Good Interfacial Stability Research Articles

Nanofiltration membranes with dually charged composite layer exhibiting super-high multivalent-salt rejection

State-of-the-art nanofiltration (NF) membranes generally positively or negatively charged could not remove both multivalent cations and anions once and for all according to the Donnan Exclusion. Designing NF membranes with facile approach for effective removal of multivalent-salt without compromising the permeation is still a tough challenge. In this work, we demonstrate a sort of novel NF membrane consists of a positively charged interlayer sandwiched between substrate and negatively charged outermost surface. The restructured NF membranes with dually charged composite layer were fabricated via amination-interfacial polymerization (A-IP) on poly (vinyl chloride) (PVC) substrate. The resultant NF membranes exhibited super high salts rejection of up to 99.0% MgCl2, 99.0% MgSO4, 98.5% CaCl2, 95.7% Pb(NO3)2, and 96.0% Na2SO4. Additionally, reasonably high flux (8.7Lm−2h−1bar−1, (pure water permeability (PWP))) approaching those of commercial NF membranes was obtained due to the relatively loose structure of the composite layer. Furthermore, the transport and separation mechanism of the restructured NF membranes reveals that the significant upgraded separation performance could be attributed to the synergistic effect of the dually charged layer. Moreover, the dually charged composite layer shown none unfavorable interaction and the resultant NF membranes possessed good interfacial stability.

High temperature interfacial phase stability of a Mo/Ti3SiC2 laminated composite

A Mo/Ti3SiC2 laminated composite is prepared by spark plasma sintering at 1300°C under a pressure of 50MPa. Al powder is used as sintering aid to assist the formation of Ti3SiC2. The fabricated composites were annealed at 800, 1000 and 1150°C under vacuum for 5, 10, 20 and 40h to study the composite's interfacial phase stability at high temperature. Three interfacial layers, namely Mo2C layer, AlMoSi layer and Ti5Si3 solid solution layer are formed during sintering. Experimental results show that the Mo/Ti3SiC2 layered composite prepared in this study has good interfacial phase stability up to at least 1000°C and the growth of the interfacial layer does not show strong dependence on annealing time. However, after being exposed to 1150°C for 10h, cracks formed at the interface.

Fabrication and contact resistivity of W–Si3N4/TiB2–Si3N4/p–SiGe thermoelectric joints

The design and fabrication of silicon germanium (SiGe) thermoelectric elements, typically including the selection of electrode and intermediate materials, the process of joining electrode and intermediate layer onto thermoelectric materials, are the major challenge for SiGe thermoelectric device technology. In this study, W–Si3N4 and TiB2–Si3N4 composites are designed as the electrode and intermediate layer, respectively, and the W–i3N4/TiB2–Si3N4/p–Si80Ge20B0.6 joints are fabricated by a one-step spark plasma sintering process. The influences of the composition of TiB2–Si3N4 intermediate layer on the interfacial structure, contact resistivity and interfacial thermal stability are investigated. The interfacial thermal stability is improved with increasing Si3N4 content in TiB2–Si3N4 intermediate layer due to the reduced mismatch of coefficients of thermal expansion between the intermediate layer and SiGe. On the other hand, the contact resistivity increases with the rising of Si3N4 content due to the weakened TiB2/SiGe ohmic contact, which degrades the device efficiency. As the balanced point, the intermediate layer with the composition of 80vol% TiB2+20vol% Si3N4 provides good interfacial thermal stability and moderately small contact resistivity (~75μΩcm2 after aging at 1000°C for 120h) simultaneously, which is an optimized intermediate layer composition for W–Si3N4/TiB2–Si3N4/p–Si80Ge20B0.6 thermoelectric element. The TiB2–Si3N4 intermediate layer has excellent chemical stability to both W–Si3N4 electrode and SiGe thermoelectric material at high temperatures, which contributes to the sharp interface of the joint and effectively prevents the inter-diffusion between the electrode and the SiGe.

The Evaluation Experiment Research on Sp Binary Composite System Performance and the Oil Displacement Effect

SP binary composite system can reduce the interfacial tension, has good viscoelasticity, and has similar displacement effect with ASP ternary composite system. In addition, the scaling formation can be weaken because it does not contain alkali. Therefore, it plays a important role in guiding the formulas of SP binary composite system and designing the injection scheme to evaluate the main performance and oil displacement effect of SP binary composite system. Experiments on the main performance evaluation, microscopic simulation model for oil displacement and oil displacement in cores have been carried in this paper, which is intended for the new type of surfactant (HLX-BO1 type)/polymer binary complex system which is applied in SP binary composite flooding test block of Daqing oil field. The emulsification property, adsorption characteristics, stability and rheological property of the SP binary composite system have been evaluated. The oil displacement effect of polymer flooding, surfactant flooding, and SP binary composite flooding have been analyzed in this paper. The evaluation experimental research on SP binary complex system performance shows that: 1The binary composite system has good viscosity stability and interfacial tension stability. 2the emulsification time and emulsification degree both increase With the increasing of surfactant concentration. 3The higher oil content in the oil sand, the greater the surfactant adsorption capacity. 4The concentration of surfactant has less affect on the apparent viscosity of the polymer solution, while alkali has greater influence on the apparent viscosity of the polymer solution. The oil displacement experimental research on SP binary system shows that the oil displacement effect of SP binary system is significantly better than that of the unitary system of polymer or surfactant alone. The oil displacement effect is well whether SP system is flooded after water flooding or polymer flooding. The average enhanced oil recovery rates of artificial cores in the oil displacement experiment are 17.5% and 10.10% respectively. The average enhanced oil recovery rate of natural cores in the oil displacement experiment after polymer flooding is 9.5%.

Polymer/colloid dual-phase electrolyte membrane for rechargeable lithium batteries

In this work, a polymer/ceramic phase-separation porous membrane is first prepared from polyvinyl alcohol–polyacrylonitrile water emulsion mixed with fumed nano-SiO2 particles by the phase inversion method. This porous membrane is then wetted by a non-aqueous Li–salt liquid electrolyte to form the polymer/colloid dual-phase electrolyte membrane. Compared to the liquid electrolyte in conventional polyolefin separator, the obtained electrolyte membrane has superior properties in high ionic conductivity (1.9 mS cm−1 at 30 °C), high Li+ transference number (0.41), high electrochemical stability (extended up to 5.0 V versus Li+/Li on stainless steel electrode), and good interfacial stability with lithium metal. The test cell of Li/LiCoO2 with the electrolyte membrane as separator also shows high-rate capability and excellent cycle performance. The polymer/colloid dual-phase electrolyte membrane shows promise for application in rechargeable lithium batteries.

Gel polymer electrolyte with ionic liquid for high performance lithium sulfur battery

Poly(vinylidenefluoride-hexafluoropropylene)[P(VDF-HFP)] membrane with porous structure was prepared by a simple phase separation process. The gel polymer electrolyte (GPE) prepared by combining the porous membrane with N-methyl-N-butylpyrrolidinium bis(trifluoromethanesulfonyl)imide ionic liquid shows good thermal stability, high anodic oxidation potential (>5.0V vs. Li/Li+) and good interfacial stability with lithium electrode. The lithium sulfur battery with the GPE delivers an initial discharge capacity 1217.7mAhg−1 and maintains a reversible capacity of 818mAhg−1 after 20cycles at a current density of 50mAg−1.

BAND ALIGNMENT AND ATOM SEGREGATION OF LaYbO3 FILMS ON SILICON

Ternary rare earth oxides are expected to be more promising high-k dielectric materials than conventional binary rare earth oxides due to higher band gap, higher permittivity and good interfacial stability. In the present study, the band alignment and atom thermal diffusion of LaYbO3 , a new ternary rare earth oxide, are studied by X-ray photoelectron spectrum (XPS) and angle-resolved XPS, respectively. The band gap value for LaYbO3 crystalline film rises to 6.7 eV compared with 6.2 eV for amorphous film. Valence (ΔEv) and conduction band (ΔEc) offset are ΔEv = 3.5 eV, ΔEc = 1.6 eV for the amorphous film and ΔEv = 3.3 eV, ΔEc = 2.3 eV for the crystalline film. From elemental depth profile through high-k layer and silicon substrate, it is shown that La atom tends to diffuse into silicon substrate and piles up at oxide/silicon interface at high annealing temperature ~1000°C.

PVC–PMMA composite electrospun membranes as polymer electrolytes for polymer lithium-ion batteries

Composite nanofibrous membranes based on poly (vinyl chloride) (PVC)–poly (methyl methacrylate) (PMMA) were prepared by electrospinning and then they were soaked in liquid electrolyte to form polymer electrolytes (PEs). The introduction of PMMA into the PVC matrix enhanced the compatibility between the polymer matrix and the liquid electrolyte. The composite nanofibrous membranes prepared by electrospinning involved a fully interconnected pore structure facilitating high electrolyte uptake and easy transport of ions. The ion conductivity of the PEs increased with the increase in PMMA content in the blend and the ion conductivity of the polymer electrolyte based on PVC–PMMA (5:5, w/w) blend was 1.36 × 10−3 S cm−1 at 25 °C. The polymer electrolyte based on PVC–PMMA (5:5, w/w) blend presented good electrochemical stability up to 5.0 V (vs. Li/Li+) and good interfacial stability with the lithium electrode. The promising results showed that nanofibrous PEs based on PVC–PMMA were of great potential application in polymer lithium-ion batteries.

Li/LiFePO4 batteries with gel polymer electrolytes incorporating a guanidinium-based ionic liquid cycled at room temperature and 50 °C

Gel polymer electrolytes composed of PVdF-HFP microporous membrane incorporating a guanidinium-based ionic liquid with 0.8molkg−1 lithium bis(trifluoromethanesulfonylimide) are characterized as the electrolytes in Li/LiFePO4 batteries. The ionic conductivity of these gel polymer electrolytes is 3.16×10−4 and 8.32×10−4Scm−1 at 25 and 50°C, respectively. The electrolytes show good interfacial stability towards lithium metal and high oxidation stability, and the decomposition potential reaches 5.3 and 4.6V (vs. Li/Li+) at 25 and 50°C, respectively. Li/LiFePO4 cells using the PVdF-HFP/1g13TFSI-LiTFSI electrolytes show good discharge capacity and cycle stability, and no significant loss in discharge capacity of the battery is observed over 100 cycles. The cells deliver the capacity of 142 and 150mAhg−1 at the 100th cycling at 25 and 50°C, respectively.

Interfacial Stability of a Spark Plasma Sintered Mo-Ti<sub>3</sub>SiC<sub>2</sub> Layered Composite

Mo-Ti3SiC2layered composite was successfully prepared by spark plasma sintering at 1573 K for 20 min under a pressure of 50 MPa in vacuum. The Mo and Ti3SiC2layers were metallurgically bound together without noticeable superficial defects and micro-cracks at the interface. The fabricated Mo-Ti3SiC2layered composite was annealed at 1273 K under vacuum for 5, 10, 20 and 40 h to study the composite’s thermal stability. Three intermediate layers, Mo2C, MoSi2and Ti5Si3Cx, were formed at the interface. Experimental results showed that the Mo-Ti3SiC2layered composite prepared in this study has good interfacial stability at elevated temperature.

Preparation and electrochemical characterization of gel polymer electrolyte based on electrospun polyacrylonitrile nonwoven membranes for lithium batteries

Electrospun membranes of polyacrylonitrile are prepared, and the electrospinning parameters are optimized to get fibrous membranes with uniform bead-free morphology. The polymer solution of 16 wt.% in N, N-dimethylformamide at an applied voltage of 20 kV results in the nanofibrous membrane with average fiber diameter of 350 nm and narrow fiber diameter distribution. Gel polymer electrolytes are prepared by activating the nonwoven membranes with different liquid electrolytes. The nanometer level fiber diameter and fully interconnected pore structure of the host polymer membranes facilitate easy penetration of the liquid electrolyte. The gel polymer electrolytes show high electrolyte uptake (>390%) and high ionic conductivity (>2 × 10 −3 S cm −1). The cell fabricated with the gel polymer electrolytes shows good interfacial stability and oxidation stability >4.7 V. Prototype coin cells with gel polymer electrolytes based on a membrane activated with 1 M LiPF 6 in ethylene carbonate/dimethyl carbonate or propylene carbonate are evaluated for discharge capacity and cycle property in Li/LiFePO 4 cells at room temperature. The cells show remarkably good cycle performance with high initial discharge properties and low capacity fade under continuous cycling.

Effect of adding Ce on interfacial reactions between Sn–Ag solder and Cu

We investigated the effect of adding cerium (Ce) to low Ag content Sn–1.0wt.%Ag solder on the interfacial reactions between the Sn–1.0Ag solder and Cu substrate. The formation and growth of interfacial intermetallic compounds (IMCs) between the Sn–1.0Ag–0.3Ce solder and Cu substrate were studied and the results were compared to those obtained for the Ce-free Sn–1.0Ag/Cu and most promising Sn–3.0Ag–0.5Cu/Cu systems. The addition of Ce to the Sn–Ag solder significantly reduced the growth of the interfacial Cu–Sn IMCs, retarded the interfacial reactions between the solder and the substrate, and prevented the IMC from spalling from the interface. The Sn–1.0Ag–0.3Ce solder alloy had a good interfacial stability with the Cu substrate during solid-state isothermal aging in the viewpoint of IMC growth.

An imidazolium based ionic liquid electrolyte for lithium batteries

An electrolyte for lithium batteries based on the ionic liquid 3-methy-1-propylimidazolium bis(trifluoromethysulfony)imide (PMIMTFSI) complexed with lithium bis(trifluoromethysulfony)imide (LiTFSI) at a molar ratio of 1:1 has been investigated. The electrolyte shows a high ionic conductivity (∼1.2 × 10 −3 S cm −1) at room temperature. Over the whole investigated temperature range the ionic conductivity is more than one order of magnitude higher than for an analogue electrolyte based on N-butyl-N-methyl-pyrrolidinium bis(trifluoromethanesulfonyl)imide (Py 14TFSI) complexed with LiTFSI and used here as a benchmark. Raman results indicate furthermore that the degree of lithium coordinated TFSI is slightly lower in the electrolyte based on PMIMTFSI and thus that the Li + charge carriers should be higher than in electrolytes based on Py 14TFSI. An ionic liquid gel electrolyte membrane was obtained by soaking a fibrous fully interconnected membrane, made of electrospun P(VdF-HFP), in the electrolyte. The gel electrolyte was cycled in Li/ionic liquid polymer electrolyte/Li cells over 15 days and in Li/LiFePO 4 cells demonstrating good interfacial stability and highly stable discharge capacities with a retention of >96% after 50 cycles (∼146 mAh g −1).

Electrochemical performance of electrospun poly(vinylidene fluoride- co-hexafluoropropylene)-based nanocomposite polymer electrolytes incorporating ceramic fillers and room temperature ionic liquid

In view of the safety concerns and the requirements of high energy density lithium batteries, the room temperature ionic liquids (RTILs) are being investigated as suitable candidates to substitute organic electrolytes in polymer electrolytes. In this article, we report synthesis, characterization, and electrochemical properties of nanocomposite polymer electrolytes (NCPEs) comprising of a RTIL [ n-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (BMITFSI)] and nano-sized ceramic fillers (SiO 2, Al 2O 3 or BaTiO 3) hosted in electrospun poly(vinylidene fluoride- co-hexafluoropropylene) [P(VdF-HFP)] membranes. The addition of BMITFSI and ceramic fillers in polymer electrolytes results in high ionic conductivity at room temperature. The cells prepared with BMITFSI and different NCPEs show good interfacial stability and oxidation stability at >5.5 V with the highest value of 6.0 V for the NCPE incorporating BaTiO 3. The cell with the NCPE containing BaTiO 3 delivers high initial discharge capacity of 165.8 mA h g −1, which corresponds to 97.5% utilization of active material under the test conditions, and showed the least % capacity fade after prolonged cycling.

ALL-SOLID-STATE POLYPHOSPHAZENE NANOCOMPOSITE ELECTROLYTE

In order to improve the ambient conductivity of all-solid-state electrolytes as well as enhance the diffusion number of lithium ion,all-solid-state polyphosphazene electrolytes containing nanoSiO_2 modified with poly-(oxyethylene-co-oxypropylene) silane were prepared.The macromonomer of polyphosphazene was prepared through reaction of phosphazene with poly(oxyethylene-co-oxypropylene) monoacrylic ester and poly(ethylene glycol) monomethylether with the yield of 92.6%.Silane coupling agent with polyether was prepared by the hydrosiloxane addition reaction between trimethyloxyl siloxane and allyl poly(ethylene-co-propylene glycol) methyl ether.The silane coupling agent refluxed with SiO_2 to form nanoSiO_2 modified with poly(oxyethylene-co-oxypropylene) silane.The FT-IR spectrum and XPS together show that SiO_2 has been successfully modified by the soft chain.The SEM images of composite electrolytes show that modified nano SiO_2 could easily disperse among polymer electrolyte with only a little conglomeration.It is found that the nanoSiO_2 content in electrolyte fixed at 10% could reach the best ambient conductivity of 3.14×10~(-4) S cm~(-1),which is 2.4 times higher than that of the noncomposite system.Differential scanning calorimetry of nanocomposite solid state electrolytes showed that the glass transition temperature of the electrolyte did not change with the variation of nanoSiO_2 content from 2% to 10%,which indicated that nano SiO_2 modified with polyether did not change the crosslinking density of nanocomposite system,and the polyether chain could maintain the original flexibility of the solid state electrolytes.The conductivity of electrolyte is increasing with the increase of temperature,which obeys the VTF equation.When the temperature rises up to 50℃,the electrolyte with 10% modified SiO_2 shows the best conductivity of 10~(-3) S cm~(-1),the corresponding active energy is 4.07 kJ mol~(-1).The high conductivity can be explained on the one hand,the polyphophazene monomer has the side chain of oxyethylene,which is helpful to solve the lithium salt,the copolymerization of oxyethylene and oxypropylene reduces the glass transition temperature of the polymer and inhibits the crystallization of polyoxyethylene;on the other hand,the nanoparticles modified with soft polyether chains can uniformly disperse in the polymer electrolyte,and the polyether plays the role of plasticizer.The result of DSC also proves such explanation.With increasing the content of lithium salt,the ionic conductivity first increases,then shows a subsequent decline.The highest ambient conductivity of nanocomposite electrolyte is obtained when the concentration of lithium perchlorate is fixed at 8%.The addition of nanoSiO_2 reduces the formation of ion cluster.Cyclic voltammogram gives the result of good electrochemical stability of nanocomposite electrolyte and an electrochemical window of more than 4.2 V.Alternating current impedance spectrum accounts for the good interfacial stability between electrolyte and electrode after 7 days of the assembling of the cell,which was explained by the composition of nanoparticles modified with flexible chains which may reduce the interfacial impedance and help the transfusion of ions.The diffusion number of lithium ion in the nanocomposite all-solid-state polymer electrolyte is realized through stable current method,the result indicates that the ion diffusion number increased from 0.25 to 0.34 due to the composite of nanoparticles.

Properties of the cross-linked composite polymer electrolytes using hyperbranched polymer with terminal acryloyl groups

The cross-linked composite polymer electrolytes composed of poly(ethylene oxide) (PEO), hyperbranched polymer with terminal acryloyl groups (poly-1b), poly(ethylene glycol) methyl ether methacrylate (PEOMA), LiN(CF 3SO 2) 2 were prepared, and their ionic conductivities, mechanical strength, electrochemical and thermal properties, and interfacial stabilities with electrodes were investigated. The ionic conductivity increased with an increase in the PEOMA content in the cross-linked composite polymer electrolyte, and the highest ionic conductivity was obtained at the [80% PEO/20% (poly-1b/PEOMA)] 12(LiN(CF 3SO 2) 2) electrolyte with the poly-1b/PEOMA ratio of 1/3. However, the tensile strength decreased with an increase in the PEOMA content in the cross-linked composite polymer electrolytes. The cross-linked composite polymer electrolyte with the highest ionic conductivity has three times higher tensile strength than non-cross-linked (80% PEO/20% poly-1a) 12(LiN(CF 3SO 2) 2) electrolyte. The addition of the PEOMA unit into the cross-linked composite polymer electrolyte improved both the ionic conductivity and mechanical property at the same time. And also, the cross-linked composite polymer electrolyte containing the PEOMA unit showed the good interfacial stability with both lithium metal and cathode electrodes.

Effect of MgO nanoparticles on ionic conductivity and electrochemical properties of nanocomposite polymer electrolyte

This paper analyzes the comparison between the performances and morphologies of the PMMA gel and composite electrolyte membrane with nanosized MgO particles. These polymer electrolytes were studied in detailed using XRD, DSC, SEM and AC impedance analysis. The conductivity enhancement has been attributed to the addition of ceramic filler that yields a significant increase of surface to volume ratio related to the decrease in glass transition temperature values in the composite polymer electrolyte. Good interfacial stability at the electrode/electrolyte interface resulted on account of the improved ion dissociation by ceramic filler and a rise in the room temperature conductivity (8.14 × 10 −3 S cm −1) due to the iono-covalent or Lewis acid–base bonds to the ions and ether oxygen base groups was also observed. Further enhancement of conductivity has been observed on MgO surface, as Lewis-acidic sites interact with both PMMA and ClO 4 − ions. The percentage of swelling was found to increase with increasing soaking periods upto 12 h. Beyond that soaking period, it was found that there was a negligible increase in the % of swelling.

Influence of Finely Dispersed Carbon Nanotubes on the Performance Characteristics of Polymer Electrolytes for Lithium Batteries

Electrospun membranes of poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP)/multiwall carbon nanotube (MWCNT) composite are prepared and loaded with lithium salts from electrolyte solution. Field emission transmission electron microscopy provides evidence for the uniform distribution of MWCNTs into the matrix of PVdF-HFP. The interconnected morphology as evident from field emission scanning electron micrograph forms the path for the lithium ion conduction. Results from electrochemical impedance spectroscopy inform that the presence of MWCNTs in PVdF-HFP matrix improves interfacial stability between lithium electrode and membrane and augment conduction path in the polymer electrolyte membrane. Further results from impedance measurement reveal the contribution of MWCNTs toward conductivity. A prototype cell is fabricated with PVdF-HFP/MWCNT as polymer electrolyte. The electrospun PVdF-HFP electrolyte membrane with 2% MWCNTs content shows an ionic conductivity of about 5.85 mSmiddotcm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> at 25 degC. Also, PVdF-HFP/MWCNT electrolyte membrane exhibits good electrochemical and interfacial stability and can be potentially suitable as electrolyte in lithium ion secondary battery

Crosslinkable fumed silica-based nanocomposite electrolytes for rechargeable lithium batteries

Electrochemical and rheological properties are reported of composite polymer electrolytes (CPEs) consisting of dual-functionalized fumed silica with methacrylate and octyl groups + low-molecular weight poly(ethylene glycol) dimethyl ether (PEGdm) + lithium bis(trifluoromethanesulfonyl)imide (LiTFSI, lithium imide) + butyl methacrylate (BMA). The role of butyl methacrylate, which aids in formation of a crosslinked network by tethering adjacent fumed silica particles, on rheology and electrochemistry is examined together with the effects of fumed silica surface group, fumed silica weight percent, salt concentration, and solvent molecular weight. Chemical crosslinking of the fumed silica with 20% BMA shows a substantial increase in the elastic modulus of the system and a transition from a liquid-like/flocculated state to an elastic network. In contrast, no change in lithium transference number and only a modest decrease (factor of 2) on conductivity of the CPE are observed, indicating that a crosslinked silica network has minimal effect on the mechanism of ionic transport. These trends suggest that the chemical crosslinks occur on a microscopic scale, as opposed to a molecular scale, between adjacent silica particles and therefore do not impede the segmental mobility of the PEGdm. The relative proportion of the methacrylate and octyl groups on the silica surface displays a nominal effect on both rheology and conductivity following crosslinking although the pre-cure rheology is a function of the surface groups. Chemical crosslinked nanocomposite polymer electrolytes offer significant higher elastic modulus and yield stress than the physical nanocomposite counterpart with a small/negligible penalty of transport properties. The crosslinked CPEs exhibit good interfacial stability with lithium metal at open circuit, however, they perform poorly in cycling of lithium–lithium cells.

Solvent-Free Composite PEO-Ceramic Fiber/Mat Electrolytes for Lithium Secondary Cells

Solvent-free composite poly(ethylene oxide) (PEO)-ceramic fiber or mat electrolytes with high ionic conductivity and good interfacial stability have been developed using high-ionic-conductivity fibers and mats. The conducting ceramic fibers can penetrate the cross section of the electrolyte film to provide long-range lithium-ion transfer channels, thus producing composite electrolytes with high conductivity. In this work, a maximum room-temperature conductivity of S cm−1 was achieved for 20 wt % fiber in a PEO- mixture containing 12.5 wt % in PEO. The maximum transference number obtained was 0.7. The ceramic fibers in this composite electrolyte are coated by a very thin PEO layer, which is sufficient to provide good interfacial stability with lithium-ion and lithium-metal anodes. © 2004 The Electrochemical Society. All rights reserved.