Fast-charging and low temperature operation are of vital importance for the further development of lithium-ion batteries(LIBs),which is hindered by the utilization of conventional carbonate-based electrolytes due to t...Fast-charging and low temperature operation are of vital importance for the further development of lithium-ion batteries(LIBs),which is hindered by the utilization of conventional carbonate-based electrolytes due to their slow kinetics,narrow operating temperature and voltage range.Herein,an acetonitrile(AN)-based localized high-concentration electrolyte(LHCE)is proposed to retain liquid state and high ionic conductivity at ultra-low temperatures while possessing high oxidation stability.We originally reveal the excellent thermal shielding effect of non-solvating diluent to prevent the aggregation of Li^(+) solvates as temperature drops,maintaining the merits of fast Li transport and facile desolvation as at room temperature,which bestows the graphite electrode with remarkable low temperature performance(264 mA h g^(-1) at-20 C).Remarkably,an extremely high capacity retention of 97%is achieved for high-voltage high-energy graphite||NCM batteries after 250 cycles at-20 C,and a high capacity of 110 mA h g^(-1)(71%of its room-temperature capacity)is retained at-30°C.The study unveils the key role of the non-solvating diluents and provides instructive guidance in designing electrolytes towards fast-charging and low temperature LIBs.展开更多
Lithium-ion batteries(LIBs)with the“double-high”characteristics of high energy density and high power density are in urgent demand for facilitating the development of advanced portable electronics.However,the lithiu...Lithium-ion batteries(LIBs)with the“double-high”characteristics of high energy density and high power density are in urgent demand for facilitating the development of advanced portable electronics.However,the lithium ion(Li+)-storage performance of the most commercialized lithium cobalt oxide(LiCoO_(2),LCO)cathodes is still far from satisfactory in terms of high-voltage and fast-charging capabilities for reaching the double-high target.Herein,we systematically summarize and discuss high-voltage and fast-charging LCO cathodes,covering in depth the key fundamental challenges,latest advancements in modification strategies,and future perspectives in this field.Comprehensive and elaborated discussions are first presented on key fundamental challenges related to structural degradation,interfacial instability,the inhomogeneity reactions,and sluggish interfacial kinetics.We provide an instructive summary of deep insights into promising modification strategies and underlying mechanisms,categorized into element doping(Li-site,cobalt-/oxygen-site,and multi-site doping)for improved Li+diffusivity and bulkstructure stability;surface coating(dielectrics,ionic/electronic conductors,and their combination)for surface stability and conductivity;nanosizing;combinations of these strategies;and other strategies(i.e.,optimization of the electrolyte,binder,tortuosity of electrodes,charging protocols,and prelithiation methods).Finally,forward-looking perspectives and promising directions are sketched out and insightfully elucidated,providing constructive suggestions and instructions for designing and realizing high-voltage and fast-charging LCO cathodes for next-generation double-high LIBs.展开更多
Recent technological advancements,such as portable electronics and electric vehicles,have created a pressing need for more efficient energy storage solutions.Lithium-ion batteries(LIBs)have been the preferred choice f...Recent technological advancements,such as portable electronics and electric vehicles,have created a pressing need for more efficient energy storage solutions.Lithium-ion batteries(LIBs)have been the preferred choice for these applications,with graphite being the standard anode material due to its stability.However,graphite falls short of meeting the growing demand for higher energy density,possessing a theoretical capacity that lags behind.To address this,researchers are actively seeking alternative materials to replace graphite in commercial batteries.One promising avenue involves lithiumalloying materials like silicon and phosphorus,which offer high theoretical capacities.Carbon-silicon composites have emerged as a viable option,showing improved capacity and performance over traditional graphite or pure silicon anodes.Yet,the existing methods for synthesizing these composites remain complex,energy-intensive,and costly,preventing widespread adoption.A groundbreaking approach is presented here:the use of a laser writing strategy to rapidly transform common organic carbon precursors and silicon blends into efficient“graphenic silicon”composite thin films.These films exhibit exceptional structural and energy storage properties.The resulting three-dimensional porous composite anodes showcase impressive attributes,including ultrahigh silicon content,remarkable cyclic stability(over 4500 cycles with∼40%retention),rapid charging rates(up to 10 A g^(-1)),substantial areal capacity(>5.1 mAh cm^(-2)),and excellent gravimetric capacity(>2400 mAh g^(-1) at 0.2 A g^(-1)).This strategy marks a significant step toward the scalable production of high-performance LIB materials.Leveraging widely available,cost-effective precursors,the laser-printed“graphenic silicon”composites demonstrate unparalleled performance,potentially streamlining anode production while maintaining exceptional capabilities.This innovation not only paves the way for advanced LIBs but also sets a precedent for transforming various materials into high-performing electrodes,promising reduced complexity and cost in battery production.展开更多
Fabricating low-strain and fast-charging silicon-carbon composite anodes is highly desired but remains a huge challenge for lithium-ion batteries.Herein,we report a unique silicon-carbon composite fabricated by unifor...Fabricating low-strain and fast-charging silicon-carbon composite anodes is highly desired but remains a huge challenge for lithium-ion batteries.Herein,we report a unique silicon-carbon composite fabricated by uniformly dis-persing amorphous Si nanodots(SiNDs)in carbon nanospheres(SiNDs/C)that are welded on the wall of the macroporous carbon framework(MPCF)by vertical graphene(VG),labeled as MPCF@VG@SiNDs/C.The high dispersity and amor-phous features of ultrasmall SiNDs(~0.7 nm),the flexible and directed electron/Li+transport channels of VG,and the MPCF impart the MPCF@VG@SiNDs/C more lithium storage sites,rapid Li+transport path,and unique low-strain property during Li+storage.Consequently,the MPCF@VG@SiNDs/C exhibits high cycle stability(1301.4 mAh g^(-1) at 1 A g^(-1) after 1000 cycles without apparent decay)and high rate capacity(910.3 mAh g^(-1),20 A g^(-1))in half cells based on industrial electrode standards.The assembled pouch full cell delivers a high energy density(1694.0 Wh L^(-1);602.8 Wh kg^(-1))and an excellent fast-charging capability(498.5 Wh kg^(-1),charging for 16.8 min at 3 C).This study opens new possibilities for preparing advanced silicon-carbon com-posite anodes for practical applications.展开更多
Lithium-ion batteries(LIBs)with fast-charging capability are essential for enhancing consumer experience and accelerating the global market adoption of electric vehicles.However,achieving fast-charging capability with...Lithium-ion batteries(LIBs)with fast-charging capability are essential for enhancing consumer experience and accelerating the global market adoption of electric vehicles.However,achieving fast-charging capability without compromising energy density,cycling lifespan,and safety of LIBs remains a significant challenge due to the formation of dendritic Li metal on graphite anode under fast charging condition.In view of this,the fundamentals for the dendritic metallic Li formation and the strategies for suppressing metallic Li plating based on analyzing the entire Li^(+)transport pathway at the anode including electrolyte,pore structure of electrode,and surface and bulk of materials are summarized and discussed in this review.Besides,we highlight the importance of designing thick electrodes with fast Li^(+)transport kinetics and comprehensively understanding the interaction between solid electrolyte interphase(SEI)and Li^(+)migration in order to avoid the formation of dendritic Li metal in practical fast-charging batteries.Finally,the regulation of Li metal plating with plane morphology,instead of dendritic structure,on the surface of graphite electrode under fast-charging condition is analyzed as a future direction to achieve higher energy density of batteries without safety concerns.展开更多
High-energy–density lithium-ion batteries(LIBs)that can be safely fast-charged are desirable for electric vehicles.However,sub-optimal lithiation potential and low capacity of commonly used LIBs anode cause safety is...High-energy–density lithium-ion batteries(LIBs)that can be safely fast-charged are desirable for electric vehicles.However,sub-optimal lithiation potential and low capacity of commonly used LIBs anode cause safety issues and low energy density.Here we hypothesize that a cobalt vanadate oxide,Co_(2)VO_(4),can be attractive anode material for fast-charging LIBs due to its high capacity(~1000 mAh g^(−1))and safe lithiation potential(~0.65 V vs.Li^(+)/Li).The Li+diffusion coefficient of Co2VO4 is evaluated by theoretical calculation to be as high as 3.15×10^(-10) cm^(2) s^(−1),proving Co_(2)VO_(4) a promising anode in fast-charging LIBs.A hexagonal porous Co2VO4 nanodisk(PCVO ND)structure is designed accordingly,featuring a high specific surface area of 74.57 m^(2) g^(−1) and numerous pores with a pore size of 14 nm.This unique structure succeeds in enhancing Li^(+) and electron transfer,leading to superior fast-charging performance than current commercial anodes.As a result,the PCVO ND shows a high initial reversible capacity of 911.0 mAh g^(−1) at 0.4 C,excellent fast-charging capacity(344.3 mAh g^(−1) at 10 C for 1000 cycles),outstanding long-term cycling stability(only 0.024% capacity loss per cycle at 10 C for 1000 cycles),confirming the commercial feasibility of PCVO ND in fast-charging LIBs.展开更多
With the ever-growing application of lithium-ion batteries(LIBs), their fast-charging technology has attracted great interests of scientists. However, growth of lithium dendrites during fast charge of the bat teries w...With the ever-growing application of lithium-ion batteries(LIBs), their fast-charging technology has attracted great interests of scientists. However, growth of lithium dendrites during fast charge of the bat teries with high energy density may pose great threats to the operation and cause serious safety issues Herein, we prepared a functional separator with an ultra-thin(20 nm) layer of Au nanoparticles deposited by evaporation coating method which could regulate growth direction and morphology of the lithium dendrites, owing to nearly zero overpotential of lithium meal nucleation on lithiated Au. Once the Li den drites are about to form on the graphite anode during fast charging(or lithiation), they plate predomi nantly on the Au deposited separator rather than on the graphite. Such selective deposition does no compromise the electrochemical performance of batteries under normal cycling. More importantly, i enables the better cycling stability of batteries at fast charge condition. The Li/Graphite cells with Au nanoparticles coated separator could cycle stably with a high areal capacity retention of 90.5% over 95 cycles at the current density of 0.72 m A cm^(-2). The functional separator provides an effective strategy to adjust lithium plating position at fast charge to ensure high safety of batteries without a compromise on the energy density of LIBs.展开更多
Fast-charging lithium-ion batteries are highly required,especially in reducing the mileage anxiety of the widespread electric vehicles.One of the biggest bottlenecks lies in the sluggish kinetics of the Li^(+)intercal...Fast-charging lithium-ion batteries are highly required,especially in reducing the mileage anxiety of the widespread electric vehicles.One of the biggest bottlenecks lies in the sluggish kinetics of the Li^(+)intercalation into the graphite anode;slow intercalation will lead to lithium metal plating,severe side reactions,and safety concerns.The premise to solve these problems is to fully understand the reaction pathways and rate-determining steps of graphite during fast Li^(+)intercalation.Herein,we compare the Li^(+)diffusion through the graphite particle,interface,and electrode,uncover the structure of the lithiated graphite at high current densities,and correlate them with the reaction kinetics and electrochemical performances.It is found that the rate-determining steps are highly dependent on the particle size,interphase property,and electrode configuration.Insufficient Li^(+)diffusion leads to high polarization,incomplete intercalation,and the coexistence of several staging structures.Interfacial Li^(+)diffusion and electrode transportation are the main rate-determining steps if the particle size is less than 10μm.The former is highly dependent on the electrolyte chemistry and can be enhanced by constructing a fluorinated interphase.Our findings enrich the understanding of the graphite structural evolution during rapid Li^(+)intercalation,decipher the bottleneck for the sluggish reaction kinetics,and provide strategic guidelines to boost the fast-charging performance of graphite anode.展开更多
High theoretical capacity and unique layered structures make MoS_(2)a promising lithium-ion battery anode material.However,the anisotropic ion transport in layered structures and the poor intrinsic conductivity of MoS...High theoretical capacity and unique layered structures make MoS_(2)a promising lithium-ion battery anode material.However,the anisotropic ion transport in layered structures and the poor intrinsic conductivity of MoS_(2)lead to unacceptable ion transport capability.Here,we propose in-situ construction of interlayer electrostatic repulsion caused by Co^(2+)substituting Mo^(4+)between MoS_(2)layers,which can break the limitation of interlayer van der Waals forces to fabricate monolayer MoS_(2),thus establishing isotropic ion transport paths.Simultaneously,the doped Co atoms change the electronic structure of monolayer MoS_(2),thus improving its intrinsic conductivity.Importantly,the doped Co atoms can be converted into Co nanoparticles to create a space charge region to accelerate ion transport.Hence,the Co-doped monolayer MoS_(2)shows ultrafast lithium ion transport capability in half/full cells.This work presents a novel route for the preparation of monolayer MoS_(2)and demonstrates its potential for application in fast-charging lithium-ion batteries.展开更多
Fast charging is considered a promising protocol for raising the charging efficiency of electric vehicles.However,high currents applied to Lithium-ion(Li-ion)batteries inevitably accelerate the degradation and shorten...Fast charging is considered a promising protocol for raising the charging efficiency of electric vehicles.However,high currents applied to Lithium-ion(Li-ion)batteries inevitably accelerate the degradation and shorten their lifetime.This work designs a multi-step fast-charging method to extend the lifetime of LiNi0.5Co0.2Mn0.3O2(NMC)/graphite Li-ion batteries based on the studies of half cells and investigates the aging mechanisms for different charging methods.The degradation has been studied from both full cell behaviour and materials perspectives through a combination of non-destructive diagnostic methods and post-mortem analysis.In the proposed multi-step charging protocol,the state-of-charge(SOC)profile is subdivided into five ranges,and the charging current is set differently for different SOC ranges.One of the designed multi-step fast charging protocols is shown to allow for a 200 full equivalent cycles longer lifetime as compared to the standard charging method,while the charging time is reduced by 20%.From the incremental capacity analysis and electrical impedance spectroscopy,the loss of active materials and lithium inventory on the electrodes,as well as an increase in internal resistance for the designed multistep constant-current-constant-voltage(MCCCV)protocol have been found to be significantly lower than for the standard charging method.Post-mortem analysis shows that cells aged by the designed MCCCV fast charging protocol exhibit less graphite exfoliation and crystallization damage,as well as a reduced solid electrolyte interphase(SEI)layer growth on the anode,leading to a lower Rseiresistance and extended lifetime.展开更多
High-voltage and fast-charging LiCoO_(2)(LCO)is key to high-energy/power-density Li-ion batteries.However,unstable surface structure and unfavorable electronic/ionic conductivity severely hinder its high-voltage fast-...High-voltage and fast-charging LiCoO_(2)(LCO)is key to high-energy/power-density Li-ion batteries.However,unstable surface structure and unfavorable electronic/ionic conductivity severely hinder its high-voltage fast-charging cyclability.Here,we construct a Li/Na-B-Mg-Si-O-F-rich mixed ion/electron interface network on the 4.65 V LCO electrode to enhance its rate capability and long-term cycling stability.Specifically,the resulting artificial hybrid conductive network enhances the reversible conversion of Co^(3+)/^(4+)/O_(2)/nredox by the interfacial ion–electron cooperation and suppresses interface side reactions,inducing an ultrathin yet compact cathode electrolyte interphase.Simultaneously,the derived near-surface Na+/Mg2+/Si^(4+)-pillared local intercalation structure greatly promotes the Li^(+)diffusion around the 4.55 V phase transition and stabilizes the cathode interface.Finally,excellent 3 C(1 C=274 mA g1)fast charging performance is demonstrated with 73.8%capacity retention over 1000 cycles.Our findings shed new insights to the fundamental mechanism of interfacial ion/electron synergy in stabilizing and enhancing fast-charging cathode materials.展开更多
The sluggish lithium-ion(Li-ion)transport kinetics in graphite anode hinders its application in fast-charging Li-ion batteries(LIBs).Here,we develop an ionpumping interphase(IPI)on graphdiyne(GDY)/graphite heterojunct...The sluggish lithium-ion(Li-ion)transport kinetics in graphite anode hinders its application in fast-charging Li-ion batteries(LIBs).Here,we develop an ionpumping interphase(IPI)on graphdiyne(GDY)/graphite heterojunction anodes to boost the ionic transport kinetics and enable high-performance,fast-charging LIBs.The IPI changed the ion solvation/desolvation environment by covalent/non-covalent interactions with Li ions or solvents to optimize solid-electrolyte interphase(SEI)and regulate Li-ion transport behavior.We studied the in situ growth of few-layer GDY on graphite surface(GDY/graphite)as the IPI and found that the strong interaction between GDY and Li ions enabled surface-induced modification of the ion solvation behavior and surface-assisted desolvation effect to accelerate the Li-ion desolvation process.A functional anion-derived SEI layer with improved Li-ion conductivity was created.Together with the generated built-in electric field at GDY/graphite hetero-interface self-pumping Li ions to intercalate into the graphite,the Li-ion transport kinetics was significantly enhanced to effectively eliminate Li plating and large voltage polarization of the graphite anodes.A fast Li intercalation in GDY/graphite without Li oversaturation at the edge of the graphite was directly observed.The superior performance with high capacity(139.2 mA h g^(-1))and long lifespan(1650 cycles)under extremely fast-charging conditions(20 C,1 C=372 mA g^(-1))was achieved on GDY/graphite anodes.Even at low temperatures(-20℃),a specific capacity of 128.4 mA h g^(-1) was achieved with a capacity retention of 80%after 500 cycles at a 2 C rate.展开更多
Efficient fast-charging technology is necessary for the extension of the driving range of electric vehicles.However,lithium-ion cells generate immense heat at high-current charging rates.In order to address this probl...Efficient fast-charging technology is necessary for the extension of the driving range of electric vehicles.However,lithium-ion cells generate immense heat at high-current charging rates.In order to address this problem,an efficient fast charging–cooling scheduling method is urgently needed.In this study,a liquid cooling-based thermal management system equipped with mini-channels was designed for the fastcharging process of a lithium-ion battery module.A neural network-based regression model was proposed based on 81 sets of experimental data,which consisted of three sub-models and considered three outputs:maximum temperature,temperature standard deviation,and energy consumption.Each sub-model had a desirable testing accuracy(99.353%,97.332%,and 98.381%)after training.The regression model was employed to predict all three outputs among a full dataset,which combined different charging current rates(0.5C,1C,1.5C,2C,and 2.5C(1C=5 A))at three different charging stages,and a range of coolant rates(0.0006,0.0012,and 0.0018 kg·s^(-1)).An optimal charging–cooling schedule was selected from the predicted dataset and was validated by the experiments.The results indicated that the battery module’s state of charge value increased by 0.5 after 15 min,with an energy consumption lower than 0.02 J.The maximum temperature and temperature standard deviation could be controlled within 33.35 and 0.8C,respectively.The approach described herein can be used by the electric vehicles industry in real fast-charging conditions.Moreover,optimal fast charging-cooling schedule can be predicted based on the experimental data obtained,that in turn,can significantly improve the efficiency of the charging process design as well as control energy consumption during cooling.展开更多
Hybrid Na-ion capacitors(NICs)have received considerable interests owing to their low-cost,high-safety,and rapidly charging energy-storage characteristics.The NICs are composed of a capacitor-type cathode and a batter...Hybrid Na-ion capacitors(NICs)have received considerable interests owing to their low-cost,high-safety,and rapidly charging energy-storage characteristics.The NICs are composed of a capacitor-type cathode and a battery-type anode.The major challenge for NICs is to search for suitable electrode materials to overcome the sluggish diffusion of Na^(+)in the anode.Herein,ultrafine vanadium sulfide is encapsulated in carbon fiber(V_(3)S_(4)@CNF)as a self-supported electrode by electrospinning and in situ sulfurization.The carbon cladding and one-dimensional(ID)nanofiber network-like structure could alleviate the volume expansion of V_(3)S_(4)during Na^(+)de-/intercalation process.Consequently,the V_(3)S_(4)@CNF anode exhibited a pseudocapacitive sodium storage in terms of large Na^(+)-storage capacity(476 mAh·g^(-1)at 0.1A·g^(-1)),high-rate capability(290 mAh·g^(-1)at 20.0 A·g^(-1))and excellent cycling stability(95%capacity retention for1500 cycles at 2.0 A·g^(-1))in Na half-cells.By employing V_(3)S_(4)@CNF as the anode and the activated carbon(AC)cathode,the as-assembled NICs could deliver a high energy density of 110 Wh·kg^(-1)at a power density of200 W·kg^(-1).Even at a high power of 10,000 W·kg^(-1),the specific energy is still up to 42 Wh·kg^(-1).展开更多
Silicon/carbon composites are promising alternatives to current graphite anodes in commercial lithiumion batteries(LIBs)because of their high capacity and excellent safety.Nevertheless,the unsatisfactory fastcharging ...Silicon/carbon composites are promising alternatives to current graphite anodes in commercial lithiumion batteries(LIBs)because of their high capacity and excellent safety.Nevertheless,the unsatisfactory fastcharging capability and cycle stability of Si/C composites caused by slow charge transport capability and huge volume change under industrial electrode conditions severely hamper their development.Here,a novel Si/C anode was fabricated by homogeneously depositing amorphous C-Si nanolayers on graphite(C-Si@graphite).C-Si nanolayers with uniformly dispersed sub-nanometer Si particles in 3D carbon skeleton significantly boost electron and Li-ion transport and efficiently relieve Si's agglomeration and volume change.As a result,the tailored C-Si@graphite electrodes show an excellent rate capacity(760.3 mAh·g^(-1)at 5.0C)and long cycle life of over 1000 cycles at 1.0C and800 cycles at 2.0C under industrial electrode conditions.In addition,the assembled full cells(C-Si@graphite,anode;Li[Ni_(0.8)Co_(0.1)Mn_(0.1)]O_(2),cathode)present superior fastcharging capability(240.4 Wh·kg^(-1),charging for16.2 min,3.0C)and long cycle life(80.7%capacity retention after 500 cycles at 1.0C),demonstrating the massive potential of C-Si@graphite for practical application.展开更多
SiO-based materials represent a promising class of anodes for lithium-ion batteries(LIBs),with a high theoretical capacity and appropriate and safe Li-insertion potential.However,SiO experiences a large volume change ...SiO-based materials represent a promising class of anodes for lithium-ion batteries(LIBs),with a high theoretical capacity and appropriate and safe Li-insertion potential.However,SiO experiences a large volume change during the electrochemical reaction,low Li diffusivity,and low electron conductivity,resulting in degradation and low rate capability for LIBs.Here,we report on the rapid crafting of SiO–Sn_(2)Fe@C composites via a one-step plasma milling process,leading to an alloy of Sn and Fe and in turn refining SiO and Sn_(2)Fe into nanoparticles that are well dispersed in a nanosized,few-layer graphene matrix.The Sn and Fe nanoparticles generated during the first Li-insertion process form a stable network to improve Li diffusivity and electron conductivity.As an anode mate-rial,the SiO–Sn_(2)Fe@C composite manifests high reversible capacities,superior cycling stability,and excellent rate capability.The capacity retention is found to be as high as 95%and 84%at the 100th and 300th cycles under 0.3 C.During rate capability testing at 3,6,and 11 C,the capacity retentions are 71%,60%,and 50%,respectively.This study highlights that this simple,one-step plasma milling strategy can further improve SiO-based anode materials for high-performance LIBs.展开更多
With the increasing popularity of electric/hybrid vehicles and the rapid development of 3C electronics,there is a growing interest in high-rate energy storage systems.The rapid development and widespread adoption of l...With the increasing popularity of electric/hybrid vehicles and the rapid development of 3C electronics,there is a growing interest in high-rate energy storage systems.The rapid development and widespread adoption of lithiumion batteries(LIBs)can be attributed to their numerous advantages,including high energy density,high operating voltage,environmental friendliness,and lack of memory effect.However,the progress of LIBs is currently hindered by the limitations of energy storage materials,which serve as vital components.Therefore,there is an urgent need to address the development of a new generation of high-rate energy storage materials in order to overcome these limitations and further advance LIB technology.Niobium-based oxides have emerged as promising candidates for the fabrication of fast-charging Li-ion batteries due to their excellent rate capability and long lifespan.This review paper provides a comprehensive analysis of the fundamentals,methodologies,and electrochemistries of niobium-based oxides,with a specific focus on the evolution and creation of crystal phases of Nb_(2)O_(5),fundamental electrochemical behavior,and modification methods including morphology modulation,composite technology,and carbon coating.Furthermore,the review explores Nb_(2)O_(5)-derived compounds and related advanced characterization techniques.Finally,the challenges and issues in the development of niobiumbased oxides for high-rate energy storage batteries are discussed,along with future research perspectives.展开更多
Alloying-type metal sulfides with high sodiation activity and theoretical capacity are promising anode materials for high energy density sodium ion batteries.However,the large volume change and the migratory and aggre...Alloying-type metal sulfides with high sodiation activity and theoretical capacity are promising anode materials for high energy density sodium ion batteries.However,the large volume change and the migratory and aggregation behavior of metal atoms will cause severe capacity decay during the charge/discharge process.Herein,a robust and conductive TiS_(2)framework is integrated with a high-capacity SbS layer to construct a single phase(SbS)_(1.15)TiS_(2)superlattice for both high-capacity and fast Na^(+)storage.The metallic TiS_(2)sublayer with high electron activity acts as a robust and conductive skeleton to buffer the volume expansion caused by conversion and alloying reaction between Na+and SbS sublayer.Hence,high capacity and high rate capability can be synergistically realized in a single phase(SbS)_(1.15)TiS_(2)superlattice.The novel(SbS)_(1.15)TiS_(2)anode has a high charge capacity of 618 mAh g^(-1)at 0.2 C and superior rate performance and cycling stability(205 mAh g^(-1)at 35 C after 2,000 cycles).Furthermore,in situ and ex situ characterizations are applied to get an insight into the multi-step reaction mechanism.The integrity of robust Na-Ti-S skeleton during(dis)charge process can be confirmed.This superlattice construction idea to integrate the Na^(+)-active unit and electron-active unit would provide a new avenue for exploring high-performance anode materials for advanced sodium-ion batteries.展开更多
Solar power is mostly influenced by solar irradiation,weather conditions,solar array mismatches and partial shading conditions.Therefore,before installing solar arrays,it is necessary to simulate and determine the pos...Solar power is mostly influenced by solar irradiation,weather conditions,solar array mismatches and partial shading conditions.Therefore,before installing solar arrays,it is necessary to simulate and determine the possible power generated.Maximum power point tracking is needed in order to make sure that,at any time,the maximum power will be extracted from the photovoltaic system.However,maximum power point tracking is not a suitable solution for mismatches and partial shading conditions.To overcome the drawbacks of maximum power point tracking due to mismatches and shadows,distributed maximum power point tracking is util-ized in this paper.The solar farm can be distributed in different ways,including one DC-DC converter per group of modules or per module.In this paper,distributed maximum power point tracking per module is implemented,which has the highest efficiency.This technology is applied to electric vehicles(EVs)that can be charged with a Level 3 charging station in<1 hour.However,the problem is that charging an EV in<1 hour puts a lot of stress on the power grid,and there is not always enough peak power reserve in the existing power grid to charge EVs at that rate.Therefore,a Level 3(fast DC)EV charging station using a solar farm by implementing distributed maximum power point tracking is utilized to address this issue.Finally,the simulation result is reported using MATLAB®,LTSPICE and the System Advisor Model.Simulation results show that the proposed 1-MW solar system will provide 5 MWh of power each day,which is enough to fully charge~120 EVs each day.Additionally,the use of the proposed photovoltaic system benefits the environment by removing a huge amount of greenhouse gases and hazardous pollutants.For example,instead of supplying EVs with power from coal-fired power plants,1989 pounds of CO_(2) will be eliminated from the air per hour.展开更多
High-performance batteries are poised for electrification of vehicles and therefore mitigate greenhouse gas emissions,which,in turn,promote a sustainable future.However,the design of optimized batteries is challenging...High-performance batteries are poised for electrification of vehicles and therefore mitigate greenhouse gas emissions,which,in turn,promote a sustainable future.However,the design of optimized batteries is challenging due to the nonlinear governing physics and electrochemistry.Recent advancements have demonstrated the potential of deep learning techniques in efficiently designing batteries,particularly in optimizing electrodes and electrolytes.This review provides comprehensive concepts and principles of deep learning and its application in solving battery-related electrochemical problems,which bridges the gap between artificial intelligence and electrochemistry.We also examine the potential challenges and opportunities associated with different deep learning approaches,tailoring them to specific battery requirements.Ultimately,we aim to inspire future advancements in both fundamental scientific understanding and practical engineering in the field of battery technology.Furthermore,we highlight the potential challenges and opportunities for different deep learning methods according to the specific battery demand to inspire future advancement in fundamental science and practical engineering.展开更多
基金supported by the National Natural Science Foundation of China (No.92372123)the Natural Science Foundation of Guangdong Province (No.2022B1515020005)the Department of Science and Technology of Guangdong Province (No.2020B0101030005)
文摘Fast-charging and low temperature operation are of vital importance for the further development of lithium-ion batteries(LIBs),which is hindered by the utilization of conventional carbonate-based electrolytes due to their slow kinetics,narrow operating temperature and voltage range.Herein,an acetonitrile(AN)-based localized high-concentration electrolyte(LHCE)is proposed to retain liquid state and high ionic conductivity at ultra-low temperatures while possessing high oxidation stability.We originally reveal the excellent thermal shielding effect of non-solvating diluent to prevent the aggregation of Li^(+) solvates as temperature drops,maintaining the merits of fast Li transport and facile desolvation as at room temperature,which bestows the graphite electrode with remarkable low temperature performance(264 mA h g^(-1) at-20 C).Remarkably,an extremely high capacity retention of 97%is achieved for high-voltage high-energy graphite||NCM batteries after 250 cycles at-20 C,and a high capacity of 110 mA h g^(-1)(71%of its room-temperature capacity)is retained at-30°C.The study unveils the key role of the non-solvating diluents and provides instructive guidance in designing electrolytes towards fast-charging and low temperature LIBs.
基金supported by the National Key Research and Development Program of China(2022YFA1504100)the National Natural Science Foundation of China(22125903,51872283,and 22005298)+4 种基金Dalian Innovation Support Plan for High Level Talents(2019RT09)Dalian National Laboratory For Clean Energy(DNL),Chinese Academy of Sciences(CAS),DNL Cooperation Fund,CAS(DNL202016 and DNL202019)Dalian Institute of Chemical Physics(DICP I2020032)Exploratory Research Project of Yanchang Petroleum International Limited and DICP(yc-hw-2022ky-01)the Joint Fund of the Yulin University and the Dalian National Laboratory for Clean Energy(YLU-DNL Fund 2021002 and 2021009).
文摘Lithium-ion batteries(LIBs)with the“double-high”characteristics of high energy density and high power density are in urgent demand for facilitating the development of advanced portable electronics.However,the lithium ion(Li+)-storage performance of the most commercialized lithium cobalt oxide(LiCoO_(2),LCO)cathodes is still far from satisfactory in terms of high-voltage and fast-charging capabilities for reaching the double-high target.Herein,we systematically summarize and discuss high-voltage and fast-charging LCO cathodes,covering in depth the key fundamental challenges,latest advancements in modification strategies,and future perspectives in this field.Comprehensive and elaborated discussions are first presented on key fundamental challenges related to structural degradation,interfacial instability,the inhomogeneity reactions,and sluggish interfacial kinetics.We provide an instructive summary of deep insights into promising modification strategies and underlying mechanisms,categorized into element doping(Li-site,cobalt-/oxygen-site,and multi-site doping)for improved Li+diffusivity and bulkstructure stability;surface coating(dielectrics,ionic/electronic conductors,and their combination)for surface stability and conductivity;nanosizing;combinations of these strategies;and other strategies(i.e.,optimization of the electrolyte,binder,tortuosity of electrodes,charging protocols,and prelithiation methods).Finally,forward-looking perspectives and promising directions are sketched out and insightfully elucidated,providing constructive suggestions and instructions for designing and realizing high-voltage and fast-charging LCO cathodes for next-generation double-high LIBs.
文摘Recent technological advancements,such as portable electronics and electric vehicles,have created a pressing need for more efficient energy storage solutions.Lithium-ion batteries(LIBs)have been the preferred choice for these applications,with graphite being the standard anode material due to its stability.However,graphite falls short of meeting the growing demand for higher energy density,possessing a theoretical capacity that lags behind.To address this,researchers are actively seeking alternative materials to replace graphite in commercial batteries.One promising avenue involves lithiumalloying materials like silicon and phosphorus,which offer high theoretical capacities.Carbon-silicon composites have emerged as a viable option,showing improved capacity and performance over traditional graphite or pure silicon anodes.Yet,the existing methods for synthesizing these composites remain complex,energy-intensive,and costly,preventing widespread adoption.A groundbreaking approach is presented here:the use of a laser writing strategy to rapidly transform common organic carbon precursors and silicon blends into efficient“graphenic silicon”composite thin films.These films exhibit exceptional structural and energy storage properties.The resulting three-dimensional porous composite anodes showcase impressive attributes,including ultrahigh silicon content,remarkable cyclic stability(over 4500 cycles with∼40%retention),rapid charging rates(up to 10 A g^(-1)),substantial areal capacity(>5.1 mAh cm^(-2)),and excellent gravimetric capacity(>2400 mAh g^(-1) at 0.2 A g^(-1)).This strategy marks a significant step toward the scalable production of high-performance LIB materials.Leveraging widely available,cost-effective precursors,the laser-printed“graphenic silicon”composites demonstrate unparalleled performance,potentially streamlining anode production while maintaining exceptional capabilities.This innovation not only paves the way for advanced LIBs but also sets a precedent for transforming various materials into high-performing electrodes,promising reduced complexity and cost in battery production.
基金All authors acknowledge fund support from Guangdong Basic and Applied Basic Research Foundation(2020A1515110762)National Natural Science Foundation of China(52172084).
文摘Fabricating low-strain and fast-charging silicon-carbon composite anodes is highly desired but remains a huge challenge for lithium-ion batteries.Herein,we report a unique silicon-carbon composite fabricated by uniformly dis-persing amorphous Si nanodots(SiNDs)in carbon nanospheres(SiNDs/C)that are welded on the wall of the macroporous carbon framework(MPCF)by vertical graphene(VG),labeled as MPCF@VG@SiNDs/C.The high dispersity and amor-phous features of ultrasmall SiNDs(~0.7 nm),the flexible and directed electron/Li+transport channels of VG,and the MPCF impart the MPCF@VG@SiNDs/C more lithium storage sites,rapid Li+transport path,and unique low-strain property during Li+storage.Consequently,the MPCF@VG@SiNDs/C exhibits high cycle stability(1301.4 mAh g^(-1) at 1 A g^(-1) after 1000 cycles without apparent decay)and high rate capacity(910.3 mAh g^(-1),20 A g^(-1))in half cells based on industrial electrode standards.The assembled pouch full cell delivers a high energy density(1694.0 Wh L^(-1);602.8 Wh kg^(-1))and an excellent fast-charging capability(498.5 Wh kg^(-1),charging for 16.8 min at 3 C).This study opens new possibilities for preparing advanced silicon-carbon com-posite anodes for practical applications.
基金the support by the National Natural Science Foundation of China(52072137 and 52272207)。
文摘Lithium-ion batteries(LIBs)with fast-charging capability are essential for enhancing consumer experience and accelerating the global market adoption of electric vehicles.However,achieving fast-charging capability without compromising energy density,cycling lifespan,and safety of LIBs remains a significant challenge due to the formation of dendritic Li metal on graphite anode under fast charging condition.In view of this,the fundamentals for the dendritic metallic Li formation and the strategies for suppressing metallic Li plating based on analyzing the entire Li^(+)transport pathway at the anode including electrolyte,pore structure of electrode,and surface and bulk of materials are summarized and discussed in this review.Besides,we highlight the importance of designing thick electrodes with fast Li^(+)transport kinetics and comprehensively understanding the interaction between solid electrolyte interphase(SEI)and Li^(+)migration in order to avoid the formation of dendritic Li metal in practical fast-charging batteries.Finally,the regulation of Li metal plating with plane morphology,instead of dendritic structure,on the surface of graphite electrode under fast-charging condition is analyzed as a future direction to achieve higher energy density of batteries without safety concerns.
基金supported by the National Key Research and Development Project(2018YFE0124800)the National Nature Science Foundation of China(51702157,51873086,51673096).
文摘High-energy–density lithium-ion batteries(LIBs)that can be safely fast-charged are desirable for electric vehicles.However,sub-optimal lithiation potential and low capacity of commonly used LIBs anode cause safety issues and low energy density.Here we hypothesize that a cobalt vanadate oxide,Co_(2)VO_(4),can be attractive anode material for fast-charging LIBs due to its high capacity(~1000 mAh g^(−1))and safe lithiation potential(~0.65 V vs.Li^(+)/Li).The Li+diffusion coefficient of Co2VO4 is evaluated by theoretical calculation to be as high as 3.15×10^(-10) cm^(2) s^(−1),proving Co_(2)VO_(4) a promising anode in fast-charging LIBs.A hexagonal porous Co2VO4 nanodisk(PCVO ND)structure is designed accordingly,featuring a high specific surface area of 74.57 m^(2) g^(−1) and numerous pores with a pore size of 14 nm.This unique structure succeeds in enhancing Li^(+) and electron transfer,leading to superior fast-charging performance than current commercial anodes.As a result,the PCVO ND shows a high initial reversible capacity of 911.0 mAh g^(−1) at 0.4 C,excellent fast-charging capacity(344.3 mAh g^(−1) at 10 C for 1000 cycles),outstanding long-term cycling stability(only 0.024% capacity loss per cycle at 10 C for 1000 cycles),confirming the commercial feasibility of PCVO ND in fast-charging LIBs.
基金supported by the National Key Research and Development Program(2019YFC0810703)the National Natural Science Foundation of China(22071133)the China Postdoctoral Science Foundation(2020M680581)。
文摘With the ever-growing application of lithium-ion batteries(LIBs), their fast-charging technology has attracted great interests of scientists. However, growth of lithium dendrites during fast charge of the bat teries with high energy density may pose great threats to the operation and cause serious safety issues Herein, we prepared a functional separator with an ultra-thin(20 nm) layer of Au nanoparticles deposited by evaporation coating method which could regulate growth direction and morphology of the lithium dendrites, owing to nearly zero overpotential of lithium meal nucleation on lithiated Au. Once the Li den drites are about to form on the graphite anode during fast charging(or lithiation), they plate predomi nantly on the Au deposited separator rather than on the graphite. Such selective deposition does no compromise the electrochemical performance of batteries under normal cycling. More importantly, i enables the better cycling stability of batteries at fast charge condition. The Li/Graphite cells with Au nanoparticles coated separator could cycle stably with a high areal capacity retention of 90.5% over 95 cycles at the current density of 0.72 m A cm^(-2). The functional separator provides an effective strategy to adjust lithium plating position at fast charge to ensure high safety of batteries without a compromise on the energy density of LIBs.
基金supported by the National Natural Science Foundation of China(NSFC No.52172257 and 22005334)the Natural Science Foundation of Beijing(Grant No.Z200013)the National Key Research and Development Program of China(Grant No.2022YFB2502200).
文摘Fast-charging lithium-ion batteries are highly required,especially in reducing the mileage anxiety of the widespread electric vehicles.One of the biggest bottlenecks lies in the sluggish kinetics of the Li^(+)intercalation into the graphite anode;slow intercalation will lead to lithium metal plating,severe side reactions,and safety concerns.The premise to solve these problems is to fully understand the reaction pathways and rate-determining steps of graphite during fast Li^(+)intercalation.Herein,we compare the Li^(+)diffusion through the graphite particle,interface,and electrode,uncover the structure of the lithiated graphite at high current densities,and correlate them with the reaction kinetics and electrochemical performances.It is found that the rate-determining steps are highly dependent on the particle size,interphase property,and electrode configuration.Insufficient Li^(+)diffusion leads to high polarization,incomplete intercalation,and the coexistence of several staging structures.Interfacial Li^(+)diffusion and electrode transportation are the main rate-determining steps if the particle size is less than 10μm.The former is highly dependent on the electrolyte chemistry and can be enhanced by constructing a fluorinated interphase.Our findings enrich the understanding of the graphite structural evolution during rapid Li^(+)intercalation,decipher the bottleneck for the sluggish reaction kinetics,and provide strategic guidelines to boost the fast-charging performance of graphite anode.
基金financially supported by Shenzhen Key Laboratory of Advanced Energy Storage(No.ZDSYS20220401141000001)the Research Grants Council of the Hong Kong Special Administrative Region,China(Project No.R6005-20)。
文摘High theoretical capacity and unique layered structures make MoS_(2)a promising lithium-ion battery anode material.However,the anisotropic ion transport in layered structures and the poor intrinsic conductivity of MoS_(2)lead to unacceptable ion transport capability.Here,we propose in-situ construction of interlayer electrostatic repulsion caused by Co^(2+)substituting Mo^(4+)between MoS_(2)layers,which can break the limitation of interlayer van der Waals forces to fabricate monolayer MoS_(2),thus establishing isotropic ion transport paths.Simultaneously,the doped Co atoms change the electronic structure of monolayer MoS_(2),thus improving its intrinsic conductivity.Importantly,the doped Co atoms can be converted into Co nanoparticles to create a space charge region to accelerate ion transport.Hence,the Co-doped monolayer MoS_(2)shows ultrafast lithium ion transport capability in half/full cells.This work presents a novel route for the preparation of monolayer MoS_(2)and demonstrates its potential for application in fast-charging lithium-ion batteries.
基金the support from the China Scholarship Council(202006370035 and 202006220024)the Otto M?nsted Fond(22-70-1620)。
文摘Fast charging is considered a promising protocol for raising the charging efficiency of electric vehicles.However,high currents applied to Lithium-ion(Li-ion)batteries inevitably accelerate the degradation and shorten their lifetime.This work designs a multi-step fast-charging method to extend the lifetime of LiNi0.5Co0.2Mn0.3O2(NMC)/graphite Li-ion batteries based on the studies of half cells and investigates the aging mechanisms for different charging methods.The degradation has been studied from both full cell behaviour and materials perspectives through a combination of non-destructive diagnostic methods and post-mortem analysis.In the proposed multi-step charging protocol,the state-of-charge(SOC)profile is subdivided into five ranges,and the charging current is set differently for different SOC ranges.One of the designed multi-step fast charging protocols is shown to allow for a 200 full equivalent cycles longer lifetime as compared to the standard charging method,while the charging time is reduced by 20%.From the incremental capacity analysis and electrical impedance spectroscopy,the loss of active materials and lithium inventory on the electrodes,as well as an increase in internal resistance for the designed multistep constant-current-constant-voltage(MCCCV)protocol have been found to be significantly lower than for the standard charging method.Post-mortem analysis shows that cells aged by the designed MCCCV fast charging protocol exhibit less graphite exfoliation and crystallization damage,as well as a reduced solid electrolyte interphase(SEI)layer growth on the anode,leading to a lower Rseiresistance and extended lifetime.
基金supported by the National Natural Science Foundation of China(22125903,51872283,and 22005298)the National Key R&D Program of China(2022YFA1504100 and 2023YFB4005204)+3 种基金Dalian Innovation Support Plan for High Level Talents(2019RT09)Dalian Institute of Chemical Physics(DICP I2020032)The Joint Fund of the Yulin University and the Dalian National Laboratory for Clean Energy(YLU-DNL Fund 2021002,YLU-DNL Fund 2021009)Exploratory Research Project of Yanchang Petroleum International Limited and DICP(yc-hw-2022ky-01).
文摘High-voltage and fast-charging LiCoO_(2)(LCO)is key to high-energy/power-density Li-ion batteries.However,unstable surface structure and unfavorable electronic/ionic conductivity severely hinder its high-voltage fast-charging cyclability.Here,we construct a Li/Na-B-Mg-Si-O-F-rich mixed ion/electron interface network on the 4.65 V LCO electrode to enhance its rate capability and long-term cycling stability.Specifically,the resulting artificial hybrid conductive network enhances the reversible conversion of Co^(3+)/^(4+)/O_(2)/nredox by the interfacial ion–electron cooperation and suppresses interface side reactions,inducing an ultrathin yet compact cathode electrolyte interphase.Simultaneously,the derived near-surface Na+/Mg2+/Si^(4+)-pillared local intercalation structure greatly promotes the Li^(+)diffusion around the 4.55 V phase transition and stabilizes the cathode interface.Finally,excellent 3 C(1 C=274 mA g1)fast charging performance is demonstrated with 73.8%capacity retention over 1000 cycles.Our findings shed new insights to the fundamental mechanism of interfacial ion/electron synergy in stabilizing and enhancing fast-charging cathode materials.
基金the National Nature Science Foundation of China(grant nos.52072222 and 22279073)the National Key Research and Development Project of China(grant no.2022YFA1200044)+2 种基金the Taishan Scholar Project of Shandong Province of China(grant no.62460082061017)the Natural Science Foundation of Shandong Province(grant no.ZR2022ZD35)the National Nature Science Foundation of China(grant nos.21790050 and 21790051).
文摘The sluggish lithium-ion(Li-ion)transport kinetics in graphite anode hinders its application in fast-charging Li-ion batteries(LIBs).Here,we develop an ionpumping interphase(IPI)on graphdiyne(GDY)/graphite heterojunction anodes to boost the ionic transport kinetics and enable high-performance,fast-charging LIBs.The IPI changed the ion solvation/desolvation environment by covalent/non-covalent interactions with Li ions or solvents to optimize solid-electrolyte interphase(SEI)and regulate Li-ion transport behavior.We studied the in situ growth of few-layer GDY on graphite surface(GDY/graphite)as the IPI and found that the strong interaction between GDY and Li ions enabled surface-induced modification of the ion solvation behavior and surface-assisted desolvation effect to accelerate the Li-ion desolvation process.A functional anion-derived SEI layer with improved Li-ion conductivity was created.Together with the generated built-in electric field at GDY/graphite hetero-interface self-pumping Li ions to intercalate into the graphite,the Li-ion transport kinetics was significantly enhanced to effectively eliminate Li plating and large voltage polarization of the graphite anodes.A fast Li intercalation in GDY/graphite without Li oversaturation at the edge of the graphite was directly observed.The superior performance with high capacity(139.2 mA h g^(-1))and long lifespan(1650 cycles)under extremely fast-charging conditions(20 C,1 C=372 mA g^(-1))was achieved on GDY/graphite anodes.Even at low temperatures(-20℃),a specific capacity of 128.4 mA h g^(-1) was achieved with a capacity retention of 80%after 500 cycles at a 2 C rate.
基金This work was supported by the Program for Huazhong University of Science and Technology(HUST)Academic Frontier Youth Team(2017QYTD04)the Program for HUST Graduate Innovation and Entrepreneurship Fund(2019YGSCXCY037)+2 种基金Authors acknowledge Grant DMETKF2018019 by State Key Laboratory of Digital Manufacturing Equipment and Technology,Huazhong University of Science and TechnologyThis study was also financially supported by the Guangdong Science and Technology Project(2016B020240001)the Guangdong Natural Science Foundation(2018A030310150).
文摘Efficient fast-charging technology is necessary for the extension of the driving range of electric vehicles.However,lithium-ion cells generate immense heat at high-current charging rates.In order to address this problem,an efficient fast charging–cooling scheduling method is urgently needed.In this study,a liquid cooling-based thermal management system equipped with mini-channels was designed for the fastcharging process of a lithium-ion battery module.A neural network-based regression model was proposed based on 81 sets of experimental data,which consisted of three sub-models and considered three outputs:maximum temperature,temperature standard deviation,and energy consumption.Each sub-model had a desirable testing accuracy(99.353%,97.332%,and 98.381%)after training.The regression model was employed to predict all three outputs among a full dataset,which combined different charging current rates(0.5C,1C,1.5C,2C,and 2.5C(1C=5 A))at three different charging stages,and a range of coolant rates(0.0006,0.0012,and 0.0018 kg·s^(-1)).An optimal charging–cooling schedule was selected from the predicted dataset and was validated by the experiments.The results indicated that the battery module’s state of charge value increased by 0.5 after 15 min,with an energy consumption lower than 0.02 J.The maximum temperature and temperature standard deviation could be controlled within 33.35 and 0.8C,respectively.The approach described herein can be used by the electric vehicles industry in real fast-charging conditions.Moreover,optimal fast charging-cooling schedule can be predicted based on the experimental data obtained,that in turn,can significantly improve the efficiency of the charging process design as well as control energy consumption during cooling.
基金financially supported by the National Natural Science Foundation of China(No.22279122)Zhejiang Provincial Natural Science Foundation of China(No.LZ22B030004)the Foundation of State Key Laboratory of Coal Conversion(No.J22-23-909)。
文摘Hybrid Na-ion capacitors(NICs)have received considerable interests owing to their low-cost,high-safety,and rapidly charging energy-storage characteristics.The NICs are composed of a capacitor-type cathode and a battery-type anode.The major challenge for NICs is to search for suitable electrode materials to overcome the sluggish diffusion of Na^(+)in the anode.Herein,ultrafine vanadium sulfide is encapsulated in carbon fiber(V_(3)S_(4)@CNF)as a self-supported electrode by electrospinning and in situ sulfurization.The carbon cladding and one-dimensional(ID)nanofiber network-like structure could alleviate the volume expansion of V_(3)S_(4)during Na^(+)de-/intercalation process.Consequently,the V_(3)S_(4)@CNF anode exhibited a pseudocapacitive sodium storage in terms of large Na^(+)-storage capacity(476 mAh·g^(-1)at 0.1A·g^(-1)),high-rate capability(290 mAh·g^(-1)at 20.0 A·g^(-1))and excellent cycling stability(95%capacity retention for1500 cycles at 2.0 A·g^(-1))in Na half-cells.By employing V_(3)S_(4)@CNF as the anode and the activated carbon(AC)cathode,the as-assembled NICs could deliver a high energy density of 110 Wh·kg^(-1)at a power density of200 W·kg^(-1).Even at a high power of 10,000 W·kg^(-1),the specific energy is still up to 42 Wh·kg^(-1).
基金financially supported by Guangdong Basic and Applied Basic Research Foundation (No.2020A1515110762)。
文摘Silicon/carbon composites are promising alternatives to current graphite anodes in commercial lithiumion batteries(LIBs)because of their high capacity and excellent safety.Nevertheless,the unsatisfactory fastcharging capability and cycle stability of Si/C composites caused by slow charge transport capability and huge volume change under industrial electrode conditions severely hamper their development.Here,a novel Si/C anode was fabricated by homogeneously depositing amorphous C-Si nanolayers on graphite(C-Si@graphite).C-Si nanolayers with uniformly dispersed sub-nanometer Si particles in 3D carbon skeleton significantly boost electron and Li-ion transport and efficiently relieve Si's agglomeration and volume change.As a result,the tailored C-Si@graphite electrodes show an excellent rate capacity(760.3 mAh·g^(-1)at 5.0C)and long cycle life of over 1000 cycles at 1.0C and800 cycles at 2.0C under industrial electrode conditions.In addition,the assembled full cells(C-Si@graphite,anode;Li[Ni_(0.8)Co_(0.1)Mn_(0.1)]O_(2),cathode)present superior fastcharging capability(240.4 Wh·kg^(-1),charging for16.2 min,3.0C)and long cycle life(80.7%capacity retention after 500 cycles at 1.0C),demonstrating the massive potential of C-Si@graphite for practical application.
基金This work was supported by the National Natural Science Foundation of China(grant numbers 52001124,52071144,51831009,and 51621001).
文摘SiO-based materials represent a promising class of anodes for lithium-ion batteries(LIBs),with a high theoretical capacity and appropriate and safe Li-insertion potential.However,SiO experiences a large volume change during the electrochemical reaction,low Li diffusivity,and low electron conductivity,resulting in degradation and low rate capability for LIBs.Here,we report on the rapid crafting of SiO–Sn_(2)Fe@C composites via a one-step plasma milling process,leading to an alloy of Sn and Fe and in turn refining SiO and Sn_(2)Fe into nanoparticles that are well dispersed in a nanosized,few-layer graphene matrix.The Sn and Fe nanoparticles generated during the first Li-insertion process form a stable network to improve Li diffusivity and electron conductivity.As an anode mate-rial,the SiO–Sn_(2)Fe@C composite manifests high reversible capacities,superior cycling stability,and excellent rate capability.The capacity retention is found to be as high as 95%and 84%at the 100th and 300th cycles under 0.3 C.During rate capability testing at 3,6,and 11 C,the capacity retentions are 71%,60%,and 50%,respectively.This study highlights that this simple,one-step plasma milling strategy can further improve SiO-based anode materials for high-performance LIBs.
基金This work was financially supported by“Hundred Young Talents Program”(No.263113491)from Guangdong University of Technology.
文摘With the increasing popularity of electric/hybrid vehicles and the rapid development of 3C electronics,there is a growing interest in high-rate energy storage systems.The rapid development and widespread adoption of lithiumion batteries(LIBs)can be attributed to their numerous advantages,including high energy density,high operating voltage,environmental friendliness,and lack of memory effect.However,the progress of LIBs is currently hindered by the limitations of energy storage materials,which serve as vital components.Therefore,there is an urgent need to address the development of a new generation of high-rate energy storage materials in order to overcome these limitations and further advance LIB technology.Niobium-based oxides have emerged as promising candidates for the fabrication of fast-charging Li-ion batteries due to their excellent rate capability and long lifespan.This review paper provides a comprehensive analysis of the fundamentals,methodologies,and electrochemistries of niobium-based oxides,with a specific focus on the evolution and creation of crystal phases of Nb_(2)O_(5),fundamental electrochemical behavior,and modification methods including morphology modulation,composite technology,and carbon coating.Furthermore,the review explores Nb_(2)O_(5)-derived compounds and related advanced characterization techniques.Finally,the challenges and issues in the development of niobiumbased oxides for high-rate energy storage batteries are discussed,along with future research perspectives.
基金supported by the National Key Research and Development Program of China(2019YFA0210600)the National Natural Science Foundation of China(51922103 and 51972326)。
文摘Alloying-type metal sulfides with high sodiation activity and theoretical capacity are promising anode materials for high energy density sodium ion batteries.However,the large volume change and the migratory and aggregation behavior of metal atoms will cause severe capacity decay during the charge/discharge process.Herein,a robust and conductive TiS_(2)framework is integrated with a high-capacity SbS layer to construct a single phase(SbS)_(1.15)TiS_(2)superlattice for both high-capacity and fast Na^(+)storage.The metallic TiS_(2)sublayer with high electron activity acts as a robust and conductive skeleton to buffer the volume expansion caused by conversion and alloying reaction between Na+and SbS sublayer.Hence,high capacity and high rate capability can be synergistically realized in a single phase(SbS)_(1.15)TiS_(2)superlattice.The novel(SbS)_(1.15)TiS_(2)anode has a high charge capacity of 618 mAh g^(-1)at 0.2 C and superior rate performance and cycling stability(205 mAh g^(-1)at 35 C after 2,000 cycles).Furthermore,in situ and ex situ characterizations are applied to get an insight into the multi-step reaction mechanism.The integrity of robust Na-Ti-S skeleton during(dis)charge process can be confirmed.This superlattice construction idea to integrate the Na^(+)-active unit and electron-active unit would provide a new avenue for exploring high-performance anode materials for advanced sodium-ion batteries.
基金support of the National Science Foundation(NSF)under Award Number:2115427 is gratefully acknowledged.SRS RN:Sustainable Transportation Electrification for an Equitable and Resilient Society(STEERS).
文摘Solar power is mostly influenced by solar irradiation,weather conditions,solar array mismatches and partial shading conditions.Therefore,before installing solar arrays,it is necessary to simulate and determine the possible power generated.Maximum power point tracking is needed in order to make sure that,at any time,the maximum power will be extracted from the photovoltaic system.However,maximum power point tracking is not a suitable solution for mismatches and partial shading conditions.To overcome the drawbacks of maximum power point tracking due to mismatches and shadows,distributed maximum power point tracking is util-ized in this paper.The solar farm can be distributed in different ways,including one DC-DC converter per group of modules or per module.In this paper,distributed maximum power point tracking per module is implemented,which has the highest efficiency.This technology is applied to electric vehicles(EVs)that can be charged with a Level 3 charging station in<1 hour.However,the problem is that charging an EV in<1 hour puts a lot of stress on the power grid,and there is not always enough peak power reserve in the existing power grid to charge EVs at that rate.Therefore,a Level 3(fast DC)EV charging station using a solar farm by implementing distributed maximum power point tracking is utilized to address this issue.Finally,the simulation result is reported using MATLAB®,LTSPICE and the System Advisor Model.Simulation results show that the proposed 1-MW solar system will provide 5 MWh of power each day,which is enough to fully charge~120 EVs each day.Additionally,the use of the proposed photovoltaic system benefits the environment by removing a huge amount of greenhouse gases and hazardous pollutants.For example,instead of supplying EVs with power from coal-fired power plants,1989 pounds of CO_(2) will be eliminated from the air per hour.
文摘High-performance batteries are poised for electrification of vehicles and therefore mitigate greenhouse gas emissions,which,in turn,promote a sustainable future.However,the design of optimized batteries is challenging due to the nonlinear governing physics and electrochemistry.Recent advancements have demonstrated the potential of deep learning techniques in efficiently designing batteries,particularly in optimizing electrodes and electrolytes.This review provides comprehensive concepts and principles of deep learning and its application in solving battery-related electrochemical problems,which bridges the gap between artificial intelligence and electrochemistry.We also examine the potential challenges and opportunities associated with different deep learning approaches,tailoring them to specific battery requirements.Ultimately,we aim to inspire future advancements in both fundamental scientific understanding and practical engineering in the field of battery technology.Furthermore,we highlight the potential challenges and opportunities for different deep learning methods according to the specific battery demand to inspire future advancement in fundamental science and practical engineering.