The growing demands for energy storage systems,electric vehicles,and portable electronics have significantly pushed forward the need for safe and reliable lithium batteries.It is essential to design functional separat...The growing demands for energy storage systems,electric vehicles,and portable electronics have significantly pushed forward the need for safe and reliable lithium batteries.It is essential to design functional separators with improved mechanical and electrochemical characteristics.This review covers the improved mechanical and electrochemical performances as well as the advancements made in the design of separators utilizing a variety of techniques.In terms of electrolyte wettability and adhesion of the coating materials,we provide an overview of the current status of research on coated separators,in situ modified separators,and grafting modified separators,and elaborate additional performance parameters of interest.The characteristics of inorganics coated separators,organic framework coated separators and inorganic-organic coated separators from different fabrication methods are compared.Future directions regarding new modified materials,manufacturing process,quantitative analysis of adhesion and so on are proposed toward next-generation advanced lithium batteries.展开更多
Zinc-based batteries have attracted widespread attention due to their inherent safety,notable cost-effectiveness and consistent performance,etc.However,the advancement of zinc-based battery technology encounters signi...Zinc-based batteries have attracted widespread attention due to their inherent safety,notable cost-effectiveness and consistent performance,etc.However,the advancement of zinc-based battery technology encounters significant challenges,including the formation of zinc dendrites and irreversible side reactions.Separators are vital in batteries due to their role in preventing electrode contact and facilitating rapid movement of ions within the electrolyte.The incorporation of cellulose in batteries enables uniform ion transport and a stable electricfield,attributed to its excellent hydrophilicity,strong mechanical strength,and abundant active sites.Herein,the latest research progress of cellulose-based separators on various zinc-based batteries is systematically summarized.To begin with,the accomplishments and inherent limitations of traditional sep-arators are clarified.Next,it underscores the advantages of cellulose-based materials in battery technology,thoroughly examining their utilization and merits as separators in zinc-based batteries.Lastly,the review offers prospective insights into the future trajectory of cellulose-based separators in zinc-based batteries.Through a comprehensive analysis of the present landscape,the review establishes a framework for the future design and enhancement of cellulose-based separators,thereby fostering the progression of associated industries.展开更多
Separators in supercapacitors(SCs)frequently suffer from high resistance and the risk of short circuits due to inadequate electrolyte wettability,depressed mechanical properties,and insufficient thermal stability.Here...Separators in supercapacitors(SCs)frequently suffer from high resistance and the risk of short circuits due to inadequate electrolyte wettability,depressed mechanical properties,and insufficient thermal stability.Here,we develop a high-performance regenerated cellulose separator with nano-cracked structures for SCs via a binary solvent of superbase-derived ionic liquid and dimethylsulfoxide(DMSO).The unique nano-cracks with an average width of 7.45 nm arise from the acceleration of cellulose molecular reassembly by DMSO-regulated hydrogen bonding,which endows the separator with high porosity(70.2%)and excellent electrolyte retention(329%).The outstanding thermal stability(273℃)and mechanical strength(70 MPa)enable the separator to maintain its structural integrity under high temperatures and external forces.With these benefits,the SC utilizing the cellulose separator enables a high specific capacitance of 93.6 F g^(−1) at 1.0 A g^(−1) and a remarkable capacitance retention of 99.5%after 10,000 cycles compared with the commercial NKK-MPF30AC and NKK-TF4030.The robust and high-wettability cellulose separator holds promise as a superior alternative to commercial separators for advanced SCs with enhanced performance and improved safety.展开更多
The uneven deposition and high reactivity of lithium-metal anode(LMA)lead to uncontrollable dendrite growth,low Coulombic efficiency,and safety concerns,hindering their commercialization.Here,a representative polar-ri...The uneven deposition and high reactivity of lithium-metal anode(LMA)lead to uncontrollable dendrite growth,low Coulombic efficiency,and safety concerns,hindering their commercialization.Here,a representative polar-rich-group triazine-based covalent organic framework(COF-TzDha)with a desolvation effect is designed as an interlayer for stable,dendrite-free LMA.The abundant triazine rings in COFTzDha as a donor effectively attract lithium ions,while the one-dimensional nanopore structure facilitates lithium-ion migration.The periodic arrangement of polar groups(-OH)in the backbone interacts with electrolyte components(DOL,DME,TFSI-)to form a hydrogen bonding network that slows solvent molecules transport.Therefore,COF-TzDha effectively desolvates lithium ions from the solvent sheath,promoting uniform lithium ion flux and Li plating/stripping.Theoretical calculations verify that COFTzDha with abundant adsorption sites and strong adsorption energy facilitates lithium ion desolvation.Consequently,the introduction of COF-TzDha obtains a high ion mobility(0.75).The Li|COF@PP|Li symmetric cell cycles stably for over 1200 h at 4 mA cm^(-2)/4.0 mA h cm^(-2).The Li|COF@PP|LiFePO_(4)full cell also displays highly stable cycling performance with 600 cycles(75.5%capacity retention,~100% Coulombic efficiency)at 1 C.This work verifies an effective strategy for inducing uniform Li deposition and achieving dendrite-free,stable LMA using a polar-rich-group COF interlayer with a desolvation effect.展开更多
The thermal stability of lithium-ion battery separators is a critical determinant of battery safety and performance,especially in the context of rapidly expanding applications in electric vehicles and energy storage s...The thermal stability of lithium-ion battery separators is a critical determinant of battery safety and performance,especially in the context of rapidly expanding applications in electric vehicles and energy storage systems.While traditional polyolefin separators(PP/PE)dominate the market due to their cost-effectiveness and mechanical robustness,their inherent poor thermal stability poses significant safety risks under high-temperature conditions.This review provides a comprehensive analysis of recent advancements in enhancing separator thermal stability through coating materials(metal,ceramic,inorganic)and novel high-temperature-resistant polymers(e.g.,PVDF copolymers,PI,PAN).Notably,we critically evaluate the trade-offs between thermal resilience and electrochemical performance,such as the unintended increase in electronic conductivity from metal coatings(e.g.,Cu,MOFs)and reduced electrolyte wettability in ceramic coatings(e.g.,Al_(2)O_(3)).Innovations in hybrid coatings(e.g.,BN/PAN composites,gradient-structured MOFs)and scalable manufacturing techniques(e.g.,roll-to-roll electrospinning)are highlighted as promising strategies to balance these competing demands.Furthermore,a comparative analysis of next-generation high-temperature-resistant separators underscores their ionic conductivity,mechanical strength,and scalability,offering actionable insights for material selection.The review concludes with forward-looking perspectives on integrating machine learning for material discovery,optimizing interfacial adhesion in ceramic coatings,and advancing semi-/all-solid-state batteries to address both thermal and electrochemical challenges.This work aims to bridge the gap between laboratory innovations and industrial applications,fostering safer and more efficient lithium battery technologies.展开更多
Lithium-sulfur(Li-S)batteries with high energy density and capacity have garnered significant research attention among various energy storage devices.However,the shuttle effect of polysulfides(LiPSs)remains a major ch...Lithium-sulfur(Li-S)batteries with high energy density and capacity have garnered significant research attention among various energy storage devices.However,the shuttle effect of polysulfides(LiPSs)remains a major challenge for their practical application.The design of battery separators has become a key aspect in addressing the challenge.MXenes,a promising two-dimensional(2D)material,offer exceptional conductivity,large surface area,high mechanical strength,and active sites for surface reactions.When assembled into layered films,MXenes form highly tunable two-dimensional channels ranging from a few angstroms to over 1 nm.These nanoconfined channels are instrumental in facilitating lithium-ion transport while effectively impeding the shuttle effect of LiPSs,which are essential for improving the specific capacity and cyclic stability of Li-S batteries.Substantial progress has been made in developing MXenes-based separators for Li-S batteries,yet there remains a research gap in summarizing advancements from the perspective of interlayer engineering.This entails maintaining the 2D nanochannels of layered MXenes-based separators while modulating the physicochemical environment within the MXenes interlayers through targeted modifications.This review highlights advancements in in situ modification of MXenes and their integration with 0D,1D,and 2D materials to construct laminated nanocomposite separators for Li-S batteries.The future development directions of MXenes-based materials in Li-S energy storage devices are also outlined,to drive further advancements in MXenes for Li-S battery separators.展开更多
There are some inherent defects for the polyolefin based lithium battery separator,such as,poor thermal stability,poor electrolyte wettability and low porosity,which limit the development of lithium battery.An importa...There are some inherent defects for the polyolefin based lithium battery separator,such as,poor thermal stability,poor electrolyte wettability and low porosity,which limit the development of lithium battery.An important way to improve the performance of lithium battery is to improve the separator.Here,three novel separators combined with metal-organic framework materials(MOFs)and carbon materials were prepared by using the in situ growth method and the adsorption combination method simultaneously.The result showed that compared with the polypropylene separator,the porosity and electrolyte wettability were significantly improved in view of these novel polypropylene separators combined with MOFs and carbon materials.Meanwhile,the electrochemical performance of lithium battery equipped with the polypropylene separator combined with MOFs materials and carbon materials was also improved.The result showed that lithium batteries equipped with polypropylene separator combined with MOFs and carbon materials had higher capacity in the first charge and discharge cycle and better electrochemical kinetic reaction processes.展开更多
Due to the limitations of the raw materials and processes involved,polyolefin separators used in commercial lithium-ion batteries(LIBs)have gradually failed to meet the increasing requirements of high-end batteries in...Due to the limitations of the raw materials and processes involved,polyolefin separators used in commercial lithium-ion batteries(LIBs)have gradually failed to meet the increasing requirements of high-end batteries in terms of energy density,power density,and safety.Hence,it is very important to develop next-generation separators for advanced lithium(Li)-based recharge-able batteries including LIBs and Li-S batteries.Nonwoven nanofiber membranes fabricated via electrospinning technology are highly attractive candidates for high-end separators due to their simple processes,low-cost equipment,controllable microporous structure,wide material applicability,and availability of multiple functions.In this review,the electrospinning technologies for separators are reviewed in terms of devices,process and environment,and polymer solution systems.Furthermore,strategies toward the improvement of electrospun separators in advanced LIBs and Li-S batteries are presented in terms of the compositions and the structure of nanofibers and separators.Finally,the challenges and prospects of electrospun separators in both academia and industry are proposed.We anticipate that these systematic discussions can provide information in terms of commercial applications of electrospun separators and offer new perspectives for the design of functional electrospun separators for advanced Li-based batteries.展开更多
Lithium-sulfur(Li-S) batteries have generated significant attention due to their high theoretical specific capacity and energy density among a host of energy storage power devices.Nevertheless,the lithium polysulfide ...Lithium-sulfur(Li-S) batteries have generated significant attention due to their high theoretical specific capacity and energy density among a host of energy storage power devices.Nevertheless,the lithium polysulfide dissolution shuttle that occurs within Li-S batteries will lead to capacity deterioration and inadequate cycling stability.In the paper,we proposed a measure to deal with the above problems by modifying the separator with Nd_(2)O_(3)/graphene composite in Li-S batteries.Graphene's special chemical properties and structural qualities make it an excellent choice for Li-S batteries.Meanwhile,Nd_(2)O_(3) has a strong binding affinity with lithium polysulfide due to its low electronegativity,which exhibits Lewis' s acidity and forms strong interactions with lithium polysulfide,which is strongly Lewis basic.By utilizing these advantageous properties,Li-S batteries assembling Nd_(2)O_(3)-decorated reduced graphite oxide modified polypropylene separators(Nd_(2)O_(3)/RGO/PP) demonstrate outstanding electrochemical performance,including a mere 0.0525% capacity attenuation rate under 2C during 1000 cycles and with exceptional rate performance of 614 mAh/g even at 3C.This study presents valuable knowledge for effectively modifying separators using rare earth oxides to incorporate graphene,ultimately promoting the practical application of Li-S batteries.展开更多
Aqueous zinc-ion batteries(AZIBs)are one of the promising energy storage systems,which consist of electrode materials,electrolyte,and separator.The first two have been significantly received ample development,while th...Aqueous zinc-ion batteries(AZIBs)are one of the promising energy storage systems,which consist of electrode materials,electrolyte,and separator.The first two have been significantly received ample development,while the prominent role of the separators in manipulating the stability of the electrode has not attracted sufficient attention.In this work,a separator(UiO-66-GF)modified by Zr-based metal organic framework for robust AZIBs is proposed.UiO-66-GF effectively enhances the transport ability of charge carriers and demonstrates preferential orientation of(002)crystal plane,which is favorable for corrosion resistance and dendrite-free zinc deposition.Consequently,Zn|UiO-66-GF-2.2|Zn cells exhibit highly reversible plating/stripping behavior with long cycle life over 1650 h at 2.0 mA cm^(−2),and Zn|UiO-66-GF-2.2|MnO_(2) cells show excellent long-term stability with capacity retention of 85%after 1000 cycles.The reasonable design and application of multifunctional metal organic frameworks modified separators provide useful guidance for constructing durable AZIBs.展开更多
Separators are indispensable components of modern electrochemical energy storage devices such as lithium-ion batteries(LIBs).They perform the critical function of physically separating the electrodes to prevent short-...Separators are indispensable components of modern electrochemical energy storage devices such as lithium-ion batteries(LIBs).They perform the critical function of physically separating the electrodes to prevent short-circuits while permitting the ions to pass through.While conventional separators using polypropylene(PP) and polyethylene(PE) are prone to shrinkage and melting at relatively high temperatures(150℃ or above) causing short circuits and thermal runaway,separators made of thermally stable polyimides(PIs) are electrochemically stable and resistant to high temperatures,and possess good mechanical strength-making them a promising solution to the safety concerns of LIBs.In this review,the research progress on PI separators for use in LIBs is summarized with a special focus on molecular design and microstructural control.In view of the significant progress in advanced chemistries beyond LIBs,recent advances in PI-based membranes for applications in lithium-sulfur,lithium-metal,and solid-state batteries are also reviewed.Finally,practical issues are also discussed along with their prospects.展开更多
Membranes of polypropylene （PP）, PP coated with nano-A1203, PP electrospun with polyvinylidene fluoride- hexafluoropropylene （PVdF-HFP）, and trilayer laminates of polypropylene-polyethylene-polypropylene （PP/PE/P...Membranes of polypropylene （PP）, PP coated with nano-A1203, PP electrospun with polyvinylidene fluoride- hexafluoropropylene （PVdF-HFP）, and trilayer laminates of polypropylene-polyethylene-polypropylene （PP/PE/PP） were comparatively studied. Their physical properties were characterized by means of thermal shrinkage test, liquid electrolyte uptake, and field emission scanning electron microscopy （FESEM）. Results show that, for the different membranes as PP, PP coated with nanowA1203, PP electrospun with PVdF-HFP, and PP/PE/PP, the thermal shrinkages are 14%, 6%, 12.6%, and 13.3%, while the liquid electrolyte uptakes are 110%, 150%, 217%, and 129%, respectively. In addition, the effects on the performance of lithium-ion batteries （LiFePO4 and LiNil/3Col/3Mn1/302 as the cathode material） were investigated by AC impedance and galvanostatic charge/discharge test. It is found that PP coated with A1203 and PP electrospun with PVdF-HFP can effectively increase the wettability between the cathode material and liquid electrolyte, and therefore reduce the charge transfer resistance, which improves the capacity retention and battery performance.展开更多
The basic flow model of laminar flow field and the trajectory model of dispersed phase drops are derived. Based on the comparable volumetric flow rate, the dispersed flow rate can be linearly discretized. Consequently...The basic flow model of laminar flow field and the trajectory model of dispersed phase drops are derived. Based on the comparable volumetric flow rate, the dispersed flow rate can be linearly discretized. Consequently, the trajectory of a droplet in the channel can be tracked, and the trajectories of all drops are observed in order to statistically analyse the drops for capture or entrainment. Therefore, in terms of theoretical model of motion, the stratified two phase flow systems are studied in the mixture of nitrobenzene and concentrated sulfuric acid. The analytical results indicate that the trajectories of droplets of different diameters are different at the same location. The larger droplets can help to promote the efficiency of plate separators. The thickness of trickling film has a significant influence on the efficiency of numerical simulation when the concentration of the dispersed phase is greater than 10%. So the modification of thickness of trickling film can help to get the real flow field efficiency. The low flow rate lowers the average Renolds number so that the lighter phase droplets have sufficient time to interact with the trickling film. It is an indispensable factor for predicting efficiency that coalesced drops flow off inclined plates together with trickling films. A comparison confirms that the simulation results are in good agreement with the experiment results.展开更多
One of the major problems limiting the applications of electric double-layer(EDLC)supercapacitor devices is their inability to maintain their cell voltage over a significant period.Self-discharge is a spontaneous deca...One of the major problems limiting the applications of electric double-layer(EDLC)supercapacitor devices is their inability to maintain their cell voltage over a significant period.Self-discharge is a spontaneous decay in charged energy,often resulting in fully depleted devices in a matter of hours.Here,a new method for suppressing this self-discharge phenomenon is proposed by using directionally polarized piezoelectric electrospun nanofiber films as separator materials.Tailored engineering of polyvinylidene fluoride(PVDF)nanofiber films containing a small concentration of sodium dodecyl sulfate(SDS)results in a high proportion of polarβphases,reaching 380.5%of the total material.Inducing polarity into the separator material provides a reverse-diode mechanism in the device,such that it drops from an initial voltage of 1.6 down to 1 V after 10 h,as opposed to 0.3 V with a nonpolarized,commercial separator material.Thus,the energy retained for the polarized separator is 37%and 4%for the nonpolarized separator,making supercapacitors a more attractive solution for long-term energy storage.展开更多
To make magnetic separator more excellent in beneficiation, an advanced automatic control system for magnetic separator was designed. This paper designs automatic control system for magnetic separators, combination wi...To make magnetic separator more excellent in beneficiation, an advanced automatic control system for magnetic separator was designed. This paper designs automatic control system for magnetic separators, combination with PLC and technology of vary frequency. This system can wholly supervise and control the parameters of work course of magnetic separators.展开更多
As the energy density of lithium-ion batteries (LIBs) continues to increase,their safety has become a great concern for further practical large-scale applications.One of the ultimate solution of the safety issue is to...As the energy density of lithium-ion batteries (LIBs) continues to increase,their safety has become a great concern for further practical large-scale applications.One of the ultimate solution of the safety issue is to develop intrinsically safe battery components,where the battery separators and liquid electrolytes are critical for the battery thermal runaway process.In this review,we summarize recent progress in the rational materials design on battery separators and liquid electrolyte towards the goal of improving the safety of LIBs.Also,some strategies for further improving safety of LIBs are also briefly outlooked.展开更多
PM2.5 separator directly affects the accuracy of PM2.5 sampling.The specification testing and evaluation for PM2.5 separator is particularly important,especially under China’s wide variation of terrain and climate.In...PM2.5 separator directly affects the accuracy of PM2.5 sampling.The specification testing and evaluation for PM2.5 separator is particularly important,especially under China’s wide variation of terrain and climate.In this study,first a static test apparatus based on polydisperse aerosol was established and calibrated to evaluate the performance of the PM2.5 separators.A uniform mixing chamber was developed to make particles mix completely.The aerosol concentration relative standard deviations of three test points at the same horizontal chamber position were less than 0.57%,and the particle size distribution obeyed logarithmic normal distribution with an R2 of 0.996.The flow rate deviation between the measurement and the set point flow rate agreed to within±1.0%in the range of-40 to 50℃.Secondly,the separation,flow and loading characteristics of three cyclone separators(VSCC-A,SCC-A and SCC112)were evaluated using this system.The results showed that the 50%cutoff sizes(D50)of the three cyclones were 2.48,2.47 and 2.44μm when worked at the manufacturer’s recommended flow rates,respectively.The geometric standard deviation(GSD)of the capture efficiency of VSCCA was 1.23,showed a slightly sharper than SCC-A(GSD=1.27),while the SCC112 did not meet the relevant indicator(GSD=1.2±0.1)with a GSD=1.44.The flow rate and loading test had a great effect on D50,while the GSD remained almost the same as before.In addition,the maintenance frequency under different air pollution conditions of the cyclones was summarized according to the loading test.展开更多
Droplet behavior in the wave-type flow channel is discussed, especially with the secondary .droplet generation due to impingement of droplets on the wall considered. A numerical method is suggested to simulate tile dr...Droplet behavior in the wave-type flow channel is discussed, especially with the secondary .droplet generation due to impingement of droplets on the wall considered. A numerical method is suggested to simulate tile droplet behavior in the flow field. Calculations are compared With experimental data on the ; pressure drop and separating efficiency. Good agreement exists between the calculations and air-water experiments. The numerical method developed gives a reasonable description of the droplet deposition and secondary droplet generation, and it can be applied to predict the performance of wave-type vane separators.展开更多
The performances of lithium-ion batteries(LIBs)are dependent on the wettability and stability of porous separators.Musselinspired coatings seem to be useful to improve the surface wettability of commercialized polyole...The performances of lithium-ion batteries(LIBs)are dependent on the wettability and stability of porous separators.Musselinspired coatings seem to be useful to improve the surface wettability of commercialized polyolefin separators.However,it is still a challenge to guarantee their stability under polar electrolytes.Herein,we report a facile and versatile way to enhance the wettability and stability of polypropylene separators by constructing robust polydopamine(PDA)coatings triggered with CuSO4/H2O2.These coatings were conveniently deposited on the polypropylene separator surfaces and the PDA-coated separators exhibited the improved surface wettability and thermal stability.The electrolyte uptake increased nearly two folds from the pristine separator to the modified ones.Correspondingly,the ionic conductivity also rose from 0.82 mS·cm^-1 to 1.30 mS·cm^-1.Most importantly,the CuSO4/H2O2-triggered PDA coatings were very stable under strong polar electrolytes,endowing the cells with excellent cycle performance and enhanced C-rate capacity.Overall,the results unequivocally demonstrate that application of PDA coatings on polyolefin separator triggered by CuSO4/H2O2 is a facile and efficient method for improving the wettability and stability of separators for high LIBs performance.展开更多
Surface chemical modification of polyolefin separators for lithium ion batteries is attempted to reduce the thermal shrinkage, which is im- portant for the battery energy density. In this study, we grafted organic/ino...Surface chemical modification of polyolefin separators for lithium ion batteries is attempted to reduce the thermal shrinkage, which is im- portant for the battery energy density. In this study, we grafted organic/inorganic hybrid crosslinked networks on the separators, simply by grafting polymerization and condensation reaction. The considerable silicon-oxygen crosslinked heat-resistance networks are responsible for the reduced thermal shrinkage. The strong chemical bonds between networks and separators promise enough mechanical support even at high temperature. The shrinkage at 150 ℃ for 30 min in the mechanical direction was 38.6% and 4.6% for the pristine and present graft-modified separators, respectively. Meanwhile, the grafting organic-inorganic hybrid crosslink networks mainly occupied part of void in the internal pores of the separators, so the thicknesses of the graft-modified separators were similar with the pristine one. The half cells prepared with the modified separators exhibited almost identical electrochemical properties to those with the commercial separators, thus proving that, in order to enhance the thermal stability of lithium ion battery, this kind of grafting-modified separators may be a better alternative to conventional silica nanoparticle layers-coated polyolefin separators.展开更多
基金the Center of Lithium Battery Membrane Materials jointly established by School of Chemistry and Chemical Engineering of Huazhong University of Science and Technology and Shenzhen Senior Technology Material Co.Ltd.,the National Natural Science Foundation of China(52020105012,52303084)the Young Scientists Fund of Natural Science Foundation of Hubei Province(2023AFB220)for the support of this work.
文摘The growing demands for energy storage systems,electric vehicles,and portable electronics have significantly pushed forward the need for safe and reliable lithium batteries.It is essential to design functional separators with improved mechanical and electrochemical characteristics.This review covers the improved mechanical and electrochemical performances as well as the advancements made in the design of separators utilizing a variety of techniques.In terms of electrolyte wettability and adhesion of the coating materials,we provide an overview of the current status of research on coated separators,in situ modified separators,and grafting modified separators,and elaborate additional performance parameters of interest.The characteristics of inorganics coated separators,organic framework coated separators and inorganic-organic coated separators from different fabrication methods are compared.Future directions regarding new modified materials,manufacturing process,quantitative analysis of adhesion and so on are proposed toward next-generation advanced lithium batteries.
基金financially supported by National Natural Science Foundation of China(No.22304055)Central Guiding Local Science and Technology Development Fund Project(No.236Z4409G)+3 种基金Natural Science Foundation of Hebei Province(No.D2023209012,B2022209026)Youth Talent Program of Hebei Province Education Department(No.BJ2025032)Science and Technology Planning Project of Tangshan City(No.22130227H)Youth Scholars Promotion Plan of North China University of Science and Technology(No.QNTJ202306).
文摘Zinc-based batteries have attracted widespread attention due to their inherent safety,notable cost-effectiveness and consistent performance,etc.However,the advancement of zinc-based battery technology encounters significant challenges,including the formation of zinc dendrites and irreversible side reactions.Separators are vital in batteries due to their role in preventing electrode contact and facilitating rapid movement of ions within the electrolyte.The incorporation of cellulose in batteries enables uniform ion transport and a stable electricfield,attributed to its excellent hydrophilicity,strong mechanical strength,and abundant active sites.Herein,the latest research progress of cellulose-based separators on various zinc-based batteries is systematically summarized.To begin with,the accomplishments and inherent limitations of traditional sep-arators are clarified.Next,it underscores the advantages of cellulose-based materials in battery technology,thoroughly examining their utilization and merits as separators in zinc-based batteries.Lastly,the review offers prospective insights into the future trajectory of cellulose-based separators in zinc-based batteries.Through a comprehensive analysis of the present landscape,the review establishes a framework for the future design and enhancement of cellulose-based separators,thereby fostering the progression of associated industries.
基金supported by the National Natural Science Foundation of China(No.U22A20422,22178028)the Program of Introducing Talents of Discipline to Universities(Project 111,B21022)the 5·5 Engineering Research&Innovation Team Project of Beijing Forestry University(No.BLRC2023B01)。
文摘Separators in supercapacitors(SCs)frequently suffer from high resistance and the risk of short circuits due to inadequate electrolyte wettability,depressed mechanical properties,and insufficient thermal stability.Here,we develop a high-performance regenerated cellulose separator with nano-cracked structures for SCs via a binary solvent of superbase-derived ionic liquid and dimethylsulfoxide(DMSO).The unique nano-cracks with an average width of 7.45 nm arise from the acceleration of cellulose molecular reassembly by DMSO-regulated hydrogen bonding,which endows the separator with high porosity(70.2%)and excellent electrolyte retention(329%).The outstanding thermal stability(273℃)and mechanical strength(70 MPa)enable the separator to maintain its structural integrity under high temperatures and external forces.With these benefits,the SC utilizing the cellulose separator enables a high specific capacitance of 93.6 F g^(−1) at 1.0 A g^(−1) and a remarkable capacitance retention of 99.5%after 10,000 cycles compared with the commercial NKK-MPF30AC and NKK-TF4030.The robust and high-wettability cellulose separator holds promise as a superior alternative to commercial separators for advanced SCs with enhanced performance and improved safety.
基金supported by the National Natural Science Foundation of China(No.51972066)the Natural Science Foundation of Guangdong Province of China(No.2024A1515012499)。
文摘The uneven deposition and high reactivity of lithium-metal anode(LMA)lead to uncontrollable dendrite growth,low Coulombic efficiency,and safety concerns,hindering their commercialization.Here,a representative polar-rich-group triazine-based covalent organic framework(COF-TzDha)with a desolvation effect is designed as an interlayer for stable,dendrite-free LMA.The abundant triazine rings in COFTzDha as a donor effectively attract lithium ions,while the one-dimensional nanopore structure facilitates lithium-ion migration.The periodic arrangement of polar groups(-OH)in the backbone interacts with electrolyte components(DOL,DME,TFSI-)to form a hydrogen bonding network that slows solvent molecules transport.Therefore,COF-TzDha effectively desolvates lithium ions from the solvent sheath,promoting uniform lithium ion flux and Li plating/stripping.Theoretical calculations verify that COFTzDha with abundant adsorption sites and strong adsorption energy facilitates lithium ion desolvation.Consequently,the introduction of COF-TzDha obtains a high ion mobility(0.75).The Li|COF@PP|Li symmetric cell cycles stably for over 1200 h at 4 mA cm^(-2)/4.0 mA h cm^(-2).The Li|COF@PP|LiFePO_(4)full cell also displays highly stable cycling performance with 600 cycles(75.5%capacity retention,~100% Coulombic efficiency)at 1 C.This work verifies an effective strategy for inducing uniform Li deposition and achieving dendrite-free,stable LMA using a polar-rich-group COF interlayer with a desolvation effect.
基金supported by Beijing Institute of Technology Student Innovation Training Program(BIT2024LH013).
文摘The thermal stability of lithium-ion battery separators is a critical determinant of battery safety and performance,especially in the context of rapidly expanding applications in electric vehicles and energy storage systems.While traditional polyolefin separators(PP/PE)dominate the market due to their cost-effectiveness and mechanical robustness,their inherent poor thermal stability poses significant safety risks under high-temperature conditions.This review provides a comprehensive analysis of recent advancements in enhancing separator thermal stability through coating materials(metal,ceramic,inorganic)and novel high-temperature-resistant polymers(e.g.,PVDF copolymers,PI,PAN).Notably,we critically evaluate the trade-offs between thermal resilience and electrochemical performance,such as the unintended increase in electronic conductivity from metal coatings(e.g.,Cu,MOFs)and reduced electrolyte wettability in ceramic coatings(e.g.,Al_(2)O_(3)).Innovations in hybrid coatings(e.g.,BN/PAN composites,gradient-structured MOFs)and scalable manufacturing techniques(e.g.,roll-to-roll electrospinning)are highlighted as promising strategies to balance these competing demands.Furthermore,a comparative analysis of next-generation high-temperature-resistant separators underscores their ionic conductivity,mechanical strength,and scalability,offering actionable insights for material selection.The review concludes with forward-looking perspectives on integrating machine learning for material discovery,optimizing interfacial adhesion in ceramic coatings,and advancing semi-/all-solid-state batteries to address both thermal and electrochemical challenges.This work aims to bridge the gap between laboratory innovations and industrial applications,fostering safer and more efficient lithium battery technologies.
基金supported by Beijing Natural Science Foundation(Nos.2232037 and 2242035)the National Natural Science Foundation of China(Nos.22005012,22105012 and 51803183)+1 种基金Chunhui Plan Cooperative Project of Ministry of Education(No.202201298)the China Postdoctoral Science Foundation Funded Project(No.2023M733520).
文摘Lithium-sulfur(Li-S)batteries with high energy density and capacity have garnered significant research attention among various energy storage devices.However,the shuttle effect of polysulfides(LiPSs)remains a major challenge for their practical application.The design of battery separators has become a key aspect in addressing the challenge.MXenes,a promising two-dimensional(2D)material,offer exceptional conductivity,large surface area,high mechanical strength,and active sites for surface reactions.When assembled into layered films,MXenes form highly tunable two-dimensional channels ranging from a few angstroms to over 1 nm.These nanoconfined channels are instrumental in facilitating lithium-ion transport while effectively impeding the shuttle effect of LiPSs,which are essential for improving the specific capacity and cyclic stability of Li-S batteries.Substantial progress has been made in developing MXenes-based separators for Li-S batteries,yet there remains a research gap in summarizing advancements from the perspective of interlayer engineering.This entails maintaining the 2D nanochannels of layered MXenes-based separators while modulating the physicochemical environment within the MXenes interlayers through targeted modifications.This review highlights advancements in in situ modification of MXenes and their integration with 0D,1D,and 2D materials to construct laminated nanocomposite separators for Li-S batteries.The future development directions of MXenes-based materials in Li-S energy storage devices are also outlined,to drive further advancements in MXenes for Li-S battery separators.
基金2023 undergraduate Innovation and Entrepreneurship Project of Yichun University(S202310417015)。
文摘There are some inherent defects for the polyolefin based lithium battery separator,such as,poor thermal stability,poor electrolyte wettability and low porosity,which limit the development of lithium battery.An important way to improve the performance of lithium battery is to improve the separator.Here,three novel separators combined with metal-organic framework materials(MOFs)and carbon materials were prepared by using the in situ growth method and the adsorption combination method simultaneously.The result showed that compared with the polypropylene separator,the porosity and electrolyte wettability were significantly improved in view of these novel polypropylene separators combined with MOFs and carbon materials.Meanwhile,the electrochemical performance of lithium battery equipped with the polypropylene separator combined with MOFs materials and carbon materials was also improved.The result showed that lithium batteries equipped with polypropylene separator combined with MOFs and carbon materials had higher capacity in the first charge and discharge cycle and better electrochemical kinetic reaction processes.
基金The authors gratefully acknowledge financial support from Dagong Equipment Manufacturing(Tianjin)Co.,Ltd.(53H23019)the Tianjin Research Innovation Project for Postgraduate Students(2022BKYZ037)the National Natural Science Foundation of China(22179093).
文摘Due to the limitations of the raw materials and processes involved,polyolefin separators used in commercial lithium-ion batteries(LIBs)have gradually failed to meet the increasing requirements of high-end batteries in terms of energy density,power density,and safety.Hence,it is very important to develop next-generation separators for advanced lithium(Li)-based recharge-able batteries including LIBs and Li-S batteries.Nonwoven nanofiber membranes fabricated via electrospinning technology are highly attractive candidates for high-end separators due to their simple processes,low-cost equipment,controllable microporous structure,wide material applicability,and availability of multiple functions.In this review,the electrospinning technologies for separators are reviewed in terms of devices,process and environment,and polymer solution systems.Furthermore,strategies toward the improvement of electrospun separators in advanced LIBs and Li-S batteries are presented in terms of the compositions and the structure of nanofibers and separators.Finally,the challenges and prospects of electrospun separators in both academia and industry are proposed.We anticipate that these systematic discussions can provide information in terms of commercial applications of electrospun separators and offer new perspectives for the design of functional electrospun separators for advanced Li-based batteries.
基金Project supported by Guangzhou Science and Technology Project,China (201803020038)Guangdong Science and Technology Commissioner Project (GDKTP2020046700)Innovation and Entrepreneurship Training Program for University Students (202324040)。
文摘Lithium-sulfur(Li-S) batteries have generated significant attention due to their high theoretical specific capacity and energy density among a host of energy storage power devices.Nevertheless,the lithium polysulfide dissolution shuttle that occurs within Li-S batteries will lead to capacity deterioration and inadequate cycling stability.In the paper,we proposed a measure to deal with the above problems by modifying the separator with Nd_(2)O_(3)/graphene composite in Li-S batteries.Graphene's special chemical properties and structural qualities make it an excellent choice for Li-S batteries.Meanwhile,Nd_(2)O_(3) has a strong binding affinity with lithium polysulfide due to its low electronegativity,which exhibits Lewis' s acidity and forms strong interactions with lithium polysulfide,which is strongly Lewis basic.By utilizing these advantageous properties,Li-S batteries assembling Nd_(2)O_(3)-decorated reduced graphite oxide modified polypropylene separators(Nd_(2)O_(3)/RGO/PP) demonstrate outstanding electrochemical performance,including a mere 0.0525% capacity attenuation rate under 2C during 1000 cycles and with exceptional rate performance of 614 mAh/g even at 3C.This study presents valuable knowledge for effectively modifying separators using rare earth oxides to incorporate graphene,ultimately promoting the practical application of Li-S batteries.
基金This work was supported by the National Natural Science Foundation of China(Nos.51872090,51972346)the Hebei Natural Science Fund for Distinguished Young Scholar(No.E2019209433)+2 种基金the Natural Science Foundation of Hebei Province(No.E2020209151)the Hunan Natural Science Fund for Distinguished Young Scholar(2021JJ10064)the Program of Youth Talent Support for Hunan Province(2020RC3011).
文摘Aqueous zinc-ion batteries(AZIBs)are one of the promising energy storage systems,which consist of electrode materials,electrolyte,and separator.The first two have been significantly received ample development,while the prominent role of the separators in manipulating the stability of the electrode has not attracted sufficient attention.In this work,a separator(UiO-66-GF)modified by Zr-based metal organic framework for robust AZIBs is proposed.UiO-66-GF effectively enhances the transport ability of charge carriers and demonstrates preferential orientation of(002)crystal plane,which is favorable for corrosion resistance and dendrite-free zinc deposition.Consequently,Zn|UiO-66-GF-2.2|Zn cells exhibit highly reversible plating/stripping behavior with long cycle life over 1650 h at 2.0 mA cm^(−2),and Zn|UiO-66-GF-2.2|MnO_(2) cells show excellent long-term stability with capacity retention of 85%after 1000 cycles.The reasonable design and application of multifunctional metal organic frameworks modified separators provide useful guidance for constructing durable AZIBs.
基金supported by the Basic Research Program of Shenzhen(No.JCYJ20190812161409163)the Basic and Applied Basic Research Program of Guangdong Province(No.2019A1515110531)the SIAT Innovation Program for Excellent Young Researchers。
文摘Separators are indispensable components of modern electrochemical energy storage devices such as lithium-ion batteries(LIBs).They perform the critical function of physically separating the electrodes to prevent short-circuits while permitting the ions to pass through.While conventional separators using polypropylene(PP) and polyethylene(PE) are prone to shrinkage and melting at relatively high temperatures(150℃ or above) causing short circuits and thermal runaway,separators made of thermally stable polyimides(PIs) are electrochemically stable and resistant to high temperatures,and possess good mechanical strength-making them a promising solution to the safety concerns of LIBs.In this review,the research progress on PI separators for use in LIBs is summarized with a special focus on molecular design and microstructural control.In view of the significant progress in advanced chemistries beyond LIBs,recent advances in PI-based membranes for applications in lithium-sulfur,lithium-metal,and solid-state batteries are also reviewed.Finally,practical issues are also discussed along with their prospects.
基金supported by the Fundamental Research Funds for the Central Universities of China(No.FRF-MP-12-005B)the Project on International Cooperation Research with Johnson Controls Battery Group,Inc.
文摘Membranes of polypropylene （PP）, PP coated with nano-A1203, PP electrospun with polyvinylidene fluoride- hexafluoropropylene （PVdF-HFP）, and trilayer laminates of polypropylene-polyethylene-polypropylene （PP/PE/PP） were comparatively studied. Their physical properties were characterized by means of thermal shrinkage test, liquid electrolyte uptake, and field emission scanning electron microscopy （FESEM）. Results show that, for the different membranes as PP, PP coated with nanowA1203, PP electrospun with PVdF-HFP, and PP/PE/PP, the thermal shrinkages are 14%, 6%, 12.6%, and 13.3%, while the liquid electrolyte uptakes are 110%, 150%, 217%, and 129%, respectively. In addition, the effects on the performance of lithium-ion batteries （LiFePO4 and LiNil/3Col/3Mn1/302 as the cathode material） were investigated by AC impedance and galvanostatic charge/discharge test. It is found that PP coated with A1203 and PP electrospun with PVdF-HFP can effectively increase the wettability between the cathode material and liquid electrolyte, and therefore reduce the charge transfer resistance, which improves the capacity retention and battery performance.
文摘The basic flow model of laminar flow field and the trajectory model of dispersed phase drops are derived. Based on the comparable volumetric flow rate, the dispersed flow rate can be linearly discretized. Consequently, the trajectory of a droplet in the channel can be tracked, and the trajectories of all drops are observed in order to statistically analyse the drops for capture or entrainment. Therefore, in terms of theoretical model of motion, the stratified two phase flow systems are studied in the mixture of nitrobenzene and concentrated sulfuric acid. The analytical results indicate that the trajectories of droplets of different diameters are different at the same location. The larger droplets can help to promote the efficiency of plate separators. The thickness of trickling film has a significant influence on the efficiency of numerical simulation when the concentration of the dispersed phase is greater than 10%. So the modification of thickness of trickling film can help to get the real flow field efficiency. The low flow rate lowers the average Renolds number so that the lighter phase droplets have sufficient time to interact with the trickling film. It is an indispensable factor for predicting efficiency that coalesced drops flow off inclined plates together with trickling films. A comparison confirms that the simulation results are in good agreement with the experiment results.
基金the UK Engineering and Physical Sciences Research Council(EPSRC)for funding this work under the Doctoral Training Partnership(DTP)award(EP/N509772/1).
文摘One of the major problems limiting the applications of electric double-layer(EDLC)supercapacitor devices is their inability to maintain their cell voltage over a significant period.Self-discharge is a spontaneous decay in charged energy,often resulting in fully depleted devices in a matter of hours.Here,a new method for suppressing this self-discharge phenomenon is proposed by using directionally polarized piezoelectric electrospun nanofiber films as separator materials.Tailored engineering of polyvinylidene fluoride(PVDF)nanofiber films containing a small concentration of sodium dodecyl sulfate(SDS)results in a high proportion of polarβphases,reaching 380.5%of the total material.Inducing polarity into the separator material provides a reverse-diode mechanism in the device,such that it drops from an initial voltage of 1.6 down to 1 V after 10 h,as opposed to 0.3 V with a nonpolarized,commercial separator material.Thus,the energy retained for the polarized separator is 37%and 4%for the nonpolarized separator,making supercapacitors a more attractive solution for long-term energy storage.
文摘To make magnetic separator more excellent in beneficiation, an advanced automatic control system for magnetic separator was designed. This paper designs automatic control system for magnetic separators, combination with PLC and technology of vary frequency. This system can wholly supervise and control the parameters of work course of magnetic separators.
基金the support from the National Natural Science Foundation of China(General Program no.51874041)。
文摘As the energy density of lithium-ion batteries (LIBs) continues to increase,their safety has become a great concern for further practical large-scale applications.One of the ultimate solution of the safety issue is to develop intrinsically safe battery components,where the battery separators and liquid electrolytes are critical for the battery thermal runaway process.In this review,we summarize recent progress in the rational materials design on battery separators and liquid electrolyte towards the goal of improving the safety of LIBs.Also,some strategies for further improving safety of LIBs are also briefly outlooked.
基金supported by the National Key Research and Development Program of China(Nos.2016YFF0103004 and 2017YFC0209504)the National Natural Science Foundation of China(No.91544218)+1 种基金the Science and Technological Fund of Anhui Province for Outstanding Youth(No.1808085J19)the Special Research of Public Welfare Industry of Environmental Protection(201409011)
文摘PM2.5 separator directly affects the accuracy of PM2.5 sampling.The specification testing and evaluation for PM2.5 separator is particularly important,especially under China’s wide variation of terrain and climate.In this study,first a static test apparatus based on polydisperse aerosol was established and calibrated to evaluate the performance of the PM2.5 separators.A uniform mixing chamber was developed to make particles mix completely.The aerosol concentration relative standard deviations of three test points at the same horizontal chamber position were less than 0.57%,and the particle size distribution obeyed logarithmic normal distribution with an R2 of 0.996.The flow rate deviation between the measurement and the set point flow rate agreed to within±1.0%in the range of-40 to 50℃.Secondly,the separation,flow and loading characteristics of three cyclone separators(VSCC-A,SCC-A and SCC112)were evaluated using this system.The results showed that the 50%cutoff sizes(D50)of the three cyclones were 2.48,2.47 and 2.44μm when worked at the manufacturer’s recommended flow rates,respectively.The geometric standard deviation(GSD)of the capture efficiency of VSCCA was 1.23,showed a slightly sharper than SCC-A(GSD=1.27),while the SCC112 did not meet the relevant indicator(GSD=1.2±0.1)with a GSD=1.44.The flow rate and loading test had a great effect on D50,while the GSD remained almost the same as before.In addition,the maintenance frequency under different air pollution conditions of the cyclones was summarized according to the loading test.
基金Supported by the National Key Laboratory of Bubble Physics&Natural Circulation(No.51482150104JW0502).
文摘Droplet behavior in the wave-type flow channel is discussed, especially with the secondary .droplet generation due to impingement of droplets on the wall considered. A numerical method is suggested to simulate tile droplet behavior in the flow field. Calculations are compared With experimental data on the ; pressure drop and separating efficiency. Good agreement exists between the calculations and air-water experiments. The numerical method developed gives a reasonable description of the droplet deposition and secondary droplet generation, and it can be applied to predict the performance of wave-type vane separators.
基金financially supported by the Zhejiang Provincial Natural Science Foundation of China (No. LZ15E030001)the National Natural Science Foundation of China (No. 21534009)
文摘The performances of lithium-ion batteries(LIBs)are dependent on the wettability and stability of porous separators.Musselinspired coatings seem to be useful to improve the surface wettability of commercialized polyolefin separators.However,it is still a challenge to guarantee their stability under polar electrolytes.Herein,we report a facile and versatile way to enhance the wettability and stability of polypropylene separators by constructing robust polydopamine(PDA)coatings triggered with CuSO4/H2O2.These coatings were conveniently deposited on the polypropylene separator surfaces and the PDA-coated separators exhibited the improved surface wettability and thermal stability.The electrolyte uptake increased nearly two folds from the pristine separator to the modified ones.Correspondingly,the ionic conductivity also rose from 0.82 mS·cm^-1 to 1.30 mS·cm^-1.Most importantly,the CuSO4/H2O2-triggered PDA coatings were very stable under strong polar electrolytes,endowing the cells with excellent cycle performance and enhanced C-rate capacity.Overall,the results unequivocally demonstrate that application of PDA coatings on polyolefin separator triggered by CuSO4/H2O2 is a facile and efficient method for improving the wettability and stability of separators for high LIBs performance.
基金supported by the MOST(Grant No.2013CB934000,2014DFG71590,2011CB935902,2010DFA72760,2011CB711202,2013AA050903,2011AA11A257 and 2011AA11A254)China Postdoctoral Science Foundation(Grant No.2013M530599 and 2013M540929)+2 种基金Tsinghua University Initiative Scientific Research Program(Grant No.2010THZ08116,2011THZ08139,2011THZ01004 and 2012THZ08129)the State Key Laboratory of Automotive Safety and Energy(No.ZZ2012-011)Suzhou(Wujiang)Automotive Research Institute,Tsinghua University,Project No.2012WJ-A-01
文摘Surface chemical modification of polyolefin separators for lithium ion batteries is attempted to reduce the thermal shrinkage, which is im- portant for the battery energy density. In this study, we grafted organic/inorganic hybrid crosslinked networks on the separators, simply by grafting polymerization and condensation reaction. The considerable silicon-oxygen crosslinked heat-resistance networks are responsible for the reduced thermal shrinkage. The strong chemical bonds between networks and separators promise enough mechanical support even at high temperature. The shrinkage at 150 ℃ for 30 min in the mechanical direction was 38.6% and 4.6% for the pristine and present graft-modified separators, respectively. Meanwhile, the grafting organic-inorganic hybrid crosslink networks mainly occupied part of void in the internal pores of the separators, so the thicknesses of the graft-modified separators were similar with the pristine one. The half cells prepared with the modified separators exhibited almost identical electrochemical properties to those with the commercial separators, thus proving that, in order to enhance the thermal stability of lithium ion battery, this kind of grafting-modified separators may be a better alternative to conventional silica nanoparticle layers-coated polyolefin separators.
