Hydrogen storage, Chapter hydrides,

Union Carbide showed the possibility of developing D-size hydrogen-nickel batteries with satisfactory performance. However, safety and cost considerations have restricted the applications of such units and the discovery of hydrogen storage alloys led to the development of the nickel-metal hydride secondary cell which was described in Chapter 6. 

Even though the first metal hydride was discovered more than 100 years ago, intensive research on this class of materials is relatively new. Investigation of the hydrogen-metal interactions is very interesting from a fundamental point of view as well as for practical applications. In this chapter, we focus on the materials and properties that are especially important for hydrogen storage applications. 

In this chapter, the fundamental characteristics of metal hydrides as hydrogen storage materials have been reviewed. Their potential for practical applications is well known but more research need to be done in order to find a system that will meet the industry s criteria. This research could be broadly divided in the following way ... 

Chapter 9 Reversible Hydrides for On-Board Hydrogen Storage.191... 

This chapter will first explain the theory of destabilisation and then move on to look at specific examples starting with the destabilisation of complex hydrides with separate sections devoted to different classes of destabilisation agents first metal hydrides, then non-hydride systems (where either an element or alloy which does not hydride or an inorganic salt is added as the destabilisation agent) and finally attempts to use another complex hydride to form a destabilised multicomponent system. The penultimate section summarises the work reported on other multicomponent hydrogen storage systems, predominantly the destabilisation of binary hydrides by other elements, and the chapter is concluded with an outlook of potential future research. 

The final part of the book illustrates the relevance of metal-hydrogen bonds in biochemistry and materials science. A chapter by Henderson reviews the implication of hydrides in some enzymatic processes relevant to biochemistry. Ross shows the combined use of experiment and theory for the investigation of hydrogen in metals, while a closing chapter by Maeland shows the state of the art in the development of hydrogen storage materials for the application in automotive technology. 

Hydrogen storage techniques can be roughly classified into liquid, pressurized, and metal hydride [8]. The development of storage technologies is a broad research field that will not be considered in this chapter. 

Besides AB, some of its derivatives have also been investigated for hydrogen storage, especially to overcome the previously mentioned problems. The derivatives hydrazine borane (HB) [13], guanidinium borohydride (GBH) [12], ethylenediamine bisborane (EDB) [43], methylguanidinium borohydride (Me-GBH) [44], and different alkyl amine boranes are the most interesting (Fig. 40.3) [45, 14]. Another compound class between molecular and metal hydride storage materials is that of metal amido boranes, which is not discussed in this chapter [46]. 

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