Controlled Morphology Direct Iron Reduction from an Alkaline Slurry of Hematite for a Low-Cost Energy Storage Technology

Abstract

Iron-air batteries became a promising research direction for low-cost and long-duration energy storage. Moreover, extensive work on iron-related technologies can assist in the decarbonization of the steelmaking industry.1 To mitigate the issue of a parasitic hydrogen evolution reaction that significantly lowers the high theoretical specific capacity of the device, grafted Fe/C, as well as carbonyl-iron composite electrodes were studied.2 Despite the effectiveness of such methods and commercialization success, the complicated nature of a starting material makes it costly for plant-scale production. In this work, we are presenting the iron-plating method under alkaline conditions which is aimed to produce various morphology anodes for improved cycling in a pouch-cell with a perspective usage in the iron-air storage technology. This preparation approach of the battery component from abundant metal could replace the more emission-intensive technologies being used today. Additionally, a study on zinc monolithic anodes has proven to dramatically elevate the performance of the primary and secondary devices predicting a similar success for various metals.3 In the first cycle of the research, we discover how the faradaic efficiency and specific capacity of direct iron metal deposition from the iron (III) oxide slurry are impacted by varying temperatures of the process. Additionally, changes in the morphology and the porosity distribution are observed based on the initial controlled hematite particle size. The second cycle is dedicated to the cycling behavior of the prepared anodes. By performing a set of characterizations, we are able to account for the factors influencing the final performance of the prepared anodes. These findings allow us to better understand the feasibility of such a preparation method of the iron anode for an alternative energy storage scale-up. Woodford, W. H.; Burger, S.; Ferrara, M.; Chiang, Y.-M., The iron-energy nexus: A new paradigm for long-duration energy storage at scale and clean steelmaking. One Earth 2022, 5 (3), 212-215.Hang, B. T.; Eashira, M.; Watanabe, I.; Okada, S.; Yamaki, J.-I.; Yoon, S.-H.; Mochida, I., The effect of carbon species on the properties of Fe/C composite for metal–air battery anode. Journal of Power Sources 2005, 143 (1-2), 256-264.Joseph F. Parker, C. N. C., Irina R. Pala, Meinrad Machler, Michael F. Burz, Jeffrey W. Long, Debra R. Rolison, Rechargeable nickel–3D zinc batteries: An energy-dense, safer alternative to lithium-ion. Science 2017, 356, 415–418.