoption of electric vehicles(EVs)is driving significant expansion and increasing complexity within the EV charging infrastructure,consequently presenting novel and pressing cybersecurity challe...The accelerated global adoption of electric vehicles(EVs)is driving significant expansion and increasing complexity within the EV charging infrastructure,consequently presenting novel and pressing cybersecurity challenges.While considerable effort has focused on preventative cybersecurity measures,a critical deficiency persists in structured methodologies for digital forensic analysis following security incidents,a gap exacerbated by system heterogeneity,distributed digital evidence,and inconsistent logging practices which hinder effective incident reconstruction and attribution.This paper addresses this critical need by proposing a novel,data-driven forensic framework tailored to the EV charging infrastructure,focusing on the systematic identification,classification,and correlation of diverse digital evidence across its physical,network,and application layers.Our methodology integrates open-source intelligence(OSINT)with advanced system modeling based on a three-layer cyber-physical system architecture to comprehensively map potential evidentiary sources.Key contributions include a comprehensive taxonomy of cybersecurity threats pertinent to EV charging ecosystems,detailed mappings between these threats and the resultant digital evidence to guide targeted investigations,the formulation of adaptable forensic investigation workflows for various incident scenarios,and a critical analysis of significant gaps in digital evidence availability within current EV charging systems,highlighting limitations in forensic readiness.The practical application and utility of this method are demonstrated through illustrative case studies involving both empirically-derived and virtual incident scenarios.The proposed datadriven approach is designed to significantly enhance digital forensic capabilities,support more effective incident response,strengthen compliance with emerging cybersecurity regulations,and ultimately contribute to bolstering the overall security,resilience,and trustworthiness of this increasingly vital critical infrastructure.展开更多
Automated guided vehicles(AGVs)are key equipment in automated container terminals(ACTs),and their operational efficiency can be impacted by conflicts and battery swapping.Additionally,AGVs have bidirectional transport...Automated guided vehicles(AGVs)are key equipment in automated container terminals(ACTs),and their operational efficiency can be impacted by conflicts and battery swapping.Additionally,AGVs have bidirectional transportation capabilities,allowing them tomove in the opposite directionwithout turning around,which helps reduce transportation time.This paper aims at the problem of AGV scheduling and bidirectional conflict-free routing with battery swapping in automated terminals.A bi-level mixed integer programming(MIP)model is proposed,taking into account task assignment,bidirectional conflict-free routing,and battery swapping.The upper model focuses on container task assignment and AGV battery swapping planning,while the lower model ensures conflict-free movement of AGVs.A double-threshold battery swapping strategy is introduced,allowing AGVs to utilize waiting time for loading for battery swapping.An improved differential evolution variable neighborhood search(IDE-VNS)algorithm is developed to solve the bi-level MIP model,aiming to minimize the completion time of all jobs.Experimental results demonstrate that compared to the differential evolution(DE)algorithm and the genetic algorithm(GA),the IDEVNS algorithmreduces fitness values by 44.49% and 45.22%,though it does increase computation time by 56.28% and 62.03%,respectively.Bidirectional transportation reduces the fitness value by an average of 10.97% when the container scale is small.As the container scale increases,the fitness value of bidirectional transportation gradually approaches that of unidirectional transportation.The results further show that the double-threshold battery swapping strategy enhances AGV utilization and reduces the fitness value.展开更多
Developing fast-charging lithium-ion batteries(LIBs)that feature high energy density is critical for the scalable application of electric vehicles.Iron vanadate(FVO)holds great potential as anode material in fast-char...Developing fast-charging lithium-ion batteries(LIBs)that feature high energy density is critical for the scalable application of electric vehicles.Iron vanadate(FVO)holds great potential as anode material in fast-charging LIBs because of its high theoretical specific capacity and the high natural abundance of its constituents.However,the capacity of FVO rapidly decays due to its low electrical conductivity.Herein,uniform FVO nanoparticles are grown in situ on ordered mesoporous carbon(CMK-3)support,forming a highly electrically conductive porous network,FVO/CMK-3.The structure of CMK-3 helps prevent agglomeration of FVO particles.The electrically conductive nature of CMK-3 can further enhance the electrical conductivity of FVO/CMK-3 and buffer the volume expansion of FVO particles during cycling processes.As a result,the FVO/CMK-3 displays excellent fast-charging performance of 364.6 mAh·g^(-1)capacity for 2500 cycles at 10 A·g^(-1)(with an ultralow average capacity loss per cycle of 0.003%)through a pseudocapacitive-dominant process.Moreover,the LiCoO_(2)//FVO/CMK-3 full cell achieves a high capacity of 100.2 mAh·g^(-1)and a high capacity retention(96.2%)after 200 cycles.The superior electrochemical performance demonstrates that FVO/CMK-3 is an ideal anode material candidate for fast-charging,stable LIBs with high energy density.展开更多
The global public HPC(high-power charging)network for EVs(electric vehicles)is rapidly expanding.This growth is crucial for supporting the increasing adoption of EVs but highlights the industry’s early stage.Regional...The global public HPC(high-power charging)network for EVs(electric vehicles)is rapidly expanding.This growth is crucial for supporting the increasing adoption of EVs but highlights the industry’s early stage.Regional maturity varies,with China leading due to strong government support,followed by Europe and the United States.A significant challenge is the lack of industry standards,causing inconsistencies in charger types and payment systems.Efforts are underway,to ensure interoperability and reliability.Interoperability is crucial for the success of EV HPC infrastructure,ensuring seamless integration among charge points,management systems,and service providers.Despite the use of protocols like the OCPP(Open Charge Point Protocol),variations in implementation create complexities.Ensuring uniform standards across the ecosystem is essential for reliability and efficiency.Vendor-specific error codes,which are more detailed than standardized codes,are vital for diagnosing issues but lack standardization,adding complexity.Addressing these challenges is key to supporting widespread EV adoption and enhancing user experience.To provide a compelling driver value proposition,EV charging services must be reliable and seamless.The operations and maintenance of the HPC network must be cost-effective and leverage the intelligence of the integrated ecosystem.The technical complexity of managing high-power DC charging,combined with diverse authentication and payment systems,results in numerous potential issues.Moving from reactive to predictive maintenance is essential for undisrupted operations and a smooth driver experience.Shell’s Intelligent Operations Technology Strategy incorporates GenAI elements in its advanced analytics and operational performance management tools.By ingesting big data from multiple sources across the EV ecosystem,Shell engineers can perform detailed pattern recognition and targeted troubleshooting.Monitoring,configurable alerting,and remote fixing based on auto-healing and targeted auto-allocation enhance charger availability and reduce downtime.This automation has evolved Shell’s maintenance and operations strategy from reactive to predictive,improving overall charger performance and user satisfaction.Key achievements include transitioning to prescriptive and preventive asset management approaches,significantly improving uptime and charging experience,and increasing commercial value through cost reduction and enhanced revenue.Future challenges include evolving OCPP,integrating data from non-OCPP systems,and ensuring interoperability across diverse systems.Standardization and cross-collaboration within the industry are essential for smooth interoperability,higher uptime,and increased CSR(charging success rate).Technological innovations will further shape the industry,promoting stabilization and efficiency as it matures.展开更多
Ni-rich cathode materials are essential for enhancing the performance of lithium-ion batteries(LIBs)in electric vehicles(EVs),particularly concerning extreme fast charging(XFC)and durability.While much of studies shin...Ni-rich cathode materials are essential for enhancing the performance of lithium-ion batteries(LIBs)in electric vehicles(EVs),particularly concerning extreme fast charging(XFC)and durability.While much of studies shine a spotlight on Li plating on the anode to improve rate capability,there is a critical lack of studies addressing the combination of kinetic improvements and mechanical strength of cathode materials under XFC conditions.In this work,Mg/Ti co-doped Ni-rich LiNi_(0.88)Co_(0.09)Mn_(0.03)O_(2)(MT-NCM)was successfully synthesized to address structural challenges associated with high-rate cycling.The results demonstrate that the stronger Ti–O bond contributes to the enhanced mechanical strength of secondary grains,which effectively alleviates microcrack formation during fast charging.Additionally,the detrimental phase transitions and internal strain as well as parasitic reactions of MT-NCM are significantly suppressed due to the synergistic effect of the dual dopants,ensuring excellent Li-ion transport kinetics compared to pristine NCM(P-NCM).Consequently,MT-NCM achieves remarkable high-rate cycling performance,retaining 88.04%of its initial capacity at 5 C and superior discharge capacity over 175 mA h g^(−1)even at 10 C.This work highlights the potential of optimizing the kinetic-mechanical properties of Ni-rich cathodes,providing a viable approach for the development of XFC LIBs with improved durability for EV applications.展开更多
Poor Li plating reversibility and high thermal runaway risks are key challenges for fast charging lithiumion batteries with graphite anodes.Herein,a dielectric and fire-resistant separator based on hybrid nanofibers o...Poor Li plating reversibility and high thermal runaway risks are key challenges for fast charging lithiumion batteries with graphite anodes.Herein,a dielectric and fire-resistant separator based on hybrid nanofibers of barium sulfate(BS)and bacterial cellulose(BC)is developed to synchronously enhance the battery's fast charging and thermal-safety performances.The regulation mechanism of the dielectric BS/BC separator in enhancing the Li^(+)ion transport and Li plating reversibility is revealed.(1)The Max-Wagner polarization electric field of the dielectric BS/BC separator can accelerate the desolvation of solvated Li^(+)ions,enhancing their transport kinetics.(2)Moreover,due to the charge balancing effect,the dielectric BS/BC separator homogenizes the electric field/Li^(+)ion flux at the graphite anode-separator interface,facilitating uniform Li plating and suppressing Li dendrite growth.Consequently,the fast-charge graphite anode with the BS/BC separator shows higher Coulombic efficiency(99.0%vs.96.9%)and longer cycling lifespan(100 cycles vs.59 cycles)than that with the polypropylene(PP)separator in the constantlithiation cycling test at 2 mA cm^(-2).The high-loading LiFePO4(15.5 mg cm^(-2))//graphite(7.5 mg cm^(-2))full cell with the BS/BC separator exhibits excellent fast charging performance,retaining 70%of its capacity after 500 cycles at a high rate of 2C,which is significantly better than that of the cell with the PP separator(retaining only 27%of its capacity after 500 cycles).More importantly,the thermally stable BS/BC separator effectively elevates the critical temperature and reduces the heat release rate during thermal runaway,thereby significantly enhancing the battery's safety.展开更多
The properties of electrolytes are critical for fast-charging and stable-cycling applications in lithium metal batteries(LMBs).However,the slow kinetics of Li^(+)transport and desolvation in commercial carbonate elect...The properties of electrolytes are critical for fast-charging and stable-cycling applications in lithium metal batteries(LMBs).However,the slow kinetics of Li^(+)transport and desolvation in commercial carbonate electrolytes,cou pled with the formation of unstable solid electrolyte interphases(SEI),exacerbate the degradation of LMB performance at high current densities.Herein,we propose a versatile electrolyte design strategy that incorporates cyclohexyl methyl ether(CME)as a co-solvent to reshape the Li^(+)solvation environment by the steric-hindrance effect of bulky molecules and their competitive coordination with other solvent molecules.Simulation calculations and spectral analysis demonstrate that the addition of CME molecules reduces the involvement of other solvent molecules in the Li solvation sheath and promotes the formation of Li^(+)-PF_(6)^(-)coordination,thereby accelerating Li^(+)transport kinetics.Additionally,this electrolyte composition improves Li^(+)desolvation kinetics and fosters the formation of inorganic-rich SEI,ensuring cycle stability under fast charging.Consequently,the Li‖LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)battery with the modified electrolyte retains 82% of its initial capacity after 463 cycles at 1 C.Even under the extreme fast-charging condition of 5 C,the battery can maintain 80% capacity retention after 173 cycles.This work provides a promising approach for the development of highperformance LMBs by modulating solvation environment of electrolytes.展开更多
High-nickel ternary silicon-carbon lithium-ion batteries,which use silicon-carbon materials as anodes and high-nickel ternary materials as cathodes,have already been commercialized as power batteries.The increasing de...High-nickel ternary silicon-carbon lithium-ion batteries,which use silicon-carbon materials as anodes and high-nickel ternary materials as cathodes,have already been commercialized as power batteries.The increasing demand for high-energy density and rapid charging characteristics has heightened the urgency of improving their fast charging cycle performance while establishing degradation mechanisms.Based on a pouch battery design with an energy density of 285 Wh·kg^(-1),this work studied 3 Ah pouch batteries for fast charging cycles ranging from 0.5C to 3C.Non-destructive techniques,such as differential voltage,incremental capacity analysis,and electrochemical impedance spectroscopy,were employed to investigate the effects of charging rates on battery cycling performance and to establish the degradation mechanisms.The experimental results indicated that capacity diving was observed at all charging rates.However,at lower rates(0.5C-2C),more cycles were achieved,while at higher rates(2C-3C),the cycle life remained relatively stable.Computed tomography,electrochemical performance analysis,and physicochemical characterizations were obtained,using scanning electron microscopy with energy dispersive spectroscopy,X-ray diffraction,X-ray photoelectron spectroscopy,and inductively coupled plasma optical emission spectrometry.The mechanisms of capacity decrease during 3C fast charging cycles were investigated.It is proposed that the primary causes of capacity diving during 3C fast charging are the degradation of SiOx,anode polarization,and the simultaneous dissolution of metal ions in the cathode which were deposited at the anode,resulting the continuous growth and remodeling of the SEI membrane at the anode,thereby promoting more serious side reactions.展开更多
Sodium metal batteries(SMBs)are promising candidates for next-generation energy storage devices owing to their excellent safety performance and natural abunda nce of sodium.However,the insurmountable obstacles of dend...Sodium metal batteries(SMBs)are promising candidates for next-generation energy storage devices owing to their excellent safety performance and natural abunda nce of sodium.However,the insurmountable obstacles of dendrite formation and quick capacity decay are caused by an unstable and inhomogeneous solid electrolyte interphase that resulted from the immediate interactions between the Na metal anode and organic liquid electrolyte.Herein,a customised glass fibre separator coupled with chitosan(CS@GF)was developed to modulate the sodium ion(Na^(+))flux.The CS@GF separator facilitates the Na+homogeneous deposition on the anode side through redistribution at the chitosan polyactive sites and by inhibiting the decomposition of the electrolyte to robust solid electrolyte interphase(SEI)formation.Multiphysics simulations show that chitosan incorporated into SMBs through the separator can make the local electric field around the anode uniform,thus facilitating the transfer of cations.Na|Na symmetric cells utilising a CS@GF separator exhibited an outstanding cycle stability of over 600 h(0.5 mA cm^(-2)).Meanwhile,the Na|Na_(3)V_(5)(PO_(4))_(3)full cell exhibited excellent fast-charging performance(93.47%capacity retention after 1500 cycles at 5C).This study presents a promising strategy for inhibiting dendrite growth and realizes stable Na metal batteries,which significantly boosts the development of high-performance SMBs.展开更多
Electric vehicles are pivotal in the global shift toward decarbonizing road transport,with lithium-ion batteries at the heart of this technological evolution.However,the pursuit of batteries capable of extremely fast ...Electric vehicles are pivotal in the global shift toward decarbonizing road transport,with lithium-ion batteries at the heart of this technological evolution.However,the pursuit of batteries capable of extremely fast charging that also satisfy high energy and safety criteria,poses a significant challenge to current lithium-ion batteries technologies.Additionally,the increasing demand for aluminum(Al)and copper(Cu)in electrification,solar energy technologies,and vehicle light-eighting is driving these metals toward near-critical status in the medium term.This study introduces metalized polythylene terephthalate(mPET)polymer films by depositing an Al or Cu thin layer onto two sides of a polyethylene terephthalate film—named mPET/Al and mPET/Cu,as lightweight,cost-effective alternatives to traditional metal current collectors in lithium-ion batteries.We have fabricated current collectors that significantly reduce weight(by 73%),thickness(by 33%),and cost(by 85%)compared with traditional metal foil counterparts.These advancements have the potential to enhance energy density to 280 Wh kg^(-1) at the electrode level under 10-min charging at 6 C.Through testing,including a novel extremely fast charging protocol across various C-rates and long-term cycling(up to 1000 cycles)in different cell configurations,the superior performance of these metalized polymer films has been demonstrated.Notably,mPET/Cu and mPET/Al films exhibited comparable capacities to conventional cells under extremely fast charging,with the mPET cells showing a 27%improvement in energy density at 6 C and maintaining significant energy density after 1000 cycles.This study underscores the potential of mPET films to revolutionize the roll-to-roll battery manufacturing process and significantly advance the performance metrics of lithium-ion batteries in electric vehicles applications.展开更多
Electric Vehicle Charging Systems(EVCS)are increasingly vulnerable to cybersecurity threats as they integrate deeply into smart grids and Internet ofThings(IoT)environments,raising significant security challenges.Most...Electric Vehicle Charging Systems(EVCS)are increasingly vulnerable to cybersecurity threats as they integrate deeply into smart grids and Internet ofThings(IoT)environments,raising significant security challenges.Most existing research primarily emphasizes network-level anomaly detection,leaving critical vulnerabilities at the host level underexplored.This study introduces a novel forensic analysis framework leveraging host-level data,including system logs,kernel events,and Hardware Performance Counters(HPC),to detect and analyze sophisticated cyberattacks such as cryptojacking,Denial-of-Service(DoS),and reconnaissance activities targeting EVCS.Using comprehensive forensic analysis and machine learning models,the proposed framework significantly outperforms existing methods,achieving an accuracy of 98.81%.The findings offer insights into distinct behavioral signatures associated with specific cyber threats,enabling improved cybersecurity strategies and actionable recommendations for robust EVCS infrastructure protection.展开更多
基金State Grid Henan Power Company Science and Technology Project‘Key Technology and Demonstration Application of Multi-Domain Electric Vehicle Aggregated Charging Load Dispatch’(5217L0240003).
文摘This paper introduces a method for modeling the entire aggregated electric vehicle(EV)charging process and analyzing its dispatchable capabilities.The methodology involves developing a model for aggregated EV charging at the charging station level,estimating its physical dispatchable capability,determining its economic dispatchable capability under economic incentives,modeling its participation in the grid,and investigating the effects of different scenarios and EV penetration on the aggregated load dispatch and dispatchable capability.The results indicate that using economic dispatchable capability reduces charging prices by 9.7%compared to physical dispatchable capability and 9.3%compared to disorderly charging.Additionally,the peak-to-valley difference is reduced by 64.6%when applying economic dispatchable capability with 20%EV penetration and residential base load,compared to disorderly charging.
基金supported from Science and Technology Development Program of Jilin Province(Nos.20240101128JC,20230402058GH)National Natural Science Foundation of China(No.52130101).
文摘Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or lower.However,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely reported.Herein,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized via a high temperature shock method.Such a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1) at 2 A g^(−1))at−60℃,outperforming all reported SIB anode materials.Coupled with a Na_(3)V_(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1) at−40°C.Based on this work,a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.
文摘Lithium-ion batteries(LIBs)are an electrochemical energy storage technology that has been widely used for portable electrical devices,electric vehicles,and grid storage,etc.To satisfy the demand for user convenience especially for electric vehicles,the development of a fast-charging technology for LIBs has become a critical focus.In commercial LIBs,the slow kinetics of Li+intercalation into the graphite anode from the electrolyte solution is known as the main restriction for fast-charging.We summarize the recent advances in obtaining fast-charging graphite-based anodes,mainly involving modifications of the electrolyte solution and graphite anode.Specifically,strategies for increasing the ionic conductivity and regulating the Li+solvation/desolvation state in the electrolyte solution,as well as optimizing the fabrication and the intrinsic activity of graphite-based anodes are discussed in detail.This review considers practical ways to obtain fast Li+intercalation kinetics into a graphite anode from the electrolyte as well as analysing progress in the commercialization of fast-charging LIBs.
基金supported by the National Key Research and Development Project of China(No.2023YFB3709605)the National Natural Science Foundation of China(No.62073193)the National College Student Innovation Training Program(No.202310422122)。
文摘Potential high-temperature risks exist in heat-prone components of electric moped charging devices,such as sockets,interfaces,and controllers.Traditional detection methods have limitations in terms of real-time performance and monitoring scope.To address this,a temperature detection method based on infrared image processing has been proposed:utilizing the median filtering algorithm to denoise the original infrared image,then applying an image segmentation algorithm to divide the image.
基金the support of the National Natural Science Foundation of China(72325006,72488101,and 72293601)the Sze Family Foundationthe Climate Imperative Foundation(#2024-001465)
文摘In China,electric vehicle(EV)fast-charging power has quadrupled in the past five years,progressing toward 10-minute ultrafast charging.This rapid increase raises concerns about the impact on the power grid including increased peak power demand and the need for substantial upgrades to power infrastruc-ture.Here,we introduce an integrated model to assess fast and ultrafast charging impacts for represen-tative charging stations in China,combining real-world charging patterns and detailed station optimization models.We find that larger stations with 12 or more chargers experience modest peak power increases of less than 30%when fast-charging power is doubled,primarily because shorter charg-ing sessions are less likely to overlap.For more typical stations(e.g.,8-9 chargers and 120 kW·charger^(−1)),upgrading chargers to 350-550 kW while allowing managed dynamic waiting strategies(of∼1 minute)can reduce overall charging times to∼9 minutes.At stations,deploying battery storage and/or expanding transformers can help manage future increases in station loads,yet the primary device cost of the former is∼4 times higher than that of the latter.Our results offer insights for charging infrastructure planning,EV-grid interactions,and associated policymaking.
基金funded by Science and Technology Project of SGCC(SGJLCC00KJJS2203595).
文摘Aiming at the problem of increasing the peak-to-valley difference of grid load and the rising cost of user charging caused by the disorderly charging of large-scale electric vehicles,this paper proposes a coordinated charging scheduling strategy for multiple types of electric vehicles based on the degree of urgency of vehicle use.First,considering the range loss characteristics,dynamic time-sharing tariff mechanism,and user incentive policy in the lowtemperature environment of northern winter,a differentiated charging model is constructed for four types of vehicles:family cars,official cars,buses,and cabs.Then,we innovatively introduce the urgency parameter of charging demand for multiple types of vehicles and dynamically divide the emergency and non-emergency charging modes according to the difference between the regular charging capacity and the user’s minimum power demand.When the conventional charging capacity is less than the minimum power demand of the vehicle within the specified time,it is the emergency vehicle demand,and this type of vehicle is immediately charged in fast charging mode after connecting to the grid.On the contrary,it is a non-emergency demand,and the vehicle is connected to the grid to choose the appropriate time to charge in conventional charging mode.Finally,by optimizing the objective function to minimize the peakto-valley difference between the grid and the vehicle owner’s charging cost,and designing the charging continuity constraints to avoid battery damage,it ensures that the vehicle is efficiently dispatched under the premise of meeting the minimum power demand.Simulation results show that the proposed charging strategy can reduce the charging cost of vehicle owners by 26.33%,reduce the peak-to-valley difference rate of the grid by 29.8%,and significantly alleviate the congestion problem during peak load hours,compared with the disordered charging mode,while ensuring that the electric vehicles are not overcharged and meet the electricity demand of vehicle owners.This paper solves the problems of the existing research on the singularity of vehicle models and the lack of environmental adaptability and provides both economic and practical solutions for the cooperative optimization of electric vehicles and power grids in multiple scenarios.
基金the National Natural Science Foundation of China(NSFC)(52076213)the 2115 Talent Development Program of China Agricultural University for the financial coverage of this work。
文摘High-power direct current fast charging(DC-HPC),particularly for megawatt-level charging currents(≥1000 A),is expected to significantly reduce charging time and improve electric vehicle durability,despite the risk of instantaneous thermal shocks.Conventional cooling methods,which separately transmit current and heat,struggle to achieve both flexible maneuverability and high-efficiency cooling.In this study,we present a synergetic cooling and transmission strategy using a gallium-based liquid metal flexible charging connector(LMFCC),which efficiently dissipates ultra-high heat flux while simultaneously carrying superhigh current.The LMFCC exhibits exceptional flexible operability(bending radius of 2 cm)and transmission stability even under significant deformation owing to the excellent liquidity and conductivity of liquid metal(LM).These properties are markedly better than those of solid metal connector.A compact induction electromagnet-driven method is optimized to significantly increase the LM flow rate and the active cooling capacity,resulting in sudden low temperature(<16℃at 1000 A).This synergetic cooling and charging strategy are expected to enable ultrahigh-heat-flux thermal management and accelerate development of the electric vehicle industry.
基金The National Natural Science Foundation of China under Grant Nos.11864006,11874309,12164007,and 12204118。
文摘In this work,Langevin dynamics simulations were carried out to thoroughly investigate the swapping process of composite knots under tension in a cuboid nanochannel.From our analysis,the free energy profiles of knot swapping under different conditions were extracted from the overall probability distribution of the relative distance between the centers of composite knots.In addition,the impact of the stretching force,confinement size,and bending stiffness on the free energy profiles was directly identified.Especially,the influence of topology structure is for the first time reported.The increasing stretching force in a fixed confinement or the confinement size under a constant stretching force does not alter their respective equilibrium populations at the separate state and the entangled state.In contrast,a bending stiffness larger than 15 enhanced the formation of the entangled state.The topology structure of the 51knot,which was different from the 52knot,resulted in forming a metastable state in the free energy profiles.The increasing stretching forces yielded an enhancement of the following free energy barrier.
文摘Harnessing the potential of graphite is key to fast charging at 4C(fully charged within 15 minutes)for electric vehicles.However,graphite is subject to lithium dendrite growth during charging,leading to short circuits and battery failures,which is one of the biggest problems for batteries[1-4].Therefore,quickly identifying the lithium dendrites and different types of dendrites on the graphite surface can quickly help analyze the state of graphite and design good charging protocols.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(RS-2023-00242528,50%)supported by a grant from the Korea Electric Power Corporation(R24XO01-4,50%)for basic research and development projects starting in 2024.
文摘The accelerated global adoption of electric vehicles(EVs)is driving significant expansion and increasing complexity within the EV charging infrastructure,consequently presenting novel and pressing cybersecurity challenges.While considerable effort has focused on preventative cybersecurity measures,a critical deficiency persists in structured methodologies for digital forensic analysis following security incidents,a gap exacerbated by system heterogeneity,distributed digital evidence,and inconsistent logging practices which hinder effective incident reconstruction and attribution.This paper addresses this critical need by proposing a novel,data-driven forensic framework tailored to the EV charging infrastructure,focusing on the systematic identification,classification,and correlation of diverse digital evidence across its physical,network,and application layers.Our methodology integrates open-source intelligence(OSINT)with advanced system modeling based on a three-layer cyber-physical system architecture to comprehensively map potential evidentiary sources.Key contributions include a comprehensive taxonomy of cybersecurity threats pertinent to EV charging ecosystems,detailed mappings between these threats and the resultant digital evidence to guide targeted investigations,the formulation of adaptable forensic investigation workflows for various incident scenarios,and a critical analysis of significant gaps in digital evidence availability within current EV charging systems,highlighting limitations in forensic readiness.The practical application and utility of this method are demonstrated through illustrative case studies involving both empirically-derived and virtual incident scenarios.The proposed datadriven approach is designed to significantly enhance digital forensic capabilities,support more effective incident response,strengthen compliance with emerging cybersecurity regulations,and ultimately contribute to bolstering the overall security,resilience,and trustworthiness of this increasingly vital critical infrastructure.
基金supported by National Natural Science Foundation of China(No.62073212)Shanghai Science and Technology Commission(No.23ZR1426600).
文摘Automated guided vehicles(AGVs)are key equipment in automated container terminals(ACTs),and their operational efficiency can be impacted by conflicts and battery swapping.Additionally,AGVs have bidirectional transportation capabilities,allowing them tomove in the opposite directionwithout turning around,which helps reduce transportation time.This paper aims at the problem of AGV scheduling and bidirectional conflict-free routing with battery swapping in automated terminals.A bi-level mixed integer programming(MIP)model is proposed,taking into account task assignment,bidirectional conflict-free routing,and battery swapping.The upper model focuses on container task assignment and AGV battery swapping planning,while the lower model ensures conflict-free movement of AGVs.A double-threshold battery swapping strategy is introduced,allowing AGVs to utilize waiting time for loading for battery swapping.An improved differential evolution variable neighborhood search(IDE-VNS)algorithm is developed to solve the bi-level MIP model,aiming to minimize the completion time of all jobs.Experimental results demonstrate that compared to the differential evolution(DE)algorithm and the genetic algorithm(GA),the IDEVNS algorithmreduces fitness values by 44.49% and 45.22%,though it does increase computation time by 56.28% and 62.03%,respectively.Bidirectional transportation reduces the fitness value by an average of 10.97% when the container scale is small.As the container scale increases,the fitness value of bidirectional transportation gradually approaches that of unidirectional transportation.The results further show that the double-threshold battery swapping strategy enhances AGV utilization and reduces the fitness value.
基金supported by the National Natural Science Foundation of China(No.52002170)the Central Guidance Fund Project for Local Scientific and Technological Development in Qinghai Province(No.2024ZY013)+1 种基金the Foundation of Key Laboratory of Flexible Electronics of Zhejiang Province(No.2023FE011)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX24_1635).
文摘Developing fast-charging lithium-ion batteries(LIBs)that feature high energy density is critical for the scalable application of electric vehicles.Iron vanadate(FVO)holds great potential as anode material in fast-charging LIBs because of its high theoretical specific capacity and the high natural abundance of its constituents.However,the capacity of FVO rapidly decays due to its low electrical conductivity.Herein,uniform FVO nanoparticles are grown in situ on ordered mesoporous carbon(CMK-3)support,forming a highly electrically conductive porous network,FVO/CMK-3.The structure of CMK-3 helps prevent agglomeration of FVO particles.The electrically conductive nature of CMK-3 can further enhance the electrical conductivity of FVO/CMK-3 and buffer the volume expansion of FVO particles during cycling processes.As a result,the FVO/CMK-3 displays excellent fast-charging performance of 364.6 mAh·g^(-1)capacity for 2500 cycles at 10 A·g^(-1)(with an ultralow average capacity loss per cycle of 0.003%)through a pseudocapacitive-dominant process.Moreover,the LiCoO_(2)//FVO/CMK-3 full cell achieves a high capacity of 100.2 mAh·g^(-1)and a high capacity retention(96.2%)after 200 cycles.The superior electrochemical performance demonstrates that FVO/CMK-3 is an ideal anode material candidate for fast-charging,stable LIBs with high energy density.
文摘The global public HPC(high-power charging)network for EVs(electric vehicles)is rapidly expanding.This growth is crucial for supporting the increasing adoption of EVs but highlights the industry’s early stage.Regional maturity varies,with China leading due to strong government support,followed by Europe and the United States.A significant challenge is the lack of industry standards,causing inconsistencies in charger types and payment systems.Efforts are underway,to ensure interoperability and reliability.Interoperability is crucial for the success of EV HPC infrastructure,ensuring seamless integration among charge points,management systems,and service providers.Despite the use of protocols like the OCPP(Open Charge Point Protocol),variations in implementation create complexities.Ensuring uniform standards across the ecosystem is essential for reliability and efficiency.Vendor-specific error codes,which are more detailed than standardized codes,are vital for diagnosing issues but lack standardization,adding complexity.Addressing these challenges is key to supporting widespread EV adoption and enhancing user experience.To provide a compelling driver value proposition,EV charging services must be reliable and seamless.The operations and maintenance of the HPC network must be cost-effective and leverage the intelligence of the integrated ecosystem.The technical complexity of managing high-power DC charging,combined with diverse authentication and payment systems,results in numerous potential issues.Moving from reactive to predictive maintenance is essential for undisrupted operations and a smooth driver experience.Shell’s Intelligent Operations Technology Strategy incorporates GenAI elements in its advanced analytics and operational performance management tools.By ingesting big data from multiple sources across the EV ecosystem,Shell engineers can perform detailed pattern recognition and targeted troubleshooting.Monitoring,configurable alerting,and remote fixing based on auto-healing and targeted auto-allocation enhance charger availability and reduce downtime.This automation has evolved Shell’s maintenance and operations strategy from reactive to predictive,improving overall charger performance and user satisfaction.Key achievements include transitioning to prescriptive and preventive asset management approaches,significantly improving uptime and charging experience,and increasing commercial value through cost reduction and enhanced revenue.Future challenges include evolving OCPP,integrating data from non-OCPP systems,and ensuring interoperability across diverse systems.Standardization and cross-collaboration within the industry are essential for smooth interoperability,higher uptime,and increased CSR(charging success rate).Technological innovations will further shape the industry,promoting stabilization and efficiency as it matures.
基金supported by the Shenzhen Science and Technology Program(SGDX20230821100459001)the YCRG-CRF(C1002-24Y)the GRF Project(CityU 11220322,CityU 7006015),the City University of Hong Kong,Shenzhen Research Institute。
文摘Ni-rich cathode materials are essential for enhancing the performance of lithium-ion batteries(LIBs)in electric vehicles(EVs),particularly concerning extreme fast charging(XFC)and durability.While much of studies shine a spotlight on Li plating on the anode to improve rate capability,there is a critical lack of studies addressing the combination of kinetic improvements and mechanical strength of cathode materials under XFC conditions.In this work,Mg/Ti co-doped Ni-rich LiNi_(0.88)Co_(0.09)Mn_(0.03)O_(2)(MT-NCM)was successfully synthesized to address structural challenges associated with high-rate cycling.The results demonstrate that the stronger Ti–O bond contributes to the enhanced mechanical strength of secondary grains,which effectively alleviates microcrack formation during fast charging.Additionally,the detrimental phase transitions and internal strain as well as parasitic reactions of MT-NCM are significantly suppressed due to the synergistic effect of the dual dopants,ensuring excellent Li-ion transport kinetics compared to pristine NCM(P-NCM).Consequently,MT-NCM achieves remarkable high-rate cycling performance,retaining 88.04%of its initial capacity at 5 C and superior discharge capacity over 175 mA h g^(−1)even at 10 C.This work highlights the potential of optimizing the kinetic-mechanical properties of Ni-rich cathodes,providing a viable approach for the development of XFC LIBs with improved durability for EV applications.
基金financially supported by the National Natural Science Foundation of China(Grant No.52202328,52372099)the Shanghai Sailing Program(22YF1455500).
文摘Poor Li plating reversibility and high thermal runaway risks are key challenges for fast charging lithiumion batteries with graphite anodes.Herein,a dielectric and fire-resistant separator based on hybrid nanofibers of barium sulfate(BS)and bacterial cellulose(BC)is developed to synchronously enhance the battery's fast charging and thermal-safety performances.The regulation mechanism of the dielectric BS/BC separator in enhancing the Li^(+)ion transport and Li plating reversibility is revealed.(1)The Max-Wagner polarization electric field of the dielectric BS/BC separator can accelerate the desolvation of solvated Li^(+)ions,enhancing their transport kinetics.(2)Moreover,due to the charge balancing effect,the dielectric BS/BC separator homogenizes the electric field/Li^(+)ion flux at the graphite anode-separator interface,facilitating uniform Li plating and suppressing Li dendrite growth.Consequently,the fast-charge graphite anode with the BS/BC separator shows higher Coulombic efficiency(99.0%vs.96.9%)and longer cycling lifespan(100 cycles vs.59 cycles)than that with the polypropylene(PP)separator in the constantlithiation cycling test at 2 mA cm^(-2).The high-loading LiFePO4(15.5 mg cm^(-2))//graphite(7.5 mg cm^(-2))full cell with the BS/BC separator exhibits excellent fast charging performance,retaining 70%of its capacity after 500 cycles at a high rate of 2C,which is significantly better than that of the cell with the PP separator(retaining only 27%of its capacity after 500 cycles).More importantly,the thermally stable BS/BC separator effectively elevates the critical temperature and reduces the heat release rate during thermal runaway,thereby significantly enhancing the battery's safety.
基金supported by the Lithium Resources and Lithium Materials Key Laboratory of Sichuan Province(LRMKF202405)the National Natural Science Foundation of China(52402226)+3 种基金the Natural Science Foundation of Sichuan Province(2024NSFSC1016)the Scientific Research Startup Foundation of Chengdu University of Technology(10912-KYQD2023-10240)the opening funding from Key Laboratory of Engineering Dielectrics and Its Application(Harbin University of Science and Technology)(KFM202507,Ministry of Education)the funding provided by the Alexander von Humboldt Foundation。
文摘The properties of electrolytes are critical for fast-charging and stable-cycling applications in lithium metal batteries(LMBs).However,the slow kinetics of Li^(+)transport and desolvation in commercial carbonate electrolytes,cou pled with the formation of unstable solid electrolyte interphases(SEI),exacerbate the degradation of LMB performance at high current densities.Herein,we propose a versatile electrolyte design strategy that incorporates cyclohexyl methyl ether(CME)as a co-solvent to reshape the Li^(+)solvation environment by the steric-hindrance effect of bulky molecules and their competitive coordination with other solvent molecules.Simulation calculations and spectral analysis demonstrate that the addition of CME molecules reduces the involvement of other solvent molecules in the Li solvation sheath and promotes the formation of Li^(+)-PF_(6)^(-)coordination,thereby accelerating Li^(+)transport kinetics.Additionally,this electrolyte composition improves Li^(+)desolvation kinetics and fosters the formation of inorganic-rich SEI,ensuring cycle stability under fast charging.Consequently,the Li‖LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)battery with the modified electrolyte retains 82% of its initial capacity after 463 cycles at 1 C.Even under the extreme fast-charging condition of 5 C,the battery can maintain 80% capacity retention after 173 cycles.This work provides a promising approach for the development of highperformance LMBs by modulating solvation environment of electrolytes.
基金supported by the New Energy Vehicle Power Battery Life Cycle Testing and Verification Public Service Platform Project(No.2022-235-224).
文摘High-nickel ternary silicon-carbon lithium-ion batteries,which use silicon-carbon materials as anodes and high-nickel ternary materials as cathodes,have already been commercialized as power batteries.The increasing demand for high-energy density and rapid charging characteristics has heightened the urgency of improving their fast charging cycle performance while establishing degradation mechanisms.Based on a pouch battery design with an energy density of 285 Wh·kg^(-1),this work studied 3 Ah pouch batteries for fast charging cycles ranging from 0.5C to 3C.Non-destructive techniques,such as differential voltage,incremental capacity analysis,and electrochemical impedance spectroscopy,were employed to investigate the effects of charging rates on battery cycling performance and to establish the degradation mechanisms.The experimental results indicated that capacity diving was observed at all charging rates.However,at lower rates(0.5C-2C),more cycles were achieved,while at higher rates(2C-3C),the cycle life remained relatively stable.Computed tomography,electrochemical performance analysis,and physicochemical characterizations were obtained,using scanning electron microscopy with energy dispersive spectroscopy,X-ray diffraction,X-ray photoelectron spectroscopy,and inductively coupled plasma optical emission spectrometry.The mechanisms of capacity decrease during 3C fast charging cycles were investigated.It is proposed that the primary causes of capacity diving during 3C fast charging are the degradation of SiOx,anode polarization,and the simultaneous dissolution of metal ions in the cathode which were deposited at the anode,resulting the continuous growth and remodeling of the SEI membrane at the anode,thereby promoting more serious side reactions.
基金funded by the Key Research and Development Program of Shandong Province(2023CXPT069)Opening Funds of the State Key Laboratory of Building Safety and Built Environment(BSBE2022-EET-06)Innovation Project of Guangwei Group Academician Workstation(GWYS-2022-04)。
文摘Sodium metal batteries(SMBs)are promising candidates for next-generation energy storage devices owing to their excellent safety performance and natural abunda nce of sodium.However,the insurmountable obstacles of dendrite formation and quick capacity decay are caused by an unstable and inhomogeneous solid electrolyte interphase that resulted from the immediate interactions between the Na metal anode and organic liquid electrolyte.Herein,a customised glass fibre separator coupled with chitosan(CS@GF)was developed to modulate the sodium ion(Na^(+))flux.The CS@GF separator facilitates the Na+homogeneous deposition on the anode side through redistribution at the chitosan polyactive sites and by inhibiting the decomposition of the electrolyte to robust solid electrolyte interphase(SEI)formation.Multiphysics simulations show that chitosan incorporated into SMBs through the separator can make the local electric field around the anode uniform,thus facilitating the transfer of cations.Na|Na symmetric cells utilising a CS@GF separator exhibited an outstanding cycle stability of over 600 h(0.5 mA cm^(-2)).Meanwhile,the Na|Na_(3)V_(5)(PO_(4))_(3)full cell exhibited excellent fast-charging performance(93.47%capacity retention after 1500 cycles at 5C).This study presents a promising strategy for inhibiting dendrite growth and realizes stable Na metal batteries,which significantly boosts the development of high-performance SMBs.
文摘Electric vehicles are pivotal in the global shift toward decarbonizing road transport,with lithium-ion batteries at the heart of this technological evolution.However,the pursuit of batteries capable of extremely fast charging that also satisfy high energy and safety criteria,poses a significant challenge to current lithium-ion batteries technologies.Additionally,the increasing demand for aluminum(Al)and copper(Cu)in electrification,solar energy technologies,and vehicle light-eighting is driving these metals toward near-critical status in the medium term.This study introduces metalized polythylene terephthalate(mPET)polymer films by depositing an Al or Cu thin layer onto two sides of a polyethylene terephthalate film—named mPET/Al and mPET/Cu,as lightweight,cost-effective alternatives to traditional metal current collectors in lithium-ion batteries.We have fabricated current collectors that significantly reduce weight(by 73%),thickness(by 33%),and cost(by 85%)compared with traditional metal foil counterparts.These advancements have the potential to enhance energy density to 280 Wh kg^(-1) at the electrode level under 10-min charging at 6 C.Through testing,including a novel extremely fast charging protocol across various C-rates and long-term cycling(up to 1000 cycles)in different cell configurations,the superior performance of these metalized polymer films has been demonstrated.Notably,mPET/Cu and mPET/Al films exhibited comparable capacities to conventional cells under extremely fast charging,with the mPET cells showing a 27%improvement in energy density at 6 C and maintaining significant energy density after 1000 cycles.This study underscores the potential of mPET films to revolutionize the roll-to-roll battery manufacturing process and significantly advance the performance metrics of lithium-ion batteries in electric vehicles applications.
文摘Electric Vehicle Charging Systems(EVCS)are increasingly vulnerable to cybersecurity threats as they integrate deeply into smart grids and Internet ofThings(IoT)environments,raising significant security challenges.Most existing research primarily emphasizes network-level anomaly detection,leaving critical vulnerabilities at the host level underexplored.This study introduces a novel forensic analysis framework leveraging host-level data,including system logs,kernel events,and Hardware Performance Counters(HPC),to detect and analyze sophisticated cyberattacks such as cryptojacking,Denial-of-Service(DoS),and reconnaissance activities targeting EVCS.Using comprehensive forensic analysis and machine learning models,the proposed framework significantly outperforms existing methods,achieving an accuracy of 98.81%.The findings offer insights into distinct behavioral signatures associated with specific cyber threats,enabling improved cybersecurity strategies and actionable recommendations for robust EVCS infrastructure protection.
