Hydrogen storage is a significant area of energy materials research and there have been extensive efforts into the discovery and development of lightweight materials. Although many new systems have been synthesised over the past five years, no material has yet been developed that has reversibility properties that match those of transition metal hydrides such as LaNi5Hx. We have recently determined the structures of the first two members of an entirely new class of complex hydrides. The decomposition of many complex hydrides occurs from the molten state, reinforcing the conclusion that disorder and ion mobility are important in dehydrogenation mechanisms. We wish to use the EMU muon spectrometer to investigate disorder and ion mobility in these two amide¿borohydrides as a function of temperature, in order to understand how their reversibility, and that of related systems may be improved.