Lithium metal batteries(LMBs)are emerging as a promising energy storage solution owing to their high energy density and specific capacity.However,the non-uniform plating of lithium and the potential rupture of the sol...Lithium metal batteries(LMBs)are emerging as a promising energy storage solution owing to their high energy density and specific capacity.However,the non-uniform plating of lithium and the potential rupture of the solid-electrolyte interphase(SEI)during extended cycling use may result in dendrite growth,which can penetrate the separator and pose significant short-circuit risks.Forming a stable SEI is essential for the long-term operation of the batteries.Fluorine-rich SEI has garnered significant attention for its ability to effectively passivate electrodes,regulate lithium deposition,and inhibit electrolyte corrosion.Understanding the structural components and preparation methods of existing fluorinated SEI is crucial for optimizing lithium metal anode performance.This paper reviews the research on optimizing LiF passivation interfaces to protect lithium metal anodes.It focuses on four types of compositions in fluorinated SEI that work synergistically to enhance SEI performance.For instance,combining compounds with LiF can further enhance the mechanical strength and ionic conductivity of the SEI.Integrating metals with LiF significantly improves electrochemical performance at the SEI/anode interface,with a necessary focus on reducing electron tunneling risks.Additionally,incorporating polymers with LiF offers balanced improvements in interfacial toughness and ionic conductivity,though maintaining structural stability over long cycles remains a critical area for future research.Although alloys combined with LiF increase surface energy and lithium affinity,challenges such as dendrite growth and volume expansion persist.In summary,this paper emphasizes the crucial role of interfacial structures in LMBs and offers comprehensive guidance for future design and development efforts in battery technology.展开更多
The battery energy density can be improved by raising the operating voltage,however,which may lead to rapid capacity decay due to the continuous electrolyte decomposition and the thickening of electrode electrolyte in...The battery energy density can be improved by raising the operating voltage,however,which may lead to rapid capacity decay due to the continuous electrolyte decomposition and the thickening of electrode electrolyte interphases.To address these challenges,we proposed tripropyl phosphate(TPP)as an additive-regulating Li~+solvation structure to construct a stable Li F–rich electrode carbonate-based electrolyte interphases for sustaining 4.6 V Li||LiCoO_(2)batteries.This optimized interphases could help reduce the resistance and achieve better rate performance and cycling stability.As expected,the Li||LiCoO_(2)battery retained 79.4%capacity after 100 cycles at 0.5 C,while the Li||Li symmetric cell also kept a stable plating/stripping process over 450 h at the current density of 1.0 mA/cm^(2)with a deposited amount of0.5 mAh/cm^(2).展开更多
The electrochemical performance of Li metal anode is closely bound up with the interphase between Li and lithium-loaded skeleton as well as solid electrolyte interphase(SEI)on Li surface.Herein,for the first time,we p...The electrochemical performance of Li metal anode is closely bound up with the interphase between Li and lithium-loaded skeleton as well as solid electrolyte interphase(SEI)on Li surface.Herein,for the first time,we propose a novel liquid-source CHBr_(2)F plasma technology to simultaneously construct dual bromine-fluorine-enriched interphases:NiBr_(2)-NiF_(2) interphase on sponge Ni(SN)skeleton and LiBr-LiF-enriched SEI on Li anode,respectively.Based on density functional theory(DFT)calculations and COMSOL multiphysics simulation results,SN skeleton with NiBr_(2)-NiF_(2)interphase can effectively decrease the local current density with good lithiophilicity.And the LiBr-LiF-enriched SEI on Li surface can function to block electron tunneling and hinder side electrochemical reduction of electrolyte components,thus suppressing the growth of dendrite and facilitating the homogeneous transportation of lithium ions.Consequently,the Li/SN electrodes with modified interphases show remarkable stability with a low overpotential of 22.6 mV over 1800 h at 1 mA cm^(-2)/1 mAh cm^(-2)and an exceptional average Coulombic efficiency of 99.6%.When coupled with LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)cathode,the full cells deliver improved cycling stability with a capacity retention of 79.5%even after 350 cycles at 0.5 C.This study provides a facile and new plasma method for the construction of advanced Li anodes for energy storage.展开更多
Lithium metal shows a great advantage as the most promising anode for its unparalleled theoretical specific capacity and extremely low electrochemical potential.However,uncontrolled lithium dendrite growth and severe ...Lithium metal shows a great advantage as the most promising anode for its unparalleled theoretical specific capacity and extremely low electrochemical potential.However,uncontrolled lithium dendrite growth and severe side reactions of the reactive intermediates and organic electrolytes still limit the broad application of lithium metal batteries.Herein,we propose 4-nitrobenzenesulfonyl fluoride(NBSF)as an electrolyte additive for forming a stable organic-inorganic hybrid solid electrolyte interphase(SEI)layer on the lithium surface.The abundance of lithium fluoride and lithium nitride can guarantee the SEI layer's toughness and high ionic conductivity,achieving dendrite-free lithium deposition.Meanwhile,the phenyl group of NBSF significantly contributes to both the chemical stability of the SEI layer and the good adaptation to volume changes of the lithium anode.The lithium-oxygen batteries with NBSF exhibit prolonged cycle lives and excellent cycling stability.This simple approach is hoped to improve the development of the organic-inorganic SEI layer to stabilize the lithium anodes for lithium-oxygen batteries.展开更多
Li metal has been regarded as one of the most promising anodes for high-energy-density storage systems due to its high theoretical capacity and lowest electrochemical potential.Unfortunately,an unstable and non-unifor...Li metal has been regarded as one of the most promising anodes for high-energy-density storage systems due to its high theoretical capacity and lowest electrochemical potential.Unfortunately,an unstable and non-uniform solid electrolyte interphase(SEI)deriving from the spontaneous reaction between Li metal anode and electrolyte causes uneven Li deposition,resulting in the growth of Li dendrites and low Coulombic efficiency,which have greatly hindered the practical application of Li metal batteries.Thus,the construction of a stable SEI is an effective approach to suppress the growth of Li dendrites and enhance the electrochemical performances of Li metal anode.In this review,we firstly introduce the formation process of inferior SEI of Li metal anode and the corresponding challenges caused by the unstable SEI.Next,recent progresses to modify SEI layer through the regulation of electrolyte compositions and exsitu protective coating are summarized.Finally,the remained issues,challenges,and perspectives are also proposed on the basis of current research status and progress.展开更多
Aiming to obtain microwave absorbing materials with excellent mechanical and microwave absorption properties, carbon fiber reinforced Si3N4 ceramics(Cf-Si3N4) with pyrolytic carbon(PyC)/SiC interphases were fabricated...Aiming to obtain microwave absorbing materials with excellent mechanical and microwave absorption properties, carbon fiber reinforced Si3N4 ceramics(Cf-Si3N4) with pyrolytic carbon(PyC)/SiC interphases were fabricated by gel casting. The influences of carbon fibers content on mechanical and microwave absorption properties of as-prepared Si3N4 based ceramics were investigated. Results show that chemical compatibility between carbon fibers and Si3N4 matrix in high temperature environment can be significantly improved after introduction of Py C/SiC interphases. As carbon fibers content increases from 0 to 4 wt%, flexural strength of Si3N4 based ceramics decreases slightly while fracture toughness obviously increases. Moreover, both the real and imaginary parts of complex permittivity increase with the rising of carbon fibers content within the frequency range of 8.2–12.4 GHz. Investigation of microwave absorption shows that the microwave attenuation ability of Cf-Si3N4 ceramics with Py C/SiC interphases is remarkably enhanced compared with pure Si3N4 ceramics. Effective absorption bandwidth(<-10 d B) of10.17–12.4 GHz and the minimum reflection less of-19.6 d B are obtained for Si3N4 ceramics with 4 wt%carbon fibers in 2.0 mm thickness. Cf-Si3N4 ceramics with Py C/SiC interphases are promising candidates for microwave absorbing materials with favorable mechanical property.展开更多
The resourceful and inexpensive red phosphorus has emerged as a promising anode material of potassium-ion batteries(PIBs) for its large theoretical capacities and low redox potentials in the multielectron alloying/dea...The resourceful and inexpensive red phosphorus has emerged as a promising anode material of potassium-ion batteries(PIBs) for its large theoretical capacities and low redox potentials in the multielectron alloying/dealloying reactions,yet chronically suffering from the huge volume expansion/shrinkage with a sluggish reaction kinetics and an unsatisfactory interfacial stability against volatile electrolytes.Herein,we systematically developed a series of localized high-concentration electrolytes(LHCE) through diluting high-concentration ether electrolytes with a non-solvating fluorinated ether to regulate the formation/evolution of solid electrolyte interphases(SEI) on phosphorus/carbon(P/C) anodes for PIBs.Benefitting from the improved mechanical strength and structural stability of a robust/uniform SEI thin layer derived from a composition-optimized LHCE featured with a unique solvation structure and a superior K+migration capability,the P/C anode with noticeable pseudocapacitive behaviors could achieve a large reversible capacity of 760 mA h g^(-1)at 100 mA g^(-1),a remarkable capacity retention rate of 92.6% over 200 cycles at 800 mA g^(-1),and an exceptional rate capability of 334 mA h g^(-1)at8000 mA g^(-1).Critically,a suppressed reduction of ether solvents with a preferential decomposition of potassium salts in anion-derived interfacial reactions on P/C anode for LHCE could enable a rational construction of an outer organic-rich and inner inorganic-dominant SEI thin film with remarkable mechanical strength/flexibility to buffer huge volume variations and abundant K+diffusion channels to accelerate reaction kinetics.Additionally,the highly reversible/durable full PIBs coupling P/C anodes with annealed organic cathodes further verified an excellent practical applicability of LHCE.This encouraging work on electrolytes regulating SEI formation/evolution would advance the development of P/C anodes for high-performance PIBs.展开更多
Anti-plane deformation of square lattices containing interphases is analyzed. It is assumed that lattices are linear elastic but not necessarily isotropic, whereas interphases exhibit non-linear elastic behavior. It i...Anti-plane deformation of square lattices containing interphases is analyzed. It is assumed that lattices are linear elastic but not necessarily isotropic, whereas interphases exhibit non-linear elastic behavior. It is demonstrated that such problems can be treated effectively using Green＇s functions, which allow to eliminate the degrees of freedom outside of the interphase. Illustrative numerical examples focus on the determination of applied stresses leading to lattice instability.展开更多
Li-metal is an ideal anode that can provide rechargeable batteries with high energy density,but its application in large scale is restricted by its high activity that leads to the severe decomposition of electrolyte c...Li-metal is an ideal anode that can provide rechargeable batteries with high energy density,but its application in large scale is restricted by its high activity that leads to the severe decomposition of electrolyte components(solvents and salts) and the growth of Li dendrites.These parasitic reactions are responsible for the cycle life deterioration and the safety accidents of rechargeable Li-metal batteries.Correspondingly,much effort has been made to regulate Li/electrolyte interface chemistry.In this review,we summarize some strategies that have been developed recently to stabilize Li/electrolyte interface by constructing protective interphases on Li-metal anodes.Firstly,the currently available understandings on the instability of Li/electrolyte interface are outlined.Then,artificial interphases recently constructed exsitu and in-situ are illustrated in detail.Finally,possible approaches to acquire more efficiently protective interphases are prospected.展开更多
In this paper,a Voronoi cell finite element model is developed to study the microscopic and macroscopic mechanical behaviors of heterogenous materials,including arbitrary distributed heterogeneity(inclusions or fibers...In this paper,a Voronoi cell finite element model is developed to study the microscopic and macroscopic mechanical behaviors of heterogenous materials,including arbitrary distributed heterogeneity(inclusions or fibers)coated with interphase layers,based on linear elasticity theory.The interphase between heterogeneity and a matrix are regarded as in the third phase(elastic layers),in contrast to the perfect interface of the spring-like Voronoi cell finite element model(VCFEM)in the literature.In this model,both stress and the displacement field are assumed to be independent in an element.Formulations of stress are derived for each of the three phases in an element,as is the type of functional.Numerical examples were used to study the microscopic and macroscopic properties,such as the effective modulus,of the composites.The results of the proposed VCFEM were compared with analytical solution and numerical results obtained from a standard finite element analysis to confirm its effectiveness.展开更多
High energy density lithium-ion batteries using Ni-rich cathode(such as LiNi0.6Co0.2Mn0.2O2) suffer from severe capacity decay.P-toluenesulfonyl fluoride(pTSF) has been investigated as a novel film-forming electrolyte...High energy density lithium-ion batteries using Ni-rich cathode(such as LiNi0.6Co0.2Mn0.2O2) suffer from severe capacity decay.P-toluenesulfonyl fluoride(pTSF) has been investigated as a novel film-forming electrolyte additive to enhance the cycling performances of graphite/LiNi0.6Co0.2Mn0.2O2 pouch cell.In comparison with the baseline electrolyte,a small dose of pTSF can significantly improve the cyclic stability of the cell.Theoretical calculations together with experimental results indicate that pTSF would be oxidized and reduced to construct protective interphase film on the surfaces of LiNi0.6Co0.2Mn0.2O2 cathode and graphite anode,respectively.These S-containing surface films derived from pTSF effectively mitigate the decomposition of electrolyte,reduce the interphasial impedance,as well as prevent the dissolution of transition metal ions from Ni-rich cathode upon cycling at high voltage.This finding is beneficial for the practical application of high energy density graphite/LiNi0.6Co0.2Mn0.2O2 cells.展开更多
Ni-rich lithium nickel–cobalt-manganese oxides(NCM) are considered the most promising cathode materials for lithium-ion batteries(LIBs);however, relatively poor cycling performance is a bottleneck preventing their wi...Ni-rich lithium nickel–cobalt-manganese oxides(NCM) are considered the most promising cathode materials for lithium-ion batteries(LIBs);however, relatively poor cycling performance is a bottleneck preventing their widespread use in energy systems. In this work, we propose the use of a dually functionalized surface modifier, calcium sulfate(CaSO_(4), CSO), in an efficient one step method to increase the cycling performance of Ni-rich NCM cathode materials. Thermal treatment of LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811) cathode materials with a CSO precursor allows the formation of an artificial Ca-and SO_(x)-functionalized cathode–electrolyte interphase(CEI) layer on the surface of Ni-rich NCM cathode materials. The CEI layer then inhibits electrolyte decomposition at the interface between the Ni-rich NCM cathode and the electrolyte. Successful formation of the CSO-modified CEI layer is confirmed by scanning electron microscopy(SEM) and Fourier transform infrared(FTIR) spectroscopy analyses, and the process does not affect the bulk structure of the Ni-rich NCM cathode material. During cycling, the CSO-modified CEI layer remarkably decreases electrolyte decomposition upon cycling at both room temperature and 45 ℃, leading to a substantial increase in cycling retention of the cells. A cell cycled with a 0.1 CSO-modified(modified with 0.1% CSO)NCM811 cathode exhibits a specific capacity retention of90.0%, while the cell cycled with non-modified NCM811 cathode suffers from continuous fading of cycling retention(74.0%) after 100 cycles. SEM, electrochemical impedance spectroscopy(EIS), X-ray photoelectron spectroscopy(XPS), and inductively coupled plasma mass spectrometry(ICP-MS) results of the recovered electrodes demonstrate that undesired surface reactions such as electrolyte decomposition and metal dissolution are well controlled in the cell because of the artificial CSO-modified CEI layer present on the surface of Ni-rich NCM811 cathodes.展开更多
This paper derives the complementary energy functional based on the Voronoi element of particle-reinforced composites containing interphases to compute the interfacial debonding and thermal stress.When calculating int...This paper derives the complementary energy functional based on the Voronoi element of particle-reinforced composites containing interphases to compute the interfacial debonding and thermal stress.When calculating interfacial debonding stress,it is assumed that the surface force is zero at the interface where debonding occurs,and a new modified complementary energy functional is derived with this boundary condition.When considering the thermal stress due to temperature change,the thermal strain is introduced into the complementary energy functional,and the thermal stress is then calculated.According to the derived formula,a Fortran program named Voronoi cell finite element model(VCFEM)is written.The interfacial debonding and thermal stress is calculated using both VCFEM and the finite element software MARC,and the calculation results are compared.It shows that the calculation results of the VCFEM are roughly comparable to those of the MARC,verifying the effectiveness of the VCFEM.展开更多
By transforming the governing equations for displacement components into Riccati equations, analytical solutions for displacements, strains and stresses for Representive Volume Elements (RVEs) of particle_ and fiber_r...By transforming the governing equations for displacement components into Riccati equations, analytical solutions for displacements, strains and stresses for Representive Volume Elements (RVEs) of particle_ and fiber_reinforced composites containing inhomo geneous interphases were obtained. The analytical solutions derived here are new and general for power_law variations of the elastic moduli of the inhomogeneous interphases. Given a power exponent, analytical expressions for the bulk moduli of the composites with inho mogeneous interphases can be obtained. By changing the power exponent and the coefficients of the power terms, the solutions derived here can be applied to inhomogeneous interphases with many different property profiles. The results show that the modulus variation and the thickness of the inhomogeneous interphase have great effect on the bulk moduli of the composites. The particle will exhibit a sort of “size effect”, if there is an interphase.展开更多
As promising candidates for high-energy-density lithium-ion batteries,both silicon(Si)anodes and nickel-rich cathodes face significant challenges due to structural instability arising from interphases.In this study,we...As promising candidates for high-energy-density lithium-ion batteries,both silicon(Si)anodes and nickel-rich cathodes face significant challenges due to structural instability arising from interphases.In this study,we introduced tetravinylsilane(TVSi)as a multifunctional electrolyte additive to engineer tai-lored interphases simultaneously on Si anode and LiNi_(0.92)Mn_(0.05)Co_(0.03)O_(2)cathode,thereby enhancing their electrochemical performance.On one front,TVSi underwent polymerization,leading to the for-mation of a composite solid electrolyte interphase(SEI)with an interpenetrating network structure on the Si surface.This SEI effectively accommodated volume changes during cycling,which inhibited SEI growth,hence,preserving the battery capacity.On the other hand,the TVSi-induced cathode electrolyte interphase(CEI)exhibited a dense structure com-prising a chemically bonded silicate-silane polymer.This CEI effectively mitigated transition metal disso-lution by scavenging hydrofluoric acid(HF)and re-duced irreversible phase transitions by minimizing side reactions.As a result of the enhanced interfacial stability achieved on both electrodes,TVSi enabled improved performance in full cells fabricated with a LiNi_(0.92)Mn_(0.05)Co_(0.03)O_(2)cathode paired with a Si anode.This multifunctional additive strategy offers a novel perspective on additive design for high-energy-density lithium-ion batteries,showcasing its potential for advancing battery technology.展开更多
Interfacial engineering,particularly the design of artificial solid-electrolyte interphases(SEIs),has been successfully applied in all-solid-state batteries(ASSLBs)for industrial applications.However,a fundamental und...Interfacial engineering,particularly the design of artificial solid-electrolyte interphases(SEIs),has been successfully applied in all-solid-state batteries(ASSLBs)for industrial applications.However,a fundamental understanding of the synthesis and mechanism models of artificial SEIs in all-solid-state Li-ion batteries remains limited.In this review,recent advances in designing and synthesizing artificial SEIs for ASSLBs to solve interfacial issues are thoroughly discussed,covering three main preparation methods and their technical routes:1)atomic layer deposition,2)sol-gel methods,and 3)mechanical ball-milling methods.Moreover,advanced ex-situ characterization techniques for artificial SEIs are comprehensively summarized.Finally,this review provides perspectives on techniques for the interface engineering of artificial SEIs for ASSLBs,with focus on promising methods for industrial applications.展开更多
Hard carbon (HC) has been considered as promising anode material for sodium-ion batteries (SIBs).The optimization of hard carbon’s microstructure and solid electrolyte interface (SEI) property are demonstrated effect...Hard carbon (HC) has been considered as promising anode material for sodium-ion batteries (SIBs).The optimization of hard carbon’s microstructure and solid electrolyte interface (SEI) property are demonstrated effective in enhancing the Na+storage capability,however,a one-step regulation strategy to achieve simultaneous multi-scale structures optimization is highly desirable.Herein,we have systematically investigated the effects of boron doping on hard carbon’s microstructure and interface chemistry.A variety of structure characterizations show that appropriate amount of boron doping can increase the size of closed pores via rearrangement of carbon layers with improved graphitization degree,which provides more Na+storage sites.In-situ Fourier transform infrared spectroscopy/electrochemical impedance spectroscopy (FTIR/EIS) and X-ray photoelectron spectroscopy (XPS) analysis demonstrate the presence of more BC3and less B–C–O structures that result in enhanced ion diffusion kinetics and the formation of inorganic rich and robust SEI,which leads to facilitated charge transfer and excellent rate performance.As a result,the hard carbon anode with optimized boron doping content exhibits enhanced rate and cycling performance.In general,this work unravels the critical role of boron doping in optimizing the pore structure,interface chemistry and diffusion kinetics of hard carbon,which enables rational design of sodium-ion battery anode with enhanced Na+storage performance.展开更多
Quasi-solid-state lithium-metal batteries(QSLMBs)are promising candidates for next-generation battery systems due to their high energy density and enhanced safety.However,their practical application has been hindered ...Quasi-solid-state lithium-metal batteries(QSLMBs)are promising candidates for next-generation battery systems due to their high energy density and enhanced safety.However,their practical application has been hindered by low ionic conductivity and the growth of lithium dendrites.To achieve ordered transport of Li^(+)ions in quasi-solid electrolytes(QSEs),improve ionic conductivity,and homogenize Li^(+)fluxes on the surface of the lithium metal anode(LMA),we propose a novel method.This method involves constructing"ion relay stations"in QSEs by introducing cyano-functionalized boron nitride nanosheets into pentaerythritol tetraacrylate(PETEA)-based polymer electrolytes.The functionalized boron nitride nanosheets promote the dissociation of lithium salts through ion-dipole interactions,optimizing the solvated structure to facilitate the orderly transport of Li+ions,resulting in an ionic conductivity of2.5×10^(-3)S cm^(-1)at 30℃.Notably,this strategy regulates the Li^(+)distribution on the surface of the LMA,effectively inhibiting the growth of lithium dendrites,Li‖Li symmetrical cells using this type of electrolyte maintain stability for over 2000 h at 2 mA cm^(-2)and 2 mAh cm^(-2).Additionally,with a high LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)loading of 8.5 mg cm^(-2),the cells exhibit excellent cycling performance,retaining a high capacity after 400 cycles.This innovative QSE design strategy represents a significant advancement towards the development of high-performance QSLMBs.展开更多
Solid-state batteries(SSBs)will potentially offer increased energy density and,more importantly,improved safety for next generation lithium-ion(Li-ion)batteries.One enabling technology is solid-state composite cathode...Solid-state batteries(SSBs)will potentially offer increased energy density and,more importantly,improved safety for next generation lithium-ion(Li-ion)batteries.One enabling technology is solid-state composite cathodes with high operating voltage and area capacity.Current composite cathode manufacturing technologies,however,suffer from large interfacial resistance and low active mass loading that with excessive amounts of polymer electrolytes and conductive additives.Here,we report a liquidphase sintering technology that offers mixed ionic-electronic interphases and free-standing electrode architecture design,which eventually contribute to high area capacity.A small amount(~4 wt.%)of lithium hydroxide(LiOH)and boric acid(H_(3)BO_(3))with low melting point are utilized as sintering additives that infiltrate into single-crystal Ni-rich LiNi_(0.8)Mn_(0.1)Co_(0.1)(NMC811)particles at a moderately elevated temperature(~350℃)in a liquid state,which not only enable intimate physical contact but also promote the densification process.In addition,the liquid-phase additives react and transform to ionic-conductive lithium boron oxide,together with the indium tin oxide(ITO)nanoparticle coating,mixed ionic-electronic interphases of composite cathode are successfully fabricated.Furthermore,the liquid-phase sintering performed at high-temperature(~800℃)also enables the fabrication of highly dense and thick composite cathodes with a novel free-standing architecture.The promising performance characteristics of such composite cathodes,for example,delivering an area capacity above 8 mAh·cm^(−2) within a wide voltage window up to 4.4 V,open new opportunities for SSBs with a high energy density of 500 Wh·kg^(−1) for safer portable electronic and electrical transport.展开更多
Fluoride-based electrolyte exhibits extraordinarily high oxidative stability in high-voltage lithium metal batteries(h-LMBs) due to the inherent low highest occupied molecular orbital(HOMO) of fiuorinated solvents. Ho...Fluoride-based electrolyte exhibits extraordinarily high oxidative stability in high-voltage lithium metal batteries(h-LMBs) due to the inherent low highest occupied molecular orbital(HOMO) of fiuorinated solvents. However, such fascinating properties do not bring long-term cyclability of h-LMBs. One of critical challenges is the interface instability in contacting with the Li metal anode, as fiuorinated solvents are highly susceptible to exceptionally reductive metallic Li attributed to its low lowest unoccupied molecular orbital(LUMO), which leads to significant consumption of the fiuorinated components upon cycling.Herein, attenuating reductive decomposition of fiuorinated electrolytes is proposed to circumvent rapid electrolyte consumption. Specifically, the vinylene carbonate(VC) is selected to tame the reduction decomposition by preferentially forming protective layer on the Li anode. This work, experimentally and computationally, demonstrates the importance of pre-passivation of Li metal anodes at high voltage to attenuate the decomposition of fiuoroethylene carbonate(FEC). It is expected to enrich the understanding of how VC attenuate the reactivity of FEC, thereby extending the cycle life of fiuorinated electrolytes in high-voltage Li-metal batteries.展开更多
基金support from the National Natural Science Foundation of China(No.U2333210)the Sichuan Science and Technology Program,China(No.21SYSX0011)。
文摘Lithium metal batteries(LMBs)are emerging as a promising energy storage solution owing to their high energy density and specific capacity.However,the non-uniform plating of lithium and the potential rupture of the solid-electrolyte interphase(SEI)during extended cycling use may result in dendrite growth,which can penetrate the separator and pose significant short-circuit risks.Forming a stable SEI is essential for the long-term operation of the batteries.Fluorine-rich SEI has garnered significant attention for its ability to effectively passivate electrodes,regulate lithium deposition,and inhibit electrolyte corrosion.Understanding the structural components and preparation methods of existing fluorinated SEI is crucial for optimizing lithium metal anode performance.This paper reviews the research on optimizing LiF passivation interfaces to protect lithium metal anodes.It focuses on four types of compositions in fluorinated SEI that work synergistically to enhance SEI performance.For instance,combining compounds with LiF can further enhance the mechanical strength and ionic conductivity of the SEI.Integrating metals with LiF significantly improves electrochemical performance at the SEI/anode interface,with a necessary focus on reducing electron tunneling risks.Additionally,incorporating polymers with LiF offers balanced improvements in interfacial toughness and ionic conductivity,though maintaining structural stability over long cycles remains a critical area for future research.Although alloys combined with LiF increase surface energy and lithium affinity,challenges such as dendrite growth and volume expansion persist.In summary,this paper emphasizes the crucial role of interfacial structures in LMBs and offers comprehensive guidance for future design and development efforts in battery technology.
基金supported by the National Natural Science Foundation of China(No.U21A20311)the Distinguished Scientist Fellowship Program(DSFP)at King Saud University,Riyadh,Saudi Arabia。
文摘The battery energy density can be improved by raising the operating voltage,however,which may lead to rapid capacity decay due to the continuous electrolyte decomposition and the thickening of electrode electrolyte interphases.To address these challenges,we proposed tripropyl phosphate(TPP)as an additive-regulating Li~+solvation structure to construct a stable Li F–rich electrode carbonate-based electrolyte interphases for sustaining 4.6 V Li||LiCoO_(2)batteries.This optimized interphases could help reduce the resistance and achieve better rate performance and cycling stability.As expected,the Li||LiCoO_(2)battery retained 79.4%capacity after 100 cycles at 0.5 C,while the Li||Li symmetric cell also kept a stable plating/stripping process over 450 h at the current density of 1.0 mA/cm^(2)with a deposited amount of0.5 mAh/cm^(2).
基金National Natural Science Foun-dation of China(Grant Nos.52372235,52073252,52002052 and 22379020)Natural Science Foundation for Distinguished Young Scholars of Zhejiang Province(Grant No.LR20E020001)+5 种基金Zhejiang Provincial Natural Science Foundation of China(No.LQ23E020009)Science and Technology Department of Zhejiang Province(Grant No.2023C01231)Key Research and Development Project of Science and Technology Department of Sichuan Province(No.2022YFSY0004)Key Laboratory of Engineering Dielectrics and Its Application(Harbin University of Science and Technology)Min-istry of Education(Grant No.KFM 202202)Open Project Program of the State Key Laboratory of Photocatalysis on Energy and Environment(Grant No.SKLPEE-KF202206),Fuzhou University.
文摘The electrochemical performance of Li metal anode is closely bound up with the interphase between Li and lithium-loaded skeleton as well as solid electrolyte interphase(SEI)on Li surface.Herein,for the first time,we propose a novel liquid-source CHBr_(2)F plasma technology to simultaneously construct dual bromine-fluorine-enriched interphases:NiBr_(2)-NiF_(2) interphase on sponge Ni(SN)skeleton and LiBr-LiF-enriched SEI on Li anode,respectively.Based on density functional theory(DFT)calculations and COMSOL multiphysics simulation results,SN skeleton with NiBr_(2)-NiF_(2)interphase can effectively decrease the local current density with good lithiophilicity.And the LiBr-LiF-enriched SEI on Li surface can function to block electron tunneling and hinder side electrochemical reduction of electrolyte components,thus suppressing the growth of dendrite and facilitating the homogeneous transportation of lithium ions.Consequently,the Li/SN electrodes with modified interphases show remarkable stability with a low overpotential of 22.6 mV over 1800 h at 1 mA cm^(-2)/1 mAh cm^(-2)and an exceptional average Coulombic efficiency of 99.6%.When coupled with LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)cathode,the full cells deliver improved cycling stability with a capacity retention of 79.5%even after 350 cycles at 0.5 C.This study provides a facile and new plasma method for the construction of advanced Li anodes for energy storage.
基金The authors gratefully acknowledge the support of the National Natural Science Foundation(Grant No.22109131,52077180)Sichuan Province Innovative Talent Funding Project for Postdoctoral Fellows,Young Elite Scientists Sponsorship Program(CAST,2022QNRC001)+1 种基金the Natural Science Foundation of Sichuan Province(No.2022NSFSC0247)Southwest Jiaotong University's New Interdisciplinary Cultivation Fund(No.2682022KJ028).
文摘Lithium metal shows a great advantage as the most promising anode for its unparalleled theoretical specific capacity and extremely low electrochemical potential.However,uncontrolled lithium dendrite growth and severe side reactions of the reactive intermediates and organic electrolytes still limit the broad application of lithium metal batteries.Herein,we propose 4-nitrobenzenesulfonyl fluoride(NBSF)as an electrolyte additive for forming a stable organic-inorganic hybrid solid electrolyte interphase(SEI)layer on the lithium surface.The abundance of lithium fluoride and lithium nitride can guarantee the SEI layer's toughness and high ionic conductivity,achieving dendrite-free lithium deposition.Meanwhile,the phenyl group of NBSF significantly contributes to both the chemical stability of the SEI layer and the good adaptation to volume changes of the lithium anode.The lithium-oxygen batteries with NBSF exhibit prolonged cycle lives and excellent cycling stability.This simple approach is hoped to improve the development of the organic-inorganic SEI layer to stabilize the lithium anodes for lithium-oxygen batteries.
基金financially supported by the National Natural Science Foundation of China(Grant no.51678182)China Postdoctoral Science Foundation(Grant no.2019M650663)Start-up Grant of Harbin Institute of Technology,Shenzhen。
文摘Li metal has been regarded as one of the most promising anodes for high-energy-density storage systems due to its high theoretical capacity and lowest electrochemical potential.Unfortunately,an unstable and non-uniform solid electrolyte interphase(SEI)deriving from the spontaneous reaction between Li metal anode and electrolyte causes uneven Li deposition,resulting in the growth of Li dendrites and low Coulombic efficiency,which have greatly hindered the practical application of Li metal batteries.Thus,the construction of a stable SEI is an effective approach to suppress the growth of Li dendrites and enhance the electrochemical performances of Li metal anode.In this review,we firstly introduce the formation process of inferior SEI of Li metal anode and the corresponding challenges caused by the unstable SEI.Next,recent progresses to modify SEI layer through the regulation of electrolyte compositions and exsitu protective coating are summarized.Finally,the remained issues,challenges,and perspectives are also proposed on the basis of current research status and progress.
基金supported by the National Natural Science Foundation of China (Grant No. 51604107)the Natural Science Foundation of Hunan Province (Grant No. 2019JJ50115 and 2019JJ50768)
文摘Aiming to obtain microwave absorbing materials with excellent mechanical and microwave absorption properties, carbon fiber reinforced Si3N4 ceramics(Cf-Si3N4) with pyrolytic carbon(PyC)/SiC interphases were fabricated by gel casting. The influences of carbon fibers content on mechanical and microwave absorption properties of as-prepared Si3N4 based ceramics were investigated. Results show that chemical compatibility between carbon fibers and Si3N4 matrix in high temperature environment can be significantly improved after introduction of Py C/SiC interphases. As carbon fibers content increases from 0 to 4 wt%, flexural strength of Si3N4 based ceramics decreases slightly while fracture toughness obviously increases. Moreover, both the real and imaginary parts of complex permittivity increase with the rising of carbon fibers content within the frequency range of 8.2–12.4 GHz. Investigation of microwave absorption shows that the microwave attenuation ability of Cf-Si3N4 ceramics with Py C/SiC interphases is remarkably enhanced compared with pure Si3N4 ceramics. Effective absorption bandwidth(<-10 d B) of10.17–12.4 GHz and the minimum reflection less of-19.6 d B are obtained for Si3N4 ceramics with 4 wt%carbon fibers in 2.0 mm thickness. Cf-Si3N4 ceramics with Py C/SiC interphases are promising candidates for microwave absorbing materials with favorable mechanical property.
基金supported by the National Key Research and Development Program of China(2021YFB2400200)the National Natural Science Foundation of China(52104313,22172117,52072298)the Scientific Research Program of Shaanxi Provincial Education Department(21JK0808)。
文摘The resourceful and inexpensive red phosphorus has emerged as a promising anode material of potassium-ion batteries(PIBs) for its large theoretical capacities and low redox potentials in the multielectron alloying/dealloying reactions,yet chronically suffering from the huge volume expansion/shrinkage with a sluggish reaction kinetics and an unsatisfactory interfacial stability against volatile electrolytes.Herein,we systematically developed a series of localized high-concentration electrolytes(LHCE) through diluting high-concentration ether electrolytes with a non-solvating fluorinated ether to regulate the formation/evolution of solid electrolyte interphases(SEI) on phosphorus/carbon(P/C) anodes for PIBs.Benefitting from the improved mechanical strength and structural stability of a robust/uniform SEI thin layer derived from a composition-optimized LHCE featured with a unique solvation structure and a superior K+migration capability,the P/C anode with noticeable pseudocapacitive behaviors could achieve a large reversible capacity of 760 mA h g^(-1)at 100 mA g^(-1),a remarkable capacity retention rate of 92.6% over 200 cycles at 800 mA g^(-1),and an exceptional rate capability of 334 mA h g^(-1)at8000 mA g^(-1).Critically,a suppressed reduction of ether solvents with a preferential decomposition of potassium salts in anion-derived interfacial reactions on P/C anode for LHCE could enable a rational construction of an outer organic-rich and inner inorganic-dominant SEI thin film with remarkable mechanical strength/flexibility to buffer huge volume variations and abundant K+diffusion channels to accelerate reaction kinetics.Additionally,the highly reversible/durable full PIBs coupling P/C anodes with annealed organic cathodes further verified an excellent practical applicability of LHCE.This encouraging work on electrolytes regulating SEI formation/evolution would advance the development of P/C anodes for high-performance PIBs.
文摘Anti-plane deformation of square lattices containing interphases is analyzed. It is assumed that lattices are linear elastic but not necessarily isotropic, whereas interphases exhibit non-linear elastic behavior. It is demonstrated that such problems can be treated effectively using Green＇s functions, which allow to eliminate the degrees of freedom outside of the interphase. Illustrative numerical examples focus on the determination of applied stresses leading to lattice instability.
基金supported by the National Natural Science Foundation of China(Grant No.21872058)。
文摘Li-metal is an ideal anode that can provide rechargeable batteries with high energy density,but its application in large scale is restricted by its high activity that leads to the severe decomposition of electrolyte components(solvents and salts) and the growth of Li dendrites.These parasitic reactions are responsible for the cycle life deterioration and the safety accidents of rechargeable Li-metal batteries.Correspondingly,much effort has been made to regulate Li/electrolyte interface chemistry.In this review,we summarize some strategies that have been developed recently to stabilize Li/electrolyte interface by constructing protective interphases on Li-metal anodes.Firstly,the currently available understandings on the instability of Li/electrolyte interface are outlined.Then,artificial interphases recently constructed exsitu and in-situ are illustrated in detail.Finally,possible approaches to acquire more efficiently protective interphases are prospected.
基金supported by the National Natural Science Foundation of China(Grants 11402103 and 11572142).
文摘In this paper,a Voronoi cell finite element model is developed to study the microscopic and macroscopic mechanical behaviors of heterogenous materials,including arbitrary distributed heterogeneity(inclusions or fibers)coated with interphase layers,based on linear elasticity theory.The interphase between heterogeneity and a matrix are regarded as in the third phase(elastic layers),in contrast to the perfect interface of the spring-like Voronoi cell finite element model(VCFEM)in the literature.In this model,both stress and the displacement field are assumed to be independent in an element.Formulations of stress are derived for each of the three phases in an element,as is the type of functional.Numerical examples were used to study the microscopic and macroscopic properties,such as the effective modulus,of the composites.The results of the proposed VCFEM were compared with analytical solution and numerical results obtained from a standard finite element analysis to confirm its effectiveness.
基金supported by the National Natural Science Foundation of China (21573080)the Guangdong Program for Support of Distinguished Young Scholar (2017B030306013)the Science and Technology Planning Project of Guangdong Province (2017B090901020)。
文摘High energy density lithium-ion batteries using Ni-rich cathode(such as LiNi0.6Co0.2Mn0.2O2) suffer from severe capacity decay.P-toluenesulfonyl fluoride(pTSF) has been investigated as a novel film-forming electrolyte additive to enhance the cycling performances of graphite/LiNi0.6Co0.2Mn0.2O2 pouch cell.In comparison with the baseline electrolyte,a small dose of pTSF can significantly improve the cyclic stability of the cell.Theoretical calculations together with experimental results indicate that pTSF would be oxidized and reduced to construct protective interphase film on the surfaces of LiNi0.6Co0.2Mn0.2O2 cathode and graphite anode,respectively.These S-containing surface films derived from pTSF effectively mitigate the decomposition of electrolyte,reduce the interphasial impedance,as well as prevent the dissolution of transition metal ions from Ni-rich cathode upon cycling at high voltage.This finding is beneficial for the practical application of high energy density graphite/LiNi0.6Co0.2Mn0.2O2 cells.
基金financially supported by the National Research Foundation of Korea(NRF)(Nos.NRF2019R1C1C1002249 and NRF-2017R1A6A1A06015181)the Technology Innovation Program(Nos.20010095 and 20011905)funded by the Ministry of Trade,Industry&Energy(MOTIE,Korea)。
文摘Ni-rich lithium nickel–cobalt-manganese oxides(NCM) are considered the most promising cathode materials for lithium-ion batteries(LIBs);however, relatively poor cycling performance is a bottleneck preventing their widespread use in energy systems. In this work, we propose the use of a dually functionalized surface modifier, calcium sulfate(CaSO_(4), CSO), in an efficient one step method to increase the cycling performance of Ni-rich NCM cathode materials. Thermal treatment of LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811) cathode materials with a CSO precursor allows the formation of an artificial Ca-and SO_(x)-functionalized cathode–electrolyte interphase(CEI) layer on the surface of Ni-rich NCM cathode materials. The CEI layer then inhibits electrolyte decomposition at the interface between the Ni-rich NCM cathode and the electrolyte. Successful formation of the CSO-modified CEI layer is confirmed by scanning electron microscopy(SEM) and Fourier transform infrared(FTIR) spectroscopy analyses, and the process does not affect the bulk structure of the Ni-rich NCM cathode material. During cycling, the CSO-modified CEI layer remarkably decreases electrolyte decomposition upon cycling at both room temperature and 45 ℃, leading to a substantial increase in cycling retention of the cells. A cell cycled with a 0.1 CSO-modified(modified with 0.1% CSO)NCM811 cathode exhibits a specific capacity retention of90.0%, while the cell cycled with non-modified NCM811 cathode suffers from continuous fading of cycling retention(74.0%) after 100 cycles. SEM, electrochemical impedance spectroscopy(EIS), X-ray photoelectron spectroscopy(XPS), and inductively coupled plasma mass spectrometry(ICP-MS) results of the recovered electrodes demonstrate that undesired surface reactions such as electrolyte decomposition and metal dissolution are well controlled in the cell because of the artificial CSO-modified CEI layer present on the surface of Ni-rich NCM811 cathodes.
基金Funding was provided by The national Natural Science Foundation of China (Grant No.12062007).
文摘This paper derives the complementary energy functional based on the Voronoi element of particle-reinforced composites containing interphases to compute the interfacial debonding and thermal stress.When calculating interfacial debonding stress,it is assumed that the surface force is zero at the interface where debonding occurs,and a new modified complementary energy functional is derived with this boundary condition.When considering the thermal stress due to temperature change,the thermal strain is introduced into the complementary energy functional,and the thermal stress is then calculated.According to the derived formula,a Fortran program named Voronoi cell finite element model(VCFEM)is written.The interfacial debonding and thermal stress is calculated using both VCFEM and the finite element software MARC,and the calculation results are compared.It shows that the calculation results of the VCFEM are roughly comparable to those of the MARC,verifying the effectiveness of the VCFEM.
文摘By transforming the governing equations for displacement components into Riccati equations, analytical solutions for displacements, strains and stresses for Representive Volume Elements (RVEs) of particle_ and fiber_reinforced composites containing inhomo geneous interphases were obtained. The analytical solutions derived here are new and general for power_law variations of the elastic moduli of the inhomogeneous interphases. Given a power exponent, analytical expressions for the bulk moduli of the composites with inho mogeneous interphases can be obtained. By changing the power exponent and the coefficients of the power terms, the solutions derived here can be applied to inhomogeneous interphases with many different property profiles. The results show that the modulus variation and the thickness of the inhomogeneous interphase have great effect on the bulk moduli of the composites. The particle will exhibit a sort of “size effect”, if there is an interphase.
基金supported by the National Natural Science Foundation of China(NSFCgrant no.52303263)+1 种基金the Shenzhen Science and Technology Research Grants,China(grant no.JCYJ20200109140416788)the Soft Science Research Project of Guangdong Province,China(grant no.2017B030301013).
文摘As promising candidates for high-energy-density lithium-ion batteries,both silicon(Si)anodes and nickel-rich cathodes face significant challenges due to structural instability arising from interphases.In this study,we introduced tetravinylsilane(TVSi)as a multifunctional electrolyte additive to engineer tai-lored interphases simultaneously on Si anode and LiNi_(0.92)Mn_(0.05)Co_(0.03)O_(2)cathode,thereby enhancing their electrochemical performance.On one front,TVSi underwent polymerization,leading to the for-mation of a composite solid electrolyte interphase(SEI)with an interpenetrating network structure on the Si surface.This SEI effectively accommodated volume changes during cycling,which inhibited SEI growth,hence,preserving the battery capacity.On the other hand,the TVSi-induced cathode electrolyte interphase(CEI)exhibited a dense structure com-prising a chemically bonded silicate-silane polymer.This CEI effectively mitigated transition metal disso-lution by scavenging hydrofluoric acid(HF)and re-duced irreversible phase transitions by minimizing side reactions.As a result of the enhanced interfacial stability achieved on both electrodes,TVSi enabled improved performance in full cells fabricated with a LiNi_(0.92)Mn_(0.05)Co_(0.03)O_(2)cathode paired with a Si anode.This multifunctional additive strategy offers a novel perspective on additive design for high-energy-density lithium-ion batteries,showcasing its potential for advancing battery technology.
基金This research was supported by the National Key R&D Program of China(2022YFB3506300)National Natural Science Foundation of China(No.52176185)+2 种基金Guangdong-Foshan Joint Fund(2023A1515140091)Guangdong High-level Innovation Institute project(2021B090905000)Ningbo Yongjiang Talent Introduction Program(2023A-184-G)Eastern Institute of Technology,Ningbo.
文摘Interfacial engineering,particularly the design of artificial solid-electrolyte interphases(SEIs),has been successfully applied in all-solid-state batteries(ASSLBs)for industrial applications.However,a fundamental understanding of the synthesis and mechanism models of artificial SEIs in all-solid-state Li-ion batteries remains limited.In this review,recent advances in designing and synthesizing artificial SEIs for ASSLBs to solve interfacial issues are thoroughly discussed,covering three main preparation methods and their technical routes:1)atomic layer deposition,2)sol-gel methods,and 3)mechanical ball-milling methods.Moreover,advanced ex-situ characterization techniques for artificial SEIs are comprehensively summarized.Finally,this review provides perspectives on techniques for the interface engineering of artificial SEIs for ASSLBs,with focus on promising methods for industrial applications.
基金National Key Research and Development Program of China (2022YFE0206300)National Natural Science Foundation of China (U21A2081,22075074, 22209047)+3 种基金Guangdong Basic and Applied Basic Research Foundation (2024A1515011620)Hunan Provincial Natural Science Foundation of China (2024JJ5068)Foundation of Yuelushan Center for Industrial Innovation (2023YCII0119)Student Innovation Training Program (S202410532594,S202410532357)。
文摘Hard carbon (HC) has been considered as promising anode material for sodium-ion batteries (SIBs).The optimization of hard carbon’s microstructure and solid electrolyte interface (SEI) property are demonstrated effective in enhancing the Na+storage capability,however,a one-step regulation strategy to achieve simultaneous multi-scale structures optimization is highly desirable.Herein,we have systematically investigated the effects of boron doping on hard carbon’s microstructure and interface chemistry.A variety of structure characterizations show that appropriate amount of boron doping can increase the size of closed pores via rearrangement of carbon layers with improved graphitization degree,which provides more Na+storage sites.In-situ Fourier transform infrared spectroscopy/electrochemical impedance spectroscopy (FTIR/EIS) and X-ray photoelectron spectroscopy (XPS) analysis demonstrate the presence of more BC3and less B–C–O structures that result in enhanced ion diffusion kinetics and the formation of inorganic rich and robust SEI,which leads to facilitated charge transfer and excellent rate performance.As a result,the hard carbon anode with optimized boron doping content exhibits enhanced rate and cycling performance.In general,this work unravels the critical role of boron doping in optimizing the pore structure,interface chemistry and diffusion kinetics of hard carbon,which enables rational design of sodium-ion battery anode with enhanced Na+storage performance.
基金supported by the Natural Science Foundation of China(52488201)。
文摘Quasi-solid-state lithium-metal batteries(QSLMBs)are promising candidates for next-generation battery systems due to their high energy density and enhanced safety.However,their practical application has been hindered by low ionic conductivity and the growth of lithium dendrites.To achieve ordered transport of Li^(+)ions in quasi-solid electrolytes(QSEs),improve ionic conductivity,and homogenize Li^(+)fluxes on the surface of the lithium metal anode(LMA),we propose a novel method.This method involves constructing"ion relay stations"in QSEs by introducing cyano-functionalized boron nitride nanosheets into pentaerythritol tetraacrylate(PETEA)-based polymer electrolytes.The functionalized boron nitride nanosheets promote the dissociation of lithium salts through ion-dipole interactions,optimizing the solvated structure to facilitate the orderly transport of Li+ions,resulting in an ionic conductivity of2.5×10^(-3)S cm^(-1)at 30℃.Notably,this strategy regulates the Li^(+)distribution on the surface of the LMA,effectively inhibiting the growth of lithium dendrites,Li‖Li symmetrical cells using this type of electrolyte maintain stability for over 2000 h at 2 mA cm^(-2)and 2 mAh cm^(-2).Additionally,with a high LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)loading of 8.5 mg cm^(-2),the cells exhibit excellent cycling performance,retaining a high capacity after 400 cycles.This innovative QSE design strategy represents a significant advancement towards the development of high-performance QSLMBs.
基金supported by Natural Science Foundation of Jiangsu Province(No.BK20200800)the National Natural Science Foundation of China(Nos.51902165,12004145,52072323,and 52122211)+2 种基金Natural Science Foundation of Jiangxi Province(Nos.20192ACBL2004 and 20212BAB214032)Nanjing Science&Technology Innovation Project for Personnel Studying AbroadPart of the calculations were supported by the Center for Computational Science and Engineering at Southern University of Science and Technology,and high-performance computing platform of Jinggangshan University.
文摘Solid-state batteries(SSBs)will potentially offer increased energy density and,more importantly,improved safety for next generation lithium-ion(Li-ion)batteries.One enabling technology is solid-state composite cathodes with high operating voltage and area capacity.Current composite cathode manufacturing technologies,however,suffer from large interfacial resistance and low active mass loading that with excessive amounts of polymer electrolytes and conductive additives.Here,we report a liquidphase sintering technology that offers mixed ionic-electronic interphases and free-standing electrode architecture design,which eventually contribute to high area capacity.A small amount(~4 wt.%)of lithium hydroxide(LiOH)and boric acid(H_(3)BO_(3))with low melting point are utilized as sintering additives that infiltrate into single-crystal Ni-rich LiNi_(0.8)Mn_(0.1)Co_(0.1)(NMC811)particles at a moderately elevated temperature(~350℃)in a liquid state,which not only enable intimate physical contact but also promote the densification process.In addition,the liquid-phase additives react and transform to ionic-conductive lithium boron oxide,together with the indium tin oxide(ITO)nanoparticle coating,mixed ionic-electronic interphases of composite cathode are successfully fabricated.Furthermore,the liquid-phase sintering performed at high-temperature(~800℃)also enables the fabrication of highly dense and thick composite cathodes with a novel free-standing architecture.The promising performance characteristics of such composite cathodes,for example,delivering an area capacity above 8 mAh·cm^(−2) within a wide voltage window up to 4.4 V,open new opportunities for SSBs with a high energy density of 500 Wh·kg^(−1) for safer portable electronic and electrical transport.
基金supported by the National Natural Science Foundation of China (Nos. 22379121, 62005216)Basic Public Welfare Research Program of Zhejiang (No. LQ22F050013)+1 种基金Zhejiang Province Key Laboratory of Flexible Electronics Open Fund (2023FE005)Shenzhen Foundation Research Program (No. JCYJ20220530112812028)。
文摘Fluoride-based electrolyte exhibits extraordinarily high oxidative stability in high-voltage lithium metal batteries(h-LMBs) due to the inherent low highest occupied molecular orbital(HOMO) of fiuorinated solvents. However, such fascinating properties do not bring long-term cyclability of h-LMBs. One of critical challenges is the interface instability in contacting with the Li metal anode, as fiuorinated solvents are highly susceptible to exceptionally reductive metallic Li attributed to its low lowest unoccupied molecular orbital(LUMO), which leads to significant consumption of the fiuorinated components upon cycling.Herein, attenuating reductive decomposition of fiuorinated electrolytes is proposed to circumvent rapid electrolyte consumption. Specifically, the vinylene carbonate(VC) is selected to tame the reduction decomposition by preferentially forming protective layer on the Li anode. This work, experimentally and computationally, demonstrates the importance of pre-passivation of Li metal anodes at high voltage to attenuate the decomposition of fiuoroethylene carbonate(FEC). It is expected to enrich the understanding of how VC attenuate the reactivity of FEC, thereby extending the cycle life of fiuorinated electrolytes in high-voltage Li-metal batteries.
