Co-guiding the dendrite-free plating of lithium on lithiophilic ZnO and fluoride modified 3D porous copper for stable Li metal anode

Abstract

Lithium metal battery is considered to be the most promising energy storage technologies due to its ultra-high theoretical capacity and extremely low standard potential. However, the infinite volume change during uneven deposition/dissolution process and the growth of lithium dendrite resulting in severe capacity decay and high safety hazards, which hinders the application in next generation secondary batteries. In this paper, the three dimensional (3D) porous copper is prepared through an electrochemical etching CuZn alloy, and the pore walls are modified with lithiophilic layer of ZnO and fluorine. The as-prepared 3D Cu/ZnO/F can inhibit the growth of Li dendrite and mitigate the huge volume change of Li metal anode during cycling process, resulting in stable solid electrolyte interface (SEI) layer and electrode structure. The Li|3D Cu/ZnO/F cell can be stably cycled over 300 cycles with 98% of coulomb efficiency at 0.5 mA cm−2, 1 mAh cm−2. The synergistic effects of both ZnO and fluorine on inducing the uniform deposition of lithium by providing bonding sites can inhibit the generation of lithium dendrites and thus improve the electrochemical performance of lithium metal batteries. Keywords: Lithium metal battery, 3D copper, Lithium dendrites, Modification