Preparation of Lithium Ion Conductor Glass-Ceramic with High Conductivity for Producing Lithium-Air and all-Solid-State Lithium-Ion Batteries

In this research, new lithium ion conductor glass-ceramics with NASICON-type structure (Li1+x+yAlxCryGe2-x-y (PO4)3, x+y=0.5) were synthesized using melt-quenching method and converted to glass-ceramics through heat treatment. Influence of addition of different concentrations of aluminum and chromium in LiGe2(PO4)3 glass-ceramic was investigated for ionic conduction improvement. Substitution of Ge4+ ions in NASICON structure by Al3+ and Cr3+ ions induced more Li+ ions in A2 vacant sites to obtain charge balance and also changed the unit cell parameters. These two factors led to ionic conductivity improvement of synthesized glass-ceramics. The glass-ceramics were characterized and the amorth structures were investigated by X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Energy-Dispersive X-ray spectroscopy (EDX), Differential Scanning Calorimetry (DSC) and Complex Impedance Spectroscopy (CIS). The highest lithium ion conductivity of 8.82×10-3 S/cm was obtained for x=0.4 and y=0.1 (Li1.5Al0.4Cr0.1Ge1.5(PO4)3) crystallized at 850 oC for 8 h with minimum activation energy of 0.267 eV. &nbsp

Phase equilibrium modeling of structure H clathrate hydrates of methane + water "insoluble" hydrocarbon promoter using group contribution-support vector machine technique

In this work, the group contribution (GC) method is coupled with the least-squares support vector machine (LSSVM) mathematical algorithm to develop a model for representation/prediction of the dissociation conditions of structure H (sH) clathrate hydrates of methane with 21 hydrocarbon promoters namely as water "insoluble" promoters. Almost all of available literature data are studied to present a reliable model validated by the following statistical parameters: absolute average relative deviations (AARD) of the represented/predicted dissociation pressures from the reported experimental values: about 1.6%, and squared correlation coefficient: 0.99. © 2011 American Chemical Society.Ali Eslamimanesh, Farhad Gharagheizi, Amir H. Mohammadi, Dominique Richon, Mohammad Illbeigi, Alireza Fazlali, Amir Ahmad Forghani, and Mohammad Yazdizade