In this work, the electrochemical discharge capacity of melt-spun (MmY)(1) (NiCoMnAI)(5) ribbons, in which the content of yttrium was 0-2.5wt%, was studied in the temperature range of 30 similar to 80 degrees C. It was found that adding element yttrium made the electrochemical capacity of the compounds increased. The capacity obtained was 333mAh/g at 30 degrees C and 247 mAh/g at 80 degrees C when the content of yttrium was 2.Owt%. In addition, 70 similar to 85% recovery of the capacity was obtained due to better antioxidation. The increase of charging/discharging efficiency with yttriurn substitution for Mm. in melt-spun ribbons illustrated by the potential characteristics of charging/discharging is ascribed to the flatter and lower hydride formation potential, as well as the higher hydrogen evolution potential. Moreover, This effect is more prominent with increasing yttriurn content.