Dendrite-free and stable zinc-ion batteries enabled by a cation-anion synergistic regulation additive

Abstract

Dendrite growth and parasitic reactions in Zn anodes limit the implementation of aqueous zinc ion batteries (AZIBs). Here, tetraethyl ammonium chloride (TEAC) is proposed as an effective, nontoxic and bi-functional electrolyte additive during the Zn plating/striping to suppress the growth of dendrite and by-products in AZIBs. Benefiting from its inherent surfactant properties, the preferential adsorption of cations TEA+ on the Zn anode surface facilitates the uniform Zn deposition and restrains the dendrite growth, while the anions Cl− promote the ions transport and reduce the battery polarization. The synergistic regulation of cation and anion enable the Zn||Zn symmetric cells outstanding cycling stability over 2450 h and 1600 h at 1 mA cm−2 and 5 mA cm−2, respectively. Additionally, Zn||MnO2 full cells exhibit high-capacity retention of 88% after 2000 cycles at 3 A g−1. This work provides a promising approach of synergistic regulation with cation and anion of electrolyte additives to promote the stability of Zn anode for high-performance AZIBs batteries.