Co@CoO core–shell cross-linked framework modified 3D Cu for dendrite-free lithium anode

Abstract

Lithium metal anode with high energy density is important for developing next-generation batteries. However, low coulombic efficiency, short cycle life, internal short circuits caused by the growth of lithium dendrites, and the high reactivity with the electrolyte have seriously hindered the practical application of lithium metal anode. Herein, we constructed a core–shell cross-link matrix on copper, Co@CoO/3D Cu, for Li metal anode optimization. Various characterizations and DFT simulations jointly reveal the great effects of the special structural features of Co@CoO/3D Cu on enhancing the coulombic efficiency and cyclic stability of Li metal anodes. As a result, the modified half-cell could cycle stably for 240 cycles at 1 mA cm−2 and 1 mA h cm−2 with a coulombic efficiency as high as 98 %. The modified symmetric cell could cycle stably for 1400 h at 1 mA cm−2 and 1 mA h cm−2 with a very low polarization of 22 mV. The modification method proposed in this paper provides a novel path for Li metal anode optimizations.