International Journal of Hydrogen Energy, Vol.35, No.13, 6578-6582, 2010
Rehydrogenation and cycle studies of LiBH(4)-CaH(2) composite
Rehydrogenation behavior of 6LiBH(4) + CaH(2) composite with NbF(5) has been studied between 350 and 500 degrees C after dehydrogenation at 450 degrees C. The composite exhibits the best rehydrogenation feature at 450 degrees C in terms of the overall rehydrogenation rate and the amount of absorbed hydrogen. It is found that about 9 wt% hydrogen is absorbed at 450 degrees C for 12 h. Up to 10 dehydrogenation-hydrogenation cycles have been carried out for the composite. It is demonstrated that 6LiBH(4) + CaH(2) with 15 wt% NbF(5) maintains a reversible hydrogen storage capacity of about 6 wt% at 450 degrees C after a slight degradation between the 1st and 5th cycles. The addition of NbF(5) seems to improve the cycle properties by retarding microstructural coarsening during cycles. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.