Elevating the upper cutoff voltage to 4.6 V could effec-tively increase the reversible capacity ofLiCoO_(2)(LCO)cathode,whereas the irreversible structural transition,unstable electrode/electrolyte interface and poten...Elevating the upper cutoff voltage to 4.6 V could effec-tively increase the reversible capacity ofLiCoO_(2)(LCO)cathode,whereas the irreversible structural transition,unstable electrode/electrolyte interface and potentially induced safety hazards severely hinder its industrial application.Building a robust cathode/electrolyte interface film by electrolyte engineer-ing is one of the efficient approaches to boost the performance of high-voltage LCO(HV-LCO);however,the elusive interfacial chemistry poses substantial challenges to the rational design of highly compatible electrolytes.Herein,we propose a novel electrolyte design strategy and screen proper solvents based on two factors:highest occupied molecular orbital energy level and LCO absorption energy.Tris(2,2,2-trifluoroethyl)phosphate is determined as the optimal solvent,whose low defluorination energy barrier significantly promotes the construction of LiF-rich cathode/electrolyte interface layer on the surface of LCO,thereby eventually suppresses the phase transition and enhancesLi+diffusion kinetics.The rationally designed electrolyte endows graphite||HV-LCO pouch cells with long cycle life(85.3%capacity retention after 700 cycles),wide-temperature adaptability(-60–80℃)and high safety(pass nail penetration).This work provides new insights into the electrolyte screening and rational design to constructing stable interface for high-energy lithium-ion batteries.展开更多
Based on the method of discrete phase, the law of droplets’ deposition in the last stage stationary blade of a supercritical 600 MW Steam Turbine is simulated in the first place of this paper by using the Wet-steam m...Based on the method of discrete phase, the law of droplets’ deposition in the last stage stationary blade of a supercritical 600 MW Steam Turbine is simulated in the first place of this paper by using the Wet-steam model in commercial software FLUENT, where the influence of inlet angle of water droplets of the stationary blades is also considered. Through the calculation, the relationship between the deposition and the diameter of water droplets is revealed. Then, the amount of droplets deposition in the suction and pressure surface is derived. The result is compared with experimental data and it proves that the numerical simulation result obtained in this paper is reasonable. Finally, a formula of the relationship between the diameter of water droplets and the inlet angle is fit, which could be used for approximate calculation in the engineering applications.展开更多
基金financially supported by National Key Research and Development Program of China(2024YFE0213000)National Natural Science Foundation of China(No.U22A20438)+1 种基金Hubei Natural Science Foundation(2023BAB036,2024BAB103)the Key Research and Development Program of Ningxia Hui Autonomous Region(2024BEE02002).
文摘Elevating the upper cutoff voltage to 4.6 V could effec-tively increase the reversible capacity ofLiCoO_(2)(LCO)cathode,whereas the irreversible structural transition,unstable electrode/electrolyte interface and potentially induced safety hazards severely hinder its industrial application.Building a robust cathode/electrolyte interface film by electrolyte engineer-ing is one of the efficient approaches to boost the performance of high-voltage LCO(HV-LCO);however,the elusive interfacial chemistry poses substantial challenges to the rational design of highly compatible electrolytes.Herein,we propose a novel electrolyte design strategy and screen proper solvents based on two factors:highest occupied molecular orbital energy level and LCO absorption energy.Tris(2,2,2-trifluoroethyl)phosphate is determined as the optimal solvent,whose low defluorination energy barrier significantly promotes the construction of LiF-rich cathode/electrolyte interface layer on the surface of LCO,thereby eventually suppresses the phase transition and enhancesLi+diffusion kinetics.The rationally designed electrolyte endows graphite||HV-LCO pouch cells with long cycle life(85.3%capacity retention after 700 cycles),wide-temperature adaptability(-60–80℃)and high safety(pass nail penetration).This work provides new insights into the electrolyte screening and rational design to constructing stable interface for high-energy lithium-ion batteries.
文摘Based on the method of discrete phase, the law of droplets’ deposition in the last stage stationary blade of a supercritical 600 MW Steam Turbine is simulated in the first place of this paper by using the Wet-steam model in commercial software FLUENT, where the influence of inlet angle of water droplets of the stationary blades is also considered. Through the calculation, the relationship between the deposition and the diameter of water droplets is revealed. Then, the amount of droplets deposition in the suction and pressure surface is derived. The result is compared with experimental data and it proves that the numerical simulation result obtained in this paper is reasonable. Finally, a formula of the relationship between the diameter of water droplets and the inlet angle is fit, which could be used for approximate calculation in the engineering applications.
