Toward Stable Lithium Plating/Stripping by Successive Desolvation and Exclusive Transport of Li Ions

摘要

Li has been regarded as the most attractive anode for next-generation high-energy-density batteries due to its high specific capacity and low electrochemical potential. However, its low electrochemical potential leads to the side reaction of Li with the solvent of the electrolyte (the solvation of Li ions exacerbates the reaction). This adverse side reaction results in uneven Li distribution and deposition, low Coulombic efficiency, and the formation of Li dendrites. Herein, we demonstrate an efficient method for achieving successive desolvation and homogeneous distribution of Li ions by using a double-layer membrane. The first layer is designed to enable the desolvation of Li ions. The second layer with controllable and ordered nanopores is expected to facilitate the homogeneous and exclusive transport of Li ions. The efficiency of the double-layer membrane on desolvation and exclusive transport of Li ions is confirmed by theoretical calculations, the significantly enhanced Li-ion transference number, improved Coulombic efficiency, and the inhibition of Li dendrites. These results will deepen our understanding of the modulation of ions and pave a way to the next-generation high-energy-density Li-metal batteries.