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Solid polymer electrolyte blends with varied compositions of poly(ethylene oxide) (PEO)/carboxymethyl cellulose (Na-CMC) in 10/90, 50/50, and 90/10 compositions have been successfully prepared by means of the solution cast technique at room temperature. The modification of the structural, optical, and electrical properties of the prepared blend samples was studied by employing XRD, FTIR, UV-Vis, and electrical impedance spectroscopy methods. X-ray diffraction studies revealed that the crystalline nature gradually transforms into amorphous as the Na-CMC content increases in the sample. The variation of bands noticed in the Fourier transform infrared spectroscope characteristic spectrum of the blends reveals the formation of complexes between the individual polymers. The analysis of optical properties using a UV-Vis spectrometer in the wavelength range of 900–1100nm, shows a gradual decrease in the optical indirect energy band gap with an increase in Na-CMC content in the blend. The study of the electrical properties of the blend carried out in the frequency range 50 Hz–1MHz and temperature range 303K–338K, using an electrical impedance analyzer reveals that, the dielectric constant and loss decrease with the rise in frequency, exhibiting the usual behavior of the polymers. AC conductivity is found to increase with an increase in temperature. The highest value of ionic conductivity is found to be 6.06 × 10−3Scm−1 for the blend with a 10/90 composition. [ABSTRACT FROM AUTHOR]

Designing Solid-State Electrolytes (SSEs) exhibiting high ionic conductivity and high mechanical/thermal stability is the main concern for developing next-generation rechargeable batteries. Here we present the successful synthesis of colorless, transparent, and bubble-free phosphate glasses with high lithium-ion electrical conductivity within the system xLiCl–(1–x)(63Li2WO4–37P2O5) with 0 ≤ x ≤ 30 mol%. The structural study is performed using Raman spectroscopy. Electrical conductivity measurements of the glasses are investigated over a large frequency range at various temperatures using impedance spectroscopy. It is found that the electric conductivity increases with increasing lithium chloride content. The dc conductivity reaches 2.76 × 10−6 (Ω−1.cm−1) at room temperature (RT) for the glass (x = 30 mol%). The frequency dependence of the conductivity is investigated and the scaling of the conductivity spectra shows that the conduction mechanism in the glasses is both temperature and composition-independent. [ABSTRACT FROM AUTHOR]

Solid Electrolytes (SOE) with high ionic conductivity highly desirable in order to improve the efficiency of SOFCs at lower functioning temperature range) (350–500 °C). Triple perovskite Ba3SrNb2O9 based proton ion conductor have up-and-coming to enhance ionic conductivity at Low temperature range (LT) (350–500 °C). With this motivation we have successfully synthesized Ba3SrNb2O9 (BSNO) by solgel combustion method. Powder X-ray diffraction (XRD) confirms the formation of Triclinic crystal structure having space group P1, having lattice dimensions (a = 5.89340 Å, b = 5.88760 Å, c = 7.27360 Å). Rietveld Refinement of XRD data was carried out to get detail structural information by Full-Prof suite software. Electrical performance of the BSNO system were systematically studied by Electrochemical Impedance spectroscopy at functioning temperature 350–500 °C with interval of 50 °C. BSNO system exhibit conductivity of the order of 5.8 × 10−3 Scm−1 at 500 °C with the activation energy of the range of 0.48 eV. Charge Relaxations phenomenon very systematically explored by impedance loss spectra and it is very correlate with Modulus (M") as a function of frequency at several temperatures which used to clarify the charge relaxation dynamics in proton ion conducting BSNO material. [ABSTRACT FROM AUTHOR]

In this study, a modified sol-gel method was employed to synthesize Gd and W co-doped La2Mo2O9 (LMX). The impact of Gd and W co-doping on the pristine LMX lattice was examined using X-Ray diffraction, and the local structural parameters were analyzed through Rietveld refinement. The findings indicate that both the pure and co-doped LMX samples possess a cubic structure with a P213 space group. To investigate the electrical performance of the lanthanum molybdate (La2Mo2O9) both in its pure form and when co-doped with Gd and W, electrochemical impedance spectroscopy was conducted. The results demonstrated that co-doping enhances the conductivity of oxy-ions compared to pure LMX. Specifically, La1.7Gd0.3Mo1.7W0.3O9 (LMXG3) exhibited a higher ionic conductivity of approximately 2 x 10−2 Scm−1 at a temperature of 650 °C, surpassing the conductivity of the pure LMX sample and other co-doped LMX samples. This investigation highlights the potential of the Gd and W co-doped LMX system as a solid electrolyte for intermediate-temperature solid oxide fuel cells (IT-SOFCs). [ABSTRACT FROM AUTHOR]

Solid polymer electrolytes (SPEs) have been recognized as a preferable alternative to liquid electrolytes for energy storage application. However, low conductivity of SPEs has restricted their application. This issue can be overcome by adding controlled amount of dopant salt to the SPEs. In this work, various concentration of ammonium thiocyanate (NH4SCN) salt was incorporated into dextran using solution cast technique in order to study the effect of NH4SCN on electrical properties, crystallite size, morphology and ionic conductivity. Results from Fourier-transform infrared (FTIR) analysis confirm the coordination of cation of salt at the OH and C-O-C groups of dextran. Deconvolution of the FTIR band between 2015 and 2090 cm−1 was performed to investigate the ion association and dissociation phenomena. It is confirmed that the ion mobility and diffusion are directly proportional to the ionic conductivity. Based on the electrochemical impedance spectroscopy (EIS) result, an optimum ionic conductivity of (3.18 ± 1.19) × 10−4 S cm−1 was achieved with the sample containing 40 wt.% salt concentration. The conductivity result can be clarified by the crystallite size obtained from X-ray diffraction (XRD) analysis and field emission scanning electron microscopy (FESEM) images. [ABSTRACT FROM AUTHOR]

Solid polymer electrolytes were prepared using polymethyl methacrylate (PMMA), ethylene carbonate (EC), lithium trifluoroethane-sulfonate (LiTf), magnesium trifluoro-methanesulfonate (MgTf2). The ionic conductivity was measured at 30 °C as 6.17 × 10−6 and 1.83 × 10−4 S cm−1, respectively. The ionic mobility (μ), charge carrier diffusion coefficient (D) and the ion number density (n) of the samples have been calculated to understand the effect of these parameters on the ionic conductivity. The experimentally obtained values of Z r and Z i are compared with theoretical calculations. The PMMA-EC-MgTf2 sample exhibits higher dielectric constant compared to PMMA-EC-LiTf. The MgTf2 containing sample also exhibits a higher transference number. [ABSTRACT FROM AUTHOR]

Poly(acrylamide-co-acrylic acid) (PAAm-PAA) based solid polymer electrolytes (SPEs) containing potassium iodide (KI) have been prepared. The complexation between PAAm-PAA and KI has been identified through the position changes at the asymmetric NH2 stretching and CH2 stretching; and the intensities changes at the amide (C = O, C-N) and carboxylate (COO-) bands using Fourier transform infrared (FTIR) spectroscopy. PAAm-PAA film exhibits a room temperature (RT) ionic conductivity of (8.8 ± 0.8) × 10−11 S·cm−1 which increases to maximum at (4.0 ± 0.5) × 10−7 S·cm−1 with 45 wt.% KI addition. The conductivity-temperature dependence studies of all samples followed the Arrhenius rule. [ABSTRACT FROM AUTHOR]

In this article, the complexation of methylcellulose (MC) with tri-potassium phosphate (K3PO4) is investigated using an ultrasonication-assisted solution cast process. X-ray diffraction (XRD) analysis indicates that varying concentrations of K3PO4 salt (7–35 wt.%) disrupt the crystalline segment of the MC host matrix. The considerable shift in the intensity and orientation of the Fourier transforms infrared spectroscopy (FTIR) transmittance bands indicate the establishment of a charge-transfer entanglement between the polymer host and the dispersed salt. The optimum sample (28 wt.%) exhibits a high ionic conductivity of 1.74 × 10−5 S cm−1, potential stability of 3.48 V, and a cation transference number (ti) of 0.945. These findings show the relevance of the developed SPEs for possible application in electrochemical devices. [ABSTRACT FROM AUTHOR]

Understanding the transport mechanism of Li+ in solid polymer electrolytes is beneficial for improving the safety and energy density of lithium-ion batteries. In this work, we investigate the effects of chain length of poly (ethylene oxide) (PEO) and anions (TfO-, TFSI-, PFSI-) on ion transport properties in PEO-lithium salt systems using all-atom molecular dynamics simulations. We found that the Li+ and PEO monomers are co-diffusion, regardless of the PEO chain length and the type of anion. The diffusion of Li+ becomes slower with PEO chain length and reaches an asymptotic value. In addition, the motion of the Li+ is the slowest in PEO/LiTfO systems. We conclude that the free volume of the systems plays a decisive role in the transport properties of Li+. [ABSTRACT FROM AUTHOR]

Contemporary electrolyte additives have captivated the attention of researchers since additives were reported to play a very crucial role in supporting the formation of an effective solid electrolyte interphase (SEI) in the case of silicon if used as an anode. The choice of a good solvent with additives demonstrates a significant impact on the solvation and diffusivity of lithium ions. Fluoroethylene carbonate (FEC) and Vinylene carbonate (VC) were extensively used additives for increasing the lifespan of Li-ion batteries (LIBs). In the current study, structural, dynamical, and transport properties of six different systems were investigated by applying classical molecular dynamics (MD) simulations. The properties obtained from the simulations suggested system E consisting of DMC, 1M LiPF 6 , and 10% FEC, to be the best medium for the electrolytes for LIBs, since the diffusion coefficient of Li + ions and ionic conductivity of LiPF 6 were estimated to be of high values for the system E. However, before the evaluation of the transport properties, the structural properties in terms of radial distribution functions and spatial distribution functions were evaluated for DMC molecules with reference to DMC, Li + , and PF 6 − ions. The structure data were also found to be in fair agreement with experimental and previous simulation results reported so far. Based on the finding of this study, it was suggested that DMC as a solvent with a 10% FEC additive could be considered a good medium for electrolytes for the improved performance of LIBs compared to VC as an additive to DMC. [ABSTRACT FROM AUTHOR]

As a prospective electrolyte for potassium-ion batteries, porous polymer electrolytic membranes were prepared based on poly (vinylidene difluoride-co-hexafluoropropylene) (PVDF-co-HFP) by a solution cast method. The casting solution, effects of the solvent, non-solvent and addition of nanoscale TiO2 particles were investigated in this study. The membranes were characterized by scanning electron microscopy (SEM) results in the surface morphology and porous nature of the fabricated membrane. X-ray diffraction (XRD) analysis gives the crystalline phase of the TiO2 doped membrane. The FTIR confirms the different functional groups present in PVDF-co-HFP films. Electrochemical stability of the prepared PVDF-co-HFP-TiO2 was performed by thermogravimetric analysis (TGA). The charge and discharge tests were conducted using the cyclic voltammetric analysis in this study. The addition of TiO2 particles to the polymer electrolyte was found to reduce the porousness of the PVDF-co-HFP membrane and to enhance the electrolyte uptake, ion conductivity and electrolyte/electrode interfacial stability of the membrane. [ABSTRACT FROM AUTHOR]

All-solid-state Li-ion batteries, have become increasingly important because of their highly reliable solid electrolyte materials. Flexible solid polyethylene oxide (PEO) based electrolytes have been widely studied. Nevertheless, this material exhibits low lithium-ion conductivity. Herein, we report the optimisation of the composition of PEO/polyvinylidene fluoride (PVDF)-based electrolytes to enhance ionic conductivity. When the weight ratio of lithium bis(trifluoromethane sulphonyl)imide and PEO/PVDF is 1:5 (LiTFSI:PEO/PVDF = 1:5), maximum conductivities are 2.98 × 10−5 S cm−1 at 30°C and 5.56 × 10−4 S cm−1 at 60°C. Furthermore, the all-solid-state battery using this solid electrolyte film, a Li metal anode, and a LiFePO4 cathode delivers initial discharge capacities of 149.6 mAhg−1 (0.1 C, 60°C) and 130.2 mAh g−1 (0.5 C, 60°C). Meanwhile, the solid-state lithium battery also presents good cycling performance and excellent rate capability at 60°C. [ABSTRACT FROM AUTHOR]

Recently, solid polymer electrolytes (SPEs) are of great current interest as substitutes to conventional liquid type electrolytes. Although the SPEs significantly alleviate the safety issues of the lithium-ion batteries based on conventional liquid electrolytes, they intrinsically exhibit low ion conductivity. In this study, a bicontinuous solid polymer electrolyte containing polyacrylonitrile (PAN) membrane and a mixture of succinonitrile (SN) and lithium bis(trifluoromethanesulfonyl)imide was prepared with different molarities of the lithium salt. Porous PAN membrane was fabricated via a thermally induced phase separation method (TIPS). The PAN-based SPE exhibited the maximum ionic conductivity of ∼5.0 × 10−3 S/cm at the salt molarity of 1.0 M. [ABSTRACT FROM AUTHOR]

XRD measurements revealed that the investigated NaLiMnP2O7 compound consists of two phases: Na2Mn3(P2O7)2 and LiMnPO4. We found by XRD measurements that at 313 K Na2Mn3(P2O7)2 shows the triclinic symmetry of the compound (space group P-1), while LiMnPO4 phase showed the orthorhombic crystal symmetry (space group Pnma). The phase change between 773 K and 813 K was proved by thermal XRD, impedance spectroscopy and DTA analysis. No evident changes of peak intensities in thermal XRD were observed for LiMnPO4 phase. The impedance of NaLiMnP2O7 ceramics was measured at different temperatures and the total ionic conductivity of the compound was found to be of 5.3 × 10−9 S/m at 400 K on heating stage and only slightly higher on cooling stage. However, the conductivity value at 800 K was much higher – about 1.45 S/m on both stages. The step-like phase transition resulted in the conductivity increase of about 3 orders of magnitude in a narrow range of temperature. The ionic transference number was found to be 0.91 at room temperature. The XRD spectra and conductivity analysis of synthesised two separate phases showed that the phase transition takes place only in Na2Mn3(P2O7)2 ceramics. [ABSTRACT FROM AUTHOR]

Triblock copolymers comprising chemically complementary poly(ethylene oxide)/polyacrylamide (TBC) and their partially hydrolyzed derivative (TBChydr) were investigated as possible ion-conducting membranes for Li-ion batteries (LBs), dye-sensitized solar cells (DSSCs) and fuel cells (PEFCs). Two TBC samples consisting PEO blocks of variable block length (MnPEO = 6·104 and 3.5·104 kDa) were synthesized and used for these purpose. It was noticed that ionic conductivity of TBC membranes increases with PEO block lengthening from 6.2·10−11 to 3.2·10−9 S⋅cm−1. The introduction of additional ionic groups -COOH in polyacrylamide block of TBC has a positive effect on the conductive characteristics of copolymer membranes. The ionic conductivity of TBC membranes filled with LiPF6 increases with increasing of salt content. [ABSTRACT FROM AUTHOR]

We present a computational approach for identifying the important descriptors of the ionic conductivities of lithium solid electrolytes. Our approach discriminates the factors of both bulk and grain boundary conductivities, which have been rarely reported. The effects of the interrelated structural (e.g. grain size, phase), material (e.g. Li ratio), chemical (e.g. electronegativity, polarizability) and experimental (e.g. sintering temperature, synthesis method) properties on the bulk and grain boundary conductivities are investigated via machine learning. The data are trained using the bulk and grain boundary conductivities of Li solid conductors at room temperature. The important descriptors are elucidated by their feature importance and predictive performances, as determined by a nonlinear XGBoost algorithm: (i) the experimental descriptors of sintering conditions are significant for both bulk and grain boundary, (ii) the material descriptors of Li site occupancy and Li ratio are the prior descriptors for bulk, (iii) the density and unit cell volume are the prior structural descriptors while the polarizability and electronegativity are the prior chemical descriptors for grain boundary, (iv) the grain size provides physical insights such as the thermodynamic condition and should be considered for determining grain boundary conductance in solid polycrystalline ionic conductors. [ABSTRACT FROM AUTHOR]

Although all-solid-state batteries have good safety and high energy density, they still need to explore high performance solid-state electrolytes to achieve high ionic conductivity, wide electrochemical window and excellent mechanical properties. In this work, we designed a hybrid solid electrolyte to solve these problems via mixing PEO, ionic liquid EmimFSI (1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide), LLZO (Li6.5Mg0.05La3Zr1.6Ta0.4O12) and lithium salt, which aimed at suppression of PEO crystallization and employed to improve the mechanical and electrochemical stability. Accordingly, the LLZO@EmimFSI@PEO derived hybrid solid electrolyte provides an ionic conductivity of 1.0×10-4 S cm-1 at 40oC and electrochemical stability window above 5.0 V vs. Li/Li+. Furthermore, the symmetric cell of Li/hybrid solid electrolyte/Li exhibits flat voltage profiles and stable lithium plating/stripping process, a solid-state battery based on the hybrid solid electrolyte combined with high-energy lithium metal anode and NCM622 (LiNi0.6Co0.2Mn0.2O2) cathode was also demonstrated. [ABSTRACT FROM AUTHOR]

Nb-doped lithium lanthanum titanate (LLTO) ceramic electrolytes were fabricated by the conventional solid-state reaction method. Effects of Nb5+ substitution on the microstructure and ionic conductivity of LLTO were investigated systematically. It is found that the 4 at.% Nb-doped Li0.5La0.5TiO3 sintered at 1350 °C for 12 h shows the minimum amount of pores in microstructure and the highest total conductivity, 1.04 × 10−4 S/cm, being 1.6 times of that without Nb addition. Therefore, it is proved experimentally that a proper amount of Nb doping could be an effective and facile approach to improve the LLTO's microstructure and total conductivity, thus making Nb-doped LLTO a good solid electrolyte candidate for use in lithium-ion batteries. [ABSTRACT FROM AUTHOR]

The cubic garnet solid electrolyte Li7La3Zr2O12(LLZO) is recognised as a promising solid electrolyte for the all solid-state batteries. In this study, an effect of Ru doping to Zr site on electrochemical properties of the cubic LLZO is examined. The Ru-doped LLZO is prepared by a conventional solid-state reaction using Ga as a stabilise agent for the cubic phase. X-ray diffraction, scanning electron microscopy, and electrochemical impedance are used to characterise it. A lattice constant of the Ru-doped LLZO decreases with increase in doping amount of Ru. Also, a formation of perovskite LaRuO3is confirmed in the Ru-doped LLZO. The Li ion conductivity of the Ru-doped LLZO is higher than that of the pure LLZO. The highest ionic conductivity of 2.56 × 10−4 S/cm was obtained in Li7La3Zr1.6Ru0.4O12. A promotion of sintering and shrinkage of lattice constant by the Ru doping would be reason for the improvement of Li ion conductivity in the Ru-doped LLZO. [ABSTRACT FROM AUTHOR]

Samples of bismuth lead vanadium oxide (BIPBVOX) (Bi2V1–xPbxO5.5–x/2)singly substituted system in the composition range 0.05 ≤x≤ 0.20 were prepared by sol–gel synthesis route. Structural investigations were carried out by using a combination of differential thermal analysis (DTA) and powder X-ray diffraction (PXRD) technique. Energy dispersive X-ray spectroscopy analysis (EDXA) of doped samples was carried out to predict the sample purity and doping concentration. Transitions, α↔β, β↔γ and γ′↔γ were detected by XRD, DTA and variation in the Arrhenius plots of conductivity. The ionic conductivity was measured by AC impedance spectroscopy. The solid solutions with compositionx≤ 0.07 undergo α↔β phase transition, at 329 °C and β↔γ phase transition at 419 °C. The highly conducting γ′-phase was effectively stabilized at room temperature for compositions withx≥ 0.17 whose thermal stability increases with Pb content. At 300 °C, the highest value of conductivity 6.234 × 10−5S cm−1was obtained for compositionx= 0.15 and at 600 °C the highest value of conductivity 0.65 S cm−1is observed forx= 0.17. AC impedance plots reveal that the conductivity is mainly due to the grain contribution to oxide ion conductivity. [ABSTRACT FROM AUTHOR]

The biopolymer solid electrolyte has been synthesized and characterized. Potassium iodide (KI) has been added in polymer matrix to develop solid polymer electrolyte. Relationships between electrical, ionic transport parameter and mechanism have been studied in detail. Impedance spectroscopy reveals the detailed electrical studies and ion transport mechanism. The ion dissociation factor is compared with a measured dielectric constant at a fixed frequency. The dielectric data are calculated which support the ionic conductivity data. [ABSTRACT FROM AUTHOR]

Solid State Ionics has its roots essentially in Europe. First foundations were laid by Michael Faraday who discovered the solid electrolytes Ag2S and PbF2 and coined terms such as cation and anion, electrode and electrolyte. In the 19th and early 20th centuries, the main lines of development toward Solid State Ionics, pursued in Europe, concerned the linear laws of transport, structural analysis, disorder and entropy and the electrochemical storage and conversion of energy. Fundamental contributions were then made by Walther Nernst, who derived the Nernst equation and detected ionic conduction in heterovalently doped zirconia, which he utilized in his Nernst lamp. Another big step forward was the discovery of the extraordinary properties of alpha silver iodide in 1914. In the late 1920s and early 1930s, the concept of point defects was established by Yakov Il'ich Frenkel, Walter Schottky and Carl Wagner, including the development of point-defect thermodynamics by Schottky and Wagner. In terms of point defects, ionic (and electronic) transport in ionic crystals became easy to visualize. In an ‘evolving scheme of materials science’, point disorder precedes structural disorder, as displayed by the AgI-type solid electrolytes (and other ionic crystals), by ion-conducting glasses, polymer electrolytes and nano-composites. During the last few decades, much progress has been made in finding and investigating novel solid electrolytes and in using them for the preservation of our environment, in particular in advanced solid state battery systems, fuel cells and sensors. Since 1972, international conferences have been held in the field of Solid State Ionics, and the International Society for Solid State Ionics was founded at one of them, held at Garmisch-Partenkirchen, Germany, in 1987. [ABSTRACT FROM AUTHOR]