Disrupting Zn2+−H2O Coordination and Constructing Zn2+-Enriched Interface for Low-Polarization Aqueous Zinc Slurry Batteries

ABSTACT:

Aqueous zinc-powder slurry batteries hold significant promise for large-scale energy storage owing to their simple manufacturing, design flexibility, and high reactivity. However, their high water content and the reactive nature of zinc powder exacerbate parasitic side reactions and sluggish Zn2+ migration kinetics. Therefore, 3-mercapto-1-propanesulfonate is incorporated into a polyacrylamide-based slurry. The zincophilic additive can disrupt the strong Zn2+−H2O coordination and preferentially adsorb onto zinc powder surfaces, constructing a Zn2+-enriched interface that facilitates ion transport and reduces polarization. As a result, the Zn||Zn symmetric cell delivers an ultralong cycling stability exceeding 1200 h, and the NH4V4O10 full cell maintains a high capacity retention of 80% after 1000 cycles at 4 A g−1. This work offers a coordination-chemistry-guided strategy for designing aqueous zinc slurry anodes with enhanced stability and reversibility.