Kei Ogasawara
Southern California Gas Company
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Publication
Featured researches published by Kei Ogasawara.
Journal of The Electrochemical Society | 2007
Kei Ogasawara; Harukuni Kameda; Yoshio Matsuzaki; Teruhiro Sakurai; Toshihiro Uehara; Akihiro Toji; Natsuko Sakai; Katsuhiko Yamaji; Teruhisa Horita; Harumi Yokokawa
A ferritic alloy interconnect was studied through solid oxide fuel cell (SOFC) stack operation at intermediate temperatures. Certain pretreatment of the alloy surface proved to be effective for controlling initial degradation of the stack performance, presumably by the formation of stable and conductive oxide scale. Evidences were found that glass sealant containing alkali metals affected the oxidation behavior of the alloy surface not in contact with the cathode material. A thick scale rich in iron tended to be formed at the air side in the vicinity of the glass sealant, while a thinner scale rich in chromium was preferably found in the other. Alkali metal components were found in that thick oxide layer. At the interface between the alloy and the cathode current collector, a strontium chromate, which might cause chromium poisoning at the cathode/electrolyte interface, was formed, and that was found to be distributed over the current collector away from the interface. A thermodynamic equilibrium calculation using a thermodynamic database revealed that the chromium component is highly reactive with alkali or alkali earth metals and forms stable chromates. Some of those chromates are very stable and may hinder the formation of stable oxide scale such as Mn-Cr-O spinels or Cr 2 O 3 , and may cause the severe oxidation of the alloy.
international conference on fuel cell science engineering and technology fuelcell collocated with asme international conference on energy sustainability | 2006
Kenjiro Fujita; Yoshio Matsuzaki; Shoji Yamashita; Kei Ogasawara; Teruhiro Sakurai
The voltage loss in a single cell of a segmented-in-series flat-tube-type solid oxide fuel cell (SOFC) stack was evaluated. The stack exhibits a particular configuration, and the current flows along an in-plane direction in the anode and cathode; this differs from conventional planar-type SOFCs. Distributions of the current in the cell were studied in detail for many parameters such as the length of electrodes and conductivities of the cell components. Gas diffusion in a porous substrate and anode and the fuel utilization affect the concentration polarization; thus, they were also considered. By using the simulation results, appropriate configurations for the cell and stack were designed, and the simulation was validated by performance tests for a practical fuel cell stack. The stack exhibited a high performance of 0.76 V at 0.2 A/cm2 at Uf = 81.6% with dry H2 fuel, yielding a DC energy conversion efficiency of 53.6% HHV. Moreover, a bundle comprising 34 stacks was also fabricated, and excellent values of output voltage (342.5 V), output power (338.3 W), and electrical efficiency (49.5% HHV) at a current density of 0.2 A/cm2 were obtained.Copyright
International Journal of Hydrogen Energy | 2008
Teruhisa Horita; Katsuhiko Yamaji; Harumi Yokokawa; Akihiro Toji; Toshihiro Uehara; Kei Ogasawara; Harukuni Kameda; Yoshio Matsuzaki; Satoshi Yamashita
Solid State Ionics | 2008
Teruhisa Horita; Haruo Kishimoto; Katsuhiko Yamaji; Yueping Xiong; Manuel E. Brito; Harumi Yokokawa; Yoshitaka Baba; Kei Ogasawara; Harukuni Kameda; Yoshio Matsuzaki; Satoshi Yamashita; Nobutaka Yasuda; Toshihiro Uehara
Archive | 2007
Yoshitaka Baba; Harukuni Kameda; Hideto Kurokawa; Yoshio Matsuzaki; Kei Ogasawara; Satoshi Yamashita; 治邦 亀田; 慶 小笠原; 敏 山下; 良雄 松崎; 好孝 馬場; 英人 黒川
Journal of the American Ceramic Society | 2005
Isamu Yasuda; Kei Ogasawara; Masakazu Hishinuma
Archive | 1999
Yoshio Matsuzaki; Kei Ogasawara; 慶 小笠原; 良雄 松崎
Archive | 2004
Kenjiro Fujita; Yoshio Matsuzaki; Kei Ogasawara; Teruhiro Sakurai; 慶 小笠原; 良雄 松崎; 輝浩 桜井; 顕二郎 藤田
Archive | 2006
Yoshio Matsuzaki; Kei Ogasawara; Shoji Yamashita; 慶 小笠原; 祥二 山下; 良雄 松崎
Archive | 2006
Yoshio Matsuzaki; Kei Ogasawara; Teruhiro Sakurai; Takaaki Somekawa; 慶 小笠原; 良雄 松崎; 貴亮 染川; 輝浩 桜井
Collaboration
Dive into the Kei Ogasawara's collaboration.
National Institute of Advanced Industrial Science and Technology
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