With COP and dynamic characteristics in refrigeration cycle as criteria,a new metal hydride couple--LaNi4.61Mn0. 26Al0. 13/La0. 6Y0. 4Ni4.8Mn0.2 was selected by establishing calculation procedure and metal hydride selection model. The experimental results show that the refigeration cycle of the selected couple is good in the performance. The recovered waste heat and refrigeration power from exhaust gas of several kinds of automobile are calculated by waste-heat formula,coefficient RQ and COP. Refrigeration cycle of the new couple can satisfy the air-conditioning requirement of truck and car and is not enough in passenger car ,according to the respective cooling load.