High-Entropy-Inspired Multicomponent Electrical Double Layer Structure Design for Stable Zinc Metal Anodes.

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Electrical double layer (EDL) engineering is crucial for enhancing zinc metal anode cycling stability.
• The efficacy of single additives in modifying EDL structure is often limited.
• High-entropy (HE) concepts offer a new paradigm for designing multicomponent systems.

Purpose of the Study:

• To develop a multicomponent (MC) EDL structure for improved zinc anode performance.
• To investigate the synergistic effects of La3+, Cl-, and BBI anions in the EDL.
• To introduce a novel synergistic parameter for quantifying additive collaboration.

Main Methods:

• Formulation of a novel electrolyte: dibenzenesulfonimide (BBI) and LaCl3 additives in ZnSO4 electrolyte (BBI/LaCl3/ZnSO4).
• Characterization of the MC EDL structure and its influence on Zn surface.
• Electrochemical testing of Zn anodes and Zn|MnO2 pouch cells.

Main Results:

• The MC EDL, featuring La3+ shielding and co-adsorbed BBI/Cl- anions, promotes uniform electric fields, robust solid electrolyte interphase (SEI) layers, and balanced reaction kinetics.
• A synergistic parameter was proposed and validated, quantifying the combined benefits of BBI and LaCl3.
• Zinc anodes demonstrated high reversibility (99.5%) at 51.3% depth of discharge (DoD).
• Zn|MnO2 pouch cells achieved 100 cycles with stable performance at a low N/P ratio of 2.9.

Conclusions:

• The developed MC EDL strategy effectively regulates zinc anode behavior, overcoming limitations of single additives.
• The synergistic interaction between additives is key to achieving enhanced electrochemical performance.
• This approach offers a promising pathway for developing high-performance and stable zinc-based batteries.