posted on 2022-07-14, 18:08authored byGeng Luo, Xiaoguang Yin, Dongqing Liu, Arshad Hussain, Fude Liu, Xingke Cai
Three dimensional (3D) hosts have been recognized as
effective
current collectors for Li metal anodes because of their physical suppression
of the lithium dendrites growth. A lithiophilic surface layer on them
could increase the Li metal nucleation sites, further regulating the
genuine plating of Li metal. The current strategies to construct this
lithiophilic layer on 3D structure is complex and not suitable for
the scalable fabrication of Li metal anode. In this work, we developed
a facile method to grow vertically aligned ZnO nanoflakes on the surface
of 3D Cu foam through an electrochemical synthetic process, which
physically suppressed the Li dendrites growth due to the unique structure
during the Li plating/stripping process. Moreover, these lithiophilic
flakes effectively increase the specific surface area of the anode
and Li metal nucleation sites number, which reduces the local current
densities, leading to the formation of a robust SEI and further suppressing
the Li dendrites growth. Consequently, the performances of the symmetric
Li plated Cu foam/Li cell and the Li plated Cu foam/LiFePO4 full cell have been greatly enhanced after the growth of vertically
aligned ZnO nanoflakes on the Cu foam surface, including capacity,
cycling stability, overpotential, and rate capability.