Solid-state electrolytes(SSEs),as the core component within the next generation of key energy storage technologies-solid-state lithium batteries(SSLBs)-are significantly leading the development of future energy storag...Solid-state electrolytes(SSEs),as the core component within the next generation of key energy storage technologies-solid-state lithium batteries(SSLBs)-are significantly leading the development of future energy storage systems.Among the numerous types of SSEs,inorganic oxide garnet-structured superionic conductors Li7La3Zr2O12(LLZO)crystallized with the cubic Iaˉ3d space group have received considerable attention owing to their highly advantageous intrinsic properties encompassing reasonable lithium-ion conductivity,wide electrochemical voltage window,high shear modulus,and excellent chemical stability with electrodes.However,no SSEs possess all the properties necessary for SSLBs,thus both the ionic conductivity at room temperature and stability in ambient air regarding cubic garnet-based electrolytes are still subject to further improvement.Hence,this review comprehensively covers the nine key structural factors affecting the ion conductivity of garnet-based electrolytes comprising Li concentration,Li vacancy concentration,Li carrier concentration and mobility,Li occupancy at available sites,lattice constant,triangle bottleneck size,oxygen vacancy defects,and Li-O bonding interactions.Furthermore,the general illustration of structures and fundamental features being crucial to chemical stability is examined,including Li concentration,Li-site occupation behavior,and Li-O bonding interactions.Insights into the composition-structure-property relations among cubic garnet-based oxide ionic conductors from the perspective of their crystal structures,revealing the potential compatibility conflicts between ionic transportation and chemical stability resulting from Li-O bonding interactions.We believe that this review will lay the foundation for future reasonable structural design of oxide-based or even other types of superionic conductors,thus assisting in promoting the rapid development of alternative green and sustainable technologies.展开更多
Solid electrolytes face challenges in solid-state sodium batteries(SSSBs)because of limited ionic conductivity,increased interfacial resistance,and sodium dendrite issues.In this study,we adopted a unique Sn4+doping s...Solid electrolytes face challenges in solid-state sodium batteries(SSSBs)because of limited ionic conductivity,increased interfacial resistance,and sodium dendrite issues.In this study,we adopted a unique Sn4+doping strategy for Na_(3.2)Zr_(2)Si_(2.2)P_(0.8)O_(12)(NZSP)that caused a partial structural transition from the monoclinic(C2/c)phase to the rhombohedral(R-3c)phase in Na_(3.2)Zr_(1.9)Sn_(0.1)Si_(2.2)P_(0.8)O_(12)(NZSnSP1).X-ray diffraction(XRD)patterns and high-resolution transmission electron microscopy analyses were used to confirm this transition,where rhombohedral NZSnSP1 showed an increase in the Na2-O bond length compared with monoclinic NZSnSP1,increasing its triangular bottleneck areas and noticeably enhancing Na+ionic conductivity,a higher Na transference number,and lower electronic conductivity.NZSnSP1 also showed exceptionally high compatibility with Na metal with an increased critical current density,as evidenced by symmetric cell tests.The SSSB,fabricated using Na_(0.9)Zn_(0.22)Fe_(0.3)Mn_(0.48)O_(2)(NZFMO),Na metal,and NZSnSP1 as the cathode,anode,and the solid electrolyte and separator,respectively,maintains 65.86%of retention in the reversible capacity over 300 cycles within a voltage range of 2.0-4.0 V at 25℃ at 0.1 C.The in-situ X-ray diffraction and X-ray absorption analyses of the P and Zr K-edges confirmed that NZSnSP1 remained highly stable before and after electrochemical cycling.This crystal structure modification strategy enables the synthesis of ideal solid electrolytes for practical SSSBs.展开更多
Fiber-shaped energy storage devices(FSESDs)with exceptional flexibility for wearable power sources should be applied with solid electrolytes over liquid electrolytes due to short circuits and leakage issue during defo...Fiber-shaped energy storage devices(FSESDs)with exceptional flexibility for wearable power sources should be applied with solid electrolytes over liquid electrolytes due to short circuits and leakage issue during deformation.Among the solid options,polymer electrolytes are particularly preferred due to their robustness and flexibility,although their low ionic conductivity remains a significant challenge.Here,we present a redox polymer electrolyte(HT_RPE)with 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl(HT)as a multi-functional additive.HT acts as a plasticizer that transforms the glassy state into the rubbery state for improved chain mobility and provides distinctive ion conduction pathway by the self-exchange reaction between radical and oxidized species.These synergetic effects lead to high ionic conductivity(73.5 mS cm−1)based on a lower activation energy of 0.13 eV than other redox additives.Moreover,HT_RPE with a pseudocapacitive characteristic by HT enables an outstanding electrochemical performance of the symmetric FSESDs using carbon-based fiber electrodes(energy density of 25.4 W h kg^(−1) at a power density of 25,000 W kg^(−1))without typical active materials,along with excellent stability(capacitance retention of 91.2%after 8,000 bending cycles).This work highlights a versatile HT_RPE that utilizes the unique functionality of HT for both the high ionic conductivity and improved energy storage capability,providing a promising pathway for next-generation flexible energy storage devices.展开更多
A composite solid electrolyte comprising a Cu-Al bimetallic metal-organic framework(CAB),lithium salt(LiTFSI)and polyethylene oxide(PEO)was fabricated through molecular grafting to enhance the ionic conductivity of th...A composite solid electrolyte comprising a Cu-Al bimetallic metal-organic framework(CAB),lithium salt(LiTFSI)and polyethylene oxide(PEO)was fabricated through molecular grafting to enhance the ionic conductivity of the PEO-based electrolytes.Experimental and molecular dynamics simulation results indicated that the electrolyte with 10 wt.%CAB(PL-CAB-10%)exhibits high ionic conductivity(8.42×10~(-4)S/cm at 60℃),high Li+transference number(0.46),wide electrochemical window(4.91 V),good thermal stability,and outstanding mechanical properties.Furthermore,PL-CAB-10%exhibits excellent cycle stability in both Li-Li symmetric battery and Li/PL-CAB-10%/LiFePO4 asymmetric battery setups.These enhanced performances are primarily attributable to the introduction of the versatile CAB.The abundant metal sites in CAB can react with TFSI~-and PEO through Lewis acid-base interactions,promoting LiTFSI dissociation and improving ionic conductivity.Additionally,regular pores in CAB provide uniformly distributed sites for cation plating during cycling.展开更多
Bacterial cellulose(BC)was innovatively combined with zwitterionic copolymer acrylamide and sulfobetaine methacrylic acid ester[P(AM-co-SBMA)]to build a dual-network porous structure gel polymer electrolytes(GPEs)with...Bacterial cellulose(BC)was innovatively combined with zwitterionic copolymer acrylamide and sulfobetaine methacrylic acid ester[P(AM-co-SBMA)]to build a dual-network porous structure gel polymer electrolytes(GPEs)with high ionic conductivity.The dual network structure BC/P(AM-co-SBMA)gels were formed by a simple one-step polymerization method.The results show that ionic conductivity of BC/P(AM-co-SBMA)GPEs at the room temperature are 3.2×10^(-2) S/cm@1 M H_(2)SO_(4),4.5×10^(-2) S/cm@4 M KOH,and 3.6×10^(-2) S/cm@1 M NaCl,respectively.Using active carbon(AC)as the electrodes,BC/P(AM-co-SBMA)GPEs as both separator and electrolyte matrix,and 4 M KOH as the electrolyte,a symmetric solid supercapacitors(SSC)(AC-GPE-KOH)was assembled and testified.The specific capacitance of AC electrode is 173 F/g and remains 95.0%of the initial value after 5000 cycles and 86.2%after 10,000 cycles.展开更多
As the next generation of commercial automotive power batteries begins replacing liquid lithium batteries,many look towards all-solid-state batteries to pioneer the future.All-so lid-state batteries have attracted the...As the next generation of commercial automotive power batteries begins replacing liquid lithium batteries,many look towards all-solid-state batteries to pioneer the future.All-so lid-state batteries have attracted the attention of countless researchers around the world because of their high safety and high energy density.In recent times,halide solid-state electrolytes have become a research hotspot within solid-state electrolytes because of their potentially superior properties.In this paper,in the framework of DFT,we investigated the atomic mechanisms of improving the ionic conductivity and stability of Li_(3)YbCl_(6).Our calculations show that both trigonal and orthorhombic Li_(3)YbCl_(6) exhibit wide electrochemical windows and metastable properties(100 meV/atom>Ehull>0 meV/atom).However,the orthorhombic Li_(3)YbCl_(6) can be stabilized at high temperatures by taking the vibrational entropy into account,which is supported by the experimental results.Moreover,it is expected that because of the Yb/Li synergistic interactions that,due to their strong mutual coulomb repulsion,influence the Li^(+)transport behavior,the orthorhombic Li_(3)YbCl_(6) might have superior ionic conductivities with appropriate Li+migration paths determined by the Yb^(3+) distribution.Also,higher ionic conductivities can be obtained by regulating the random distribution of Li^(+) ions.Further Li^(+)-deficiency can also largely increase the ionic conductivity by invoking vacancies.This study helps gain a deeper understanding of the laws that govern ionic conductivities and stabilities and provides a certain theoretical reference for the experimental development and design of halide solid-state electrolytes.展开更多
We investigated the effect of additional doping with Ce on the ionic conductivity of the Nb-doped Li_(7)La_(3)Zr_(2)O_(12)(LLZO)garnet ceramics using a combination of experimental and modeling approaches.Our results i...We investigated the effect of additional doping with Ce on the ionic conductivity of the Nb-doped Li_(7)La_(3)Zr_(2)O_(12)(LLZO)garnet ceramics using a combination of experimental and modeling approaches.Our results indicate that Ce doping can alter lattice parameters of the LLZNO,leading to the enhanced lithium ionic conductivity.The Ce,Nb co-doped LLZO(LLZNCO)structure with composition Li_(6.5)La_(3)Zr_(1.5-x)Nb_(0.5)Ce_(x)O_(12)(x=0.125)exhibits a lower activation energy(E_(a)=0.39 eV)than Li_(6.5)La_(3)Zr_(1.5)Nb_(0.5)O_(12)(LLZNO)(E_(a)=0.41 eV).Furthermore,Ce doping leads to an increase in Li~+conductivity from 6.4×10^(-4)to 7×10^(-4)S/cm at room temperature.In addition,we discuss the diffusivity and conductivity of our samples using ab initio molecular dynamics simulations and propose possible mechanisms to explain the enhanced Li-ion conductivity caused by co-doping with Ce and Nb.Our results demonstrate that the LLZNCO ceramics are promising candidates for potential solid-state electrolytes for Li-ion batteries.展开更多
Ce0.8Sm0.2O1.9-δ-La0.9Sr0.1Ga0.8Mg0.2O3-δ（SDC-LSGM）is prepared by the glycine-nitrate process（GNP）.SDC-LSGM composite electrolyte samples with different weight ratios are prepared by the co-combustion method so ...Ce0.8Sm0.2O1.9-δ-La0.9Sr0.1Ga0.8Mg0.2O3-δ（SDC-LSGM）is prepared by the glycine-nitrate process（GNP）.SDC-LSGM composite electrolyte samples with different weight ratios are prepared by the co-combustion method so as to obtain homogeneous nano-sized precursor powders. The X-ray diffraction （XRD） and the scan electron microscope （SEM） are used to investigate the phases and microstructures. The measurements and analyses of oxygen ionic conductivity of SDC-LSGM are carried out through the four-terminal direct current （DC） method and the electrochemical impendence spectroscopy, respectively. The optimum weight ratio of SDC-LSGM is 8∶2, of which the ionic conductivity is 0.113 S/cm at 800℃ and the conductivity activation energy is 0.620 eV. The impendence spectra shows that the grain boundary resistance becomes the main barrier for the ionic conductivity of electrolyte at lower temperatures. The appropriate introduction of LSGM to the electrolyte SDC can not only decrease the electronic conductivity but also improve the conditions of the grain and grain boundary, which is advantageous to cause an increase in oxygen ionic conductivity.展开更多
Ionic conductivity is one of the crucial parameters for inorganic solid-state electrolytes.To explore the relationship between porosity and ionic conductivity,a series of Li_(6.4)Ga_(0.2)La_(3)Zr_(2)O_(12)garnet type ...Ionic conductivity is one of the crucial parameters for inorganic solid-state electrolytes.To explore the relationship between porosity and ionic conductivity,a series of Li_(6.4)Ga_(0.2)La_(3)Zr_(2)O_(12)garnet type solid-state electrolytes with different porosities were prepared via solid-state reaction.Based on the quantified data,an empirical decay relationship was summarized and discussed by means of mathematical model and dimensional analysis method.It suggests that open porosity causes ionic conductivity to decrease exponentially.The pre-exponential factor obeys the Arrhenius Law quite well with the activation energy of 0.23 eV,and the decay constant is averaged to be 2.62%.While the closed porosity causes ionic conductivity to decrease linearly.The slope and intercept of this linear pattern also obey the Arrhenius Law and the activation energies are 0.24 and 0.27 eV,respectively.Moreover,the total porosity is linearly dependent on the open porosity,and different sintering conditions will lead to different linear patterns with different slopes and intercepts.展开更多
As a promising solid electrolyte for thin-film lithium batteries,the amorphous Li_(0.33)La_(0.56)TiO_(3)(LLTO)thin film has gained great interest.However,enhancing ionic conductivity remains challenging in the field.H...As a promising solid electrolyte for thin-film lithium batteries,the amorphous Li_(0.33)La_(0.56)TiO_(3)(LLTO)thin film has gained great interest.However,enhancing ionic conductivity remains challenging in the field.Here,a systematical study was performed to improve the ionic conductivity of sputter-deposited LLTO thin films via the optimization of processing atmosphere and temperature.By combining the optimized oxygen partial pressure(30%),annealing temperature(300℃),and annealing atmosphere(air),an amorphous LLTO thin film with an ionic conductivity of 5.32910^(-5)·S·cm^(-1) at room temperature and activation energy of 0.26 eV was achieved.The results showed that,first,the oxygen partial pressure should be high enough to compensate for the oxygen loss,but low enough to avoid the abusive oxygen scattering effect on lithium precursors that results in a lithium-poor composition.The oxygen partial pressure needs to achieve a balance between lithium loss and oxygen defects to improve the ionic conductivity.Second,a proper annealing temperature reduces the oxygen defects of LLTO thin films while maintaining its amorphous state,which improves the ionic conductivity.Third,the highest ionic conductivity for the LLTO thin films that were annealed in air(a static space without a gas stream)occurs because of the decreased lithium loss and oxygen defects during annealing.These findings show that the lithium-ion concentration and oxygen defects affect the ionic conductivity for amorphous LLTO thin films,which provides insight into the optimization of LLTO thin-film solid electrolytes,and generates new opportunities for their application in thinfilm lithium batteries.展开更多
The Ba,Y and A1 co-doped Li_(7)La_(3)Zr_(2)O_(12)(LLZO)was prepared by the solid-state reaction method.Effect of sintering on the crystallographic structure,morphology,total conductivity,relative density and contracti...The Ba,Y and A1 co-doped Li_(7)La_(3)Zr_(2)O_(12)(LLZO)was prepared by the solid-state reaction method.Effect of sintering on the crystallographic structure,morphology,total conductivity,relative density and contractibility rate of the prepared solid electrolyte was studied,respectively.The sintered samples were characterized by X-ray diffractometer(XRD),scanning electron microscopy(SEM),electrochemical impedance spectra(EIS)and inductively coupled plasma atomic emission spectrometry(ICP-AES)techniques,respectively.The cubic garnet phase Ba,Y and Al co-doped LLZO is obtained,and the room-temperature total conductivity of the Ba,Y and Al co-doped LLZO solid electrolyte is improved significantly by eliminating the grain boundary resistances and improving the densifications with controlling sintering temperature(T)and time(t),respectively.Sintering at 1160-1190℃for 12 h and at 1190℃for6-15 h,respectively,the Ba,Y and Al co-doped LLZO solid electrolytes are cubic garnet phase.Sintering at1180-1190℃for 12 h and at 1190℃for 12-18 h,respectively,SEM images of the cross section of the Ba,Y and Al co-doped LLZO solid electrolytes exhibit the distinctively flattened morphology without any noticeable grain boundaries.The total conductivity,relative density and contractibility rate of Li_(6.52)La_(2.98)-Ba_(0.02)Zr_(1.9)Y_(0.1)Al_(0.2)O_(12)solid electrolyte are 2.96×10^(-4) S·cm^(-1),94.19%and 18.61%,respectively.展开更多
In this study, the ionic conductivity behavior in hybrid gelatin-based transparent electrolytes including various types of nanoclays with different size, shape and surface properties was characterized. The effects of ...In this study, the ionic conductivity behavior in hybrid gelatin-based transparent electrolytes including various types of nanoclays with different size, shape and surface properties was characterized. The effects of nanoclay type and nanoclay concentration as well as different experimental conditions, e.g., pH, temperature and crosslinking were also investigated. In general, the impedance spectroscopy results suggested a non- trivial role for nanoclay. Regardless of the nanoclay type, the ionic conductivity slightly increased first and then decreased by increasing the nanoclay concentration. Furthermore, among sodium montmorillonite （Na＋MMT）, lithium montmorillonite （Li＋MMT）, laponite and hydrotalcite, the hybrid electrolytes prepared by Li＋MMT showed higher ionic conductivity. The results also showed that the chemical crosslinking along with sample preparation at optimum pH, where the gelatin chains might be efficiently adsorbed on exfoliated, negatively charged clay nanosheets, plays an important role. In comparison with the ionic conductivity of the neat sample at room temperature （～10-7 S cm-1）, a ten-fold increase was observed for the crosslinked sample containing 2 wt% of Li^＋MMT prepared at optimum pH 3.5. The conductivity behavior as a function of temperature revealed the obedience with the VogeI-Fulcher-Tammann （VFT） model for all samples, suggesting the important role of segmental motions in the ionic conductivity. Finally, a qualitative explanation was presented for the mechanism of the ionic conduction in gelatin-nanoclay hybrid electrolytes.展开更多
Volume effect has been extensively investigated in several families of solid electrolytes, i.e., expanding the skeleton lattice by bigger-size substitution favors the ionic conduction. However, this effect is not appl...Volume effect has been extensively investigated in several families of solid electrolytes, i.e., expanding the skeleton lattice by bigger-size substitution favors the ionic conduction. However, this effect is not applicable in α-Li2SO4 and α-Na3PO4 based inorganic ionic plastic crystal electrolytes, a unique family of solid electrolytes. Here, it is proposed that the underlying rotational motion effect of polyanion, which is actually inhibited by the substitution of bigger-size polyanion in single-phase solid solution region and causes the unexpected lowering of the ionic conductivity instead, should need the more consideration. Furthermore, through utilizing the rotational motion effect of polyanion, it is given that a new explanation of the ionic conductivities of Li10MP2S12 （M = Si, Ge, Se） electrolytes deviating from the volume effect. These results inspire new vision of rationalization of the high-performance solid electrolytes by tuning the rotational motion effect of polyanion.展开更多
Solid polymer electrolytes(SPEs)have emerged as one of the most promising candidates for building solid-state lithium batteries due to their excellent flexibility,scalability,and interfacial compatibility with electro...Solid polymer electrolytes(SPEs)have emerged as one of the most promising candidates for building solid-state lithium batteries due to their excellent flexibility,scalability,and interfacial compatibility with electrodes.However,the low ionic conductivity and poor cyclic stability of SPEs do not meet the requirements for practical applications of lithium batteries.Here,a novel polymer dispersed ionic liquid-based solid polymer electrolyte(PDIL-SPE)is fabricated using the in situ polymerization-induced phase separation(PIPS)method.The as-prepared PDIL-SPE possesses both outstanding ionic conductivity(0.74 mS cm^(-1) at 25℃)and a wide electrochemical window(up to 4.86 V),and the formed unique three-dimensional(3D)co-continuous structure of polymer matrix and ionic liquid in PDIL-SPE can promote the transport of lithium ions.Also,the 3D co-continuous structure of PDIL-SPE effectively accommodates the severe volume expansion for prolonged lithium plating and stripping processes over 1000 h at 0.5 mA cm^(-2) under 25℃.Moreover,the LiFePO_(4)//Li coin cell can work stably over 150 cycles at a 1 C rate under room temperature with a capacity retention of 90.6%from 111.1 to 100.7 mAh g^(-1).The PDIL-SPE composite is a promising material system for enabling the ultrastable operation of solid-state lithium-metal batteries.展开更多
The conventional liquid electrolytes(LEs) have a high level of ionic conductivity;however, they often suffer from the poor processability and safety risks of potential leakage. Although solid-state electrolytes(SSEs) ...The conventional liquid electrolytes(LEs) have a high level of ionic conductivity;however, they often suffer from the poor processability and safety risks of potential leakage. Although solid-state electrolytes(SSEs) can solve these inherent problems of LEs, the ionic conductivity of most SSEs is several magnitudes lower than these of LEs. Herein, we report a novel strategy by building liquid ion-transport channels in a solid framework and prepared an electrolyte-locked separator(ELS) using a collagen fiber membrane(CFm). The liquid electrolyte was primarily infiltrated in the smaller voids of CFm, and its ionic conductivity could attain to 9.0×10-3 S cm-1 when the electrolyte absorption(EA) reached up to 112.0%. After centrifuging treatment, the electrolyte retentions(ER) and ionic conductivities of ELS were 108.93% and 8.37×10-3 S cm-1, respectively, which were much higher than those of commercial cellulose separator(CS), exerting excellent liquid-locking performances. In particular, the electrical double-layer capacitors(EDLC) assembled by ELS or CS were characterized and exhibited similar electrochemical performance,demonstrating the satisfactory ability and applicability of ELS for commercial use. In addition, the ELSbased EDLC exhibited favorable flexibility with relative lower loss of capacitance under different angles of bending.展开更多
Solid electrolyte(SE)is the most crucial factor to fabricate safe and high-performance all-solid-state lithium-ion batteries.However,the most commonly reported SE,including solid polymer electrolyte(SPE)and inorganic ...Solid electrolyte(SE)is the most crucial factor to fabricate safe and high-performance all-solid-state lithium-ion batteries.However,the most commonly reported SE,including solid polymer electrolyte(SPE)and inorganic oxides and sulfides,suffer problems of low ionic conductivity at room temperature for SPE and large interfacial impedance with electrodes for inorganic electrolytes.Here we for the first time demonstrate a novel ionic plastic crystal lithium salt solid electrolyte(OLiSSE)fast ion-conductor dilithium(1,3-diethyl-4,5-dicarboxylate)imidazole bromide with ordered Li-ion conductive nanopathways and an exceptional ionic conductivity of 4.4×10^(−3)Scm^(−1)at 30℃.The prepared OLiSSE exhibits apparent characters of typical ionic plastic crystals in the temperature range of−20 to 70℃,and shows remarkable thermal stability and electrochemical stability below 150℃ and 4.7 V,respectively.No lithium dendrite or short circuit behavior is detected for the Li|OLiSSE|Li cell after the galvanostatic charge-discharge test for 500 h.The fabricated Li|OLiSSE|LiFePO_(4) all-solid-state cell without using any separator and liquid plasticizer directly delivers an initial discharge capacity of 151.4 mAh g^(−1) at the discharge rate of 0.1 C,and shows excellent charge-discharge cycle stability,implying large potential application in the next generation of safe and flexible all-solid-state lithium batteries.展开更多
This work studies the ionic conductivity of nanosized Gd-, Sm-, and Y-doped ceria prepared by the infiltration/impregnation method. The nanoparticles were deposited onto porous pure ceria substrates via infiltration- ...This work studies the ionic conductivity of nanosized Gd-, Sm-, and Y-doped ceria prepared by the infiltration/impregnation method. The nanoparticles were deposited onto porous pure ceria substrates via infiltration- heating processes, and the conductivity was determined with the electrochemical impedance spectroscopy （EIS） using the conductive model for infiltrated phases. The conductivity of the infiltrated doped ceria changes with the doping amount, and Gd0.25Ce0.75O2-δ, Sm0.2Ce0.8O2-δ, and Y0.15Ce0.85O2-δ show the highest values of 2.56, 3.01, and 2.07 × 10-3 S.cm-1 at 600 ℃, respectively. Overall, Sin-doped samples show the highest conductivity, whileY-doped samples show the lowest conductivity. In con- sideration of the Bruggeman factor, the intrinsic conduc- tivity of the infiltrated doped ceria was calculated. Compared with the bulk doped ceria, the intrinsic con- ductivity is higher while the activation energy is lower, which may suggest different conduction mechanisms. Besides, co-doping effects on the conductivity of the infiltrated sample are less obvious than those of the bulk sample.展开更多
Lithium metal batteries assembled with solid-state electrolyte can offer high safety and volumetric energy density compared to liquid electrolyte.The polymer solid-state electrolytes of poly(ethylene oxide)(PEO)are wi...Lithium metal batteries assembled with solid-state electrolyte can offer high safety and volumetric energy density compared to liquid electrolyte.The polymer solid-state electrolytes of poly(ethylene oxide)(PEO)are widely used in lithium metal solid-state batteries due to their unique properties.However,there are still some defects such as low ionic conductivity at room temperature and weak inhibition of lithium dendrite growth.Herein,the spiny inorganic nanofibers heterostructure with mullite whiskers grown on the surface of aluminum fluoride(AlF_(3))nanofibers are introduced into the PEOLi TFSI electrolytes for the first time to prepare composite solid-state electrolytes.The AlF_(3)as a strong Lewis acid can adsorb anions and promote the dissociation of Li salts.Besides,the specially threedimensional(3D)structure enlarges the effective contacting interface with the PEO polymer,which allows the lithium ions to be transported not only along the large aspect ratio of AlF3nanofibers,but also along the mullite phase in the transmembrane direction rapidly.Thereby,the transport channel of lithium ions at the spiny inorganic nanofibers-polymer interface is further improved.Benefiting from these advantages,the obtained composite solid-state electrolyte has a high ionic conductivity of 1.58×10^(-4)S cm^(-1)at 30℃and the lithium ions transfer number of 0.53.In addition,the AlF3has strong binding energy with anions,low electronic conductivity and wide electrochemical stability window,and reduced nucleation overpotential of lithium during cycling,which is positive for lithium dendrite suppression in solid-state electrolytes.Thus,the assembled symmetric Li/Li symmetric batteries exhibit stable cycling performance at different area capacities of 0.15,0.2,0.3 and 0.4 m A h cm^(-2).More importantly,the LiFePO_(4)(LFP)/Li battery still has 113.5 m A h g-1remaining after 400 cycles at 50℃and the Coulomb efficiency is nearly 100%during the long cycle.Overall,the interconnected structure of 3D spiny inorganic heterostructure nanofiber constitutes fast and uninterrupted lithium ions transport channels,maximizing the synergistic effect of interfacial transport of inorganic fillers and reducing PEO crystallinity,thus providing a novel approach to high performance solid-state electrolytes.展开更多
The valence electron structures of Sr- and Mg-doped LaGaO3 ceramics with different compositions were calculated by Empirical Electron Theory of Solids and Molecules （EET）. A criterion for the ionic conductivity was ...The valence electron structures of Sr- and Mg-doped LaGaO3 ceramics with different compositions were calculated by Empirical Electron Theory of Solids and Molecules （EET）. A criterion for the ionic conductivity was proposed, i.e. the 1/（nAnB） increases with increasing the ionic conductivity when x or y〈20% （in molar fraction）.展开更多
The ionic conductivity and the mechanical strength are two key factors for the performance of poly（ethylene oxide）（PEO） based polyelectrolytes. However, crystallized PEO suppresses ion conductivity at low temperat...The ionic conductivity and the mechanical strength are two key factors for the performance of poly（ethylene oxide）（PEO） based polyelectrolytes. However, crystallized PEO suppresses ion conductivity at low temperature and melted PEO has low mechanical strength at high temperature. Here, random binary brush copolymer composed of PEO-and polystyrene（PS）-based side chains is synthesized. PEO crystallinity is suppressed by the introduction of PS brushes. Doping with lithium trifluoromethanesulfonate（Li Tf） induces microphase separation. Due to a random arrangement of the brushes, the microphase segregation is incomplete even at high salt loading, which provides both high ionic conductivity and high mechanical strength at room temperature. These results provide opportunities for the design of polymeric electrolytes to be used at room temperature.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22171102 and 22090044)the National Key R&D Program of China(Nos.2021YFF0500502 and 2023YFA1506304)+2 种基金the Jilin Province Science and Technology Development Plan(No.20230101024JC)the"Medicine+X"crossinnovation team of Bethune Medical Department of Jilin University"Leading the Charge with Open Competition"construction project(No.2022JBGS04)the Jilin University Graduate Training Office(Nos.2021JGZ08 and 2022YJSJIP20).
文摘Solid-state electrolytes(SSEs),as the core component within the next generation of key energy storage technologies-solid-state lithium batteries(SSLBs)-are significantly leading the development of future energy storage systems.Among the numerous types of SSEs,inorganic oxide garnet-structured superionic conductors Li7La3Zr2O12(LLZO)crystallized with the cubic Iaˉ3d space group have received considerable attention owing to their highly advantageous intrinsic properties encompassing reasonable lithium-ion conductivity,wide electrochemical voltage window,high shear modulus,and excellent chemical stability with electrodes.However,no SSEs possess all the properties necessary for SSLBs,thus both the ionic conductivity at room temperature and stability in ambient air regarding cubic garnet-based electrolytes are still subject to further improvement.Hence,this review comprehensively covers the nine key structural factors affecting the ion conductivity of garnet-based electrolytes comprising Li concentration,Li vacancy concentration,Li carrier concentration and mobility,Li occupancy at available sites,lattice constant,triangle bottleneck size,oxygen vacancy defects,and Li-O bonding interactions.Furthermore,the general illustration of structures and fundamental features being crucial to chemical stability is examined,including Li concentration,Li-site occupation behavior,and Li-O bonding interactions.Insights into the composition-structure-property relations among cubic garnet-based oxide ionic conductors from the perspective of their crystal structures,revealing the potential compatibility conflicts between ionic transportation and chemical stability resulting from Li-O bonding interactions.We believe that this review will lay the foundation for future reasonable structural design of oxide-based or even other types of superionic conductors,thus assisting in promoting the rapid development of alternative green and sustainable technologies.
基金supported by the National Research Foundation of Korea(RS-2024-00404414)the National Research Council of Science&Technology(NST,No.GTL24011-000)funded by the Ministry of Science and ICTsupported by the KIST Institutional Program(Project No.2E33270).
文摘Solid electrolytes face challenges in solid-state sodium batteries(SSSBs)because of limited ionic conductivity,increased interfacial resistance,and sodium dendrite issues.In this study,we adopted a unique Sn4+doping strategy for Na_(3.2)Zr_(2)Si_(2.2)P_(0.8)O_(12)(NZSP)that caused a partial structural transition from the monoclinic(C2/c)phase to the rhombohedral(R-3c)phase in Na_(3.2)Zr_(1.9)Sn_(0.1)Si_(2.2)P_(0.8)O_(12)(NZSnSP1).X-ray diffraction(XRD)patterns and high-resolution transmission electron microscopy analyses were used to confirm this transition,where rhombohedral NZSnSP1 showed an increase in the Na2-O bond length compared with monoclinic NZSnSP1,increasing its triangular bottleneck areas and noticeably enhancing Na+ionic conductivity,a higher Na transference number,and lower electronic conductivity.NZSnSP1 also showed exceptionally high compatibility with Na metal with an increased critical current density,as evidenced by symmetric cell tests.The SSSB,fabricated using Na_(0.9)Zn_(0.22)Fe_(0.3)Mn_(0.48)O_(2)(NZFMO),Na metal,and NZSnSP1 as the cathode,anode,and the solid electrolyte and separator,respectively,maintains 65.86%of retention in the reversible capacity over 300 cycles within a voltage range of 2.0-4.0 V at 25℃ at 0.1 C.The in-situ X-ray diffraction and X-ray absorption analyses of the P and Zr K-edges confirmed that NZSnSP1 remained highly stable before and after electrochemical cycling.This crystal structure modification strategy enables the synthesis of ideal solid electrolytes for practical SSSBs.
基金supported by Korea Institute of Science and Technology(KIST)Institutional Program and Open Research Program(ORP)This work was also supported by grant from the National Research Foundation(NRF)of Korea government(RS-2024-00433159 and RS-2023-00208313)from ITECH R&D program of MOTIE/KEIT(RS-2023-00257573).
文摘Fiber-shaped energy storage devices(FSESDs)with exceptional flexibility for wearable power sources should be applied with solid electrolytes over liquid electrolytes due to short circuits and leakage issue during deformation.Among the solid options,polymer electrolytes are particularly preferred due to their robustness and flexibility,although their low ionic conductivity remains a significant challenge.Here,we present a redox polymer electrolyte(HT_RPE)with 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl(HT)as a multi-functional additive.HT acts as a plasticizer that transforms the glassy state into the rubbery state for improved chain mobility and provides distinctive ion conduction pathway by the self-exchange reaction between radical and oxidized species.These synergetic effects lead to high ionic conductivity(73.5 mS cm−1)based on a lower activation energy of 0.13 eV than other redox additives.Moreover,HT_RPE with a pseudocapacitive characteristic by HT enables an outstanding electrochemical performance of the symmetric FSESDs using carbon-based fiber electrodes(energy density of 25.4 W h kg^(−1) at a power density of 25,000 W kg^(−1))without typical active materials,along with excellent stability(capacitance retention of 91.2%after 8,000 bending cycles).This work highlights a versatile HT_RPE that utilizes the unique functionality of HT for both the high ionic conductivity and improved energy storage capability,providing a promising pathway for next-generation flexible energy storage devices.
基金supported by the National Natural Science Foundation of China(No.21501015)the Hunan Provincial Natural Science Foundation,China(No.2022JJ30604)Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation,China(No.2022CL01)。
文摘A composite solid electrolyte comprising a Cu-Al bimetallic metal-organic framework(CAB),lithium salt(LiTFSI)and polyethylene oxide(PEO)was fabricated through molecular grafting to enhance the ionic conductivity of the PEO-based electrolytes.Experimental and molecular dynamics simulation results indicated that the electrolyte with 10 wt.%CAB(PL-CAB-10%)exhibits high ionic conductivity(8.42×10~(-4)S/cm at 60℃),high Li+transference number(0.46),wide electrochemical window(4.91 V),good thermal stability,and outstanding mechanical properties.Furthermore,PL-CAB-10%exhibits excellent cycle stability in both Li-Li symmetric battery and Li/PL-CAB-10%/LiFePO4 asymmetric battery setups.These enhanced performances are primarily attributable to the introduction of the versatile CAB.The abundant metal sites in CAB can react with TFSI~-and PEO through Lewis acid-base interactions,promoting LiTFSI dissociation and improving ionic conductivity.Additionally,regular pores in CAB provide uniformly distributed sites for cation plating during cycling.
基金Funded by National Natural Science Foundation of China(No.51472166)。
文摘Bacterial cellulose(BC)was innovatively combined with zwitterionic copolymer acrylamide and sulfobetaine methacrylic acid ester[P(AM-co-SBMA)]to build a dual-network porous structure gel polymer electrolytes(GPEs)with high ionic conductivity.The dual network structure BC/P(AM-co-SBMA)gels were formed by a simple one-step polymerization method.The results show that ionic conductivity of BC/P(AM-co-SBMA)GPEs at the room temperature are 3.2×10^(-2) S/cm@1 M H_(2)SO_(4),4.5×10^(-2) S/cm@4 M KOH,and 3.6×10^(-2) S/cm@1 M NaCl,respectively.Using active carbon(AC)as the electrodes,BC/P(AM-co-SBMA)GPEs as both separator and electrolyte matrix,and 4 M KOH as the electrolyte,a symmetric solid supercapacitors(SSC)(AC-GPE-KOH)was assembled and testified.The specific capacitance of AC electrode is 173 F/g and remains 95.0%of the initial value after 5000 cycles and 86.2%after 10,000 cycles.
基金Project supported by the GRINM Innovation Fund Project(2020TS0301)Jilin Province Science and Technology Major Project(20210301021GX)National Natural Science Foundation of China(U21A2080)。
文摘As the next generation of commercial automotive power batteries begins replacing liquid lithium batteries,many look towards all-solid-state batteries to pioneer the future.All-so lid-state batteries have attracted the attention of countless researchers around the world because of their high safety and high energy density.In recent times,halide solid-state electrolytes have become a research hotspot within solid-state electrolytes because of their potentially superior properties.In this paper,in the framework of DFT,we investigated the atomic mechanisms of improving the ionic conductivity and stability of Li_(3)YbCl_(6).Our calculations show that both trigonal and orthorhombic Li_(3)YbCl_(6) exhibit wide electrochemical windows and metastable properties(100 meV/atom>Ehull>0 meV/atom).However,the orthorhombic Li_(3)YbCl_(6) can be stabilized at high temperatures by taking the vibrational entropy into account,which is supported by the experimental results.Moreover,it is expected that because of the Yb/Li synergistic interactions that,due to their strong mutual coulomb repulsion,influence the Li^(+)transport behavior,the orthorhombic Li_(3)YbCl_(6) might have superior ionic conductivities with appropriate Li+migration paths determined by the Yb^(3+) distribution.Also,higher ionic conductivities can be obtained by regulating the random distribution of Li^(+) ions.Further Li^(+)-deficiency can also largely increase the ionic conductivity by invoking vacancies.This study helps gain a deeper understanding of the laws that govern ionic conductivities and stabilities and provides a certain theoretical reference for the experimental development and design of halide solid-state electrolytes.
基金Project supported by the Scientific Research Startup Fund of Inner Mongolia University of Science and Technology(0303052202)Natural Science Foundation of Inner Mongolia Autonomous Region(2020ZD17,2022FX08)。
文摘We investigated the effect of additional doping with Ce on the ionic conductivity of the Nb-doped Li_(7)La_(3)Zr_(2)O_(12)(LLZO)garnet ceramics using a combination of experimental and modeling approaches.Our results indicate that Ce doping can alter lattice parameters of the LLZNO,leading to the enhanced lithium ionic conductivity.The Ce,Nb co-doped LLZO(LLZNCO)structure with composition Li_(6.5)La_(3)Zr_(1.5-x)Nb_(0.5)Ce_(x)O_(12)(x=0.125)exhibits a lower activation energy(E_(a)=0.39 eV)than Li_(6.5)La_(3)Zr_(1.5)Nb_(0.5)O_(12)(LLZNO)(E_(a)=0.41 eV).Furthermore,Ce doping leads to an increase in Li~+conductivity from 6.4×10^(-4)to 7×10^(-4)S/cm at room temperature.In addition,we discuss the diffusivity and conductivity of our samples using ab initio molecular dynamics simulations and propose possible mechanisms to explain the enhanced Li-ion conductivity caused by co-doping with Ce and Nb.Our results demonstrate that the LLZNCO ceramics are promising candidates for potential solid-state electrolytes for Li-ion batteries.
基金The National Basic Research Program of China (973 Program) (No.2007CB936300)the Natural Science Foundation of Jiangsu Province (No.BK2009293)
文摘Ce0.8Sm0.2O1.9-δ-La0.9Sr0.1Ga0.8Mg0.2O3-δ（SDC-LSGM）is prepared by the glycine-nitrate process（GNP）.SDC-LSGM composite electrolyte samples with different weight ratios are prepared by the co-combustion method so as to obtain homogeneous nano-sized precursor powders. The X-ray diffraction （XRD） and the scan electron microscope （SEM） are used to investigate the phases and microstructures. The measurements and analyses of oxygen ionic conductivity of SDC-LSGM are carried out through the four-terminal direct current （DC） method and the electrochemical impendence spectroscopy, respectively. The optimum weight ratio of SDC-LSGM is 8∶2, of which the ionic conductivity is 0.113 S/cm at 800℃ and the conductivity activation energy is 0.620 eV. The impendence spectra shows that the grain boundary resistance becomes the main barrier for the ionic conductivity of electrolyte at lower temperatures. The appropriate introduction of LSGM to the electrolyte SDC can not only decrease the electronic conductivity but also improve the conditions of the grain and grain boundary, which is advantageous to cause an increase in oxygen ionic conductivity.
基金supported by the Innovation and Entrepreneurship Project of Hunan Province,China(No.2019GK5053)Program of Huxiang Young Talents,China(No.2019RS2002)+1 种基金the Natural Science Foundation for Distinguished Young Scholars of Hunan Province,China(No.2020JJ2047)the Fundamental Research Funds for the Central Universities of Central South University,China。
文摘Ionic conductivity is one of the crucial parameters for inorganic solid-state electrolytes.To explore the relationship between porosity and ionic conductivity,a series of Li_(6.4)Ga_(0.2)La_(3)Zr_(2)O_(12)garnet type solid-state electrolytes with different porosities were prepared via solid-state reaction.Based on the quantified data,an empirical decay relationship was summarized and discussed by means of mathematical model and dimensional analysis method.It suggests that open porosity causes ionic conductivity to decrease exponentially.The pre-exponential factor obeys the Arrhenius Law quite well with the activation energy of 0.23 eV,and the decay constant is averaged to be 2.62%.While the closed porosity causes ionic conductivity to decrease linearly.The slope and intercept of this linear pattern also obey the Arrhenius Law and the activation energies are 0.24 and 0.27 eV,respectively.Moreover,the total porosity is linearly dependent on the open porosity,and different sintering conditions will lead to different linear patterns with different slopes and intercepts.
基金This study was financially supported by the National Natural Science Funds of China(No.21905040)the Startup Funds from the University of Electronic Science and Technology of China,the National Key Research and Development Program of China(Nos.2017YFB0702802 and 2018YFB0905400)Shanghai Venus Project(No.18QB1402600).
文摘As a promising solid electrolyte for thin-film lithium batteries,the amorphous Li_(0.33)La_(0.56)TiO_(3)(LLTO)thin film has gained great interest.However,enhancing ionic conductivity remains challenging in the field.Here,a systematical study was performed to improve the ionic conductivity of sputter-deposited LLTO thin films via the optimization of processing atmosphere and temperature.By combining the optimized oxygen partial pressure(30%),annealing temperature(300℃),and annealing atmosphere(air),an amorphous LLTO thin film with an ionic conductivity of 5.32910^(-5)·S·cm^(-1) at room temperature and activation energy of 0.26 eV was achieved.The results showed that,first,the oxygen partial pressure should be high enough to compensate for the oxygen loss,but low enough to avoid the abusive oxygen scattering effect on lithium precursors that results in a lithium-poor composition.The oxygen partial pressure needs to achieve a balance between lithium loss and oxygen defects to improve the ionic conductivity.Second,a proper annealing temperature reduces the oxygen defects of LLTO thin films while maintaining its amorphous state,which improves the ionic conductivity.Third,the highest ionic conductivity for the LLTO thin films that were annealed in air(a static space without a gas stream)occurs because of the decreased lithium loss and oxygen defects during annealing.These findings show that the lithium-ion concentration and oxygen defects affect the ionic conductivity for amorphous LLTO thin films,which provides insight into the optimization of LLTO thin-film solid electrolytes,and generates new opportunities for their application in thinfilm lithium batteries.
基金financially supported by the National Natural Science Foundation of China(Nos.51572176 and 51372153)the Plateau Discipline Construction Program from Shanghai Municipal Education Commission(No.0817)the Collaborative Innovation Fund of Shanghai Institute of Technology(No.XTCX2017-5)。
文摘The Ba,Y and A1 co-doped Li_(7)La_(3)Zr_(2)O_(12)(LLZO)was prepared by the solid-state reaction method.Effect of sintering on the crystallographic structure,morphology,total conductivity,relative density and contractibility rate of the prepared solid electrolyte was studied,respectively.The sintered samples were characterized by X-ray diffractometer(XRD),scanning electron microscopy(SEM),electrochemical impedance spectra(EIS)and inductively coupled plasma atomic emission spectrometry(ICP-AES)techniques,respectively.The cubic garnet phase Ba,Y and Al co-doped LLZO is obtained,and the room-temperature total conductivity of the Ba,Y and Al co-doped LLZO solid electrolyte is improved significantly by eliminating the grain boundary resistances and improving the densifications with controlling sintering temperature(T)and time(t),respectively.Sintering at 1160-1190℃for 12 h and at 1190℃for6-15 h,respectively,the Ba,Y and Al co-doped LLZO solid electrolytes are cubic garnet phase.Sintering at1180-1190℃for 12 h and at 1190℃for 12-18 h,respectively,SEM images of the cross section of the Ba,Y and Al co-doped LLZO solid electrolytes exhibit the distinctively flattened morphology without any noticeable grain boundaries.The total conductivity,relative density and contractibility rate of Li_(6.52)La_(2.98)-Ba_(0.02)Zr_(1.9)Y_(0.1)Al_(0.2)O_(12)solid electrolyte are 2.96×10^(-4) S·cm^(-1),94.19%and 18.61%,respectively.
基金supports from the Iranian Nanotechnology Initiative 41118/1390.03.31the vice-president for Research and Technology of the University of Tehran are gratefully appreciated
文摘In this study, the ionic conductivity behavior in hybrid gelatin-based transparent electrolytes including various types of nanoclays with different size, shape and surface properties was characterized. The effects of nanoclay type and nanoclay concentration as well as different experimental conditions, e.g., pH, temperature and crosslinking were also investigated. In general, the impedance spectroscopy results suggested a non- trivial role for nanoclay. Regardless of the nanoclay type, the ionic conductivity slightly increased first and then decreased by increasing the nanoclay concentration. Furthermore, among sodium montmorillonite （Na＋MMT）, lithium montmorillonite （Li＋MMT）, laponite and hydrotalcite, the hybrid electrolytes prepared by Li＋MMT showed higher ionic conductivity. The results also showed that the chemical crosslinking along with sample preparation at optimum pH, where the gelatin chains might be efficiently adsorbed on exfoliated, negatively charged clay nanosheets, plays an important role. In comparison with the ionic conductivity of the neat sample at room temperature （～10-7 S cm-1）, a ten-fold increase was observed for the crosslinked sample containing 2 wt% of Li^＋MMT prepared at optimum pH 3.5. The conductivity behavior as a function of temperature revealed the obedience with the VogeI-Fulcher-Tammann （VFT） model for all samples, suggesting the important role of segmental motions in the ionic conductivity. Finally, a qualitative explanation was presented for the mechanism of the ionic conduction in gelatin-nanoclay hybrid electrolytes.
基金financially supported by the National Natural Science Foundation of China(Nos.U1430104,51622207 and 51372228)the National Key Research and Development Program of China(No.2017YFB0701600)
文摘Volume effect has been extensively investigated in several families of solid electrolytes, i.e., expanding the skeleton lattice by bigger-size substitution favors the ionic conduction. However, this effect is not applicable in α-Li2SO4 and α-Na3PO4 based inorganic ionic plastic crystal electrolytes, a unique family of solid electrolytes. Here, it is proposed that the underlying rotational motion effect of polyanion, which is actually inhibited by the substitution of bigger-size polyanion in single-phase solid solution region and causes the unexpected lowering of the ionic conductivity instead, should need the more consideration. Furthermore, through utilizing the rotational motion effect of polyanion, it is given that a new explanation of the ionic conductivities of Li10MP2S12 （M = Si, Ge, Se） electrolytes deviating from the volume effect. These results inspire new vision of rationalization of the high-performance solid electrolytes by tuning the rotational motion effect of polyanion.
基金supported by the National Key R&D Program of China (2020YFE0100200)the National Natural Science Foundation of China (Grant Nos.51921002,51927806).
文摘Solid polymer electrolytes(SPEs)have emerged as one of the most promising candidates for building solid-state lithium batteries due to their excellent flexibility,scalability,and interfacial compatibility with electrodes.However,the low ionic conductivity and poor cyclic stability of SPEs do not meet the requirements for practical applications of lithium batteries.Here,a novel polymer dispersed ionic liquid-based solid polymer electrolyte(PDIL-SPE)is fabricated using the in situ polymerization-induced phase separation(PIPS)method.The as-prepared PDIL-SPE possesses both outstanding ionic conductivity(0.74 mS cm^(-1) at 25℃)and a wide electrochemical window(up to 4.86 V),and the formed unique three-dimensional(3D)co-continuous structure of polymer matrix and ionic liquid in PDIL-SPE can promote the transport of lithium ions.Also,the 3D co-continuous structure of PDIL-SPE effectively accommodates the severe volume expansion for prolonged lithium plating and stripping processes over 1000 h at 0.5 mA cm^(-2) under 25℃.Moreover,the LiFePO_(4)//Li coin cell can work stably over 150 cycles at a 1 C rate under room temperature with a capacity retention of 90.6%from 111.1 to 100.7 mAh g^(-1).The PDIL-SPE composite is a promising material system for enabling the ultrastable operation of solid-state lithium-metal batteries.
基金supported by the National Natural Science Foundation of China (21878191)。
文摘The conventional liquid electrolytes(LEs) have a high level of ionic conductivity;however, they often suffer from the poor processability and safety risks of potential leakage. Although solid-state electrolytes(SSEs) can solve these inherent problems of LEs, the ionic conductivity of most SSEs is several magnitudes lower than these of LEs. Herein, we report a novel strategy by building liquid ion-transport channels in a solid framework and prepared an electrolyte-locked separator(ELS) using a collagen fiber membrane(CFm). The liquid electrolyte was primarily infiltrated in the smaller voids of CFm, and its ionic conductivity could attain to 9.0×10-3 S cm-1 when the electrolyte absorption(EA) reached up to 112.0%. After centrifuging treatment, the electrolyte retentions(ER) and ionic conductivities of ELS were 108.93% and 8.37×10-3 S cm-1, respectively, which were much higher than those of commercial cellulose separator(CS), exerting excellent liquid-locking performances. In particular, the electrical double-layer capacitors(EDLC) assembled by ELS or CS were characterized and exhibited similar electrochemical performance,demonstrating the satisfactory ability and applicability of ELS for commercial use. In addition, the ELSbased EDLC exhibited favorable flexibility with relative lower loss of capacitance under different angles of bending.
基金the financial support of the National Natural Science Foundation of China(21961044,22160901)the Yunnan University’s Research Innovation Fund for graduate students(2020220)。
文摘Solid electrolyte(SE)is the most crucial factor to fabricate safe and high-performance all-solid-state lithium-ion batteries.However,the most commonly reported SE,including solid polymer electrolyte(SPE)and inorganic oxides and sulfides,suffer problems of low ionic conductivity at room temperature for SPE and large interfacial impedance with electrodes for inorganic electrolytes.Here we for the first time demonstrate a novel ionic plastic crystal lithium salt solid electrolyte(OLiSSE)fast ion-conductor dilithium(1,3-diethyl-4,5-dicarboxylate)imidazole bromide with ordered Li-ion conductive nanopathways and an exceptional ionic conductivity of 4.4×10^(−3)Scm^(−1)at 30℃.The prepared OLiSSE exhibits apparent characters of typical ionic plastic crystals in the temperature range of−20 to 70℃,and shows remarkable thermal stability and electrochemical stability below 150℃ and 4.7 V,respectively.No lithium dendrite or short circuit behavior is detected for the Li|OLiSSE|Li cell after the galvanostatic charge-discharge test for 500 h.The fabricated Li|OLiSSE|LiFePO_(4) all-solid-state cell without using any separator and liquid plasticizer directly delivers an initial discharge capacity of 151.4 mAh g^(−1) at the discharge rate of 0.1 C,and shows excellent charge-discharge cycle stability,implying large potential application in the next generation of safe and flexible all-solid-state lithium batteries.
基金financially supported by the China Postdoctoral Science Foundation-Chinese Academy of Sciences(CPSF-CAS)Joint Foundation for Excellent Postdoctoral Fellowsthe National Natural Science Foundation for Distinguished Young Scholars of China (No.51625204)the National Nature Science Foundation of China (91645101)
文摘This work studies the ionic conductivity of nanosized Gd-, Sm-, and Y-doped ceria prepared by the infiltration/impregnation method. The nanoparticles were deposited onto porous pure ceria substrates via infiltration- heating processes, and the conductivity was determined with the electrochemical impedance spectroscopy （EIS） using the conductive model for infiltrated phases. The conductivity of the infiltrated doped ceria changes with the doping amount, and Gd0.25Ce0.75O2-δ, Sm0.2Ce0.8O2-δ, and Y0.15Ce0.85O2-δ show the highest values of 2.56, 3.01, and 2.07 × 10-3 S.cm-1 at 600 ℃, respectively. Overall, Sin-doped samples show the highest conductivity, whileY-doped samples show the lowest conductivity. In con- sideration of the Bruggeman factor, the intrinsic conduc- tivity of the infiltrated doped ceria was calculated. Compared with the bulk doped ceria, the intrinsic con- ductivity is higher while the activation energy is lower, which may suggest different conduction mechanisms. Besides, co-doping effects on the conductivity of the infiltrated sample are less obvious than those of the bulk sample.
基金supported by the National Natural Science Foundation of China(51973157,61904123,52103061,52203066)the Science&Technology Development Fund of Tianjin Education Commission for Higher Education(2018KJ196)+3 种基金the project funded by China Postdoctoral Science Foundation(2021T140419)Tianjin Municipal College Student’Innovation and Entrepreneurship Training Program(202110058052)the National Innovation and Entrepreneurship Training Program for College Students(202110058017)the State Key Laboratory of Membrane and Membrane Separation,Tiangong University。
文摘Lithium metal batteries assembled with solid-state electrolyte can offer high safety and volumetric energy density compared to liquid electrolyte.The polymer solid-state electrolytes of poly(ethylene oxide)(PEO)are widely used in lithium metal solid-state batteries due to their unique properties.However,there are still some defects such as low ionic conductivity at room temperature and weak inhibition of lithium dendrite growth.Herein,the spiny inorganic nanofibers heterostructure with mullite whiskers grown on the surface of aluminum fluoride(AlF_(3))nanofibers are introduced into the PEOLi TFSI electrolytes for the first time to prepare composite solid-state electrolytes.The AlF_(3)as a strong Lewis acid can adsorb anions and promote the dissociation of Li salts.Besides,the specially threedimensional(3D)structure enlarges the effective contacting interface with the PEO polymer,which allows the lithium ions to be transported not only along the large aspect ratio of AlF3nanofibers,but also along the mullite phase in the transmembrane direction rapidly.Thereby,the transport channel of lithium ions at the spiny inorganic nanofibers-polymer interface is further improved.Benefiting from these advantages,the obtained composite solid-state electrolyte has a high ionic conductivity of 1.58×10^(-4)S cm^(-1)at 30℃and the lithium ions transfer number of 0.53.In addition,the AlF3has strong binding energy with anions,low electronic conductivity and wide electrochemical stability window,and reduced nucleation overpotential of lithium during cycling,which is positive for lithium dendrite suppression in solid-state electrolytes.Thus,the assembled symmetric Li/Li symmetric batteries exhibit stable cycling performance at different area capacities of 0.15,0.2,0.3 and 0.4 m A h cm^(-2).More importantly,the LiFePO_(4)(LFP)/Li battery still has 113.5 m A h g-1remaining after 400 cycles at 50℃and the Coulomb efficiency is nearly 100%during the long cycle.Overall,the interconnected structure of 3D spiny inorganic heterostructure nanofiber constitutes fast and uninterrupted lithium ions transport channels,maximizing the synergistic effect of interfacial transport of inorganic fillers and reducing PEO crystallinity,thus providing a novel approach to high performance solid-state electrolytes.
文摘The valence electron structures of Sr- and Mg-doped LaGaO3 ceramics with different compositions were calculated by Empirical Electron Theory of Solids and Molecules （EET）. A criterion for the ionic conductivity was proposed, i.e. the 1/（nAnB） increases with increasing the ionic conductivity when x or y〈20% （in molar fraction）.
基金financial support from the National Key Research and Development Program of China(2017YFA0206904,2017YFA0206900)start-up fund of Changchun Institute of Applied Chemistry,Chinese Academy of Sciences
文摘The ionic conductivity and the mechanical strength are two key factors for the performance of poly（ethylene oxide）（PEO） based polyelectrolytes. However, crystallized PEO suppresses ion conductivity at low temperature and melted PEO has low mechanical strength at high temperature. Here, random binary brush copolymer composed of PEO-and polystyrene（PS）-based side chains is synthesized. PEO crystallinity is suppressed by the introduction of PS brushes. Doping with lithium trifluoromethanesulfonate（Li Tf） induces microphase separation. Due to a random arrangement of the brushes, the microphase segregation is incomplete even at high salt loading, which provides both high ionic conductivity and high mechanical strength at room temperature. These results provide opportunities for the design of polymeric electrolytes to be used at room temperature.
