Recent Progress In Extending The Cycle-Life Of Secondary Zn-Air Batteries

Secondary Zn-air batteries with stable voltage and long cycle-life are of immediate interest to meet global energy storage needs at various scales. Although primary Zn-air batteries have been widely used since the early 1930s, large-scale development of electrically rechargeable variants has not been fully realized due to their short cycle-life. In this work, we review some of the most recent and effective strategies to extend the cycle-life of Zn-air batteries. Firstly, diverse degradation routes in Zn-air batteries will be discussed, linking commonly observed failure modes with the possible mechanisms and root causes. Next, we evaluate the most recent and effective strategies aimed at tackling individual or multiple of these degradation routes. Both aspects of cell architecture design and materials engineering of the electrodes and the electrolytes will be thoroughly covered. Finally, we offer our perspective on how the cycle-life of Zn-air batteries can be extended with concerted and tailored research directions to pave the way for their use as the most promising secondary battery system of the future.