The solid electrolyte interface(SEI)layer plays a crucial role in the cycling process of lithium(Li)metal batteries,especially in the process of Li stripping and plating at high current densities.However,the naturally...The solid electrolyte interface(SEI)layer plays a crucial role in the cycling process of lithium(Li)metal batteries,especially in the process of Li stripping and plating at high current densities.However,the naturally formed SEI is too fragile to prevent the uncontrolled growth of lithium dendrites.In this work,we report the growth of a magnesium fluoride(MgF_(2))-rich artificial SEI for Li metal anodes.The dense MgF_(2)-rich SEI layer can homogenize lithium ion(Li^(+))flux to effectively inhibit the growth of lithium dendrites and reduce the overpotential of Li^(+)nucleation,thus effectively regulating the behavior of Li-plating/Li-stripping.Due to the good mechanical properties of the dense MgF_(2)-rich SEI layer,the Li||Li@MgF_(2)symmetric cell exhibits an overpotential of less than 40 mV(at 3 mA cm^(−2)and 1 mA h cm^(−2)for 800 h).The LiFePO_(4)||Li@MgF_(2)full cell provides a capacity of around 89.2 mA h g^(−1)with a capacity retention rate of 70.23%even after 1000 cycles at 2C.This synthesis of a stable SEI layer opens up new prospects for the next generation of highly stable Li metal batteries.展开更多
基金supported by the National Key R&D Program of China(2021YFE0115800)National Natural Science Foundation of China(22275142,22293022,U22B6011,U20A20122,52103285)+1 种基金Science Technology&Innovation Funding Authority(STDF)under grant(47280)Program of Introducing Talents of Discipline to Universities-Plan 111 from the Ministry of Science and Technology and the Ministry of Education of China(B20002).
文摘The solid electrolyte interface(SEI)layer plays a crucial role in the cycling process of lithium(Li)metal batteries,especially in the process of Li stripping and plating at high current densities.However,the naturally formed SEI is too fragile to prevent the uncontrolled growth of lithium dendrites.In this work,we report the growth of a magnesium fluoride(MgF_(2))-rich artificial SEI for Li metal anodes.The dense MgF_(2)-rich SEI layer can homogenize lithium ion(Li^(+))flux to effectively inhibit the growth of lithium dendrites and reduce the overpotential of Li^(+)nucleation,thus effectively regulating the behavior of Li-plating/Li-stripping.Due to the good mechanical properties of the dense MgF_(2)-rich SEI layer,the Li||Li@MgF_(2)symmetric cell exhibits an overpotential of less than 40 mV(at 3 mA cm^(−2)and 1 mA h cm^(−2)for 800 h).The LiFePO_(4)||Li@MgF_(2)full cell provides a capacity of around 89.2 mA h g^(−1)with a capacity retention rate of 70.23%even after 1000 cycles at 2C.This synthesis of a stable SEI layer opens up new prospects for the next generation of highly stable Li metal batteries.
