著者

Liu Xizheng Li Huiqiao Li De Ishida Masayoshi Zhou Haoshen

出版者

Elsevier B.V.

雑誌

Journal of power sources (ISSN:03787753)

巻号頁・発行日

vol.243, pp.374-380, 2013-12

被引用文献数

84

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Layered LiNi1/3Co1/3Mn1/3O2 was modified by poly(3,4-dioxyethylenethiophene) PEDOT via a facile method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and infrared spectroscopy (IR). PEDOT modified samples exhibited both improved rate and cycle performance compared with the pristine LiNi1/3Co1/3Mn1/3O2. At a charge/discharge current of 1500 mA g−1, the discharge capacity was improved from 44.3 to 73.9 mAh g−1. The sample with 2 wt% and heat treated at 300 °C showed the optimized electrochemical performance. Galvanostatic intermittent titration technique (GITT) and cyclic voltammetry (CV) results indicated that the battery polarization of coated samples have been suppressed obviously because the PEDOT layer facilitated the electron transfer at the interface of electrode and electrolyte.

著者

Ito Hiroshi Maeda Tetsuhiko Nakano Akihiro Hwang Chul Min Ishida Masayoshi Kato Atsushi Yoshida Tetsuya

出版者

Elsevier Ltd.

雑誌

International journal of hydrogen energy (ISSN:03603199)

巻号頁・発行日

vol.37, no.9, pp.7418-7428, 2012-05

被引用文献数

132 11

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Experimentalstudy on proton exchange membrane (PEM) electrolyzer was carried out focusing on the effect of pore structural properties of currentcollectors, such as porosity and pore diameter. Various titanium (Ti)-felt substrates with different porosities and pore diameters (measured by capillary flow porometry) were used as the anode currentcollector. Results show that when the mean pore diameter of the currentcollector was larger than 10 μm, the electrolysis performance improved with decreasing pore diameter. In contrast, changes in porosity had no significant effect on the cell performance when the porosity exceeded 0.50. The flow pattern of two-phase flow in the flow channel was discussed in terms of its relationship to bubble size and to pore diameter of the currentcollector. Finally, correlation between the calculated membrane resistance and the measured pore diameter of the currentcollectors suggest that larger bubbles generated from larger pores tend to become long bubbles in the channel, thus hindering the water supply to the membrane.

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).