Biomimetic ant-nest ionogel electrolyte boosts the performance of dendrite-free lithium batteries

Abstract

The use of a rechargeable Li metal anode is one of the most favored choices for next-generation high energy density lithium batteries. Unfortunately, the growth of lithium dendrites during recharging hinders the practical application of Li metal anodes. Herein, we report a new biomimetic ionogel electrolyte with ant-nest architecture by the confinement of an ionic liquid within a chemically modified SiO₂ scaffold for promoting the dendrite-free stripping/plating of Li anodes. The biomimetic ant-nest architecture not only has high ionic conductivity, but can also effectively restrain the Li dendrite growth by the spontaneous formation of a particle-rich protective layer on the lithium electrode during charge/discharge cycling. The solid-state full cells with LiNi_1/3Mn_1/3Co_1/3O₂ exhibit a very high energy density of ca. 390 W h kg⁻¹. The as-prepared Li/Li₄Ti₅O₁₂ full cells present excellent cycling stability up to 3000 cycles with excellent Coulombic efficiencies of >99.8%. The present work opens a new route for the use of the biomimetic concept for designing a new ant-nest ionogel electrolyte for developing high energy density Li metal batteries with high stability.