Post-hoc comparisons among iron electrode formulations based on bismuth, bismuth sulphide, iron sulphide, and potassium sulphide under strong alkaline conditions

• Published in: Journal of power sources Vol. 268; pp. 810 - 815
• Main Authors: Gil Posada, Jorge Omar, Hall, Peter J.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 05.12.2014; Elsevier
• Subjects: Applied sciences; Bismuth; Coulombic efficiency; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Electrodes; Exact sciences and technology; Intermetallics; Iron; Iron compounds; Iron electrode; Nickel base alloys; Nickel compounds; NiFe cell; Post-hoc comparison; Sulfides; Coulombic efficiency; Iron electrode; NiFe cell; Post-hoc comparison; Secondary cell; Transition metal; Iron; Iron nickel batteries; Electrodes; Potassium Sulfides; Formulation; Bismuth; Current efficiency; Comparative study
• DOI: 10.1016/j.jpowsour.2014.06.126
• ISSN: 0378-7753

Iron electrodes were prepared by hot-pressing iron-polyethylene based formulations on nickel foam stripes. NiFe cells were tested by using commercial nickel electrodes and our iron electrodes. Post-hoc comparisons were used to identify meaningful differences between iron electrode formulations (based upon bismuth, bismuth sulphate, potassium sulphide and iron sulphide as additives). Our results confirm that both bismuth sulphide and iron sulphide favour the process of charge/discharge of a NiFe cell. In addition, we have found that the use of metallic bismuth only marginally influences coulombic efficiency; likewise, the presence of the soluble bisulfide anion is not sufficient to increase coulombic efficiency. Finally, NiFe cells prepared with bismuth sulphide outperformed their iron sulphide counterparts. [Display omitted] •We investigate sulphur containing additives in the performance of NiFe cells.•We perform post-hoc comparisons among NiFe cell formulations.•The performance of a NiFe cell depends on the initial cycles of charge/discharge.