The Current State of Aqueous Zn-Based Rechargeable Batteries

Zn-based electrochemistry has recently been considered as the most promising family to challenge the dominant status of Li-based battery technologies. Besides its more abundant reserves, the moderate reactivity and aqueous electrolyte compatibility of Zn result in higher safety and lower cost. More importantly, the involved two-electron redox of Zn2+/Zn couples can provide higher theoretical capacity and energy density. On the basis of Zn electrochemistry, a series of battery technologies, including Zn-ion, Zn-air, and Zn-based redox flow batteries as well as their hybrid and flexible derivatives, have been developed and attracted increasing research enthusiasm. Herein, the basic principles and latest advances of aqueous Zn-based rechargeable batteries are presented as the basis of current research, along with perspectives for the direction of further investigations.