Nanobead-reinforced solid-electrolyte interphase layers for suppressing dendrite formation on lithium metal anodes

Abstract

Lithium metal is the most attractive anodes for lithium ion batteries due to its ultrahigh capacity (3860 mAh g-1) and low density (0.59 g cm-3). However, the lithium metal anodes suffer from dendrite formation causing low coulombic efficiency and short-circuiting cells. To suppress the dendrite formation, in this work, inorganic nanobeads were introduced into liquid electrolytes of lithium metal cells. Interestingly, the simple oxide additive strategy decreased impedance, improved dendrite morphology and prolonged cycle life of symmetric Li0||Li0 cells. Three reasons for the improvement were feasible: (1) surface charge of nanoparticles encourages desolvation of solvated lithium ions just before deposition; (2) moisture content adsorbed on nanoparticle surface promotes LiPF6 decomposition to form F-rich solid electrolyte interphase (SEI) layers; and (3) the nanobeads reinforced the SEI layers in terms of mechanical strength.