The solid-state lithium battery is considered as an ideal next-generation energy storage device owing to its high safety,high energy density and low cost.However,the poor ionic conductivity of solid electrolyte and lo...The solid-state lithium battery is considered as an ideal next-generation energy storage device owing to its high safety,high energy density and low cost.However,the poor ionic conductivity of solid electrolyte and low interfacial stability has hindered the application of solid-state lithium battery.Here,a flexible polymer/garnet solid electrolyte is prepared with poly(ethylene oxide),poly(vinylidene fluoride),Li6.75La3 Zr1.75Ta0.25O12,lithium bis(trifluoromethanesulfonyl)imide and oxalate,which exhibits an ionic conductivity of 2.0 ×10^(-4) S cm^(-1) at 55℃,improved mechanical property,wide electrochemical window(4.8 V vs.Li/Li+),enhanced thermal stabilities.Tiny acidic OX was introduced to inhibit the alkalinity reactions between Li6.75La3 Zr1.75Ta0.25O12 and poly(vinylidene fluoride).In order to improve the interfacial stability between cathode and electrolyte,an Al2 O3@LiNi0.5Co0.2Mn0.3O2 based composite cathode framework is also fabricated with poly(ethylene oxide) polymer and lithium salt as additives.The solid-state lithium battery assembled with polymer/garnet solid electrolyte and composite cathode framework demonstrates a high initial discharge capacity of 150.6 mAh g^(-1) and good capacity retention of 86.7% after 80 cycles at 0.2 C and 55℃,which provides a promising choice for achieving the stable electrode/electrolyte interfacial contact in solid-state lithium batteries.展开更多
The stability of Zn anode in various Znbased energy storage devices is the key problem to be solved.Herein,aromatic aldehyde additives are selected to modulate the interface reactions between the Zn anode and electrol...The stability of Zn anode in various Znbased energy storage devices is the key problem to be solved.Herein,aromatic aldehyde additives are selected to modulate the interface reactions between the Zn anode and electrolyte.Through comprehensively considering electrochemical measurements,DFT calculations and FEA simulations,novel mechanisms of one kind of aromatic aldehyde,veratraldehyde in inhibiting Zn dendrite/by-products can be obtained.This additive prefers to absorb on the Zn surface than H_(2)O molecules and Zn^(2+),while competes with hydrogen evolution reaction and Zn plating/stripping proces s via redox reactions,thus preventing the decomposition of active H_(2)O near the interface and uncontrollable Zn dendrite growth via a synactic absorption-competition mechanism.As a result,Zn-Zn symmetric cells with the veratraldehyde additive realize an excellent cycling life of 3200 h under 1 mA cm^(-2)/1 mAh cm^(-2)and over 800 h even under 5 mA cm^(-2)/5 mAh cm^(-2).Moreover,Zn-Ti and Zn-MnO_(2)cells with the veratraldehyde additive both obtain elevated performance than that with pure ZnSO_(4)electrolyte.Finally,two more aromatic aldehyde additives are chosen to prove their universality in stabilizing Zn anodes.展开更多
To effectively alleviate the surface structure degradation caused by electrolyte corrosion and transition metal(TM) dissolution for Ni-rich(Ni content > 0.6) cathode materials, porous Zirconium based metalorganic f...To effectively alleviate the surface structure degradation caused by electrolyte corrosion and transition metal(TM) dissolution for Ni-rich(Ni content > 0.6) cathode materials, porous Zirconium based metalorganic frameworks(Zr-MOFs, UiO-66) material is utilized herein as a positive electrode additive. UiO-66 owns tunable attachment sites and strong binding affinity, making itself an efficient defluorination agent to suppress the undesirable reactions caused by fluorine species. Besides, it can also relieve TMs dissolution and block the migration of TMs toward anode side since it’s a multifarious metal ions adsorbent,realizing both cathode and anode interface protection. Benefiting from these advantages, the UiO-66 assistant Ni-rich cathode achieves superior cycling stability. Particularly in full cell, the positive effects of this multifunctional additive are more pronounced than in the half-cell, that is after 400 cycles at 2 C,the capacity retention has doubled with the addition of UiO-66. More broadly, this unique application of functional additive provides new insight into the degradation mechanism of layered cathode materials and offers a new avenue to develop high-energy density batteries.展开更多
Boosting the interfacial stability between electrolyte and Li-rich cathode material at high operating voltage is vital important to enhance the cycling stability of Li-rich cathode materials for high-performance Li-io...Boosting the interfacial stability between electrolyte and Li-rich cathode material at high operating voltage is vital important to enhance the cycling stability of Li-rich cathode materials for high-performance Li-ion batteries.In this work,vinyltrimethylsilane as a new type of organic silicon electrolyte additive is studied to address the interfacial instability of Li-rich cathode material at high operating voltage.The cells using vinyltrimethylsilane additive shows the high capacity retention of 73.9%after 300 cycles at 1 C,whereas the cells without this kind of additive only have the capacity retention of 58.9%.The improvement of stability is mainly attributed to the additive helping to form a more stable surface film for Li-rich cathode material,thus avoiding direct contact between the electrolyte and the cathode material,slowing down the dissolution of metal ions and the decomposition of the electrolyte under high operating voltage.Our findings in this work shed some light on the design of stable cycling performance of Li-rich cathode toward advanced Li-ion batteries.展开更多
A double fluid model for a liquid jet surrounded by a coaxial gas stream was constructed. The interfacial stability of the model was studied by Chebyshev pseudospectral method for different basic velocity profiles. Th...A double fluid model for a liquid jet surrounded by a coaxial gas stream was constructed. The interfacial stability of the model was studied by Chebyshev pseudospectral method for different basic velocity profiles. The physical variables were mapped into computational space using a nonlinear coordinates transformation. The general eigenvalues of the dispersion relation obtained are solved by QZ method, and the basic characteristics and their dependence on the flow parameters are analyzed.展开更多
NASICON-structured Na_(3)Zr_(2)Si_(2)PO_(12)(NZSP)has been considered as one of the ideal electrolytes for all-solid-state sodium metal batteries(ASSSB).However,the practical application of NZSP-based ASSSB is hindere...NASICON-structured Na_(3)Zr_(2)Si_(2)PO_(12)(NZSP)has been considered as one of the ideal electrolytes for all-solid-state sodium metal batteries(ASSSB).However,the practical application of NZSP-based ASSSB is hindered by the low ionic conductivity and large interfacial resistance caused by the poor contact between NZSP and Na metal.Herein,the introduction of Fe_(2)O_(3) not only improves ionic conductivity and reduces activation energy by the doping of Fe^(3+)in the crystal structure of NZSP,but also reduces the interfacial resistance and enhances interface stability between NZSP and Na metal anode.The synergistic effects significantly enhance the cycling stability,rate capability,and critical current density of the symmetrical solid-state cells.The interfacial reaction mechanism indicates that Fe3+in the interface is reduced Fe2+by Na anode,which effectively even the electric-filed distribution and suppresses the dendrite growth.Consequently,the symmetric solid-state cells exhibit stable cycling performance for 1,500 h at 0.1 mA·cm^(−1)/0.1 mA·h·cm^(−1) and over 900 h at 0.2 mA·cm^(−1)/0.2 mA·h·cm^(−1).The Na|NZSP-0.075%Fe_(2)O_(3)|Na_(2)FePO_(4)F solid-state full cells display high capacity retention of 94.2%after 100 cycles at 0.5 C.The stable interface of NZSP/Na and improved ionic conductivity contribute to excellent electrochemical performance,which accelerates the practical application of ASSSB.展开更多
Extending the charging voltage of LiCoO_(2)(LCO)is an ongoing and promising approach to increase its energy density.However,the main challenge of the approach lies in the insuperable cathodic interfacial processes at ...Extending the charging voltage of LiCoO_(2)(LCO)is an ongoing and promising approach to increase its energy density.However,the main challenge of the approach lies in the insuperable cathodic interfacial processes at high voltage,which leads to rapid failure both in the performance and structure of the LCO cathode.Herein,a Li_(2)CO_(3)-based additive was prepared by a simple sand-milling method,enabling a low electrochemical decomposition voltage<4.6 V from commonly>4.8 V,stabilizing the interface of the LCO cathode at 4.6 V.The decomposition of Li_(2)CO_(3)provides extra Li^(+)and CO_(2)to supplement the Li consumption required in the initial irreversible interfacial reactions and rapidly form a uniform and stable cathode electrolyte interphase layer(less organic and more inorganic components)on the LCO cathode by reducing CO_(2).Thus,the phase transformation and the emergence of high-valent Co ions on the surface of LCO at 4.6 V high voltage were inhibited.Thanks to this,with 2%Li_(2)CO_(3)-based additive,the capacity retention of commercial LCO at a high voltage of 4.6 V at 0.5 C for 100 cycles was improved from 59.3%to 79.3%.This work improves the high-voltage stability of LCO and provides a new idea for realizing the high-voltage operation of batteries.展开更多
Ni-rich layered oxides(LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2))show great potential in long-range and low-cost lithiumion batteries.However,due to the high surface sensitivity,their practical application is hindered by inte...Ni-rich layered oxides(LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2))show great potential in long-range and low-cost lithiumion batteries.However,due to the high surface sensitivity,their practical application is hindered by interfacial instability with electrolytes under high voltage for long cyclic life.Herein,by combining both firstprinciple calculations and time-of-flight secondary ion mass spectrometry(TOF-SIMS),a novel surface fluorinated reconstruction(SFR)mechanism is proposed to improve the interfacial stability under high voltage,which could effectively regulate the surface fluoride species to desensitize the LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)interface.We demonstrate here that by tuning the ratio of fluoride species,the LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)/Li battery could achieve excellent long-term and high voltage performance(163.5 mA h g^(-1)at 0.5 C for 300 cycles under 4.4 V),while the controlled sample decayed to 125.4 mA h g^(-1)after 300 cycles.Moreover,the favorable cross-talk effect induced by SFR further facilitates the incorporation of suitable amounts of Ni ions into the construction of stable solid electrolyte interface(SEI)layer for anode surface.Therefore,the ultra-long cycling stability under high voltage can be achieved by the robust cathode/electrolyte and Li/electrolyte interfaces,which results in excellent interfacial stability after long cycling.This work provides new insights into the surface design of cathode materials and improves the stability of the electrode-electrode interface under high voltage.展开更多
Cycle stability and thermal safety are critical to the commercialization of nickel-rich layered materials,yet whether there is a potential correlation between these two factors is still controversial. Herein, the rela...Cycle stability and thermal safety are critical to the commercialization of nickel-rich layered materials,yet whether there is a potential correlation between these two factors is still controversial. Herein, the relationship between the cycle stability and thermal stability of nickel-rich cathode materials have been systematically studied through five different calcination temperatures of Li[NiCoMn]O(NCM83) cathode materials. The research results confirm that the cycle stability and thermal safety of nickel-rich cathode materials do not necessarily show a positive correlation. Actually, with the calcination temperature elevated, the thermal stability of the NCM83 is enhanced, while the cycle stability is degraded. This opposite correlation is not commonly reported in previous literatures. In this work, systematical characterizations demonstrate that under the experimental conditions, the capacity retention of NCM83 is mainly determined by the Li/Ni cation disorder and H2-H3 irreversible phase transition,which is optimal at lower calcination temperature. Meanwhile, the thermal stability is mainly impacted by thermal expansion characteristics and interfacial stability of cathode material, and it is dramatically improved by the mechanical strength of the secondary particles reinforced at high calcinated temperature. This study provides some new insights on understanding and designing of the high-energy cathode materials with long cycle-life and superior safety.展开更多
The interfacial compatibility of composite membrane is an important factor to its structural stability, andseparation performance. In this study, poly （ether sulfone） （PES） support layer was first hydrophilically ...The interfacial compatibility of composite membrane is an important factor to its structural stability, andseparation performance. In this study, poly （ether sulfone） （PES） support layer was first hydrophilically modified with poly（vinyl alcohol） （PVA） via surface segregation during the phase inversion process. Gelatin （GE） was then cast on the PVA-modified PES support layer as the active layer followed by crosslinking to fabricate composite membranes for ethanol dehydration. The enrichment of PVA on the surface of support layer improved interfacial compatibility of the as-prepared GE/PVA-PES composite membrane. The water contact angle measurement and X-ray photoelectron spectroscopy （XPS） data confirmed the surface segregation of PVA with a surface coverage density of -80%. T-peel test showed that the maxima/force to separate the support layer and the active layer was enhanced by 3 times compared with the GE/PES membrane. The effects of PVA content in the support layer, crosslinking of GE active layer and operating parameters on the pervaporative dehydration performance were investigated. The operational stability of the composite membrane was tested by immersing the membrane in ethanol aqueous solution for a period of time. Stable pervaporation performance for dehydration of 90% ethanol solution was obtained for GE/PVA-PES membrane with a separation factor of -60 and a permeation flux of -1910 g.m^-2.h1 without peeling over 28 days immersion.展开更多
Layered LiCoO_(2)(LCO)acts as a dominant cathode material for lithium-ion batteries(LIBs)in 3C products because of its high compacted density and volumetric energy density.Although improving the high cutoff voltage is...Layered LiCoO_(2)(LCO)acts as a dominant cathode material for lithium-ion batteries(LIBs)in 3C products because of its high compacted density and volumetric energy density.Although improving the high cutoff voltage is an effective strategy to increase its capacity,such behavior would trigger rapid capacity decay due to the surface or/and structure degradation.Herein,we propose a bi-functional surface strategy involving constructing a robust spinel-like phase coating layer with great integrity and compatibility to LiCoO_(2) and modulating crystal lattice by anion and cation gradient co-doping at the subsurface.As a result,the modified LiCoO_(2)(AFM-LCO)shows a capacity retention of 80.9%after 500 cycles between 3.0and 4.6 V.The Al,F,Mg enriched spinel-like phase coating layer serves as a robust physical barrier to effectively inhibit the undesired side reactions between the electrolyte and the cathode.Meanwhile,the Al,F,Mg gradient co-doping significantly enhances the surficial structure stability,suppresses Co dissolution and oxygen release,providing a stable path for Li-ions mobility all through the long-term cycles.Thus,the surface bi-functional strategy is an effective method to synergistically improve the electrochemical performances of LCO at a high cut-off voltage of 4.6 V.展开更多
1,3-dioxolane （DOL） was originally used to pretreat a lithium metal electrode to improve its interfacial characteristics. Electrochemical impedance spectra （EIS） meastLrements revealed that, after the DOL pretreat...1,3-dioxolane （DOL） was originally used to pretreat a lithium metal electrode to improve its interfacial characteristics. Electrochemical impedance spectra （EIS） meastLrements revealed that, after the DOL pretreatment, the lithium electrode had better interfacial stability during immersion in electrolyte and as repeated charge/discharge cycles. It was proved by SEaM that the pretreated one has smoother morphology and less dendrite after repeated charge/discharge cycles. Consequentially, benefiting from the better interface characteristics of the lithium electrode, the rechargeable lithium cell with a DOL-pretreated lithium anode had the obviously enhanced discharging performance and better cyclability.展开更多
The pursuit of safer and high-performance lithium-ion batteries(LIBs)has triggered extensive research activities on solid-state batteries,while challenges related to the unstable electrode-electrolyte interface hinder...The pursuit of safer and high-performance lithium-ion batteries(LIBs)has triggered extensive research activities on solid-state batteries,while challenges related to the unstable electrode-electrolyte interface hinder their practical implementation.Polymer has been used extensively to improve the cathode-electrolyte interface in garnet-based all-solid-state LIBs(ASSLBs),while it introduces new concerns about thermal stability.In this study,we propose the incorporation of a multi-functional flame-retardant triphenyl phos-phate additive into poly(ethylene oxide),acting as a thin buffer layer between LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)cathode and garnet electro-lyte.Through electrochemical stability tests,cycling performance evaluations,interfacial thermal stability analysis and flammability tests,improved thermal stability(capacity retention of 98.5%after 100 cycles at 60℃,and 89.6%after 50 cycles at 80℃)and safety characteristics(safe and stable cycling up to 100℃)are demonstrated.Based on various materials characterizations,the mechanism for the improved thermal stability of the interface is proposed.The results highlight the potential of multi-functional flame-retardant additives to address the challenges associated with the electrode-electrolyte interface in ASSLBs at high temperature.Efficient thermal modification in ASSLBs operating at elevated temperatures is also essential for enabling large-scale energy storage with safety being the primary concern.展开更多
Solid-state electrolytes with high oxidation stability are crucial for achieving high power density allsolid-state lithium batteries.Halide electrolytes are promising candidates due to their outstanding compatibility ...Solid-state electrolytes with high oxidation stability are crucial for achieving high power density allsolid-state lithium batteries.Halide electrolytes are promising candidates due to their outstanding compatibility with cathode materials and high Li^(+)conductivity.However,the electrochemical stability of chloride electrolytes is still limited,leaving them unsuitable for ultrahigh voltage operation.Besides,chemical compatibility issue between sulfide and halide electrolytes affects the electrochemical performance of all-solid-state batteries.Herein,Li-ion conductor Li_(3+x)InCl_(6-x)O_(x) is designed to address these challenges.Li_(3.25)InCl_(5.75)O_(0.25)shows a Li-ion conductivity of 0.90 mS cm^(-1)at room temperature,a high onset oxidation voltage of 3.84 V,fewer by-products at ultrahigh operation voltage,and good chemical compatibility with Li_(5.5)PS_(4.5)Cl_(1.5).The Li_(3.25)InCl_(5.75)O_(0.25)@LiNi_(0.7)Co_(0.1)Mn_(0.2)O_(2)-Li_(3.25)InCl_(5.75)O_(0.25)-VGCF/Li_(3.25)InCl_(5.75)O_(0.25)/Li_(5.5)PS_(4.5)Cl_(1.5)/Li-In battery delivers good electrochemical performances at high operating voltage.This work provides a simple,economical,and effective strategy for designing high-voltage all-solid-state electrolytes.展开更多
The stress-induced phase transformation in incompressible materials and the interfacial stability of multi-phase deformation were studied. The existence of multi-phase deformation was determined through exploring whet...The stress-induced phase transformation in incompressible materials and the interfacial stability of multi-phase deformation were studied. The existence of multi-phase deformation was determined through exploring whether the material would lose the strong ellipticity at some deformation gradient. Then, according to the stability criterion which is based on a quasi-static approach, the stability of the multi-phase deformation in incompressible materials was investigated by studying the growth/decay behaviour of the interface in the undeformed configuration when it is perturbed. At last, the way to define multi-phase deformation in incompressible materials was concluded and testified by a corresponding numerical example.展开更多
The crux of molybdenum/Fe-base alloy welded joint is embrittlement and consequently deteriorated strength.The current researches just attribute it to brittle intermetallic compound inside the weld.However,no brittle p...The crux of molybdenum/Fe-base alloy welded joint is embrittlement and consequently deteriorated strength.The current researches just attribute it to brittle intermetallic compound inside the weld.However,no brittle phase continuously precipitates at the fracture location of the molybdenum/Kovar alloy electron beam welded joint,meaning that the unstable phase interface is the real fundamental reason for the brittleness of joint,instead of the phases themselves.Noncoherent interfaces are formed betweenα-Mo and eutectoidα-Fe+μ(Fe3Mo2)deriving from solid-state phase transition.To optimize interfacial coherence and stabilize the interface,CoCrCuFeNi high entropy alloy is added into the weld.The new interfaces betweenα-Mo and eutectic face-centered cubic(fcc)+laves are transformed into coherent interfaces.σ(FeCr)nanoparticles precipitate atα-Mo/fcc interface,indicating the decreased interfacial energy and more stable interface.The tensile strength of the joint is increased from 262 to 366 MPa.The present work provides guidance for optimizing welding quality between molybdenum and Fe-base alloy.展开更多
To address the limitations of contemporary lithium-ion batteries,particularly their low energy density and safety concerns,all-solid-state lithium batteries equipped with solid-state electrolytes have been identified ...To address the limitations of contemporary lithium-ion batteries,particularly their low energy density and safety concerns,all-solid-state lithium batteries equipped with solid-state electrolytes have been identified as an up-and-coming alternative.Among the various SEs,organic–inorganic composite solid electrolytes(OICSEs)that combine the advantages of both polymer and inorganic materials demonstrate promising potential for large-scale applications.However,OICSEs still face many challenges in practical applications,such as low ionic conductivity and poor interfacial stability,which severely limit their applications.This review provides a comprehensive overview of recent research advancements in OICSEs.Specifically,the influence of inorganic fillers on the main functional parameters of OICSEs,including ionic conductivity,Li+transfer number,mechanical strength,electrochemical stability,electronic conductivity,and thermal stability are systematically discussed.The lithium-ion conduction mechanism of OICSE is thoroughly analyzed and concluded from the microscopic perspective.Besides,the classic inorganic filler types,including both inert and active fillers,are categorized with special emphasis on the relationship between inorganic filler structure design and the electrochemical performance of OICSEs.Finally,the advanced characterization techniques relevant to OICSEs are summarized,and the challenges and perspectives on the future development of OICSEs are also highlighted for constructing superior ASSLBs.展开更多
All-solid-state lithium batteries(ASSLBs)are regarded as the representative of next-generation energy storage technology.It can solve the flammability hazard of liquid lithium batteries and their theoretical energy de...All-solid-state lithium batteries(ASSLBs)are regarded as the representative of next-generation energy storage technology.It can solve the flammability hazard of liquid lithium batteries and their theoretical energy density can reach exceeding 500 Wh·kg^(-1).Silicon is one of the most attractive anode materials for high-energy ASSLBs because of its high theoretical capacity and low working potential.However,Si anode faces two key problems in practical applications.Firstly,the side reaction between Si and sulfide-based solid-state electrolytes is serious,which can form unstable interfacial phases,significantly increase interfacial impedance and deplete active lithium.Secondly,electrical/ionic contact loss caused by volume change of Si electrode during lithiation/delithiation process results in significant initial capacity loss and poor cycling stability.For this reason,a simple liquidphase approach was taken to form Li_(x)SiS_(y)layer-coated Si nanoparticles in-situ,and composite electrodes were prepared in this way.High initial coulombic efficiency(ICE)and stable cyclability for sulfide-based ASSLBs can be achieved.The results show that the Si@Li_(x)SiS_(y)-Li_(3)PS_(4)-C composite electrode exhibits a higher ICE of 77.5%at 0.13 mA·cm^(-2)compared to that of 55.9%for Si-Li_(3)PS_(4)-C electrode and a more stable cycling performance without external pressure.This indicates that the direct contact between Si and Li_(3)PS_(4)electrolyte is effectively blocked by coating with a Li_(x)SiS_(y)layer.Stable interface between Si and Li_(3)PS_(4)electrolyte can be obtained and prevent the side reactions between them.Both the stable interface and partial prelithiation of Si electrode is favorable for high initial reversibility.At the same time the presence of the coating layer reduces the mechanical stress due to the volume change of the Si particles and ensures a good stress relief.The greatly improved interfacial stability and favorable stress release ensured by the conformal coating layer can thus lead to good electrochemical performance of Si electrode in ASSLBs.展开更多
Flame-retardant gel polymer electrolyte(FRGPE)with high ionic conductivity and practical safety is essential for the next generation of high energy density sodium metal batteries(SMBs).However,they suffer from serious...Flame-retardant gel polymer electrolyte(FRGPE)with high ionic conductivity and practical safety is essential for the next generation of high energy density sodium metal batteries(SMBs).However,they suffer from serious side reactions and insufficient interfacial stability against sodium metal anode,causing severe performance degradation and even safety issues.Herein,to address these challenges,a fluoroethylene carbonate(FEC)additive confined metal-organic framework(MOF)-based composite gel(AC-MCG)interlayer was constructed upon sodium anode through a facile in-situ UV-induced photopolymerization.The FEC confined in AC-MCG induces the formation of NaF-rich inorganic solid-electrolyte interphase,effectively eliminating the side reactions between the FRGPE and sodium metal anode.Moreover,the MOF with ordered nanochannels can homogenize Na^(+)flux during the plating process and also endow the AC-MCG interlayer with high mechanical strength,thus sufficiently suppressing the growth of sodium dendrites.Benefitting from these merits of the AC-MCG interlayer,a high critical current density of 2.0 mA cm^(-2)and a long-term cycling life for over 4200 h at 0.1 mA cm^(-2)are achieved for the Na/Na symmetric cells.Besides,the solid-state SMBs paired with the constructed AC-MCG interlayer also demonstrated considerable electrochemical performance and practical safety.展开更多
Solid polymer electrolytes(SPEs)are considered one of the most promising materials for all-solid-state lithium metal batteries(ASSLMBs)due to their facile processability.However,developing SPEs with both high ionic co...Solid polymer electrolytes(SPEs)are considered one of the most promising materials for all-solid-state lithium metal batteries(ASSLMBs)due to their facile processability.However,developing SPEs with both high ionic conductivity and interfacial stability remains a challenge.Here,a donor-acceptor(D-A)like solid plasticizer,tris(pentafluorophenyl)borane(TPFPB),containing electron-rich F atoms and electrondeficient B sites,was introduced to regulate the ion transport behavior and interfacial chemistry of polyethylene oxide(PEO)-based SPEs.Owing to the multiple ion-dipole interactions(F Li^(+)TFSI^(-)and B TFSI^(-)Li^(+))between the TPFPB molecule and Li salts,a multimodal electrolyte environment featuring more free Li^(+)and trapped TFSI^(-)anions was generated,which cooperates with the reduced crystallinity of PEO,significantly facilitating the rapid migration of Li^(+).More importantly,TPFPB tends to be preferentially reduced to form a stable inorganic-rich solid electrolyte interphase on the Li-metal anode,ensuring uniform Li plating/stripping behavior.Thus,the TPFPB-modulated SPEs system achieves a high Li^(+)conductivity of 0.74 m S cm^(-1)and effectively suppresses dendrite growth,which enables a long-cycle dendrite-free Li/Li symmetric cell for over 5000 h,and remarkable electrochemical performance has been further validated in operational ASSLMBs.The findings in this work would inspire efforts to develop highperformance SPEs for all-solid-state alkali-metal batteries.展开更多
基金Financial supports from the National Natural Science Foundation of China (51575030, 51532002 and 51872027)Beijing Natural Science Foundation (L172023)National Basic Research Program of China (2017YFE0113500)。
文摘The solid-state lithium battery is considered as an ideal next-generation energy storage device owing to its high safety,high energy density and low cost.However,the poor ionic conductivity of solid electrolyte and low interfacial stability has hindered the application of solid-state lithium battery.Here,a flexible polymer/garnet solid electrolyte is prepared with poly(ethylene oxide),poly(vinylidene fluoride),Li6.75La3 Zr1.75Ta0.25O12,lithium bis(trifluoromethanesulfonyl)imide and oxalate,which exhibits an ionic conductivity of 2.0 ×10^(-4) S cm^(-1) at 55℃,improved mechanical property,wide electrochemical window(4.8 V vs.Li/Li+),enhanced thermal stabilities.Tiny acidic OX was introduced to inhibit the alkalinity reactions between Li6.75La3 Zr1.75Ta0.25O12 and poly(vinylidene fluoride).In order to improve the interfacial stability between cathode and electrolyte,an Al2 O3@LiNi0.5Co0.2Mn0.3O2 based composite cathode framework is also fabricated with poly(ethylene oxide) polymer and lithium salt as additives.The solid-state lithium battery assembled with polymer/garnet solid electrolyte and composite cathode framework demonstrates a high initial discharge capacity of 150.6 mAh g^(-1) and good capacity retention of 86.7% after 80 cycles at 0.2 C and 55℃,which provides a promising choice for achieving the stable electrode/electrolyte interfacial contact in solid-state lithium batteries.
基金support by National Natural Science Foundation of China(51271205,50801070)‘‘Project of Science and Technology Plan’’by Qingyuan city(DZXQY052,2018C005,2019A026)+2 种基金Project of results transformation achievement fund by Sun Yat-sen University(31000-18843232)‘‘Tian’e Plan’’by Huizhou city(20170220011822281,20170220085037390)the Scientifc Technology Project of Guangzhou City(202103000003).
文摘The stability of Zn anode in various Znbased energy storage devices is the key problem to be solved.Herein,aromatic aldehyde additives are selected to modulate the interface reactions between the Zn anode and electrolyte.Through comprehensively considering electrochemical measurements,DFT calculations and FEA simulations,novel mechanisms of one kind of aromatic aldehyde,veratraldehyde in inhibiting Zn dendrite/by-products can be obtained.This additive prefers to absorb on the Zn surface than H_(2)O molecules and Zn^(2+),while competes with hydrogen evolution reaction and Zn plating/stripping proces s via redox reactions,thus preventing the decomposition of active H_(2)O near the interface and uncontrollable Zn dendrite growth via a synactic absorption-competition mechanism.As a result,Zn-Zn symmetric cells with the veratraldehyde additive realize an excellent cycling life of 3200 h under 1 mA cm^(-2)/1 mAh cm^(-2)and over 800 h even under 5 mA cm^(-2)/5 mAh cm^(-2).Moreover,Zn-Ti and Zn-MnO_(2)cells with the veratraldehyde additive both obtain elevated performance than that with pure ZnSO_(4)electrolyte.Finally,two more aromatic aldehyde additives are chosen to prove their universality in stabilizing Zn anodes.
基金National Key R&D Program of China(2016YFB0100301)the National Natural Science Foundation of China(21875022,51802020,U1664255)+1 种基金Beijing Institute of Technology Research Fund Program for Young ScholarsYoung Elite Scientists Sponsorship Program by CAST(2018QNRC001)。
文摘To effectively alleviate the surface structure degradation caused by electrolyte corrosion and transition metal(TM) dissolution for Ni-rich(Ni content > 0.6) cathode materials, porous Zirconium based metalorganic frameworks(Zr-MOFs, UiO-66) material is utilized herein as a positive electrode additive. UiO-66 owns tunable attachment sites and strong binding affinity, making itself an efficient defluorination agent to suppress the undesirable reactions caused by fluorine species. Besides, it can also relieve TMs dissolution and block the migration of TMs toward anode side since it’s a multifarious metal ions adsorbent,realizing both cathode and anode interface protection. Benefiting from these advantages, the UiO-66 assistant Ni-rich cathode achieves superior cycling stability. Particularly in full cell, the positive effects of this multifunctional additive are more pronounced than in the half-cell, that is after 400 cycles at 2 C,the capacity retention has doubled with the addition of UiO-66. More broadly, this unique application of functional additive provides new insight into the degradation mechanism of layered cathode materials and offers a new avenue to develop high-energy density batteries.
基金supported partially by State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(Nos.LAPS_(2)1004,LAPS_(2)02114)National Natural Science Foundation of China(Nos.52272200,51972110,52102245 and 52072121)+6 种基金Beijing Science and Technology Project(No.Z211100004621010)Beijing Natural Science Foundation(Nos.2222076,2222077)Hebei Natural Science Foundation(No.E2022502022)Huaneng Group Headquarters Science and Technology Project(No.HNKJ20-H88)2022 Strategic Research Key Project of Science and Technology Commission of the Ministry of Education,China Postdoctoral Science Foundation(No.2022M721129)the Fundamental Research Funds for the Central Universities(Nos.2022MS030,2021MS028,2020MS023,2020MS028)the NCEPU"Double First-Class"Program and the State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(No.LAPS22005).
文摘Boosting the interfacial stability between electrolyte and Li-rich cathode material at high operating voltage is vital important to enhance the cycling stability of Li-rich cathode materials for high-performance Li-ion batteries.In this work,vinyltrimethylsilane as a new type of organic silicon electrolyte additive is studied to address the interfacial instability of Li-rich cathode material at high operating voltage.The cells using vinyltrimethylsilane additive shows the high capacity retention of 73.9%after 300 cycles at 1 C,whereas the cells without this kind of additive only have the capacity retention of 58.9%.The improvement of stability is mainly attributed to the additive helping to form a more stable surface film for Li-rich cathode material,thus avoiding direct contact between the electrolyte and the cathode material,slowing down the dissolution of metal ions and the decomposition of the electrolyte under high operating voltage.Our findings in this work shed some light on the design of stable cycling performance of Li-rich cathode toward advanced Li-ion batteries.
文摘A double fluid model for a liquid jet surrounded by a coaxial gas stream was constructed. The interfacial stability of the model was studied by Chebyshev pseudospectral method for different basic velocity profiles. The physical variables were mapped into computational space using a nonlinear coordinates transformation. The general eigenvalues of the dispersion relation obtained are solved by QZ method, and the basic characteristics and their dependence on the flow parameters are analyzed.
基金This work was financially supported by the National Natural Science Foundation of China(22179071 and 52072217)the National Key R&D Program of China(2022YFB3807700)+3 种基金the Hubei Natural Science Foundation for Distinguished Young Scholars(2023AFA089)the Hubei Natural Science Foundation Innovation Group Project(2022CFA020)the Major Technological Innovation Project of Hubei Science and Technology Department(2019AAA164)Joint Funds of the Hubei Natural Science Foundation Innovation and Development(2022CFD034).
文摘NASICON-structured Na_(3)Zr_(2)Si_(2)PO_(12)(NZSP)has been considered as one of the ideal electrolytes for all-solid-state sodium metal batteries(ASSSB).However,the practical application of NZSP-based ASSSB is hindered by the low ionic conductivity and large interfacial resistance caused by the poor contact between NZSP and Na metal.Herein,the introduction of Fe_(2)O_(3) not only improves ionic conductivity and reduces activation energy by the doping of Fe^(3+)in the crystal structure of NZSP,but also reduces the interfacial resistance and enhances interface stability between NZSP and Na metal anode.The synergistic effects significantly enhance the cycling stability,rate capability,and critical current density of the symmetrical solid-state cells.The interfacial reaction mechanism indicates that Fe3+in the interface is reduced Fe2+by Na anode,which effectively even the electric-filed distribution and suppresses the dendrite growth.Consequently,the symmetric solid-state cells exhibit stable cycling performance for 1,500 h at 0.1 mA·cm^(−1)/0.1 mA·h·cm^(−1) and over 900 h at 0.2 mA·cm^(−1)/0.2 mA·h·cm^(−1).The Na|NZSP-0.075%Fe_(2)O_(3)|Na_(2)FePO_(4)F solid-state full cells display high capacity retention of 94.2%after 100 cycles at 0.5 C.The stable interface of NZSP/Na and improved ionic conductivity contribute to excellent electrochemical performance,which accelerates the practical application of ASSSB.
基金supported by the National Key Research and Development Program of China(2022YFB2502103)the Xiamen Science and Technology Project(No.3502Z20231057)+2 种基金the National Natural Science Foundation of China(No.22288102,No.22279107,No.22309153)the Fujian Provincial Natural Science Foundation of China(No.2024J01040)the Fundamental Research Funds for the Central Universities(No.20720230039)。
文摘Extending the charging voltage of LiCoO_(2)(LCO)is an ongoing and promising approach to increase its energy density.However,the main challenge of the approach lies in the insuperable cathodic interfacial processes at high voltage,which leads to rapid failure both in the performance and structure of the LCO cathode.Herein,a Li_(2)CO_(3)-based additive was prepared by a simple sand-milling method,enabling a low electrochemical decomposition voltage<4.6 V from commonly>4.8 V,stabilizing the interface of the LCO cathode at 4.6 V.The decomposition of Li_(2)CO_(3)provides extra Li^(+)and CO_(2)to supplement the Li consumption required in the initial irreversible interfacial reactions and rapidly form a uniform and stable cathode electrolyte interphase layer(less organic and more inorganic components)on the LCO cathode by reducing CO_(2).Thus,the phase transformation and the emergence of high-valent Co ions on the surface of LCO at 4.6 V high voltage were inhibited.Thanks to this,with 2%Li_(2)CO_(3)-based additive,the capacity retention of commercial LCO at a high voltage of 4.6 V at 0.5 C for 100 cycles was improved from 59.3%to 79.3%.This work improves the high-voltage stability of LCO and provides a new idea for realizing the high-voltage operation of batteries.
基金supported by the National Natural Science Foundation of China(22209012,52072036)the fellowship of China Postdoctoral Science Foundation(2020M680374)。
文摘Ni-rich layered oxides(LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2))show great potential in long-range and low-cost lithiumion batteries.However,due to the high surface sensitivity,their practical application is hindered by interfacial instability with electrolytes under high voltage for long cyclic life.Herein,by combining both firstprinciple calculations and time-of-flight secondary ion mass spectrometry(TOF-SIMS),a novel surface fluorinated reconstruction(SFR)mechanism is proposed to improve the interfacial stability under high voltage,which could effectively regulate the surface fluoride species to desensitize the LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)interface.We demonstrate here that by tuning the ratio of fluoride species,the LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)/Li battery could achieve excellent long-term and high voltage performance(163.5 mA h g^(-1)at 0.5 C for 300 cycles under 4.4 V),while the controlled sample decayed to 125.4 mA h g^(-1)after 300 cycles.Moreover,the favorable cross-talk effect induced by SFR further facilitates the incorporation of suitable amounts of Ni ions into the construction of stable solid electrolyte interface(SEI)layer for anode surface.Therefore,the ultra-long cycling stability under high voltage can be achieved by the robust cathode/electrolyte and Li/electrolyte interfaces,which results in excellent interfacial stability after long cycling.This work provides new insights into the surface design of cathode materials and improves the stability of the electrode-electrode interface under high voltage.
基金financially supported by the China Postdoctoral Science Foundation(2021M700396)the National Natural Science Foundation of China(52102206)the National Research Foundation of Republic of Korea(2021K2A9A2A06044652)。
文摘Cycle stability and thermal safety are critical to the commercialization of nickel-rich layered materials,yet whether there is a potential correlation between these two factors is still controversial. Herein, the relationship between the cycle stability and thermal stability of nickel-rich cathode materials have been systematically studied through five different calcination temperatures of Li[NiCoMn]O(NCM83) cathode materials. The research results confirm that the cycle stability and thermal safety of nickel-rich cathode materials do not necessarily show a positive correlation. Actually, with the calcination temperature elevated, the thermal stability of the NCM83 is enhanced, while the cycle stability is degraded. This opposite correlation is not commonly reported in previous literatures. In this work, systematical characterizations demonstrate that under the experimental conditions, the capacity retention of NCM83 is mainly determined by the Li/Ni cation disorder and H2-H3 irreversible phase transition,which is optimal at lower calcination temperature. Meanwhile, the thermal stability is mainly impacted by thermal expansion characteristics and interfacial stability of cathode material, and it is dramatically improved by the mechanical strength of the secondary particles reinforced at high calcinated temperature. This study provides some new insights on understanding and designing of the high-energy cathode materials with long cycle-life and superior safety.
基金Supported by the New Century Excellent Talents in University(NCET-10-0623)National Natural Science Foundation for Distinguished Young Scholars(21125627)+1 种基金National Basic Research Program of China(2009CB623404)State Key Laboratory for Modification of Chemical Fibers and Polymer Materials(Dong Hua University)
文摘The interfacial compatibility of composite membrane is an important factor to its structural stability, andseparation performance. In this study, poly （ether sulfone） （PES） support layer was first hydrophilically modified with poly（vinyl alcohol） （PVA） via surface segregation during the phase inversion process. Gelatin （GE） was then cast on the PVA-modified PES support layer as the active layer followed by crosslinking to fabricate composite membranes for ethanol dehydration. The enrichment of PVA on the surface of support layer improved interfacial compatibility of the as-prepared GE/PVA-PES composite membrane. The water contact angle measurement and X-ray photoelectron spectroscopy （XPS） data confirmed the surface segregation of PVA with a surface coverage density of -80%. T-peel test showed that the maxima/force to separate the support layer and the active layer was enhanced by 3 times compared with the GE/PES membrane. The effects of PVA content in the support layer, crosslinking of GE active layer and operating parameters on the pervaporative dehydration performance were investigated. The operational stability of the composite membrane was tested by immersing the membrane in ethanol aqueous solution for a period of time. Stable pervaporation performance for dehydration of 90% ethanol solution was obtained for GE/PVA-PES membrane with a separation factor of -60 and a permeation flux of -1910 g.m^-2.h1 without peeling over 28 days immersion.
基金supported by the National Natural Science Foundation of China(22075170,52072233)the Beijing National Laboratory for Condensed Matter Physics。
文摘Layered LiCoO_(2)(LCO)acts as a dominant cathode material for lithium-ion batteries(LIBs)in 3C products because of its high compacted density and volumetric energy density.Although improving the high cutoff voltage is an effective strategy to increase its capacity,such behavior would trigger rapid capacity decay due to the surface or/and structure degradation.Herein,we propose a bi-functional surface strategy involving constructing a robust spinel-like phase coating layer with great integrity and compatibility to LiCoO_(2) and modulating crystal lattice by anion and cation gradient co-doping at the subsurface.As a result,the modified LiCoO_(2)(AFM-LCO)shows a capacity retention of 80.9%after 500 cycles between 3.0and 4.6 V.The Al,F,Mg enriched spinel-like phase coating layer serves as a robust physical barrier to effectively inhibit the undesired side reactions between the electrolyte and the cathode.Meanwhile,the Al,F,Mg gradient co-doping significantly enhances the surficial structure stability,suppresses Co dissolution and oxygen release,providing a stable path for Li-ions mobility all through the long-term cycles.Thus,the surface bi-functional strategy is an effective method to synergistically improve the electrochemical performances of LCO at a high cut-off voltage of 4.6 V.
基金This project was financially supported by the Foundation of Science-Technology Research Program of Guangdong Prov-ince, China (No. 2003C105006).
文摘1,3-dioxolane （DOL） was originally used to pretreat a lithium metal electrode to improve its interfacial characteristics. Electrochemical impedance spectra （EIS） meastLrements revealed that, after the DOL pretreatment, the lithium electrode had better interfacial stability during immersion in electrolyte and as repeated charge/discharge cycles. It was proved by SEaM that the pretreated one has smoother morphology and less dendrite after repeated charge/discharge cycles. Consequentially, benefiting from the better interface characteristics of the lithium electrode, the rechargeable lithium cell with a DOL-pretreated lithium anode had the obviously enhanced discharging performance and better cyclability.
基金This work was supported by the Australian Research Council via Discovery Projects(Nos.DP200103315,DP200103332 and DP230100685)Linkage Projects(No.LP220200920).The authors acknowledge the Microscopy and Microanalysis Facility—John de Laeter Centre,Curtin University for the scientific and technical assistance of material characterizations.L.Zhao and C.Cao would like to acknowledge the PhD scholarship supported by BLACKSTONE Minerals Ltd.
文摘The pursuit of safer and high-performance lithium-ion batteries(LIBs)has triggered extensive research activities on solid-state batteries,while challenges related to the unstable electrode-electrolyte interface hinder their practical implementation.Polymer has been used extensively to improve the cathode-electrolyte interface in garnet-based all-solid-state LIBs(ASSLBs),while it introduces new concerns about thermal stability.In this study,we propose the incorporation of a multi-functional flame-retardant triphenyl phos-phate additive into poly(ethylene oxide),acting as a thin buffer layer between LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)cathode and garnet electro-lyte.Through electrochemical stability tests,cycling performance evaluations,interfacial thermal stability analysis and flammability tests,improved thermal stability(capacity retention of 98.5%after 100 cycles at 60℃,and 89.6%after 50 cycles at 80℃)and safety characteristics(safe and stable cycling up to 100℃)are demonstrated.Based on various materials characterizations,the mechanism for the improved thermal stability of the interface is proposed.The results highlight the potential of multi-functional flame-retardant additives to address the challenges associated with the electrode-electrolyte interface in ASSLBs at high temperature.Efficient thermal modification in ASSLBs operating at elevated temperatures is also essential for enabling large-scale energy storage with safety being the primary concern.
基金supported by the National Key Research and Development Program of China(2021YFB2500200)the National Natural Science Foundation of China(52177214,52222703)for supporting our workJiangsu Funding Program for Excellent Postdoctoral Talent for the support。
文摘Solid-state electrolytes with high oxidation stability are crucial for achieving high power density allsolid-state lithium batteries.Halide electrolytes are promising candidates due to their outstanding compatibility with cathode materials and high Li^(+)conductivity.However,the electrochemical stability of chloride electrolytes is still limited,leaving them unsuitable for ultrahigh voltage operation.Besides,chemical compatibility issue between sulfide and halide electrolytes affects the electrochemical performance of all-solid-state batteries.Herein,Li-ion conductor Li_(3+x)InCl_(6-x)O_(x) is designed to address these challenges.Li_(3.25)InCl_(5.75)O_(0.25)shows a Li-ion conductivity of 0.90 mS cm^(-1)at room temperature,a high onset oxidation voltage of 3.84 V,fewer by-products at ultrahigh operation voltage,and good chemical compatibility with Li_(5.5)PS_(4.5)Cl_(1.5).The Li_(3.25)InCl_(5.75)O_(0.25)@LiNi_(0.7)Co_(0.1)Mn_(0.2)O_(2)-Li_(3.25)InCl_(5.75)O_(0.25)-VGCF/Li_(3.25)InCl_(5.75)O_(0.25)/Li_(5.5)PS_(4.5)Cl_(1.5)/Li-In battery delivers good electrochemical performances at high operating voltage.This work provides a simple,economical,and effective strategy for designing high-voltage all-solid-state electrolytes.
基金Supported by National Natural Science Foundation of China(No.10272079)the Joint Grant from National Natural Science Foundation of China andthe Royal Society, UK(No.10511130192) .
文摘The stress-induced phase transformation in incompressible materials and the interfacial stability of multi-phase deformation were studied. The existence of multi-phase deformation was determined through exploring whether the material would lose the strong ellipticity at some deformation gradient. Then, according to the stability criterion which is based on a quasi-static approach, the stability of the multi-phase deformation in incompressible materials was investigated by studying the growth/decay behaviour of the interface in the undeformed configuration when it is perturbed. At last, the way to define multi-phase deformation in incompressible materials was concluded and testified by a corresponding numerical example.
基金supported by the National Natural Science Foundation of China(Grant No.52375322)the Key Special Projects of Aeroengine and Gas Turbine(Grant No.J2019-VII-0012-0154).
文摘The crux of molybdenum/Fe-base alloy welded joint is embrittlement and consequently deteriorated strength.The current researches just attribute it to brittle intermetallic compound inside the weld.However,no brittle phase continuously precipitates at the fracture location of the molybdenum/Kovar alloy electron beam welded joint,meaning that the unstable phase interface is the real fundamental reason for the brittleness of joint,instead of the phases themselves.Noncoherent interfaces are formed betweenα-Mo and eutectoidα-Fe+μ(Fe3Mo2)deriving from solid-state phase transition.To optimize interfacial coherence and stabilize the interface,CoCrCuFeNi high entropy alloy is added into the weld.The new interfaces betweenα-Mo and eutectic face-centered cubic(fcc)+laves are transformed into coherent interfaces.σ(FeCr)nanoparticles precipitate atα-Mo/fcc interface,indicating the decreased interfacial energy and more stable interface.The tensile strength of the joint is increased from 262 to 366 MPa.The present work provides guidance for optimizing welding quality between molybdenum and Fe-base alloy.
基金supported by the National Natural Science Foundation of China(Grant No.22075064,52302234,52272241)Zhejiang Provincial Natural Science Foundation of China under Grant No.LR24E020001+2 种基金Natural Science of Heilongjiang Province(No.LH2023B009)China Postdoctoral Science Foundation(2022M710950)Heilongjiang Postdoctoral Fund(LBH-Z21131),National Key Laboratory Projects(No.SYSKT20230056).
文摘To address the limitations of contemporary lithium-ion batteries,particularly their low energy density and safety concerns,all-solid-state lithium batteries equipped with solid-state electrolytes have been identified as an up-and-coming alternative.Among the various SEs,organic–inorganic composite solid electrolytes(OICSEs)that combine the advantages of both polymer and inorganic materials demonstrate promising potential for large-scale applications.However,OICSEs still face many challenges in practical applications,such as low ionic conductivity and poor interfacial stability,which severely limit their applications.This review provides a comprehensive overview of recent research advancements in OICSEs.Specifically,the influence of inorganic fillers on the main functional parameters of OICSEs,including ionic conductivity,Li+transfer number,mechanical strength,electrochemical stability,electronic conductivity,and thermal stability are systematically discussed.The lithium-ion conduction mechanism of OICSE is thoroughly analyzed and concluded from the microscopic perspective.Besides,the classic inorganic filler types,including both inert and active fillers,are categorized with special emphasis on the relationship between inorganic filler structure design and the electrochemical performance of OICSEs.Finally,the advanced characterization techniques relevant to OICSEs are summarized,and the challenges and perspectives on the future development of OICSEs are also highlighted for constructing superior ASSLBs.
基金National Key R&D Program of China(2022YFB3506300)Guangdong-Foshan Joint Fund(2023A1515140091)Guangdong High-level Innovation Institute Project(2021B0909050001)。
文摘All-solid-state lithium batteries(ASSLBs)are regarded as the representative of next-generation energy storage technology.It can solve the flammability hazard of liquid lithium batteries and their theoretical energy density can reach exceeding 500 Wh·kg^(-1).Silicon is one of the most attractive anode materials for high-energy ASSLBs because of its high theoretical capacity and low working potential.However,Si anode faces two key problems in practical applications.Firstly,the side reaction between Si and sulfide-based solid-state electrolytes is serious,which can form unstable interfacial phases,significantly increase interfacial impedance and deplete active lithium.Secondly,electrical/ionic contact loss caused by volume change of Si electrode during lithiation/delithiation process results in significant initial capacity loss and poor cycling stability.For this reason,a simple liquidphase approach was taken to form Li_(x)SiS_(y)layer-coated Si nanoparticles in-situ,and composite electrodes were prepared in this way.High initial coulombic efficiency(ICE)and stable cyclability for sulfide-based ASSLBs can be achieved.The results show that the Si@Li_(x)SiS_(y)-Li_(3)PS_(4)-C composite electrode exhibits a higher ICE of 77.5%at 0.13 mA·cm^(-2)compared to that of 55.9%for Si-Li_(3)PS_(4)-C electrode and a more stable cycling performance without external pressure.This indicates that the direct contact between Si and Li_(3)PS_(4)electrolyte is effectively blocked by coating with a Li_(x)SiS_(y)layer.Stable interface between Si and Li_(3)PS_(4)electrolyte can be obtained and prevent the side reactions between them.Both the stable interface and partial prelithiation of Si electrode is favorable for high initial reversibility.At the same time the presence of the coating layer reduces the mechanical stress due to the volume change of the Si particles and ensures a good stress relief.The greatly improved interfacial stability and favorable stress release ensured by the conformal coating layer can thus lead to good electrochemical performance of Si electrode in ASSLBs.
基金supported by the National Natural Science Foundation of China(No.52203261,No.52473213)the China Postdoctoral Science Foundation(2023731330)the Central Laboratory,School of Chemical and Material Engineering,Jiangnan University。
文摘Flame-retardant gel polymer electrolyte(FRGPE)with high ionic conductivity and practical safety is essential for the next generation of high energy density sodium metal batteries(SMBs).However,they suffer from serious side reactions and insufficient interfacial stability against sodium metal anode,causing severe performance degradation and even safety issues.Herein,to address these challenges,a fluoroethylene carbonate(FEC)additive confined metal-organic framework(MOF)-based composite gel(AC-MCG)interlayer was constructed upon sodium anode through a facile in-situ UV-induced photopolymerization.The FEC confined in AC-MCG induces the formation of NaF-rich inorganic solid-electrolyte interphase,effectively eliminating the side reactions between the FRGPE and sodium metal anode.Moreover,the MOF with ordered nanochannels can homogenize Na^(+)flux during the plating process and also endow the AC-MCG interlayer with high mechanical strength,thus sufficiently suppressing the growth of sodium dendrites.Benefitting from these merits of the AC-MCG interlayer,a high critical current density of 2.0 mA cm^(-2)and a long-term cycling life for over 4200 h at 0.1 mA cm^(-2)are achieved for the Na/Na symmetric cells.Besides,the solid-state SMBs paired with the constructed AC-MCG interlayer also demonstrated considerable electrochemical performance and practical safety.
基金supported by the National Natural Science Foundation of China(No.52203261,No.52473213)。
文摘Solid polymer electrolytes(SPEs)are considered one of the most promising materials for all-solid-state lithium metal batteries(ASSLMBs)due to their facile processability.However,developing SPEs with both high ionic conductivity and interfacial stability remains a challenge.Here,a donor-acceptor(D-A)like solid plasticizer,tris(pentafluorophenyl)borane(TPFPB),containing electron-rich F atoms and electrondeficient B sites,was introduced to regulate the ion transport behavior and interfacial chemistry of polyethylene oxide(PEO)-based SPEs.Owing to the multiple ion-dipole interactions(F Li^(+)TFSI^(-)and B TFSI^(-)Li^(+))between the TPFPB molecule and Li salts,a multimodal electrolyte environment featuring more free Li^(+)and trapped TFSI^(-)anions was generated,which cooperates with the reduced crystallinity of PEO,significantly facilitating the rapid migration of Li^(+).More importantly,TPFPB tends to be preferentially reduced to form a stable inorganic-rich solid electrolyte interphase on the Li-metal anode,ensuring uniform Li plating/stripping behavior.Thus,the TPFPB-modulated SPEs system achieves a high Li^(+)conductivity of 0.74 m S cm^(-1)and effectively suppresses dendrite growth,which enables a long-cycle dendrite-free Li/Li symmetric cell for over 5000 h,and remarkable electrochemical performance has been further validated in operational ASSLMBs.The findings in this work would inspire efforts to develop highperformance SPEs for all-solid-state alkali-metal batteries.
