Abstract
-
Li metal is the most ideal anode material for next-generation high energy lithium-ion batteries. The uncontrollable growth of Li dendrites, however, hinders its practical application. Herein, we propose the adoption of Zn nanoparticles uniformly embedded in N-doped carbon polyhedra homogeneously built on carbon cloth (Zn@NC@CC) to prevent the formation of Li dendrites. Based on theoretical calculation and experimental observation, lithiophilic Zn nanoparticles and N-doping inside of the as-synthesized Zn@NC play a synergistic role in enhancing the adsorption capacity with Li, thus resulting in uniform Li deposition and complete suppression of Li dendrites. Moreover, the porous N-doped carbon polyhedras uniformly distributed on carbon cloth effectively relieves the volume change of Li upon repeated Li stripping/plating process, which contributes to preserving the structural integrity of the whole electrode and hence enhancing its long-term cycling stability. Benefiting from these synergistic effects, the Li-Zn@NC@CC electrode delivers a prolonged lifespan of over 1200 h at 1 mA cm−2 with an areal capacity of 1 mA h cm−2 in symmetric cells and high Coulombic efficiencies of 95.4% under an ultrahigh capacity of 12 mA h cm−2. Remarkably, Li-Zn@NC@CC//LiFePO4 full cells deliver a high reversible capacity of 110.2 mA h g−1 at 1C over 200 cycles.