Abstract
The demand for high-performance, affordable, and safe energy storage solutions is growing, driven in part by the incorporation of fluctuating electricity sources like wind turbines and solar cells in the electric grid. Batteries offer such a storage solution in both distributed systems such as households and large-scale industrial systems. The quest for more resource-efficient alternatives to lithium-ion batteries is on its way to meet the increasing demand. Zinc batteries are particularly ecologically friendly due to their use of abundant raw materials and their facile recyclability. High energy densities add to the benefits of this technology. These advantages stem from the use of zinc metal electrodes in combination with effective and affordable aqueous electrolytes. Zinc battery types are distinguished by their cathode materials and electrolytic charge carriers. Zinc-air batteries work with oxygen from air and have the potential to offer the highest energy densities. Zinc-flow batteries could enable large scale battery storage. Zinc-ion batteries are a more recent development which promise large power densities and long cycle lives. In this review, these technologies are discussed in detail. We summarize the development status of each technology, criticize typical deficiencies of current studies, discuss technological challenges, and highlight promising future research directions.