In one of my DIY battery mods, that I used four 1.2v NiMH batteries, I added a LM2940-5 regulator to ensure the cut-off of the batteries in case their voltage drops under 2.5v (in total). Also this regulator has the ability to limit the current to MAX 1A !!!! Another measure to encure steady discharge rate from the batteries!!!
Thanos
Thanos