Conversion-type fluoride cathode can provide considerable energy density for Li batteries,however its scalable and facile synthesis strategies are still lacking.Here,a novel Fe-based deep eutectic solvent composed of ...Conversion-type fluoride cathode can provide considerable energy density for Li batteries,however its scalable and facile synthesis strategies are still lacking.Here,a novel Fe-based deep eutectic solvent composed of nitrite and methylsulfonylmethane is proposed as both the reaction medium and precursor to synthesize O-doped FeF3porous bricks.This method is cheaper,safe,mildly operable,environmentally friendly and recyclable for non-fluorinated metal cations.The homogenization of charge and mass transport in cathode network effectively mitigates the volume extrusion and electrode coarsening even for the micro-sized monolithic particles.The Co-solvation modulated fluoride cathode delivers high reversible capacity in a wide temperature range(486 and 235 mA h g^(-1)at 25℃ and-20℃ respectively),excellent rate performance(312 mA h g^(-1)at 1000 mA g^(-1)),corresponding to an energy density as high as672.1 W h kg^(-1)under a power density of 2154.3 W kg^(-1).The successful operation of fluoride pouchcell with a capacity exceeding 450 mA h g^(-1)(even under thin Li foil and lean electrolyte conditions) indicates its potentiality of commercial application.展开更多
The numerical model for predicting the flow and temperature fields of the melt in holding furnace with porous brick purging system were set up using Euler-Lagrange approach.In this model,bubbles coalescence and disint...The numerical model for predicting the flow and temperature fields of the melt in holding furnace with porous brick purging system were set up using Euler-Lagrange approach.In this model,bubbles coalescence and disintegration were ignored based on the dimensionless analysis,and the bubble size was assumed to be obedient to Rosin-Rammler distribution with a mean size of 0.6 mm.The results show that on reference operating condition,during the heating and agitation process,melt mixes well in the furnace,and the melt velocity increases with the increase of gas flux.Holding the melt for 30 min causes the max temperature in the bulk melt to increase to 60 K.After holding the heat,the agitation processing restarts,and it takes 10 min for the stratified melt to retrieve the homogeneous temperature field when the gas flux is 10 L/min,which shows deficient alloying and degassing in the melt.With the increase of gas flux from 10 to 20,30 and 40 L/min,the necessary recovery time decreases from 10 to 6,5 and 4 min gradually,which shows the improvement of the stirring efficiency.Depending on the processing purposes,for both good degassing performance and gas saving,proper operating strategy and parameters (gas flux,primarily) could be adjusted.展开更多
基金supported by the National Natural Science Foundation of China(51772313,21975276 and 52102329)the Shanghai Science and Technology Committee(20520710800)support by the Program of Shanghai Academic Research Leader(21XD1424400)。
文摘Conversion-type fluoride cathode can provide considerable energy density for Li batteries,however its scalable and facile synthesis strategies are still lacking.Here,a novel Fe-based deep eutectic solvent composed of nitrite and methylsulfonylmethane is proposed as both the reaction medium and precursor to synthesize O-doped FeF3porous bricks.This method is cheaper,safe,mildly operable,environmentally friendly and recyclable for non-fluorinated metal cations.The homogenization of charge and mass transport in cathode network effectively mitigates the volume extrusion and electrode coarsening even for the micro-sized monolithic particles.The Co-solvation modulated fluoride cathode delivers high reversible capacity in a wide temperature range(486 and 235 mA h g^(-1)at 25℃ and-20℃ respectively),excellent rate performance(312 mA h g^(-1)at 1000 mA g^(-1)),corresponding to an energy density as high as672.1 W h kg^(-1)under a power density of 2154.3 W kg^(-1).The successful operation of fluoride pouchcell with a capacity exceeding 450 mA h g^(-1)(even under thin Li foil and lean electrolyte conditions) indicates its potentiality of commercial application.
基金Project(2008AA11A116) supported by the National High Technology Research and Development Program of China
文摘The numerical model for predicting the flow and temperature fields of the melt in holding furnace with porous brick purging system were set up using Euler-Lagrange approach.In this model,bubbles coalescence and disintegration were ignored based on the dimensionless analysis,and the bubble size was assumed to be obedient to Rosin-Rammler distribution with a mean size of 0.6 mm.The results show that on reference operating condition,during the heating and agitation process,melt mixes well in the furnace,and the melt velocity increases with the increase of gas flux.Holding the melt for 30 min causes the max temperature in the bulk melt to increase to 60 K.After holding the heat,the agitation processing restarts,and it takes 10 min for the stratified melt to retrieve the homogeneous temperature field when the gas flux is 10 L/min,which shows deficient alloying and degassing in the melt.With the increase of gas flux from 10 to 20,30 and 40 L/min,the necessary recovery time decreases from 10 to 6,5 and 4 min gradually,which shows the improvement of the stirring efficiency.Depending on the processing purposes,for both good degassing performance and gas saving,proper operating strategy and parameters (gas flux,primarily) could be adjusted.
