Long-Life Aqueous Zinc–Organic Batteries with a Trimethyl Phosphate Electrolyte and Organic Cathode

Abstract

Aqueous zinc batteries (AZBs) are environment-friendly batteries with good application prospects. However, their applications are plagued by the dendrite growth of Zn anodes and the absence of suitable cathodes. Herein, we design and realize high-performance AZBs by using an organic cathode of 5,7,12,14-pentacenetetrone (PT) and a trimethyl phosphate (TMP)/water hybrid electrolyte. The COMSOL simulations and spectroscopy studies collectively demonstrate a strong interaction between TMP and Zn2+, thus changing the solvation structure and suppressing the parasitic reactions, finally enabling dendrite-free Zn plating/stripping. The hybrid electrolyte shows good compatibility with the PT cathode. As a consequence, the Zn//PT full cell employing the hybrid electrolyte exhibits remarkable capacity (229.4 mA h g–1 at 0.1 A g–1), extraordinary rate performance, and long-term cycling (84.18% retention after 9600 cycles) at a wide temperature range (−20 to 65 °C).