Lithium metal has been considered to be the most promising anode material for the new generation of energy-storage system.However,challenges still stand in protecting lithium metal from spontaneous reactions with elec...Lithium metal has been considered to be the most promising anode material for the new generation of energy-storage system.However,challenges still stand in protecting lithium metal from spontaneous reactions with electrolytes and preventing the dendritic propagation,both of which would lead to undesirable decrease in Coulombic efficiency.Polysulfone(PSf)membrane with high rigidity and free-volume cavities of approximately 0.3 nm was employed to provide a stable interface on the surface of anodic electrode.The isotropic channels were constructed by the interconnected and uniformly distributed free volumes in the polymer matrix,and were expected to be swelled by solvent molecules and anions of lithium salt and to allow Li+ions to pass through onto the electrode surface.As a result,dendrite-free morphology of deposited lithium was observed.The stabilized interface arose from the PSf film was verified by the promoted performances of Cu|Li cells and steady voltage polarization of Li|Li cells.The full cell with PSf coated anode exhibited excellent cyclability(85%capacity retention rate over 400 cycles at 1C)and an outstanding rate capability(117 m Ah g-1 at 5C).The beneficial performances were further verified by the EIS results.This work provides a new strategic idea to settle the dendritic problems of Li metal anodes.展开更多
The development of novel anode materials,with superior rate capability,is of utmost significance for the successful realization of sodium-ion batteries(SIBs).Herein,we present a nanocomposite of Nb_(2)O_(5)and reduced...The development of novel anode materials,with superior rate capability,is of utmost significance for the successful realization of sodium-ion batteries(SIBs).Herein,we present a nanocomposite of Nb_(2)O_(5)and reduced graphene oxide(rGO)by using hydrothermal-assisted microemulsion route.The water-in-oil microemulsion formed nanoreactors,which restrained the particle size of Nb_(2)O_(5)and shortened the diffusion length of ions.Moreover,the rGO network prevented agglomeration of Nb_(2)O_(5)nanoparticles and improved electronic conductivity.Consequently,Nb_(2)O_(5)@rGO nanocomposite is employed as anode material in SIBs,delivering a capacity of 195 mAh/g after 200 charge/discharge cycles at 0.2 A/g.Moreover,owing to conductive rGO network,the Nb_(2)O_(5)@rGO electrode rende red a specific capacity of 76 mAh/g at high current density of 10 A/g and maintained 98 mAh/g after 1000 charge/discharge cycles at 2 A/g.The Nb_(2)O_(5)@rGO electrode material prepared by microemulsion method shows promising possibilities for application of SIBs.展开更多
基金supported by the Opening Project(SKLACPS-C-21)of the State Key Laboratory of Advanced Chemical Power Source,Guizhou Meiling Power Sources Co.Ltd.the Program for Innovative and Entrepreneurial team in Zhuhai(ZH01110405160007PWC)Key Laboratory of Advanced Chemical Power Sources,Guizhou Meiling Power Sources Co.Ltd.,Zunyi 563003,Guizhou,China,for funding the experiments.
文摘Lithium metal has been considered to be the most promising anode material for the new generation of energy-storage system.However,challenges still stand in protecting lithium metal from spontaneous reactions with electrolytes and preventing the dendritic propagation,both of which would lead to undesirable decrease in Coulombic efficiency.Polysulfone(PSf)membrane with high rigidity and free-volume cavities of approximately 0.3 nm was employed to provide a stable interface on the surface of anodic electrode.The isotropic channels were constructed by the interconnected and uniformly distributed free volumes in the polymer matrix,and were expected to be swelled by solvent molecules and anions of lithium salt and to allow Li+ions to pass through onto the electrode surface.As a result,dendrite-free morphology of deposited lithium was observed.The stabilized interface arose from the PSf film was verified by the promoted performances of Cu|Li cells and steady voltage polarization of Li|Li cells.The full cell with PSf coated anode exhibited excellent cyclability(85%capacity retention rate over 400 cycles at 1C)and an outstanding rate capability(117 m Ah g-1 at 5C).The beneficial performances were further verified by the EIS results.This work provides a new strategic idea to settle the dendritic problems of Li metal anodes.
基金supported by the National Natural Science Foundation of China(Nos.21576028 and 21506012)the Opening Project of State Key Laboratory of Advanced Chemical Power Sources(No.SKL-ACPS-C-19)。
文摘The development of novel anode materials,with superior rate capability,is of utmost significance for the successful realization of sodium-ion batteries(SIBs).Herein,we present a nanocomposite of Nb_(2)O_(5)and reduced graphene oxide(rGO)by using hydrothermal-assisted microemulsion route.The water-in-oil microemulsion formed nanoreactors,which restrained the particle size of Nb_(2)O_(5)and shortened the diffusion length of ions.Moreover,the rGO network prevented agglomeration of Nb_(2)O_(5)nanoparticles and improved electronic conductivity.Consequently,Nb_(2)O_(5)@rGO nanocomposite is employed as anode material in SIBs,delivering a capacity of 195 mAh/g after 200 charge/discharge cycles at 0.2 A/g.Moreover,owing to conductive rGO network,the Nb_(2)O_(5)@rGO electrode rende red a specific capacity of 76 mAh/g at high current density of 10 A/g and maintained 98 mAh/g after 1000 charge/discharge cycles at 2 A/g.The Nb_(2)O_(5)@rGO electrode material prepared by microemulsion method shows promising possibilities for application of SIBs.