Effects of partial substitutions of cerium and aluminum on the hydrogenation properties of La_(0.65-x)Ce_xCa _1.03Mg_1.32Ni_(9-y)Al_y alloy

Hydrogen in metal hydrides could be one of the promising energy storage mediums to address the intermittent nature of renewable energy. To convert the hydrogen energy to electricity, the storage system has to be coupled with a fuel cells system. Hence, it is important to design a hydrogen storage system that meets the operating requirements for a fuel cell system. In this work, the effects of partial substitution of both cerium and aluminum on the hydrogenation properties of La_(0.65-x)Ce_xCa_1.03Mg _1.32Ni_(9-y)Al_y alloys were investigated simultaneously using factorial design. Both Ce and Al additions greatly improved the reversibility of hydrogen storage capacity. However, the maximum hydrogen storage capacity and absorption kinetics can be reduced by the additions. As Ce and Al gave opposite effects on the absorption and desorption plateaus, they could be used to tune the properties of the alloys to the desired operating conditions for fuel cell applications.