The cluster DC voltage balancing control adopting zero-sequence voltage injection is appropriate for the starconnected cascaded H-bridge STATCOM because no zerosequence currents are generated in the three-phase three-...The cluster DC voltage balancing control adopting zero-sequence voltage injection is appropriate for the starconnected cascaded H-bridge STATCOM because no zerosequence currents are generated in the three-phase three-wire system.However,as the zero-sequence voltage is expressed in trigonometric form,traditional control methods involve many complicated operations,such as the square-root,trigonometric operations,and inverse tangent operations.To simplify cluster voltage balancing control,this paper converts the zero-sequence voltage to the dq frame in a DC representation by introducing a virtually orthogonal variable,and the DC components of the zero-sequence voltage in the dq frame are regulated linearly by proportional integral regulators,rather than being calculated from uneven active powers in traditional controls.This removes all complicated operations.Finally,this paper presents simulation and experimental results for a 400 V±7.5 kvar star-connected STATCOM,in balanced and unbalanced scenarios,thereby verifying the effectiveness of the proposed control.展开更多
Metal-insulator-metal aluminium electrolytic capacitors(MIM-AECs)combine high capacity-density and high breakdown field strength of solid AECs with high-frequency responsibility,wide workingtemperature window and wate...Metal-insulator-metal aluminium electrolytic capacitors(MIM-AECs)combine high capacity-density and high breakdown field strength of solid AECs with high-frequency responsibility,wide workingtemperature window and waterproof properties of MIM nanocapacitors.However,interfacial atomic diffusion poses a major obstacle,preventing the high-voltage MIM-AECs exploitation and thereby hampering their potential and advantages in high-power and high-energy-density applications.Here,an innovative high-voltage MIM-AECs were fabricated.The AlPO_(4)buffer layer is formed on AlO(OH)/AAO/Al surface by using H_(3)PO_(4)treatment,then a stable van der Waals(vdW)SnO_(2)/AlPO_(4)/AAO/Al multilayer was constructed via atomic layer deposition(ALD)technology.Due to higher diffusion barrier and lower carrier migration of SnO_(2)/AlPO_(4)/AAO interfaces,Sn atom diffusion is inhibited and carrier acceleration by electric field is weakened,guaranteeing high breakdown field strength of dielectric AAO and avoiding local breakdown risks.Through partial etching to hydrated AlO(OH)by H_(3)PO_(4)treatment,the tunnel was further opened up to facilitate subsequent ALD-SnO_(2)entry,thus obtaining a high SnO_(2)coverage.The SnO_(2)/AlPO_(4)/AAO/Al capacitors show a comprehensive performance in high-voltage(260 V),hightemperature(335℃),high-humidity(100%RH)and high-frequency response(100 k Hz),outperforming commercial solid-state AECs,and high-energy density(8.6μWh/cm^(2)),markedly exceeding previously reported MIM capacitors.The work lays the foundation for next-generation capacitors with highvoltage,high-frequency,high-temperature and high-humidity resistance.展开更多
Fluoride-based electrolyte exhibits extraordinarily high oxidative stability in high-voltage lithium metal batteries(h-LMBs) due to the inherent low highest occupied molecular orbital(HOMO) of fiuorinated solvents. Ho...Fluoride-based electrolyte exhibits extraordinarily high oxidative stability in high-voltage lithium metal batteries(h-LMBs) due to the inherent low highest occupied molecular orbital(HOMO) of fiuorinated solvents. However, such fascinating properties do not bring long-term cyclability of h-LMBs. One of critical challenges is the interface instability in contacting with the Li metal anode, as fiuorinated solvents are highly susceptible to exceptionally reductive metallic Li attributed to its low lowest unoccupied molecular orbital(LUMO), which leads to significant consumption of the fiuorinated components upon cycling.Herein, attenuating reductive decomposition of fiuorinated electrolytes is proposed to circumvent rapid electrolyte consumption. Specifically, the vinylene carbonate(VC) is selected to tame the reduction decomposition by preferentially forming protective layer on the Li anode. This work, experimentally and computationally, demonstrates the importance of pre-passivation of Li metal anodes at high voltage to attenuate the decomposition of fiuoroethylene carbonate(FEC). It is expected to enrich the understanding of how VC attenuate the reactivity of FEC, thereby extending the cycle life of fiuorinated electrolytes in high-voltage Li-metal batteries.展开更多
Sodium-ion batteries hold great promise as next-generation energy storage systems.However,the high instability of the electrode/electrolyte interphase during cycling has seriously hindered the development of SIBs.In p...Sodium-ion batteries hold great promise as next-generation energy storage systems.However,the high instability of the electrode/electrolyte interphase during cycling has seriously hindered the development of SIBs.In particular,an unstable cathode–electrolyte interphase(CEI)leads to successive electrolyte side reactions,transition metal leaching and rapid capacity decay,which tends to be exacerbated under high-voltage conditions.Therefore,constructing dense and stable CEIs are crucial for high-performance SIBs.This work reports localized high-concentration electrolyte by incorporating a highly oxidation-resistant sulfolane solvent with non-solvent diluent 1H,1H,5H-octafluoropentyl-1,1,2,2-tetrafluoroethyl ether,which exhibited excellent oxidative stability and was able to form thin,dense and homogeneous CEI.The excellent CEI enabled the O3-type layered oxide cathode NaNi_(1/3)Mn_(1/3)Fe_(1/3)O_(2)(NaNMF)to achieve stable cycling,with a capacity retention of 79.48%after 300 cycles at 1 C and 81.15%after 400 cycles at 2 C with a high charging voltage of 4.2 V.In addition,its nonflammable nature enhances the safety of SIBs.This work provides a viable pathway for the application of sulfolane-based electrolytes on SIBs and the design of next-generation high-voltage electrolytes.展开更多
Fluctuating voltage levels in power grids necessitate automatic voltage regulators(AVRs)to ensure stability.This study examined the modeling and control of AVR in hydroelectric power plants using model predictive cont...Fluctuating voltage levels in power grids necessitate automatic voltage regulators(AVRs)to ensure stability.This study examined the modeling and control of AVR in hydroelectric power plants using model predictive control(MPC),which utilizes an extensive mathe-matical model of the voltage regulation system to optimize the control actions over a defined prediction horizon.This predictive feature enables MPC to minimize voltage deviations while accounting for operational constraints,thereby improving stability and performance under dynamic conditions.Thefindings were compared with those derived from an optimal proportional integral derivative(PID)con-troller designed using the artificial bee colony(ABC)algorithm.Although the ABC-PID method adjusts the PID parameters based on historical data,it may be difficult to adapt to real-time changes in system dynamics under constraints.Comprehensive simulations assessed both frameworks,emphasizing performance metrics such as disturbance rejection,response to load changes,and resilience to uncertainties.The results show that both MPC and ABC-PID methods effectively achieved accurate voltage regulation;however,MPC excelled in controlling overshoot and settling time—recording 0.0%and 0.25 s,respectively.This demonstrates greater robustness compared to conventional control methods that optimize PID parameters based on performance criteria derived from actual system behavior,which exhibited settling times and overshoots exceeding 0.41 s and 5.0%,respectively.The controllers were implemented using MATLAB/Simulink software,indicating a significant advancement for power plant engineers pursuing state-of-the-art automatic voltage regulations.展开更多
The high proportion of uncertain distributed power sources and the access to large-scale random electric vehicle(EV)charging resources further aggravate the voltage fluctuation of the distribution network,and the exis...The high proportion of uncertain distributed power sources and the access to large-scale random electric vehicle(EV)charging resources further aggravate the voltage fluctuation of the distribution network,and the existing research has not deeply explored the EV active-reactive synergistic regulating characteristics,and failed to realize themulti-timescale synergistic control with other regulatingmeans,For this reason,this paper proposes amultilevel linkage coordinated optimization strategy to reduce the voltage deviation of the distribution network.Firstly,a capacitor bank reactive power compensation voltage control model and a distributed photovoltaic(PV)activereactive power regulationmodel are established.Additionally,an external characteristicmodel of EVactive-reactive power regulation is developed considering the four-quadrant operational characteristics of the EVcharger.Amultiobjective optimization model of the distribution network is then constructed considering the time-series coupling constraints of multiple types of voltage regulators.A multi-timescale control strategy is proposed by considering the impact of voltage regulators on active-reactive EV energy consumption and PV energy consumption.Then,a four-stage voltage control optimization strategy is proposed for various types of voltage regulators with multiple time scales.Themulti-objective optimization is solved with the improvedDrosophila algorithmto realize the power fluctuation control of the distribution network and themulti-stage voltage control optimization.Simulation results validate that the proposed voltage control optimization strategy achieves the coordinated control of decentralized voltage control resources in the distribution network.It effectively reduces the voltage deviation of the distribution network while ensuring the energy demand of EV users and enhancing the stability and economic efficiency of the distribution network.展开更多
Capacitive voltage transformers (CVTs) are essential in high-voltage systems. An accurate error assessment is crucial for precise energy metering. However, tracking real-time quantitative changes in capacitive voltage...Capacitive voltage transformers (CVTs) are essential in high-voltage systems. An accurate error assessment is crucial for precise energy metering. However, tracking real-time quantitative changes in capacitive voltage transformer errors, particularly minor variations in multi-channel setups, remains challenging. This paper proposes a method for online error tracking of multi-channel capacitive voltage transformers using a Co-Prediction Matrix. The approach leverages the strong correlation between in-phase channels, particularly the invariance of the signal proportions among them. By establishing a co-prediction matrix based on these proportional relationships, The influence of voltage changes on the primary measurements is mitigated. Analyzing the relationships between the co-prediction matrices over time allows for inferring true measurement errors. Experimental validation with real-world data confirms the effectiveness of the method, demonstrating its capability to continuously track capacitive voltage transformer measurement errors online with precision over extended durations.展开更多
This study examines the influence of magnetic field and temperature on the transient voltage of a polycrystalline silicon radial junction solar cell in a dynamic regime under multispectral illumination. Radial junctio...This study examines the influence of magnetic field and temperature on the transient voltage of a polycrystalline silicon radial junction solar cell in a dynamic regime under multispectral illumination. Radial junction solar cells represent a major advancement in photovoltaic technologies, as they optimize light absorption and charge collection efficiency. The focus is on the impact of the magnetic field and temperature on the decay of transient voltage, which provides crucial information on recombination processes and the lifetime of minority carriers. The results reveal that the magnetic field tends to increase the transient voltage by directly affecting the transient electron density. Indeed, for B > 7 × 10−5 T, the magnetic field prolongs the relaxation time by increasing the transient voltage amplitude. Additionally, rising temperatures accelerate (ranging from 290 K to 450 K) recombination processes, thereby reducing the transient voltage, although this effect is moderated by the presence of a magnetic field. The study highlights the complex interaction between magnetic field and temperature, with significant impacts on the transient behaviour.展开更多
With the rapid integration of renewable energy sources,modern power systems are increasingly challenged by heightened volatility and uncertainty.Doubly-fed variable-speed pumped storage units(DFVS-PSUs)have emerged as...With the rapid integration of renewable energy sources,modern power systems are increasingly challenged by heightened volatility and uncertainty.Doubly-fed variable-speed pumped storage units(DFVS-PSUs)have emerged as promising technologies for mitigating grid oscillations and enhancing system flexibility.However,the excitation converters in DFVS-PSUs are prone to significant issues such as elevated common-mode voltage(CMV)and neutral-point voltage(NPV)fluctuations,which can lead to electromagnetic interference and degrade transient performance.To address these challenges,an optimized virtual space vector pulse width modulation(OVSVPWM)strategy is proposed,aiming to suppress CMV and NPV simultaneously through coordinated multi-objective control.Specifically,a dynamic feedback mechanism is introduced to adjust the balancing factor of basic vectors in the synthesized virtual small vector in real-time,achieving autonomous balancing of the NPV.To address the excessive switching actions introduced by the OVSVPWM strategy,a phase duty ratio-based sequence reconstruction method is adopted,which reduces the total number of switching actions to half of the original.A zero-level buffering scheme is employed to reconstruct the single-phase voltage-level output sequence,achieving peak CMV suppression down to udc/6.Simulation results demonstrate that the proposed strategy significantly improves electromagnetic compatibility and operational stability while maintaining high power quality.展开更多
This paper explores the impact of back-gate bias (V_(soi)) and supply voltage (V_(DD)) on the single-event upset (SEU) cross section of 0.18μm configurable silicon-on-insulator static random-access memory (SRAM) unde...This paper explores the impact of back-gate bias (V_(soi)) and supply voltage (V_(DD)) on the single-event upset (SEU) cross section of 0.18μm configurable silicon-on-insulator static random-access memory (SRAM) under high linear energy transfer heavyion experimentation.The experimental findings demonstrate that applying a negative back-gate bias to NMOS and a positive back-gate bias to PMOS enhances the SEU resistance of SRAM.Specifically,as the back-gate bias for N-type transistors(V_(nsoi)) decreases from 0 to-10 V,the SEU cross section decreases by 93.23%,whereas an increase in the back-gate bias for P-type transistors (V_(psoi)) from 0 to 10 V correlates with an 83.7%reduction in SEU cross section.Furthermore,a significant increase in the SEU cross section was observed with increase in supply voltage,as evidenced by a 159%surge at V_(DD)=1.98 V compared with the nominal voltage of 1.8 V.To explore the physical mechanisms underlying these experimental data,we analyzed the dependence of the critical charge of the circuit and the collected charge on the bias voltage by simulating SEUs using technology computer-aided design.展开更多
In this paper, we proposed an output voltage stabilization of a DC-DC Zeta converter using hybrid control. We modeled the Zeta converter under continuous conduction mode operation. We derived a switching control law t...In this paper, we proposed an output voltage stabilization of a DC-DC Zeta converter using hybrid control. We modeled the Zeta converter under continuous conduction mode operation. We derived a switching control law that brings the output voltage to the desired level. Due to infinite switching occurring at the desired level, we enhanced the switching control law by allowing a sizeable output voltage ripple. We derived mathematical models that allow one to choose the desired switching frequency. In practice, the existence of the non-ideal properties of the Zeta converter results in steady-state output voltage error. By analyzing the power loss in the zeta converter, we proposed an improved switching control law that eliminates the steady-state output voltage error. The effectiveness of the proposed method is illustrated with simulation results.展开更多
The active equalization of lithium-ion batteries involves transferring energy from high-voltage cells to low-voltage cells,ensuring consistent voltage levels across the battery pack and maintaining safety.This paper p...The active equalization of lithium-ion batteries involves transferring energy from high-voltage cells to low-voltage cells,ensuring consistent voltage levels across the battery pack and maintaining safety.This paper presents a voltage balancing circuit and control method.First,a single capacitor method is used to design the circuit topology for energy transfer.Next,real-time voltage detection and control are employed to balance energy between cells.Finally,simulation and experimental results demonstrate the effectiveness of the proposed method,achieving balanced voltages of 3.97 V from initial voltages of 4.10,3.97,and 3.90 V.The proposed circuit is simple,reliable,and effectively prevents overcharge and overdischarge.展开更多
Voltage substrate mapping is a promising tool for the treatment of atrial fibrillation(AF).It is helpful to detect atrial fibrosis,which includes areas with low bipolar voltage,heterogeneous conduction properties,and ...Voltage substrate mapping is a promising tool for the treatment of atrial fibrillation(AF).It is helpful to detect atrial fibrosis,which includes areas with low bipolar voltage,heterogeneous conduction properties,and shortened effective refractory period.The voltage amplitude is typically defined as the maximal peakto-peak level within a specified time window of interest.Contemporary electroanatomic mapping platforms now enable many thousands of data points to be mapped,so that a geometric model of the atrial endocardium is constructable over a short period of time.This mapping procedure is often done with bipolar electrodes to cancel the far-field signal.The recording site coordinates are projected onto an atrial shell,with interpolation of the voltage data across the shell surface.The amplitude of the recorded bipolar electrogram depicted on the threedimensional shell provides detailed information for substrate mapping.Wherever there are areas of low peak-to-peak voltage,it is thought to mark the presence of abnormal tissue properties and conduction.However,uncontrolled variables and environmental factors affecting voltage level include the oncoming electrical activation wavefront direction,the catheter incidence angle,the force applied to the catheter,and the region-variable shape and structure of atrial tissue.Techniques and settings to acquire atrial voltage data for AF analysis have not been standardized.Methods to characterize atrial electrograms are also presently limited.These factors affect quality and reproducibility of the mapping results.Herein,voltage substrate mapping and its variables pertaining to AF and radiofrequency ablation are described and discussed,with suggestions for future work efforts.展开更多
Efficient battery charging requires a power conversion system capable of providing precise voltage regulation tailored to the battery’s needs.This study develops a buck converter with a 36 V input for charging a 14 V...Efficient battery charging requires a power conversion system capable of providing precise voltage regulation tailored to the battery’s needs.This study develops a buck converter with a 36 V input for charging a 14 V battery using the Constant Voltage(CV)method.The system is designed to ensure safe and efficient charging while protecting the battery from overcharging and extending its lifespan.In the proposed design,the converter maintains a constant output voltage while the charging current decreases as the battery approaches full capacity.Pulse Width Modulation(PWM)is used as a control strategy to modify the duty cycle of the converter.This keeps the voltage output stable whenever the load changes.The design process involves simulation and experimental validation to evaluate the system’s performance and efficiency.The test results show the significant impact of Proportional-Integral-Derivative(PID)control on the stability of the output voltage to meet the requirements for 14 V battery charging and the efficiency of the battery charging process.The output voltage becomes more stable,with reduced oscillation and minimal steadystate error.The State of Charge(SOC)increases more stably,controllably,and efficiently thanks to the PID controller’s ability to adjust the duty cycle in real time based on system feedback.This dynamic adjustment ensures that the output current and voltage remain within the optimal range,which directly improves the battery charging process.In addition,PID control significantly improves the dynamic response of the system,reducing overshoot and settling time while maintaining precise voltage regulation.This speeds up the battery charging process and contributes to better energy efficiency,reduced power loss,and extended battery life.This research provides a reliable and cost-effective solution for applications in electric vehicles,renewable energy systems,and other battery-powered devices.展开更多
This paper deeply introduces a brand-new research method for the synchronous characteristics of DC microgrid bus voltage and an improved synchronous control strategy.This method mainly targets the problem of bus volta...This paper deeply introduces a brand-new research method for the synchronous characteristics of DC microgrid bus voltage and an improved synchronous control strategy.This method mainly targets the problem of bus voltage oscillation caused by the bifurcation behavior of DC microgrid converters.Firstly,the article elaborately establishes a mathematical model of a single distributed power source with hierarchical control.On this basis,a smallworld network model that can better adapt to the topology structure of DC microgrids is further constructed.Then,a voltage synchronization analysis method based on the main stability function is proposed,and the synchronous characteristics of DC bus voltage are deeply studied by analyzing the size of the minimum non-zero eigenvalue.In view of the situation that the line coupling strength between distributed power sources is insufficient to achieve bus voltage synchronization,this paper innovatively proposes a new improved adaptive controller to effectively control voltage synchronization.And the convergence of the designed controller is strictly proved by using Lyapunov’s stability theorem.Finally,the effectiveness and feasibility of the designed controller in this paper are fully verified through detailed simulation experiments.After comparative analysis with the traditional adaptive controller,it is found that the newly designed controller can make the bus voltages of each distributed power source achieve synchronization more quickly,and is significantly superior to the traditional adaptive controller in terms of anti-interference performance.展开更多
Breakage is an important step in the resource processing chain.However,the mechanical crushing methods commonly used today suffer from low energy efficiency and high dust levels.Promoting environmental protection and ...Breakage is an important step in the resource processing chain.However,the mechanical crushing methods commonly used today suffer from low energy efficiency and high dust levels.Promoting environmental protection and improving energy efficiency are crucial to advancing China’s circular economy.Mining companies are actively exploring novel and innovative technologies to significantly cut down on operating costs and minimize emissions of dust and pollutants generated during processing.Recently,high voltage pulse discharge(HVPD)technology has received widespread attention and has been reported to have good application prospects in resource processing.This paper presents an extensive review of the operational principles of HVPD and the unique characteristics it engenders,such as non-polluting,selective material fragmentation,pre-weakening,pre-concentration,and enhanced permeability of coal seams.Additionally,this review explores the potential and obstacles confronting HVPD in industrial contexts,offering fresh insights for HVPD optimization and providing guidance and prospects for industrial deployment and further development.展开更多
The utilization of hybrid energy systems has necessitated to address the various Power Quality(PQ)concerns in Distributed Generation(DG)networks.Owing to the emergence of DG networks in recent times,it is envisaged fo...The utilization of hybrid energy systems has necessitated to address the various Power Quality(PQ)concerns in Distributed Generation(DG)networks.Owing to the emergence of DG networks in recent times,it is envisaged for every utility⁃grid⁃tied system to generate and utilize harmonic⁃less electric power.Therefore,the present research critically evaluates the operation of a utility⁃grid coordinated DG system and studies its islanding operation under faulted conditions.To achieve this,an Anti⁃Islanding Protection(AIP)scheme is developed which is capable of controlling the frequency and voltage variations.This scheme is operated by a coordinated operation of multivibrators.Their operation continuously traces the pre⁃defined limits of voltage,reactive,and real power,and matches with their reference values to avoid mismatch.It is revealed that,if the mismatched values of real and reactive power exceeded its threshold value of 0.1 p.u.,then the islanding condition is detected.Especially,the proposed system is assessed in two modes:utility⁃grid and islanding modes.In utility⁃grid mode,reactive power compensation is obtained by the control of voltage and frequency signals.However,in islanding mode,the real power requirement of the connected load is obtained with reduced harmonics under unsymmetrical faulted conditions.Incremental Conductance(IC)based Maximum Power Point Tracking(MPPT)technique ensures the extraction of maximum power under varying and stochastically atmospheric conditions.Simulation results reveal that the AIP scheme promptly disconnects the utility grid from the DG network in the minimum time during dynamic variations in frequency and voltage to prevent islanding.It is justified that there is violation of the considered threshold limits even under the faulted condition.The strategy of the switchgear scheme ensures the minimum detection time of the islanding operation.Total Harmonic Distortion(THD)is 0.26%for grid voltage.It validates according to the IEEE⁃1547 standard which stipulates that the THD of grid voltage must be less than 5%.Overall,satisfactory and accurate results are obtained,which are compared with the IEEE⁃1547 standard for validation.展开更多
Benzotriazole(BTA)-based A_(2)-A_1-D-A_1-A_(2)type wide-bandgap(WBG)non-fullerene acceptors(NFAs)have shown promising potential in indoor photovoltaic,and in-depth investigation of their structure-property relationshi...Benzotriazole(BTA)-based A_(2)-A_1-D-A_1-A_(2)type wide-bandgap(WBG)non-fullerene acceptors(NFAs)have shown promising potential in indoor photovoltaic,and in-depth investigation of their structure-property relationship is of great significance.Herein,we explored the chlorination effect of the side chain on the terminals.We introduced Cl atoms into the benzyl side chains in parent BTA5 to synthesize two NFAs,BTA5-Cl with mono-chlorinated benzyl groups and BTA5-2Cl containing bi-chlorinated benzyl groups.We chose D18-Cl with deep-energy levels and strong crystallinity to pair with these three acceptors,affording high photovoltage and photocurrent.With the stepwise chlorination,the open-circuit voltage(V_(OC))values decrease from 1.28,1.22,to 1.20 V,while the corresponding power conversion efficiencies(PCEs)improve from 5.07%,9.15%,to 10.96%.Compared with BTA5-based OSCs,introducing Cl atoms downshifts the energy levels and slightly increases the non-radiative energy loss(0.14<0.17<0.19 e V),resulting in a sequential decrease in VO C.However,more chlorine atom replacements produce more effective exciton dissociation,higher charge transfer,and balanced carrier mobility in the blend films,ultimately achieving better PCEs.This work indicates that chlorination of the benzyl group on the terminals can improve the device's performance,implying good application potential in indoor photovoltaics.展开更多
Uneven lithium deposition leading to lithium dendrite growth severely hampers the application of lithium-metal batteries.Modifying the collector with lithiophilic materials helps improve lithium deposition.For lithoph...Uneven lithium deposition leading to lithium dendrite growth severely hampers the application of lithium-metal batteries.Modifying the collector with lithiophilic materials helps improve lithium deposition.For lithophilic materials to modify the collector,the choice of cut-off voltage is very important.While excessively high cut-off voltages may compromise the stability of the modified layer and consequently disrupt ordered lithium deposition,conventional approaches typically employ lower cut-off voltages(particularly 0.1 V)to maintain modification layer stability.However,the 0.1 V cut-off voltage results in incomplete lithium stripping from the lithiophilic material surface.This phenomenon significantly diminishes the lithiophilic properties of the modified layer and consequently leads to substantial nucleation overpotential.Here,we propose to use a moderate cut-voltage stimulation effect to slow down the interfacial shielding effect of residual lithium metal on lithiophilic materials.By optimizing the cut-off voltage for the Cu@Sb_(2)S_(3)collector,the stability of the modified layer can be preserved while enabling the complete stripping of lithium metal from the surface of the lithophilic material.The asymmetric cell received the highest Coulombic efficiency(CE)when the lithium stripping cut-off voltage was set at 0.5 V relative to 0.1 and 2.0 V.At a current density of 1 mA cm^(-2)and a deposition capacity of1 m A h cm^(-2),the CE remained 98.6% at a cut-off voltage of 0.5 V after 140 cycles in an ether electrolyte without lithium nitrate.展开更多
基金supported by National Key R&D Program of China(No.2021YFB2401100)the Science and Technology Project of State Grid Corporation of China(No.5211DS22002C).
文摘The cluster DC voltage balancing control adopting zero-sequence voltage injection is appropriate for the starconnected cascaded H-bridge STATCOM because no zerosequence currents are generated in the three-phase three-wire system.However,as the zero-sequence voltage is expressed in trigonometric form,traditional control methods involve many complicated operations,such as the square-root,trigonometric operations,and inverse tangent operations.To simplify cluster voltage balancing control,this paper converts the zero-sequence voltage to the dq frame in a DC representation by introducing a virtually orthogonal variable,and the DC components of the zero-sequence voltage in the dq frame are regulated linearly by proportional integral regulators,rather than being calculated from uneven active powers in traditional controls.This removes all complicated operations.Finally,this paper presents simulation and experimental results for a 400 V±7.5 kvar star-connected STATCOM,in balanced and unbalanced scenarios,thereby verifying the effectiveness of the proposed control.
基金supported by the National Natural Science Foundation of China(52477221,52202296)the Natural Science Foundation of Shaanxi Province(2023KXJ-246,2022JQ-048)。
文摘Metal-insulator-metal aluminium electrolytic capacitors(MIM-AECs)combine high capacity-density and high breakdown field strength of solid AECs with high-frequency responsibility,wide workingtemperature window and waterproof properties of MIM nanocapacitors.However,interfacial atomic diffusion poses a major obstacle,preventing the high-voltage MIM-AECs exploitation and thereby hampering their potential and advantages in high-power and high-energy-density applications.Here,an innovative high-voltage MIM-AECs were fabricated.The AlPO_(4)buffer layer is formed on AlO(OH)/AAO/Al surface by using H_(3)PO_(4)treatment,then a stable van der Waals(vdW)SnO_(2)/AlPO_(4)/AAO/Al multilayer was constructed via atomic layer deposition(ALD)technology.Due to higher diffusion barrier and lower carrier migration of SnO_(2)/AlPO_(4)/AAO interfaces,Sn atom diffusion is inhibited and carrier acceleration by electric field is weakened,guaranteeing high breakdown field strength of dielectric AAO and avoiding local breakdown risks.Through partial etching to hydrated AlO(OH)by H_(3)PO_(4)treatment,the tunnel was further opened up to facilitate subsequent ALD-SnO_(2)entry,thus obtaining a high SnO_(2)coverage.The SnO_(2)/AlPO_(4)/AAO/Al capacitors show a comprehensive performance in high-voltage(260 V),hightemperature(335℃),high-humidity(100%RH)and high-frequency response(100 k Hz),outperforming commercial solid-state AECs,and high-energy density(8.6μWh/cm^(2)),markedly exceeding previously reported MIM capacitors.The work lays the foundation for next-generation capacitors with highvoltage,high-frequency,high-temperature and high-humidity resistance.
基金supported by the National Natural Science Foundation of China (Nos. 22379121, 62005216)Basic Public Welfare Research Program of Zhejiang (No. LQ22F050013)+1 种基金Zhejiang Province Key Laboratory of Flexible Electronics Open Fund (2023FE005)Shenzhen Foundation Research Program (No. JCYJ20220530112812028)。
文摘Fluoride-based electrolyte exhibits extraordinarily high oxidative stability in high-voltage lithium metal batteries(h-LMBs) due to the inherent low highest occupied molecular orbital(HOMO) of fiuorinated solvents. However, such fascinating properties do not bring long-term cyclability of h-LMBs. One of critical challenges is the interface instability in contacting with the Li metal anode, as fiuorinated solvents are highly susceptible to exceptionally reductive metallic Li attributed to its low lowest unoccupied molecular orbital(LUMO), which leads to significant consumption of the fiuorinated components upon cycling.Herein, attenuating reductive decomposition of fiuorinated electrolytes is proposed to circumvent rapid electrolyte consumption. Specifically, the vinylene carbonate(VC) is selected to tame the reduction decomposition by preferentially forming protective layer on the Li anode. This work, experimentally and computationally, demonstrates the importance of pre-passivation of Li metal anodes at high voltage to attenuate the decomposition of fiuoroethylene carbonate(FEC). It is expected to enrich the understanding of how VC attenuate the reactivity of FEC, thereby extending the cycle life of fiuorinated electrolytes in high-voltage Li-metal batteries.
基金financial support by National Natural Science Foundation(NNSF)of China(Nos.52202269,52002248,U23B2069,22309162)Shenzhen Science and Technology program(No.20220810155330003)+1 种基金Shenzhen Basic Research Project(No.JCYJ20190808163005631)Xiangjiang Lab(22XJ01007).
文摘Sodium-ion batteries hold great promise as next-generation energy storage systems.However,the high instability of the electrode/electrolyte interphase during cycling has seriously hindered the development of SIBs.In particular,an unstable cathode–electrolyte interphase(CEI)leads to successive electrolyte side reactions,transition metal leaching and rapid capacity decay,which tends to be exacerbated under high-voltage conditions.Therefore,constructing dense and stable CEIs are crucial for high-performance SIBs.This work reports localized high-concentration electrolyte by incorporating a highly oxidation-resistant sulfolane solvent with non-solvent diluent 1H,1H,5H-octafluoropentyl-1,1,2,2-tetrafluoroethyl ether,which exhibited excellent oxidative stability and was able to form thin,dense and homogeneous CEI.The excellent CEI enabled the O3-type layered oxide cathode NaNi_(1/3)Mn_(1/3)Fe_(1/3)O_(2)(NaNMF)to achieve stable cycling,with a capacity retention of 79.48%after 300 cycles at 1 C and 81.15%after 400 cycles at 2 C with a high charging voltage of 4.2 V.In addition,its nonflammable nature enhances the safety of SIBs.This work provides a viable pathway for the application of sulfolane-based electrolytes on SIBs and the design of next-generation high-voltage electrolytes.
文摘Fluctuating voltage levels in power grids necessitate automatic voltage regulators(AVRs)to ensure stability.This study examined the modeling and control of AVR in hydroelectric power plants using model predictive control(MPC),which utilizes an extensive mathe-matical model of the voltage regulation system to optimize the control actions over a defined prediction horizon.This predictive feature enables MPC to minimize voltage deviations while accounting for operational constraints,thereby improving stability and performance under dynamic conditions.Thefindings were compared with those derived from an optimal proportional integral derivative(PID)con-troller designed using the artificial bee colony(ABC)algorithm.Although the ABC-PID method adjusts the PID parameters based on historical data,it may be difficult to adapt to real-time changes in system dynamics under constraints.Comprehensive simulations assessed both frameworks,emphasizing performance metrics such as disturbance rejection,response to load changes,and resilience to uncertainties.The results show that both MPC and ABC-PID methods effectively achieved accurate voltage regulation;however,MPC excelled in controlling overshoot and settling time—recording 0.0%and 0.25 s,respectively.This demonstrates greater robustness compared to conventional control methods that optimize PID parameters based on performance criteria derived from actual system behavior,which exhibited settling times and overshoots exceeding 0.41 s and 5.0%,respectively.The controllers were implemented using MATLAB/Simulink software,indicating a significant advancement for power plant engineers pursuing state-of-the-art automatic voltage regulations.
基金funded by the State Grid Corporation Science and Technology Project(5108-202218280A-2-391-XG).
文摘The high proportion of uncertain distributed power sources and the access to large-scale random electric vehicle(EV)charging resources further aggravate the voltage fluctuation of the distribution network,and the existing research has not deeply explored the EV active-reactive synergistic regulating characteristics,and failed to realize themulti-timescale synergistic control with other regulatingmeans,For this reason,this paper proposes amultilevel linkage coordinated optimization strategy to reduce the voltage deviation of the distribution network.Firstly,a capacitor bank reactive power compensation voltage control model and a distributed photovoltaic(PV)activereactive power regulationmodel are established.Additionally,an external characteristicmodel of EVactive-reactive power regulation is developed considering the four-quadrant operational characteristics of the EVcharger.Amultiobjective optimization model of the distribution network is then constructed considering the time-series coupling constraints of multiple types of voltage regulators.A multi-timescale control strategy is proposed by considering the impact of voltage regulators on active-reactive EV energy consumption and PV energy consumption.Then,a four-stage voltage control optimization strategy is proposed for various types of voltage regulators with multiple time scales.Themulti-objective optimization is solved with the improvedDrosophila algorithmto realize the power fluctuation control of the distribution network and themulti-stage voltage control optimization.Simulation results validate that the proposed voltage control optimization strategy achieves the coordinated control of decentralized voltage control resources in the distribution network.It effectively reduces the voltage deviation of the distribution network while ensuring the energy demand of EV users and enhancing the stability and economic efficiency of the distribution network.
文摘Capacitive voltage transformers (CVTs) are essential in high-voltage systems. An accurate error assessment is crucial for precise energy metering. However, tracking real-time quantitative changes in capacitive voltage transformer errors, particularly minor variations in multi-channel setups, remains challenging. This paper proposes a method for online error tracking of multi-channel capacitive voltage transformers using a Co-Prediction Matrix. The approach leverages the strong correlation between in-phase channels, particularly the invariance of the signal proportions among them. By establishing a co-prediction matrix based on these proportional relationships, The influence of voltage changes on the primary measurements is mitigated. Analyzing the relationships between the co-prediction matrices over time allows for inferring true measurement errors. Experimental validation with real-world data confirms the effectiveness of the method, demonstrating its capability to continuously track capacitive voltage transformer measurement errors online with precision over extended durations.
文摘This study examines the influence of magnetic field and temperature on the transient voltage of a polycrystalline silicon radial junction solar cell in a dynamic regime under multispectral illumination. Radial junction solar cells represent a major advancement in photovoltaic technologies, as they optimize light absorption and charge collection efficiency. The focus is on the impact of the magnetic field and temperature on the decay of transient voltage, which provides crucial information on recombination processes and the lifetime of minority carriers. The results reveal that the magnetic field tends to increase the transient voltage by directly affecting the transient electron density. Indeed, for B > 7 × 10−5 T, the magnetic field prolongs the relaxation time by increasing the transient voltage amplitude. Additionally, rising temperatures accelerate (ranging from 290 K to 450 K) recombination processes, thereby reducing the transient voltage, although this effect is moderated by the presence of a magnetic field. The study highlights the complex interaction between magnetic field and temperature, with significant impacts on the transient behaviour.
文摘With the rapid integration of renewable energy sources,modern power systems are increasingly challenged by heightened volatility and uncertainty.Doubly-fed variable-speed pumped storage units(DFVS-PSUs)have emerged as promising technologies for mitigating grid oscillations and enhancing system flexibility.However,the excitation converters in DFVS-PSUs are prone to significant issues such as elevated common-mode voltage(CMV)and neutral-point voltage(NPV)fluctuations,which can lead to electromagnetic interference and degrade transient performance.To address these challenges,an optimized virtual space vector pulse width modulation(OVSVPWM)strategy is proposed,aiming to suppress CMV and NPV simultaneously through coordinated multi-objective control.Specifically,a dynamic feedback mechanism is introduced to adjust the balancing factor of basic vectors in the synthesized virtual small vector in real-time,achieving autonomous balancing of the NPV.To address the excessive switching actions introduced by the OVSVPWM strategy,a phase duty ratio-based sequence reconstruction method is adopted,which reduces the total number of switching actions to half of the original.A zero-level buffering scheme is employed to reconstruct the single-phase voltage-level output sequence,achieving peak CMV suppression down to udc/6.Simulation results demonstrate that the proposed strategy significantly improves electromagnetic compatibility and operational stability while maintaining high power quality.
基金supported by the National Key Laboratory of Materials Behavior and Evaluation Technology in Space Environment(No.6142910220208)National Natural Science Foundation of China(Nos.12105341 and 12035019)the opening fund of Key Laboratory of Silicon Device and Technology,Chinese Academy of Sciences(No.KLSDTJJ2022-3).
文摘This paper explores the impact of back-gate bias (V_(soi)) and supply voltage (V_(DD)) on the single-event upset (SEU) cross section of 0.18μm configurable silicon-on-insulator static random-access memory (SRAM) under high linear energy transfer heavyion experimentation.The experimental findings demonstrate that applying a negative back-gate bias to NMOS and a positive back-gate bias to PMOS enhances the SEU resistance of SRAM.Specifically,as the back-gate bias for N-type transistors(V_(nsoi)) decreases from 0 to-10 V,the SEU cross section decreases by 93.23%,whereas an increase in the back-gate bias for P-type transistors (V_(psoi)) from 0 to 10 V correlates with an 83.7%reduction in SEU cross section.Furthermore,a significant increase in the SEU cross section was observed with increase in supply voltage,as evidenced by a 159%surge at V_(DD)=1.98 V compared with the nominal voltage of 1.8 V.To explore the physical mechanisms underlying these experimental data,we analyzed the dependence of the critical charge of the circuit and the collected charge on the bias voltage by simulating SEUs using technology computer-aided design.
文摘In this paper, we proposed an output voltage stabilization of a DC-DC Zeta converter using hybrid control. We modeled the Zeta converter under continuous conduction mode operation. We derived a switching control law that brings the output voltage to the desired level. Due to infinite switching occurring at the desired level, we enhanced the switching control law by allowing a sizeable output voltage ripple. We derived mathematical models that allow one to choose the desired switching frequency. In practice, the existence of the non-ideal properties of the Zeta converter results in steady-state output voltage error. By analyzing the power loss in the zeta converter, we proposed an improved switching control law that eliminates the steady-state output voltage error. The effectiveness of the proposed method is illustrated with simulation results.
基金funded by the Basic Science(Natural Science)Research Project of Colleges and Universities in Jiangsu Province,Grant Number 22KJD470002.
文摘The active equalization of lithium-ion batteries involves transferring energy from high-voltage cells to low-voltage cells,ensuring consistent voltage levels across the battery pack and maintaining safety.This paper presents a voltage balancing circuit and control method.First,a single capacitor method is used to design the circuit topology for energy transfer.Next,real-time voltage detection and control are employed to balance energy between cells.Finally,simulation and experimental results demonstrate the effectiveness of the proposed method,achieving balanced voltages of 3.97 V from initial voltages of 4.10,3.97,and 3.90 V.The proposed circuit is simple,reliable,and effectively prevents overcharge and overdischarge.
文摘Voltage substrate mapping is a promising tool for the treatment of atrial fibrillation(AF).It is helpful to detect atrial fibrosis,which includes areas with low bipolar voltage,heterogeneous conduction properties,and shortened effective refractory period.The voltage amplitude is typically defined as the maximal peakto-peak level within a specified time window of interest.Contemporary electroanatomic mapping platforms now enable many thousands of data points to be mapped,so that a geometric model of the atrial endocardium is constructable over a short period of time.This mapping procedure is often done with bipolar electrodes to cancel the far-field signal.The recording site coordinates are projected onto an atrial shell,with interpolation of the voltage data across the shell surface.The amplitude of the recorded bipolar electrogram depicted on the threedimensional shell provides detailed information for substrate mapping.Wherever there are areas of low peak-to-peak voltage,it is thought to mark the presence of abnormal tissue properties and conduction.However,uncontrolled variables and environmental factors affecting voltage level include the oncoming electrical activation wavefront direction,the catheter incidence angle,the force applied to the catheter,and the region-variable shape and structure of atrial tissue.Techniques and settings to acquire atrial voltage data for AF analysis have not been standardized.Methods to characterize atrial electrograms are also presently limited.These factors affect quality and reproducibility of the mapping results.Herein,voltage substrate mapping and its variables pertaining to AF and radiofrequency ablation are described and discussed,with suggestions for future work efforts.
文摘Efficient battery charging requires a power conversion system capable of providing precise voltage regulation tailored to the battery’s needs.This study develops a buck converter with a 36 V input for charging a 14 V battery using the Constant Voltage(CV)method.The system is designed to ensure safe and efficient charging while protecting the battery from overcharging and extending its lifespan.In the proposed design,the converter maintains a constant output voltage while the charging current decreases as the battery approaches full capacity.Pulse Width Modulation(PWM)is used as a control strategy to modify the duty cycle of the converter.This keeps the voltage output stable whenever the load changes.The design process involves simulation and experimental validation to evaluate the system’s performance and efficiency.The test results show the significant impact of Proportional-Integral-Derivative(PID)control on the stability of the output voltage to meet the requirements for 14 V battery charging and the efficiency of the battery charging process.The output voltage becomes more stable,with reduced oscillation and minimal steadystate error.The State of Charge(SOC)increases more stably,controllably,and efficiently thanks to the PID controller’s ability to adjust the duty cycle in real time based on system feedback.This dynamic adjustment ensures that the output current and voltage remain within the optimal range,which directly improves the battery charging process.In addition,PID control significantly improves the dynamic response of the system,reducing overshoot and settling time while maintaining precise voltage regulation.This speeds up the battery charging process and contributes to better energy efficiency,reduced power loss,and extended battery life.This research provides a reliable and cost-effective solution for applications in electric vehicles,renewable energy systems,and other battery-powered devices.
基金supported by the National Natural Science Foundation of China(Nos.51767017 and 51867015)the Basic Research and Innovation Group Project of Gansu(No.18JR3RA13)the Major Science and Technology Project of Gansu(No.19ZD2GA003).
文摘This paper deeply introduces a brand-new research method for the synchronous characteristics of DC microgrid bus voltage and an improved synchronous control strategy.This method mainly targets the problem of bus voltage oscillation caused by the bifurcation behavior of DC microgrid converters.Firstly,the article elaborately establishes a mathematical model of a single distributed power source with hierarchical control.On this basis,a smallworld network model that can better adapt to the topology structure of DC microgrids is further constructed.Then,a voltage synchronization analysis method based on the main stability function is proposed,and the synchronous characteristics of DC bus voltage are deeply studied by analyzing the size of the minimum non-zero eigenvalue.In view of the situation that the line coupling strength between distributed power sources is insufficient to achieve bus voltage synchronization,this paper innovatively proposes a new improved adaptive controller to effectively control voltage synchronization.And the convergence of the designed controller is strictly proved by using Lyapunov’s stability theorem.Finally,the effectiveness and feasibility of the designed controller in this paper are fully verified through detailed simulation experiments.After comparative analysis with the traditional adaptive controller,it is found that the newly designed controller can make the bus voltages of each distributed power source achieve synchronization more quickly,and is significantly superior to the traditional adaptive controller in terms of anti-interference performance.
基金Foundation item:Project(2023YFC2909000) supported by the National Key R&D Program for Young Scientists,ChinaProject(2023JH3/10200010) supported by the Excellent Youth Natural Science Foundation of Liaoning Province,China+3 种基金Project (XLYC2203167) supported by the Liaoning Revitalization Talents Program,ChinaProject(RC231175) supported by the Mid-career and Young Scientific and Technological Talents Program of Shenyang,ChinaProject(2023A03003-2) supported by the Key Special Program of Xinjiang,ChinaProject(N2301026) supported by the Fundamental Research Funds for the Central Universities,China。
文摘Breakage is an important step in the resource processing chain.However,the mechanical crushing methods commonly used today suffer from low energy efficiency and high dust levels.Promoting environmental protection and improving energy efficiency are crucial to advancing China’s circular economy.Mining companies are actively exploring novel and innovative technologies to significantly cut down on operating costs and minimize emissions of dust and pollutants generated during processing.Recently,high voltage pulse discharge(HVPD)technology has received widespread attention and has been reported to have good application prospects in resource processing.This paper presents an extensive review of the operational principles of HVPD and the unique characteristics it engenders,such as non-polluting,selective material fragmentation,pre-weakening,pre-concentration,and enhanced permeability of coal seams.Additionally,this review explores the potential and obstacles confronting HVPD in industrial contexts,offering fresh insights for HVPD optimization and providing guidance and prospects for industrial deployment and further development.
文摘The utilization of hybrid energy systems has necessitated to address the various Power Quality(PQ)concerns in Distributed Generation(DG)networks.Owing to the emergence of DG networks in recent times,it is envisaged for every utility⁃grid⁃tied system to generate and utilize harmonic⁃less electric power.Therefore,the present research critically evaluates the operation of a utility⁃grid coordinated DG system and studies its islanding operation under faulted conditions.To achieve this,an Anti⁃Islanding Protection(AIP)scheme is developed which is capable of controlling the frequency and voltage variations.This scheme is operated by a coordinated operation of multivibrators.Their operation continuously traces the pre⁃defined limits of voltage,reactive,and real power,and matches with their reference values to avoid mismatch.It is revealed that,if the mismatched values of real and reactive power exceeded its threshold value of 0.1 p.u.,then the islanding condition is detected.Especially,the proposed system is assessed in two modes:utility⁃grid and islanding modes.In utility⁃grid mode,reactive power compensation is obtained by the control of voltage and frequency signals.However,in islanding mode,the real power requirement of the connected load is obtained with reduced harmonics under unsymmetrical faulted conditions.Incremental Conductance(IC)based Maximum Power Point Tracking(MPPT)technique ensures the extraction of maximum power under varying and stochastically atmospheric conditions.Simulation results reveal that the AIP scheme promptly disconnects the utility grid from the DG network in the minimum time during dynamic variations in frequency and voltage to prevent islanding.It is justified that there is violation of the considered threshold limits even under the faulted condition.The strategy of the switchgear scheme ensures the minimum detection time of the islanding operation.Total Harmonic Distortion(THD)is 0.26%for grid voltage.It validates according to the IEEE⁃1547 standard which stipulates that the THD of grid voltage must be less than 5%.Overall,satisfactory and accurate results are obtained,which are compared with the IEEE⁃1547 standard for validation.
基金support from the National Natural Science Foundation of China(Nos.52373176,52073067)。
文摘Benzotriazole(BTA)-based A_(2)-A_1-D-A_1-A_(2)type wide-bandgap(WBG)non-fullerene acceptors(NFAs)have shown promising potential in indoor photovoltaic,and in-depth investigation of their structure-property relationship is of great significance.Herein,we explored the chlorination effect of the side chain on the terminals.We introduced Cl atoms into the benzyl side chains in parent BTA5 to synthesize two NFAs,BTA5-Cl with mono-chlorinated benzyl groups and BTA5-2Cl containing bi-chlorinated benzyl groups.We chose D18-Cl with deep-energy levels and strong crystallinity to pair with these three acceptors,affording high photovoltage and photocurrent.With the stepwise chlorination,the open-circuit voltage(V_(OC))values decrease from 1.28,1.22,to 1.20 V,while the corresponding power conversion efficiencies(PCEs)improve from 5.07%,9.15%,to 10.96%.Compared with BTA5-based OSCs,introducing Cl atoms downshifts the energy levels and slightly increases the non-radiative energy loss(0.14<0.17<0.19 e V),resulting in a sequential decrease in VO C.However,more chlorine atom replacements produce more effective exciton dissociation,higher charge transfer,and balanced carrier mobility in the blend films,ultimately achieving better PCEs.This work indicates that chlorination of the benzyl group on the terminals can improve the device's performance,implying good application potential in indoor photovoltaics.
基金support from the National Natural Science Foundation of China(22179006)the National Key Research and Development Program of China(2024YFF0505900)+1 种基金the Key Research and Development Program of Henan province,China(231111242500)the SINOPEC project(223128)。
文摘Uneven lithium deposition leading to lithium dendrite growth severely hampers the application of lithium-metal batteries.Modifying the collector with lithiophilic materials helps improve lithium deposition.For lithophilic materials to modify the collector,the choice of cut-off voltage is very important.While excessively high cut-off voltages may compromise the stability of the modified layer and consequently disrupt ordered lithium deposition,conventional approaches typically employ lower cut-off voltages(particularly 0.1 V)to maintain modification layer stability.However,the 0.1 V cut-off voltage results in incomplete lithium stripping from the lithiophilic material surface.This phenomenon significantly diminishes the lithiophilic properties of the modified layer and consequently leads to substantial nucleation overpotential.Here,we propose to use a moderate cut-voltage stimulation effect to slow down the interfacial shielding effect of residual lithium metal on lithiophilic materials.By optimizing the cut-off voltage for the Cu@Sb_(2)S_(3)collector,the stability of the modified layer can be preserved while enabling the complete stripping of lithium metal from the surface of the lithophilic material.The asymmetric cell received the highest Coulombic efficiency(CE)when the lithium stripping cut-off voltage was set at 0.5 V relative to 0.1 and 2.0 V.At a current density of 1 mA cm^(-2)and a deposition capacity of1 m A h cm^(-2),the CE remained 98.6% at a cut-off voltage of 0.5 V after 140 cycles in an ether electrolyte without lithium nitrate.