Pyrophosphate Na2FeP2O7 as a low-cost and high-performance positive electrode material for sodium secondary batteries utilizing an inorganic ionic liquid

JOURNAL OF POWER SOURCES

卷:246

Article

Chen, Chih-Yao¹  Matsumoto, Kazuhiko¹  Nohira, Toshiyuki¹  Hagiwara, Rika¹  Orikasa, Yuki²  Uchimoto, Yoshiharu² 

[1] Kyoto Univ, Grad Sch Energy Sci, Sakyo Ku, Kyoto 6068501, Japan

[2] Kyoto Univ, Grad Sch Human & Environm Studies, Sakyo Ku, Kyoto 6068501, Japan

关键词: Sodium secondary battery;    Na2FeP2O7;    Positive electrode;    Ionic liquid;    Bis(fluorosulfonyl)amide;   

DOI  :  10.1016/j.jpowsour.2013.08.027

来源: Elsevier

【 摘 要 】

The electrochemical performance of a Na2FeP2O7 positive electrode has been evaluated in an inorganic ionic liquid NaFSA-KFSA (FSA = bis(fluorosulfonyl)amide) at 363 K. The electrode delivers a reversible capacity of 91 mAh g(-1) with excellent rate capability (59 mAh g(-1) at 2000 mA g(-1)) and a capacity retention of 91% over 1000 cycles, which facilitates the development of low-cost and high-safety sodium secondary batteries for large-scale energy storage applications. The average oxidation state of iron increases upon sodium extraction, as evidenced by the edge shift of an X-ray absorption spectroscopy analysis. According to an extended X-ray absorption fine structure analysis, the sodium extraction is accompanied by a shortening of Fe-O bonds. (C) 2013 Elsevier B.V. All rights reserved.

【 授权许可】

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