Effect of Ti(IV) Ion on Mn(III) Stability in Ti/Mn Electrolyte for Redox Flow Battery. (27th July 2016)

• Record Type: Journal Article
• Authors: Kaku, Hirokazu; Dong, Yong-Rong; Hanafusa, Kei; Moriuchi, Kiyoaki; Shigematsu, Toshio
• Is Part Of: ECS transactions. Volume 72:Number 10(2016)
• Page Start: 1
• Page End: 9
• Publication Date: 2016-07-27
• Subjects: Electrochemistry -- Periodicals; Electrochemistry; Periodicals; Electronic journals; Electronic journal; 541.37
• DOI: 10.1149/07210.0001ecst
• Languages: English
• ISSNs: 1938-5862

Abstract

Abstract : The mixed electrolyte of titanium and manganese is one of the promising candidates as low-cost electrolytes for redox flow batteries. In this study, the effect of Ti 4+ ion in the positive electrolyte was examined in detail. With an increase of Ti 4+ ion concentration, the formation reaction of MnO2 particle was slowed down significantly, which means the stability of Mn 3+ ion is enhanced. Moreover, the particle size of MnO2 precipitate became smaller in electrolytes containing certain amount of Ti 4+ ion. These MnO2 particles were small enough to be flowed in the electrolyte and to be reduced to Mn 2+ ion again. Ti 4+ ion also affected the crystal structures of MnO2, limiting to gamma-MnO2 which is assumed to be reactive. In cyclic voltammetry study, the higher Ti 4+ ion concentration was, the better reversibility of Mn redox reaction was observed. The ion interaction between Ti 4+ and Mn 3+ was confirmed by UV-visible spectroscopy.