Transforming Zinc-Ion Batteries with DTPA-Na: A Synergistic SEI and CEI Engineering Approach for Exceptional Cycling Stability and Self-Discharge Inhibition.

ABSTRACT

Aqueous zinc-ion batteries (ZIBs) hold immense promise for large-scale energy storage, but their practical application is hindered by zinc anode limitations. We introduce diethylenetriamine pentaacetate sodium salt (DTPA-Na) as a novel electrolyte additive to address these challenges. DTPA-Na's unique dual functionality enables the formation of robust, multi-layered solid electrolyte interphases (SEI) on the zinc anode and stable cathode electrolyte interphases (CEI) on the MnOOH cathode. This synergistic SEI/CEI engineering approach effectively suppresses interfacial side reactions, promotes uniform zinc deposition, and inhibits dendrite growth, leading to exceptional cycling stability and self-discharge inhibition. Asymmetrical cells employing DTPA-Na achieve an unprecedented 32,000 cycles at a high charging rate of 50 mA/cm2, while symmetric cells demonstrate a lifespan of 160 hours with 95% zinc utilization. Full Zn||MnOOH cells exhibit remarkable stability, maintaining 98.61% capacity retention after 720 hours of self-discharge and negligible capacity decay over 5000 cycles. Our work highlights the transformative potential of DTPA-Na as a dual-functional electrolyte additive, paving the way for high-performance ZIBs for practical energy storage applications.