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Anodizing of magnesium was studied in solutions containing 3MKOH+0.6MKF+0.21MNa3PO4 , with and without addition of 0.4 M and 1.1 M of aluminate. At constant applied current, the process occurs in two stages. First, the voltage rises linearly until an initial breakdown occurs. A thin and compact oxide film is formed at this stage. In the second stage an intense continuous spark is maintained on the metal surface. A thick oxide film is formed at the site of sparking. The formation of the film is accompanied by voltage oscillation and gas evolution. The anodic films formed under continuous breakdown conditions are rough and porous and enriched in aluminum. Anodic films formed in a bath containing 1.1 M aluminate at 15 normalmA/cm2 are composed of a single oxide phase MgAl2O4 spinel. © 1999 The Electrochemical Society. All rights reserved.

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The potential and research surrounding metal hydride (MH) based thermal energy storage is discussed, focusing on next generation thermo-chemical energy storage (TCES) for concentrated solar power. The site availability model to represent the reaction mechanisms of both the forward and backward MH reaction is presented, where this model is extrapolated to a small pilot scale reactor, detailing how a TCES could function/operate in a real-world setting using a conventional shell & tube reactor approach. Further, the important parameter of effective thermal conductivity is explored using an innovative multi-scale model, to providing extensive and relevant experimental data useful for reactor and system design. Promising high temperature MH material configurations may be tuned by either destabilisation, such as using additions to Ca and Sr based hydrides, or by stabilisation, such as fluorine addition to NaH, MgH2, or NaMgH3. This versatile thermodynamic tuning is discussed, including the challenges in accurately measuring the material characteristics at elevated temperatures (500 –700 °C). Attention to scale up is explored, including generic design and prototype considerations, and an example of a novel pilot-scale pillow-plate reactor currently in development; where materials used are discussed, overall tank design scope and system integration.