摘要
Lithium(Li) metal is considered as the most promising anode material for the next-generation high performance Li batteries.However,the uncontrollable dendritic growth impedes its commercial application.Herein,we design a 3 D Si@carbon nanofibers(CNFs)@ZnO-ZnO-Cu skeleton(SCZ) for guiding the homogeneous bottom-growth of Li metal.The top LixSi@CNFs and bottom LiyZn@CNFs layers could form conductivity and overpotential gradient to avoid the "top-growth" of Li metal.Moreover,the top lithiophilic LixSi@CNFs layer could regulate the nucleation and deposition of Li-ions even if the lithium dendrites grow out of the skeleton under high capacity Li deposition(30 mAh cm^(-2)).As a result,the SCZ-Li||LiFePO_(4) full cell delivers a high capacity of ~104 mAh g^(-1)(~94.82% capacity retention) after 2000 cycles at 5 C, elucidating the potential application of the 3 D double-gradient Li metal composite anode.
基金
financial support from the National Natural Science Foundation of China(Grant Nos.51701169,51871188 and 51931006)
the National Key R&D Program of China(Grant No.2016YFA0202602)
the Natural Science Foundation of Fujian Province of China(No.2019J06003)
the "Double-First Class" Foundation of Materials and Intelligent Manufacturing Discipline of Xiamen University。