Advancements in Zinc Sponge Anode Fabrication for Scale-up, Manufacture and Battery Performance

Zinc (Zn) anodes were historically prone to shape change, short-inducing dendrite formation, and suboptimal redox utilization in aqueous battery systems, particularly when subjected to extensive charge–discharge cycling. The Naval Research Laboratory introduced a 3D-architected Zn “sponge” design that mitigates many of the historic limitations of Zn anodes [1]. Over several years of development, the fabrication routes to Zn sponges have continued to evolve from early proof-of-concept examples with specialized chemicals and multistage thermal processing toward a more recent focus on methods that are fast, low-cost, readily scalable, and energy efficient. The latest protocols use simple inorganic porogens such as sodium chloride and potassium carbonate in conjunction with chemical sintering and simplified heating steps to produce robust Zn sponges in varied monolithic forms (discs, plates, cylinders) and scales (up to 20 cm on a side). We will discuss the latest advances in the fabrication, materials characterization, and electrochemical evaluation of Zn sponges as directed toward their use as anodes in aqueous batteries (alkaline to mild-pH).<br/><br/>1. J. F. Parker, C. N. Chervin, E. S. Nelson, D. R. Rolison, and J.W. Long. <i>Energy Environ. Sci.</i> 7 (2014) 1117–1124.