Metal hydride container

A critical issue is the stabiUty of the hydride electrode in the cell environment. A number of hydride formulations have been developed. Table 5 shows hydride materials that are now the focus of attention. Most of these are Misch metal hydrides containing additions of cobalt, aluminum, or manganese. The hydrides are prepared by making melts of the formulations and then grinding to fine powers. The electrodes are prepared by pasting and or pressing the powders into metal screens or felt. The additives are reported to retard the formation of passive oxide films on the hydrides. 

Metal hydrides containing transition metal (TM)-hydrogen complexes, with the transition metal in a formally low oxidation state, are of fundamental interest for clarifying how an electron-rich metal atom can be stabilized without access to the conventional mechanism for relieving the electron density by back-donation to suitable ligand orbitals. By reacting electropositive alkali or alkaline earth metals ( -elements) with group 7, 8, 9, and 10 transition metals in... 

K Yvon, B. BertheviUe, Magnesium based ternary metal hydrides containing alkali and alkaline-earth elements, J. Alloys Compd. 425 (2006) 101-108. 

Many metals react exothermally and reversibly with hydrogen according to Reaction 1. In many cases, the resulting metal hydrides contain more... 

Metal hydrides contain hydrogen with a —1 oxidation number. Since calcium always has a +2 oxidation number, there must be two H ions per Ca2+ ion. 

The alkali metal hydrides contain alkali metal cations and H- anions in a face-centered cubic crystal structure like that of sodium chloride (Section 10.9). Alkali metal hydrides are also ionic in the liquid state, as shown by the fact that the molten compounds conduct electricity. 

The hydrogen produced by the electrolyser is initially stored in an intermediate buffer of 1 m3 water volume, from which it can be transferred to one of the two storage systems metal hydride storage or pressurised gas (at 200 bar). The metal hydride storage system manufactured by GfE mbH consists of an intermediate buffer, a hydrogen purification unit, a metal hydride container and a cooling water supply system. 

This paper presents and compares current ideas about the nature of metallic hydrides contained in three somewhat overlapping but basically different models of metallic hydrides, which are referred to according to the postulated nature of the hydrogen as interstitial-atomic, protonic, and hydridic. 

M. Kritikos D. Nordus (1991). J. Solid State Chem., 93,256-262. Synthesis and characterization of ternary alkaline-earth transition-metal hydrides containing octahedral [Ru(II)H5] and [Os(II)H6] complexes. 

Tetrakis(organophosphorus)metal hydrides (containing one, two, three, or four hydride nuclei) have recently attracted considerable attention in connection with their stereochemical behavior1 and reaction chemistry.2 Detailed nuclear magnetic resonance studies and line-shape analyses have substantiated stereochemical nonrigidity in many of these complexes in solution and have yielded mechanistic information about the intramolecular-exchange processes.3... 

Note that metal hydrides, containing hydrogen ion, develop hydrogen at the anode when subjected to electrolysis. 

Metal deuteride Metal hydride containing hydrogen in an isotopic purity >99% D. 

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