TY - JOUR
T1 - Energy efficiency of neptunium redox battery in comparison with vanadium battery
AU - Yamamura, T.
AU - Watanabe, N.
AU - Shiokawa, Y.
N1 - Funding Information:
We would like to thank Prof. Hajimu Yamana of Kyoto University, Dr. Zenko Yoshida and Dr. Toru Ogawa of Japan Atomic Energy Research Institute, Dr. Ken Nozaki of National Institute of Advanced Industrial Science and Technology for helpful discussion and encouragement. The authors thank the Asahi Kasei Corporation, Japan, for providing ion exchange membranes used in the present study. This work was performed at the Irradiation Experimental Facility, Institute for Materials Research (IMR), Tohoku University, and under the cooperative research program of IMR, Tohoku University. This work is supported by the Nuclear Research Promotion Program (JANP) of the Japan Atomic Energy Research Institute and a Grant-in-Aid for Scientific Research from The Ministry of Education, Culture, Sports, Science and Technology.
PY - 2006/2/9
Y1 - 2006/2/9
N2 - A neptunium ion possesses two isostructural and reversible redox couples (Np3+/Np4+ and NpO2+/NpO 22+) and is therefore suitable as an active material for a redox-flow battery. Since the plastic formed carbon (PFC) is known to show the largest k0 values for Np(IV)/Np(III) and Np(V)/Np(VI) reactions among various carbon electrodes, a cell was constructed by using the PFC, with the circulation induced by bubbling gas through the electrolyte. In discharge experiments with a neptunium and a vanadium battery using the cell, the former showed a lower voltage loss which suggests a smaller reaction overvoltage. Because of the high radioactivity of the neptunium, it was difficult to obtain sufficient circulation required for the redox-flow battery, therefore a model for evaluating the energy efficiency of the redox-flow battery was developed. By using the known k0 values for neptunium and vanadium electrode reactions at PFC electrodes, the energy efficiency of the neptunium battery was calculated to be 99.1% at 70 mA cm-2, which exceeds that of the vanadium battery by ca. 16%.
AB - A neptunium ion possesses two isostructural and reversible redox couples (Np3+/Np4+ and NpO2+/NpO 22+) and is therefore suitable as an active material for a redox-flow battery. Since the plastic formed carbon (PFC) is known to show the largest k0 values for Np(IV)/Np(III) and Np(V)/Np(VI) reactions among various carbon electrodes, a cell was constructed by using the PFC, with the circulation induced by bubbling gas through the electrolyte. In discharge experiments with a neptunium and a vanadium battery using the cell, the former showed a lower voltage loss which suggests a smaller reaction overvoltage. Because of the high radioactivity of the neptunium, it was difficult to obtain sufficient circulation required for the redox-flow battery, therefore a model for evaluating the energy efficiency of the redox-flow battery was developed. By using the known k0 values for neptunium and vanadium electrode reactions at PFC electrodes, the energy efficiency of the neptunium battery was calculated to be 99.1% at 70 mA cm-2, which exceeds that of the vanadium battery by ca. 16%.
KW - Energy efficiency
KW - Neptunium battery
KW - Redox-flow battery
KW - Vanadium battery
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U2 - 10.1016/j.jallcom.2005.04.174
DO - 10.1016/j.jallcom.2005.04.174
M3 - Conference article
AN - SCOPUS:31144441656
VL - 408-412
SP - 1260
EP - 1266
JO - Journal of Alloys and Compounds
JF - Journal of Alloys and Compounds
SN - 0925-8388
T2 - Proceedings of the Rare Earths'04 in Nara, Japan
Y2 - 7 November 2004 through 12 November 2004
ER -
