著者

中村 龍哉 松井 裕樹 山田 義博 田渕 光春 小林 陽

出版者

Japan Society of Powder and Powder Metallurgy

雑誌

粉体および粉末冶金 (ISSN:05328799)

巻号頁・発行日

vol.57, no.11, pp.725-728, 2010-11-15

参考文献数

17

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Cathode using the olivine particles was subjected to an open-circuit voltage measurement under the relaxation condition of 24 h at each SOC and DOD states. The electrochemical reaction in the LiFePO<SUB>4</SUB> cathode was composed of a large plateau around 3.45 V with sloped regions nearby for both the fully charged and discharged states. It was found that the potential profile in the sloped regions exhibited a hysteresis. Furthermore, both sloped regions became narrower when the operating temperature was raised from 30 to 60°C. Furthermore, it was found that the apparent diffusion coefficient of Li<SUP>+</SUP> ions in the sloped regions was much smaller than that in the plateau region. These facts implied that the obtained profiles were not in an equilibrium state with a quasi-OCV profile than the real one, and that the potential relaxation in the sloped regions took an extremely long time.