I₃⁻/I⁻ Redox Reaction‐mediated Organic Zinc‐Air Batteries with Accelerated Kinetics and Long Shelf Lives

Abstract

The storage time of Zn‐air batteries (ZABs) for practical implementation have been neglected long‐lastingly. ZABs based on organic solvents promise long shelf lives but suffer from sluggish kinetics. Here, we report a longly storable ZAB with accelerated kinetics mediated by I3−/I− redox. In the charge process, the electrooxidation of Zn5(OH)8Cl2⋅H2O is accelerated by I3− chemical oxidation. In the discharge process, I− adsorbed on the electrocatalyst changes the energy level of oxygen reduction reaction (ORR). Benefitting from these advantages, the prepared ZAB shows remarkably improved round‐trip efficiency (56.03 % vs. 30.97 % without the mediator), and long‐term cycling time (>2600 h) in ambient air without replacing any components or applying any protective treatment to Zn anode and electrocatalyst. After resting for 30 days without any protection, it can still directly discharge continuously for 32.5 h and charge/discharge very stably for 2200 h (440 cycles), which is evidently superior to aqueous ZABs (only 0/0.25 h, and 50/25 h (10/5 cycles) by mild/alkaline electrolyte replenishment). This study provides a strategy to solve both storage and sluggish kinetics issues that have been plaguing ZABs for centuries, opening up a new avenue to the industrial application of ZABs.

Facet-governed Zn homoepitaxy via lattice potential regulation

“…S55, ESI†). Hence, iodine effectively acts as a mediator in the electrochemical processes, 66,68 facilitating the reversible cycling of Zn. Moreover, the capacity retention rate during shelving is a critical performance metric for a full cell.…”

Electrolyte Tuned Robust Interface toward Fast‐Charging Zn–Air Battery with Atomic Mo Site Catalyst

“…In addition, the binding energy of EG···Zn (−0.091 eV) is higher than that of H 2 O···Zn (−0.055 eV), suggesting the preferential coordination of Zn 2+ to EG rather than H 2 O. [ 33 ] These results prove that the EG participates in the solvation sheath structure of Zn 2+ in RE/EG, resulting in the intensified H‐bonds of EG···H 2 O and the weakened solvation interaction of Zn 2+ with H 2 O. Notably, we also utilize AIMD simulation of RE/EG to obtain a stable electrolyte structure (Figure 1e; Figure S2, Supporting Information).…”

Sustainable zinc–air battery chemistry: advances, challenges and prospects

“…Redox mediators (RMs) are functional materials with electrochemical activities, which play a vital role in altering the reaction pathway and reducing side reactions. 282 RMs can undergo reversible redox reactions in electrochemical cycles. The design of RMs needs to be considered in terms of both functionality and stability.…”