著者

Nakamura Eiji He Ping Deguchi Kiyoshi

出版者

一般社団法人日本物理学会

雑誌

J Phys Soc Jpn (ISSN:00319015)

巻号頁・発行日

vol.60, no.9, pp.2839-2842, 1991-09-15

被引用文献数

2

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The onset temperature $T_{\text{m}}$ and the Vogel-Fulcher temperature $T_{0}$ were determined for the structural glass Rb1-x[N(H1-yDy)4]x(H1-yDy)2PO4 ($x{=}0.5$, $y{=}0{\sim}1.0$) by the measurement of the complex dielectric constant. The values of $T_{\text{m}}$ and $T_{0}$ increase markedly with the deuteration rate $y$. It is found that the polydispersive nature of the dielectric dispersion becomes appreciable below $T_{\text{m}}$. The breadth of the relaxation time distribution increases as temperature approaches $T_{0}$.

著者

Liu Xizheng He Ping Li Huiqiao Ishida Masayoshi Zhou Haoshen

出版者

Elsevier B.V.

雑誌

Journal of alloys and compounds (ISSN:09258388)

巻号頁・発行日

vol.552, pp.76-82, 2012-03

被引用文献数

73 17

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The capacity fading and lower rate of layered cathode materials prohibited widely applications in lithium ion batteries. In this paper, V2O5 was coated on the surface of LiNi1/3Co1/3Mn1/3O2 to enhance its electrochemical performance at a voltage range of 2.8–4.5 V. The prepared materials were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscope (TEM). The capacity retention at the 100th cycle have been increased from 62% to over 80% for the 3 wt.% V2O5 coated sample. The rate performance has been improved by V2O5 coating which mainly because of the coating layer enhance the surface electronic/ionic transport. Cyclic voltammetry (CV) showed that the redox properties of the pristine sample have a more obvirous changes after charge–discharge cycles compared with the coated samples. Electrochemical impedance spectroscopy (EIS) results suggest that the V2O5 coating layer play an important role in suppressing the increase of cell impedance with cycling especially for the increase of charge-transfer resistance (Rct).