High Voltage Design for Quasi-Solid Zinc-Air Batteries.

Alkaline zinc-air batteries (ZABs) are recognized as a promising candidate for next generation of safe battery systems, owing to their inherent advantages. However, the performance of traditional ZABs is constrained by a lower theoretical voltage of 1.65 V, presenting a significant challenge in enhancing their practical application. This paper demonstrates a prototype of acid-alkaline hybrid quasi-solid-state zinc-air battery (HSZAB), featuring a unique design in both a new acidic gel electrolyte and battery structure. Our approach involves regulating the electrolyte pH and ionic conductivity to achieve an enhanced theoretical voltage, resulting in an open circuit voltage of up to 2.0 V. Additionally, the HSZAB demonstrates substantially improved peak power density (417 mW cm-2, five times higher than the conventional alkaline ZABs) and increased energy efficiency (from 60% to 82%). This finding underscores the promising prospects of high voltage zinc-air batteries, offering a substantial step forward in the field of energy storage systems.