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High Rate Capability (high + rate_capability)
Selected AbstractsChemInform Abstract: One-Pot Synthesis of Carbon Nanotube@SnO2,Au Coaxial Nanocable for Lithium-Ion Batteries with High Rate Capability.CHEMINFORM, Issue 7 2009Ge Chen Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] A Kinetic Two-Phase and Equilibrium Solid Solution in Spinel Li4+xTi5O12,ADVANCED MATERIALS, Issue 23 2006M. Wagemaker The zero strain Li4+xTi5O12material as a two-phase system is, in contrast to common knowledge, unstable at room temperature (see figure), and it is fast Li insertion that leads to a kinetically induced effective two-phase reaction. The solid-solution-induced disorder, resulting from the mixed 8a/16c occupation, is most likely responsible for the high rate capabilities in Li4+xTi5O12. [source] High Lithium Electroactivity of Nanometer-Sized Rutile TiO2,ADVANCED MATERIALS, Issue 11 2006Y.-S. Hu Nanometer-sized rutile shows much higher electroactivity towards Li insertion than micrometer-sized rutile. Up to 0.8,mol of Li per mole of TiO2 can be inserted into nanometer-sized rutile at room temperature (see figure), which is able to reversibly accommodate Li up to Li0.5TiO2 with excellent capacity retention and high rate capability on cycling, rendering it a promising anode material for high-power lithium-ion batteries. [source] Li4Ti5O12 Nanoparticles Prepared with Gel-hydrothermal Process as a High Performance Anode Material for Li-ion BatteriesCHINESE JOURNAL OF CHEMISTRY, Issue 6 2010Zheng Qiu Abstract Li4Ti5O12 (LTO) nanoparticles were prepared by gel-hydrothermal process and subsequent calcination treatment. Calcination treatment led to structural water removal, decomposition of organics and primary formation of LTO. The formation temperature of spinel LTO nanoparticles was lower than that of bulk materials counterpart prepared by solid-state reaction or by sol-gel processing. Based on the thermal gravimetric analysis (TG) and differential thermal gravimetric (DTG), samples calcined at different temperatures (350, 500 and 700°C) were characterized by X-ray diffraction (XRD), field emitting scanning electron microscopy (FESEM), transmission electron microscopy (TEM), cyclic voltammogram and charge-discharge cycling tests. A phase transition during the calcination process was observed from the XRD patterns. And the sample calcined at 500°C had a distribution of diameters around 20 nm and exhibited large capacity and good high rate capability. The well reversible cyclic voltammetric results of both electrodes indicated enhanced electrochemical kinetics for lithium insertion. It was found that the Li4Ti5O12 anode material prepared through gel-hydrothermal process, when being cycled at 8 C, could preserve 76.6% of the capacity at 0.3 C. Meanwhile, the discharge capacity can reach up to 160.3 mAh·g,1 even after 100 cycles at 1 C, close to the theoretical capacity of 175 mAh·g,1. The gel-hydrothermal method seemed to be a promising method to synthesize LTO nanoparticles with good application in lithium ion batteries and electrochemical cells. [source] High Power Density Electric Double Layer Capacitor with Improved Activated CarbonCHINESE JOURNAL OF CHEMISTRY, Issue 2 2003Yang Hui Abstract The improvement on commercial activated carbon (AC) through the reactivation under steam in the presence of NiCl2 catalyst leads to the increases of both energy and power densities of electric double layer (dl) capacitors. When AC was treated at 875 °C for 1 h, its discharge specific capacitance increases up to 53.67 F· g,1, an increase of about 25% compared to the as-received AC. Moreover, a significant increase in high rate capability of electric dl capacitor was found after the improvements. Surprisingly, both the treated and untreated AC samples showed similar specific surface area and pore size distribution, but some changes in the surface groups and their concentrations after reactivation were verified by X-photoelectron spectra. Thus, it is reasonable to conclude that the decrease in the surface concentration of the carbonyl-containing species for the improved AC results in an increase of accessibility of the pores to the organic electrolyte ion, causing the enhancements of both the specific capacitance and high rate capability. [source] | ||||||||||