25 research outputs found

    High Specific Energy Lithium Cells for Space Exploration

    Full text link
    The paper discusses development under an ESA TRP activity (Contract No. 4000109879/13/NL/LvH) with a target of high specific energy Lithium-ion cells, capable of operating under low temperature conditions, i.e. −40 °C. Such cells may be encountered in future exploration missions, which do not consider the use of Radioisotope Heater Units. During the activity, ≥1 Ah silicon-based high energy density prototype cells, following components characterization and optimization, were designed, developed, manufactured and tested under room and subzero temperature conditions down to −40 °C. The developed and tested prototype cells exhibited energy density of around 208 Wh/Kg at room temperature under C/10 charge-discharge rate within voltage range of 2.8 V and 4.1 V. Moreover, the prototype cells could retain and deliver more than 75% of their capacity at room temperature upon cycling at −40 °C, demonstrating an energy density of 140 Wh/kg

    Institutional pedagogical waypoints : reflections on doctoral journeys between Taiwan and Australia

    Full text link
    Spatial, social and academic journeys undertaken between Taiwan and Australia for doctoral education are the focus of reflection here. The discussion centres on the authors’ experiences of, on the one hand, the development of a Faculty of Education’s doctoral pedagogies in the early 2000s to reflect its international PhD candidature profile – especially from Taiwan – and, on the other, of Taiwanese doctoral candidates’ journeys through their PhDs in the Faculty. The authors write from their particular perspectives: Evans as an Australian academic and a manager of doctoral studies, and Liou as a Taiwanese academic pursuing her doctorate in an Australian university. The article considers the Australian and Taiwanese doctoral contexts between which the students transited. The institutional pedagogical strategies, from pre-enrolment to completion, are examined as waypoints on the doctoral journey for both staff and candidates

    Pd-Ir alloy as an anode material for borohydride oxidation

    Get PDF
    A Pd-Ir alloy (1:1) coated on microfibrous carbon (11 μm diameter) supported on a titanium plate was evaluated as an electrode for the anodic oxidation of borohydride. The hydrogen generated, due to the parallel reaction of borohydride hydrolysis, was measured during the electrolysis obtaining less than 0.1 cm 3 min -1 H 2 between -1 and 0 V vs. Hg/HgO (-0.86 and 0.14 V vs. SHE), while the current densities for the oxidation of borohydride were up to 367 mA cm -2 in 0.5 mol dm -3 NaBH 4 + 3 mol dm -3 NaOH. The low rate of hydrogen generation suggests that Pd-Ir could be a promising catalyst for borohydride oxidation. However, higher rates of hydrogen were generated at the open circuit potential, which is inconvenient in the direct borohydride fuel cell. Cyclic voltammetry allowed analysis of the oxidation peaks due to the borohydride oxidation. To obtain a further understanding of the borohydride oxidation mechanism at Pd-Ir electrodes, density functional theory (DFT) was used to examine the reaction mechanism at Pd 2 -Ir 1 (111) and Pd 2 -Ir 2 (111) surfaces. The competition between borohydride oxidation and hydrogen evolution on the Pd-Ir alloys is compared with that on pure Pd(111), suggesting that the presence of Ir favors borohydride oxidation rather than hydrogen evolution. © 2014 Elsevier B.V. All rights reserved

    High Specific Energy Lithium Cells for Space Exploration

    No full text
    The paper discusses development under an ESA TRP activity (Contract No. 4000109879/13/NL/LvH) with a target of high specific energy Lithium-ion cells, capable of operating under low temperature conditions, i.e. −40 °C. Such cells may be encountered in future exploration missions, which do not consider the use of Radioisotope Heater Units. During the activity, ≥1 Ah silicon-based high energy density prototype cells, following components characterization and optimization, were designed, developed, manufactured and tested under room and subzero temperature conditions down to −40 °C. The developed and tested prototype cells exhibited energy density of around 208 Wh/Kg at room temperature under C/10 charge-discharge rate within voltage range of 2.8 V and 4.1 V. Moreover, the prototype cells could retain and deliver more than 75% of their capacity at room temperature upon cycling at −40 °C, demonstrating an energy density of 140 Wh/kg

    High Specific Energy Lithium Cells for Space Exploration

    No full text
    The paper discusses development under an ESA TRP activity (Contract No. 4000109879/13/NL/LvH) with a target of high specific energy Lithium-ion cells, capable of operating under low temperature conditions, i.e. −40 °C. Such cells may be encountered in future exploration missions, which do not consider the use of Radioisotope Heater Units. During the activity, ≥1 Ah silicon-based high energy density prototype cells, following components characterization and optimization, were designed, developed, manufactured and tested under room and subzero temperature conditions down to −40 °C. The developed and tested prototype cells exhibited energy density of around 208 Wh/Kg at room temperature under C/10 charge-discharge rate within voltage range of 2.8 V and 4.1 V. Moreover, the prototype cells could retain and deliver more than 75% of their capacity at room temperature upon cycling at −40 °C, demonstrating an energy density of 140 Wh/kg
    corecore