Electrolyte design strategies towards long-term Zn metal anode for rechargeable batteries

Abstract

Rechargeable Zinc (Zn) batteries exhibit great potentials as alternative energy storage devices due to their high safety, low cost, and environmental friendliness. However, the long-standing issues of low Coulombic efficiency (CE) and poor cycle stability of Zn anode, derived from dendrite, H2 evolution, and passivation are directly related to their thermodynamic instability in aqueous electrolyte, severely shorten the battery’s cycle life. Recently reported electrolyte design strategies, which have made great progress to address Zn metal anode problems, are summarized into two categories, that is, aqueous electrolytes about cation-water interaction controlling and interface adjusting, and novel types of electrolytes towards less water, non-aqueous solvents, even no solvents. The final section shows the brief comparisons, including failure mechanisms of electrolyte exhaustion and short circuit for aqueous and non-aqueous electrolyte based full cells respectively, and possible perspectives for future research.