High-Rate Cycling of Lithium-Metal Batteries Enabled by Dual-Salt Electrolyte-Assisted Micropatterned Interfaces

Abstract

We present a synergistic strategy to boost the cycling performance of Li-metal batteries. The strategy is based on the combined use of a micropattern (MP) on the surface of the Limetal electrode and an advanced dual-salt electrolyte (DSE) system to more efficiently control undesired Li-metal deposition at higher current density (similar to 3 mA cm(-2)). The MP-Li electrode induces a spatially uniform current distribution to achieve dendrite-free Li-metal deposition beneath the surface layer formed by the DSE. The MP-Li/DSE combination exhibited excellent synergistic rate capability improvements that were neither observed with the MP-Li system nor for the bare Li/DSE system. The combination also resulted in the LillLiMn(2)O(4) battery attaining over 1000 cycles, which is twice as long at the same capacity retention (80%) compared with the control cells (MP-Li without DSE). We further demonstrated extremely fast charging at a rate of 15 C (19.5 mA cm(-2)).