Tackling realistic Li⁺ flux for high-energy lithium metal batteries.

ABSTRACT: Electrolyte engineering advances Li metal batteries (LMBs) with high Coulombic efficiency (CE) by constructing LiF-rich solid electrolyte interphase (SEI). However, the low conductivity of LiF disturbs Li⁺ diffusion across SEI, thus inducing Li⁺ transfer-driven dendritic deposition. In this work, we establish a mechanistic model to decipher how the SEI affects Li plating in high-fluorine electrolytes. The presented theory depicts a linear correlation between the capacity loss and current density to identify the slope k (determined by Li⁺ mobility of SEI components) as an indicator for describing the homogeneity of Li⁺ flux across SEI, while the intercept dictates the maximum CE that electrolytes can achieve. This model inspires the design of an efficient electrolyte that generates dual-halide SEI to homogenize Li⁺ distribution and Li deposition. The model-driven protocol offers a promising energetic analysis to evaluate the compatibility of electrolytes to Li anode, thus guiding the design of promising electrolytes for LMBs.

SUBMITTER: Zhang S 

PROVIDER: S-EPMC9481556 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature