Nickel cadmium AA batteries (what was available in the 90s) were not great. They self-drained to flat after a month, and had "charge cycle memory," so if you di

Nickel cadmium AA batteries (what was available in the 90s) were not great. They self-drained to flat after a month, and had "charge cycle memory," so if you discharged them a couple times to, say, 60%, that became the cell capacity. Even fully charged, they only put out 1.2v. Nickel metal hydride, and specifically Eneloops, were a game changer, as their self-discharge was only 10%/month, and had virtually no charge cycle memory.