A common way to revive an old NiMh pac is to cycle it like you describe. Charge it at 0.5 - 1.0amps (lower is prob better) and then run it to discharge it unless your charger has a discharger - then discharge at at 0.5amps. Then repeat. What you're looking for is improvement in run time or the mah going into the batt when charged.

Even better if your charger has a cycling feature - set it to 3 cycles and charge at 0.5, discharge at 0.5. At the end look at the discharged mah, if the number is still climbing, try 3 more cycles. If the discharge mah is not getting any better, the battery is not going to improve and needs to be replaced.


Sometimes this will bring a pack back, sometimes it doesn't.