A Transformative-Type Additive Cu–EDTA toward Ultrastable Aqueous Zn Anodes

Aqueous zinc-ion batteries (AZIBs) hold great promise for sustainable energy storage, yet their practical viability is constrained by Zn dendrites and water-induced parasitic reactions. However, conventional additives generally address only one of these issues and lack dynamic interfacial regulation, failing to achieve the long-term stability of the Zn anode. Herein, we introduce a transformative-type additive Cu–EDTA that dynamically evolves into two functional cooperative species: a CuZn5 alloy and Zn–EDTA adsorbates. The electrochemically formed CuZn5 alloy induces the growth of the Zn(101) texture, thus suppressing Zn dendrites. The spontaneously formed Zn–EDTA adsorbates construct a poor water, which can effectively exclude H2O from the electrode/electrolyte interface, preventing the adverse water–parasitic reactions. In the Zn//Zn symmetrical batteries, the Cu–EDTA additive realizes an ultralong cycling stability over 10,000 h at 2 mA cm–2/1 mAh cm–2. An ultrahigh reversibility with an average Coulombic efficiency of 99.96% is achieved in the Zn//Cu asymmetrical battery. The Zn//MnO2 cell retains stable operation over 10,000 cycles at 5 A g–1. This work gives a simple transformative additive paradigm for the comprehensive solution of stabilizing the Zn anodes in the practical development of AZIBs.