The inhibited Li dendrite growth via bulk/liquid dual-phase modulation

J Colloid Interface Sci. 2023 Oct 15:648:567-574. doi: 10.1016/j.jcis.2023.05.196. Epub 2023 Jun 3.

Abstract

Li metal is a potential anode material for the next generation high-energy-density batteries because of its high theoretical specific capacity. However, the inhomogeneous lithium dendrite growth restrains corresponding electrochemical performance and brings safety concerns. In this contribution, the Li3Bi/Li2O/LiI fillers are generated by the in-situ reaction between Li and BiOI nanoflakes, which promises corresponding Li anodes (BiOI@Li) showing favorable electrochemical performance. This can be attributed to the bulk/liquid dual modulations: (1) The three-dimensional Bi-based framework in the bulk-phase lowers the local current density and accommodates the volume variation; (2) The LiI dispersed within Li metal is slowly released and dissolved into the electrolyte with the consumption of Li, which will form I-/I3- electron pair and further reactivate the inactive Li species. Specifically, the BiOI@Li//BiOI@Li symmetrical cell shows small overpotential and enhanced cycle stability over 600 h at 1 mA cm-2. Matched with an S-based cathode, the full Li-S battery demonstrates desirable rate performance and cycling stability.

Keywords: Dual regulation effects; I(−)/I(3)(−) electron pair; Li(3)Bi/Li(2)O/LiI fillers; Lithium dendrites; Slow-release effects.