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In the present work, a new methodology for improving the ionic conductivity and cation transport properties of polymer electrolytes have been synthesized by adding bulky anion based novel lithium bisnonafluoro-1-butanesulfonimidate salt and characterized for its applications in lithium ion batteries. The self-standing solid polymer electrolyte films exhibit excellent mechanical, thermal, and electrochemical stability. The ion–polymer interactions are examined thoroughly by ATR Fourier Transform-Infra Red Spectroscopy. The solid polymer electrolyte prepared with EO/Li ratio 14 exhibits a highest ionic conductivity of 10−4 S cm−1 at 333 K. Also, it achieves a maximum lithium transference number of 0.31 and it is electrochemically stable in the scanned electrochemical window. This new type of polymer electrolytes with high ion conductivity and improved mechanical properties paves way to be a potential candidate along with lithium anode and LiCoO2 cathode in the lithium ion batteries.

In this present investigation, we developed a new category of rhodanide anion based ternary gel polymer electrolytes (TILGPEs) with high electrochemical and thermal stability, which advantageously use the harmonizing properties of a temperature-responsive polymer poly vinylidene fluoride-co-hexafluoropropylene (PVdF-co-HFP) and room temperature ionic liquid (1-ethyl-3-methylimiazolium rhodanide (thiocyanate), (EMImSCN)). TILGPEs were fabricated using a facile solution cast method by incorporating EMImSCN and lithium rhodanide (LiSCN) into PVdF-co-HFP based membranes. Among the series of electrochemical tests including electrochemical impedance spectroscopy, cyclic voltammetry, linear sweep voltammetry and chronoamperometry, the membrane with 80 wt% electrolyte mixtures (EMImSCN/LiSCN) showed better performance in all aspects. The maximum ionic conductivity was found to be in the order of 2.8 × 10−4 S cm−1 at 298 K. The LiFePO4/TILGPE3/Li cell offered a maximum discharge capacity of 149.8 mA h g−1 at C/10 rate. The inimitable properties allowed the effective use of the rhodanide TILGPEs as active separators for the development of advanced lithium ion batteries.

Pb-free ferroelectric (Na0.5Bi0.5)TiO3 (NBT) thin films were prepared by a modified sol-gel process. Their structural, dielectric and pyroelectric properties were investigated as a function of the excess Na/Bi ratio and the annealing temperature. In the case of thin films containing no excess Na and Bi, only partial amounts of the perovskite NBT were crystallized, where the films consisted mainly of the pyrochlore phase of Bi2Ti2O7 for annealing conditions of 600~800 o C. With increasing excess Na/Bi ratio, the proportion of the perovskite phase effectively increased due to the compensation of the volatile Na and Bi components. For a Na/Bi ratio of 2.0, the thin film with single NBT perovskite phase was obtained within XRD detection limit after annealing at 700 o C for 10 min and it showed the excellent dielectric properties, er of ~550 and tan δ of 0.03. While these properties were degraded for Na/Bi ratio of 2.5 despite the existence of pure perovskite phase. The NBT thin film with Na/Bi ratio of 2.0 are also promising candidates for applications requiring pyroelectric devices because it was found to have pyroelectric coefficients of 1.3~7 nC/cm 2 K in the temperature range of 30~100 o C.

All-in-one adhesives were recently developed for reducing the technique sensitivity and chair time, but lots of concerns were made on bondability, longevity, and microleakage. The object of this study was to evaluate microleakage and marginal quality of all-in-one adhesives using electrochemical method and SEM analysis quantitatively. After making Class V cavities, they were bulk filled with Heliomolar(#A1 after surface treatment with three adhesives: Adper Prompt (Group A), One up bond F (Group O), Xeno III (Group X) Electrical conductivity (microamphere, ) was checked two times: before and after cavity filling. Percentage of leaky margin was estimated from SEM image (). The data were statistically analysed: ANOVA and Paired T test for electrical conductivity, Kruskal-Wallis and Mann-Whitney test for marginal quality, Spearman s rho test for checking of relationships between 2 methods. The result were as follows: 1. There was no difference in microleakage between adhesive systems and every specimen showed some of microleakage after filling. 2. Microleakage was reduced about 70% with composite resin filling. 3. Marginal quality was the best in group A. decreasing among groups in the following order: group O, followed by group X. There were significant differences between group A and group X (p=0.015), and between group 0 and group X (p=0.019). 4. There was no relationship between the microleakage measured by electrochemical method and marginal quality measured by SEM analysis. Within the results of this study, there was no difference in microleakage among groups by electrical conductivity. However, significant difference in marginal quality was seen among groups. It was believed that these dissimilar results might be induced because of their own characteristics. Analysis of microleakage needs various methods for accuracy.