The effects of a combination hot-immersion and slow-charging method on the activation of a Zr-based alloy were investigated. A Zr0.7Ti0.3Cr0.3Mn0.3V0.4Ni1.0 alloy electrode was treated with two steps: alloy electrodes were immersed at 80 degrees C: for 12 h in a KOH solution and then charged at a low current density for one cycle. It was found that the alloy electrode activation was greatly improved after this hot-immersion and slow-charging treatment, and furthermore the treated electrodes were fully activated at the first normal cycle. The effects of this treatment are discussed on the basis of results obtained by scanning electron microscopy, Anger electron spectroscopy, and inductively coupled plasma spectroscopy. The hot-immersion and slow-charging method was successfully applied to the formation process of 80 Ah Ni/MH cells using this Zr-based alloy.