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Solid Polymer Electrolytes (solid + polymer_electrolyte)
Selected AbstractsThermal and transport properties of the polymer electrolyte based on poly(vinyl alcohol)-LiOH-H2OPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 10 2005I. Delgado Abstract Solid polymer electrolytes consisting of poly(ethylene oxide) PEO and lithium trifluroacetate (CF3COOLi) with various salt mass fractions were prepared by the solvent casting method using acetonitrile. Temperature and concentration dependent impedance spectroscopy, as well as thermal analysis suggest the existence of a complex in the blends with an EO/Li ratio corresponding roughly to 4:1. The dc conductivity (,0) of the blends were very sensitive to the temperature (T) and their salt mass fraction (x), showing values in the range of 10-5 to 10-2 (S cm,1) at 330 K as the salt concentration was increased. The enhancement of conductivity with increasing temperature (5 orders of magnitude when the temperature changes from 300 to 353 K) was attributed to the high mobility of the Li+ ions as a consequence of the chain polymer flexibility and the increase of the free volume for ionic migration. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Crystallinity, thermal properties, morphology and conductivity of quaternary plasticized PEO-based polymer electrolytesPOLYMER INTERNATIONAL, Issue 3 2007Yan-Jie Wang Abstract Quaternary plasticized solid polymer electrolyte (SPE) films composed of poly(ethylene oxide), LiClO4, Li1.3Al0.3Ti1.7(PO4)3, and either ethylene carbonate or propylene carbonate as plasticizer (over a range of 10,40 wt%) were prepared by a solution-cast technique. X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS) indicated that components such as LiClO4 and Li1.3Al0.3Ti1.7(PO4)3 and the plasticizers exerted important effects on the plasticized quaternary SPE systems. XRD analysis revealed the influence from each component on the crystalline phase. DSC results demonstrated the greater flexibility of the polymer chains, which favored ionic conduction. SEM examination revealed the smooth and homogeneous surface morphology of the plasticized polymer electrolyte films. EIS suggested that the temperature dependence of the films' ionic conductivity obeyed the Vogel,Tamman,Fulcher (VTF) relation, and that the segmental movement of the polymer chains was closely related to ionic conduction with increasing temperature. The pre-exponential factor and pseudo activation energy both increased with increasing plasticizer content and were maximized at 40 wt% plasticizer content. The charge transport in all polymer electrolyte films was predominantly reliant on lithium ions. All transference numbers were less than 0.5. Copyright © 2006 Society of Chemical Industry [source] Ionic conductivity in poly (L-leucine)1,3-diamino propane,lithium iodide solid polymer electrolytePOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 3 2009N. H. Kaus Abstract The pelletized Poly(L-Leucine)-1,3-diamino propane,lithium iodide (LiI) samples have been prepared by using a low temperature sintering method. Results from impedance spectroscopy have proven this mixture to be a superionic material with maximum conductivity obtained in the range of 10,3,S/cm for the samples containing 50,wt% LiI. The high ionic conductivity achieved was due to the increased number of charge carrier from LiI. Improved conductivity could also be due to hopping of lithium ion through the side chain of polymer. Infrared spectroscopy showed that both LiI and poly amino acid may co-exist together. From the spectra it is revealed that the CO band at 1643,cm,1 shifted to higher wave number indicating that chelation of Li+ may have occurred at oxygen atom. Results from X-ray diffraction show that the prepared samples were partially crystalline in nature. Some of the peaks have disappeared and this confirmed that some complexation has occurred within the sample. Copyright © 2009 John Wiley & Sons, Ltd. [source] Ionic conductivity of solid polymer electrolytes for dye-sensitized solar cellsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2010Joo Wan Kim Abstract We developed an ionic conductivity model of solid polymer electrolytes for dye-sensitized solar cells (DSSCs) based on the Nernst,Einstein equation in which the diffusion coefficient is derived from the molecular thermodynamic model. We introduced concentration-dependence of the diffusion coefficient into the model, and the diffusion coefficient was expressed by differentiating the chemical potential by concentration. The ionic conductivities of polymer electrolytes (PEO/LiI/I2 system) were investigated at various temperatures and compositions. We prepared a set of PEO in which an EO : LiI mole ratio of 10 : 1 was kept constant for PEO·LiI·(I2)n compositions with n = 0.02, 0.05, 0.1, 0.15, 0.2, and 0.3 (mole ratio of LiI : I2). The ionic conductivities of the electrolytes were measured using a stainless steel/polymer-electrolyte/stainless steel sandwich-type electrode structure using alternating current impedance analysis. The values calculated using the proposed model agree well with experimental data. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Spherulitic superstructure and morphology of poly(ethylene oxide),lithium perchlorate complexPOLYMER COMPOSITES, Issue 12 2008Xiaobin Huang The morphology of solid polymer electrolytes based on PEO-LiClO4 complex was investigated by polarized optical microscopy (POM). The spherulitic structure derived from POM suggested that the ion induces different spherulitic structures. An interesting turning point of salt concentration has been found. At the turning point, the complex was amorphous. The melting point, size, and growth rate of the spherulite decreased with increasing of salt concentration before the turning point and began to increase after the turning point. The multiphase structure of the complexes have been deduced and proved by X-ray diffraction. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers [source] Preparation and characterization of novel hybrid thermoplastic poly(ether urethane)/poly(vinylidene fluoride) elastomers, and their application as solid polymer electrolytesPOLYMER INTERNATIONAL, Issue 5 2007Ye Lin Abstract A comb-like polyether, poly(3-2-[2-(2-methoxyethoxy)ethoxy]ethoxymethyl-3,-methyloxetane) (PMEOX), was reacted with hexamethylene diisocyanate and extended with butanediol in a one-pot procedure to give novel thermoplastic elastomeric poly(ether urethane)s (TPEUs). The corresponding hybrid solid polymer electrolytes were fabricated through doping a mixture of TPEU and poly(vinylidene fluoride) with three kinds of lithium salts, LiClO4, LiBF4 and lithium trifluoromethanesulfonimide (LiTFSI), and were characterized using differential scanning calorimetry, thermogravimetric analysis and Fourier transform infrared spectroscopy. The ionic conductivity of the resulting polymer electrolytes was then assessed by means of AC impedance measurements, which reached 2.1 × 10,4 S cm,1 at 30 °C and 1.7 × 10,3 S cm,1 at 80 °C when LiTFSI was added at a ratio of O:Li = 20. These values can be further increased to 3.5 × 10,4 S cm,1 at 30 °C and 2.2 × 10,3 S cm,1 at 80 °C by introducing nanosized SiO2 particles into the polymer electrolytes. Copyright © 2006 Society of Chemical Industry [source] | ||||||||||