In order to improve the cycling stability of AB5 type alloy electrodes,rapid quenching technology and new alloy composition design were employed.A hydrogen storage alloy with nominal composition La0.6Ce0.4Ni3.6Co0.65M...In order to improve the cycling stability of AB5 type alloy electrodes,rapid quenching technology and new alloy composition design were employed.A hydrogen storage alloy with nominal composition La0.6Ce0.4Ni3.6Co0.65Mn0.4Al0.2Ti0.05（FeB）0.1 was prepared by vacuum magnetic levitation melting under high purity argon atmosphere,followed by rapid quenching at different cooling rates.XRD results show that all alloys exhibit the single-phase CaCu5-type structure.Electrochemical tests indicate that rapid quenching can slightly improve the cycling life of the alloy.Nevertheless,the high-rate dischargeability of the quenched alloys is lower than that of the as-cast alloy.展开更多
The kinetics of internal chlorination of Ni-Cr-Ce alloy in chlorine at 575℃ has been studied.Internal chlorination of Ni-Cr-Ce alloy occurred to formation of CrCl_(2) and CeCl_(3) solid precipi-tates which is thermod...The kinetics of internal chlorination of Ni-Cr-Ce alloy in chlorine at 575℃ has been studied.Internal chlorination of Ni-Cr-Ce alloy occurred to formation of CrCl_(2) and CeCl_(3) solid precipi-tates which is thermodynamically stable and has lower vapor pressure at the temperature along grain boundaries.At initial corrosion stage,the internal chlorination rate nearly followed parabolic rate law,the internal chlorination was accompanied by the consumption of the alloy by volatilization corrosion which obeyed a linear rate equation,the thickness of the internal chlorination region would be governed by a paralinear rate equation.After a sufficiently long period of corrosion,the rate of internal chlorina-tion would be equal to the rate of overall metal consumption,the depth of internal chlorination approaches a steady state value.Addition of Ce to Ni-Cr alloy increased the degree of internal chlorination.展开更多
Lithium ion batteries （LIBs） represent one of the most promising solutions for environmentally friendly transportation such as electric vehicles. The demand for high energy density, low cost and environmentally frie...Lithium ion batteries （LIBs） represent one of the most promising solutions for environmentally friendly transportation such as electric vehicles. The demand for high energy density, low cost and environmentally friendly batteries makes high-capacity cathode materials very attractive for future LIBs. Layered LiNixCoyMn2O2 （x＋y＋z=1）, Li-rich oxides and Li-V-O compounds have attracted much attention due to their high capacities in recent years. In this review, we focus on the state-of-the-art research activities related to LiNixCoyMn2O2, Li-rich oxides and Li-V-O compounds, including their structures, reaction mechanisms during cycling, challenges and strategies that have been studied to improve their electrochemical performances.展开更多
Porous Co(OH)2 film directly grown on nickel foam is prepared by a facile hydrothermal method.The as-prepared Co(OH)2 film possesses a structure consisting of randomly porous nanoflakes with thicknesses of 20-30 nm.Th...Porous Co(OH)2 film directly grown on nickel foam is prepared by a facile hydrothermal method.The as-prepared Co(OH)2 film possesses a structure consisting of randomly porous nanoflakes with thicknesses of 20-30 nm.The capacitive behavior of the Co(OH)2 film is investigated by cyclic voltammograms and galvanostatic charge-discharge tests in 2 mol/L KOH.The porous Co(OH)2 film exhibits a high discharge capacitance of 935 F g-1 at a current density of 2 A g-1 and excellent rate capability.The specific capacitance keeps a capacitance of 589 F g-1 when the current density increases to 40 A g-1.The specific capacitance of 82.6% is maintained after 1500 cycles at 2 A g-1.展开更多
基金supported by the National High-Tech Research and Development Program of China (No.2006AA11A159)
文摘In order to improve the cycling stability of AB5 type alloy electrodes,rapid quenching technology and new alloy composition design were employed.A hydrogen storage alloy with nominal composition La0.6Ce0.4Ni3.6Co0.65Mn0.4Al0.2Ti0.05（FeB）0.1 was prepared by vacuum magnetic levitation melting under high purity argon atmosphere,followed by rapid quenching at different cooling rates.XRD results show that all alloys exhibit the single-phase CaCu5-type structure.Electrochemical tests indicate that rapid quenching can slightly improve the cycling life of the alloy.Nevertheless,the high-rate dischargeability of the quenched alloys is lower than that of the as-cast alloy.
文摘The kinetics of internal chlorination of Ni-Cr-Ce alloy in chlorine at 575℃ has been studied.Internal chlorination of Ni-Cr-Ce alloy occurred to formation of CrCl_(2) and CeCl_(3) solid precipi-tates which is thermodynamically stable and has lower vapor pressure at the temperature along grain boundaries.At initial corrosion stage,the internal chlorination rate nearly followed parabolic rate law,the internal chlorination was accompanied by the consumption of the alloy by volatilization corrosion which obeyed a linear rate equation,the thickness of the internal chlorination region would be governed by a paralinear rate equation.After a sufficiently long period of corrosion,the rate of internal chlorina-tion would be equal to the rate of overall metal consumption,the depth of internal chlorination approaches a steady state value.Addition of Ce to Ni-Cr alloy increased the degree of internal chlorination.
文摘Lithium ion batteries （LIBs） represent one of the most promising solutions for environmentally friendly transportation such as electric vehicles. The demand for high energy density, low cost and environmentally friendly batteries makes high-capacity cathode materials very attractive for future LIBs. Layered LiNixCoyMn2O2 （x＋y＋z=1）, Li-rich oxides and Li-V-O compounds have attracted much attention due to their high capacities in recent years. In this review, we focus on the state-of-the-art research activities related to LiNixCoyMn2O2, Li-rich oxides and Li-V-O compounds, including their structures, reaction mechanisms during cycling, challenges and strategies that have been studied to improve their electrochemical performances.
基金supported by China Postdoctoral Science Foundation (20100481401)
文摘Porous Co(OH)2 film directly grown on nickel foam is prepared by a facile hydrothermal method.The as-prepared Co(OH)2 film possesses a structure consisting of randomly porous nanoflakes with thicknesses of 20-30 nm.The capacitive behavior of the Co(OH)2 film is investigated by cyclic voltammograms and galvanostatic charge-discharge tests in 2 mol/L KOH.The porous Co(OH)2 film exhibits a high discharge capacitance of 935 F g-1 at a current density of 2 A g-1 and excellent rate capability.The specific capacitance keeps a capacitance of 589 F g-1 when the current density increases to 40 A g-1.The specific capacitance of 82.6% is maintained after 1500 cycles at 2 A g-1.
