165 research outputs found
Corrosion Behavior of Aluminum-Based Materials in Polymer Electrolyte Membrane Fuel Cell Environment
No full text岩手大学博士（理工学）原著論文
Corrosion Behavior of Pure Aluminum in the Simulated and Real Environments for Use as a Bipolar Plate Component in Polymer Electrolyte Membrane Fuel Cells
Aklima Jahan, Md. Ashraful Alam, Eiichi Suzuki, Hitoshi Yashiro
Industrial & Engineering Chemistry Research 62 (47), 20223-20235, 2023doctoral thesi
Development of high power lithium-ion batteries: Layer Li[Ni(0.4)Co(0.2)Mn(0.4)]O(2) and spinel Li[Li(0.1)Al(0.05)Mn(1.85)]O(4)
No full textLayer Li[Ni0.4Co0.2Mn0.4]O2 and lithium excess spinel Li[Li0.1Al0.05Mn1.85]O4 were compared as positive electrode materials for high power lithium-ion batteries. Physical properties were examined by Rietveld refinement of X-ray diffraction pattern and scanning electron microscopic studies. From continuous charge and discharge tests at higher currents and different temperature environments using 3Ah class lithium-ion batteries, it was found that both materials presented plausible battery performances such as rate capability, cyclability at 60 °C at elevated temperature, and low temperature properties as well
Formation of a Continuous Solid-Solution Particle and its Application to Rechargeable Lithium Batteries
No full textHigh-energy electrode materials are under worldwide development for rechargeable lithium batteries to be used in electric vehicles and other energy storage applications. High capacity and energy density are readily achievable using Ni-rich Li[Ni1-xMx]O2 (x = 0.10.2, M = Ni, Co, Mn, and Al) cathodes. Unfortunately, their structural instability is associated with severe capacity fading on cycling, which hinders practical applications. Here, a method is presented for producing a continuous compositional change between Li[Ni0.8Co0.2]O2 (center) and Li[Ni0.8Co0.01Mn0.19]O2 (surface) in a spherical particle, resulting in an average composition of Li[Ni0.8Co0.06Mn0.14]O2. The chemical composition in the particle is gradually altered by decreasing the Co concentration while adding Mn content. The Ni content remains fixed. Coin cells with the solid-solution cathode deliver a specific capacity over 210 mAh g1 in the voltage range of 2.74.3 V vs. Li/Li+ with capacity retention of 85% over 100 cycles at 25 and 55 degrees C. The main exothermic temperature upon heating appears at around 250 degrees C with relatively low heat generation (810 J g1). The presence of the tetravalent Mn at the particle surface is mainly responsible for the high capacity upon cycling and excellent thermal properties.H.-J.N. and S.-T.M. contributed equally to this work. This work was supported by the Human Resources Development of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government Ministry of Knowledge Economy (No. 20104010100560) and the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (No. 2009-0092780
Effect of AlF3 Coating on rhermal Behavior of Chemically Delithiated Li-0.35[Ni1/3Co1/3Mn1/3]O-2
No full textThe thermal behavior of chemically delithiated Li-0.35[Ni1/3Co1/3Mn1/3]O-2 and the AlF3-coated material was studied ill the temperature range from room temperature to 600 degrees C. Thermogravimetric analysis results showed that the uncoated and the AlF3-COated Li-0.35[Ni1/3Co1/3Mn1/3]O-2 powders experienced distinct Weight loss with increasing temperature, Of which the weight loss was ascribed to oxygen release from the active materials. The released oxygen amount was less for the AlF3-coated Li-0.35[Ni1/3Co1/3Mn1/3]O-2 than the uncoated material, probably due to the blocking of the oxygen evolution by the AlF3 coating. The weight loss was associated with the irreversible phase transformation from a rhombohedral layer (R3 (m) over bar) Structure to a cubic spinel (Fd3m) Structure, as confirmed by in situ high-temperature X-ray diffraction. The reduced oxygen release brought about by the AlF3 coating delayed the phase transformation to the Cubic spinel Structure. This entailed shifts of the main exothermic reactions to higher temperatures for the active material in the presence of ail electrolyte. The AlF3 Coating remained oil the Surface of the active material to 300 degrees C. Thereafter, the layer changed to Li-Al-O with increasing temperature, as observed by the time-of-night secondary ion mass spectroscopy. The improved thermal properties of the chemically delithiated AlF3-coated Li-0.35[Ni1/3Co1/3Mn1/3]O-2 were ascribed to the Suppression of oxygen release from the active material, and this, ill turn, retarded the formation of the Cubic spinel phase.The authors thank Mr. S. Takahashi and N. Takahashi, Iwate University, for his helpful assistance in the experimental work. This research Was supported by the WCU (World Class University) program through the Korea Science and Engineering Foundation funded by the Ministry of education, Science, and Technology (R31-2008-000-10092). Argonne is managed by UChicago Argonne, LLC, for the U.S. Department of Energy under Contract DE-AC02-06CH11357
Data for aerosol assimilations by NICAM.19/2DVar (Version 1.2)
No full text<p>These data are a set of assimilations using a global aerosol model, NICAM.19, coupled to a 2-dimensional variational method (2DVar). The data in version 1.2 were used in the following manuscript.</p>
<p>D. Goto, T. Nishizawa, J. Uchida, K. Yumimoto, Y. Jin, A. Higurashi, A. Shimizu, S. Sugata, H. Yashiro, M. Hayasaki, T. Dai, Y. Cheng, and H. Tanimoto, Development of an aerosol assimilation system using a global non-hydrostatic model, a 2-dimensional variation method, and multiple satellite-based aerosol products, submitted to Journal of Advances in Modeling Earth Systems.</p>
1A2-D01 Study on Moving Mechanism and Control of Three-Leg Electromagnet-Type of Micro Robot : Prototyping and Experimant of the Basic Characteristics on the Straight Running
No full textThermal decomposition of potassium nitrate in the potassium nitrate-lodine cycle for hydrogen production.
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